[PATCH] mmc: tegra: Mark 64-bit DMA broken on Tegra124

[Thierry Reding <thierry.reding-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>]

From: Thierry Reding <treding-DDmLM1+adcrQT0dZR+AlfA@public.gmane.org>

According to the TRM, the SD/MMC controller on Tegra124 supports 34-bit
addressing, but testing shows that this doesn't work. On a device which
has more than 2 GiB of RAM and LPAE enabled, buffer allocations can use
addresses above the 32-bit boundary.

One way to work around this would be to enable IOMMU physical to virtual
address translations for the SD/MMC controllers, but that's not easy to
implement without breaking existing use-cases. It's also not obvious why
34-bit addressing doesn't work as advertised. In order to fix this for
existing users, add the SDHCI_QUIRK2_BROKEN_64_BIT_DMA quirk for now.

Reported-by: Paul Kocialkowski <contact-W9ppeneeCTY@public.gmane.org>
Signed-off-by: Thierry Reding <treding-DDmLM1+adcrQT0dZR+AlfA@public.gmane.org>
---
 drivers/mmc/host/sdhci-tegra.c | 18 +++++++++++++++++-
 1 file changed, 17 insertions(+), 1 deletion(-)

diff --git a/drivers/mmc/host/sdhci-tegra.c b/drivers/mmc/host/sdhci-tegra.c
index d89200ee017e..a3d045630d0c 100644
--- a/drivers/mmc/host/sdhci-tegra.c
+++ b/drivers/mmc/host/sdhci-tegra.c
@@ -394,6 +394,22 @@ static const struct sdhci_tegra_soc_data soc_data_tegra114 = {
 	.pdata = &sdhci_tegra114_pdata,
 };
 
+static const struct sdhci_pltfm_data sdhci_tegra124_pdata = {
+	.quirks = SDHCI_QUIRK_BROKEN_TIMEOUT_VAL |
+		  SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK |
+		  SDHCI_QUIRK_SINGLE_POWER_WRITE |
+		  SDHCI_QUIRK_NO_HISPD_BIT |
+		  SDHCI_QUIRK_BROKEN_ADMA_ZEROLEN_DESC |
+		  SDHCI_QUIRK_CAP_CLOCK_BASE_BROKEN,
+	.quirks2 = SDHCI_QUIRK2_PRESET_VALUE_BROKEN |
+		   SDHCI_QUIRK2_BROKEN_64_BIT_DMA,
+	.ops  = &tegra114_sdhci_ops,
+};
+
+static const struct sdhci_tegra_soc_data soc_data_tegra124 = {
+	.pdata = &sdhci_tegra124_pdata,
+};
+
 static const struct sdhci_pltfm_data sdhci_tegra210_pdata = {
 	.quirks = SDHCI_QUIRK_BROKEN_TIMEOUT_VAL |
 		  SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK |
@@ -427,7 +443,7 @@ static const struct sdhci_tegra_soc_data soc_data_tegra186 = {
 static const struct of_device_id sdhci_tegra_dt_match[] = {
 	{ .compatible = "nvidia,tegra186-sdhci", .data = &soc_data_tegra186 },
 	{ .compatible = "nvidia,tegra210-sdhci", .data = &soc_data_tegra210 },
-	{ .compatible = "nvidia,tegra124-sdhci", .data = &soc_data_tegra114 },
+	{ .compatible = "nvidia,tegra124-sdhci", .data = &soc_data_tegra124 },
 	{ .compatible = "nvidia,tegra114-sdhci", .data = &soc_data_tegra114 },
 	{ .compatible = "nvidia,tegra30-sdhci", .data = &soc_data_tegra30 },
 	{ .compatible = "nvidia,tegra20-sdhci", .data = &soc_data_tegra20 },
-- 
2.9.3