[PATCH] arm64: head: remove __PHYS_OFFSET

[Anshuman Khandual]

On 6/28/22 12:55, Ard Biesheuvel wrote:
> On Tue, 28 Jun 2022 at 06:57, Anshuman Khandual
> <anshuman.khandual at arm.com> wrote:
>> From: Mark Rutland <mark.rutland at arm.com>
>>
>> It's very easy to confuse __PHYS_OFFSET and PHYS_OFFSET. To clarify
>> things, let's remove __PHYS_OFFSET and use KERNEL_START directly, with
>> comments to show that we're using physical address, as we do for other
>> objects.
>>
>> At the same time, update the comment regarding the kernel entry address
>> to mention __pa(KERNEL_START) rather than __pa(PAGE_OFFSET).
>>
>> There should be no functional change as a result of this patch.
>>
>> Cc: Ard Biesheuvel <ardb at kernel.org>
>> Cc: Catalin Marinas <catalin.marinas at arm.com>
>> Cc: Will Deacon <will at kernel.org>
>> Acked-by: Ard Biesheuvel <ardb at kernel.org>
>> Signed-off-by: Mark Rutland <mark.rutland at arm.com>
>> Signed-off-by: Anshuman Khandual <anshuman.khandual at arm.com>
>> ---
>> This applies on latest arm64 kernel (for-next/boot).
>>
>>  arch/arm64/kernel/head.S | 10 ++++------
>>  1 file changed, 4 insertions(+), 6 deletions(-)
>>
>> diff --git a/arch/arm64/kernel/head.S b/arch/arm64/kernel/head.S
>> index 6bf685f988f1..763f11a394a7 100644
>> --- a/arch/arm64/kernel/head.S
>> +++ b/arch/arm64/kernel/head.S
>> @@ -37,8 +37,6 @@
>>
>>  #include "efi-header.S"
>>
>> -#define __PHYS_OFFSET  KERNEL_START
>> -
>>  #if (PAGE_OFFSET & 0x1fffff) != 0
>>  #error PAGE_OFFSET must be at least 2MB aligned
>>  #endif
>> @@ -52,7 +50,7 @@
>>   *   x0 = physical address to the FDT blob.
>>   *
>>   * This code is mostly position independent so you call this at
>> - * __pa(PAGE_OFFSET).
>> + * __pa(KERNEL_START).
>>   *
> I'm now wondering whether we should just drop this comment - it is no
> longer accurate, and of dubious value even when it was.

Sure, will drop those two comment lines.