summaryrefslogtreecommitdiffstats
path: root/drivers/mmc/host
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/mmc/host')
-rw-r--r--drivers/mmc/host/davinci_mmc.c3
-rw-r--r--drivers/mmc/host/sdhci.c15
2 files changed, 18 insertions, 0 deletions
diff --git a/drivers/mmc/host/davinci_mmc.c b/drivers/mmc/host/davinci_mmc.c
index d7427894e0..c302eb380e 100644
--- a/drivers/mmc/host/davinci_mmc.c
+++ b/drivers/mmc/host/davinci_mmc.c
@@ -224,6 +224,9 @@ static void davinci_fifo_data_trans(struct mmc_davinci_host *host,
}
p = sgm->addr;
+ if (n > sgm->length)
+ n = sgm->length;
+
/* NOTE: we never transfer more than rw_threshold bytes
* to/from the fifo here; there's no I/O overlap.
* This also assumes that access width( i.e. ACCWD) is 4 bytes
diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index 112584aa07..fbf7a91bed 100644
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -4727,6 +4727,21 @@ int sdhci_setup_host(struct sdhci_host *host)
if (host->quirks & SDHCI_QUIRK_BROKEN_ADMA_ZEROLEN_DESC) {
host->max_adma = 65532; /* 32-bit alignment */
mmc->max_seg_size = 65535;
+ /*
+ * sdhci_adma_table_pre() expects to define 1 DMA
+ * descriptor per segment, so the maximum segment size
+ * is set accordingly. SDHCI allows up to 64KiB per DMA
+ * descriptor (16-bit field), but some controllers do
+ * not support "zero means 65536" reducing the maximum
+ * for them to 65535. That is a problem if PAGE_SIZE is
+ * 64KiB because the block layer does not support
+ * max_seg_size < PAGE_SIZE, however
+ * sdhci_adma_table_pre() has a workaround to handle
+ * that case, and split the descriptor. Refer also
+ * comment in sdhci_adma_table_pre().
+ */
+ if (mmc->max_seg_size < PAGE_SIZE)
+ mmc->max_seg_size = PAGE_SIZE;
} else {
mmc->max_seg_size = 65536;
}