Re: [PATCH 2/2] mmc: meson-gx: also check SD_IO_RW_EXTENDED for scatterlist size alignment
From: Ulf Hansson <hidden>
Date: 2021-05-11 10:56:59
Also in:
linux-amlogic, linux-mmc, lkml
On Mon, 26 Apr 2021 at 19:56, Neil Armstrong [off-list ref] wrote:
The brcmfmac driver can generate a scatterlist from a skb with each packets
not aligned to the block size. This is not supported by the Amlogic Descriptor
dma engine where each descriptor must match a multiple of the block size.
The sg list is valid, since the sum of the sg buffers is a multiple of the
block size, but we must discard those when in SD_IO_RW_EXTENDED mode since
SDIO block mode can be used under the hood even with data->blocks == 1.
Those transfers are very rare, thus can be replaced by a bounce buffer
without real performance loss.
Fixes: 7412dee9f1fd ("mmc: meson-gx: replace WARN_ONCE with dev_warn_once about scatterlist size alignment in block mode")
Reported-by: Christian Hewitt <redacted>
Signed-off-by: Neil Armstrong <redacted>Applied for fixes and by adding a stable tag, thanks! Kind regards Uffe
quoted hunk ↗ jump to hunk
--- drivers/mmc/host/meson-gx-mmc.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)diff --git a/drivers/mmc/host/meson-gx-mmc.c b/drivers/mmc/host/meson-gx-mmc.c index 1c61f0f24c09..016a6106151a 100644 --- a/drivers/mmc/host/meson-gx-mmc.c +++ b/drivers/mmc/host/meson-gx-mmc.c@@ -236,7 +236,8 @@ static void meson_mmc_get_transfer_mode(struct mmc_host *mmc, if (host->dram_access_quirk) return; - if (data->blocks > 1) { + /* SD_IO_RW_EXTENDED (CMD53) can also use block mode under the hood */ + if (data->blocks > 1 || mrq->cmd->opcode == SD_IO_RW_EXTENDED) { /* * In block mode DMA descriptor format, "length" field indicates * number of blocks and there is no way to pass DMA size that --2.25.1
_______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel