On Fri, Nov 15, 2019 at 02:44:30PM +0100, Eugeniu Rosca wrote:
> Isolated initially to renesas_sdhi_internal_dmac [1], Ulf suggested
> adding MMC_CAP_ERASE to the TMIO mmc core:
> 
> On Fri, Nov 15, 2019 at 10:27:25AM +0100, Ulf Hansson wrote:
>  -- snip --
>  This test and due to the discussions with Wolfram and you in this
>  thread, I would actually suggest that you enable MMC_CAP_ERASE for all
>  tmio variants, rather than just for this particular one.
> 
>  In other words, set the cap in tmio_mmc_host_probe() should be fine,
>  as it seems none of the tmio variants supports HW busy detection at
>  this point.
>  -- snip --
> 
> Testing on R-Car H3ULCB-KF doesn't reveal any issues (v5.4-rc7):
> 
> root@rcar-gen3:~# lsblk
> NAME         MAJ:MIN RM  SIZE RO TYPE MOUNTPOINT
> mmcblk0      179:0    0 59.2G  0 disk  <--- eMMC
> mmcblk0boot0 179:8    0    4M  1 disk
> mmcblk0boot1 179:16   0    4M  1 disk
> mmcblk1      179:24   0   30G  0 disk  <--- SD card
> 
> root@rcar-gen3:~# time blkdiscard /dev/mmcblk0
> real    0m8.659s
> user    0m0.001s
> sys     0m1.920s
> 
> root@rcar-gen3:~# time blkdiscard /dev/mmcblk1
> real    0m1.176s
> user    0m0.001s
> sys     0m0.124s
> 
> [1] https://lore.kernel.org/linux-renesas-soc/20191112134808.23546-1-erosca@de.adit-jv.com/
> 
> Cc: Wolfram Sang <wsa+renesas@sang-engineering.com>
> Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
> Cc: Andrew Gabbasov <andrew_gabbasov@mentor.com>
> Originally-by: Harish Jenny K N <harish_kandiga@mentor.com>
> Suggested-by: Ulf Hansson <ulf.hansson@linaro.org>
> Signed-off-by: Eugeniu Rosca <erosca@de.adit-jv.com>

Reviewed-by: Wolfram Sang <wsa+renesas@sang-engineering.com>