Subject: Re: [PATCH] mmc: dw_mmc-rockchip: fix failing to mount partition with
 "discard"
To: Jaehoon Chung <jh80.chung@samsung.com>
References: <1456816373-32518-1-git-send-email-shawn.lin@rock-chips.com>
 <56D641FA.8010606@samsung.com> <56EAD13D.8050400@rock-chips.com>
 <56EB5E3F.7010701@samsung.com>
Cc: shawn.lin@rock-chips.com, Ulf Hansson <ulf.hansson@linaro.org>,
        linux-rockchip@lists.infradead.org, linux-mmc@vger.kernel.org,
        linux-kernel@vger.kernel.org
From: Shawn Lin <shawn.lin@rock-chips.com>
Message-ID: <56EB880F.1040606@rock-chips.com>
Date: Fri, 18 Mar 2016 12:46:07 +0800
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Hi Jaehoon,

On 2016-3-18 9:47, Jaehoon Chung wrote:
> Hi Shawn,
>
> On 03/18/2016 12:46 AM, Shawn Lin wrote:
>> Hi jaehoon,
>>
>> On 2016/3/2 9:29, Jaehoon Chung wrote:
>>> Hi Shawn.
>>>
>>> On 03/01/2016 04:12 PM, Shawn Lin wrote:
>>>> Without MMC_CAP_ERASE support, we fail to mount partition
>>>> with "discard" option since mmc_queue_setup_discard is limited
>>>> for checking mmc_can_erase. Without doing mmc_queue_setup_discard,
>>>> blk_queue_discard fails to test QUEUE_FLAG_DISCARD flag, so we get
>>>> the following log from f2fs(actually similar to other file system):
>>>>
>>>> mounting with "discard" option, but the device does not support discard
>>>
>>> We can enable MMC_CAP_ERASE by default, since other SoC also needs this capability.
>>> I had sent some patch for enabling by default, but at that time i didn't remember why not enabled by default.
>>> I will check that reason..and share the information.
>>>
>>
>> Any good news? :)
>> Or let add it for dw_mmc by default?
>
> Sorry for replying too late..I had other tasks..:(
> Today or Tomorrow, i will apply the patches related with dw-mmcc controller.
> And will request to pull to Ulf.
>
> I didn't check...but i think this patch will be applied on dw_mmc-rockchip.
> After then..we can use it by default in future.
>

Thanks. That's a good plan.

> Refer to below.
> https://patchwork.kernel.org/patch/4240491/

yes, I also found this patch and it was not merge yet.
So we still need MMC_CAP_ERASE to make sure we can enable
discard unless the cap is removed in future.


>
> Best Regards,
> Jaehoon Chung
>
>>
>>> Best Regards,
>>> Jaehoon Chung
>>>
>>>>
>>>> Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com>
>>>> ---
>>>>
>>>>    drivers/mmc/host/dw_mmc-rockchip.c | 9 +++++++++
>>>>    1 file changed, 9 insertions(+)
>>>>
>>>> diff --git a/drivers/mmc/host/dw_mmc-rockchip.c b/drivers/mmc/host/dw_mmc-rockchip.c
>>>> index 84e50f3..2eda118 100644
>>>> --- a/drivers/mmc/host/dw_mmc-rockchip.c
>>>> +++ b/drivers/mmc/host/dw_mmc-rockchip.c
>>>> @@ -234,11 +234,20 @@ static int dw_mci_rockchip_init(struct dw_mci *host)
>>>>        return 0;
>>>>    }
>>>>
>>>> +/* Common capabilities of RK3288 SoC */
>>>> +static unsigned long dw_mci_rk3288_dwmmc_caps[4] = {
>>>> +    MMC_CAP_ERASE,
>>>> +    MMC_CAP_ERASE,
>>>> +    MMC_CAP_ERASE,
>>>> +    MMC_CAP_ERASE,
>>>> +};
>>>> +
>>>>    static const struct dw_mci_drv_data rk2928_drv_data = {
>>>>        .init            = dw_mci_rockchip_init,
>>>>    };
>>>>
>>>>    static const struct dw_mci_drv_data rk3288_drv_data = {
>>>> +    .caps            = dw_mci_rk3288_dwmmc_caps,
>>>>        .set_ios        = dw_mci_rk3288_set_ios,
>>>>        .execute_tuning        = dw_mci_rk3288_execute_tuning,
>>>>        .parse_dt        = dw_mci_rk3288_parse_dt,
>>>>
>>>
>>>
>>> _______________________________________________
>>> Linux-rockchip mailing list
>>> Linux-rockchip@lists.infradead.org
>>> http://lists.infradead.org/mailman/listinfo/linux-rockchip
>>>
>>
>>
>
>
>
>