Re: [PATCH RFC 3/5] mmc: mmci: relax blksz check for SDIO

From: Srinivas Kandagatla
Date: Wed Aug 13 2014 - 01:14:58 EST

Thankyou for the feedback.

On 12/08/14 15:12, Russell King - ARM Linux wrote:
On Tue, Aug 12, 2014 at 01:04:40PM +0100, Srinivas Kandagatla wrote:
From: Srinivas Kandagatla <srinivas.kandagatla@xxxxxxxxxx>

This patch adds condition in mmci_validate_data to skip checking
blocksize for SDIO card types. SDIO card type can issue blocksizes
which are not exactly power of 2 so this check always fails, resulting
in SDIO failures.

Do you understand why this check is there?

Do you realise that the standard MMCI from ARM Ltd can /only/ perform
power-of-2 block transfers?

Yes, I noticed that in pl180 TRM. I agree this patch will break standard MMCI.

In the past Ulf Hansson and Stefan Nilsson have submitted a patch to fix this issue for ux500v2. This patch adds new flag non_power_of_2_blksize / any_blksize to variant_data.

This patch will fix the issue for Qcom too. If you are Ok with adding new flag non_power_of_2_blksize/any_blksize in the variant_data, I can rebase and include Ulf's patch in next version.


Hence, NAK on this change as it stands.

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