[PATCH 03/10] microblaze: cache: improve dcache Kconfig options

[Michal Simek]

On 4/11/22 18:26, Ovidiu Panait wrote:
> Replace CONFIG_DCACHE with a Kconfig option more limited in scope -
> XILINX_MICROBLAZE0_USE_WDC. It should be enabled if the processor supports
> the "wdc" (Write to Data Cache) instruction. It will be used to guard
> "wdc" invocations in microblaze cache code.
> 
> Also, drop all ifdefs around flush_cache() calls and only keep one
> CONFIG_IS_ENABLED() guard within flush_cache() itself.
> 
> Signed-off-by: Ovidiu Panait <ovpanait at gmail.com>
> ---
> 
>   arch/microblaze/Kconfig                 |  4 ----
>   arch/microblaze/cpu/cache.c             | 15 ++++++++++-----
>   arch/microblaze/lib/bootm.c             |  2 --
>   board/xilinx/microblaze-generic/Kconfig |  7 +++++++
>   4 files changed, 17 insertions(+), 11 deletions(-)
> 
> diff --git a/arch/microblaze/Kconfig b/arch/microblaze/Kconfig
> index d7d1b21970..5a2e91104f 100644
> --- a/arch/microblaze/Kconfig
> +++ b/arch/microblaze/Kconfig
> @@ -25,10 +25,6 @@ config TARGET_MICROBLAZE_GENERIC
>   
>   endchoice
>   
> -config DCACHE
> -	bool "Enable dcache support"
> -	default y
> -
>   config ICACHE
>   	bool "Enable icache support"
>   	default y
> diff --git a/arch/microblaze/cpu/cache.c b/arch/microblaze/cpu/cache.c
> index b6126de194..4e8e228a22 100644
> --- a/arch/microblaze/cpu/cache.c
> +++ b/arch/microblaze/cpu/cache.c
> @@ -49,26 +49,31 @@ void dcache_enable(void)
>   
>   void dcache_disable(void)
>   {
> -#ifdef CONFIG_DCACHE
>   	flush_cache(0, XILINX_DCACHE_BYTE_SIZE);
> -#endif
> +
>   	MSRCLR(0x80);
>   }
>   
>   void flush_cache(ulong addr, ulong size)
>   {
>   	int i;
> -	for (i = 0; i < size; i += 4)
> +	for (i = 0; i < size; i += 4) {
>   		asm volatile (
>   #ifdef CONFIG_ICACHE
>   				"wic	%0, r0;"
>   #endif
>   				"nop;"
> -#ifdef CONFIG_DCACHE
> +				:
> +				: "r" (addr + i)
> +				: "memory");
> +
> +		if (CONFIG_IS_ENABLED(XILINX_MICROBLAZE0_USE_WDC)) {


Based on buildman your patch is removing cache handling from SPL.
Here is what I see that there are missing 2 instructions. And 4/10 you see that 
8 instructions are missing.

06: microblaze: cache: improve dcache Kconfig options
microblaze: (for 1/1 boards) spl/u-boot-spl:all -8.0 spl/u-boot-spl:text -8.0
             microblaze-generic: spl/u-boot-spl:all -8 spl/u-boot-spl:text -8
                spl-u-boot-spl: add: 0/0, grow: 0/-1 bytes: 0/-8 (-8)
                  function                                   old     new   delta
                  flush_cache                                 48      40      -8
07: microblaze: cache: improve icache Kconfig options
microblaze: (for 1/1 boards) spl/u-boot-spl:all -32.0 spl/u-boot-spl:text -32.0
             microblaze-generic: spl/u-boot-spl:all -32 spl/u-boot-spl:text -32
                spl-u-boot-spl: add: 0/0, grow: 0/-1 bytes: 0/-32 (-32)
                  function

This is going to macro explanation where it is clear that you don't define 
CONFIG_SPL_FOO you only define CONFIG_FOO.


104  * CONFIG_IS_ENABLED(FOO) expands to
105  *  1 if USE_HOSTCC is defined and CONFIG_TOOLS_FOO is set to 'y',
106  *  1 if CONFIG_SPL_BUILD is undefined and CONFIG_FOO is set to 'y',
107  *  1 if CONFIG_SPL_BUILD is defined and CONFIG_SPL_FOO is set to 'y',
108  *  1 if CONFIG_TPL_BUILD is defined and CONFIG_TPL_FOO is set to 'y',
109  *  0 otherwise.

It means you should use different macro or create one more with SPL.

Thanks,
Michal