From b7dfa695afc40d5396ed84b9f25aa3754de23e39 Mon Sep 17 00:00:00 2001 From: Trac Hoang Date: Thu, 9 May 2019 10:24:26 -0700 Subject: mmc: sdhci-iproc: cygnus: Set NO_HISPD bit to fix HS50 data hold time problem The iproc host eMMC/SD controller hold time does not meet the specification in the HS50 mode. This problem can be mitigated by disabling the HISPD bit; thus forcing the controller output data to be driven on the falling clock edges rather than the rising clock edges. This change applies only to the Cygnus platform. Stable tag (v4.12+) chosen to assist stable kernel maintainers so that the change does not produce merge conflicts backporting to older kernel versions. In reality, the timing bug existed since the driver was first introduced but there is no need for this driver to be supported in kernel versions that old. Cc: stable@vger.kernel.org # v4.12+ Signed-off-by: Trac Hoang Signed-off-by: Scott Branden Acked-by: Adrian Hunter Signed-off-by: Ulf Hansson --- drivers/mmc/host/sdhci-iproc.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'drivers') diff --git a/drivers/mmc/host/sdhci-iproc.c b/drivers/mmc/host/sdhci-iproc.c index 9d12c06c7fd6..9d4071c41c94 100644 --- a/drivers/mmc/host/sdhci-iproc.c +++ b/drivers/mmc/host/sdhci-iproc.c @@ -196,7 +196,8 @@ static const struct sdhci_ops sdhci_iproc_32only_ops = { }; static const struct sdhci_pltfm_data sdhci_iproc_cygnus_pltfm_data = { - .quirks = SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK, + .quirks = SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK | + SDHCI_QUIRK_NO_HISPD_BIT, .quirks2 = SDHCI_QUIRK2_ACMD23_BROKEN | SDHCI_QUIRK2_HOST_OFF_CARD_ON, .ops = &sdhci_iproc_32only_ops, }; -- cgit v1.2.3 From ec0970e0a1b2c807c908d459641a9f9a1be3e130 Mon Sep 17 00:00:00 2001 From: Trac Hoang Date: Thu, 9 May 2019 10:24:27 -0700 Subject: mmc: sdhci-iproc: Set NO_HISPD bit to fix HS50 data hold time problem The iproc host eMMC/SD controller hold time does not meet the specification in the HS50 mode. This problem can be mitigated by disabling the HISPD bit; thus forcing the controller output data to be driven on the falling clock edges rather than the rising clock edges. Stable tag (v4.12+) chosen to assist stable kernel maintainers so that the change does not produce merge conflicts backporting to older kernel versions. In reality, the timing bug existed since the driver was first introduced but there is no need for this driver to be supported in kernel versions that old. Cc: stable@vger.kernel.org # v4.12+ Signed-off-by: Trac Hoang Signed-off-by: Scott Branden Acked-by: Adrian Hunter Signed-off-by: Ulf Hansson --- drivers/mmc/host/sdhci-iproc.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'drivers') diff --git a/drivers/mmc/host/sdhci-iproc.c b/drivers/mmc/host/sdhci-iproc.c index 9d4071c41c94..2feb4ef32035 100644 --- a/drivers/mmc/host/sdhci-iproc.c +++ b/drivers/mmc/host/sdhci-iproc.c @@ -220,7 +220,8 @@ static const struct sdhci_iproc_data iproc_cygnus_data = { static const struct sdhci_pltfm_data sdhci_iproc_pltfm_data = { .quirks = SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK | - SDHCI_QUIRK_MULTIBLOCK_READ_ACMD12, + SDHCI_QUIRK_MULTIBLOCK_READ_ACMD12 | + SDHCI_QUIRK_NO_HISPD_BIT, .quirks2 = SDHCI_QUIRK2_ACMD23_BROKEN, .ops = &sdhci_iproc_ops, }; -- cgit v1.2.3