Fix data read/write error in HS200 mode due to chip DLL lock phase shift
Signed-off-by:Shirley Her <shirley....@bayhubtech.com>
---
change in V6:
1. define constant by using array size
2. add more explanation for the code
3. fix loop forever code error
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 | 128 ++++++++++++++++++++++++++++++++++-
1 file changed, 127 insertions(+), 1 deletion(-)
diff --git a/drivers/mmc/host/sdhci-pci-o2micro.c
b/drivers/mmc/host/sdhci-pci-o2micro.c
index c780888..8cb516d 100644
--- a/drivers/mmc/host/sdhci-pci-o2micro.c
+++ b/drivers/mmc/host/sdhci-pci-o2micro.c
@@ -55,9 +55,18 @@
#define O2_PLL_FORCE_ACTIVE BIT(18)
#define O2_PLL_LOCK_STATUS BIT(14)
#define O2_PLL_SOFT_RESET BIT(12)
+#define O2_DLL_LOCK_STATUS BIT(11)
#define O2_SD_DETECT_SETTING 0x324
+static const u32 dmdn_table[] = {0x2B1C0000,
+ 0x2C1A0000, 0x371B0000, 0x35100000};
+#define DMDN_SZ ARRAY_SIZE(dmdn_table)
+
+struct o2_host {
+ u8 dll_adjust_count;
+};
+
static void sdhci_o2_wait_card_detect_stable(struct sdhci_host *host)
{
ktime_t timeout;
@@ -153,6 +162,38 @@ static void o2_pci_set_baseclk(struct sdhci_pci_chip
*chip, u32 value)
O2_SD_PLL_SETTING, scratch_32);
}
+/*
+ * This function is used to detect dll lock status.
+ * Before detect, need wait 5ms for dll status stable.
+ * In order to detect the toggle of dll lock status bit,
+ * we should fast polling this bit status without delay.
+ */
+static int sdhci_o2_wait_dll_detect_lock(struct sdhci_host *host)
+{
+ ktime_t timeout;
+ u32 scratch32;
+
+ usleep_range(5000, 6000);
+ scratch32 = sdhci_readl(host, O2_PLL_DLL_WDT_CONTROL1);
+ if (!(scratch32 & O2_DLL_LOCK_STATUS)) {
+ pr_warn("%s: DLL is still unlocked after wait 5ms\n",
+ mmc_hostname(host->mmc));
+ }
+
+ /* Detect 1 s */
+ timeout = ktime_add_ms(ktime_get(), 1000);
+ while (1) {
+ bool timedout = ktime_after(ktime_get(), timeout);
+
+ scratch32 = sdhci_readl(host, O2_PLL_DLL_WDT_CONTROL1);
+ if (!(scratch32 & O2_DLL_LOCK_STATUS))
+ return 0;
+
+ if (timedout)
+ return 1;
+ }
+}
+
static void sdhci_o2_set_tuning_mode(struct sdhci_host *host)
{
u16 reg;
@@ -190,6 +231,78 @@ static void __sdhci_o2_execute_tuning(struct sdhci_host
*host, u32 opcode)
sdhci_reset_tuning(host);
}
+/*
+ * This function is used to fix o2 dll shift issue.
+ * It isn't necessary to detect card present before recovery.
+ * Firstly, it is used by bht emmc card, which is embedded.
+ * Second, before call recovery card present will be detected
+ * outside of the execute tuning function.
+ */
+static int sdhci_o2_dll_recovery(struct sdhci_host *host)
+{
+ int ret = 0;
+ u8 scratch_8 = 0;
+ u32 scratch_32 = 0;
+ struct sdhci_pci_slot *slot = sdhci_priv(host);
+ struct sdhci_pci_chip *chip = slot->chip;
+ struct o2_host *o2_host = sdhci_pci_priv(slot);
+
+ /* UnLock WP */
+ pci_read_config_byte(chip->pdev,
+ O2_SD_LOCK_WP, &scratch_8);
+ scratch_8 &= 0x7f;
+ pci_write_config_byte(chip->pdev, O2_SD_LOCK_WP, scratch_8);
+ while (o2_host->dll_adjust_count < DMDN_SZ && !ret) {
+ /* Disable clock */
+ sdhci_writeb(host, 0, SDHCI_CLOCK_CONTROL);
+
+ /* PLL software reset */
+ scratch_32 = sdhci_readl(host, O2_PLL_DLL_WDT_CONTROL1);
+ scratch_32 |= O2_PLL_SOFT_RESET;
+ sdhci_writel(host, scratch_32, O2_PLL_DLL_WDT_CONTROL1);
+
+ 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);
+ o2_pci_set_baseclk(chip, dmdn_table[o2_host->dll_adjust_count]);
+
+ /* Enable internal clock */
+ scratch_8 = SDHCI_CLOCK_INT_EN;
+ sdhci_writeb(host, scratch_8, SDHCI_CLOCK_CONTROL);
+
+ if (sdhci_o2_get_cd(host->mmc)) {
+ if (sdhci_o2_wait_dll_detect_lock(host)) {
+ scratch_8 |= SDHCI_CLOCK_CARD_EN;
+ sdhci_writeb(host, scratch_8,
+ SDHCI_CLOCK_CONTROL);
+ ret = 1;
+ } else {
+ pr_warn("%s: DLL unlocked when dll_adjust_count
is %d.\n",
+ mmc_hostname(host->mmc),
+ o2_host->dll_adjust_count);
+ }
+ } else {
+ pr_err("%s: card present detect failed.\n",
+ mmc_hostname(host->mmc));
+ break;
+ }
+
+ o2_host->dll_adjust_count++;
+ }
+ if (!ret && o2_host->dll_adjust_count == DMDN_SZ)
+ pr_err("%s: DLL adjust over max times\n",
+ mmc_hostname(host->mmc));
+ /* Lock WP */
+ pci_read_config_byte(chip->pdev,
+ O2_SD_LOCK_WP, &scratch_8);
+ scratch_8 |= 0x80;
+ pci_write_config_byte(chip->pdev, O2_SD_LOCK_WP, scratch_8);
+ return ret;
+}
+
static int sdhci_o2_execute_tuning(struct mmc_host *mmc, u32 opcode)
{
struct sdhci_host *host = mmc_priv(mmc);
@@ -204,7 +317,16 @@ static int sdhci_o2_execute_tuning(struct mmc_host *mmc,
u32 opcode)
if (WARN_ON(opcode != MMC_SEND_TUNING_BLOCK_HS200))
return -EINVAL;
-
+ /*
+ * Judge the tuning reason, whether caused by dll shift
+ * If cause by dll shift, should call sdhci_o2_dll_recovery
+ */
+ if (!sdhci_o2_wait_dll_detect_lock(host))
+ if (!sdhci_o2_dll_recovery(host)) {
+ pr_err("%s: o2 dll recovery failed\n",
+ mmc_hostname(host->mmc));
+ return -EINVAL;
+ }
/*
* o2 sdhci host didn't support 8bit emmc tuning
*/
@@ -372,6 +494,7 @@ static void sdhci_o2_enable_clk(struct sdhci_host *host,
u16 clk)
clk |= SDHCI_CLOCK_INT_EN;
sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);
+ sdhci_o2_enable_internal_clock(host);
if (sdhci_o2_get_cd(host->mmc)) {
clk |= SDHCI_CLOCK_CARD_EN;
sdhci_writew(host, clk, SDHCI_CLOCK_CONTROL);
@@ -397,12 +520,14 @@ int sdhci_pci_o2_probe_slot(struct sdhci_pci_slot *slot)
{
struct sdhci_pci_chip *chip;
struct sdhci_host *host;
+ struct o2_host *o2_host = sdhci_pci_priv(slot);
u32 reg, caps;
int ret;
chip = slot->chip;
host = slot->host;
+ o2_host->dll_adjust_count = 0;
caps = sdhci_readl(host, SDHCI_CAPABILITIES);
/*
@@ -689,4 +814,5 @@ const struct sdhci_pci_fixes sdhci_o2 = {
.resume = sdhci_pci_o2_resume,
#endif
.ops = &sdhci_pci_o2_ops,
+ .priv_size = sizeof(struct o2_host),
};
--
2.7.4
