[PATCH] mmc: sdhci-of-at91: wait for calibration done before proceed

Subsystems: multimedia card (mmc), secure digital (sd) and sdio subsystem, secure digital host controller interface (sdhci) driver, secure digital host controller interface (sdhci) microchip driver, the rest

STALE1835d

3 messages, 3 authors, 2021-09-23 · open the first message on its own page

[PATCH] mmc: sdhci-of-at91: wait for calibration done before proceed

From: Claudiu Beznea <hidden>
Date: 2021-09-15 10:30:14 

Datasheet specifies that at the end of calibration the SDMMC_CALCR_EN
bit will be cleared. No commands should be send before calibration is
done.

Fixes: dbdea70f71d67 ("mmc: sdhci-of-at91: fix CALCR register being rewritten")
Fixes: 727d836a375ad ("mmc: sdhci-of-at91: add DT property to enable calibration on full reset")
Signed-off-by: Claudiu Beznea <redacted>
---
 drivers/mmc/host/sdhci-of-at91.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/drivers/mmc/host/sdhci-of-at91.c b/drivers/mmc/host/sdhci-of-at91.c
index 5564d7b23e7c..2b28711e039d 100644
--- a/drivers/mmc/host/sdhci-of-at91.c
+++ b/drivers/mmc/host/sdhci-of-at91.c
@@ -114,6 +114,8 @@ static void sdhci_at91_reset(struct sdhci_host *host, u8 mask)
 {
 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
 	struct sdhci_at91_priv *priv = sdhci_pltfm_priv(pltfm_host);
+	unsigned long timeout = jiffies + msecs_to_jiffies(20);
+	unsigned int tmp;
 
 	sdhci_reset(host, mask);
 
@@ -126,6 +128,14 @@ static void sdhci_at91_reset(struct sdhci_host *host, u8 mask)
 
 		sdhci_writel(host, calcr | SDMMC_CALCR_ALWYSON | SDMMC_CALCR_EN,
 			     SDMMC_CALCR);
+
+		do {
+			tmp = sdhci_readl(host, SDMMC_CALCR);
+		} while (time_before(jiffies, timeout) &&
+			 (tmp & SDMMC_CALCR_EN));
+
+		if (tmp & SDMMC_CALCR_EN)
+			dev_err(mmc_dev(host->mmc), "Failed to calibrate\n");
 	}
 }
 
-- 
2.25.1


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Re: [PATCH] mmc: sdhci-of-at91: wait for calibration done before proceed

From: Nicolas Ferre <nicolas.ferre@microchip.com>
Date: 2021-09-15 12:04:17 

On 15/09/2021 at 12:28, Claudiu Beznea wrote:
Datasheet specifies that at the end of calibration the SDMMC_CALCR_EN
bit will be cleared. No commands should be send before calibration is
done.

Fixes: dbdea70f71d67 ("mmc: sdhci-of-at91: fix CALCR register being rewritten")
Fixes: 727d836a375ad ("mmc: sdhci-of-at91: add DT property to enable calibration on full reset")
Signed-off-by: Claudiu Beznea <redacted>
Indeed, needed. Thanks Claudiu,
Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com>

Best regards,
  Nicolas
quoted hunk
---
  drivers/mmc/host/sdhci-of-at91.c | 10 ++++++++++
  1 file changed, 10 insertions(+)

diff --git a/drivers/mmc/host/sdhci-of-at91.c b/drivers/mmc/host/sdhci-of-at91.c
index 5564d7b23e7c..2b28711e039d 100644
--- a/drivers/mmc/host/sdhci-of-at91.c
+++ b/drivers/mmc/host/sdhci-of-at91.c
@@ -114,6 +114,8 @@ static void sdhci_at91_reset(struct sdhci_host *host, u8 mask)
  {
  	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
  	struct sdhci_at91_priv *priv = sdhci_pltfm_priv(pltfm_host);
+	unsigned long timeout = jiffies + msecs_to_jiffies(20);
+	unsigned int tmp;
  
  	sdhci_reset(host, mask);
  
@@ -126,6 +128,14 @@ static void sdhci_at91_reset(struct sdhci_host *host, u8 mask)
  
  		sdhci_writel(host, calcr | SDMMC_CALCR_ALWYSON | SDMMC_CALCR_EN,
  			     SDMMC_CALCR);
+
+		do {
+			tmp = sdhci_readl(host, SDMMC_CALCR);
+		} while (time_before(jiffies, timeout) &&
+			 (tmp & SDMMC_CALCR_EN));
+
+		if (tmp & SDMMC_CALCR_EN)
+			dev_err(mmc_dev(host->mmc), "Failed to calibrate\n");
  	}
  }
  

-- 
Nicolas Ferre

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Re: [PATCH] mmc: sdhci-of-at91: wait for calibration done before proceed

From: Adrian Hunter <adrian.hunter@intel.com>
Date: 2021-09-23 09:02:32 

On 15/09/21 1:28 pm, Claudiu Beznea wrote:
quoted hunk
Datasheet specifies that at the end of calibration the SDMMC_CALCR_EN
bit will be cleared. No commands should be send before calibration is
done.

Fixes: dbdea70f71d67 ("mmc: sdhci-of-at91: fix CALCR register being rewritten")
Fixes: 727d836a375ad ("mmc: sdhci-of-at91: add DT property to enable calibration on full reset")
Signed-off-by: Claudiu Beznea <redacted>
---
 drivers/mmc/host/sdhci-of-at91.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/drivers/mmc/host/sdhci-of-at91.c b/drivers/mmc/host/sdhci-of-at91.c
index 5564d7b23e7c..2b28711e039d 100644
--- a/drivers/mmc/host/sdhci-of-at91.c
+++ b/drivers/mmc/host/sdhci-of-at91.c
@@ -114,6 +114,8 @@ static void sdhci_at91_reset(struct sdhci_host *host, u8 mask)
 {
 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
 	struct sdhci_at91_priv *priv = sdhci_pltfm_priv(pltfm_host);
+	unsigned long timeout = jiffies + msecs_to_jiffies(20);
+	unsigned int tmp;
 
 	sdhci_reset(host, mask);
 
@@ -126,6 +128,14 @@ static void sdhci_at91_reset(struct sdhci_host *host, u8 mask)
 
 		sdhci_writel(host, calcr | SDMMC_CALCR_ALWYSON | SDMMC_CALCR_EN,
 			     SDMMC_CALCR);
+
+		do {
+			tmp = sdhci_readl(host, SDMMC_CALCR);
+		} while (time_before(jiffies, timeout) &&
+			 (tmp & SDMMC_CALCR_EN));
+
+		if (tmp & SDMMC_CALCR_EN)
+			dev_err(mmc_dev(host->mmc), "Failed to calibrate\n");
Please use a polling macro (include <linux/iopoll.h>)
i.e.

		if (read_poll_timeout(sdhci_readl, tmp, !(tmp & SDMMC_CALCR_EN),
				      10, 20000, false, host, SDMMC_CALCR))
			dev_err(mmc_dev(host->mmc), "Failed to calibrate\n");



 	}
 }
 

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