Re: [PATCH] LoongArch: Update the flush cache policy

[Xi Ruoyao <xry111@xry111.site>]

On Mon, 2024-05-06 at 17:24 +0800, Li Jun wrote:
> fix when LoongArch s3 resume, Can't find image information
> 
> Signed-off-by: Li Jun <lijun01@kylinos.cn>
> Signed-off-by: Baoqi Zhang <zhangbaoqi@loongson.cn>
> Signed-off-by: Jianmin Lv <lvjianmin@loongson.cn>
> Signed-off-by: Biao Dong <dongbiao@loongson.cn>
> ---
>  arch/loongarch/mm/cache.c | 24 +++++++++++++++++++++++-
>  1 file changed, 23 insertions(+), 1 deletion(-)
> 
> diff --git a/arch/loongarch/mm/cache.c b/arch/loongarch/mm/cache.c
> index 6be04d36ca07..52872fa0e5d8 100644
> --- a/arch/loongarch/mm/cache.c
> +++ b/arch/loongarch/mm/cache.c
> @@ -63,6 +63,28 @@ static void flush_cache_leaf(unsigned int leaf)
>  	} while (--nr_nodes > 0);
>  }
>  
> +static void flush_cache_last_level(unsigned int leaf)
> +{
> +	u64 addr;
> +	int i, j, nr_nodes, way_size;
> +	struct cache_desc *cdesc = current_cpu_data.cache_leaves +
> leaf;
> +
> +	nr_nodes = loongson_sysconf.nr_nodes;
> +
> +	addr = CSR_DMW1_BASE;
> +	iocsr_write32(0x1, 0x280);
> +	way_size = cdesc->sets * cdesc->linesz;
> +	do {
> +		for (i = 0; i < (cdesc->ways * 3); i++) {
> +			for (j = 0; j < (cdesc->sets); j++) {
> +				*(volatile u32 *)addr;

??? what does this line do?

-- 
Xi Ruoyao <xry111@xry111.site>
School of Aerospace Science and Technology, Xidian University