From 27a5e7d36d383970affae801d77141deafd536a8 Mon Sep 17 00:00:00 2001 From: Neil Armstrong Date: Mon, 8 Jun 2020 10:44:58 +0200 Subject: mmc: meson-gx: limit segments to 1 when dram-access-quirk is needed The actual max_segs computation leads to failure while using the broadcom sdio brcmfmac/bcmsdh driver, since the driver tries to make usage of scatter gather. But with the dram-access-quirk we use a 1,5K SRAM bounce buffer, and the max_segs current value of 3 leads to max transfers to 4,5k, which doesn't work. This patch sets max_segs to 1 to better describe the hardware limitation, and fix the SDIO functionality with the brcmfmac/bcmsdh driver on Amlogic G12A/G12B SoCs on boards like SEI510 or Khadas VIM3. Reported-by: Art Nikpal Reported-by: Christian Hewitt Fixes: acdc8e71d9bb ("mmc: meson-gx: add dram-access-quirk") Signed-off-by: Neil Armstrong Reviewed-by: Kevin Hilman Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20200608084458.32014-1-narmstrong@baylibre.com Signed-off-by: Ulf Hansson --- drivers/mmc/host/meson-gx-mmc.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) (limited to 'drivers/mmc/host') diff --git a/drivers/mmc/host/meson-gx-mmc.c b/drivers/mmc/host/meson-gx-mmc.c index 7eb38d7482c6..08a3b1c05acb 100644 --- a/drivers/mmc/host/meson-gx-mmc.c +++ b/drivers/mmc/host/meson-gx-mmc.c @@ -1146,9 +1146,11 @@ static int meson_mmc_probe(struct platform_device *pdev) mmc->caps |= MMC_CAP_CMD23; if (host->dram_access_quirk) { + /* Limit segments to 1 due to low available sram memory */ + mmc->max_segs = 1; /* Limit to the available sram memory */ - mmc->max_segs = SD_EMMC_SRAM_DATA_BUF_LEN / mmc->max_blk_size; - mmc->max_blk_count = mmc->max_segs; + mmc->max_blk_count = SD_EMMC_SRAM_DATA_BUF_LEN / + mmc->max_blk_size; } else { mmc->max_blk_count = CMD_CFG_LENGTH_MASK; mmc->max_segs = SD_EMMC_DESC_BUF_LEN / -- cgit v1.2.3