Re: [PATCH v2 1/5] cacheinfo: Use RISC-V's init_cache_level() as generic OF implementation

[Palmer Dabbelt]

On Mon, 21 Nov 2022 09:12:09 PST (-0800), pierre.gondois@xxxxxxx wrote:
> RISC-V's implementation of init_of_cache_level() is following
> the Devicetree Specification v0.3 regarding caches, cf.:
> - s3.7.3 'Internal (L1) Cache Properties'
> - s3.8 'Multi-level and Shared Cache Nodes'
>
> Allow reusing the implementation by moving it.
>
> Signed-off-by: Pierre Gondois <pierre.gondois@xxxxxxx>
> Reviewed-by: Conor Dooley <conor.dooley@xxxxxxxxxxxxx>
> Reviewed-by: Sudeep Holla <sudeep.holla@xxxxxxx>
> ---
>  arch/riscv/kernel/cacheinfo.c | 39 +------------------------------
>  drivers/base/cacheinfo.c      | 44 +++++++++++++++++++++++++++++++++++
>  include/linux/cacheinfo.h     |  1 +
>  3 files changed, 46 insertions(+), 38 deletions(-)
>
> diff --git a/arch/riscv/kernel/cacheinfo.c b/arch/riscv/kernel/cacheinfo.c
> index 90deabfe63ea..440a3df5944c 100644
> --- a/arch/riscv/kernel/cacheinfo.c
> +++ b/arch/riscv/kernel/cacheinfo.c
> @@ -115,44 +115,7 @@ static void fill_cacheinfo(struct cacheinfo **this_leaf,
>
>  int init_cache_level(unsigned int cpu)
>  {
> -	struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(cpu);
> -	struct device_node *np = of_cpu_device_node_get(cpu);
> -	struct device_node *prev = NULL;
> -	int levels = 0, leaves = 0, level;
> -
> -	if (of_property_read_bool(np, "cache-size"))
> -		++leaves;
> -	if (of_property_read_bool(np, "i-cache-size"))
> -		++leaves;
> -	if (of_property_read_bool(np, "d-cache-size"))
> -		++leaves;
> -	if (leaves > 0)
> -		levels = 1;
> -
> -	prev = np;
> -	while ((np = of_find_next_cache_node(np))) {
> -		of_node_put(prev);
> -		prev = np;
> -		if (!of_device_is_compatible(np, "cache"))
> -			break;
> -		if (of_property_read_u32(np, "cache-level", &level))
> -			break;
> -		if (level <= levels)
> -			break;
> -		if (of_property_read_bool(np, "cache-size"))
> -			++leaves;
> -		if (of_property_read_bool(np, "i-cache-size"))
> -			++leaves;
> -		if (of_property_read_bool(np, "d-cache-size"))
> -			++leaves;
> -		levels = level;
> -	}
> -
> -	of_node_put(np);
> -	this_cpu_ci->num_levels = levels;
> -	this_cpu_ci->num_leaves = leaves;
> -
> -	return 0;
> +	return init_of_cache_level(cpu);
>  }
>
>  int populate_cache_leaves(unsigned int cpu)
> diff --git a/drivers/base/cacheinfo.c b/drivers/base/cacheinfo.c
> index 4b5cd08c5a65..a4308b48dd3e 100644
> --- a/drivers/base/cacheinfo.c
> +++ b/drivers/base/cacheinfo.c
> @@ -224,8 +224,52 @@ static int cache_setup_of_node(unsigned int cpu)
>
>  	return 0;
>  }
> +
> +int init_of_cache_level(unsigned int cpu)
> +{
> +	struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(cpu);
> +	struct device_node *np = of_cpu_device_node_get(cpu);
> +	struct device_node *prev = NULL;
> +	int levels = 0, leaves = 0, level;
> +
> +	if (of_property_read_bool(np, "cache-size"))
> +		++leaves;
> +	if (of_property_read_bool(np, "i-cache-size"))
> +		++leaves;
> +	if (of_property_read_bool(np, "d-cache-size"))
> +		++leaves;
> +	if (leaves > 0)
> +		levels = 1;
> +
> +	prev = np;
> +	while ((np = of_find_next_cache_node(np))) {
> +		of_node_put(prev);
> +		prev = np;
> +		if (!of_device_is_compatible(np, "cache"))
> +			break;
> +		if (of_property_read_u32(np, "cache-level", &level))
> +			break;
> +		if (level <= levels)
> +			break;
> +		if (of_property_read_bool(np, "cache-size"))
> +			++leaves;
> +		if (of_property_read_bool(np, "i-cache-size"))
> +			++leaves;
> +		if (of_property_read_bool(np, "d-cache-size"))
> +			++leaves;
> +		levels = level;
> +	}
> +
> +	of_node_put(np);
> +	this_cpu_ci->num_levels = levels;
> +	this_cpu_ci->num_leaves = leaves;
> +
> +	return 0;
> +}
> +
>  #else
>  static inline int cache_setup_of_node(unsigned int cpu) { return 0; }
> +int init_of_cache_level(unsigned int cpu) { return 0; }
>  #endif
>
>  int __weak cache_setup_acpi(unsigned int cpu)
> diff --git a/include/linux/cacheinfo.h b/include/linux/cacheinfo.h
> index 00b7a6ae8617..ff0328f3fbb0 100644
> --- a/include/linux/cacheinfo.h
> +++ b/include/linux/cacheinfo.h
> @@ -80,6 +80,7 @@ struct cpu_cacheinfo {
>
>  struct cpu_cacheinfo *get_cpu_cacheinfo(unsigned int cpu);
>  int init_cache_level(unsigned int cpu);
> +int init_of_cache_level(unsigned int cpu);
>  int populate_cache_leaves(unsigned int cpu);
>  int cache_setup_acpi(unsigned int cpu);
>  bool last_level_cache_is_valid(unsigned int cpu);

Acked-by: Palmer Dabbelt <palmer@xxxxxxxxxxxx>