diff options
author | Neil Armstrong <narmstrong@baylibre.com> | 2021-06-09 17:02:30 +0200 |
---|---|---|
committer | Ulf Hansson <ulf.hansson@linaro.org> | 2021-06-14 14:02:33 +0200 |
commit | 103a5348c22c3fca8b96c735a9e353b8a0801842 (patch) | |
tree | 1d422098b4cfdc485c7ffb4f17e07bb7201d8fcc /drivers/mmc | |
parent | 009c9aa5be652675a06d5211e1640e02bbb1c33d (diff) | |
download | linux-103a5348c22c3fca8b96c735a9e353b8a0801842.tar.bz2 |
mmc: meson-gx: use memcpy_to/fromio for dram-access-quirk
It has been reported that usage of memcpy() to/from an iomem mapping is invalid,
and a recent arm64 memcpy update [1] triggers a memory abort when dram-access-quirk
is used on the G12A/G12B platforms.
This adds a local sg_copy_to_buffer which makes usage of io versions of memcpy
when dram-access-quirk is enabled.
[1] 285133040e6c ("arm64: Import latest memcpy()/memmove() implementation")
Fixes: acdc8e71d9bb ("mmc: meson-gx: add dram-access-quirk")
Reported-by: Marek Szyprowski <m.szyprowski@samsung.com>
Suggested-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Link: https://lore.kernel.org/r/20210609150230.9291-1-narmstrong@baylibre.com
Cc: stable@vger.kernel.org
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Diffstat (limited to 'drivers/mmc')
-rw-r--r-- | drivers/mmc/host/meson-gx-mmc.c | 50 |
1 files changed, 45 insertions, 5 deletions
diff --git a/drivers/mmc/host/meson-gx-mmc.c b/drivers/mmc/host/meson-gx-mmc.c index 016a6106151a..3f28eb4d17fe 100644 --- a/drivers/mmc/host/meson-gx-mmc.c +++ b/drivers/mmc/host/meson-gx-mmc.c @@ -165,6 +165,7 @@ struct meson_host { unsigned int bounce_buf_size; void *bounce_buf; + void __iomem *bounce_iomem_buf; dma_addr_t bounce_dma_addr; struct sd_emmc_desc *descs; dma_addr_t descs_dma_addr; @@ -745,6 +746,47 @@ static void meson_mmc_desc_chain_transfer(struct mmc_host *mmc, u32 cmd_cfg) writel(start, host->regs + SD_EMMC_START); } +/* local sg copy to buffer version with _to/fromio usage for dram_access_quirk */ +static void meson_mmc_copy_buffer(struct meson_host *host, struct mmc_data *data, + size_t buflen, bool to_buffer) +{ + unsigned int sg_flags = SG_MITER_ATOMIC; + struct scatterlist *sgl = data->sg; + unsigned int nents = data->sg_len; + struct sg_mapping_iter miter; + unsigned int offset = 0; + + if (to_buffer) + sg_flags |= SG_MITER_FROM_SG; + else + sg_flags |= SG_MITER_TO_SG; + + sg_miter_start(&miter, sgl, nents, sg_flags); + + while ((offset < buflen) && sg_miter_next(&miter)) { + unsigned int len; + + len = min(miter.length, buflen - offset); + + /* When dram_access_quirk, the bounce buffer is a iomem mapping */ + if (host->dram_access_quirk) { + if (to_buffer) + memcpy_toio(host->bounce_iomem_buf + offset, miter.addr, len); + else + memcpy_fromio(miter.addr, host->bounce_iomem_buf + offset, len); + } else { + if (to_buffer) + memcpy(host->bounce_buf + offset, miter.addr, len); + else + memcpy(miter.addr, host->bounce_buf + offset, len); + } + + offset += len; + } + + sg_miter_stop(&miter); +} + static void meson_mmc_start_cmd(struct mmc_host *mmc, struct mmc_command *cmd) { struct meson_host *host = mmc_priv(mmc); @@ -788,8 +830,7 @@ static void meson_mmc_start_cmd(struct mmc_host *mmc, struct mmc_command *cmd) if (data->flags & MMC_DATA_WRITE) { cmd_cfg |= CMD_CFG_DATA_WR; WARN_ON(xfer_bytes > host->bounce_buf_size); - sg_copy_to_buffer(data->sg, data->sg_len, - host->bounce_buf, xfer_bytes); + meson_mmc_copy_buffer(host, data, xfer_bytes, true); dma_wmb(); } @@ -958,8 +999,7 @@ static irqreturn_t meson_mmc_irq_thread(int irq, void *dev_id) if (meson_mmc_bounce_buf_read(data)) { xfer_bytes = data->blksz * data->blocks; WARN_ON(xfer_bytes > host->bounce_buf_size); - sg_copy_from_buffer(data->sg, data->sg_len, - host->bounce_buf, xfer_bytes); + meson_mmc_copy_buffer(host, data, xfer_bytes, false); } next_cmd = meson_mmc_get_next_command(cmd); @@ -1179,7 +1219,7 @@ static int meson_mmc_probe(struct platform_device *pdev) * instead of the DDR memory */ host->bounce_buf_size = SD_EMMC_SRAM_DATA_BUF_LEN; - host->bounce_buf = host->regs + SD_EMMC_SRAM_DATA_BUF_OFF; + host->bounce_iomem_buf = host->regs + SD_EMMC_SRAM_DATA_BUF_OFF; host->bounce_dma_addr = res->start + SD_EMMC_SRAM_DATA_BUF_OFF; } else { /* data bounce buffer */ |