* [PATCH] mmc: sdhci-of-esdhc: fixup PRESENT_STATE read
@ 2016-11-10 16:47 Michael Walle
2016-11-11 13:15 ` Adrian Hunter
0 siblings, 1 reply; 3+ messages in thread
From: Michael Walle @ 2016-11-10 16:47 UTC (permalink / raw)
To: linux-kernel
Cc: linux-mmc, Ulf Hansson, Adrian Hunter, yangbo lu, Michael Walle
Since commit 87a18a6a5652 ("mmc: mmc: Use ->card_busy() to detect busy
cards in __mmc_switch()") the ESDHC driver is broken:
mmc0: Card stuck in programming state! __mmc_switch
mmc0: error -110 whilst initialising MMC card
Since this commit __mmc_switch() uses ->card_busy(), which is
sdhci_card_busy() for the esdhc driver. sdhci_card_busy() uses the
PRESENT_STATE register, specifically the DAT0 signal level bit. But the
ESDHC uses a non-conformant PRESENT_STATE register, thus a read fixup is
required to make the driver work again.
Signed-off-by: Michael Walle <michael@walle.cc>
---
drivers/mmc/host/sdhci-of-esdhc.c | 12 ++++++++++++
1 file changed, 12 insertions(+)
diff --git a/drivers/mmc/host/sdhci-of-esdhc.c b/drivers/mmc/host/sdhci-of-esdhc.c
index fb71c86..243fee9 100644
--- a/drivers/mmc/host/sdhci-of-esdhc.c
+++ b/drivers/mmc/host/sdhci-of-esdhc.c
@@ -66,6 +66,18 @@ static u32 esdhc_readl_fixup(struct sdhci_host *host,
return ret;
}
}
+ /*
+ * The DAT[3:0] line signal levels and the CMD line signal level is
+ * not compatible with standard SDHC reegister. Move the corresponding
+ * bits around.
+ */
+ if (spec_reg == SDHCI_PRESENT_STATE) {
+ ret = value & 0xf8000000;
+ ret |= (value >> 4) & SDHCI_DATA_LVL_MASK;
+ ret |= (value << 1) & 0x01000000;
+ return ret;
+ }
+
ret = value;
return ret;
}
--
2.1.4
^ permalink raw reply related [flat|nested] 3+ messages in thread
* Re: [PATCH] mmc: sdhci-of-esdhc: fixup PRESENT_STATE read
2016-11-10 16:47 [PATCH] mmc: sdhci-of-esdhc: fixup PRESENT_STATE read Michael Walle
@ 2016-11-11 13:15 ` Adrian Hunter
2016-11-11 13:25 ` Michael Walle
0 siblings, 1 reply; 3+ messages in thread
From: Adrian Hunter @ 2016-11-11 13:15 UTC (permalink / raw)
To: Michael Walle, linux-kernel; +Cc: linux-mmc, Ulf Hansson, yangbo lu
On 10/11/16 18:47, Michael Walle wrote:
> Since commit 87a18a6a5652 ("mmc: mmc: Use ->card_busy() to detect busy
> cards in __mmc_switch()") the ESDHC driver is broken:
> mmc0: Card stuck in programming state! __mmc_switch
> mmc0: error -110 whilst initialising MMC card
>
> Since this commit __mmc_switch() uses ->card_busy(), which is
> sdhci_card_busy() for the esdhc driver. sdhci_card_busy() uses the
> PRESENT_STATE register, specifically the DAT0 signal level bit. But the
> ESDHC uses a non-conformant PRESENT_STATE register, thus a read fixup is
> required to make the driver work again.
>
> Signed-off-by: Michael Walle <michael@walle.cc>
Could add a Fixes tag here.
> ---
> drivers/mmc/host/sdhci-of-esdhc.c | 12 ++++++++++++
> 1 file changed, 12 insertions(+)
>
> diff --git a/drivers/mmc/host/sdhci-of-esdhc.c b/drivers/mmc/host/sdhci-of-esdhc.c
> index fb71c86..243fee9 100644
> --- a/drivers/mmc/host/sdhci-of-esdhc.c
> +++ b/drivers/mmc/host/sdhci-of-esdhc.c
> @@ -66,6 +66,18 @@ static u32 esdhc_readl_fixup(struct sdhci_host *host,
> return ret;
> }
> }
> + /*
> + * The DAT[3:0] line signal levels and the CMD line signal level is
> + * not compatible with standard SDHC reegister. Move the corresponding
reegister -> register
> + * bits around.
> + */
> + if (spec_reg == SDHCI_PRESENT_STATE) {
> + ret = value & 0xf8000000;
> + ret |= (value >> 4) & SDHCI_DATA_LVL_MASK;
> + ret |= (value << 1) & 0x01000000;
> + return ret;
SDHCI also uses other bits in SDHCI_PRESENT_STATE like SDHCI_CMD_INHIBIT and
SDHCI_DATA_INHIBIT etc, but this looks like all those bits will be zero. Is
that right?
> + }
> +
> ret = value;
> return ret;
> }
>
^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: [PATCH] mmc: sdhci-of-esdhc: fixup PRESENT_STATE read
2016-11-11 13:15 ` Adrian Hunter
@ 2016-11-11 13:25 ` Michael Walle
0 siblings, 0 replies; 3+ messages in thread
From: Michael Walle @ 2016-11-11 13:25 UTC (permalink / raw)
To: Adrian Hunter; +Cc: linux-kernel, linux-mmc, Ulf Hansson, yangbo lu
Am 2016-11-11 14:15, schrieb Adrian Hunter:
> On 10/11/16 18:47, Michael Walle wrote:
>> Since commit 87a18a6a5652 ("mmc: mmc: Use ->card_busy() to detect busy
>> cards in __mmc_switch()") the ESDHC driver is broken:
>> mmc0: Card stuck in programming state! __mmc_switch
>> mmc0: error -110 whilst initialising MMC card
>>
>> Since this commit __mmc_switch() uses ->card_busy(), which is
>> sdhci_card_busy() for the esdhc driver. sdhci_card_busy() uses the
>> PRESENT_STATE register, specifically the DAT0 signal level bit. But
>> the
>> ESDHC uses a non-conformant PRESENT_STATE register, thus a read fixup
>> is
>> required to make the driver work again.
>>
>> Signed-off-by: Michael Walle <michael@walle.cc>
>
> Could add a Fixes tag here.
ah, right, will do :)
>
>> ---
>> drivers/mmc/host/sdhci-of-esdhc.c | 12 ++++++++++++
>> 1 file changed, 12 insertions(+)
>>
>> diff --git a/drivers/mmc/host/sdhci-of-esdhc.c
>> b/drivers/mmc/host/sdhci-of-esdhc.c
>> index fb71c86..243fee9 100644
>> --- a/drivers/mmc/host/sdhci-of-esdhc.c
>> +++ b/drivers/mmc/host/sdhci-of-esdhc.c
>> @@ -66,6 +66,18 @@ static u32 esdhc_readl_fixup(struct sdhci_host
>> *host,
>> return ret;
>> }
>> }
>> + /*
>> + * The DAT[3:0] line signal levels and the CMD line signal level is
>> + * not compatible with standard SDHC reegister. Move the
>> corresponding
>
> reegister -> register
ok
>
>> + * bits around.
>> + */
>> + if (spec_reg == SDHCI_PRESENT_STATE) {
>> + ret = value & 0xf8000000;
>> + ret |= (value >> 4) & SDHCI_DATA_LVL_MASK;
>> + ret |= (value << 1) & 0x01000000;
>> + return ret;
>
> SDHCI also uses other bits in SDHCI_PRESENT_STATE like
> SDHCI_CMD_INHIBIT and
> SDHCI_DATA_INHIBIT etc, but this looks like all those bits will be
> zero. Is
> that right?
ugh, thanks for spotting that. actually all lower bits should be taken
from the original value. Therefore the first statement should be
ret = value & ~0xf8000000;
Will post a v2 soon.
-michael
^ permalink raw reply [flat|nested] 3+ messages in thread
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2016-11-10 16:47 [PATCH] mmc: sdhci-of-esdhc: fixup PRESENT_STATE read Michael Walle
2016-11-11 13:15 ` Adrian Hunter
2016-11-11 13:25 ` Michael Walle
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