Since the commit de3ee99b097d ("mmc: Delete bounce buffer handling") deletes the bounce buffer handling, a request data size will be referred to max_{req,seg}_size instead of MMC_QUEUE_BOUNCESZ (64k bytes). In other hand, renesas_sdhi_internal_dmac.c will set very big value of max_{req,seg}_size because the max_blk_count is set to 0xffffffff. And then, "swiotlb buffer is full" happens because swiotlb can handle a memory size up to 256k bytes only (IO_TLB_SEGSIZE = 128 and IO_TLB_SHIFT = 11). So, this patch fixes the issue to set max_blk_count to 512. Then, the max_{req,seg}_size will be set to 256k bytes. Reported-by: Dirk Behme <dirk.behme@xxxxxxxxxxxx> Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@xxxxxxxxxxx> --- drivers/mmc/host/renesas_sdhi_internal_dmac.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/mmc/host/renesas_sdhi_internal_dmac.c b/drivers/mmc/host/renesas_sdhi_internal_dmac.c index f905f23..6c9b4b2 100644 --- a/drivers/mmc/host/renesas_sdhi_internal_dmac.c +++ b/drivers/mmc/host/renesas_sdhi_internal_dmac.c @@ -80,8 +80,9 @@ .scc_offset = 0x1000, .taps = rcar_gen3_scc_taps, .taps_num = ARRAY_SIZE(rcar_gen3_scc_taps), - /* Gen3 SDHI DMAC can handle 0xffffffff blk count, but seg = 1 */ - .max_blk_count = 0xffffffff, + /* The swiotlb can handle memory size up to 256 kbytes for now. */ + .max_blk_count = 512, + /* Gen3 SDHI DMAC cannot handle scatter-gather. So, max_segs = 1 */ .max_segs = 1, }; -- 1.9.1