On Mon, Jul 26, 2021 at 05:55:33PM +0200, Ard Biesheuvel wrote: > On Mon, 26 Jul 2021 at 12:00, Lorenzo Pieralisi > <lorenzo.pieralisi@xxxxxxx> 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 > > Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@xxxxxxx> > > 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> > > For the patch in general > > Acked-by: Ard Biesheuvel <ardb@xxxxxxxxxx> Thanks ! [...] > > -void __iomem __ref > > -*acpi_os_map_iomem(acpi_physical_address phys, acpi_size size) > > +static void __iomem __ref > > +*__acpi_os_map_iomem(acpi_physical_address phys, acpi_size size, bool memory) > > { > > struct acpi_ioremap *map; > > void __iomem *virt; > > @@ -353,7 +356,7 @@ void __iomem __ref > > > > pg_off = round_down(phys, PAGE_SIZE); > > pg_sz = round_up(phys + size, PAGE_SIZE) - pg_off; > > - virt = acpi_map(phys, size); > > + virt = acpi_map(phys, size, memory); > > if (!virt) { > > mutex_unlock(&acpi_ioremap_lock); > > kfree(map); > > @@ -372,11 +375,17 @@ void __iomem __ref > > mutex_unlock(&acpi_ioremap_lock); > > return map->virt + (phys - map->phys); > > } > > + > > +void __iomem __ref > > +*acpi_os_map_iomem(acpi_physical_address phys, acpi_size size) > > I am aware that this just duplicated the prototype above, but I think > this should be > > void __iomem *__ref > > given that the __ref comes after the * in the prototype below. Yes I just moved/duplicated the prototype above but I believe this is consistent with include/acpi/acpi_io.h unless I have not understood what you meant ? It is probably worth changing it in both places to void __iomem *__ref ? I can do that with an additional patch. > > > +{ > > + return __acpi_os_map_iomem(phys, size, false); > > +} > > EXPORT_SYMBOL_GPL(acpi_os_map_iomem); > > > > void *__ref acpi_os_map_memory(acpi_physical_address phys, acpi_size size) > > { > > - return (void *)acpi_os_map_iomem(phys, size); > > + return (void *)__acpi_os_map_iomem(phys, size, true); > > I think this should be (__force void *) to shut up sparse address > space warnings. Yes I can add that attribute in an additional patch and rebase this one on top of it. Thanks, Lorenzo > > > } > > EXPORT_SYMBOL_GPL(acpi_os_map_memory); > > > > 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 > > -- > > 2.31.0 > >
