[PATCH] sdhci: Add new quirk in sdhci driver and update ADMA descriptor build.
Ben Dooks
ben-linux at fluff.org
Tue Sep 15 20:52:36 EDT 2009
On Tue, Sep 08, 2009 at 02:41:59PM +0900, thomas.ab at samsung.com wrote:
> From: Thomas Abraham <thomas.ab at samsung.com>
>
> The s3c6410 sdhci controller does not support the 'End' attribute and
> NOP attribute in the same 8-Byte ADMA descriptor. This patch adds a
> new quirk to identify sdhci host contollers with such behaviour.
> In addition to this, for controllers using the new quirk, the last
> entry in the ADMA descritor table is marked with the 'End' attribute
> (instead of using a NOP descriptor with 'End' attribute).
This is very useful to know, I'd say this would be a useful quirk to
add to the SDHCI driver to see if we can get ADMA working on the S3C64XX
series.
> Signed-off-by: Thomas Abraham <thomas.ab at samsung.com>
> ---
> drivers/mmc/host/sdhci.c | 35 ++++++++++++++++++++++-------------
> drivers/mmc/host/sdhci.h | 2 ++
> 2 files changed, 24 insertions(+), 13 deletions(-)
>
> diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
> index fc96f8c..27a3447 100644
> --- a/drivers/mmc/host/sdhci.c
> +++ b/drivers/mmc/host/sdhci.c
> @@ -487,19 +487,28 @@ static int sdhci_adma_table_pre(struct sdhci_host *host,
> WARN_ON((desc - host->adma_desc) > (128 * 2 + 1) * 4);
> }
>
> - /*
> - * Add a terminating entry.
> - */
> - desc[7] = 0;
> - desc[6] = 0;
> - desc[5] = 0;
> - desc[4] = 0;
> -
> - desc[3] = 0;
> - desc[2] = 0;
> -
> - desc[1] = 0x00;
> - desc[0] = 0x03; /* nop, end, valid */
> + if (host->quirks & SDHCI_QUIRK_NO_ENDATTR_IN_NOPDESC) {
> + /*
> + * Mark the last descriptor as the terminating descriptor
> + */
> + if (desc != host->adma_desc) {
> + desc -= 8;
> + desc[0] |= 0x2; /* end */
> + }
> + } else {
> + /*
> + * Add a terminating entry.
> + */
> + desc[7] = 0;
> + desc[6] = 0;
> + desc[5] = 0;
> + desc[4] = 0;
> +
> + desc[3] = 0;
> + desc[2] = 0;
> + desc[1] = 0x00;
> + desc[0] = 0x03; /* nop, end, valid */
> + }
>
> /*
> * Resync align buffer as we might have changed it.
> diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h
> index c77e9ff..e954116 100644
> --- a/drivers/mmc/host/sdhci.h
> +++ b/drivers/mmc/host/sdhci.h
> @@ -232,6 +232,8 @@ struct sdhci_host {
> #define SDHCI_QUIRK_FORCE_1_BIT_DATA (1<<22)
> /* Controller needs 10ms delay between applying power and clock */
> #define SDHCI_QUIRK_DELAY_AFTER_POWER (1<<23)
> +/* Controller cannot support End Attribute in NOP ADMA descriptor */
> +#define SDHCI_QUIRK_NO_ENDATTR_IN_NOPDESC (1<<24)
>
> int irq; /* Device IRQ */
> void __iomem * ioaddr; /* Mapped address */
> --
> 1.5.3.4
>
>
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--
--
Ben
Q: What's a light-year?
A: One-third less calories than a regular year.
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