OpenCloudOS-Kernel/drivers/soundwire/intel.c

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// SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause)
// Copyright(c) 2015-17 Intel Corporation.
/*
* Soundwire Intel Master Driver
*/
#include <linux/acpi.h>
#include <linux/debugfs.h>
#include <linux/delay.h>
#include <linux/module.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/auxiliary_bus.h>
#include <sound/pcm_params.h>
#include <linux/pm_runtime.h>
#include <sound/soc.h>
#include <linux/soundwire/sdw_registers.h>
#include <linux/soundwire/sdw.h>
#include <linux/soundwire/sdw_intel.h>
#include "cadence_master.h"
#include "bus.h"
#include "intel.h"
#define INTEL_MASTER_SUSPEND_DELAY_MS 3000
soundwire: cadence: add paranoid check on self-clearing bits The Cadence IP exposes a small number of self-clearing bits in the MCP_CONTROL and MCP_CONFIG_UPDATE registers. We currently do not check that those bits are indeed cleared, e.g. during resume operations. That could lead to resuming peripheral devices too early. In addition, if we happen to read these registers, update one of the fields and write the register back, we may be writing stale data that might have been cleared in hardware. These sort of race conditions could lead to e.g. doing a hw_reset twice or stopping a clock that just restarted. There is no clear way of avoiding these potential race conditions other than making sure that these registers fields are cleared before any read-modify-write sequence. If we detect this sort of errors, we only log them since there is no clear recovery possible. The only way out is likely to restart the IP with a suspend/resume cycle. Note that the checks are performed before updating the registers, as well as after the Intel 'sync go' sequence in multi-link mode. That should cover both the start and end of suspend/resume hardware configurations. The Multi-Master mode gates the configuration updates until the 'sync go' signal is asserted, so we only check on init and after the end of the 'sync go' sequence. The duration of the usleep_range() was defined by the GSYNC frequency used in multi-master mode. With a 4kHz frequency, any configuration change might be deferred by up to 250us. Extending the range to 1000-1500us should guarantee that the configuration change is completed without any significant impact on the overall resume time. Suggested-by: Bard Liao <yung-chuan.liao@linux.intel.com> Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com> Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com> Link: https://lore.kernel.org/r/20210714051349.13064-1-yung-chuan.liao@linux.intel.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
2021-07-14 13:13:49 +08:00
#define INTEL_MASTER_RESET_ITERATIONS 10
/*
* debug/config flags for the Intel SoundWire Master.
*
* Since we may have multiple masters active, we can have up to 8
* flags reused in each byte, with master0 using the ls-byte, etc.
*/
#define SDW_INTEL_MASTER_DISABLE_PM_RUNTIME BIT(0)
#define SDW_INTEL_MASTER_DISABLE_CLOCK_STOP BIT(1)
#define SDW_INTEL_MASTER_DISABLE_PM_RUNTIME_IDLE BIT(2)
#define SDW_INTEL_MASTER_DISABLE_MULTI_LINK BIT(3)
static int md_flags;
module_param_named(sdw_md_flags, md_flags, int, 0444);
MODULE_PARM_DESC(sdw_md_flags, "SoundWire Intel Master device flags (0x0 all off)");
enum intel_pdi_type {
INTEL_PDI_IN = 0,
INTEL_PDI_OUT = 1,
INTEL_PDI_BD = 2,
};
#define cdns_to_intel(_cdns) container_of(_cdns, struct sdw_intel, cdns)
/*
* Read, write helpers for HW registers
*/
static inline int intel_readl(void __iomem *base, int offset)
{
return readl(base + offset);
}
static inline void intel_writel(void __iomem *base, int offset, int value)
{
writel(value, base + offset);
}
static inline u16 intel_readw(void __iomem *base, int offset)
{
return readw(base + offset);
}
static inline void intel_writew(void __iomem *base, int offset, u16 value)
{
writew(value, base + offset);
}
static int intel_wait_bit(void __iomem *base, int offset, u32 mask, u32 target)
{
int timeout = 10;
u32 reg_read;
do {
reg_read = readl(base + offset);
if ((reg_read & mask) == target)
return 0;
timeout--;
usleep_range(50, 100);
} while (timeout != 0);
return -EAGAIN;
}
static int intel_clear_bit(void __iomem *base, int offset, u32 value, u32 mask)
{
writel(value, base + offset);
return intel_wait_bit(base, offset, mask, 0);
}
static int intel_set_bit(void __iomem *base, int offset, u32 value, u32 mask)
{
writel(value, base + offset);
return intel_wait_bit(base, offset, mask, mask);
}
/*
* debugfs
*/
#ifdef CONFIG_DEBUG_FS
#define RD_BUF (2 * PAGE_SIZE)
static ssize_t intel_sprintf(void __iomem *mem, bool l,
char *buf, size_t pos, unsigned int reg)
{
int value;
if (l)
value = intel_readl(mem, reg);
else
value = intel_readw(mem, reg);
return scnprintf(buf + pos, RD_BUF - pos, "%4x\t%4x\n", reg, value);
}
static int intel_reg_show(struct seq_file *s_file, void *data)
{
struct sdw_intel *sdw = s_file->private;
void __iomem *s = sdw->link_res->shim;
void __iomem *a = sdw->link_res->alh;
char *buf;
ssize_t ret;
int i, j;
unsigned int links, reg;
buf = kzalloc(RD_BUF, GFP_KERNEL);
if (!buf)
return -ENOMEM;
links = intel_readl(s, SDW_SHIM_LCAP) & GENMASK(2, 0);
ret = scnprintf(buf, RD_BUF, "Register Value\n");
ret += scnprintf(buf + ret, RD_BUF - ret, "\nShim\n");
for (i = 0; i < links; i++) {
reg = SDW_SHIM_LCAP + i * 4;
ret += intel_sprintf(s, true, buf, ret, reg);
}
for (i = 0; i < links; i++) {
ret += scnprintf(buf + ret, RD_BUF - ret, "\nLink%d\n", i);
ret += intel_sprintf(s, false, buf, ret, SDW_SHIM_CTLSCAP(i));
ret += intel_sprintf(s, false, buf, ret, SDW_SHIM_CTLS0CM(i));
ret += intel_sprintf(s, false, buf, ret, SDW_SHIM_CTLS1CM(i));
ret += intel_sprintf(s, false, buf, ret, SDW_SHIM_CTLS2CM(i));
ret += intel_sprintf(s, false, buf, ret, SDW_SHIM_CTLS3CM(i));
ret += intel_sprintf(s, false, buf, ret, SDW_SHIM_PCMSCAP(i));
ret += scnprintf(buf + ret, RD_BUF - ret, "\n PCMSyCH registers\n");
/*
* the value 10 is the number of PDIs. We will need a
* cleanup to remove hard-coded Intel configurations
* from cadence_master.c
*/
for (j = 0; j < 10; j++) {
ret += intel_sprintf(s, false, buf, ret,
SDW_SHIM_PCMSYCHM(i, j));
ret += intel_sprintf(s, false, buf, ret,
SDW_SHIM_PCMSYCHC(i, j));
}
ret += scnprintf(buf + ret, RD_BUF - ret, "\n PDMSCAP, IOCTL, CTMCTL\n");
ret += intel_sprintf(s, false, buf, ret, SDW_SHIM_PDMSCAP(i));
ret += intel_sprintf(s, false, buf, ret, SDW_SHIM_IOCTL(i));
ret += intel_sprintf(s, false, buf, ret, SDW_SHIM_CTMCTL(i));
}
ret += scnprintf(buf + ret, RD_BUF - ret, "\nWake registers\n");
ret += intel_sprintf(s, false, buf, ret, SDW_SHIM_WAKEEN);
ret += intel_sprintf(s, false, buf, ret, SDW_SHIM_WAKESTS);
ret += scnprintf(buf + ret, RD_BUF - ret, "\nALH STRMzCFG\n");
for (i = 0; i < SDW_ALH_NUM_STREAMS; i++)
ret += intel_sprintf(a, true, buf, ret, SDW_ALH_STRMZCFG(i));
seq_printf(s_file, "%s", buf);
kfree(buf);
return 0;
}
DEFINE_SHOW_ATTRIBUTE(intel_reg);
static int intel_set_m_datamode(void *data, u64 value)
{
struct sdw_intel *sdw = data;
struct sdw_bus *bus = &sdw->cdns.bus;
if (value > SDW_PORT_DATA_MODE_STATIC_1)
return -EINVAL;
/* Userspace changed the hardware state behind the kernel's back */
add_taint(TAINT_USER, LOCKDEP_STILL_OK);
bus->params.m_data_mode = value;
return 0;
}
DEFINE_DEBUGFS_ATTRIBUTE(intel_set_m_datamode_fops, NULL,
intel_set_m_datamode, "%llu\n");
static int intel_set_s_datamode(void *data, u64 value)
{
struct sdw_intel *sdw = data;
struct sdw_bus *bus = &sdw->cdns.bus;
if (value > SDW_PORT_DATA_MODE_STATIC_1)
return -EINVAL;
/* Userspace changed the hardware state behind the kernel's back */
add_taint(TAINT_USER, LOCKDEP_STILL_OK);
bus->params.s_data_mode = value;
return 0;
}
DEFINE_DEBUGFS_ATTRIBUTE(intel_set_s_datamode_fops, NULL,
intel_set_s_datamode, "%llu\n");
static void intel_debugfs_init(struct sdw_intel *sdw)
{
struct dentry *root = sdw->cdns.bus.debugfs;
if (!root)
return;
sdw->debugfs = debugfs_create_dir("intel-sdw", root);
debugfs_create_file("intel-registers", 0400, sdw->debugfs, sdw,
&intel_reg_fops);
debugfs_create_file("intel-m-datamode", 0200, sdw->debugfs, sdw,
&intel_set_m_datamode_fops);
debugfs_create_file("intel-s-datamode", 0200, sdw->debugfs, sdw,
&intel_set_s_datamode_fops);
sdw_cdns_debugfs_init(&sdw->cdns, sdw->debugfs);
}
static void intel_debugfs_exit(struct sdw_intel *sdw)
{
debugfs_remove_recursive(sdw->debugfs);
}
#else
static void intel_debugfs_init(struct sdw_intel *sdw) {}
static void intel_debugfs_exit(struct sdw_intel *sdw) {}
#endif /* CONFIG_DEBUG_FS */
/*
* shim ops
*/
static int intel_link_power_up(struct sdw_intel *sdw)
{
unsigned int link_id = sdw->instance;
void __iomem *shim = sdw->link_res->shim;
u32 *shim_mask = sdw->link_res->shim_mask;
struct sdw_bus *bus = &sdw->cdns.bus;
struct sdw_master_prop *prop = &bus->prop;
u32 spa_mask, cpa_mask;
u32 link_control;
int ret = 0;
u32 syncprd;
u32 sync_reg;
mutex_lock(sdw->link_res->shim_lock);
/*
* The hardware relies on an internal counter, typically 4kHz,
* to generate the SoundWire SSP - which defines a 'safe'
* synchronization point between commands and audio transport
* and allows for multi link synchronization. The SYNCPRD value
* is only dependent on the oscillator clock provided to
* the IP, so adjust based on _DSD properties reported in DSDT
* tables. The values reported are based on either 24MHz
* (CNL/CML) or 38.4 MHz (ICL/TGL+).
*/
if (prop->mclk_freq % 6000000)
syncprd = SDW_SHIM_SYNC_SYNCPRD_VAL_38_4;
else
syncprd = SDW_SHIM_SYNC_SYNCPRD_VAL_24;
if (!*shim_mask) {
dev_dbg(sdw->cdns.dev, "%s: powering up all links\n", __func__);
/* we first need to program the SyncPRD/CPU registers */
dev_dbg(sdw->cdns.dev,
"%s: first link up, programming SYNCPRD\n", __func__);
/* set SyncPRD period */
sync_reg = intel_readl(shim, SDW_SHIM_SYNC);
u32p_replace_bits(&sync_reg, syncprd, SDW_SHIM_SYNC_SYNCPRD);
/* Set SyncCPU bit */
sync_reg |= SDW_SHIM_SYNC_SYNCCPU;
intel_writel(shim, SDW_SHIM_SYNC, sync_reg);
/* Link power up sequence */
link_control = intel_readl(shim, SDW_SHIM_LCTL);
/* only power-up enabled links */
spa_mask = FIELD_PREP(SDW_SHIM_LCTL_SPA_MASK, sdw->link_res->link_mask);
cpa_mask = FIELD_PREP(SDW_SHIM_LCTL_CPA_MASK, sdw->link_res->link_mask);
link_control |= spa_mask;
ret = intel_set_bit(shim, SDW_SHIM_LCTL, link_control, cpa_mask);
if (ret < 0) {
dev_err(sdw->cdns.dev, "Failed to power up link: %d\n", ret);
goto out;
}
/* SyncCPU will change once link is active */
ret = intel_wait_bit(shim, SDW_SHIM_SYNC,
SDW_SHIM_SYNC_SYNCCPU, 0);
if (ret < 0) {
dev_err(sdw->cdns.dev,
"Failed to set SHIM_SYNC: %d\n", ret);
goto out;
}
}
*shim_mask |= BIT(link_id);
sdw->cdns.link_up = true;
out:
mutex_unlock(sdw->link_res->shim_lock);
return ret;
}
/* this needs to be called with shim_lock */
static void intel_shim_glue_to_master_ip(struct sdw_intel *sdw)
{
void __iomem *shim = sdw->link_res->shim;
unsigned int link_id = sdw->instance;
u16 ioctl;
/* Switch to MIP from Glue logic */
ioctl = intel_readw(shim, SDW_SHIM_IOCTL(link_id));
ioctl &= ~(SDW_SHIM_IOCTL_DOE);
intel_writew(shim, SDW_SHIM_IOCTL(link_id), ioctl);
usleep_range(10, 15);
ioctl &= ~(SDW_SHIM_IOCTL_DO);
intel_writew(shim, SDW_SHIM_IOCTL(link_id), ioctl);
usleep_range(10, 15);
ioctl |= (SDW_SHIM_IOCTL_MIF);
intel_writew(shim, SDW_SHIM_IOCTL(link_id), ioctl);
usleep_range(10, 15);
ioctl &= ~(SDW_SHIM_IOCTL_BKE);
ioctl &= ~(SDW_SHIM_IOCTL_COE);
intel_writew(shim, SDW_SHIM_IOCTL(link_id), ioctl);
usleep_range(10, 15);
/* at this point Master IP has full control of the I/Os */
}
/* this needs to be called with shim_lock */
static void intel_shim_master_ip_to_glue(struct sdw_intel *sdw)
{
unsigned int link_id = sdw->instance;
void __iomem *shim = sdw->link_res->shim;
u16 ioctl;
/* Glue logic */
ioctl = intel_readw(shim, SDW_SHIM_IOCTL(link_id));
ioctl |= SDW_SHIM_IOCTL_BKE;
ioctl |= SDW_SHIM_IOCTL_COE;
intel_writew(shim, SDW_SHIM_IOCTL(link_id), ioctl);
usleep_range(10, 15);
ioctl &= ~(SDW_SHIM_IOCTL_MIF);
intel_writew(shim, SDW_SHIM_IOCTL(link_id), ioctl);
usleep_range(10, 15);
/* at this point Integration Glue has full control of the I/Os */
}
static int intel_shim_init(struct sdw_intel *sdw, bool clock_stop)
{
void __iomem *shim = sdw->link_res->shim;
unsigned int link_id = sdw->instance;
int ret = 0;
u16 ioctl = 0, act = 0;
mutex_lock(sdw->link_res->shim_lock);
/* Initialize Shim */
ioctl |= SDW_SHIM_IOCTL_BKE;
intel_writew(shim, SDW_SHIM_IOCTL(link_id), ioctl);
usleep_range(10, 15);
ioctl |= SDW_SHIM_IOCTL_WPDD;
intel_writew(shim, SDW_SHIM_IOCTL(link_id), ioctl);
usleep_range(10, 15);
ioctl |= SDW_SHIM_IOCTL_DO;
intel_writew(shim, SDW_SHIM_IOCTL(link_id), ioctl);
usleep_range(10, 15);
ioctl |= SDW_SHIM_IOCTL_DOE;
intel_writew(shim, SDW_SHIM_IOCTL(link_id), ioctl);
usleep_range(10, 15);
intel_shim_glue_to_master_ip(sdw);
u16p_replace_bits(&act, 0x1, SDW_SHIM_CTMCTL_DOAIS);
act |= SDW_SHIM_CTMCTL_DACTQE;
act |= SDW_SHIM_CTMCTL_DODS;
intel_writew(shim, SDW_SHIM_CTMCTL(link_id), act);
usleep_range(10, 15);
mutex_unlock(sdw->link_res->shim_lock);
return ret;
}
static void intel_shim_wake(struct sdw_intel *sdw, bool wake_enable)
{
void __iomem *shim = sdw->link_res->shim;
unsigned int link_id = sdw->instance;
u16 wake_en, wake_sts;
mutex_lock(sdw->link_res->shim_lock);
wake_en = intel_readw(shim, SDW_SHIM_WAKEEN);
if (wake_enable) {
/* Enable the wakeup */
wake_en |= (SDW_SHIM_WAKEEN_ENABLE << link_id);
intel_writew(shim, SDW_SHIM_WAKEEN, wake_en);
} else {
/* Disable the wake up interrupt */
wake_en &= ~(SDW_SHIM_WAKEEN_ENABLE << link_id);
intel_writew(shim, SDW_SHIM_WAKEEN, wake_en);
/* Clear wake status */
wake_sts = intel_readw(shim, SDW_SHIM_WAKESTS);
wake_sts |= (SDW_SHIM_WAKEEN_ENABLE << link_id);
intel_writew(shim, SDW_SHIM_WAKESTS_STATUS, wake_sts);
}
mutex_unlock(sdw->link_res->shim_lock);
}
static int intel_link_power_down(struct sdw_intel *sdw)
{
u32 link_control, spa_mask, cpa_mask;
unsigned int link_id = sdw->instance;
void __iomem *shim = sdw->link_res->shim;
u32 *shim_mask = sdw->link_res->shim_mask;
int ret = 0;
mutex_lock(sdw->link_res->shim_lock);
if (!(*shim_mask & BIT(link_id)))
dev_err(sdw->cdns.dev,
"%s: Unbalanced power-up/down calls\n", __func__);
sdw->cdns.link_up = false;
intel_shim_master_ip_to_glue(sdw);
*shim_mask &= ~BIT(link_id);
if (!*shim_mask) {
dev_dbg(sdw->cdns.dev, "%s: powering down all links\n", __func__);
/* Link power down sequence */
link_control = intel_readl(shim, SDW_SHIM_LCTL);
/* only power-down enabled links */
spa_mask = FIELD_PREP(SDW_SHIM_LCTL_SPA_MASK, ~sdw->link_res->link_mask);
cpa_mask = FIELD_PREP(SDW_SHIM_LCTL_CPA_MASK, sdw->link_res->link_mask);
link_control &= spa_mask;
ret = intel_clear_bit(shim, SDW_SHIM_LCTL, link_control, cpa_mask);
if (ret < 0) {
dev_err(sdw->cdns.dev, "%s: could not power down link\n", __func__);
/*
* we leave the sdw->cdns.link_up flag as false since we've disabled
* the link at this point and cannot handle interrupts any longer.
*/
}
}
mutex_unlock(sdw->link_res->shim_lock);
return ret;
}
static void intel_shim_sync_arm(struct sdw_intel *sdw)
{
void __iomem *shim = sdw->link_res->shim;
u32 sync_reg;
mutex_lock(sdw->link_res->shim_lock);
/* update SYNC register */
sync_reg = intel_readl(shim, SDW_SHIM_SYNC);
sync_reg |= (SDW_SHIM_SYNC_CMDSYNC << sdw->instance);
intel_writel(shim, SDW_SHIM_SYNC, sync_reg);
mutex_unlock(sdw->link_res->shim_lock);
}
static int intel_shim_sync_go_unlocked(struct sdw_intel *sdw)
{
void __iomem *shim = sdw->link_res->shim;
u32 sync_reg;
int ret;
/* Read SYNC register */
sync_reg = intel_readl(shim, SDW_SHIM_SYNC);
/*
* Set SyncGO bit to synchronously trigger a bank switch for
* all the masters. A write to SYNCGO bit clears CMDSYNC bit for all
* the Masters.
*/
sync_reg |= SDW_SHIM_SYNC_SYNCGO;
ret = intel_clear_bit(shim, SDW_SHIM_SYNC, sync_reg,
SDW_SHIM_SYNC_SYNCGO);
if (ret < 0)
dev_err(sdw->cdns.dev, "SyncGO clear failed: %d\n", ret);
return ret;
}
static int intel_shim_sync_go(struct sdw_intel *sdw)
{
int ret;
mutex_lock(sdw->link_res->shim_lock);
ret = intel_shim_sync_go_unlocked(sdw);
mutex_unlock(sdw->link_res->shim_lock);
return ret;
}
/*
* PDI routines
*/
static void intel_pdi_init(struct sdw_intel *sdw,
struct sdw_cdns_stream_config *config)
{
void __iomem *shim = sdw->link_res->shim;
unsigned int link_id = sdw->instance;
int pcm_cap, pdm_cap;
/* PCM Stream Capability */
pcm_cap = intel_readw(shim, SDW_SHIM_PCMSCAP(link_id));
config->pcm_bd = FIELD_GET(SDW_SHIM_PCMSCAP_BSS, pcm_cap);
config->pcm_in = FIELD_GET(SDW_SHIM_PCMSCAP_ISS, pcm_cap);
config->pcm_out = FIELD_GET(SDW_SHIM_PCMSCAP_OSS, pcm_cap);
dev_dbg(sdw->cdns.dev, "PCM cap bd:%d in:%d out:%d\n",
config->pcm_bd, config->pcm_in, config->pcm_out);
/* PDM Stream Capability */
pdm_cap = intel_readw(shim, SDW_SHIM_PDMSCAP(link_id));
config->pdm_bd = FIELD_GET(SDW_SHIM_PDMSCAP_BSS, pdm_cap);
config->pdm_in = FIELD_GET(SDW_SHIM_PDMSCAP_ISS, pdm_cap);
config->pdm_out = FIELD_GET(SDW_SHIM_PDMSCAP_OSS, pdm_cap);
dev_dbg(sdw->cdns.dev, "PDM cap bd:%d in:%d out:%d\n",
config->pdm_bd, config->pdm_in, config->pdm_out);
}
static int
intel_pdi_get_ch_cap(struct sdw_intel *sdw, unsigned int pdi_num, bool pcm)
{
void __iomem *shim = sdw->link_res->shim;
unsigned int link_id = sdw->instance;
int count;
if (pcm) {
count = intel_readw(shim, SDW_SHIM_PCMSYCHC(link_id, pdi_num));
/*
* WORKAROUND: on all existing Intel controllers, pdi
* number 2 reports channel count as 1 even though it
* supports 8 channels. Performing hardcoding for pdi
* number 2.
*/
if (pdi_num == 2)
count = 7;
} else {
count = intel_readw(shim, SDW_SHIM_PDMSCAP(link_id));
count = FIELD_GET(SDW_SHIM_PDMSCAP_CPSS, count);
}
/* zero based values for channel count in register */
count++;
return count;
}
static int intel_pdi_get_ch_update(struct sdw_intel *sdw,
struct sdw_cdns_pdi *pdi,
unsigned int num_pdi,
unsigned int *num_ch, bool pcm)
{
int i, ch_count = 0;
for (i = 0; i < num_pdi; i++) {
pdi->ch_count = intel_pdi_get_ch_cap(sdw, pdi->num, pcm);
ch_count += pdi->ch_count;
pdi++;
}
*num_ch = ch_count;
return 0;
}
static int intel_pdi_stream_ch_update(struct sdw_intel *sdw,
struct sdw_cdns_streams *stream, bool pcm)
{
intel_pdi_get_ch_update(sdw, stream->bd, stream->num_bd,
&stream->num_ch_bd, pcm);
intel_pdi_get_ch_update(sdw, stream->in, stream->num_in,
&stream->num_ch_in, pcm);
intel_pdi_get_ch_update(sdw, stream->out, stream->num_out,
&stream->num_ch_out, pcm);
return 0;
}
static int intel_pdi_ch_update(struct sdw_intel *sdw)
{
/* First update PCM streams followed by PDM streams */
intel_pdi_stream_ch_update(sdw, &sdw->cdns.pcm, true);
intel_pdi_stream_ch_update(sdw, &sdw->cdns.pdm, false);
return 0;
}
static void
intel_pdi_shim_configure(struct sdw_intel *sdw, struct sdw_cdns_pdi *pdi)
{
void __iomem *shim = sdw->link_res->shim;
unsigned int link_id = sdw->instance;
int pdi_conf = 0;
/* the Bulk and PCM streams are not contiguous */
pdi->intel_alh_id = (link_id * 16) + pdi->num + 3;
if (pdi->num >= 2)
pdi->intel_alh_id += 2;
/*
* Program stream parameters to stream SHIM register
* This is applicable for PCM stream only.
*/
if (pdi->type != SDW_STREAM_PCM)
return;
if (pdi->dir == SDW_DATA_DIR_RX)
pdi_conf |= SDW_SHIM_PCMSYCM_DIR;
else
pdi_conf &= ~(SDW_SHIM_PCMSYCM_DIR);
u32p_replace_bits(&pdi_conf, pdi->intel_alh_id, SDW_SHIM_PCMSYCM_STREAM);
u32p_replace_bits(&pdi_conf, pdi->l_ch_num, SDW_SHIM_PCMSYCM_LCHN);
u32p_replace_bits(&pdi_conf, pdi->h_ch_num, SDW_SHIM_PCMSYCM_HCHN);
intel_writew(shim, SDW_SHIM_PCMSYCHM(link_id, pdi->num), pdi_conf);
}
static void
intel_pdi_alh_configure(struct sdw_intel *sdw, struct sdw_cdns_pdi *pdi)
{
void __iomem *alh = sdw->link_res->alh;
unsigned int link_id = sdw->instance;
unsigned int conf;
/* the Bulk and PCM streams are not contiguous */
pdi->intel_alh_id = (link_id * 16) + pdi->num + 3;
if (pdi->num >= 2)
pdi->intel_alh_id += 2;
/* Program Stream config ALH register */
conf = intel_readl(alh, SDW_ALH_STRMZCFG(pdi->intel_alh_id));
u32p_replace_bits(&conf, SDW_ALH_STRMZCFG_DMAT_VAL, SDW_ALH_STRMZCFG_DMAT);
u32p_replace_bits(&conf, pdi->ch_count - 1, SDW_ALH_STRMZCFG_CHN);
intel_writel(alh, SDW_ALH_STRMZCFG(pdi->intel_alh_id), conf);
}
static int intel_params_stream(struct sdw_intel *sdw,
struct snd_pcm_substream *substream,
struct snd_soc_dai *dai,
struct snd_pcm_hw_params *hw_params,
int link_id, int alh_stream_id)
{
struct sdw_intel_link_res *res = sdw->link_res;
struct sdw_intel_stream_params_data params_data;
params_data.substream = substream;
params_data.dai = dai;
params_data.hw_params = hw_params;
params_data.link_id = link_id;
params_data.alh_stream_id = alh_stream_id;
if (res->ops && res->ops->params_stream && res->dev)
return res->ops->params_stream(res->dev,
&params_data);
return -EIO;
}
static int intel_free_stream(struct sdw_intel *sdw,
struct snd_pcm_substream *substream,
struct snd_soc_dai *dai,
int link_id)
{
struct sdw_intel_link_res *res = sdw->link_res;
struct sdw_intel_stream_free_data free_data;
free_data.substream = substream;
free_data.dai = dai;
free_data.link_id = link_id;
if (res->ops && res->ops->free_stream && res->dev)
return res->ops->free_stream(res->dev,
&free_data);
return 0;
}
/*
* bank switch routines
*/
static int intel_pre_bank_switch(struct sdw_bus *bus)
{
struct sdw_cdns *cdns = bus_to_cdns(bus);
struct sdw_intel *sdw = cdns_to_intel(cdns);
/* Write to register only for multi-link */
if (!bus->multi_link)
return 0;
intel_shim_sync_arm(sdw);
return 0;
}
static int intel_post_bank_switch(struct sdw_bus *bus)
{
struct sdw_cdns *cdns = bus_to_cdns(bus);
struct sdw_intel *sdw = cdns_to_intel(cdns);
void __iomem *shim = sdw->link_res->shim;
int sync_reg, ret;
/* Write to register only for multi-link */
if (!bus->multi_link)
return 0;
mutex_lock(sdw->link_res->shim_lock);
/* Read SYNC register */
sync_reg = intel_readl(shim, SDW_SHIM_SYNC);
/*
* post_bank_switch() ops is called from the bus in loop for
* all the Masters in the steam with the expectation that
* we trigger the bankswitch for the only first Master in the list
* and do nothing for the other Masters
*
* So, set the SYNCGO bit only if CMDSYNC bit is set for any Master.
*/
if (!(sync_reg & SDW_SHIM_SYNC_CMDSYNC_MASK)) {
ret = 0;
goto unlock;
}
ret = intel_shim_sync_go_unlocked(sdw);
unlock:
mutex_unlock(sdw->link_res->shim_lock);
if (ret < 0)
dev_err(sdw->cdns.dev, "Post bank switch failed: %d\n", ret);
return ret;
}
/*
* DAI routines
*/
static int intel_startup(struct snd_pcm_substream *substream,
struct snd_soc_dai *dai)
{
struct sdw_cdns *cdns = snd_soc_dai_get_drvdata(dai);
int ret;
ret = pm_runtime_get_sync(cdns->dev);
if (ret < 0 && ret != -EACCES) {
dev_err_ratelimited(cdns->dev,
"pm_runtime_get_sync failed in %s, ret %d\n",
__func__, ret);
pm_runtime_put_noidle(cdns->dev);
return ret;
}
return 0;
}
static int intel_hw_params(struct snd_pcm_substream *substream,
struct snd_pcm_hw_params *params,
struct snd_soc_dai *dai)
{
struct sdw_cdns *cdns = snd_soc_dai_get_drvdata(dai);
struct sdw_intel *sdw = cdns_to_intel(cdns);
struct sdw_cdns_dma_data *dma;
struct sdw_cdns_pdi *pdi;
struct sdw_stream_config sconfig;
struct sdw_port_config *pconfig;
int ch, dir;
int ret;
bool pcm = true;
dma = snd_soc_dai_get_dma_data(dai, substream);
if (!dma)
return -EIO;
ch = params_channels(params);
if (substream->stream == SNDRV_PCM_STREAM_CAPTURE)
dir = SDW_DATA_DIR_RX;
else
dir = SDW_DATA_DIR_TX;
if (dma->stream_type == SDW_STREAM_PDM)
pcm = false;
if (pcm)
pdi = sdw_cdns_alloc_pdi(cdns, &cdns->pcm, ch, dir, dai->id);
else
pdi = sdw_cdns_alloc_pdi(cdns, &cdns->pdm, ch, dir, dai->id);
if (!pdi) {
ret = -EINVAL;
goto error;
}
/* do run-time configurations for SHIM, ALH and PDI/PORT */
intel_pdi_shim_configure(sdw, pdi);
intel_pdi_alh_configure(sdw, pdi);
sdw_cdns_config_stream(cdns, ch, dir, pdi);
/* store pdi and hw_params, may be needed in prepare step */
dma->suspended = false;
dma->pdi = pdi;
dma->hw_params = params;
/* Inform DSP about PDI stream number */
ret = intel_params_stream(sdw, substream, dai, params,
sdw->instance,
pdi->intel_alh_id);
if (ret)
goto error;
sconfig.direction = dir;
sconfig.ch_count = ch;
sconfig.frame_rate = params_rate(params);
sconfig.type = dma->stream_type;
if (dma->stream_type == SDW_STREAM_PDM) {
sconfig.frame_rate *= 50;
sconfig.bps = 1;
} else {
sconfig.bps = snd_pcm_format_width(params_format(params));
}
/* Port configuration */
pconfig = kzalloc(sizeof(*pconfig), GFP_KERNEL);
if (!pconfig) {
ret = -ENOMEM;
goto error;
}
pconfig->num = pdi->num;
pconfig->ch_mask = (1 << ch) - 1;
ret = sdw_stream_add_master(&cdns->bus, &sconfig,
pconfig, 1, dma->stream);
if (ret)
dev_err(cdns->dev, "add master to stream failed:%d\n", ret);
kfree(pconfig);
error:
return ret;
}
static int intel_prepare(struct snd_pcm_substream *substream,
struct snd_soc_dai *dai)
{
struct sdw_cdns *cdns = snd_soc_dai_get_drvdata(dai);
struct sdw_intel *sdw = cdns_to_intel(cdns);
struct sdw_cdns_dma_data *dma;
int ch, dir;
int ret = 0;
dma = snd_soc_dai_get_dma_data(dai, substream);
if (!dma) {
dev_err(dai->dev, "failed to get dma data in %s\n",
__func__);
return -EIO;
}
if (dma->suspended) {
dma->suspended = false;
/*
* .prepare() is called after system resume, where we
* need to reinitialize the SHIM/ALH/Cadence IP.
* .prepare() is also called to deal with underflows,
* but in those cases we cannot touch ALH/SHIM
* registers
*/
/* configure stream */
ch = params_channels(dma->hw_params);
if (substream->stream == SNDRV_PCM_STREAM_CAPTURE)
dir = SDW_DATA_DIR_RX;
else
dir = SDW_DATA_DIR_TX;
intel_pdi_shim_configure(sdw, dma->pdi);
intel_pdi_alh_configure(sdw, dma->pdi);
sdw_cdns_config_stream(cdns, ch, dir, dma->pdi);
/* Inform DSP about PDI stream number */
ret = intel_params_stream(sdw, substream, dai,
dma->hw_params,
sdw->instance,
dma->pdi->intel_alh_id);
}
return ret;
}
static int
intel_hw_free(struct snd_pcm_substream *substream, struct snd_soc_dai *dai)
{
struct sdw_cdns *cdns = snd_soc_dai_get_drvdata(dai);
struct sdw_intel *sdw = cdns_to_intel(cdns);
struct sdw_cdns_dma_data *dma;
int ret;
dma = snd_soc_dai_get_dma_data(dai, substream);
if (!dma)
return -EIO;
/*
* The sdw stream state will transition to RELEASED when stream->
* master_list is empty. So the stream state will transition to
* DEPREPARED for the first cpu-dai and to RELEASED for the last
* cpu-dai.
*/
ret = sdw_stream_remove_master(&cdns->bus, dma->stream);
if (ret < 0) {
dev_err(dai->dev, "remove master from stream %s failed: %d\n",
dma->stream->name, ret);
return ret;
}
ret = intel_free_stream(sdw, substream, dai, sdw->instance);
if (ret < 0) {
dev_err(dai->dev, "intel_free_stream: failed %d\n", ret);
return ret;
}
dma->hw_params = NULL;
dma->pdi = NULL;
return 0;
}
static void intel_shutdown(struct snd_pcm_substream *substream,
struct snd_soc_dai *dai)
{
struct sdw_cdns *cdns = snd_soc_dai_get_drvdata(dai);
pm_runtime_mark_last_busy(cdns->dev);
pm_runtime_put_autosuspend(cdns->dev);
}
static int intel_component_dais_suspend(struct snd_soc_component *component)
{
struct sdw_cdns_dma_data *dma;
struct snd_soc_dai *dai;
for_each_component_dais(component, dai) {
/*
* we don't have a .suspend dai_ops, and we don't have access
* to the substream, so let's mark both capture and playback
* DMA contexts as suspended
*/
dma = dai->playback_dma_data;
if (dma)
dma->suspended = true;
dma = dai->capture_dma_data;
if (dma)
dma->suspended = true;
}
return 0;
}
static int intel_pcm_set_sdw_stream(struct snd_soc_dai *dai,
void *stream, int direction)
{
return cdns_set_sdw_stream(dai, stream, true, direction);
}
static int intel_pdm_set_sdw_stream(struct snd_soc_dai *dai,
void *stream, int direction)
{
return cdns_set_sdw_stream(dai, stream, false, direction);
}
static void *intel_get_sdw_stream(struct snd_soc_dai *dai,
int direction)
{
struct sdw_cdns_dma_data *dma;
if (direction == SNDRV_PCM_STREAM_PLAYBACK)
dma = dai->playback_dma_data;
else
dma = dai->capture_dma_data;
if (!dma)
return ERR_PTR(-EINVAL);
return dma->stream;
}
static const struct snd_soc_dai_ops intel_pcm_dai_ops = {
.startup = intel_startup,
.hw_params = intel_hw_params,
.prepare = intel_prepare,
.hw_free = intel_hw_free,
.shutdown = intel_shutdown,
.set_sdw_stream = intel_pcm_set_sdw_stream,
.get_sdw_stream = intel_get_sdw_stream,
};
static const struct snd_soc_dai_ops intel_pdm_dai_ops = {
.startup = intel_startup,
.hw_params = intel_hw_params,
.prepare = intel_prepare,
.hw_free = intel_hw_free,
.shutdown = intel_shutdown,
.set_sdw_stream = intel_pdm_set_sdw_stream,
.get_sdw_stream = intel_get_sdw_stream,
};
static const struct snd_soc_component_driver dai_component = {
.name = "soundwire",
.suspend = intel_component_dais_suspend
};
static int intel_create_dai(struct sdw_cdns *cdns,
struct snd_soc_dai_driver *dais,
enum intel_pdi_type type,
u32 num, u32 off, u32 max_ch, bool pcm)
{
int i;
if (num == 0)
return 0;
/* TODO: Read supported rates/formats from hardware */
for (i = off; i < (off + num); i++) {
dais[i].name = devm_kasprintf(cdns->dev, GFP_KERNEL,
"SDW%d Pin%d",
cdns->instance, i);
if (!dais[i].name)
return -ENOMEM;
if (type == INTEL_PDI_BD || type == INTEL_PDI_OUT) {
dais[i].playback.channels_min = 1;
dais[i].playback.channels_max = max_ch;
dais[i].playback.rates = SNDRV_PCM_RATE_48000;
dais[i].playback.formats = SNDRV_PCM_FMTBIT_S16_LE;
}
if (type == INTEL_PDI_BD || type == INTEL_PDI_IN) {
dais[i].capture.channels_min = 1;
dais[i].capture.channels_max = max_ch;
dais[i].capture.rates = SNDRV_PCM_RATE_48000;
dais[i].capture.formats = SNDRV_PCM_FMTBIT_S16_LE;
}
if (pcm)
dais[i].ops = &intel_pcm_dai_ops;
else
dais[i].ops = &intel_pdm_dai_ops;
}
return 0;
}
static int intel_register_dai(struct sdw_intel *sdw)
{
struct sdw_cdns *cdns = &sdw->cdns;
struct sdw_cdns_streams *stream;
struct snd_soc_dai_driver *dais;
int num_dai, ret, off = 0;
/* DAIs are created based on total number of PDIs supported */
num_dai = cdns->pcm.num_pdi + cdns->pdm.num_pdi;
dais = devm_kcalloc(cdns->dev, num_dai, sizeof(*dais), GFP_KERNEL);
if (!dais)
return -ENOMEM;
/* Create PCM DAIs */
stream = &cdns->pcm;
ret = intel_create_dai(cdns, dais, INTEL_PDI_IN, cdns->pcm.num_in,
off, stream->num_ch_in, true);
if (ret)
return ret;
off += cdns->pcm.num_in;
ret = intel_create_dai(cdns, dais, INTEL_PDI_OUT, cdns->pcm.num_out,
off, stream->num_ch_out, true);
if (ret)
return ret;
off += cdns->pcm.num_out;
ret = intel_create_dai(cdns, dais, INTEL_PDI_BD, cdns->pcm.num_bd,
off, stream->num_ch_bd, true);
if (ret)
return ret;
/* Create PDM DAIs */
stream = &cdns->pdm;
off += cdns->pcm.num_bd;
ret = intel_create_dai(cdns, dais, INTEL_PDI_IN, cdns->pdm.num_in,
off, stream->num_ch_in, false);
if (ret)
return ret;
off += cdns->pdm.num_in;
ret = intel_create_dai(cdns, dais, INTEL_PDI_OUT, cdns->pdm.num_out,
off, stream->num_ch_out, false);
if (ret)
return ret;
off += cdns->pdm.num_out;
ret = intel_create_dai(cdns, dais, INTEL_PDI_BD, cdns->pdm.num_bd,
off, stream->num_ch_bd, false);
if (ret)
return ret;
return snd_soc_register_component(cdns->dev, &dai_component,
dais, num_dai);
}
static int sdw_master_read_intel_prop(struct sdw_bus *bus)
{
struct sdw_master_prop *prop = &bus->prop;
struct fwnode_handle *link;
char name[32];
u32 quirk_mask;
/* Find master handle */
snprintf(name, sizeof(name),
"mipi-sdw-link-%d-subproperties", bus->link_id);
link = device_get_named_child_node(bus->dev, name);
if (!link) {
dev_err(bus->dev, "Master node %s not found\n", name);
return -EIO;
}
fwnode_property_read_u32(link,
"intel-sdw-ip-clock",
&prop->mclk_freq);
/* the values reported by BIOS are the 2x clock, not the bus clock */
prop->mclk_freq /= 2;
fwnode_property_read_u32(link,
"intel-quirk-mask",
&quirk_mask);
if (quirk_mask & SDW_INTEL_QUIRK_MASK_BUS_DISABLE)
prop->hw_disabled = true;
prop->quirks = SDW_MASTER_QUIRKS_CLEAR_INITIAL_CLASH |
SDW_MASTER_QUIRKS_CLEAR_INITIAL_PARITY;
return 0;
}
static int intel_prop_read(struct sdw_bus *bus)
{
/* Initialize with default handler to read all DisCo properties */
sdw_master_read_prop(bus);
/* read Intel-specific properties */
sdw_master_read_intel_prop(bus);
return 0;
}
static struct sdw_master_ops sdw_intel_ops = {
.read_prop = sdw_master_read_prop,
.override_adr = sdw_dmi_override_adr,
.xfer_msg = cdns_xfer_msg,
.xfer_msg_defer = cdns_xfer_msg_defer,
.reset_page_addr = cdns_reset_page_addr,
.set_bus_conf = cdns_bus_conf,
.pre_bank_switch = intel_pre_bank_switch,
.post_bank_switch = intel_post_bank_switch,
};
static int intel_init(struct sdw_intel *sdw)
{
bool clock_stop;
/* Initialize shim and controller */
intel_link_power_up(sdw);
clock_stop = sdw_cdns_is_clock_stop(&sdw->cdns);
intel_shim_init(sdw, clock_stop);
return 0;
}
/*
* probe and init (aux_dev_id argument is required by function prototype but not used)
*/
static int intel_link_probe(struct auxiliary_device *auxdev,
const struct auxiliary_device_id *aux_dev_id)
{
struct device *dev = &auxdev->dev;
struct sdw_intel_link_dev *ldev = auxiliary_dev_to_sdw_intel_link_dev(auxdev);
struct sdw_intel *sdw;
struct sdw_cdns *cdns;
struct sdw_bus *bus;
int ret;
sdw = devm_kzalloc(dev, sizeof(*sdw), GFP_KERNEL);
if (!sdw)
return -ENOMEM;
cdns = &sdw->cdns;
bus = &cdns->bus;
sdw->instance = auxdev->id;
sdw->link_res = &ldev->link_res;
cdns->dev = dev;
cdns->registers = sdw->link_res->registers;
cdns->instance = sdw->instance;
cdns->msg_count = 0;
bus->link_id = auxdev->id;
sdw_cdns_probe(cdns);
/* Set property read ops */
sdw_intel_ops.read_prop = intel_prop_read;
bus->ops = &sdw_intel_ops;
/* set driver data, accessed by snd_soc_dai_get_drvdata() */
dev_set_drvdata(dev, cdns);
/* use generic bandwidth allocation algorithm */
sdw->cdns.bus.compute_params = sdw_compute_params;
ret = sdw_bus_master_add(bus, dev, dev->fwnode);
if (ret) {
dev_err(dev, "sdw_bus_master_add fail: %d\n", ret);
return ret;
}
if (bus->prop.hw_disabled)
dev_info(dev,
"SoundWire master %d is disabled, will be ignored\n",
bus->link_id);
/*
* Ignore BIOS err_threshold, it's a really bad idea when dealing
* with multiple hardware synchronized links
*/
bus->prop.err_threshold = 0;
return 0;
}
int intel_link_startup(struct auxiliary_device *auxdev)
{
struct sdw_cdns_stream_config config;
struct device *dev = &auxdev->dev;
struct sdw_cdns *cdns = dev_get_drvdata(dev);
struct sdw_intel *sdw = cdns_to_intel(cdns);
struct sdw_bus *bus = &cdns->bus;
int link_flags;
bool multi_link;
u32 clock_stop_quirks;
int ret;
if (bus->prop.hw_disabled) {
dev_info(dev,
"SoundWire master %d is disabled, ignoring\n",
sdw->instance);
return 0;
}
link_flags = md_flags >> (bus->link_id * 8);
multi_link = !(link_flags & SDW_INTEL_MASTER_DISABLE_MULTI_LINK);
if (!multi_link) {
dev_dbg(dev, "Multi-link is disabled\n");
bus->multi_link = false;
} else {
/*
* hardware-based synchronization is required regardless
* of the number of segments used by a stream: SSP-based
* synchronization is gated by gsync when the multi-master
* mode is set.
*/
bus->multi_link = true;
bus->hw_sync_min_links = 1;
}
/* Initialize shim, controller */
ret = intel_init(sdw);
if (ret)
goto err_init;
/* Read the PDI config and initialize cadence PDI */
intel_pdi_init(sdw, &config);
ret = sdw_cdns_pdi_init(cdns, config);
if (ret)
goto err_init;
intel_pdi_ch_update(sdw);
ret = sdw_cdns_enable_interrupt(cdns, true);
if (ret < 0) {
dev_err(dev, "cannot enable interrupts\n");
goto err_init;
}
/*
* follow recommended programming flows to avoid timeouts when
* gsync is enabled
*/
if (multi_link)
intel_shim_sync_arm(sdw);
ret = sdw_cdns_init(cdns);
if (ret < 0) {
dev_err(dev, "unable to initialize Cadence IP\n");
goto err_interrupt;
}
ret = sdw_cdns_exit_reset(cdns);
if (ret < 0) {
dev_err(dev, "unable to exit bus reset sequence\n");
goto err_interrupt;
}
if (multi_link) {
ret = intel_shim_sync_go(sdw);
if (ret < 0) {
dev_err(dev, "sync go failed: %d\n", ret);
goto err_interrupt;
}
}
soundwire: cadence: add paranoid check on self-clearing bits The Cadence IP exposes a small number of self-clearing bits in the MCP_CONTROL and MCP_CONFIG_UPDATE registers. We currently do not check that those bits are indeed cleared, e.g. during resume operations. That could lead to resuming peripheral devices too early. In addition, if we happen to read these registers, update one of the fields and write the register back, we may be writing stale data that might have been cleared in hardware. These sort of race conditions could lead to e.g. doing a hw_reset twice or stopping a clock that just restarted. There is no clear way of avoiding these potential race conditions other than making sure that these registers fields are cleared before any read-modify-write sequence. If we detect this sort of errors, we only log them since there is no clear recovery possible. The only way out is likely to restart the IP with a suspend/resume cycle. Note that the checks are performed before updating the registers, as well as after the Intel 'sync go' sequence in multi-link mode. That should cover both the start and end of suspend/resume hardware configurations. The Multi-Master mode gates the configuration updates until the 'sync go' signal is asserted, so we only check on init and after the end of the 'sync go' sequence. The duration of the usleep_range() was defined by the GSYNC frequency used in multi-master mode. With a 4kHz frequency, any configuration change might be deferred by up to 250us. Extending the range to 1000-1500us should guarantee that the configuration change is completed without any significant impact on the overall resume time. Suggested-by: Bard Liao <yung-chuan.liao@linux.intel.com> Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com> Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com> Link: https://lore.kernel.org/r/20210714051349.13064-1-yung-chuan.liao@linux.intel.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
2021-07-14 13:13:49 +08:00
sdw_cdns_check_self_clearing_bits(cdns, __func__,
true, INTEL_MASTER_RESET_ITERATIONS);
/* Register DAIs */
ret = intel_register_dai(sdw);
if (ret) {
dev_err(dev, "DAI registration failed: %d\n", ret);
snd_soc_unregister_component(dev);
goto err_interrupt;
}
intel_debugfs_init(sdw);
/* Enable runtime PM */
if (!(link_flags & SDW_INTEL_MASTER_DISABLE_PM_RUNTIME)) {
pm_runtime_set_autosuspend_delay(dev,
INTEL_MASTER_SUSPEND_DELAY_MS);
pm_runtime_use_autosuspend(dev);
pm_runtime_mark_last_busy(dev);
pm_runtime_set_active(dev);
pm_runtime_enable(dev);
}
clock_stop_quirks = sdw->link_res->clock_stop_quirks;
if (clock_stop_quirks & SDW_INTEL_CLK_STOP_NOT_ALLOWED) {
/*
* To keep the clock running we need to prevent
* pm_runtime suspend from happening by increasing the
* reference count.
* This quirk is specified by the parent PCI device in
* case of specific latency requirements. It will have
* no effect if pm_runtime is disabled by the user via
* a module parameter for testing purposes.
*/
pm_runtime_get_noresume(dev);
}
/*
* The runtime PM status of Slave devices is "Unsupported"
* until they report as ATTACHED. If they don't, e.g. because
* there are no Slave devices populated or if the power-on is
* delayed or dependent on a power switch, the Master will
* remain active and prevent its parent from suspending.
*
* Conditionally force the pm_runtime core to re-evaluate the
* Master status in the absence of any Slave activity. A quirk
* is provided to e.g. deal with Slaves that may be powered on
* with a delay. A more complete solution would require the
* definition of Master properties.
*/
if (!(link_flags & SDW_INTEL_MASTER_DISABLE_PM_RUNTIME_IDLE))
pm_runtime_idle(dev);
soundwire: intel: skip suspend/resume/wake when link was not started The SoundWire Linux devices are created purely based on information provided by platform firmware (e.g. ACPI DSDT table). When the kernel finds a matching driver for the device address (_ADR), the probe will initialize required data structures and initialize pm ops. When the SoundWire link is started at a later point, the physical devices will synchronize on the SoundWire frames and report their attachment status, thereby triggering the enumeration and initialization of device registers. This two-step solution was a conscious design decision to allow e.g. a driver to use sideband mechanisms to turn power rails on. This can also allow OEMs to describe multiple platforms with the same DSDT table, the devices that are not physically present in hardware. The drawback of this approach is a bit of confusion, with more devices than are actually present in hardware. This results in 'ghost' devices, for which the driver successfully probes, but that will not generate any traffic on the bus. suspend-resume transitions are handled by drivers, and skipped when the devices are not physically present. This patch provides a work-around for a second-level of confusion in platform firmware: some platforms only use HDaudio links, but nevertheless expose SoundWire 'ghost' devices. This results in error messages in the Intel driver while trying to suspend/resume these links. The simplest solution is to add a boolean status flag to skip all suspend/resume/wake sequences if the link was never started. Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com> Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com> Link: https://lore.kernel.org/r/20210818024954.16873-3-yung-chuan.liao@linux.intel.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
2021-08-18 10:49:53 +08:00
sdw->startup_done = true;
return 0;
err_interrupt:
sdw_cdns_enable_interrupt(cdns, false);
err_init:
return ret;
}
static void intel_link_remove(struct auxiliary_device *auxdev)
{
struct device *dev = &auxdev->dev;
struct sdw_cdns *cdns = dev_get_drvdata(dev);
struct sdw_intel *sdw = cdns_to_intel(cdns);
struct sdw_bus *bus = &cdns->bus;
/*
* Since pm_runtime is already disabled, we don't decrease
* the refcount when the clock_stop_quirk is
* SDW_INTEL_CLK_STOP_NOT_ALLOWED
*/
if (!bus->prop.hw_disabled) {
intel_debugfs_exit(sdw);
sdw_cdns_enable_interrupt(cdns, false);
snd_soc_unregister_component(dev);
}
sdw_bus_master_delete(bus);
}
int intel_link_process_wakeen_event(struct auxiliary_device *auxdev)
{
struct device *dev = &auxdev->dev;
struct sdw_intel *sdw;
struct sdw_bus *bus;
void __iomem *shim;
u16 wake_sts;
sdw = dev_get_drvdata(dev);
bus = &sdw->cdns.bus;
soundwire: intel: skip suspend/resume/wake when link was not started The SoundWire Linux devices are created purely based on information provided by platform firmware (e.g. ACPI DSDT table). When the kernel finds a matching driver for the device address (_ADR), the probe will initialize required data structures and initialize pm ops. When the SoundWire link is started at a later point, the physical devices will synchronize on the SoundWire frames and report their attachment status, thereby triggering the enumeration and initialization of device registers. This two-step solution was a conscious design decision to allow e.g. a driver to use sideband mechanisms to turn power rails on. This can also allow OEMs to describe multiple platforms with the same DSDT table, the devices that are not physically present in hardware. The drawback of this approach is a bit of confusion, with more devices than are actually present in hardware. This results in 'ghost' devices, for which the driver successfully probes, but that will not generate any traffic on the bus. suspend-resume transitions are handled by drivers, and skipped when the devices are not physically present. This patch provides a work-around for a second-level of confusion in platform firmware: some platforms only use HDaudio links, but nevertheless expose SoundWire 'ghost' devices. This results in error messages in the Intel driver while trying to suspend/resume these links. The simplest solution is to add a boolean status flag to skip all suspend/resume/wake sequences if the link was never started. Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com> Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com> Link: https://lore.kernel.org/r/20210818024954.16873-3-yung-chuan.liao@linux.intel.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
2021-08-18 10:49:53 +08:00
if (bus->prop.hw_disabled || !sdw->startup_done) {
dev_dbg(dev, "SoundWire master %d is disabled or not-started, ignoring\n",
bus->link_id);
return 0;
}
shim = sdw->link_res->shim;
wake_sts = intel_readw(shim, SDW_SHIM_WAKESTS);
if (!(wake_sts & BIT(sdw->instance)))
return 0;
/* disable WAKEEN interrupt ASAP to prevent interrupt flood */
intel_shim_wake(sdw, false);
/*
* resume the Master, which will generate a bus reset and result in
* Slaves re-attaching and be re-enumerated. The SoundWire physical
* device which generated the wake will trigger an interrupt, which
* will in turn cause the corresponding Linux Slave device to be
* resumed and the Slave codec driver to check the status.
*/
pm_request_resume(dev);
return 0;
}
/*
* PM calls
*/
soundwire: intel: conditionally exit clock stop mode on system suspend Intel stress tests reported issues with the clock stop mode, specifically when trying to do a system suspend while the link is already pm_runtime suspended. In this case, we need to disable the shim wake, but when the PCI parent device is also pm_runtime suspended the SHIM registers are not accessible. Since this is an invalid corner case, this patch suggests a pm_runtime resume of the entire bus to full power (parent+child devices) before the system suspend so that the shim wake can be disabled. Unlike the suspend operation, the .prepare callbacks are propagated from root device to leaf devices. By adding a .prepare callback at the SoundWire link level, we can double-check the pm_runtime status of the device as well as its parent PCI device. When the problematic configuration is detected, the device is pm_runtime resumed - which by construction also resume its parent. An additional loop is added to resume all child devices. In theory we only need to restart the link, but doing so will also cause the physical devices to synchronize and re-initialize, while their Linux devices remain pm_runtime suspended. It's simpler to make sure the codec devices are fully resumed so that we don't have to deal with zombie states. This additional loop could have been avoided by adding a .prepare callback in SoundWire codec drivers. Functionally this would have been equivalent. The rationale for implementing a loop at the link level is only to reduce the amount of code required to deal at the codec level with an Intel corner case - in other words keep codec drivers independent from Intel platform-specific programming sequences. BugLink: https://github.com/thesofproject/linux/issues/2606 Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com> Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com> Link: https://lore.kernel.org/r/20210818024954.16873-4-yung-chuan.liao@linux.intel.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
2021-08-18 10:49:54 +08:00
static int intel_resume_child_device(struct device *dev, void *data)
{
int ret;
struct sdw_slave *slave = dev_to_sdw_dev(dev);
if (!slave->probed) {
dev_dbg(dev, "%s: skipping device, no probed driver\n", __func__);
return 0;
}
if (!slave->dev_num_sticky) {
dev_dbg(dev, "%s: skipping device, never detected on bus\n", __func__);
return 0;
}
ret = pm_request_resume(dev);
if (ret < 0)
dev_err(dev, "%s: pm_request_resume failed: %d\n", __func__, ret);
return ret;
}
static int __maybe_unused intel_pm_prepare(struct device *dev)
{
struct sdw_cdns *cdns = dev_get_drvdata(dev);
struct sdw_intel *sdw = cdns_to_intel(cdns);
struct sdw_bus *bus = &cdns->bus;
u32 clock_stop_quirks;
int ret = 0;
if (bus->prop.hw_disabled || !sdw->startup_done) {
dev_dbg(dev, "SoundWire master %d is disabled or not-started, ignoring\n",
bus->link_id);
return 0;
}
clock_stop_quirks = sdw->link_res->clock_stop_quirks;
if (pm_runtime_suspended(dev) &&
pm_runtime_suspended(dev->parent) &&
((clock_stop_quirks & SDW_INTEL_CLK_STOP_BUS_RESET) ||
!clock_stop_quirks)) {
/*
* if we've enabled clock stop, and the parent is suspended, the SHIM registers
* are not accessible and the shim wake cannot be disabled.
* The only solution is to resume the entire bus to full power
*/
/*
* If any operation in this block fails, we keep going since we don't want
* to prevent system suspend from happening and errors should be recoverable
* on resume.
*/
/*
* first resume the device for this link. This will also by construction
* resume the PCI parent device.
*/
ret = pm_request_resume(dev);
if (ret < 0) {
dev_err(dev, "%s: pm_request_resume failed: %d\n", __func__, ret);
return 0;
}
/*
* Continue resuming the entire bus (parent + child devices) to exit
* the clock stop mode. If there are no devices connected on this link
* this is a no-op.
* The resume to full power could have been implemented with a .prepare
* step in SoundWire codec drivers. This would however require a lot
* of code to handle an Intel-specific corner case. It is simpler in
* practice to add a loop at the link level.
*/
ret = device_for_each_child(bus->dev, NULL, intel_resume_child_device);
if (ret < 0)
dev_err(dev, "%s: intel_resume_child_device failed: %d\n", __func__, ret);
}
return 0;
}
static int __maybe_unused intel_suspend(struct device *dev)
{
struct sdw_cdns *cdns = dev_get_drvdata(dev);
struct sdw_intel *sdw = cdns_to_intel(cdns);
struct sdw_bus *bus = &cdns->bus;
u32 clock_stop_quirks;
int ret;
soundwire: intel: skip suspend/resume/wake when link was not started The SoundWire Linux devices are created purely based on information provided by platform firmware (e.g. ACPI DSDT table). When the kernel finds a matching driver for the device address (_ADR), the probe will initialize required data structures and initialize pm ops. When the SoundWire link is started at a later point, the physical devices will synchronize on the SoundWire frames and report their attachment status, thereby triggering the enumeration and initialization of device registers. This two-step solution was a conscious design decision to allow e.g. a driver to use sideband mechanisms to turn power rails on. This can also allow OEMs to describe multiple platforms with the same DSDT table, the devices that are not physically present in hardware. The drawback of this approach is a bit of confusion, with more devices than are actually present in hardware. This results in 'ghost' devices, for which the driver successfully probes, but that will not generate any traffic on the bus. suspend-resume transitions are handled by drivers, and skipped when the devices are not physically present. This patch provides a work-around for a second-level of confusion in platform firmware: some platforms only use HDaudio links, but nevertheless expose SoundWire 'ghost' devices. This results in error messages in the Intel driver while trying to suspend/resume these links. The simplest solution is to add a boolean status flag to skip all suspend/resume/wake sequences if the link was never started. Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com> Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com> Link: https://lore.kernel.org/r/20210818024954.16873-3-yung-chuan.liao@linux.intel.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
2021-08-18 10:49:53 +08:00
if (bus->prop.hw_disabled || !sdw->startup_done) {
dev_dbg(dev, "SoundWire master %d is disabled or not-started, ignoring\n",
bus->link_id);
return 0;
}
if (pm_runtime_suspended(dev)) {
dev_dbg(dev, "%s: pm_runtime status: suspended\n", __func__);
clock_stop_quirks = sdw->link_res->clock_stop_quirks;
soundwire: intel: conditionally exit clock stop mode on system suspend Intel stress tests reported issues with the clock stop mode, specifically when trying to do a system suspend while the link is already pm_runtime suspended. In this case, we need to disable the shim wake, but when the PCI parent device is also pm_runtime suspended the SHIM registers are not accessible. Since this is an invalid corner case, this patch suggests a pm_runtime resume of the entire bus to full power (parent+child devices) before the system suspend so that the shim wake can be disabled. Unlike the suspend operation, the .prepare callbacks are propagated from root device to leaf devices. By adding a .prepare callback at the SoundWire link level, we can double-check the pm_runtime status of the device as well as its parent PCI device. When the problematic configuration is detected, the device is pm_runtime resumed - which by construction also resume its parent. An additional loop is added to resume all child devices. In theory we only need to restart the link, but doing so will also cause the physical devices to synchronize and re-initialize, while their Linux devices remain pm_runtime suspended. It's simpler to make sure the codec devices are fully resumed so that we don't have to deal with zombie states. This additional loop could have been avoided by adding a .prepare callback in SoundWire codec drivers. Functionally this would have been equivalent. The rationale for implementing a loop at the link level is only to reduce the amount of code required to deal at the codec level with an Intel corner case - in other words keep codec drivers independent from Intel platform-specific programming sequences. BugLink: https://github.com/thesofproject/linux/issues/2606 Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com> Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com> Link: https://lore.kernel.org/r/20210818024954.16873-4-yung-chuan.liao@linux.intel.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
2021-08-18 10:49:54 +08:00
if ((clock_stop_quirks & SDW_INTEL_CLK_STOP_BUS_RESET) ||
!clock_stop_quirks) {
if (pm_runtime_suspended(dev->parent)) {
/*
* paranoia check: this should not happen with the .prepare
* resume to full power
*/
dev_err(dev, "%s: invalid config: parent is suspended\n", __func__);
} else {
intel_shim_wake(sdw, false);
}
}
return 0;
}
ret = sdw_cdns_enable_interrupt(cdns, false);
if (ret < 0) {
dev_err(dev, "cannot disable interrupts on suspend\n");
return ret;
}
ret = intel_link_power_down(sdw);
if (ret) {
dev_err(dev, "Link power down failed: %d\n", ret);
return ret;
}
intel_shim_wake(sdw, false);
return 0;
}
static int __maybe_unused intel_suspend_runtime(struct device *dev)
{
struct sdw_cdns *cdns = dev_get_drvdata(dev);
struct sdw_intel *sdw = cdns_to_intel(cdns);
struct sdw_bus *bus = &cdns->bus;
u32 clock_stop_quirks;
int ret;
soundwire: intel: skip suspend/resume/wake when link was not started The SoundWire Linux devices are created purely based on information provided by platform firmware (e.g. ACPI DSDT table). When the kernel finds a matching driver for the device address (_ADR), the probe will initialize required data structures and initialize pm ops. When the SoundWire link is started at a later point, the physical devices will synchronize on the SoundWire frames and report their attachment status, thereby triggering the enumeration and initialization of device registers. This two-step solution was a conscious design decision to allow e.g. a driver to use sideband mechanisms to turn power rails on. This can also allow OEMs to describe multiple platforms with the same DSDT table, the devices that are not physically present in hardware. The drawback of this approach is a bit of confusion, with more devices than are actually present in hardware. This results in 'ghost' devices, for which the driver successfully probes, but that will not generate any traffic on the bus. suspend-resume transitions are handled by drivers, and skipped when the devices are not physically present. This patch provides a work-around for a second-level of confusion in platform firmware: some platforms only use HDaudio links, but nevertheless expose SoundWire 'ghost' devices. This results in error messages in the Intel driver while trying to suspend/resume these links. The simplest solution is to add a boolean status flag to skip all suspend/resume/wake sequences if the link was never started. Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com> Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com> Link: https://lore.kernel.org/r/20210818024954.16873-3-yung-chuan.liao@linux.intel.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
2021-08-18 10:49:53 +08:00
if (bus->prop.hw_disabled || !sdw->startup_done) {
dev_dbg(dev, "SoundWire master %d is disabled or not-started, ignoring\n",
bus->link_id);
return 0;
}
clock_stop_quirks = sdw->link_res->clock_stop_quirks;
if (clock_stop_quirks & SDW_INTEL_CLK_STOP_TEARDOWN) {
ret = sdw_cdns_enable_interrupt(cdns, false);
if (ret < 0) {
dev_err(dev, "cannot disable interrupts on suspend\n");
return ret;
}
ret = intel_link_power_down(sdw);
if (ret) {
dev_err(dev, "Link power down failed: %d\n", ret);
return ret;
}
intel_shim_wake(sdw, false);
} else if (clock_stop_quirks & SDW_INTEL_CLK_STOP_BUS_RESET ||
!clock_stop_quirks) {
bool wake_enable = true;
ret = sdw_cdns_clock_stop(cdns, true);
if (ret < 0) {
dev_err(dev, "cannot enable clock stop on suspend\n");
wake_enable = false;
}
ret = sdw_cdns_enable_interrupt(cdns, false);
if (ret < 0) {
dev_err(dev, "cannot disable interrupts on suspend\n");
return ret;
}
ret = intel_link_power_down(sdw);
if (ret) {
dev_err(dev, "Link power down failed: %d\n", ret);
return ret;
}
intel_shim_wake(sdw, wake_enable);
} else {
dev_err(dev, "%s clock_stop_quirks %x unsupported\n",
__func__, clock_stop_quirks);
ret = -EINVAL;
}
return ret;
}
static int __maybe_unused intel_resume(struct device *dev)
{
struct sdw_cdns *cdns = dev_get_drvdata(dev);
struct sdw_intel *sdw = cdns_to_intel(cdns);
struct sdw_bus *bus = &cdns->bus;
int link_flags;
bool multi_link;
int ret;
soundwire: intel: skip suspend/resume/wake when link was not started The SoundWire Linux devices are created purely based on information provided by platform firmware (e.g. ACPI DSDT table). When the kernel finds a matching driver for the device address (_ADR), the probe will initialize required data structures and initialize pm ops. When the SoundWire link is started at a later point, the physical devices will synchronize on the SoundWire frames and report their attachment status, thereby triggering the enumeration and initialization of device registers. This two-step solution was a conscious design decision to allow e.g. a driver to use sideband mechanisms to turn power rails on. This can also allow OEMs to describe multiple platforms with the same DSDT table, the devices that are not physically present in hardware. The drawback of this approach is a bit of confusion, with more devices than are actually present in hardware. This results in 'ghost' devices, for which the driver successfully probes, but that will not generate any traffic on the bus. suspend-resume transitions are handled by drivers, and skipped when the devices are not physically present. This patch provides a work-around for a second-level of confusion in platform firmware: some platforms only use HDaudio links, but nevertheless expose SoundWire 'ghost' devices. This results in error messages in the Intel driver while trying to suspend/resume these links. The simplest solution is to add a boolean status flag to skip all suspend/resume/wake sequences if the link was never started. Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com> Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com> Link: https://lore.kernel.org/r/20210818024954.16873-3-yung-chuan.liao@linux.intel.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
2021-08-18 10:49:53 +08:00
if (bus->prop.hw_disabled || !sdw->startup_done) {
dev_dbg(dev, "SoundWire master %d is disabled or not-started, ignoring\n",
bus->link_id);
return 0;
}
link_flags = md_flags >> (bus->link_id * 8);
multi_link = !(link_flags & SDW_INTEL_MASTER_DISABLE_MULTI_LINK);
if (pm_runtime_suspended(dev)) {
dev_dbg(dev, "%s: pm_runtime status was suspended, forcing active\n", __func__);
/* follow required sequence from runtime_pm.rst */
pm_runtime_disable(dev);
pm_runtime_set_active(dev);
pm_runtime_mark_last_busy(dev);
pm_runtime_enable(dev);
link_flags = md_flags >> (bus->link_id * 8);
if (!(link_flags & SDW_INTEL_MASTER_DISABLE_PM_RUNTIME_IDLE))
pm_runtime_idle(dev);
}
ret = intel_init(sdw);
if (ret) {
dev_err(dev, "%s failed: %d\n", __func__, ret);
return ret;
}
/*
* make sure all Slaves are tagged as UNATTACHED and provide
* reason for reinitialization
*/
sdw_clear_slave_status(bus, SDW_UNATTACH_REQUEST_MASTER_RESET);
ret = sdw_cdns_enable_interrupt(cdns, true);
if (ret < 0) {
dev_err(dev, "cannot enable interrupts during resume\n");
return ret;
}
/*
* follow recommended programming flows to avoid timeouts when
* gsync is enabled
*/
if (multi_link)
intel_shim_sync_arm(sdw);
ret = sdw_cdns_init(&sdw->cdns);
if (ret < 0) {
dev_err(dev, "unable to initialize Cadence IP during resume\n");
return ret;
}
ret = sdw_cdns_exit_reset(cdns);
if (ret < 0) {
dev_err(dev, "unable to exit bus reset sequence during resume\n");
return ret;
}
if (multi_link) {
ret = intel_shim_sync_go(sdw);
if (ret < 0) {
dev_err(dev, "sync go failed during resume\n");
return ret;
}
}
soundwire: cadence: add paranoid check on self-clearing bits The Cadence IP exposes a small number of self-clearing bits in the MCP_CONTROL and MCP_CONFIG_UPDATE registers. We currently do not check that those bits are indeed cleared, e.g. during resume operations. That could lead to resuming peripheral devices too early. In addition, if we happen to read these registers, update one of the fields and write the register back, we may be writing stale data that might have been cleared in hardware. These sort of race conditions could lead to e.g. doing a hw_reset twice or stopping a clock that just restarted. There is no clear way of avoiding these potential race conditions other than making sure that these registers fields are cleared before any read-modify-write sequence. If we detect this sort of errors, we only log them since there is no clear recovery possible. The only way out is likely to restart the IP with a suspend/resume cycle. Note that the checks are performed before updating the registers, as well as after the Intel 'sync go' sequence in multi-link mode. That should cover both the start and end of suspend/resume hardware configurations. The Multi-Master mode gates the configuration updates until the 'sync go' signal is asserted, so we only check on init and after the end of the 'sync go' sequence. The duration of the usleep_range() was defined by the GSYNC frequency used in multi-master mode. With a 4kHz frequency, any configuration change might be deferred by up to 250us. Extending the range to 1000-1500us should guarantee that the configuration change is completed without any significant impact on the overall resume time. Suggested-by: Bard Liao <yung-chuan.liao@linux.intel.com> Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com> Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com> Link: https://lore.kernel.org/r/20210714051349.13064-1-yung-chuan.liao@linux.intel.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
2021-07-14 13:13:49 +08:00
sdw_cdns_check_self_clearing_bits(cdns, __func__,
true, INTEL_MASTER_RESET_ITERATIONS);
/*
* after system resume, the pm_runtime suspend() may kick in
* during the enumeration, before any children device force the
* master device to remain active. Using pm_runtime_get()
* routines is not really possible, since it'd prevent the
* master from suspending.
* A reasonable compromise is to update the pm_runtime
* counters and delay the pm_runtime suspend by several
* seconds, by when all enumeration should be complete.
*/
pm_runtime_mark_last_busy(dev);
return ret;
}
static int __maybe_unused intel_resume_runtime(struct device *dev)
{
struct sdw_cdns *cdns = dev_get_drvdata(dev);
struct sdw_intel *sdw = cdns_to_intel(cdns);
struct sdw_bus *bus = &cdns->bus;
u32 clock_stop_quirks;
bool clock_stop0;
int link_flags;
bool multi_link;
int status;
int ret;
soundwire: intel: skip suspend/resume/wake when link was not started The SoundWire Linux devices are created purely based on information provided by platform firmware (e.g. ACPI DSDT table). When the kernel finds a matching driver for the device address (_ADR), the probe will initialize required data structures and initialize pm ops. When the SoundWire link is started at a later point, the physical devices will synchronize on the SoundWire frames and report their attachment status, thereby triggering the enumeration and initialization of device registers. This two-step solution was a conscious design decision to allow e.g. a driver to use sideband mechanisms to turn power rails on. This can also allow OEMs to describe multiple platforms with the same DSDT table, the devices that are not physically present in hardware. The drawback of this approach is a bit of confusion, with more devices than are actually present in hardware. This results in 'ghost' devices, for which the driver successfully probes, but that will not generate any traffic on the bus. suspend-resume transitions are handled by drivers, and skipped when the devices are not physically present. This patch provides a work-around for a second-level of confusion in platform firmware: some platforms only use HDaudio links, but nevertheless expose SoundWire 'ghost' devices. This results in error messages in the Intel driver while trying to suspend/resume these links. The simplest solution is to add a boolean status flag to skip all suspend/resume/wake sequences if the link was never started. Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com> Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com> Link: https://lore.kernel.org/r/20210818024954.16873-3-yung-chuan.liao@linux.intel.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
2021-08-18 10:49:53 +08:00
if (bus->prop.hw_disabled || !sdw->startup_done) {
dev_dbg(dev, "SoundWire master %d is disabled or not-started, ignoring\n",
bus->link_id);
return 0;
}
link_flags = md_flags >> (bus->link_id * 8);
multi_link = !(link_flags & SDW_INTEL_MASTER_DISABLE_MULTI_LINK);
clock_stop_quirks = sdw->link_res->clock_stop_quirks;
if (clock_stop_quirks & SDW_INTEL_CLK_STOP_TEARDOWN) {
ret = intel_init(sdw);
if (ret) {
dev_err(dev, "%s failed: %d\n", __func__, ret);
return ret;
}
/*
* make sure all Slaves are tagged as UNATTACHED and provide
* reason for reinitialization
*/
sdw_clear_slave_status(bus, SDW_UNATTACH_REQUEST_MASTER_RESET);
ret = sdw_cdns_enable_interrupt(cdns, true);
if (ret < 0) {
dev_err(dev, "cannot enable interrupts during resume\n");
return ret;
}
/*
* follow recommended programming flows to avoid
* timeouts when gsync is enabled
*/
if (multi_link)
intel_shim_sync_arm(sdw);
ret = sdw_cdns_init(&sdw->cdns);
if (ret < 0) {
dev_err(dev, "unable to initialize Cadence IP during resume\n");
return ret;
}
ret = sdw_cdns_exit_reset(cdns);
if (ret < 0) {
dev_err(dev, "unable to exit bus reset sequence during resume\n");
return ret;
}
if (multi_link) {
ret = intel_shim_sync_go(sdw);
if (ret < 0) {
dev_err(dev, "sync go failed during resume\n");
return ret;
}
}
soundwire: cadence: add paranoid check on self-clearing bits The Cadence IP exposes a small number of self-clearing bits in the MCP_CONTROL and MCP_CONFIG_UPDATE registers. We currently do not check that those bits are indeed cleared, e.g. during resume operations. That could lead to resuming peripheral devices too early. In addition, if we happen to read these registers, update one of the fields and write the register back, we may be writing stale data that might have been cleared in hardware. These sort of race conditions could lead to e.g. doing a hw_reset twice or stopping a clock that just restarted. There is no clear way of avoiding these potential race conditions other than making sure that these registers fields are cleared before any read-modify-write sequence. If we detect this sort of errors, we only log them since there is no clear recovery possible. The only way out is likely to restart the IP with a suspend/resume cycle. Note that the checks are performed before updating the registers, as well as after the Intel 'sync go' sequence in multi-link mode. That should cover both the start and end of suspend/resume hardware configurations. The Multi-Master mode gates the configuration updates until the 'sync go' signal is asserted, so we only check on init and after the end of the 'sync go' sequence. The duration of the usleep_range() was defined by the GSYNC frequency used in multi-master mode. With a 4kHz frequency, any configuration change might be deferred by up to 250us. Extending the range to 1000-1500us should guarantee that the configuration change is completed without any significant impact on the overall resume time. Suggested-by: Bard Liao <yung-chuan.liao@linux.intel.com> Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com> Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com> Link: https://lore.kernel.org/r/20210714051349.13064-1-yung-chuan.liao@linux.intel.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
2021-07-14 13:13:49 +08:00
sdw_cdns_check_self_clearing_bits(cdns, "intel_resume_runtime TEARDOWN",
true, INTEL_MASTER_RESET_ITERATIONS);
} else if (clock_stop_quirks & SDW_INTEL_CLK_STOP_BUS_RESET) {
ret = intel_init(sdw);
if (ret) {
dev_err(dev, "%s failed: %d\n", __func__, ret);
return ret;
}
/*
* An exception condition occurs for the CLK_STOP_BUS_RESET
* case if one or more masters remain active. In this condition,
* all the masters are powered on for they are in the same power
* domain. Master can preserve its context for clock stop0, so
* there is no need to clear slave status and reset bus.
*/
clock_stop0 = sdw_cdns_is_clock_stop(&sdw->cdns);
if (!clock_stop0) {
/*
* make sure all Slaves are tagged as UNATTACHED and
* provide reason for reinitialization
*/
status = SDW_UNATTACH_REQUEST_MASTER_RESET;
sdw_clear_slave_status(bus, status);
ret = sdw_cdns_enable_interrupt(cdns, true);
if (ret < 0) {
dev_err(dev, "cannot enable interrupts during resume\n");
return ret;
}
/*
* follow recommended programming flows to avoid
* timeouts when gsync is enabled
*/
if (multi_link)
intel_shim_sync_arm(sdw);
/*
* Re-initialize the IP since it was powered-off
*/
sdw_cdns_init(&sdw->cdns);
} else {
ret = sdw_cdns_enable_interrupt(cdns, true);
if (ret < 0) {
dev_err(dev, "cannot enable interrupts during resume\n");
return ret;
}
}
ret = sdw_cdns_clock_restart(cdns, !clock_stop0);
if (ret < 0) {
dev_err(dev, "unable to restart clock during resume\n");
return ret;
}
if (!clock_stop0) {
ret = sdw_cdns_exit_reset(cdns);
if (ret < 0) {
dev_err(dev, "unable to exit bus reset sequence during resume\n");
return ret;
}
if (multi_link) {
ret = intel_shim_sync_go(sdw);
if (ret < 0) {
dev_err(sdw->cdns.dev, "sync go failed during resume\n");
return ret;
}
}
}
soundwire: cadence: add paranoid check on self-clearing bits The Cadence IP exposes a small number of self-clearing bits in the MCP_CONTROL and MCP_CONFIG_UPDATE registers. We currently do not check that those bits are indeed cleared, e.g. during resume operations. That could lead to resuming peripheral devices too early. In addition, if we happen to read these registers, update one of the fields and write the register back, we may be writing stale data that might have been cleared in hardware. These sort of race conditions could lead to e.g. doing a hw_reset twice or stopping a clock that just restarted. There is no clear way of avoiding these potential race conditions other than making sure that these registers fields are cleared before any read-modify-write sequence. If we detect this sort of errors, we only log them since there is no clear recovery possible. The only way out is likely to restart the IP with a suspend/resume cycle. Note that the checks are performed before updating the registers, as well as after the Intel 'sync go' sequence in multi-link mode. That should cover both the start and end of suspend/resume hardware configurations. The Multi-Master mode gates the configuration updates until the 'sync go' signal is asserted, so we only check on init and after the end of the 'sync go' sequence. The duration of the usleep_range() was defined by the GSYNC frequency used in multi-master mode. With a 4kHz frequency, any configuration change might be deferred by up to 250us. Extending the range to 1000-1500us should guarantee that the configuration change is completed without any significant impact on the overall resume time. Suggested-by: Bard Liao <yung-chuan.liao@linux.intel.com> Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com> Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com> Link: https://lore.kernel.org/r/20210714051349.13064-1-yung-chuan.liao@linux.intel.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
2021-07-14 13:13:49 +08:00
sdw_cdns_check_self_clearing_bits(cdns, "intel_resume_runtime BUS_RESET",
true, INTEL_MASTER_RESET_ITERATIONS);
} else if (!clock_stop_quirks) {
clock_stop0 = sdw_cdns_is_clock_stop(&sdw->cdns);
if (!clock_stop0)
dev_err(dev, "%s invalid configuration, clock was not stopped", __func__);
ret = intel_init(sdw);
if (ret) {
dev_err(dev, "%s failed: %d\n", __func__, ret);
return ret;
}
ret = sdw_cdns_enable_interrupt(cdns, true);
if (ret < 0) {
dev_err(dev, "cannot enable interrupts during resume\n");
return ret;
}
ret = sdw_cdns_clock_restart(cdns, false);
if (ret < 0) {
dev_err(dev, "unable to resume master during resume\n");
return ret;
}
soundwire: cadence: add paranoid check on self-clearing bits The Cadence IP exposes a small number of self-clearing bits in the MCP_CONTROL and MCP_CONFIG_UPDATE registers. We currently do not check that those bits are indeed cleared, e.g. during resume operations. That could lead to resuming peripheral devices too early. In addition, if we happen to read these registers, update one of the fields and write the register back, we may be writing stale data that might have been cleared in hardware. These sort of race conditions could lead to e.g. doing a hw_reset twice or stopping a clock that just restarted. There is no clear way of avoiding these potential race conditions other than making sure that these registers fields are cleared before any read-modify-write sequence. If we detect this sort of errors, we only log them since there is no clear recovery possible. The only way out is likely to restart the IP with a suspend/resume cycle. Note that the checks are performed before updating the registers, as well as after the Intel 'sync go' sequence in multi-link mode. That should cover both the start and end of suspend/resume hardware configurations. The Multi-Master mode gates the configuration updates until the 'sync go' signal is asserted, so we only check on init and after the end of the 'sync go' sequence. The duration of the usleep_range() was defined by the GSYNC frequency used in multi-master mode. With a 4kHz frequency, any configuration change might be deferred by up to 250us. Extending the range to 1000-1500us should guarantee that the configuration change is completed without any significant impact on the overall resume time. Suggested-by: Bard Liao <yung-chuan.liao@linux.intel.com> Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com> Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com> Link: https://lore.kernel.org/r/20210714051349.13064-1-yung-chuan.liao@linux.intel.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
2021-07-14 13:13:49 +08:00
sdw_cdns_check_self_clearing_bits(cdns, "intel_resume_runtime no_quirks",
true, INTEL_MASTER_RESET_ITERATIONS);
} else {
dev_err(dev, "%s clock_stop_quirks %x unsupported\n",
__func__, clock_stop_quirks);
ret = -EINVAL;
}
return ret;
}
static const struct dev_pm_ops intel_pm = {
soundwire: intel: conditionally exit clock stop mode on system suspend Intel stress tests reported issues with the clock stop mode, specifically when trying to do a system suspend while the link is already pm_runtime suspended. In this case, we need to disable the shim wake, but when the PCI parent device is also pm_runtime suspended the SHIM registers are not accessible. Since this is an invalid corner case, this patch suggests a pm_runtime resume of the entire bus to full power (parent+child devices) before the system suspend so that the shim wake can be disabled. Unlike the suspend operation, the .prepare callbacks are propagated from root device to leaf devices. By adding a .prepare callback at the SoundWire link level, we can double-check the pm_runtime status of the device as well as its parent PCI device. When the problematic configuration is detected, the device is pm_runtime resumed - which by construction also resume its parent. An additional loop is added to resume all child devices. In theory we only need to restart the link, but doing so will also cause the physical devices to synchronize and re-initialize, while their Linux devices remain pm_runtime suspended. It's simpler to make sure the codec devices are fully resumed so that we don't have to deal with zombie states. This additional loop could have been avoided by adding a .prepare callback in SoundWire codec drivers. Functionally this would have been equivalent. The rationale for implementing a loop at the link level is only to reduce the amount of code required to deal at the codec level with an Intel corner case - in other words keep codec drivers independent from Intel platform-specific programming sequences. BugLink: https://github.com/thesofproject/linux/issues/2606 Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com> Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com> Link: https://lore.kernel.org/r/20210818024954.16873-4-yung-chuan.liao@linux.intel.com Signed-off-by: Vinod Koul <vkoul@kernel.org>
2021-08-18 10:49:54 +08:00
.prepare = intel_pm_prepare,
SET_SYSTEM_SLEEP_PM_OPS(intel_suspend, intel_resume)
SET_RUNTIME_PM_OPS(intel_suspend_runtime, intel_resume_runtime, NULL)
};
static const struct auxiliary_device_id intel_link_id_table[] = {
{ .name = "soundwire_intel.link" },
{},
};
MODULE_DEVICE_TABLE(auxiliary, intel_link_id_table);
static struct auxiliary_driver sdw_intel_drv = {
.probe = intel_link_probe,
.remove = intel_link_remove,
.driver = {
/* auxiliary_driver_register() sets .name to be the modname */
.pm = &intel_pm,
},
.id_table = intel_link_id_table
};
module_auxiliary_driver(sdw_intel_drv);
MODULE_LICENSE("Dual BSD/GPL");
MODULE_DESCRIPTION("Intel Soundwire Link Driver");