[PATCH 5.5 173/257] mmc: sdhci-of-esdhc: fix esdhc_reset() for different controller versions

From: Greg Kroah-Hartman
Date: Thu Apr 16 2020 - 09:56:30 EST


From: Yangbo Lu <yangbo.lu@xxxxxxx>

commit 2aa3d826adb578b26629a79b775a552cfe3fedf7 upstream.

This patch is to fix operating in esdhc_reset() for different
controller versions, and to add bus-width restoring after data
reset for eSDHC (verdor version <= 2.2).

Also add annotation for understanding.

Signed-off-by: Yangbo Lu <yangbo.lu@xxxxxxx>
Acked-by: Adrian Hunter <adrian.hunter@xxxxxxxxx>
Link: https://lore.kernel.org/r/20200108040713.38888-1-yangbo.lu@xxxxxxx
Signed-off-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/mmc/host/sdhci-of-esdhc.c | 43 ++++++++++++++++++++++++++++++++++----
1 file changed, 39 insertions(+), 4 deletions(-)

--- a/drivers/mmc/host/sdhci-of-esdhc.c
+++ b/drivers/mmc/host/sdhci-of-esdhc.c
@@ -758,23 +758,58 @@ static void esdhc_reset(struct sdhci_hos
{
struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
struct sdhci_esdhc *esdhc = sdhci_pltfm_priv(pltfm_host);
- u32 val;
+ u32 val, bus_width = 0;

+ /*
+ * Add delay to make sure all the DMA transfers are finished
+ * for quirk.
+ */
if (esdhc->quirk_delay_before_data_reset &&
(mask & SDHCI_RESET_DATA) &&
(host->flags & SDHCI_REQ_USE_DMA))
mdelay(5);

+ /*
+ * Save bus-width for eSDHC whose vendor version is 2.2
+ * or lower for data reset.
+ */
+ if ((mask & SDHCI_RESET_DATA) &&
+ (esdhc->vendor_ver <= VENDOR_V_22)) {
+ val = sdhci_readl(host, ESDHC_PROCTL);
+ bus_width = val & ESDHC_CTRL_BUSWIDTH_MASK;
+ }
+
sdhci_reset(host, mask);

- sdhci_writel(host, host->ier, SDHCI_INT_ENABLE);
- sdhci_writel(host, host->ier, SDHCI_SIGNAL_ENABLE);
+ /*
+ * Restore bus-width setting and interrupt registers for eSDHC
+ * whose vendor version is 2.2 or lower for data reset.
+ */
+ if ((mask & SDHCI_RESET_DATA) &&
+ (esdhc->vendor_ver <= VENDOR_V_22)) {
+ val = sdhci_readl(host, ESDHC_PROCTL);
+ val &= ~ESDHC_CTRL_BUSWIDTH_MASK;
+ val |= bus_width;
+ sdhci_writel(host, val, ESDHC_PROCTL);
+
+ sdhci_writel(host, host->ier, SDHCI_INT_ENABLE);
+ sdhci_writel(host, host->ier, SDHCI_SIGNAL_ENABLE);
+ }

- if (mask & SDHCI_RESET_ALL) {
+ /*
+ * Some bits have to be cleaned manually for eSDHC whose spec
+ * version is higher than 3.0 for all reset.
+ */
+ if ((mask & SDHCI_RESET_ALL) &&
+ (esdhc->spec_ver >= SDHCI_SPEC_300)) {
val = sdhci_readl(host, ESDHC_TBCTL);
val &= ~ESDHC_TB_EN;
sdhci_writel(host, val, ESDHC_TBCTL);

+ /*
+ * Initialize eSDHC_DLLCFG1[DLL_PD_PULSE_STRETCH_SEL] to
+ * 0 for quirk.
+ */
if (esdhc->quirk_unreliable_pulse_detection) {
val = sdhci_readl(host, ESDHC_DLLCFG1);
val &= ~ESDHC_DLL_PD_PULSE_STRETCH_SEL;