iommu/arm-smmu-v3: Don't reserve implementation defined register space

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Some SMMUv3 implementation embed the Perf Monitor Group Registers (PMCG)
inside the first 64kB region of the SMMU. Since PMCG are managed by a
separate driver, this layout causes resource reservation conflicts
during boot.

To avoid this conflict, don't reserve the MMIO regions that are
implementation defined. Although devm_ioremap_resource() still works on
full pages under the hood, this way we benefit from resource conflict
checks.

Fixes: 7d839b4b9e ("perf/smmuv3: Add arm64 smmuv3 pmu driver")
Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/20200513110255.597203-1-jean-philippe@linaro.org
Signed-off-by: Will Deacon <will@kernel.org>

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Jean-Philippe Brucker 2020-05-13 13:02:57 +02:00 • committed by Will Deacon

parent d100ff3843

commit 52f3fab006

1 changed files with 31 additions and 4 deletions

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drivers/iommu/arm-smmu-v3.c

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