From: Shirley Her <shirley....@bayhubtech.com> commit 1ad9f88014ae1d5abccb6fe930bc4c5c311bdc05 upstream.
Force chip enter L0 power state during SDR104 HW tuning to avoid tuning failure Signed-off-by: Shirley Her <shirley....@bayhubtech.com> Link: https://lore.kernel.org/r/20210206014051.3418-1-shirley....@bayhubtech.com Fixes: 7b7d897e8898 ("mmc: sdhci-pci-o2micro: Add HW tuning for SDR104 mode") Cc: sta...@vger.kernel.org Signed-off-by: Ulf Hansson <ulf.hans...@linaro.org> Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org> --- drivers/mmc/host/sdhci-pci-o2micro.c | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+) --- a/drivers/mmc/host/sdhci-pci-o2micro.c +++ b/drivers/mmc/host/sdhci-pci-o2micro.c @@ -33,6 +33,8 @@ #define O2_SD_ADMA2 0xE7 #define O2_SD_INF_MOD 0xF1 #define O2_SD_MISC_CTRL4 0xFC +#define O2_SD_MISC_CTRL 0x1C0 +#define O2_SD_PWR_FORCE_L0 0x0002 #define O2_SD_TUNING_CTRL 0x300 #define O2_SD_PLL_SETTING 0x304 #define O2_SD_MISC_SETTING 0x308 @@ -300,6 +302,8 @@ static int sdhci_o2_execute_tuning(struc { struct sdhci_host *host = mmc_priv(mmc); int current_bus_width = 0; + u32 scratch32 = 0; + u16 scratch = 0; /* * This handler only implements the eMMC tuning that is specific to @@ -312,6 +316,17 @@ static int sdhci_o2_execute_tuning(struc if (WARN_ON((opcode != MMC_SEND_TUNING_BLOCK_HS200) && (opcode != MMC_SEND_TUNING_BLOCK))) return -EINVAL; + + /* Force power mode enter L0 */ + scratch = sdhci_readw(host, O2_SD_MISC_CTRL); + scratch |= O2_SD_PWR_FORCE_L0; + sdhci_writew(host, scratch, O2_SD_MISC_CTRL); + + /* wait DLL lock, timeout value 5ms */ + if (readx_poll_timeout(sdhci_o2_pll_dll_wdt_control, host, + scratch32, (scratch32 & O2_DLL_LOCK_STATUS), 1, 5000)) + pr_warn("%s: DLL can't lock in 5ms after force L0 during tuning.\n", + mmc_hostname(host->mmc)); /* * Judge the tuning reason, whether caused by dll shift * If cause by dll shift, should call sdhci_o2_dll_recovery @@ -344,6 +359,11 @@ static int sdhci_o2_execute_tuning(struc sdhci_set_bus_width(host, current_bus_width); } + /* Cancel force power mode enter L0 */ + scratch = sdhci_readw(host, O2_SD_MISC_CTRL); + scratch &= ~(O2_SD_PWR_FORCE_L0); + sdhci_writew(host, scratch, O2_SD_MISC_CTRL); + sdhci_reset(host, SDHCI_RESET_CMD); sdhci_reset(host, SDHCI_RESET_DATA);
