[PATCH AUTOSEL 6.1 78/85] mmc: sdhci-tegra: Issue CMD and DAT resets together

From: Sasha Levin
Date: Sun Dec 18 2022 - 11:19:12 EST


From: Prathamesh Shete <pshete@xxxxxxxxxx>

[ Upstream commit acc13958c2b2623c17e2450b8cd6881b698756d3 ]

In case of error condition to avoid system crash Tegra SDMMC controller
requires CMD and DAT resets issued together. SDHCI controller FSM goes
into bad state due to rapid SD card hot-plug event. Issuing reset on the
CMD FSM before DATA FSM results in kernel panic, hence add support to
issue CMD and DAT resets together.

This is applicable to Tegra186 and later chips.

Signed-off-by: Aniruddha TVS Rao <anrao@xxxxxxxxxx>
Signed-off-by: Prathamesh Shete <pshete@xxxxxxxxxx>
Acked-by: Adrian Hunter <adrian.hunter@xxxxxxxxx>
Acked-by: Thierry Reding <treding@xxxxxxxxxx>
Signed-off-by: Thierry Reding <treding@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20221206165945.3551774-7-thierry.reding@xxxxxxxxx
Signed-off-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/mmc/host/sdhci-tegra.c | 3 ++-
drivers/mmc/host/sdhci.c | 5 +++++
drivers/mmc/host/sdhci.h | 2 ++
3 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/drivers/mmc/host/sdhci-tegra.c b/drivers/mmc/host/sdhci-tegra.c
index c71000a07656..1adaa94c31ac 100644
--- a/drivers/mmc/host/sdhci-tegra.c
+++ b/drivers/mmc/host/sdhci-tegra.c
@@ -1526,7 +1526,8 @@ static const struct sdhci_pltfm_data sdhci_tegra186_pdata = {
SDHCI_QUIRK_NO_HISPD_BIT |
SDHCI_QUIRK_BROKEN_ADMA_ZEROLEN_DESC |
SDHCI_QUIRK_CAP_CLOCK_BASE_BROKEN,
- .quirks2 = SDHCI_QUIRK2_PRESET_VALUE_BROKEN,
+ .quirks2 = SDHCI_QUIRK2_PRESET_VALUE_BROKEN |
+ SDHCI_QUIRK2_ISSUE_CMD_DAT_RESET_TOGETHER,
.ops = &tegra186_sdhci_ops,
};

diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index c7ad32a75b57..632341911b6e 100644
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -270,6 +270,11 @@ enum sdhci_reset_reason {

static void sdhci_reset_for_reason(struct sdhci_host *host, enum sdhci_reset_reason reason)
{
+ if (host->quirks2 & SDHCI_QUIRK2_ISSUE_CMD_DAT_RESET_TOGETHER) {
+ sdhci_do_reset(host, SDHCI_RESET_CMD | SDHCI_RESET_DATA);
+ return;
+ }
+
switch (reason) {
case SDHCI_RESET_FOR_INIT:
sdhci_do_reset(host, SDHCI_RESET_CMD | SDHCI_RESET_DATA);
diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h
index 87a3aaa07438..5ce7cdcc192f 100644
--- a/drivers/mmc/host/sdhci.h
+++ b/drivers/mmc/host/sdhci.h
@@ -478,6 +478,8 @@ struct sdhci_host {
* block count.
*/
#define SDHCI_QUIRK2_USE_32BIT_BLK_CNT (1<<18)
+/* Issue CMD and DATA reset together */
+#define SDHCI_QUIRK2_ISSUE_CMD_DAT_RESET_TOGETHER (1<<19)

int irq; /* Device IRQ */
void __iomem *ioaddr; /* Mapped address */
--
2.35.1