mmc: sdio: Fix sdio wait busy implement limitation
diff mbox

Message ID 1492416571-28843-2-git-send-email-jiajie.hao@mediatek.com
State New
Headers show

Commit Message

jiajie.hao@mediatek.com April 17, 2017, 8:09 a.m. UTC
From: Jiajie Hao <jiajie.hao@mediatek.com>

The host may issue an I/O abort by writing to the CCCR at any time
during I/O read operation via CMD52. And host may need suspend
transcation during write busy stage in SDIO suspend/resume scenario.
From other side, a card may accept CMD52 during data transfer phase.

Previous implement would block issuing above command in busy stage.
It cause function driver can't implement as proper way and has no
opportunity to do some coverage in error case via I/O abort etc.

We need bypass some necessary operation during busy check stage.

Change-Id: Ib5a4599a2a98cbcf441b564f5f6fbb10c8a59e1b
Signed-off-by: Jiajie Hao <jiajie.hao@mediatek.com>
---
 drivers/mmc/core/core.c     |    4 +++-
 drivers/mmc/core/sdio_ops.h |   10 ++++++++++
 2 files changed, 13 insertions(+), 1 deletion(-)

Comments

Ulf Hansson April 20, 2017, 1:27 p.m. UTC | #1
On 17 April 2017 at 10:09,  <jiajie.hao@mediatek.com> wrote:
> From: Jiajie Hao <jiajie.hao@mediatek.com>
>
> The host may issue an I/O abort by writing to the CCCR at any time
> during I/O read operation via CMD52. And host may need suspend
> transcation during write busy stage in SDIO suspend/resume scenario.
> From other side, a card may accept CMD52 during data transfer phase.
>
> Previous implement would block issuing above command in busy stage.
> It cause function driver can't implement as proper way and has no
> opportunity to do some coverage in error case via I/O abort etc.
>
> We need bypass some necessary operation during busy check stage.
>
> Change-Id: Ib5a4599a2a98cbcf441b564f5f6fbb10c8a59e1b

Please remove this.

> Signed-off-by: Jiajie Hao <jiajie.hao@mediatek.com>
> ---
>  drivers/mmc/core/core.c     |    4 +++-
>  drivers/mmc/core/sdio_ops.h |   10 ++++++++++
>  2 files changed, 13 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c
> index 926e0fd..9c9a4bc 100644
> --- a/drivers/mmc/core/core.c
> +++ b/drivers/mmc/core/core.c
> @@ -234,8 +234,10 @@ static void __mmc_start_request(struct mmc_host *host, struct mmc_request *mrq)
>         /*
>          * For sdio rw commands we must wait for card busy otherwise some
>          * sdio devices won't work properly.
> +        * And bypass I/O abort, reset and bus suspend operations.
>          */
> -       if (mmc_is_io_op(mrq->cmd->opcode) && host->ops->card_busy) {
> +       if (mmc_is_io_op(mrq->cmd->opcode) && host->ops->card_busy &&
> +           !mmc_is_io_bypass(mrq->cmd->opcode, mrq->cmd->arg)) {

Instead of adding yet another function, let's extend the existing
mmc_is_io_op() to cover this new cases as well.

Moreover, to be reflect the purpose of the function, I suggest we
rename it from mmc_is_io_op() to sdio_is_op_busy().

>                 int tries = 500; /* Wait aprox 500ms at maximum */
>
>                 while (host->ops->card_busy(host) && --tries)
> diff --git a/drivers/mmc/core/sdio_ops.h b/drivers/mmc/core/sdio_ops.h
> index bed8a83..9896696 100644
> --- a/drivers/mmc/core/sdio_ops.h
> +++ b/drivers/mmc/core/sdio_ops.h
> @@ -31,5 +31,15 @@ static inline bool mmc_is_io_op(u32 opcode)
>         return opcode == SD_IO_RW_DIRECT || opcode == SD_IO_RW_EXTENDED;
>  }
>
> +static inline bool mmc_is_io_bypass(u32 opcode, u32 arg)
> +{
> +       u32 addr;
> +
> +       addr = (arg >> 9) & 0x1FFFF;
> +
> +       return ((opcode == SD_IO_RW_DIRECT) &&
> +               (addr == SDIO_CCCR_ABORT || addr == SDIO_CCCR_SUSPEND));
> +}
> +
>  #endif
>
> --
> 1.7.9.5
>

Kind regards
Uffe
jiajie.hao@mediatek.com April 23, 2017, 6:42 a.m. UTC | #2
Hi Ulf,

Very appreciated for your comment.
> On Thu, 2017-04-20 at 15:27 +0200, Ulf Hansson wrote:
> On 17 April 2017 at 10:09,  <jiajie.hao@mediatek.com> wrote:
> > From: Jiajie Hao <jiajie.hao@mediatek.com>
> >
> > The host may issue an I/O abort by writing to the CCCR at any time
> > during I/O read operation via CMD52. And host may need suspend
> > transcation during write busy stage in SDIO suspend/resume scenario.
> > From other side, a card may accept CMD52 during data transfer phase.
> >
> > Previous implement would block issuing above command in busy stage.
> > It cause function driver can't implement as proper way and has no
> > opportunity to do some coverage in error case via I/O abort etc.
> >
> > We need bypass some necessary operation during busy check stage.
> >
> > Change-Id: Ib5a4599a2a98cbcf441b564f5f6fbb10c8a59e1b
> 
> Please remove this.
OK.
> > Signed-off-by: Jiajie Hao <jiajie.hao@mediatek.com>
> > ---
> >  drivers/mmc/core/core.c     |    4 +++-
> >  drivers/mmc/core/sdio_ops.h |   10 ++++++++++
> >  2 files changed, 13 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c
> > index 926e0fd..9c9a4bc 100644
> > --- a/drivers/mmc/core/core.c
> > +++ b/drivers/mmc/core/core.c
> > @@ -234,8 +234,10 @@ static void __mmc_start_request(struct mmc_host *host, struct mmc_request *mrq)
> >         /*
> >          * For sdio rw commands we must wait for card busy otherwise some
> >          * sdio devices won't work properly.
> > +        * And bypass I/O abort, reset and bus suspend operations.
> >          */
> > -       if (mmc_is_io_op(mrq->cmd->opcode) && host->ops->card_busy) {
> > +       if (mmc_is_io_op(mrq->cmd->opcode) && host->ops->card_busy &&
> > +           !mmc_is_io_bypass(mrq->cmd->opcode, mrq->cmd->arg)) {
> 
> Instead of adding yet another function, let's extend the existing
> mmc_is_io_op() to cover this new cases as well.
> 
> Moreover, to be reflect the purpose of the function, I suggest we
> rename it from mmc_is_io_op() to sdio_is_op_busy().
It's a good suggestion. I'll resend patch in v2 for review.
> >                 int tries = 500; /* Wait aprox 500ms at maximum */
> >
> >                 while (host->ops->card_busy(host) && --tries)
> > diff --git a/drivers/mmc/core/sdio_ops.h b/drivers/mmc/core/sdio_ops.h
> > index bed8a83..9896696 100644
> > --- a/drivers/mmc/core/sdio_ops.h
> > +++ b/drivers/mmc/core/sdio_ops.h
> > @@ -31,5 +31,15 @@ static inline bool mmc_is_io_op(u32 opcode)
> >         return opcode == SD_IO_RW_DIRECT || opcode == SD_IO_RW_EXTENDED;
> >  }
> >
> > +static inline bool mmc_is_io_bypass(u32 opcode, u32 arg)
> > +{
> > +       u32 addr;
> > +
> > +       addr = (arg >> 9) & 0x1FFFF;
> > +
> > +       return ((opcode == SD_IO_RW_DIRECT) &&
> > +               (addr == SDIO_CCCR_ABORT || addr == SDIO_CCCR_SUSPEND));
> > +}
> > +
> >  #endif
> >
> > --
> > 1.7.9.5
> >
> 
> Kind regards
> Uffe

Best regards
Jiajie

Patch
diff mbox

diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c
index 926e0fd..9c9a4bc 100644
--- a/drivers/mmc/core/core.c
+++ b/drivers/mmc/core/core.c
@@ -234,8 +234,10 @@  static void __mmc_start_request(struct mmc_host *host, struct mmc_request *mrq)
 	/*
 	 * For sdio rw commands we must wait for card busy otherwise some
 	 * sdio devices won't work properly.
+	 * And bypass I/O abort, reset and bus suspend operations.
 	 */
-	if (mmc_is_io_op(mrq->cmd->opcode) && host->ops->card_busy) {
+	if (mmc_is_io_op(mrq->cmd->opcode) && host->ops->card_busy &&
+	    !mmc_is_io_bypass(mrq->cmd->opcode, mrq->cmd->arg)) {
 		int tries = 500; /* Wait aprox 500ms at maximum */
 
 		while (host->ops->card_busy(host) && --tries)
diff --git a/drivers/mmc/core/sdio_ops.h b/drivers/mmc/core/sdio_ops.h
index bed8a83..9896696 100644
--- a/drivers/mmc/core/sdio_ops.h
+++ b/drivers/mmc/core/sdio_ops.h
@@ -31,5 +31,15 @@  static inline bool mmc_is_io_op(u32 opcode)
 	return opcode == SD_IO_RW_DIRECT || opcode == SD_IO_RW_EXTENDED;
 }
 
+static inline bool mmc_is_io_bypass(u32 opcode, u32 arg)
+{
+	u32 addr;
+
+	addr = (arg >> 9) & 0x1FFFF;
+
+	return ((opcode == SD_IO_RW_DIRECT) &&
+		(addr == SDIO_CCCR_ABORT || addr == SDIO_CCCR_SUSPEND));
+}
+
 #endif