[PATCH 4.19 166/276] mmc: sdhci-of-esdhc: add erratum A-009204 support

From: Greg Kroah-Hartman
Date: Wed May 29 2019 - 23:41:29 EST


[ Upstream commit 5dd195522562542bc6ebe6e7bd47890d8b7ca93c ]

In the event of that any data error (like, IRQSTAT[DCE]) occurs
during an eSDHC data transaction where DMA is used for data
transfer to/from the system memory, setting the SYSCTL[RSTD]
register may cause a system hang. If software sets the register
SYSCTL[RSTD] to 1 for error recovery while DMA transferring is
not complete, eSDHC may hang the system bus. This happens because
the software register SYSCTL[RSTD] resets the DMA engine without
waiting for the completion of pending system transactions. This
erratum is to fix this issue.

Signed-off-by: Yinbo Zhu <yinbo.zhu@xxxxxxx>
Acked-by: Adrian Hunter <adrian.hunter@xxxxxxxxx>
Signed-off-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/mmc/host/sdhci-of-esdhc.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/drivers/mmc/host/sdhci-of-esdhc.c b/drivers/mmc/host/sdhci-of-esdhc.c
index b2199d621b8c5..e63d22fb99edf 100644
--- a/drivers/mmc/host/sdhci-of-esdhc.c
+++ b/drivers/mmc/host/sdhci-of-esdhc.c
@@ -643,6 +643,9 @@ static void esdhc_reset(struct sdhci_host *host, u8 mask)
sdhci_writel(host, host->ier, SDHCI_INT_ENABLE);
sdhci_writel(host, host->ier, SDHCI_SIGNAL_ENABLE);

+ if (of_find_compatible_node(NULL, NULL, "fsl,p2020-esdhc"))
+ mdelay(5);
+
if (mask & SDHCI_RESET_ALL) {
val = sdhci_readl(host, ESDHC_TBCTL);
val &= ~ESDHC_TB_EN;
--
2.20.1