mmc: sdhci: Avoid swiotlb buffer being full

The commit de3ee99b09 ("mmc: Delete bounce buffer handling") deletes the
bounce buffer handling, but also causes the max_req_size for sdhci to be
increased, in case when max_segs == 1. This causes errors for sdhci-pci
Ricoh variant, about the swiotlb buffer to become full.

Fix the issue, by taking IO_TLB_SEGSIZE and IO_TLB_SHIFT into account when
deciding the max_req_size for sdhci.

Reported-by: Jiri Slaby <jslaby@suse.cz>
Fixes: de3ee99b09 ("mmc: Delete bounce buffer handling")
Cc: <stable@vger.kernel.org> # v4.14+
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Tested-by: Jiri Slaby <jslaby@suse.cz>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
This commit is contained in:
Ulf Hansson 2017-11-27 11:28:50 +01:00
parent 52884f8f66
commit 250dcd1146

View File

@ -21,6 +21,7 @@
#include <linux/dma-mapping.h>
#include <linux/slab.h>
#include <linux/scatterlist.h>
#include <linux/swiotlb.h>
#include <linux/regulator/consumer.h>
#include <linux/pm_runtime.h>
#include <linux/of.h>
@ -3650,17 +3651,6 @@ int sdhci_setup_host(struct sdhci_host *host)
spin_lock_init(&host->lock);
/*
* Maximum number of segments. Depends on if the hardware
* can do scatter/gather or not.
*/
if (host->flags & SDHCI_USE_ADMA)
mmc->max_segs = SDHCI_MAX_SEGS;
else if (host->flags & SDHCI_USE_SDMA)
mmc->max_segs = 1;
else /* PIO */
mmc->max_segs = SDHCI_MAX_SEGS;
/*
* Maximum number of sectors in one transfer. Limited by SDMA boundary
* size (512KiB). Note some tuning modes impose a 4MiB limit, but this
@ -3668,6 +3658,24 @@ int sdhci_setup_host(struct sdhci_host *host)
*/
mmc->max_req_size = 524288;
/*
* Maximum number of segments. Depends on if the hardware
* can do scatter/gather or not.
*/
if (host->flags & SDHCI_USE_ADMA) {
mmc->max_segs = SDHCI_MAX_SEGS;
} else if (host->flags & SDHCI_USE_SDMA) {
mmc->max_segs = 1;
if (swiotlb_max_segment()) {
unsigned int max_req_size = (1 << IO_TLB_SHIFT) *
IO_TLB_SEGSIZE;
mmc->max_req_size = min(mmc->max_req_size,
max_req_size);
}
} else { /* PIO */
mmc->max_segs = SDHCI_MAX_SEGS;
}
/*
* Maximum segment size. Could be one segment with the maximum number
* of bytes. When doing hardware scatter/gather, each entry cannot