On Fri, May 5, 2017 at 2:37 PM, Rob Clark <robdclark@xxxxxxxxx> wrote: > On Fri, May 5, 2017 at 3:04 PM, Rob Herring <robh@xxxxxxxxxx> wrote: >> On Fri, May 5, 2017 at 1:21 PM, Rob Clark <robdclark@xxxxxxxxx> wrote: >>> An iommu driver for Qualcomm "B" family devices which do not completely >>> implement the ARM SMMU spec. These devices have context-bank register >>> layout that is similar to ARM SMMU, but no global register space (or at >>> least not one that is accessible). >>> >>> Signed-off-by: Rob Clark <robdclark@xxxxxxxxx> >>> --- >>> v1: original >>> v2: bindings cleanups and kconfig issues that kbuild robot pointed out >>> v4: fix issues pointed out by Rob H. and actually make device removal >>> work >>> v3: fix WARN_ON() splats reported by Archit >>> >>> drivers/iommu/Kconfig | 9 + >>> drivers/iommu/Makefile | 1 + >>> drivers/iommu/qcom_iommu.c | 833 +++++++++++++++++++++++++++++++++++++++++++++ >>> 3 files changed, 843 insertions(+) >>> create mode 100644 drivers/iommu/qcom_iommu.c >>> >>> diff --git a/drivers/iommu/Kconfig b/drivers/iommu/Kconfig >>> index 37e204f..f8f79a4 100644 >>> --- a/drivers/iommu/Kconfig >>> +++ b/drivers/iommu/Kconfig >>> @@ -359,4 +359,13 @@ config MTK_IOMMU_V1 >>> >>> if unsure, say N here. >>> >>> +config QCOM_IOMMU >>> + bool "Qualcomm IOMMU Support" >> >> Either this needs to be tristate or... >> >> [...] >>> +#include <linux/module.h> >> >> this include and the things that need it should go. Or some >> explanation like "once X happens, then we can enable as module" and >> leave it all for now. > > tbh, I'm not sure what the issue is for modules (other than > potentially that you'd want the iommu driver fairly early in boot if > you didn't have an initrd). I just saw that the other iommu drivers > are all bool. (Sorry, I don't really follow iommu-devel so not > familiar with the history.) With my distro hat on, I would prefer > them to be modules eventually. For starters, does it even build as a module if you allow that? It might not work because of some run-time ordering, but that's good enough for this discussion. > >> See this[1] for some background. > > it mentions there are some downsides, but I can't see where those > downsides are listed ;-) > > I would kinda prefer to leave the MODULE_*() stuff in place unless > modular iommu drivers are never going to happen. Maybe a note, so the module police don't fix it. Rob -- To unsubscribe from this list: send the line "unsubscribe linux-arm-msm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
