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OpenCloudOS-Kernel/drivers/mmc/host/sdhci-pci-o2micro.c

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// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (C) 2013 BayHub Technology Ltd.
*
* Authors: Peter Guo <peter.guo@bayhubtech.com>
* Adam Lee <adam.lee@canonical.com>
* Ernest Zhang <ernest.zhang@bayhubtech.com>
*/
#include <linux/pci.h>
#include <linux/mmc/host.h>
#include <linux/mmc/mmc.h>
#include <linux/delay.h>
#include "sdhci.h"
#include "sdhci-pci.h"
/*
* O2Micro device registers
*/
#define O2_SD_MISC_REG5 0x64
#define O2_SD_LD0_CTRL 0x68
#define O2_SD_DEV_CTRL 0x88
#define O2_SD_LOCK_WP 0xD3
#define O2_SD_TEST_REG 0xD4
#define O2_SD_FUNC_REG0 0xDC
#define O2_SD_MULTI_VCC3V 0xEE
#define O2_SD_CLKREQ 0xEC
#define O2_SD_CAPS 0xE0
#define O2_SD_ADMA1 0xE2
#define O2_SD_ADMA2 0xE7
#define O2_SD_INF_MOD 0xF1
#define O2_SD_MISC_CTRL4 0xFC
#define O2_SD_TUNING_CTRL 0x300
#define O2_SD_PLL_SETTING 0x304
#define O2_SD_MISC_SETTING 0x308
#define O2_SD_CLK_SETTING 0x328
#define O2_SD_CAP_REG2 0x330
#define O2_SD_CAP_REG0 0x334
#define O2_SD_UHS1_CAP_SETTING 0x33C
#define O2_SD_DELAY_CTRL 0x350
#define O2_SD_UHS2_L1_CTRL 0x35C
#define O2_SD_FUNC_REG3 0x3E0
#define O2_SD_FUNC_REG4 0x3E4
#define O2_SD_LED_ENABLE BIT(6)
#define O2_SD_FREG0_LEDOFF BIT(13)
#define O2_SD_FREG4_ENABLE_CLK_SET BIT(22)
#define O2_SD_VENDOR_SETTING 0x110
#define O2_SD_VENDOR_SETTING2 0x1C8
#define O2_SD_HW_TUNING_DISABLE BIT(4)
#define O2_PLL_WDT_CONTROL1 0x1CC
#define O2_PLL_FORCE_ACTIVE BIT(18)
#define O2_PLL_LOCK_STATUS BIT(14)
#define O2_PLL_SOFT_RESET BIT(12)
#define O2_SD_DETECT_SETTING 0x324
static void sdhci_o2_set_tuning_mode(struct sdhci_host *host)
{
u16 reg;
/* enable hardware tuning */
reg = sdhci_readw(host, O2_SD_VENDOR_SETTING);
reg &= ~O2_SD_HW_TUNING_DISABLE;
sdhci_writew(host, reg, O2_SD_VENDOR_SETTING);
}
static void __sdhci_o2_execute_tuning(struct sdhci_host *host, u32 opcode)
{
int i;
sdhci_send_tuning(host, MMC_SEND_TUNING_BLOCK_HS200);
for (i = 0; i < 150; i++) {
u16 ctrl = sdhci_readw(host, SDHCI_HOST_CONTROL2);
if (!(ctrl & SDHCI_CTRL_EXEC_TUNING)) {
if (ctrl & SDHCI_CTRL_TUNED_CLK) {
host->tuning_done = true;
return;
}
pr_warn("%s: HW tuning failed !\n",
mmc_hostname(host->mmc));
break;
}
mdelay(1);
}
pr_info("%s: Tuning failed, falling back to fixed sampling clock\n",
mmc_hostname(host->mmc));
sdhci_reset_tuning(host);
}
static int sdhci_o2_execute_tuning(struct mmc_host *mmc, u32 opcode)
{
struct sdhci_host *host = mmc_priv(mmc);
int current_bus_width = 0;
/*
* This handler only implements the eMMC tuning that is specific to
* this controller. Fall back to the standard method for other TIMING.
*/
if (host->timing != MMC_TIMING_MMC_HS200)
return sdhci_execute_tuning(mmc, opcode);
if (WARN_ON(opcode != MMC_SEND_TUNING_BLOCK_HS200))
return -EINVAL;
/*
* o2 sdhci host didn't support 8bit emmc tuning
*/
if (mmc->ios.bus_width == MMC_BUS_WIDTH_8) {
current_bus_width = mmc->ios.bus_width;
mmc->ios.bus_width = MMC_BUS_WIDTH_4;
sdhci_set_bus_width(host, MMC_BUS_WIDTH_4);
}
sdhci_o2_set_tuning_mode(host);
sdhci_start_tuning(host);
__sdhci_o2_execute_tuning(host, opcode);
sdhci_end_tuning(host);
if (current_bus_width == MMC_BUS_WIDTH_8) {
mmc->ios.bus_width = MMC_BUS_WIDTH_8;
sdhci_set_bus_width(host, current_bus_width);
}
host->flags &= ~SDHCI_HS400_TUNING;
return 0;
}
static void o2_pci_set_baseclk(struct sdhci_pci_chip *chip, u32 value)
{
u32 scratch_32;
pci_read_config_dword(chip->pdev,
O2_SD_PLL_SETTING, &scratch_32);
scratch_32 &= 0x0000FFFF;
scratch_32 |= value;
pci_write_config_dword(chip->pdev,
O2_SD_PLL_SETTING, scratch_32);
}
static void o2_pci_led_enable(struct sdhci_pci_chip *chip)
{
int ret;
u32 scratch_32;
/* Set led of SD host function enable */
ret = pci_read_config_dword(chip->pdev,
O2_SD_FUNC_REG0, &scratch_32);
if (ret)
return;
scratch_32 &= ~O2_SD_FREG0_LEDOFF;
pci_write_config_dword(chip->pdev,
O2_SD_FUNC_REG0, scratch_32);
ret = pci_read_config_dword(chip->pdev,
O2_SD_TEST_REG, &scratch_32);
if (ret)
return;
scratch_32 |= O2_SD_LED_ENABLE;
pci_write_config_dword(chip->pdev,
O2_SD_TEST_REG, scratch_32);
}
static void sdhci_pci_o2_fujin2_pci_init(struct sdhci_pci_chip *chip)
{
u32 scratch_32;
int ret;
/* Improve write performance for SD3.0 */
ret = pci_read_config_dword(chip->pdev, O2_SD_DEV_CTRL, &scratch_32);
if (ret)
return;
scratch_32 &= ~((1 << 12) | (1 << 13) | (1 << 14));
pci_write_config_dword(chip->pdev, O2_SD_DEV_CTRL, scratch_32);
/* Enable Link abnormal reset generating Reset */
ret = pci_read_config_dword(chip->pdev, O2_SD_MISC_REG5, &scratch_32);
if (ret)
return;
scratch_32 &= ~((1 << 19) | (1 << 11));
scratch_32 |= (1 << 10);
pci_write_config_dword(chip->pdev, O2_SD_MISC_REG5, scratch_32);
/* set card power over current protection */
ret = pci_read_config_dword(chip->pdev, O2_SD_TEST_REG, &scratch_32);
if (ret)
return;
scratch_32 |= (1 << 4);
pci_write_config_dword(chip->pdev, O2_SD_TEST_REG, scratch_32);
/* adjust the output delay for SD mode */
pci_write_config_dword(chip->pdev, O2_SD_DELAY_CTRL, 0x00002492);
/* Set the output voltage setting of Aux 1.2v LDO */
ret = pci_read_config_dword(chip->pdev, O2_SD_LD0_CTRL, &scratch_32);
if (ret)
return;
scratch_32 &= ~(3 << 12);
pci_write_config_dword(chip->pdev, O2_SD_LD0_CTRL, scratch_32);
/* Set Max power supply capability of SD host */
ret = pci_read_config_dword(chip->pdev, O2_SD_CAP_REG0, &scratch_32);
if (ret)
return;
scratch_32 &= ~(0x01FE);
scratch_32 |= 0x00CC;
pci_write_config_dword(chip->pdev, O2_SD_CAP_REG0, scratch_32);
/* Set DLL Tuning Window */
ret = pci_read_config_dword(chip->pdev,
O2_SD_TUNING_CTRL, &scratch_32);
if (ret)
return;
scratch_32 &= ~(0x000000FF);
scratch_32 |= 0x00000066;
pci_write_config_dword(chip->pdev, O2_SD_TUNING_CTRL, scratch_32);
/* Set UHS2 T_EIDLE */
ret = pci_read_config_dword(chip->pdev,
O2_SD_UHS2_L1_CTRL, &scratch_32);
if (ret)
return;
scratch_32 &= ~(0x000000FC);
scratch_32 |= 0x00000084;
pci_write_config_dword(chip->pdev, O2_SD_UHS2_L1_CTRL, scratch_32);
/* Set UHS2 Termination */
ret = pci_read_config_dword(chip->pdev, O2_SD_FUNC_REG3, &scratch_32);
if (ret)
return;
scratch_32 &= ~((1 << 21) | (1 << 30));
pci_write_config_dword(chip->pdev, O2_SD_FUNC_REG3, scratch_32);
/* Set L1 Entrance Timer */
ret = pci_read_config_dword(chip->pdev, O2_SD_CAPS, &scratch_32);
if (ret)
return;
scratch_32 &= ~(0xf0000000);
scratch_32 |= 0x30000000;
pci_write_config_dword(chip->pdev, O2_SD_CAPS, scratch_32);
ret = pci_read_config_dword(chip->pdev,
O2_SD_MISC_CTRL4, &scratch_32);
if (ret)
return;
scratch_32 &= ~(0x000f0000);
scratch_32 |= 0x00080000;
pci_write_config_dword(chip->pdev, O2_SD_MISC_CTRL4, scratch_32);
}
static void sdhci_pci_o2_enable_msi(struct sdhci_pci_chip *chip,
struct sdhci_host *host)
{
int ret;
ret = pci_find_capability(chip->pdev, PCI_CAP_ID_MSI);
if (!ret) {
pr_info("%s: unsupport msi, use INTx irq\n",
mmc_hostname(host->mmc));
return;
}
ret = pci_alloc_irq_vectors(chip->pdev, 1, 1,
PCI_IRQ_MSI | PCI_IRQ_MSIX);
if (ret < 0) {
pr_err("%s: enable PCI MSI failed, err=%d\n",
mmc_hostname(host->mmc), ret);
return;
}
host->irq = pci_irq_vector(chip->pdev, 0);
}
static void sdhci_o2_wait_card_detect_stable(struct sdhci_host *host)
{
ktime_t timeout;
u32 scratch32;
/* Wait max 50 ms */
timeout = ktime_add_ms(ktime_get(), 50);
while (1) {
bool timedout = ktime_after(ktime_get(), timeout);
scratch32 = sdhci_readl(host, SDHCI_PRESENT_STATE);
if ((scratch32 & SDHCI_CARD_PRESENT) >> SDHCI_CARD_PRES_SHIFT
== (scratch32 & SDHCI_CD_LVL) >> SDHCI_CD_LVL_SHIFT)
break;
if (timedout) {
pr_err("%s: Card Detect debounce never finished.\n",
mmc_hostname(host->mmc));
sdhci_dumpregs(host);
return;
}
udelay(10);
}
}
static void sdhci_o2_enable_internal_clock(struct sdhci_host *host)
{
ktime_t timeout;
u16 scratch;
u32 scratch32;
/* PLL software reset */
scratch32 = sdhci_readl(host, O2_PLL_WDT_CONTROL1);
scratch32 |= O2_PLL_SOFT_RESET;
sdhci_writel(host, scratch32, O2_PLL_WDT_CONTROL1);
udelay(1);
scratch32 &= ~(O2_PLL_SOFT_RESET);
sdhci_writel(host, scratch32, O2_PLL_WDT_CONTROL1);
/* PLL force active */
scratch32 |= O2_PLL_FORCE_ACTIVE;
sdhci_writel(host, scratch32, O2_PLL_WDT_CONTROL1);
/* Wait max 20 ms */
timeout = ktime_add_ms(ktime_get(), 20);
while (1) {
bool timedout = ktime_after(ktime_get(), timeout);
scratch = sdhci_readw(host, O2_PLL_WDT_CONTROL1);
if (scratch & O2_PLL_LOCK_STATUS)
break;
if (timedout) {
pr_err("%s: Internal clock never stabilised.\n",
mmc_hostname(host->mmc));
sdhci_dumpregs(host);
goto out;
}
udelay(10);
}
/* Wait for card detect finish */
udelay(1);
sdhci_o2_wait_card_detect_stable(host);
out:
/* Cancel PLL force active */
scratch32 = sdhci_readl(host, O2_PLL_WDT_CONTROL1);
scratch32 &= ~O2_PLL_FORCE_ACTIVE;
sdhci_writel(host, scratch32, O2_PLL_WDT_CONTROL1);
}
static int sdhci_o2_get_cd(struct mmc_host *mmc)
{
struct sdhci_host *host = mmc_priv(mmc);
sdhci_o2_enable_internal_clock(host);
return !!(sdhci_readl(host, SDHCI_PRESENT_STATE) & SDHCI_CARD_PRESENT);
}
static void sdhci_o2_enable_clk(struct sdhci_host *host, u16 clk)
{
/* Enable internal clock */
clk |= SDHCI_CLOCK_INT_EN;
sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);
if (sdhci_o2_get_cd(host->mmc)) {
clk |= SDHCI_CLOCK_CARD_EN;
sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);
}
}
void sdhci_pci_o2_set_clock(struct sdhci_host *host, unsigned int clock)
{
u16 clk;
host->mmc->actual_clock = 0;
sdhci_writew(host, 0, SDHCI_CLOCK_CONTROL);
if (clock == 0)
return;
clk = sdhci_calc_clk(host, clock, &host->mmc->actual_clock);
sdhci_o2_enable_clk(host, clk);
}
int sdhci_pci_o2_probe_slot(struct sdhci_pci_slot *slot)
{
struct sdhci_pci_chip *chip;
struct sdhci_host *host;
u32 reg, caps;
int ret;
chip = slot->chip;
host = slot->host;
caps = sdhci_readl(host, SDHCI_CAPABILITIES);
/*
* mmc_select_bus_width() will test the bus to determine the actual bus
* width.
*/
if (caps & SDHCI_CAN_DO_8BIT)
host->mmc->caps |= MMC_CAP_8_BIT_DATA;
switch (chip->pdev->device) {
case PCI_DEVICE_ID_O2_SDS0:
case PCI_DEVICE_ID_O2_SEABIRD0:
case PCI_DEVICE_ID_O2_SEABIRD1:
case PCI_DEVICE_ID_O2_SDS1:
case PCI_DEVICE_ID_O2_FUJIN2:
reg = sdhci_readl(host, O2_SD_VENDOR_SETTING);
if (reg & 0x1)
host->quirks |= SDHCI_QUIRK_MULTIBLOCK_READ_ACMD12;
sdhci_pci_o2_enable_msi(chip, host);
if (chip->pdev->device == PCI_DEVICE_ID_O2_SEABIRD0) {
ret = pci_read_config_dword(chip->pdev,
O2_SD_MISC_SETTING, &reg);
if (ret)
return -EIO;
if (reg & (1 << 4)) {
pr_info("%s: emmc 1.8v flag is set, force 1.8v signaling voltage\n",
mmc_hostname(host->mmc));
host->flags &= ~SDHCI_SIGNALING_330;
host->flags |= SDHCI_SIGNALING_180;
host->quirks2 |= SDHCI_QUIRK2_CLEAR_TRANSFERMODE_REG_BEFORE_CMD;
host->mmc->caps2 |= MMC_CAP2_NO_SD;
host->mmc->caps2 |= MMC_CAP2_NO_SDIO;
pci_write_config_dword(chip->pdev,
O2_SD_DETECT_SETTING, 3);
}
slot->host->mmc_host_ops.get_cd = sdhci_o2_get_cd;
}
host->mmc_host_ops.execute_tuning = sdhci_o2_execute_tuning;
if (chip->pdev->device != PCI_DEVICE_ID_O2_FUJIN2)
break;
/* set dll watch dog timer */
reg = sdhci_readl(host, O2_SD_VENDOR_SETTING2);
reg |= (1 << 12);
sdhci_writel(host, reg, O2_SD_VENDOR_SETTING2);
break;
default:
break;
}
return 0;
}
int sdhci_pci_o2_probe(struct sdhci_pci_chip *chip)
{
int ret;
u8 scratch;
u32 scratch_32;
switch (chip->pdev->device) {
case PCI_DEVICE_ID_O2_8220:
case PCI_DEVICE_ID_O2_8221:
case PCI_DEVICE_ID_O2_8320:
case PCI_DEVICE_ID_O2_8321:
/* This extra setup is required due to broken ADMA. */
ret = pci_read_config_byte(chip->pdev,
O2_SD_LOCK_WP, &scratch);
if (ret)
return ret;
scratch &= 0x7f;
pci_write_config_byte(chip->pdev, O2_SD_LOCK_WP, scratch);
/* Set Multi 3 to VCC3V# */
pci_write_config_byte(chip->pdev, O2_SD_MULTI_VCC3V, 0x08);
/* Disable CLK_REQ# support after media DET */
ret = pci_read_config_byte(chip->pdev,
O2_SD_CLKREQ, &scratch);
if (ret)
return ret;
scratch |= 0x20;
pci_write_config_byte(chip->pdev, O2_SD_CLKREQ, scratch);
/* Choose capabilities, enable SDMA. We have to write 0x01
* to the capabilities register first to unlock it.
*/
ret = pci_read_config_byte(chip->pdev, O2_SD_CAPS, &scratch);
if (ret)
return ret;
scratch |= 0x01;
pci_write_config_byte(chip->pdev, O2_SD_CAPS, scratch);
pci_write_config_byte(chip->pdev, O2_SD_CAPS, 0x73);
/* Disable ADMA1/2 */
pci_write_config_byte(chip->pdev, O2_SD_ADMA1, 0x39);
pci_write_config_byte(chip->pdev, O2_SD_ADMA2, 0x08);
/* Disable the infinite transfer mode */
ret = pci_read_config_byte(chip->pdev,
O2_SD_INF_MOD, &scratch);
if (ret)
return ret;
scratch |= 0x08;
pci_write_config_byte(chip->pdev, O2_SD_INF_MOD, scratch);
/* Lock WP */
ret = pci_read_config_byte(chip->pdev,
O2_SD_LOCK_WP, &scratch);
if (ret)
return ret;
scratch |= 0x80;
pci_write_config_byte(chip->pdev, O2_SD_LOCK_WP, scratch);
break;
case PCI_DEVICE_ID_O2_SDS0:
case PCI_DEVICE_ID_O2_SDS1:
case PCI_DEVICE_ID_O2_FUJIN2:
/* UnLock WP */
ret = pci_read_config_byte(chip->pdev,
O2_SD_LOCK_WP, &scratch);
if (ret)
return ret;
scratch &= 0x7f;
pci_write_config_byte(chip->pdev, O2_SD_LOCK_WP, scratch);
/* DevId=8520 subId= 0x11 or 0x12 Type Chip support */
if (chip->pdev->device == PCI_DEVICE_ID_O2_FUJIN2) {
ret = pci_read_config_dword(chip->pdev,
O2_SD_FUNC_REG0,
&scratch_32);
scratch_32 = ((scratch_32 & 0xFF000000) >> 24);
/* Check Whether subId is 0x11 or 0x12 */
if ((scratch_32 == 0x11) || (scratch_32 == 0x12)) {
scratch_32 = 0x25100000;
o2_pci_set_baseclk(chip, scratch_32);
ret = pci_read_config_dword(chip->pdev,
O2_SD_FUNC_REG4,
&scratch_32);
/* Enable Base Clk setting change */
scratch_32 |= O2_SD_FREG4_ENABLE_CLK_SET;
pci_write_config_dword(chip->pdev,
O2_SD_FUNC_REG4,
scratch_32);
/* Set Tuning Window to 4 */
pci_write_config_byte(chip->pdev,
O2_SD_TUNING_CTRL, 0x44);
break;
}
}
/* Enable 8520 led function */
o2_pci_led_enable(chip);
/* Set timeout CLK */
ret = pci_read_config_dword(chip->pdev,
O2_SD_CLK_SETTING, &scratch_32);
if (ret)
return ret;
scratch_32 &= ~(0xFF00);
scratch_32 |= 0x07E0C800;
pci_write_config_dword(chip->pdev,
O2_SD_CLK_SETTING, scratch_32);
ret = pci_read_config_dword(chip->pdev,
O2_SD_CLKREQ, &scratch_32);
if (ret)
return ret;
scratch_32 |= 0x3;
pci_write_config_dword(chip->pdev, O2_SD_CLKREQ, scratch_32);
ret = pci_read_config_dword(chip->pdev,
O2_SD_PLL_SETTING, &scratch_32);
if (ret)
return ret;
scratch_32 &= ~(0x1F3F070E);
scratch_32 |= 0x18270106;
pci_write_config_dword(chip->pdev,
O2_SD_PLL_SETTING, scratch_32);
/* Disable UHS1 funciton */
ret = pci_read_config_dword(chip->pdev,
O2_SD_CAP_REG2, &scratch_32);
if (ret)
return ret;
scratch_32 &= ~(0xE0);
pci_write_config_dword(chip->pdev,
O2_SD_CAP_REG2, scratch_32);
if (chip->pdev->device == PCI_DEVICE_ID_O2_FUJIN2)
sdhci_pci_o2_fujin2_pci_init(chip);
/* Lock WP */
ret = pci_read_config_byte(chip->pdev,
O2_SD_LOCK_WP, &scratch);
if (ret)
return ret;
scratch |= 0x80;
pci_write_config_byte(chip->pdev, O2_SD_LOCK_WP, scratch);
break;
case PCI_DEVICE_ID_O2_SEABIRD0:
case PCI_DEVICE_ID_O2_SEABIRD1:
/* UnLock WP */
ret = pci_read_config_byte(chip->pdev,
O2_SD_LOCK_WP, &scratch);
if (ret)
return ret;
scratch &= 0x7f;
pci_write_config_byte(chip->pdev, O2_SD_LOCK_WP, scratch);
ret = pci_read_config_dword(chip->pdev,
O2_SD_PLL_SETTING, &scratch_32);
if ((scratch_32 & 0xff000000) == 0x01000000) {
scratch_32 &= 0x0000FFFF;
scratch_32 |= 0x1F340000;
pci_write_config_dword(chip->pdev,
O2_SD_PLL_SETTING, scratch_32);
} else {
scratch_32 &= 0x0000FFFF;
scratch_32 |= 0x25100000;
pci_write_config_dword(chip->pdev,
O2_SD_PLL_SETTING, scratch_32);
ret = pci_read_config_dword(chip->pdev,
O2_SD_FUNC_REG4,
&scratch_32);
scratch_32 |= (1 << 22);
pci_write_config_dword(chip->pdev,
O2_SD_FUNC_REG4, scratch_32);
}
/* Set Tuning Windows to 5 */
pci_write_config_byte(chip->pdev,
O2_SD_TUNING_CTRL, 0x55);
/* Lock WP */
ret = pci_read_config_byte(chip->pdev,
O2_SD_LOCK_WP, &scratch);
if (ret)
return ret;
scratch |= 0x80;
pci_write_config_byte(chip->pdev, O2_SD_LOCK_WP, scratch);
break;
}
return 0;
}
#ifdef CONFIG_PM_SLEEP
int sdhci_pci_o2_resume(struct sdhci_pci_chip *chip)
{
sdhci_pci_o2_probe(chip);
return sdhci_pci_resume_host(chip);
}
#endif
static const struct sdhci_ops sdhci_pci_o2_ops = {
.set_clock = sdhci_pci_o2_set_clock,
.enable_dma = sdhci_pci_enable_dma,
.set_bus_width = sdhci_set_bus_width,
.reset = sdhci_reset,
.set_uhs_signaling = sdhci_set_uhs_signaling,
};
const struct sdhci_pci_fixes sdhci_o2 = {
.probe = sdhci_pci_o2_probe,
.quirks = SDHCI_QUIRK_NO_ENDATTR_IN_NOPDESC,
.probe_slot = sdhci_pci_o2_probe_slot,
#ifdef CONFIG_PM_SLEEP
.resume = sdhci_pci_o2_resume,
#endif
.ops = &sdhci_pci_o2_ops,
};
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