[PATCH 0/2] adds quirk SDHCI_QUIRK2_CLOCK_DIV_ZERO_BROKEN

[PATCH 0/2] adds quirk SDHCI_QUIRK2_CLOCK_DIV_ZERO_BROKEN

[Suneel Garapati]

This quirk will support controllers whose clock divider zero is broken
and if the calculation results to zero, forcing the divider to next value.
This is tested on zynq ep108 and enables support for UHS cards where formatting
cards fail. Added few quirks to arasan platform driver as the base clock reported in
registers is broken and preset values are broken too and tested on zynq ep108
platform. max-frequency devicetree parameter is alternative to get upper limit .

Suneel Garapati (2):
  drivers: mmc: add quirk SDHCI_QUIRK_CLOCK_DIV_ZERO_BROKEN
  drivers: mmc: add quirks for broken clock base

 drivers/mmc/host/sdhci-of-arasan.c | 3 +++
 drivers/mmc/host/sdhci.c           | 4 ++++
 drivers/mmc/host/sdhci.h           | 2 ++
 3 files changed, 9 insertions(+)

--
2.1.2

[PATCH 1/2] drivers: mmc: add quirk SDHCI_QUIRK_CLOCK_DIV_ZERO_BROKEN

[Suneel Garapati]

adds quirk for controllers whose clock divider zero is broken,
sdhci_set_clock function will incorporate this modification.

Signed-off-by: Suneel Garapati <suneel.garapati@xilinx.com>
---
 drivers/mmc/host/sdhci.c | 4 ++++
 drivers/mmc/host/sdhci.h | 2 ++
 2 files changed, 6 insertions(+)

diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index 1b4861d..087327e 100644
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -1210,6 +1210,10 @@ void sdhci_set_clock(struct sdhci_host *host, unsigned int clock)
			}
			real_div = div;
			div >>= 1;
+			if ((host->quirks2 & SDHCI_QUIRK2_CLOCK_DIV_ZERO_BROKEN)
+				&& !div && host->max_clk <= 25000000) {
+				div = 1;
+			}
		}
	} else {
		/* Version 2.00 divisors must be a power of 2. */
diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h
index 5521d29..67046ca 100644
--- a/drivers/mmc/host/sdhci.h
+++ b/drivers/mmc/host/sdhci.h
@@ -409,6 +409,8 @@ struct sdhci_host {
 #define SDHCI_QUIRK2_SUPPORT_SINGLE			(1<<13)
 /* Controller broken with using ACMD23 */
 #define SDHCI_QUIRK2_ACMD23_BROKEN			(1<<14)
+/* Broken Clock divider zero in controller */
+#define SDHCI_QUIRK2_CLOCK_DIV_ZERO_BROKEN		(1<<15)

	int irq;		/* Device IRQ */
	void __iomem *ioaddr;	/* Mapped address */
--
2.1.2

[PATCH 2/2] drivers: mmc: add quirks for broken clock base

[Suneel Garapati]

adding SDHCI_QUIRK_CAP_CLOCK_BASE_BROKEN,SDHCI_QUIRK2_PRESET_VALUE_BROKEN
flags for arasan sdhc.

Signed-off-by: Suneel Garapati <suneel.garapati@xilinx.com>
---
 drivers/mmc/host/sdhci-of-arasan.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/mmc/host/sdhci-of-arasan.c b/drivers/mmc/host/sdhci-of-arasan.c
index 21c0c08..ef5a7d2 100644
--- a/drivers/mmc/host/sdhci-of-arasan.c
+++ b/drivers/mmc/host/sdhci-of-arasan.c
@@ -63,6 +63,9 @@ static struct sdhci_ops sdhci_arasan_ops = {

 static struct sdhci_pltfm_data sdhci_arasan_pdata = {
	.ops = &sdhci_arasan_ops,
+	.quirks = SDHCI_QUIRK_CAP_CLOCK_BASE_BROKEN,
+	.quirks2 = SDHCI_QUIRK2_PRESET_VALUE_BROKEN |
+			SDHCI_QUIRK2_CLOCK_DIV_ZERO_BROKEN,
 };

 #ifdef CONFIG_PM_SLEEP
--
2.1.2

Re: [PATCH 1/2] drivers: mmc: add quirk SDHCI_QUIRK_CLOCK_DIV_ZERO_BROKEN

[Jaehoon Chung]

Hi,

On 06/09/2015 04:31 PM, Suneel Garapati wrote:
> adds quirk for controllers whose clock divider zero is broken,
> sdhci_set_clock function will incorporate this modification.
> 
> Signed-off-by: Suneel Garapati <suneel.garapati@xilinx.com>
> ---
>  drivers/mmc/host/sdhci.c | 4 ++++
>  drivers/mmc/host/sdhci.h | 2 ++
>  2 files changed, 6 insertions(+)
> 
> diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
> index 1b4861d..087327e 100644
> --- a/drivers/mmc/host/sdhci.c
> +++ b/drivers/mmc/host/sdhci.c
> @@ -1210,6 +1210,10 @@ void sdhci_set_clock(struct sdhci_host *host, unsigned int clock)
> 			}
> 			real_div = div;
> 			div >>= 1;
> +			if ((host->quirks2 & SDHCI_QUIRK2_CLOCK_DIV_ZERO_BROKEN)
> +				&& !div && host->max_clk <= 25000000) {
> +				div = 1;
> +			}

I can't understand fully. how can it be broken for divider zero?
When formatting error is occurred, do you check really clock value?
I think your patch looks like just hard-coding for control clock.

Best Regards,
Jaehoon Chung

> 		}
> 	} else {
> 		/* Version 2.00 divisors must be a power of 2. */
> diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h
> index 5521d29..67046ca 100644
> --- a/drivers/mmc/host/sdhci.h
> +++ b/drivers/mmc/host/sdhci.h
> @@ -409,6 +409,8 @@ struct sdhci_host {
>  #define SDHCI_QUIRK2_SUPPORT_SINGLE			(1<<13)
>  /* Controller broken with using ACMD23 */
>  #define SDHCI_QUIRK2_ACMD23_BROKEN			(1<<14)
> +/* Broken Clock divider zero in controller */
> +#define SDHCI_QUIRK2_CLOCK_DIV_ZERO_BROKEN		(1<<15)
> 
> 	int irq;		/* Device IRQ */
> 	void __iomem *ioaddr;	/* Mapped address */
> --
> 2.1.2
> --
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> 

Re: [PATCH 0/2] adds quirk SDHCI_QUIRK2_CLOCK_DIV_ZERO_BROKEN

[Ulf Hansson]

On 9 June 2015 at 09:31, Suneel Garapati <suneel.garapati@xilinx.com> wrote:
> This quirk will support controllers whose clock divider zero is broken
> and if the calculation results to zero, forcing the divider to next value.
> This is tested on zynq ep108 and enables support for UHS cards where formatting
> cards fail. Added few quirks to arasan platform driver as the base clock reported in
> registers is broken and preset values are broken too and tested on zynq ep108
> platform. max-frequency devicetree parameter is alternative to get upper limit .
>
> Suneel Garapati (2):
>   drivers: mmc: add quirk SDHCI_QUIRK_CLOCK_DIV_ZERO_BROKEN
>   drivers: mmc: add quirks for broken clock base
>
>  drivers/mmc/host/sdhci-of-arasan.c | 3 +++
>  drivers/mmc/host/sdhci.c           | 4 ++++
>  drivers/mmc/host/sdhci.h           | 2 ++
>  3 files changed, 9 insertions(+)
>
> --
> 2.1.2

Thanks, applied!

Do note that both patches had checkpatch errors, which complained
about the patch format.
I decided to fix them, but next time please make sure to run checkpatch.

Also, I changed the prefix of patch1 to "mmc: sdhci: and for patch 2
to "mmc: sdhci-of-arasan".

Kind regards
Uffe