This patch series is based on linux-next.git / next-20190828 tag. 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.
To achieve this, this patch series modifies IOMMU and Block subsystem at first. This patch series is strictly depended on each subsystem modification, so that I submit it as treewide. Changes from v9: - Rebase on next-20190828. - Drop a blk-setting.c patch to sort headers. - Remove an unnecessary condition on patch 2/4. - Add Joerg-san's Reviewed-by into patch 2/4. - Fix a condition on patch 4/4 not to call blk_queue_max_segment_size() as the comment. https://patchwork.kernel.org/project/linux-renesas-soc/list/?series=151067 Changes from v8: - Rebase on next-20190726. - Use "1UL" instead of just "1" for iommu_dma_get_merge_boundary(). - Add Simon-san's Reviewed-by into all patches. https://patchwork.kernel.org/project/linux-renesas-soc/list/?series=149023 Changes from v7: - Rebase on next-20190722 (v5.3-rc1 + next branches of subsystems) - Add some Reviewed-by. https://patchwork.kernel.org/project/linux-renesas-soc/list/?series=135391 Changes from v6: - [1/5 for DMA MAP] A new patch. - [2/5 for IOMMU] A new patch. - [3/5 for BLOCK] Add Reviewed-by. - [4/5 for BLOCK] Use a new DMA MAP API instead of device_iommu_mapped(). - [5/5 for MMC] Likewise, and some minor fix. - Remove patch 4/5 of v6 from this v7 patch series. https://patchwork.kernel.org/project/linux-renesas-soc/list/?series=131769 Changes from v5: - Almost all patches are new code. - [4/5 for MMC] This is a refactor patch so that I don't add any {Tested,Reviewed}-by tags. - [5/5 for MMC] Modify MMC subsystem to use bigger segments instead of the renesas_sdhi driver. - [5/5 for MMC] Use BLK_MAX_SEGMENTS (128) instead of local value SDHI_MAX_SEGS_IN_IOMMU (512). Even if we use BLK_MAX_SEGMENTS, the performance is still good. https://patchwork.kernel.org/project/linux-renesas-soc/list/?series=127511 Changes from v4: - [DMA MAPPING] Add a new device_dma_parameters for iova contiguous. - [IOMMU] Add a new capable for "merging" segments. - [IOMMU] Add a capable ops into the ipmmu-vmsa driver. - [MMC] Sort headers in renesas_sdhi_core.c. - [MMC] Remove the following codes that made on v3 that can be achieved by DMA MAPPING and IOMMU subsystem: -- 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. https://patchwork.kernel.org/project/linux-renesas-soc/list/?series=125593 Changes from v3: - 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. Yoshihiro Shimoda (4): dma: Introduce dma_get_merge_boundary() iommu/dma: Add a new dma_map_ops of get_merge_boundary() block: add a helper function to merge the segments mmc: queue: Use bigger segments if DMA MAP layer can merge the segments Documentation/DMA-API.txt | 8 ++++++++ block/blk-settings.c | 23 +++++++++++++++++++++++ drivers/iommu/dma-iommu.c | 8 ++++++++ drivers/mmc/core/queue.c | 35 ++++++++++++++++++++++++++++++++--- include/linux/blkdev.h | 2 ++ include/linux/dma-mapping.h | 6 ++++++ include/linux/mmc/host.h | 1 + kernel/dma/mapping.c | 11 +++++++++++ 8 files changed, 91 insertions(+), 3 deletions(-) -- 2.7.4
