projects / thirdparty / kernel / stable-queue.git / blame
| Commit | Line | Data |
|---|---|---|
| fb1f16f1 SL |
1 | From 5a433a915be47c7b5aa8eea21d70b7b086b1a793 Mon Sep 17 00:00:00 2001 |
| 2 | From: Sasha Levin <sashal@kernel.org> | |
| 3 | Date: Tue, 3 Sep 2019 07:51:14 -0400 | |
| 4 | Subject: mmc: sdhci: Fix incorrect switch to HS mode | |
| 5 | ||
| 6 | From: Al Cooper <alcooperx@gmail.com> | |
| 7 | ||
| 8 | [ Upstream commit c894e33ddc1910e14d6f2a2016f60ab613fd8b37 ] | |
| 9 | ||
| 10 | When switching from any MMC speed mode that requires 1.8v | |
| 11 | (HS200, HS400 and HS400ES) to High Speed (HS) mode, the system | |
| 12 | ends up configured for SDR12 with a 50MHz clock which is an illegal | |
| 13 | mode. | |
| 14 | ||
| 15 | This happens because the SDHCI_CTRL_VDD_180 bit in the | |
| 16 | SDHCI_HOST_CONTROL2 register is left set and when this bit is | |
| 17 | set, the speed mode is controlled by the SDHCI_CTRL_UHS field | |
| 18 | in the SDHCI_HOST_CONTROL2 register. The SDHCI_CTRL_UHS field | |
| 19 | will end up being set to 0 (SDR12) by sdhci_set_uhs_signaling() | |
| 20 | because there is no UHS mode being set. | |
| 21 | ||
| 22 | The fix is to change sdhci_set_uhs_signaling() to set the | |
| 23 | SDHCI_CTRL_UHS field to SDR25 (which is the same as HS) for | |
| 24 | any switch to HS mode. | |
| 25 | ||
| 26 | This was found on a new eMMC controller that does strict checking | |
| 27 | of the speed mode and the corresponding clock rate. It caused the | |
| 28 | switch to HS400 mode to fail because part of the sequence to switch | |
| 29 | to HS400 requires a switch from HS200 to HS before going to HS400. | |
| 30 | ||
| 31 | Suggested-by: Adrian Hunter <adrian.hunter@intel.com> | |
| 32 | Signed-off-by: Al Cooper <alcooperx@gmail.com> | |
| 33 | Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> | |
| 34 | Signed-off-by: Sasha Levin <sashal@kernel.org> | |
| 35 | --- | |
| 36 | drivers/mmc/host/sdhci.c | 4 +++- | |
| 37 | 1 file changed, 3 insertions(+), 1 deletion(-) | |
| 38 | ||
| 39 | diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c | |
| 40 | index a5dc5aae973e6..c66e66fbaeb40 100644 | |
| 41 | --- a/drivers/mmc/host/sdhci.c | |
| 42 | +++ b/drivers/mmc/host/sdhci.c | |
| 43 | @@ -1849,7 +1849,9 @@ void sdhci_set_uhs_signaling(struct sdhci_host *host, unsigned timing) | |
| 44 | ctrl_2 |= SDHCI_CTRL_UHS_SDR104; | |
| 45 | else if (timing == MMC_TIMING_UHS_SDR12) | |
| 46 | ctrl_2 |= SDHCI_CTRL_UHS_SDR12; | |
| 47 | - else if (timing == MMC_TIMING_UHS_SDR25) | |
| 48 | + else if (timing == MMC_TIMING_SD_HS || | |
| 49 | + timing == MMC_TIMING_MMC_HS || | |
| 50 | + timing == MMC_TIMING_UHS_SDR25) | |
| 51 | ctrl_2 |= SDHCI_CTRL_UHS_SDR25; | |
| 52 | else if (timing == MMC_TIMING_UHS_SDR50) | |
| 53 | ctrl_2 |= SDHCI_CTRL_UHS_SDR50; | |
| 54 | -- | |
| 55 | 2.20.1 | |
| 56 |