Re: [PATCH V8 4/5] arm64: apei: implement arch_apei_get_mem_attributes()

["Zhang, Jonathan Zhixiong" <zjzhang@codeaurora.org>]

On 7/27/2015 3:03 AM, Catalin Marinas wrote:
> On Sat, Jul 25, 2015 at 12:51:08AM +0100, Jonathan (Zhixiong) Zhang wrote:
>> From: "Jonathan (Zhixiong) Zhang" <zjzhang@codeaurora.org>
>>
>> Table 8 of UEFI 2.5 section 2.3.6.1 defines mappings from EFI
>> memory types to MAIR attribute encodings for arm64.
>>
>> If the physical address has memory attributes defined by EFI
>> memmap as EFI_MEMORY_[UC|WC|WT], return approprate page protection
>> type. Otherwise, return PAGE_KERNEL.
>>
>> Change-Id: I7f836cae0fb3e74a34e27ac695c2637ffc4cddc6
>> Acked-by: Hanjun Guo <hanjun.guo@linaro.org>
>> Signed-off-by: Jonathan (Zhixiong) Zhang <zjzhang@codeaurora.org>
>
> Same comment about the Change-Id.
Yes.
>
>> ---
>>   arch/arm64/include/asm/acpi.h | 26 ++++++++++++++++++++++++++
>>   1 file changed, 26 insertions(+)
>>
>> diff --git a/arch/arm64/include/asm/acpi.h b/arch/arm64/include/asm/acpi.h
>> index 1ff9e6eb5e02..04720f819f0a 100644
>> --- a/arch/arm64/include/asm/acpi.h
>> +++ b/arch/arm64/include/asm/acpi.h
>> @@ -19,6 +19,11 @@
>>   #include <asm/psci.h>
>>   #include <asm/smp_plat.h>
>>
>> +#ifdef CONFIG_ACPI_APEI
>> +#include <linux/efi.h>
>> +#include <asm/pgtable.h>
>> +#endif
>> +
>>   /* Macros for consistency checks of the GICC subtable of MADT */
>>   #define ACPI_MADT_GICC_LENGTH	\
>>   	(acpi_gbl_FADT.header.revision < 6 ? 76 : 80)
>> @@ -91,4 +95,26 @@ static inline const char *acpi_get_enable_method(int cpu)
>>   {
>>   	return acpi_psci_present() ? "psci" : NULL;
>>   }
>> +
>> +#ifdef	CONFIG_ACPI_APEI
>> +/*
>> + * According to "Table 8 Map: EFI memory types to AArch64 memory types"
>> + * of UEFI 2.5 section 2.3.6.1, each EFI memory type is mapped to
>> + * corresponding MAIR attribute encoding.
>> + */
>> +static inline pgprot_t arch_apei_get_mem_attribute(phys_addr_t addr)
>> +{
>> +	u64 attr;
>> +
>> +	attr = efi_mem_attributes(addr);
>> +	if (attr & EFI_MEMORY_UC)
>> +		return PROT_DEVICE_nGnRnE;
>> +	if (attr & EFI_MEMORY_WC)
>> +		return PROT_NORMAL_NC;
>> +	if (attr & EFI_MEMORY_WT)
>> +		return PROT_NORMAL_WT;
>
> Just to match the strict mm types, please add __pgprot(PROT_*) here.
>
>> +	return PAGE_KERNEL;
Will do.
>
> Otherwise:
>
> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Thanks.

-- 
Jonathan (Zhixiong) Zhang
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project