RE: [PATCH 1/1] dw_mmc: insmod followed by rmmod will hung for eMMC

From: Prabu Thangamuthu
Date: Wed May 27 2015 - 01:15:28 EST


Hi Ulf, Jaehoon,

Thanks for your comments, I will update and send a new Patch.

> On 05/27/2015 7:20 AM, Jaehoon Chung Wrote:
>
> Hi, Pradu.
>
> Sorry for late.
No Problem.
> I will wait for your next version than i will check yours.
> To Ulf.
>
> Thanks for review!
>
> Best Regards,
> Jaehoon Chung
>
> On 05/22/2015 10:21 PM, Ulf Hansson wrote:
> > On 18 May 2015 at 16:23, Prabu Thangamuthu <Prabu.T@xxxxxxxxxxxx>
> wrote:
> >> Removing dw_mmc driver immediately after inserting the dw_mmc driver
> >> is
> >
> > I guess it hangs even if you remove it after a couple of days? :-)
> >
> > Perhaps makes this a bit more clear?
> >
> >> getting hung for eMMC device. Root cause for this issue is,
> >> dw_mci_remove will disable all the interrupts then it will call
> dw_mci_cleanup_slot.
> >> dw_mci_cleanup_slot is issuing CMD6 to disable boot partition access
> >> and it's waiting for command complete interrupt. Since INTMASK was
> >> already cleared by dw_mci_remove, command complete interrupt is not
> >> reaching the system. This leads to process hung.
> >
> > /s dw_mci_remove / dw_mci_remove()
> >
> >>
> >> Signed-off-by: Prabu Thangamuthu <prabu.t@xxxxxxxxxxxx>
> >
> > This patch looks good overall, but please send a new version with
> > updated changelog. Moreover, please use "mmc: dw_mmc:" as prefix for
> > the commit message header.
> >
> > Kind regards
> > Uffe
> >
> >> ---
> >> drivers/mmc/host/dw_mmc.c | 6 +++---
> >> 1 files changed, 3 insertions(+), 3 deletions(-)
> >>
> >> diff --git a/drivers/mmc/host/dw_mmc.c b/drivers/mmc/host/dw_mmc.c
> >> index 5f5adaf..f0a0aff 100644
> >> --- a/drivers/mmc/host/dw_mmc.c
> >> +++ b/drivers/mmc/host/dw_mmc.c
> >> @@ -2941,15 +2941,15 @@ void dw_mci_remove(struct dw_mci *host) {
> >> int i;
> >>
> >> - mci_writel(host, RINTSTS, 0xFFFFFFFF);
> >> - mci_writel(host, INTMASK, 0); /* disable all mmc interrupt first */
> >> -
> >> for (i = 0; i < host->num_slots; i++) {
> >> dev_dbg(host->dev, "remove slot %d\n", i);
> >> if (host->slot[i])
> >> dw_mci_cleanup_slot(host->slot[i], i);
> >> }
> >>
> >> + mci_writel(host, RINTSTS, 0xFFFFFFFF);
> >> + mci_writel(host, INTMASK, 0); /* disable all mmc interrupt
> >> + first */
> >> +
> >> /* disable clock to CIU */
> >> mci_writel(host, CLKENA, 0);
> >> mci_writel(host, CLKSRC, 0);
> >> --
> >> 1.7.6.5
> >

Thanks & Regards,
Prabu Thangamuthu.