From: Neil Armstrong narmstrong@baylibre.com
commit 8a38a4d51c5055d0201542e5ea3c0cb287f6e223 upstream.
The memory at the end of the controller only accepts 32bit read/write accesses, but the arm64 memcpy_to/fromio implementation only uses 64bit (which will be split into two 32bit access) and 8bit leading to incomplete copies to/from this memory when the buffer is not multiple of 8bytes.
Add a local copy using writel/readl accesses to make sure we use the right memory access width.
The switch to memcpy_to/fromio was done because of 285133040e6c ("arm64: Import latest memcpy()/memmove() implementation"), but using memcpy worked before since it mainly used 32bit memory acceses.
Fixes: 103a5348c22c ("mmc: meson-gx: use memcpy_to/fromio for dram-access-quirk") Reported-by: Christian Hewitt christianshewitt@gmail.com Suggested-by: Martin Blumenstingl martin.blumenstingl@googlemail.com Signed-off-by: Neil Armstrong narmstrong@baylibre.com Tested-by: Martin Blumenstingl martin.blumenstingl@googlemail.com Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20210928073652.434690-1-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 | 73 ++++++++++++++++++++++++++++++++-------- 1 file changed, 59 insertions(+), 14 deletions(-)
--- a/drivers/mmc/host/meson-gx-mmc.c +++ b/drivers/mmc/host/meson-gx-mmc.c @@ -738,7 +738,7 @@ static void meson_mmc_desc_chain_transfe writel(start, host->regs + SD_EMMC_START); }
-/* local sg copy to buffer version with _to/fromio usage for dram_access_quirk */ +/* local sg copy for dram_access_quirk */ static void meson_mmc_copy_buffer(struct meson_host *host, struct mmc_data *data, size_t buflen, bool to_buffer) { @@ -756,21 +756,27 @@ static void meson_mmc_copy_buffer(struct sg_miter_start(&miter, sgl, nents, sg_flags);
while ((offset < buflen) && sg_miter_next(&miter)) { - unsigned int len; + unsigned int buf_offset = 0; + unsigned int len, left; + u32 *buf = miter.addr;
len = min(miter.length, buflen - offset); + left = len;
- /* 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); + if (to_buffer) { + do { + writel(*buf++, host->bounce_iomem_buf + offset + buf_offset); + + buf_offset += 4; + left -= 4; + } while (left); } else { - if (to_buffer) - memcpy(host->bounce_buf + offset, miter.addr, len); - else - memcpy(miter.addr, host->bounce_buf + offset, len); + do { + *buf++ = readl(host->bounce_iomem_buf + offset + buf_offset); + + buf_offset += 4; + left -= 4; + } while (left); }
offset += len; @@ -822,7 +828,11 @@ static void meson_mmc_start_cmd(struct m if (data->flags & MMC_DATA_WRITE) { cmd_cfg |= CMD_CFG_DATA_WR; WARN_ON(xfer_bytes > host->bounce_buf_size); - meson_mmc_copy_buffer(host, data, xfer_bytes, true); + if (host->dram_access_quirk) + meson_mmc_copy_buffer(host, data, xfer_bytes, true); + else + sg_copy_to_buffer(data->sg, data->sg_len, + host->bounce_buf, xfer_bytes); dma_wmb(); }
@@ -841,12 +851,43 @@ static void meson_mmc_start_cmd(struct m writel(cmd->arg, host->regs + SD_EMMC_CMD_ARG); }
+static int meson_mmc_validate_dram_access(struct mmc_host *mmc, struct mmc_data *data) +{ + struct scatterlist *sg; + int i; + + /* Reject request if any element offset or size is not 32bit aligned */ + for_each_sg(data->sg, sg, data->sg_len, i) { + if (!IS_ALIGNED(sg->offset, sizeof(u32)) || + !IS_ALIGNED(sg->length, sizeof(u32))) { + dev_err(mmc_dev(mmc), "unaligned sg offset %u len %u\n", + data->sg->offset, data->sg->length); + return -EINVAL; + } + } + + return 0; +} + static void meson_mmc_request(struct mmc_host *mmc, struct mmc_request *mrq) { struct meson_host *host = mmc_priv(mmc); bool needs_pre_post_req = mrq->data && !(mrq->data->host_cookie & SD_EMMC_PRE_REQ_DONE);
+ /* + * The memory at the end of the controller used as bounce buffer for + * the dram_access_quirk only accepts 32bit read/write access, + * check the aligment and length of the data before starting the request. + */ + if (host->dram_access_quirk && mrq->data) { + mrq->cmd->error = meson_mmc_validate_dram_access(mmc, mrq->data); + if (mrq->cmd->error) { + mmc_request_done(mmc, mrq); + return; + } + } + if (needs_pre_post_req) { meson_mmc_get_transfer_mode(mmc, mrq); if (!meson_mmc_desc_chain_mode(mrq->data)) @@ -991,7 +1032,11 @@ static irqreturn_t meson_mmc_irq_thread( if (meson_mmc_bounce_buf_read(data)) { xfer_bytes = data->blksz * data->blocks; WARN_ON(xfer_bytes > host->bounce_buf_size); - meson_mmc_copy_buffer(host, data, xfer_bytes, false); + if (host->dram_access_quirk) + meson_mmc_copy_buffer(host, data, xfer_bytes, false); + else + sg_copy_from_buffer(data->sg, data->sg_len, + host->bounce_buf, xfer_bytes); }
next_cmd = meson_mmc_get_next_command(cmd);