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OpenCloudOS-Kernel/drivers/soc/qcom/qcom-geni-se.c

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// SPDX-License-Identifier: GPL-2.0
// Copyright (c) 2017-2018, The Linux Foundation. All rights reserved.
#include <linux/acpi.h>
#include <linux/clk.h>
#include <linux/slab.h>
#include <linux/dma-mapping.h>
#include <linux/io.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_platform.h>
#include <linux/pinctrl/consumer.h>
#include <linux/platform_device.h>
#include <linux/qcom-geni-se.h>
/**
* DOC: Overview
*
* Generic Interface (GENI) Serial Engine (SE) Wrapper driver is introduced
* to manage GENI firmware based Qualcomm Universal Peripheral (QUP) Wrapper
* controller. QUP Wrapper is designed to support various serial bus protocols
* like UART, SPI, I2C, I3C, etc.
*/
/**
* DOC: Hardware description
*
* GENI based QUP is a highly-flexible and programmable module for supporting
* a wide range of serial interfaces like UART, SPI, I2C, I3C, etc. A single
* QUP module can provide upto 8 serial interfaces, using its internal
* serial engines. The actual configuration is determined by the target
* platform configuration. The protocol supported by each interface is
* determined by the firmware loaded to the serial engine. Each SE consists
* of a DMA Engine and GENI sub modules which enable serial engines to
* support FIFO and DMA modes of operation.
*
*
* +-----------------------------------------+
* |QUP Wrapper |
* | +----------------------------+ |
* --QUP & SE Clocks--> | Serial Engine N | +-IO------>
* | | ... | | Interface
* <---Clock Perf.----+ +----+-----------------------+ | |
* State Interface | | Serial Engine 1 | | |
* | | | | |
* | | | | |
* <--------AHB-------> | | | |
* | | +----+ |
* | | | |
* | | | |
* <------SE IRQ------+ +----------------------------+ |
* | |
* +-----------------------------------------+
*
* Figure 1: GENI based QUP Wrapper
*
* The GENI submodules include primary and secondary sequencers which are
* used to drive TX & RX operations. On serial interfaces that operate using
* master-slave model, primary sequencer drives both TX & RX operations. On
* serial interfaces that operate using peer-to-peer model, primary sequencer
* drives TX operation and secondary sequencer drives RX operation.
*/
/**
* DOC: Software description
*
* GENI SE Wrapper driver is structured into 2 parts:
*
* geni_wrapper represents QUP Wrapper controller. This part of the driver
* manages QUP Wrapper information such as hardware version, clock
* performance table that is common to all the internal serial engines.
*
* geni_se represents serial engine. This part of the driver manages serial
* engine information such as clocks, containing QUP Wrapper, etc. This part
* of driver also supports operations (eg. initialize the concerned serial
* engine, select between FIFO and DMA mode of operation etc.) that are
* common to all the serial engines and are independent of serial interfaces.
*/
#define MAX_CLK_PERF_LEVEL 32
#define NUM_AHB_CLKS 2
/**
* @struct geni_wrapper - Data structure to represent the QUP Wrapper Core
* @dev: Device pointer of the QUP wrapper core
* @base: Base address of this instance of QUP wrapper core
* @ahb_clks: Handle to the primary & secondary AHB clocks
*/
struct geni_wrapper {
struct device *dev;
void __iomem *base;
struct clk_bulk_data ahb_clks[NUM_AHB_CLKS];
};
#define QUP_HW_VER_REG 0x4
/* Common SE registers */
#define GENI_INIT_CFG_REVISION 0x0
#define GENI_S_INIT_CFG_REVISION 0x4
#define GENI_OUTPUT_CTRL 0x24
#define GENI_CGC_CTRL 0x28
#define GENI_CLK_CTRL_RO 0x60
#define GENI_IF_DISABLE_RO 0x64
#define GENI_FW_S_REVISION_RO 0x6c
#define SE_GENI_BYTE_GRAN 0x254
#define SE_GENI_TX_PACKING_CFG0 0x260
#define SE_GENI_TX_PACKING_CFG1 0x264
#define SE_GENI_RX_PACKING_CFG0 0x284
#define SE_GENI_RX_PACKING_CFG1 0x288
#define SE_GENI_M_GP_LENGTH 0x910
#define SE_GENI_S_GP_LENGTH 0x914
#define SE_DMA_TX_PTR_L 0xc30
#define SE_DMA_TX_PTR_H 0xc34
#define SE_DMA_TX_ATTR 0xc38
#define SE_DMA_TX_LEN 0xc3c
#define SE_DMA_TX_IRQ_EN 0xc48
#define SE_DMA_TX_IRQ_EN_SET 0xc4c
#define SE_DMA_TX_IRQ_EN_CLR 0xc50
#define SE_DMA_TX_LEN_IN 0xc54
#define SE_DMA_TX_MAX_BURST 0xc5c
#define SE_DMA_RX_PTR_L 0xd30
#define SE_DMA_RX_PTR_H 0xd34
#define SE_DMA_RX_ATTR 0xd38
#define SE_DMA_RX_LEN 0xd3c
#define SE_DMA_RX_IRQ_EN 0xd48
#define SE_DMA_RX_IRQ_EN_SET 0xd4c
#define SE_DMA_RX_IRQ_EN_CLR 0xd50
#define SE_DMA_RX_LEN_IN 0xd54
#define SE_DMA_RX_MAX_BURST 0xd5c
#define SE_DMA_RX_FLUSH 0xd60
#define SE_GSI_EVENT_EN 0xe18
#define SE_IRQ_EN 0xe1c
#define SE_DMA_GENERAL_CFG 0xe30
/* GENI_OUTPUT_CTRL fields */
#define DEFAULT_IO_OUTPUT_CTRL_MSK GENMASK(6, 0)
/* GENI_CGC_CTRL fields */
#define CFG_AHB_CLK_CGC_ON BIT(0)
#define CFG_AHB_WR_ACLK_CGC_ON BIT(1)
#define DATA_AHB_CLK_CGC_ON BIT(2)
#define SCLK_CGC_ON BIT(3)
#define TX_CLK_CGC_ON BIT(4)
#define RX_CLK_CGC_ON BIT(5)
#define EXT_CLK_CGC_ON BIT(6)
#define PROG_RAM_HCLK_OFF BIT(8)
#define PROG_RAM_SCLK_OFF BIT(9)
#define DEFAULT_CGC_EN GENMASK(6, 0)
/* SE_GSI_EVENT_EN fields */
#define DMA_RX_EVENT_EN BIT(0)
#define DMA_TX_EVENT_EN BIT(1)
#define GENI_M_EVENT_EN BIT(2)
#define GENI_S_EVENT_EN BIT(3)
/* SE_IRQ_EN fields */
#define DMA_RX_IRQ_EN BIT(0)
#define DMA_TX_IRQ_EN BIT(1)
#define GENI_M_IRQ_EN BIT(2)
#define GENI_S_IRQ_EN BIT(3)
/* SE_DMA_GENERAL_CFG */
#define DMA_RX_CLK_CGC_ON BIT(0)
#define DMA_TX_CLK_CGC_ON BIT(1)
#define DMA_AHB_SLV_CFG_ON BIT(2)
#define AHB_SEC_SLV_CLK_CGC_ON BIT(3)
#define DUMMY_RX_NON_BUFFERABLE BIT(4)
#define RX_DMA_ZERO_PADDING_EN BIT(5)
#define RX_DMA_IRQ_DELAY_MSK GENMASK(8, 6)
#define RX_DMA_IRQ_DELAY_SHFT 6
/**
* geni_se_get_qup_hw_version() - Read the QUP wrapper Hardware version
* @se: Pointer to the corresponding serial engine.
*
* Return: Hardware Version of the wrapper.
*/
u32 geni_se_get_qup_hw_version(struct geni_se *se)
{
struct geni_wrapper *wrapper = se->wrapper;
return readl_relaxed(wrapper->base + QUP_HW_VER_REG);
}
EXPORT_SYMBOL(geni_se_get_qup_hw_version);
static void geni_se_io_set_mode(void __iomem *base)
{
u32 val;
val = readl_relaxed(base + SE_IRQ_EN);
val |= GENI_M_IRQ_EN | GENI_S_IRQ_EN;
val |= DMA_TX_IRQ_EN | DMA_RX_IRQ_EN;
writel_relaxed(val, base + SE_IRQ_EN);
val = readl_relaxed(base + SE_GENI_DMA_MODE_EN);
val &= ~GENI_DMA_MODE_EN;
writel_relaxed(val, base + SE_GENI_DMA_MODE_EN);
writel_relaxed(0, base + SE_GSI_EVENT_EN);
}
static void geni_se_io_init(void __iomem *base)
{
u32 val;
val = readl_relaxed(base + GENI_CGC_CTRL);
val |= DEFAULT_CGC_EN;
writel_relaxed(val, base + GENI_CGC_CTRL);
val = readl_relaxed(base + SE_DMA_GENERAL_CFG);
val |= AHB_SEC_SLV_CLK_CGC_ON | DMA_AHB_SLV_CFG_ON;
val |= DMA_TX_CLK_CGC_ON | DMA_RX_CLK_CGC_ON;
writel_relaxed(val, base + SE_DMA_GENERAL_CFG);
writel_relaxed(DEFAULT_IO_OUTPUT_CTRL_MSK, base + GENI_OUTPUT_CTRL);
writel_relaxed(FORCE_DEFAULT, base + GENI_FORCE_DEFAULT_REG);
}
static void geni_se_irq_clear(struct geni_se *se)
{
writel_relaxed(0, se->base + SE_GSI_EVENT_EN);
writel_relaxed(0xffffffff, se->base + SE_GENI_M_IRQ_CLEAR);
writel_relaxed(0xffffffff, se->base + SE_GENI_S_IRQ_CLEAR);
writel_relaxed(0xffffffff, se->base + SE_DMA_TX_IRQ_CLR);
writel_relaxed(0xffffffff, se->base + SE_DMA_RX_IRQ_CLR);
writel_relaxed(0xffffffff, se->base + SE_IRQ_EN);
}
/**
* geni_se_init() - Initialize the GENI serial engine
* @se: Pointer to the concerned serial engine.
* @rx_wm: Receive watermark, in units of FIFO words.
* @rx_rfr_wm: Ready-for-receive watermark, in units of FIFO words.
*
* This function is used to initialize the GENI serial engine, configure
* receive watermark and ready-for-receive watermarks.
*/
void geni_se_init(struct geni_se *se, u32 rx_wm, u32 rx_rfr)
{
u32 val;
geni_se_irq_clear(se);
geni_se_io_init(se->base);
geni_se_io_set_mode(se->base);
writel_relaxed(rx_wm, se->base + SE_GENI_RX_WATERMARK_REG);
writel_relaxed(rx_rfr, se->base + SE_GENI_RX_RFR_WATERMARK_REG);
val = readl_relaxed(se->base + SE_GENI_M_IRQ_EN);
val |= M_COMMON_GENI_M_IRQ_EN;
writel_relaxed(val, se->base + SE_GENI_M_IRQ_EN);
val = readl_relaxed(se->base + SE_GENI_S_IRQ_EN);
val |= S_COMMON_GENI_S_IRQ_EN;
writel_relaxed(val, se->base + SE_GENI_S_IRQ_EN);
}
EXPORT_SYMBOL(geni_se_init);
static void geni_se_select_fifo_mode(struct geni_se *se)
{
u32 proto = geni_se_read_proto(se);
u32 val;
geni_se_irq_clear(se);
val = readl_relaxed(se->base + SE_GENI_M_IRQ_EN);
if (proto != GENI_SE_UART) {
val |= M_CMD_DONE_EN | M_TX_FIFO_WATERMARK_EN;
val |= M_RX_FIFO_WATERMARK_EN | M_RX_FIFO_LAST_EN;
}
writel_relaxed(val, se->base + SE_GENI_M_IRQ_EN);
val = readl_relaxed(se->base + SE_GENI_S_IRQ_EN);
if (proto != GENI_SE_UART)
val |= S_CMD_DONE_EN;
writel_relaxed(val, se->base + SE_GENI_S_IRQ_EN);
val = readl_relaxed(se->base + SE_GENI_DMA_MODE_EN);
val &= ~GENI_DMA_MODE_EN;
writel_relaxed(val, se->base + SE_GENI_DMA_MODE_EN);
}
static void geni_se_select_dma_mode(struct geni_se *se)
{
u32 proto = geni_se_read_proto(se);
u32 val;
geni_se_irq_clear(se);
val = readl_relaxed(se->base + SE_GENI_M_IRQ_EN);
if (proto != GENI_SE_UART) {
val &= ~(M_CMD_DONE_EN | M_TX_FIFO_WATERMARK_EN);
val &= ~(M_RX_FIFO_WATERMARK_EN | M_RX_FIFO_LAST_EN);
}
writel_relaxed(val, se->base + SE_GENI_M_IRQ_EN);
val = readl_relaxed(se->base + SE_GENI_S_IRQ_EN);
if (proto != GENI_SE_UART)
val &= ~S_CMD_DONE_EN;
writel_relaxed(val, se->base + SE_GENI_S_IRQ_EN);
val = readl_relaxed(se->base + SE_GENI_DMA_MODE_EN);
val |= GENI_DMA_MODE_EN;
writel_relaxed(val, se->base + SE_GENI_DMA_MODE_EN);
}
/**
* geni_se_select_mode() - Select the serial engine transfer mode
* @se: Pointer to the concerned serial engine.
* @mode: Transfer mode to be selected.
*/
void geni_se_select_mode(struct geni_se *se, enum geni_se_xfer_mode mode)
{
WARN_ON(mode != GENI_SE_FIFO && mode != GENI_SE_DMA);
switch (mode) {
case GENI_SE_FIFO:
geni_se_select_fifo_mode(se);
break;
case GENI_SE_DMA:
geni_se_select_dma_mode(se);
break;
case GENI_SE_INVALID:
default:
break;
}
}
EXPORT_SYMBOL(geni_se_select_mode);
/**
* DOC: Overview
*
* GENI FIFO packing is highly configurable. TX/RX packing/unpacking consist
* of up to 4 operations, each operation represented by 4 configuration vectors
* of 10 bits programmed in GENI_TX_PACKING_CFG0 and GENI_TX_PACKING_CFG1 for
* TX FIFO and in GENI_RX_PACKING_CFG0 and GENI_RX_PACKING_CFG1 for RX FIFO.
* Refer to below examples for detailed bit-field description.
*
* Example 1: word_size = 7, packing_mode = 4 x 8, msb_to_lsb = 1
*
* +-----------+-------+-------+-------+-------+
* | | vec_0 | vec_1 | vec_2 | vec_3 |
* +-----------+-------+-------+-------+-------+
* | start | 0x6 | 0xe | 0x16 | 0x1e |
* | direction | 1 | 1 | 1 | 1 |
* | length | 6 | 6 | 6 | 6 |
* | stop | 0 | 0 | 0 | 1 |
* +-----------+-------+-------+-------+-------+
*
* Example 2: word_size = 15, packing_mode = 2 x 16, msb_to_lsb = 0
*
* +-----------+-------+-------+-------+-------+
* | | vec_0 | vec_1 | vec_2 | vec_3 |
* +-----------+-------+-------+-------+-------+
* | start | 0x0 | 0x8 | 0x10 | 0x18 |
* | direction | 0 | 0 | 0 | 0 |
* | length | 7 | 6 | 7 | 6 |
* | stop | 0 | 0 | 0 | 1 |
* +-----------+-------+-------+-------+-------+
*
* Example 3: word_size = 23, packing_mode = 1 x 32, msb_to_lsb = 1
*
* +-----------+-------+-------+-------+-------+
* | | vec_0 | vec_1 | vec_2 | vec_3 |
* +-----------+-------+-------+-------+-------+
* | start | 0x16 | 0xe | 0x6 | 0x0 |
* | direction | 1 | 1 | 1 | 1 |
* | length | 7 | 7 | 6 | 0 |
* | stop | 0 | 0 | 1 | 0 |
* +-----------+-------+-------+-------+-------+
*
*/
#define NUM_PACKING_VECTORS 4
#define PACKING_START_SHIFT 5
#define PACKING_DIR_SHIFT 4
#define PACKING_LEN_SHIFT 1
#define PACKING_STOP_BIT BIT(0)
#define PACKING_VECTOR_SHIFT 10
/**
* geni_se_config_packing() - Packing configuration of the serial engine
* @se: Pointer to the concerned serial engine
* @bpw: Bits of data per transfer word.
* @pack_words: Number of words per fifo element.
* @msb_to_lsb: Transfer from MSB to LSB or vice-versa.
* @tx_cfg: Flag to configure the TX Packing.
* @rx_cfg: Flag to configure the RX Packing.
*
* This function is used to configure the packing rules for the current
* transfer.
*/
void geni_se_config_packing(struct geni_se *se, int bpw, int pack_words,
bool msb_to_lsb, bool tx_cfg, bool rx_cfg)
{
u32 cfg0, cfg1, cfg[NUM_PACKING_VECTORS] = {0};
int len;
int temp_bpw = bpw;
int idx_start = msb_to_lsb ? bpw - 1 : 0;
int idx = idx_start;
int idx_delta = msb_to_lsb ? -BITS_PER_BYTE : BITS_PER_BYTE;
int ceil_bpw = ALIGN(bpw, BITS_PER_BYTE);
int iter = (ceil_bpw * pack_words) / BITS_PER_BYTE;
int i;
if (iter <= 0 || iter > NUM_PACKING_VECTORS)
return;
for (i = 0; i < iter; i++) {
len = min_t(int, temp_bpw, BITS_PER_BYTE) - 1;
cfg[i] = idx << PACKING_START_SHIFT;
cfg[i] |= msb_to_lsb << PACKING_DIR_SHIFT;
cfg[i] |= len << PACKING_LEN_SHIFT;
if (temp_bpw <= BITS_PER_BYTE) {
idx = ((i + 1) * BITS_PER_BYTE) + idx_start;
temp_bpw = bpw;
} else {
idx = idx + idx_delta;
temp_bpw = temp_bpw - BITS_PER_BYTE;
}
}
cfg[iter - 1] |= PACKING_STOP_BIT;
cfg0 = cfg[0] | (cfg[1] << PACKING_VECTOR_SHIFT);
cfg1 = cfg[2] | (cfg[3] << PACKING_VECTOR_SHIFT);
if (tx_cfg) {
writel_relaxed(cfg0, se->base + SE_GENI_TX_PACKING_CFG0);
writel_relaxed(cfg1, se->base + SE_GENI_TX_PACKING_CFG1);
}
if (rx_cfg) {
writel_relaxed(cfg0, se->base + SE_GENI_RX_PACKING_CFG0);
writel_relaxed(cfg1, se->base + SE_GENI_RX_PACKING_CFG1);
}
/*
* Number of protocol words in each FIFO entry
* 0 - 4x8, four words in each entry, max word size of 8 bits
* 1 - 2x16, two words in each entry, max word size of 16 bits
* 2 - 1x32, one word in each entry, max word size of 32 bits
* 3 - undefined
*/
if (pack_words || bpw == 32)
writel_relaxed(bpw / 16, se->base + SE_GENI_BYTE_GRAN);
}
EXPORT_SYMBOL(geni_se_config_packing);
static void geni_se_clks_off(struct geni_se *se)
{
struct geni_wrapper *wrapper = se->wrapper;
clk_disable_unprepare(se->clk);
clk_bulk_disable_unprepare(ARRAY_SIZE(wrapper->ahb_clks),
wrapper->ahb_clks);
}
/**
* geni_se_resources_off() - Turn off resources associated with the serial
* engine
* @se: Pointer to the concerned serial engine.
*
* Return: 0 on success, standard Linux error codes on failure/error.
*/
int geni_se_resources_off(struct geni_se *se)
{
int ret;
if (has_acpi_companion(se->dev))
return 0;
ret = pinctrl_pm_select_sleep_state(se->dev);
if (ret)
return ret;
geni_se_clks_off(se);
return 0;
}
EXPORT_SYMBOL(geni_se_resources_off);
static int geni_se_clks_on(struct geni_se *se)
{
int ret;
struct geni_wrapper *wrapper = se->wrapper;
ret = clk_bulk_prepare_enable(ARRAY_SIZE(wrapper->ahb_clks),
wrapper->ahb_clks);
if (ret)
return ret;
ret = clk_prepare_enable(se->clk);
if (ret)
clk_bulk_disable_unprepare(ARRAY_SIZE(wrapper->ahb_clks),
wrapper->ahb_clks);
return ret;
}
/**
* geni_se_resources_on() - Turn on resources associated with the serial
* engine
* @se: Pointer to the concerned serial engine.
*
* Return: 0 on success, standard Linux error codes on failure/error.
*/
int geni_se_resources_on(struct geni_se *se)
{
int ret;
if (has_acpi_companion(se->dev))
return 0;
ret = geni_se_clks_on(se);
if (ret)
return ret;
ret = pinctrl_pm_select_default_state(se->dev);
if (ret)
geni_se_clks_off(se);
return ret;
}
EXPORT_SYMBOL(geni_se_resources_on);
/**
* geni_se_clk_tbl_get() - Get the clock table to program DFS
* @se: Pointer to the concerned serial engine.
* @tbl: Table in which the output is returned.
*
* This function is called by the protocol drivers to determine the different
* clock frequencies supported by serial engine core clock. The protocol
* drivers use the output to determine the clock frequency index to be
* programmed into DFS.
*
* Return: number of valid performance levels in the table on success,
* standard Linux error codes on failure.
*/
int geni_se_clk_tbl_get(struct geni_se *se, unsigned long **tbl)
{
long freq = 0;
int i;
if (se->clk_perf_tbl) {
*tbl = se->clk_perf_tbl;
return se->num_clk_levels;
}
se->clk_perf_tbl = devm_kcalloc(se->dev, MAX_CLK_PERF_LEVEL,
sizeof(*se->clk_perf_tbl),
GFP_KERNEL);
if (!se->clk_perf_tbl)
return -ENOMEM;
for (i = 0; i < MAX_CLK_PERF_LEVEL; i++) {
freq = clk_round_rate(se->clk, freq + 1);
if (freq <= 0 || freq == se->clk_perf_tbl[i - 1])
break;
se->clk_perf_tbl[i] = freq;
}
se->num_clk_levels = i;
*tbl = se->clk_perf_tbl;
return se->num_clk_levels;
}
EXPORT_SYMBOL(geni_se_clk_tbl_get);
/**
* geni_se_clk_freq_match() - Get the matching or closest SE clock frequency
* @se: Pointer to the concerned serial engine.
* @req_freq: Requested clock frequency.
* @index: Index of the resultant frequency in the table.
* @res_freq: Resultant frequency of the source clock.
* @exact: Flag to indicate exact multiple requirement of the requested
* frequency.
*
* This function is called by the protocol drivers to determine the best match
* of the requested frequency as provided by the serial engine clock in order
* to meet the performance requirements.
*
* If we return success:
* - if @exact is true then @res_freq / <an_integer> == @req_freq
* - if @exact is false then @res_freq / <an_integer> <= @req_freq
*
* Return: 0 on success, standard Linux error codes on failure.
*/
int geni_se_clk_freq_match(struct geni_se *se, unsigned long req_freq,
unsigned int *index, unsigned long *res_freq,
bool exact)
{
unsigned long *tbl;
int num_clk_levels;
int i;
unsigned long best_delta;
unsigned long new_delta;
unsigned int divider;
num_clk_levels = geni_se_clk_tbl_get(se, &tbl);
if (num_clk_levels < 0)
return num_clk_levels;
if (num_clk_levels == 0)
return -EINVAL;
best_delta = ULONG_MAX;
for (i = 0; i < num_clk_levels; i++) {
divider = DIV_ROUND_UP(tbl[i], req_freq);
new_delta = req_freq - tbl[i] / divider;
if (new_delta < best_delta) {
/* We have a new best! */
*index = i;
*res_freq = tbl[i];
/* If the new best is exact then we're done */
if (new_delta == 0)
return 0;
/* Record how close we got */
best_delta = new_delta;
}
}
if (exact)
return -EINVAL;
return 0;
}
EXPORT_SYMBOL(geni_se_clk_freq_match);
#define GENI_SE_DMA_DONE_EN BIT(0)
#define GENI_SE_DMA_EOT_EN BIT(1)
#define GENI_SE_DMA_AHB_ERR_EN BIT(2)
#define GENI_SE_DMA_EOT_BUF BIT(0)
/**
* geni_se_tx_dma_prep() - Prepare the serial engine for TX DMA transfer
* @se: Pointer to the concerned serial engine.
* @buf: Pointer to the TX buffer.
* @len: Length of the TX buffer.
* @iova: Pointer to store the mapped DMA address.
*
* This function is used to prepare the buffers for DMA TX.
*
* Return: 0 on success, standard Linux error codes on failure.
*/
int geni_se_tx_dma_prep(struct geni_se *se, void *buf, size_t len,
dma_addr_t *iova)
{
struct geni_wrapper *wrapper = se->wrapper;
u32 val;
if (!wrapper)
return -EINVAL;
*iova = dma_map_single(wrapper->dev, buf, len, DMA_TO_DEVICE);
if (dma_mapping_error(wrapper->dev, *iova))
return -EIO;
val = GENI_SE_DMA_DONE_EN;
val |= GENI_SE_DMA_EOT_EN;
val |= GENI_SE_DMA_AHB_ERR_EN;
writel_relaxed(val, se->base + SE_DMA_TX_IRQ_EN_SET);
writel_relaxed(lower_32_bits(*iova), se->base + SE_DMA_TX_PTR_L);
writel_relaxed(upper_32_bits(*iova), se->base + SE_DMA_TX_PTR_H);
writel_relaxed(GENI_SE_DMA_EOT_BUF, se->base + SE_DMA_TX_ATTR);
writel(len, se->base + SE_DMA_TX_LEN);
return 0;
}
EXPORT_SYMBOL(geni_se_tx_dma_prep);
/**
* geni_se_rx_dma_prep() - Prepare the serial engine for RX DMA transfer
* @se: Pointer to the concerned serial engine.
* @buf: Pointer to the RX buffer.
* @len: Length of the RX buffer.
* @iova: Pointer to store the mapped DMA address.
*
* This function is used to prepare the buffers for DMA RX.
*
* Return: 0 on success, standard Linux error codes on failure.
*/
int geni_se_rx_dma_prep(struct geni_se *se, void *buf, size_t len,
dma_addr_t *iova)
{
struct geni_wrapper *wrapper = se->wrapper;
u32 val;
if (!wrapper)
return -EINVAL;
*iova = dma_map_single(wrapper->dev, buf, len, DMA_FROM_DEVICE);
if (dma_mapping_error(wrapper->dev, *iova))
return -EIO;
val = GENI_SE_DMA_DONE_EN;
val |= GENI_SE_DMA_EOT_EN;
val |= GENI_SE_DMA_AHB_ERR_EN;
writel_relaxed(val, se->base + SE_DMA_RX_IRQ_EN_SET);
writel_relaxed(lower_32_bits(*iova), se->base + SE_DMA_RX_PTR_L);
writel_relaxed(upper_32_bits(*iova), se->base + SE_DMA_RX_PTR_H);
/* RX does not have EOT buffer type bit. So just reset RX_ATTR */
writel_relaxed(0, se->base + SE_DMA_RX_ATTR);
writel(len, se->base + SE_DMA_RX_LEN);
return 0;
}
EXPORT_SYMBOL(geni_se_rx_dma_prep);
/**
* geni_se_tx_dma_unprep() - Unprepare the serial engine after TX DMA transfer
* @se: Pointer to the concerned serial engine.
* @iova: DMA address of the TX buffer.
* @len: Length of the TX buffer.
*
* This function is used to unprepare the DMA buffers after DMA TX.
*/
void geni_se_tx_dma_unprep(struct geni_se *se, dma_addr_t iova, size_t len)
{
struct geni_wrapper *wrapper = se->wrapper;
if (iova && !dma_mapping_error(wrapper->dev, iova))
dma_unmap_single(wrapper->dev, iova, len, DMA_TO_DEVICE);
}
EXPORT_SYMBOL(geni_se_tx_dma_unprep);
/**
* geni_se_rx_dma_unprep() - Unprepare the serial engine after RX DMA transfer
* @se: Pointer to the concerned serial engine.
* @iova: DMA address of the RX buffer.
* @len: Length of the RX buffer.
*
* This function is used to unprepare the DMA buffers after DMA RX.
*/
void geni_se_rx_dma_unprep(struct geni_se *se, dma_addr_t iova, size_t len)
{
struct geni_wrapper *wrapper = se->wrapper;
if (iova && !dma_mapping_error(wrapper->dev, iova))
dma_unmap_single(wrapper->dev, iova, len, DMA_FROM_DEVICE);
}
EXPORT_SYMBOL(geni_se_rx_dma_unprep);
static int geni_se_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct resource *res;
struct geni_wrapper *wrapper;
int ret;
wrapper = devm_kzalloc(dev, sizeof(*wrapper), GFP_KERNEL);
if (!wrapper)
return -ENOMEM;
wrapper->dev = dev;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
wrapper->base = devm_ioremap_resource(dev, res);
if (IS_ERR(wrapper->base))
return PTR_ERR(wrapper->base);
if (!has_acpi_companion(&pdev->dev)) {
wrapper->ahb_clks[0].id = "m-ahb";
wrapper->ahb_clks[1].id = "s-ahb";
ret = devm_clk_bulk_get(dev, NUM_AHB_CLKS, wrapper->ahb_clks);
if (ret) {
dev_err(dev, "Err getting AHB clks %d\n", ret);
return ret;
}
}
dev_set_drvdata(dev, wrapper);
dev_dbg(dev, "GENI SE Driver probed\n");
return devm_of_platform_populate(dev);
}
static const struct of_device_id geni_se_dt_match[] = {
{ .compatible = "qcom,geni-se-qup", },
{}
};
MODULE_DEVICE_TABLE(of, geni_se_dt_match);
static struct platform_driver geni_se_driver = {
.driver = {
.name = "geni_se_qup",
.of_match_table = geni_se_dt_match,
},
.probe = geni_se_probe,
};
module_platform_driver(geni_se_driver);
MODULE_DESCRIPTION("GENI Serial Engine Driver");
MODULE_LICENSE("GPL v2");
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