Re: [PATCH V2 1/3] efi: arch, x86: arch, ia64: move efi_mem_attributes()

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

Thank you for the feedback, Matt.

Given that IA64 does not set EFI_MEMMAP, it appears to me there
are following options:
A. Keep status quota and copy x86's efi_mem_attributes() code
to arm64.
B. In efi subsystem, provide week default efi_mem_attributes().
In the mean time, IA64 continues to have its own implementation.
C. Add EFI_MEMMAP support (and related bits) in IA64.

Which option do you prefer? Once there is a consensus, I am
willing to submit patch accordingly for review.

Regards,
Jonathan

On 6/2/2015 6:36 AM, Matt Fleming wrote:
> (Cc'ing Tony for ia64 input)
>
> On Mon, 01 Jun, at 12:12:18PM, Jonathan (Zhixiong) Zhang wrote:
>> From: "Jonathan (Zhixiong) Zhang" <zjzhang@codeaurora.org>
>>
>> Both x86 and ia64 implemented efi_mem_attributs(), which is architecture
>> agnositc. This function is moved from arch/x86 and arch/ia64 to
>> drivers/firmware/efi.
>>
>> Signed-off-by: Jonathan (Zhixiong) Zhang <zjzhang@codeaurora.org>
>> ---
>>   arch/ia64/kernel/efi.c      | 11 -----------
>>   arch/x86/platform/efi/efi.c | 18 ------------------
>>   drivers/firmware/efi/efi.c  | 18 ++++++++++++++++++
>>   3 files changed, 18 insertions(+), 29 deletions(-)
>>
>> diff --git a/arch/ia64/kernel/efi.c b/arch/ia64/kernel/efi.c
>> index c52d7540dc05..ef20ec784b04 100644
>> --- a/arch/ia64/kernel/efi.c
>> +++ b/arch/ia64/kernel/efi.c
>> @@ -771,17 +771,6 @@ efi_mem_type (unsigned long phys_addr)
>>   }
>>
>>   u64
>> -efi_mem_attributes (unsigned long phys_addr)
>> -{
>> -	efi_memory_desc_t *md = efi_memory_descriptor(phys_addr);
>> -
>> -	if (md)
>> -		return md->attribute;
>> -	return 0;
>> -}
>> -EXPORT_SYMBOL(efi_mem_attributes);
>> -
>> -u64
>>   efi_mem_attribute (unsigned long phys_addr, unsigned long size)
>>   {
>>   	unsigned long end = phys_addr + size;
>> diff --git a/arch/x86/platform/efi/efi.c b/arch/x86/platform/efi/efi.c
>> index 02744df576d5..10bd5289c593 100644
>> --- a/arch/x86/platform/efi/efi.c
>> +++ b/arch/x86/platform/efi/efi.c
>> @@ -926,24 +926,6 @@ u32 efi_mem_type(unsigned long phys_addr)
>>   	return 0;
>>   }
>>
>> -u64 efi_mem_attributes(unsigned long phys_addr)
>> -{
>> -	efi_memory_desc_t *md;
>> -	void *p;
>> -
>> -	if (!efi_enabled(EFI_MEMMAP))
>> -		return 0;
>> -
>> -	for (p = memmap.map; p < memmap.map_end; p += memmap.desc_size) {
>> -		md = p;
>> -		if ((md->phys_addr <= phys_addr) &&
>> -		    (phys_addr < (md->phys_addr +
>> -				  (md->num_pages << EFI_PAGE_SHIFT))))
>> -			return md->attribute;
>> -	}
>> -	return 0;
>> -}
>> -
>>   static int __init arch_parse_efi_cmdline(char *str)
>>   {
>>   	if (parse_option_str(str, "old_map"))
>> diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c
>> index 3061bb8629dc..86da85368778 100644
>> --- a/drivers/firmware/efi/efi.c
>> +++ b/drivers/firmware/efi/efi.c
>> @@ -517,3 +517,21 @@ char * __init efi_md_typeattr_format(char *buf, size_t size,
>>   			 attr & EFI_MEMORY_UC      ? "UC"  : "");
>>   	return buf;
>>   }
>> +
>> +u64 efi_mem_attributes(unsigned long phys_addr)
>> +{
>> +	efi_memory_desc_t *md;
>> +	void *p;
>> +
>> +	if (!efi_enabled(EFI_MEMMAP))
>> +		return 0;
>> +
>
> Umm... ia64 doesn't appear to set EFI_MEMMAP. So doesn't this change
> actively break ia64?
>
> While I like the idea of de-duplication, the two implementations of
> efi_mem_attributes() are not equivalent.
>

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