Re: [RFC PATCH 0/2] mmc: sdhci: Add SDHCI_QUIRK2_BROKEN_SDMA_BOUNDARY_BUFFER

From: Srinivas Kandagatla
Date: Wed Jun 28 2017 - 14:16:30 EST




On 28/06/17 18:21, Ritesh Harjani wrote:
Hi Srinivas,

On 6/28/2017 7:05 PM, srinivas.kandagatla@xxxxxxxxxx wrote:
From: Srinivas Kandagatla <srinivas.kandagatla@xxxxxxxxxx>

This patchset adds quirk to support cards which have issues when sdma
boundary buffer bits are programmed in Block Size Register (0x04)
when using ADMA.

Thanks for pointing out the reason of failure without this patch.
Earlier I could not find the reason.

Previous discussion link :-
https://patchwork.kernel.org/patch/9200579/

I did see this patch, only issue I had is making it default.




First patch adds quirk and second one uses that quirk in msm sdhci driver.

Not sure if quirk will be the right way to go about this, or whether we should make this functionality default since ADMA does not
uses this (as per spec) ?
Since other systems should not break (as Adrian was mentioning in the discussion link above).

That was the only reason to add this as quirk, so that other drivers would work as it previously.

Also, this seems to be a issue with only qcom controller, so quirk makes more sense for me.

Adrian/Ulf will know better on this.


--srini

Tested on DB410c with WLAN SDIO card.

thanks,
srini

Srinivas Kandagatla (2):
mmc: sdhci: add quirk SDHCI_QUIRK2_BROKEN_SDMA_BOUNDARY_BUFFER
mmc: sdhci-msm: enable SDHCI_QUIRK2_BROKEN_SDMA_BOUNDARY_BUFFER

drivers/mmc/host/sdhci-msm.c | 3 ++-
drivers/mmc/host/sdhci.c | 24 ++++++++++++++++++------
drivers/mmc/host/sdhci.h | 2 ++
3 files changed, 22 insertions(+), 7 deletions(-)