Hi Heinrich,
[...]
> > > +++ b/arch/arm/lib/cache.c
> > > @@ -170,3 +170,5 @@ __weak int arm_reserve_mmu(void)
> > >
> > > return 0;
> > > }
> > > +
> > > +void __weak pgprot_set_attrs(phys_addr_t addr, size_t size, u64 perm) {}
> >
> > I would prefer if the weak function would return -ENOSYS indicating the
> > missing implementation and the real function would return 0 in case of
> > success or an error code on failure. This way the EFI protocol could set
> > the return code if the architecture does not provide support for setting
> > the attributes the passed addresses are invalid.
>
> Sure I'll change that in v2
Okay, I ad a look at EFI_MEMORY_ATTRIBUTE_PROTOCOL.SetMemoryAttributes.
This function does not support EFI_UNSUPPORTED if you don't have code
around to set the PTEs.
So, I think we should
- make the prototype an int and return an error
- add a new bool *supported argument? And if the caller calls the function
with base & size == 0, set that value?
That way we can choose not to install the protocol at all if the
functionality doesn't exist.
Thanks
/Ilias
>
> Cheers
> /Ilias
> >
> > Best regards
> >
> > Heinrich
> >
> > > diff --git a/arch/m68k/lib/cache.c b/arch/m68k/lib/cache.c
> > > index 370ad40f1423..b275646384a5 100644
> > > --- a/arch/m68k/lib/cache.c
> > > +++ b/arch/m68k/lib/cache.c
> > > @@ -151,3 +151,5 @@ __weak void flush_dcache_range(unsigned long start,
> > > unsigned long stop)
> > > {
> > > /* An empty stub, real implementation should be in platform code */
> > > }
> > > +
> > > +void __weak pgprot_set_attrs(phys_addr_t addr, size_t size, u64 perm) {}
> > > diff --git a/arch/nios2/lib/cache.c b/arch/nios2/lib/cache.c
> > > index 8f543f2a2f26..7a93a8fcc6a7 100644
> > > --- a/arch/nios2/lib/cache.c
> > > +++ b/arch/nios2/lib/cache.c
> > > @@ -127,3 +127,5 @@ void dcache_disable(void)
> > > {
> > > flush_dcache_all();
> > > }
> > > +
> > > +void __weak pgprot_set_attrs(phys_addr_t addr, size_t size, u64 perm) {}
> > > diff --git a/arch/powerpc/lib/cache.c b/arch/powerpc/lib/cache.c
> > > index a9cd7b8d30ac..3d0536caccde 100644
> > > --- a/arch/powerpc/lib/cache.c
> > > +++ b/arch/powerpc/lib/cache.c
> > > @@ -58,3 +58,5 @@ void invalidate_icache_all(void)
> > > {
> > > puts("No arch specific invalidate_icache_all available!\n");
> > > }
> > > +
> > > +void __weak pgprot_set_attrs(phys_addr_t addr, size_t size, u64 perm) {}
> > > diff --git a/arch/riscv/lib/cache.c b/arch/riscv/lib/cache.c
> > > index 71e4937ab542..1c751e562157 100644
> > > --- a/arch/riscv/lib/cache.c
> > > +++ b/arch/riscv/lib/cache.c
> > > @@ -151,3 +151,5 @@ __weak void enable_caches(void)
> > > if (!zicbom_block_size)
> > > log_debug("Zicbom not initialized.\n");
> > > }
> > > +
> > > +void __weak pgprot_set_attrs(phys_addr_t addr, size_t size, u64 perm) {}
> > > diff --git a/arch/sh/cpu/sh4/cache.c b/arch/sh/cpu/sh4/cache.c
> > > index 99acc5999652..22e0f1484a33 100644
> > > --- a/arch/sh/cpu/sh4/cache.c
> > > +++ b/arch/sh/cpu/sh4/cache.c
> > > @@ -126,3 +126,5 @@ int dcache_status(void)
> > > {
> > > return 0;
> > > }
> > > +
> > > +void __weak pgprot_set_attrs(phys_addr_t addr, size_t size, u64 perm) {}
> > > diff --git a/arch/xtensa/lib/cache.c b/arch/xtensa/lib/cache.c
> > > index e6a7f6827fc2..aacc2d2627d6 100644
> > > --- a/arch/xtensa/lib/cache.c
> > > +++ b/arch/xtensa/lib/cache.c
> > > @@ -57,3 +57,5 @@ void invalidate_icache_all(void)
> > > {
> > > __invalidate_icache_all();
> > > }
> > > +
> > > +void __weak pgprot_set_attrs(phys_addr_t addr, size_t size, u64 perm) {}
> > > diff --git a/include/cpu_func.h b/include/cpu_func.h
> > > index 7e81c4364a73..17b6d199302a 100644
> > > --- a/include/cpu_func.h
> > > +++ b/include/cpu_func.h
> > > @@ -69,6 +69,22 @@ void flush_dcache_range(unsigned long start, unsigned
> > > long stop);
> > > void invalidate_dcache_range(unsigned long start, unsigned long stop);
> > > void invalidate_dcache_all(void);
> > > void invalidate_icache_all(void);
> > > +
> > > +enum pgprot_attrs {
> > > + MMU_ATTR_RO,
> > > + MMU_ATTR_RX,
> > > + MMU_ATTR_RW,
> > > +};
> > > +
> > > +/** pgprot_set_attrs() - Set page table permissions
> > > + *
> > > + * @addr: Physical address start
> > > + * @size: size of memory to change
> > > + * @perm: New permissions
> > > + *
> > > + **/
> > > +void pgprot_set_attrs(phys_addr_t addr, size_t size, u64 perm);
> > > +
> > > /**
> > > * noncached_init() - Initialize non-cached memory region
> > > *
> >
