From 60d53566100abde4acc5504b524bc97f89015690 Mon Sep 17 00:00:00 2001 From: Adrian Hunter Date: Thu, 12 Nov 2020 15:36:56 +0200 Subject: [PATCH] mmc: sdhci-pci: Prefer SDR25 timing for High Speed mode for BYT-based Intel controllers A UHS setting of SDR25 can give better results for High Speed mode. This is because there is no setting corresponding to high speed. Currently SDHCI sets no value, which means zero which is also the setting for SDR12. There was an attempt to change this in sdhci.c but it caused problems for some drivers, so it was reverted and the change was made to sdhci-brcmstb in commit 2fefc7c5f7d16e ("mmc: sdhci-brcmstb: Fix incorrect switch to HS mode"). Several other drivers also do this. Signed-off-by: Adrian Hunter Cc: stable@vger.kernel.org # v5.4+ Link: https://lore.kernel.org/r/20201112133656.20317-1-adrian.hunter@intel.com Signed-off-by: Ulf Hansson --- drivers/mmc/host/sdhci-pci-core.c | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-) diff --git a/drivers/mmc/host/sdhci-pci-core.c b/drivers/mmc/host/sdhci-pci-core.c index 23da7f7..9552708 100644 --- a/drivers/mmc/host/sdhci-pci-core.c +++ b/drivers/mmc/host/sdhci-pci-core.c @@ -665,6 +665,15 @@ static void sdhci_intel_set_power(struct sdhci_host *host, unsigned char mode, } } +static void sdhci_intel_set_uhs_signaling(struct sdhci_host *host, + unsigned int timing) +{ + /* Set UHS timing to SDR25 for High Speed mode */ + if (timing == MMC_TIMING_MMC_HS || timing == MMC_TIMING_SD_HS) + timing = MMC_TIMING_UHS_SDR25; + sdhci_set_uhs_signaling(host, timing); +} + #define INTEL_HS400_ES_REG 0x78 #define INTEL_HS400_ES_BIT BIT(0) @@ -721,7 +730,7 @@ static const struct sdhci_ops sdhci_intel_byt_ops = { .enable_dma = sdhci_pci_enable_dma, .set_bus_width = sdhci_set_bus_width, .reset = sdhci_reset, - .set_uhs_signaling = sdhci_set_uhs_signaling, + .set_uhs_signaling = sdhci_intel_set_uhs_signaling, .hw_reset = sdhci_pci_hw_reset, }; @@ -731,7 +740,7 @@ static const struct sdhci_ops sdhci_intel_glk_ops = { .enable_dma = sdhci_pci_enable_dma, .set_bus_width = sdhci_set_bus_width, .reset = sdhci_cqhci_reset, - .set_uhs_signaling = sdhci_set_uhs_signaling, + .set_uhs_signaling = sdhci_intel_set_uhs_signaling, .hw_reset = sdhci_pci_hw_reset, .irq = sdhci_cqhci_irq, }; -- 2.7.4