| From 27a5e7d36d383970affae801d77141deafd536a8 Mon Sep 17 00:00:00 2001 |
| From: Neil Armstrong <narmstrong@baylibre.com> |
| Date: Mon, 8 Jun 2020 10:44:58 +0200 |
| Subject: mmc: meson-gx: limit segments to 1 when dram-access-quirk is needed |
| |
| From: Neil Armstrong <narmstrong@baylibre.com> |
| |
| commit 27a5e7d36d383970affae801d77141deafd536a8 upstream. |
| |
| 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 <art@khadas.com> |
| Reported-by: Christian Hewitt <christianshewitt@gmail.com> |
| Fixes: acdc8e71d9bb ("mmc: meson-gx: add dram-access-quirk") |
| Signed-off-by: Neil Armstrong <narmstrong@baylibre.com> |
| Reviewed-by: Kevin Hilman <khilman@baylibre.com> |
| Cc: stable@vger.kernel.org |
| Link: https://lore.kernel.org/r/20200608084458.32014-1-narmstrong@baylibre.com |
| Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| |
| --- |
| drivers/mmc/host/meson-gx-mmc.c | 6 ++++-- |
| 1 file changed, 4 insertions(+), 2 deletions(-) |
| |
| --- a/drivers/mmc/host/meson-gx-mmc.c |
| +++ b/drivers/mmc/host/meson-gx-mmc.c |
| @@ -1151,9 +1151,11 @@ static int meson_mmc_probe(struct platfo |
| |
| 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 / |