From: Thierry Reding <tred...@nvidia.com>
The MSM IOMMU driver unconditionally calls bus_set_iommu(), which is a
very stupid thing to do on multi-platform kernels. While marking the
driver BROKEN may seem a little extreme, there is no other way to make
the driver skip initialization. One of the problems is that it doesn't
have devicetree binding documentation and the driver doesn't contain a
struct of_device_id table either, so no way to check that it is indeed
valid to set up the IOMMU operations for this driver.
This fixes a problem on Tegra20 where the DRM driver will try to use the
obviously non-existent MSM IOMMU.
Marking the driver BROKEN shouldn't do any harm, since there aren't any
users currently. There is no struct of_device_id table, so the device
can't be instantiated from device tree, and I couldn't find any code
that would instantiate a matching platform_device either, so the driver
is effectively unused.
Reported-by: Nicolas Chauvet <kwiz...@gmail.com>
Cc: David Brown <dav...@codeaurora.org>
Cc: Daniel Walker <dwal...@fifo99.com>
Cc: Bryan Huntsman <bry...@codeaurora.org>
Cc: Olav Haugan <ohau...@codeaurora.org>
Signed-off-by: Thierry Reding <tred...@nvidia.com>
---
drivers/iommu/Kconfig | 1 +
1 file changed, 1 insertion(+)
diff --git a/drivers/iommu/Kconfig b/drivers/iommu/Kconfig
index 325188eef1c1..0f70bc1fce65 100644
--- a/drivers/iommu/Kconfig
+++ b/drivers/iommu/Kconfig
@@ -31,6 +31,7 @@ config FSL_PAMU
config MSM_IOMMU
bool "MSM IOMMU Support"
depends on ARCH_MSM8X60 || ARCH_MSM8960
+ depends on BROKEN
select IOMMU_API
help
Support for the IOMMUs found on certain Qualcomm SOCs.
--
2.1.3
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