Re: [PATCH v4 2/3] mmc: host: sdhci: Add request_done ops for struct sdhci_ops

From: Baolin Wang
Date: Mon Oct 28 2019 - 04:38:34 EST


On Mon, 28 Oct 2019 at 16:27, Baolin Wang <baolin.wang@xxxxxxxxxx> wrote:
>
> Hi Adrian,
>
> On Mon, 28 Oct 2019 at 16:20, Adrian Hunter <adrian.hunter@xxxxxxxxx> wrote:
> >
> > On 22/10/19 8:58 AM, Baolin Wang wrote:
> > > Add request_done ops for struct sdhci_ops as a preparation in case some
> > > host controllers have different method to complete one request, such as
> > > supporting request completion of MMC software queue.
> > >
> > > Signed-off-by: Baolin Wang <baolin.wang@xxxxxxxxxx>
> > > ---
> > > drivers/mmc/host/sdhci.c | 12 ++++++++++--
> > > drivers/mmc/host/sdhci.h | 2 ++
> > > 2 files changed, 12 insertions(+), 2 deletions(-)
> > >
> > > diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
> > > index b056400..850241f 100644
> > > --- a/drivers/mmc/host/sdhci.c
> > > +++ b/drivers/mmc/host/sdhci.c
> > > @@ -2729,7 +2729,10 @@ static bool sdhci_request_done(struct sdhci_host *host)
> > >
> > > spin_unlock_irqrestore(&host->lock, flags);
> > >
> > > - mmc_request_done(host->mmc, mrq);
> > > + if (host->ops->request_done)
> > > + host->ops->request_done(host, mrq);
> >
> > For hsq, couldn't this result in sdhci_request() being called interrupt
> > context here.
>
> Right, now it did not support.
>
> >
> > To prevent that you would need to add a condition to sdhci_defer_done() so
> > it always defers when using hsq.
>
> Yes, but now the condition can be matched in sdhci_defer_done() when
> using hsq. So no need to worry that the sdhci_request() will be called
> in interrupt
> context in this patch set. Thanks.
>

Wait, sorry, I realized some drivers may not select the
SDHCI_REQ_USE_DMA flag in sdhci_defer_done() when using hsq. OK, So
how about below changes?

diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index 850241f..6c7a396 100644
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -3035,7 +3035,7 @@ static inline bool sdhci_defer_done(struct
sdhci_host *host,
{
struct mmc_data *data = mrq->data;

- return host->pending_reset ||
+ return IS_ENABLED(CONFIG_MMC_HSQ) || host->pending_reset ||
((host->flags & SDHCI_REQ_USE_DMA) && data &&
data->host_cookie == COOKIE_MAPPED);
}

--
Baolin Wang
Best Regards