Dear Eiraku-san, Here's a couple of patches that rework your IPMMU driver in the direction pointed to by my comments. Feel free to use them as a base, squash them into your code (my name doesn't need to be kept in commit messages) or even ignore them completely where they make no sense.
Patch 5/14 has been sent to the linux-arm-kernel mailing list already as it's an independent fix (but required by the next patches in the series). After these 14 patches I ran into the issue of matching devices with a particular IPMMU instance. This turned out to be more complex than I initially thought. There's currently no driver in mainline that performs that task, and I'm not sure whether the core infrastructure allows for doing so without resorting to hacks. The problem has been discussed very recently on the iommu list, you can find more information at http://patchwork.ozlabs.org/patch/203717/. No solution has been agreed on so far, maybe you could reply to the mail thread. Feel free to CC me. I'm unsure whether we should use a single ARM IOMMU mapping or one mapping per device. This needs to be investigated as there's little documentation on the subject. I would advice contacting Marek Szyprowski (the author of the ARM DMA IOMMU code) to discuss this matter. Once again feel free to CC me, as well as the appropriate mailing lists. In my opinion the shmobile_iommu_attach_all_devices() function should be removed, and devices should be attached with an IOMMU either as they are added to the system, or as they are probed. Bus notifiers might be usable to achieve that, as implemented in the above Tegra SMMU patch. This requires the IOMMU being registered and fully operational at attachment time, so explicit IOMMU attachment in driver code might be a better solution for now. That would likely require one ARM DMA IOMMU mapping per device, device drivers would explicitly call arm_iommu_create_mapping() and arm_iommu_attach_device(). Laurent Pinchart (14): ARM: sh-mobile: Protect ipmmu.h header with ifndef/define shmobile-iommu: Move IPMMU driver to drivers/iommu shmobile-iommu: Remove __devinit shmobile-iommu: Use devm_* managed functions ARM: iommu: Include linux/kref.h in asm/dma-iommu.h shmobile-iommu: Sort header files alphabetically shmobile-iommu: Move header file from arch/ to drivers/iommu/ shmobile-iommu: Rename shmobile_iommu_priv to shmobile_iommu_domain shmobile-ipmmu: Rename ipmmu_priv to shmobile_ipmmu shmobile-ipmmu: Pass a struct shmobile_ipmmu to IPMMU functions shmobile-ipmmu: Store a struct shmobile_iommu_arch_data in archdata.iommu shmobile-ipmmu: Store ipmmu pointer in iommu arch data and iommu domain shmobile-ipmmu: Remove unneeded lock_add spinlock shmobile-ipmmu: Store iommu_mapping in struct shmobile_ipmmu arch/arm/include/asm/dma-iommu.h | 1 + arch/arm/mach-shmobile/Kconfig | 6 - arch/arm/mach-shmobile/Makefile | 3 - arch/arm/mach-shmobile/board-ap4evb.c | 2 +- arch/arm/mach-shmobile/board-mackerel.c | 2 +- arch/arm/mach-shmobile/include/mach/ipmmu.h | 16 -- arch/arm/mach-shmobile/setup-sh7372.c | 2 +- drivers/iommu/Kconfig | 6 + drivers/iommu/Makefile | 1 + drivers/iommu/shmobile-iommu.c | 259 +++++++++++--------- .../ipmmu.c => drivers/iommu/shmobile-ipmmu.c | 107 ++++----- drivers/iommu/shmobile-ipmmu.h | 27 ++ include/linux/sh_iommu.h | 20 ++ 13 files changed, 248 insertions(+), 204 deletions(-) delete mode 100644 arch/arm/mach-shmobile/include/mach/ipmmu.h rename arch/arm/mach-shmobile/ipmmu.c => drivers/iommu/shmobile-ipmmu.c (51%) create mode 100644 drivers/iommu/shmobile-ipmmu.h create mode 100644 include/linux/sh_iommu.h -- Regards, Laurent Pinchart -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
