| Message ID | 20241020142931.138277-1-aurelien@aurel32.net |
|---|---|
| State | New |
| Headers | show |
| Series | mmc: dw_mmc: take SWIOTLB memory size limitation into account | expand |
Hi Aurelien, On Sun, 20 Oct 2024 at 20:01, Aurelien Jarno <aurelien@aurel32.net> wrote: > > The Synopsys DesignWare mmc controller on the JH7110 SoC > (dw_mmc-starfive.c driver) is using a 32-bit IDMAC address bus width, > and thus requires the use of SWIOTLB. > > The commit 8396c793ffdf ("mmc: dw_mmc: Fix IDMAC operation with pages > bigger than 4K") increased the max_seq_size, even for 4K pages, causing > "swiotlb buffer is full" to happen because swiotlb can only handle a > memory size up to 256kB only. > > Fix the issue, by making sure the dw_mmc driver doesn't use segments > bigger than what SWIOTLB can handle. > > Reported-by: Ron Economos <re@w6rz.net> > Reported-by: Jing Luo <jing@jing.rocks> > Fixes: 8396c793ffdf ("mmc: dw_mmc: Fix IDMAC operation with pages bigger than 4K") > Cc: stable@vger.kernel.org > Signed-off-by: Aurelien Jarno <aurelien@aurel32.net> > --- Please add my Tested-by: Anand Moon <linux.amoon@gmail.com> Thanks for fixing the warning below. [ 511.837216][ T148] dwmmc_starfive 16020000.mmc: swiotlb buffer is full (sz: 290816 bytes), total 65536 (slots), used 246 (slots) [ 511.837423][ C0] dwmmc_starfive 16020000.mmc: swiotlb buffer is full (sz: 278528 bytes), total 65536 (slots), used 222 (slots) [ 511.916951][ C0] dwmmc_starfive 16020000.mmc: swiotlb buffer is full (sz: 290816 bytes), total 65536 (slots), used 24 (slots) [ 516.803916][ T575] dwmmc_starfive 16020000.mmc: swiotlb buffer is full (sz: 507904 bytes), total 65536 (slots), used 122 (slots) [ 516.805450][ C0] dwmmc_starfive 16020000.mmc: swiotlb buffer is full (sz: 507904 bytes), total 65536 (slots), used 364 (slots) Thanks -Anand > drivers/mmc/host/dw_mmc.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/drivers/mmc/host/dw_mmc.c b/drivers/mmc/host/dw_mmc.c > index 41e451235f637..dc0d6201f7b73 100644 > --- a/drivers/mmc/host/dw_mmc.c > +++ b/drivers/mmc/host/dw_mmc.c > @@ -2958,7 +2958,8 @@ static int dw_mci_init_slot(struct dw_mci *host) > mmc->max_segs = host->ring_size; > mmc->max_blk_size = 65535; > mmc->max_req_size = DW_MCI_DESC_DATA_LENGTH * host->ring_size; > - mmc->max_seg_size = mmc->max_req_size; > + mmc->max_seg_size = > + min_t(size_t, mmc->max_req_size, dma_max_mapping_size(host->dev)); > mmc->max_blk_count = mmc->max_req_size / 512; > } else if (host->use_dma == TRANS_MODE_EDMAC) { > mmc->max_segs = 64; > -- > 2.45.2 > > > _______________________________________________ > linux-riscv mailing list > linux-riscv@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/linux-riscv
On 2024-10-20 23:29, Aurelien Jarno wrote: > The Synopsys DesignWare mmc controller on the JH7110 SoC > (dw_mmc-starfive.c driver) is using a 32-bit IDMAC address bus width, > and thus requires the use of SWIOTLB. > > The commit 8396c793ffdf ("mmc: dw_mmc: Fix IDMAC operation with pages > bigger than 4K") increased the max_seq_size, even for 4K pages, causing > "swiotlb buffer is full" to happen because swiotlb can only handle a > memory size up to 256kB only. > > Fix the issue, by making sure the dw_mmc driver doesn't use segments > bigger than what SWIOTLB can handle. > > Reported-by: Ron Economos <re@w6rz.net> > Reported-by: Jing Luo <jing@jing.rocks> > Fixes: 8396c793ffdf ("mmc: dw_mmc: Fix IDMAC operation with pages > bigger than 4K") > Cc: stable@vger.kernel.org > Signed-off-by: Aurelien Jarno <aurelien@aurel32.net> Feel free to add: Tested-by: Jing Luo <jing@jing.rocks> This patch not only fixes the kernel log spam by dwmmc_starfive reporting "swiotlb buffer is full", but also seems to have fixed a serious bug that causes data corruption on emmc (as I reported to Debian [1]), which at least can be observed on both Visionfive 2 and Star64 boards. To add a cherry on the top, with this patch applied, I see massive performance improvement (sequential rw speed) on emmc: with a quick-and-dirty test using `dd bs=1M`, on Visionfive 2, it goes from 28MB/s to 42MB/s (+50%); on Star64, it goes from 13MB/s to 46MB/s (+253%). [1] https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1085425 Thanks & cheers, Jing Luo > --- > drivers/mmc/host/dw_mmc.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/drivers/mmc/host/dw_mmc.c b/drivers/mmc/host/dw_mmc.c > index 41e451235f637..dc0d6201f7b73 100644 > --- a/drivers/mmc/host/dw_mmc.c > +++ b/drivers/mmc/host/dw_mmc.c > @@ -2958,7 +2958,8 @@ static int dw_mci_init_slot(struct dw_mci *host) > mmc->max_segs = host->ring_size; > mmc->max_blk_size = 65535; > mmc->max_req_size = DW_MCI_DESC_DATA_LENGTH * host->ring_size; > - mmc->max_seg_size = mmc->max_req_size; > + mmc->max_seg_size = > + min_t(size_t, mmc->max_req_size, > dma_max_mapping_size(host->dev)); > mmc->max_blk_count = mmc->max_req_size / 512; > } else if (host->use_dma == TRANS_MODE_EDMAC) { > mmc->max_segs = 64;
diff --git a/drivers/mmc/host/dw_mmc.c b/drivers/mmc/host/dw_mmc.c index 41e451235f637..dc0d6201f7b73 100644 --- a/drivers/mmc/host/dw_mmc.c +++ b/drivers/mmc/host/dw_mmc.c @@ -2958,7 +2958,8 @@ static int dw_mci_init_slot(struct dw_mci *host) mmc->max_segs = host->ring_size; mmc->max_blk_size = 65535; mmc->max_req_size = DW_MCI_DESC_DATA_LENGTH * host->ring_size; - mmc->max_seg_size = mmc->max_req_size; + mmc->max_seg_size = + min_t(size_t, mmc->max_req_size, dma_max_mapping_size(host->dev)); mmc->max_blk_count = mmc->max_req_size / 512; } else if (host->use_dma == TRANS_MODE_EDMAC) { mmc->max_segs = 64;
The Synopsys DesignWare mmc controller on the JH7110 SoC (dw_mmc-starfive.c driver) is using a 32-bit IDMAC address bus width, and thus requires the use of SWIOTLB. The commit 8396c793ffdf ("mmc: dw_mmc: Fix IDMAC operation with pages bigger than 4K") increased the max_seq_size, even for 4K pages, causing "swiotlb buffer is full" to happen because swiotlb can only handle a memory size up to 256kB only. Fix the issue, by making sure the dw_mmc driver doesn't use segments bigger than what SWIOTLB can handle. Reported-by: Ron Economos <re@w6rz.net> Reported-by: Jing Luo <jing@jing.rocks> Fixes: 8396c793ffdf ("mmc: dw_mmc: Fix IDMAC operation with pages bigger than 4K") Cc: stable@vger.kernel.org Signed-off-by: Aurelien Jarno <aurelien@aurel32.net> --- drivers/mmc/host/dw_mmc.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)