RE: [PATCH] mmc: dw_mmc: Add hardware lock error (HLE) to the CMD error flag

[Seungwon Jeon <tgih.jun@samsung.com>]

On Fri, November 15, 2013, Jaehoon Chung wrote:
> Dear, Alim,
> 
> Well, I'm not sure that this patch is correct.
> But as you mentioned, we need to decide how control the HLE.
> 
> I will check the HLE on this weekend. Thanks for your effort.

Thank you for remind.
HLE should be cleared at least although it needs to be handled more properly.
I agree on that now.

Your patch is below?
https://patchwork.kernel.org/patch/2981661/

I think it's simple and good way.
It would be better to add error message when happened.

Thanks,
Seungwon Jeon

> 
> Best Regards,
> Jaehoon Chung
> 
> On 11/12/2013 01:12 PM, Alim Akhtar wrote:
> > Hi Seungwon/ Jaehoon,
> > I can see there are at least three patches which address HLE (Hardware
> > Lock Error) in dw_mmc driver.
> >
> > https://patchwork.kernel.org/patch/1814991/
> > http://www.spinics.net/lists/linux-mmc/msg21459.html
> > and third one is my patch
> > http://news.gmane.org/gmane.linux.kernel.mmc/cutoff=23010
> >
> > Can we have some conclusion about how to handle HLE?
> >
> > Thanks!!!
> >
> > On Thu, Oct 10, 2013 at 4:31 PM, Alim Akhtar <alim.akhtar@gmail.com> wrote:
> >> Hi Jaeohoon,
> >>
> >> On Mon, Oct 7, 2013 at 2:00 AM, ALIM AKHTAR <alim.akhtar@samsung.com> wrote:
> >>> Hi Jaeohoon,
> >>> Thanks for quick review.
> >>>> ------- Original Message -------
> >>>> Sender : Jaehoon Chung<jh80.chung@samsung.com> S4/Engineer/System S/W Lab./Samsung Electronics
> >>>> Date : Oct 07, 2013 17:36 (GMT+09:00)
> >>>> Title : Re: [PATCH] mmc: dw_mmc: Add hardware lock error (HLE) to the CMD error flag
> >>>
> >>>> Hi, Alim.
> >>>
> >>>> On 10/07/2013 05:21 PM, ALIM AKHTAR wrote:
> >>>>>
> >>>>>
> >>>>>> ------- Original Message -------
> >>>>>> Sender : Jaehoon Chung S4/Engineer/System S/W Lab./Samsung Electronics
> >>>>>> Date : Oct 07, 2013 13:34 (GMT+09:00)
> >>>>>> Title : Re: [PATCH] mmc: dw_mmc: Add hardware lock error (HLE) to the CMD error flag
> >>>>>
> >>>>>> On 10/07/2013 01:22 PM, ALIM AKHTAR wrote:
> >>>>>>> Hi Jaehoon,
> >>>>>>>
> >>>>>>>> ------- Original Message -------
> >>>>>>>> Sender : Jaehoon Chung S4/Engineer/System S/W Lab./Samsung Electronics
> >>>>>>>> Date : Oct 06, 2013 17:28 (GMT+09:00)
> >>>>>>> Title : Re: [PATCH] mmc: dw_mmc: Add hardware lock error (HLE) to the CMD error flag
> >>>>>>
> >>>>>>> Hi Alim,
> >>>>>>
> >>>>>>> On 10/03/2013 06:18 PM, alim akhtar wrote:
> >>>>>>>> From: Alim Akhtar
> >>>>>>>>
> >>>>>>>> Hardware locked error set when the dw_mmc controller cannot load a
> >>>>>>>> command issued by software. When software sets the start_cmd bit in the
> >>>>>>>> CMD register, the controller tries to load the command. If the command
> >>>>>>>> buffer is already filled with a command, this error is raised. Currently
> >>>>>>>> driver does not handle HLE interrupt, which results in a system hang.
> >>>>>>> When SDMMC_INT_HLE is set into CMD_ERROR_FLAGS,.then could driver handle the HLE interrupt?
> >>>>>> Yes, this will be handled as a part of DW_MCI_CMD_ERROR_FLAGS error handling.
> >>>>>> Could some command or data be lost?
> >>>>> No, Data and command will not be lost as they are not send out.
> >>>> Maybe it needs to discuss how recovery the command/data, when HLE interrupt is occured.
> >>>> I want to know, do you have the recovery method when HLE interrupt is occured?
> >>>>
> >>>> As you mentioned, this patch controlled the HLE error and can't send the any command/data.
> >>>> Patch like this had already posted at mailing list.
> >>> Can you point to the link?
> >>>> But we also need to control after occurred the HLE.
> >>> Well, dw_mmc controller document just say "The software then has to reload the command" to recover
> from HLE.
> >>>> In SD-card's case, card can be inserted/removed. but in case of eMMC, can't it.
> >>>> It should be maintained the hardware lock status.
> >>> HLE is independent of emmc/sd slot and handling should be the same.
> >>> Insert/removal is one way to simulate HLE, this is how I found this.
> >>> Are you suggesting to check for INT_STATUE for emmc and handle it in case of HLE?
> >>
> >> Let me know if you have any other comments/ suggestions on this.
> >> Thanks!!
> >>
> >>>>> Best Regards,
> >>>>> Jaehoon Chung
> >>>
> >>>>>>>
> >>>>>>>> Best Regards,
> >>>>>>>> Jaehoon Chung
> >>>>>>>>
> >>>>>>>> HLE can be simulated by quickly inserting and removing sd card in card
> >>>>>>>> slot (30 ~ 40 times in say 20 secs)
> >>>>>>>>
> >>>>>>>> Reviewed-by: Doug Anderson
> >>>>>>>> Signed-off-by: Alim Akhtar
> >>>>>>>> ---
> >>>>>>>>   drivers/mmc/host/dw_mmc.c | 2 +-
> >>>>>>>>   1 file changed, 1 insertion(+), 1 deletion(-)
> >>>>>>>>
> >>>>>>>> diff --git a/drivers/mmc/host/dw_mmc.c b/drivers/mmc/host/dw_mmc.c
> >>>>>>>> index 0a6a512..24b4a52 100644
> >>>>>>>> --- a/drivers/mmc/host/dw_mmc.c
> >>>>>>>> +++ b/drivers/mmc/host/dw_mmc.c
> >>>>>>>> @@ -44,7 +44,7 @@
> >>>>>>>>   SDMMC_INT_HTO | SDMMC_INT_SBE  | \
> >>>>>>>>   SDMMC_INT_EBE)
> >>>>>>>>   #define DW_MCI_CMD_ERROR_FLAGS (SDMMC_INT_RTO | SDMMC_INT_RCRC | \
> >>>>>>>> - SDMMC_INT_RESP_ERR)
> >>>>>>>> + SDMMC_INT_RESP_ERR | SDMMC_INT_HLE)
> >>>>>>>>   #define DW_MCI_ERROR_FLAGS (DW_MCI_DATA_ERROR_FLAGS | \
> >>>>>>>>   DW_MCI_CMD_ERROR_FLAGS  | SDMMC_INT_HLE)
> >>>>>>>>   #define DW_MCI_SEND_STATUS 1
> >>
> >> --
> >> Regards,
> >> Alim
> >
> >
> >
> 
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