On Fri, May 31, 2019 at 08:16:08PM +0900, Yoshihiro Shimoda wrote: > This patch series is based on iommu.git / next branch. > > Since SDHI host internal DMAC of the R-Car Gen3 cannot handle two or more > segments, the performance rate (especially, eMMC HS400 reading) is not good. > However, if IOMMU is enabled on the DMAC, since IOMMU will map multiple > scatter gather buffers as one contignous iova, the DMAC can handle the iova > as well and then the performance rate is possible to improve. In fact, > I have measured the performance by using bonnie++, "Sequential Input - block" > rate was improved on r8a7795. > > However, in case of a sdio card (especiialy some WiFi cards/drivers), > scatter gather buffers are possible to be not contiguous iova because > each scatter gather buffer has only about 1500 bytes, the DMAC cannot > handle it. So, this patch set adds init_card() ops to detect the card > type, and then the driver changes the max_segs if the DMAC is under > IOMMU environment and an sd card/mmc is detected. > > Changes from v3 [1]: > - Use a helper function device_iommu_mapped on patch 1 and 3. > - Check if R-Car Gen3 IPMMU is used or not on patch 3. > - Check if all multiple segment buffers are aligned to PAGE_SIZE on patch 3. > - Add Reviewed-by Wolfram-san on patch 1 and 2. Note that I also got his > Reviewed-by on patch 3, but I changed it from v2. So, I didn't add > his Reviewed-by at this time. Yes, dropping my rev on patch 3 is a good thing to do. I added Christoph to the CC list because he gave valuable input last time. @hch: If you didn't get the original mails from some list, I can bounce them to you or you can find them here: https://patchwork.kernel.org/project/linux-renesas-soc/list/?series=125593 > > Changes from v2 [2]: > - Add some conditions in the init_card(). > - Add a comment in the init_card(). > - Add definitions for some "MAX_SEGS". > > Changes from v1 [3]: > - Remove adding init_card ops into struct tmio_mmc_dma_ops and > tmio_mmc_host and just set init_card on renesas_sdhi_core.c. > - Revise typos on "mmc: tmio: No memory size limitation if runs on IOMMU". > - Add Simon-san's Reviewed-by on a tmio patch. > > [1] > https://patchwork.kernel.org/project/linux-renesas-soc/list/?series=120985 > > [2] > https://patchwork.kernel.org/project/linux-renesas-soc/list/?series=116729 > > [3] > https://patchwork.kernel.org/project/linux-renesas-soc/list/?series=110485 > > > Yoshihiro Shimoda (3): > mmc: tmio: No memory size limitation if runs on IOMMU > mmc: tmio: Add a definition for default max_segs > mmc: renesas_sdhi: use multiple segments if possible > > drivers/mmc/host/renesas_sdhi.h | 1 + > drivers/mmc/host/renesas_sdhi_core.c | 60 +++++++++++++++++++++++++++ > drivers/mmc/host/renesas_sdhi_internal_dmac.c | 19 +++++++++ > drivers/mmc/host/tmio_mmc.h | 1 + > drivers/mmc/host/tmio_mmc_core.c | 7 ++-- > 5 files changed, 85 insertions(+), 3 deletions(-) > > -- > 2.7.4 >
Attachment:
signature.asc
Description: PGP signature
