[PATCH 1/3] arm64: Convert core type check macros into inline functions

[Marek Vasut]

On 12/16/24 9:54 AM, Biju Das wrote:
> Hi Marek,
> 
> Thanks for the patch.
> 
>> -----Original Message-----
>> From: Marek Vasut <marek.vasut+renesas at mailbox.org>
>> Sent: 14 December 2024 22:43
>> Subject: [PATCH 1/3] arm64: Convert core type check macros into inline functions
>>
>> Turn the core type check macros into inline functions to perform better type checking on them. The
>> inline functions get optimized out in case they are not used. Indent the MIDR_PARTNUM_CORTEX_An macros
>> in preparation for addition of future three-digit cores and use MIDR_PARTNUM_SHIFT in
>> MIDR_PARTNUM_MASK to be consistent.
>>
>> Signed-off-by: Marek Vasut <marek.vasut+renesas at mailbox.org>
>> ---
>> Cc: Biju Das <biju.das.jz at bp.renesas.com>
>> Cc: Chris Paterson <chris.paterson2 at renesas.com>
>> Cc: Lad Prabhakar <prabhakar.mahadev-lad.rj at bp.renesas.com>
>> Cc: Nobuhiro Iwamatsu <iwamatsu at nigauri.org>
>> Cc: Paul Barker <paul.barker.ct at bp.renesas.com>
>> Cc: Tom Rini <trini at konsulko.com>
>> Cc: u-boot at lists.denx.de
>> ---
>>   arch/arm/include/asm/armv8/cpu.h | 28 +++++++++++++++++-----------
>>   1 file changed, 17 insertions(+), 11 deletions(-)
>>
>> diff --git a/arch/arm/include/asm/armv8/cpu.h b/arch/arm/include/asm/armv8/cpu.h
>> index 40d54dc85ab..aa1470bb72d 100644
>> --- a/arch/arm/include/asm/armv8/cpu.h
>> +++ b/arch/arm/include/asm/armv8/cpu.h
>> @@ -3,11 +3,11 @@
>>    * Copyright 2018 NXP
>>    */
>>
>> -#define MIDR_PARTNUM_CORTEX_A35	0xD04
>> -#define MIDR_PARTNUM_CORTEX_A53	0xD03
>> -#define MIDR_PARTNUM_CORTEX_A72	0xD08
>> -#define MIDR_PARTNUM_SHIFT	0x4
>> -#define MIDR_PARTNUM_MASK	(0xFFF << 0x4)
>> +#define MIDR_PARTNUM_CORTEX_A35		0xD04
>> +#define MIDR_PARTNUM_CORTEX_A53		0xD03
>> +#define MIDR_PARTNUM_CORTEX_A72		0xD08
>> +#define MIDR_PARTNUM_SHIFT		0x4
>> +#define MIDR_PARTNUM_MASK		(0xFFF << MIDR_PARTNUM_SHIFT)
>>
>>   static inline unsigned int read_midr(void)  { @@ -18,9 +18,15 @@ static inline unsigned int
>> read_midr(void)
>>   	return val;
>>   }
>>
>> -#define is_cortex_a35() (((read_midr() & MIDR_PARTNUM_MASK) >> \
>> -			 MIDR_PARTNUM_SHIFT) == MIDR_PARTNUM_CORTEX_A35)
>> -#define is_cortex_a53() (((read_midr() & MIDR_PARTNUM_MASK) >> \
>> -			 MIDR_PARTNUM_SHIFT) == MIDR_PARTNUM_CORTEX_A53)
>> -#define is_cortex_a72() (((read_midr() & MIDR_PARTNUM_MASK) >>\
>> -			 MIDR_PARTNUM_SHIFT) == MIDR_PARTNUM_CORTEX_A72)
>> +#define is_cortex_a(__n)					\
>> +	static inline int is_cortex_a##__n(void)		\
>> +	{							\
>> +		unsigned int midr = read_midr();		\
> 
> Maybe unsigned int midr = read_midr() & MIDR_PARTNUM_MASK, to reduce one store
> Operation???
The compiler will optimize the result as needed, this expansion here is 
for readability purpose only.