On Mon, Aug 23, 2021 at 11:46:18AM +0100, Lorenzo Pieralisi wrote: > 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@xxxxxxx > Tested-by: Hanjun Guo <guohanjun@xxxxxxxxxx> > Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@xxxxxxx> > Acked-by: Ard Biesheuvel <ardb@xxxxxxxxxx> > Cc: Ard Biesheuvel <ardb@xxxxxxxxxx> > Cc: Will Deacon <will@xxxxxxxxxx> > Cc: Hanjun Guo <guohanjun@xxxxxxxxxx> > Cc: Sudeep Holla <sudeep.holla@xxxxxxx> > Cc: Catalin Marinas <catalin.marinas@xxxxxxx> > Cc: "Rafael J. Wysocki" <rjw@xxxxxxxxxxxxx> > --- > Resending with all lists CC'ed. > > Patch series is a v3 of a previous version[2]: > > v2->v3: > - Dropped first two-patches following LKML feedback[2] > v1->v2 > - Added patch 1 and 2 according to feedback received on[1] > > [1] https://lore.kernel.org/linux-acpi/20210726100026.12538-1-lorenzo.pieralisi@xxxxxxx > [2] https://lore.kernel.org/linux-acpi/20210802152359.12623-1-lorenzo.pieralisi@xxxxxxx > > arch/arm64/include/asm/acpi.h | 3 +++ > arch/arm64/kernel/acpi.c | 19 ++++++++++++++++--- > drivers/acpi/osl.c | 23 ++++++++++++++++------- > include/acpi/acpi_io.h | 8 ++++++++ > 4 files changed, 43 insertions(+), 10 deletions(-) For arm64: Acked-by: Catalin Marinas <catalin.marinas@xxxxxxx> I presume this patch would go in via the acpi tree. -- Catalin
