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. > 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. BR, -R > Rob > > [1] https://lwn.net/Articles/643854/ -- 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
