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| author | Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> | 2021-08-23 11:46:18 +0100 |
|---|---|---|
| committer | Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2021-08-25 19:44:57 +0200 |
| commit | 437b38c51162f8b87beb28a833c4d5dc85fa864e (patch) | |
| tree | 2f190b8e5615010f1a5fc1cd638732e1e8e03c3b /include/acpi | |
| parent | e22ce8eb631bdc47a4a4ea7ecf4e4ba499db4f93 (diff) | |
| download | linux-437b38c51162f8b87beb28a833c4d5dc85fa864e.tar.bz2 | |
ACPI: Add memory semantics to acpi_os_map_memory()
The memory attributes attached to memory regions depend on architecture
specific mappings.
For some memory regions, the attributes specified by firmware (eg
uncached) are not sufficient to determine how a memory region should be
mapped by an OS (for instance a region that is define as uncached in
firmware can be mapped as Normal or Device memory on arm64) and
therefore the OS must be given control on how to map the region to match
the expected mapping behaviour (eg if a mapping is requested with memory
semantics, it must allow unaligned accesses).
Rework acpi_os_map_memory() and acpi_os_ioremap() back-end to split
them into two separate code paths:
acpi_os_memmap() -> memory semantics
acpi_os_ioremap() -> MMIO semantics
The split allows the architectural implementation back-ends to detect
the default memory attributes required by the mapping in question
(ie the mapping API defines the semantics memory vs MMIO) and map the
memory accordingly.
Link: https://lore.kernel.org/linux-arm-kernel/31ffe8fc-f5ee-2858-26c5-0fd8bdd68702@arm.com
Tested-by: Hanjun Guo <guohanjun@huawei.com>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: Ard Biesheuvel <ardb@kernel.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Diffstat (limited to 'include/acpi')
| -rw-r--r-- | include/acpi/acpi_io.h | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/include/acpi/acpi_io.h b/include/acpi/acpi_io.h index 027faa8883aa..a0212e67d6f4 100644 --- a/include/acpi/acpi_io.h +++ b/include/acpi/acpi_io.h @@ -14,6 +14,14 @@ static inline void __iomem *acpi_os_ioremap(acpi_physical_address phys, } #endif +#ifndef acpi_os_memmap +static inline void __iomem *acpi_os_memmap(acpi_physical_address phys, + acpi_size size) +{ + return ioremap_cache(phys, size); +} +#endif + extern bool acpi_permanent_mmap; void __iomem __ref |