[PATCH V5 2/3] mmc: sdhci: Fix O2 Host data read/write DLL Lock Phase shift issue

From: Shirley Her (SC)
Date: Wed Aug 07 2019 - 17:09:59 EST


Fix data read/write error in HS200 mode due to chip DLL lock phase shift

Signed-off-by:Shirley Her <shirley.her@xxxxxxxxxxxxxx>
---
change in V5:
1. split 2 patches into 3 patches
2. make dll_adjust_count start from 0
3. fix ret overwritten issue
4. use break instead of goto

change in V4:
1. add a bug fix for V3

change in V3:
1. add more explanation in dll_recovery and execute_tuning function
2. move dll_adjust_count to O2_host struct
3. fix some coding style error
4. renaming O2_PLL_WDT_CONTROL1 TO O2_PLL_DLL_WDT_CONTROL1

change in V2:
1. use usleep_range instead of udelay
2. move dll_adjust_count to sdhci-pci-o2micro.c

chagne in V1:
1. add error recovery function to relock DLL with correct phase
2. retuning HS200 after DLL locked
---
drivers/mmc/host/sdhci-pci-o2micro.c | 188 ++++++++++++++++++-----------------
1 file changed, 95 insertions(+), 93 deletions(-)

diff --git a/drivers/mmc/host/sdhci-pci-o2micro.c b/drivers/mmc/host/sdhci-pci-o2micro.c
index b3a33d9..c780888 100644
--- a/drivers/mmc/host/sdhci-pci-o2micro.c
+++ b/drivers/mmc/host/sdhci-pci-o2micro.c
@@ -58,6 +58,101 @@

#define O2_SD_DETECT_SETTING 0x324

+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_DLL_WDT_CONTROL1);
+ scratch32 |= O2_PLL_SOFT_RESET;
+ sdhci_writel(host, scratch32, O2_PLL_DLL_WDT_CONTROL1);
+ udelay(1);
+ scratch32 &= ~(O2_PLL_SOFT_RESET);
+ sdhci_writel(host, scratch32, O2_PLL_DLL_WDT_CONTROL1);
+
+ /* PLL force active */
+ scratch32 |= O2_PLL_FORCE_ACTIVE;
+ sdhci_writel(host, scratch32, O2_PLL_DLL_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_DLL_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_DLL_WDT_CONTROL1);
+ scratch32 &= ~O2_PLL_FORCE_ACTIVE;
+ sdhci_writel(host, scratch32, O2_PLL_DLL_WDT_CONTROL1);
+}
+
+static int sdhci_o2_get_cd(struct mmc_host *mmc)
+{
+ struct sdhci_host *host = mmc_priv(mmc);
+
+ if (!(sdhci_readw(host, O2_PLL_DLL_WDT_CONTROL1) & O2_PLL_LOCK_STATUS))
+ sdhci_o2_enable_internal_clock(host);
+
+ return !!(sdhci_readl(host, SDHCI_PRESENT_STATE) & SDHCI_CARD_PRESENT);
+}
+
+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 sdhci_o2_set_tuning_mode(struct sdhci_host *host)
{
u16 reg;
@@ -136,19 +231,6 @@ static int sdhci_o2_execute_tuning(struct mmc_host *mmc, u32 opcode)
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;
@@ -284,86 +366,6 @@ static void sdhci_pci_o2_enable_msi(struct sdhci_pci_chip *chip,
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_DLL_WDT_CONTROL1);
- scratch32 |= O2_PLL_SOFT_RESET;
- sdhci_writel(host, scratch32, O2_PLL_DLL_WDT_CONTROL1);
- udelay(1);
- scratch32 &= ~(O2_PLL_SOFT_RESET);
- sdhci_writel(host, scratch32, O2_PLL_DLL_WDT_CONTROL1);
-
- /* PLL force active */
- scratch32 |= O2_PLL_FORCE_ACTIVE;
- sdhci_writel(host, scratch32, O2_PLL_DLL_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_DLL_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_DLL_WDT_CONTROL1);
- scratch32 &= ~O2_PLL_FORCE_ACTIVE;
- sdhci_writel(host, scratch32, O2_PLL_DLL_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 */
--
2.7.4