Commit 250dcd11 authored by Ulf Hansson's avatar Ulf Hansson
Browse files

mmc: sdhci: Avoid swiotlb buffer being full 



The commit de3ee99b ("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: default avatarJiri Slaby <jslaby@suse.cz>
Fixes: de3ee99b ("mmc: Delete bounce buffer handling")
Cc: <stable@vger.kernel.org> # v4.14+
Signed-off-by: default avatarUlf Hansson <ulf.hansson@linaro.org>
Tested-by: default avatarJiri Slaby <jslaby@suse.cz>
Acked-by: default avatarAdrian Hunter <adrian.hunter@intel.com>
parent 52884f8f

drivers/mmc/host/sdhci.c

+18 −10
Original line number Diff line number Diff line
@@ -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>
@@ -3650,23 +3651,30 @@ int sdhci_setup_host(struct sdhci_host *host) 


	spin_lock_init(&host->lock);



	/*

	 * Maximum number of sectors in one transfer. Limited by SDMA boundary

	 * size (512KiB). Note some tuning modes impose a 4MiB limit, but this

	 * is less anyway.

	 */

	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)

	if (host->flags & SDHCI_USE_ADMA) {

		mmc->max_segs = SDHCI_MAX_SEGS;

	else if (host->flags & SDHCI_USE_SDMA)

	} else if (host->flags & SDHCI_USE_SDMA) {

		mmc->max_segs = 1;

	else /* PIO */

		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 number of sectors in one transfer. Limited by SDMA boundary

	 * size (512KiB). Note some tuning modes impose a 4MiB limit, but this

	 * is less anyway.

	 */

	mmc->max_req_size = 524288;

	}



	/*

	 * Maximum segment size. Could be one segment with the maximum number

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