Re: [PATCH v7 07/13] drivers: base cacheinfo: Add support for ACPI based firmware tables

[Sudeep Holla <sudeep.holla@arm.com>]

On 28/02/18 22:06, Jeremy Linton wrote:
> Call ACPI cache parsing routines from base cacheinfo code if ACPI
> is enable. Also stub out cache_setup_acpi() so that individual
> architectures can enable ACPI topology parsing.
> 
> Signed-off-by: Jeremy Linton <jeremy.linton@arm.com>
> ---
>  drivers/acpi/pptt.c       |  1 +
>  drivers/base/cacheinfo.c  | 14 ++++++++++----
>  include/linux/cacheinfo.h |  9 +++++++++
>  3 files changed, 20 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/acpi/pptt.c b/drivers/acpi/pptt.c
> index 883e4318c6cd..c98f94ebd272 100644
> --- a/drivers/acpi/pptt.c
> +++ b/drivers/acpi/pptt.c
> @@ -343,6 +343,7 @@ static void update_cache_properties(struct cacheinfo *this_leaf,
>  {
>  	int valid_flags = 0;
>  
> +	this_leaf->fw_token = cpu_node;


Any reason why this can't part of 05/13 ?

>  	if (found_cache->flags & ACPI_PPTT_SIZE_PROPERTY_VALID) {
>  		this_leaf->size = found_cache->size;
>  		valid_flags++;
> diff --git a/drivers/base/cacheinfo.c b/drivers/base/cacheinfo.c
> index 597aacb233fc..2880e2ab01f5 100644
> --- a/drivers/base/cacheinfo.c
> +++ b/drivers/base/cacheinfo.c
> @@ -206,7 +206,7 @@ static inline bool cache_leaves_are_shared(struct cacheinfo *this_leaf,
>  					   struct cacheinfo *sib_leaf)
>  {
>  	/*
> -	 * For non-DT systems, assume unique level 1 cache, system-wide
> +	 * For non-DT/ACPI systems, assume unique level 1 caches, system-wide
>  	 * shared caches for all other levels. This will be used only if
>  	 * arch specific code has not populated shared_cpu_map
>  	 */
> @@ -214,6 +214,11 @@ static inline bool cache_leaves_are_shared(struct cacheinfo *this_leaf,
>  }
>  #endif
>  
> +int __weak cache_setup_acpi(unsigned int cpu)
> +{
> +	return -ENOTSUPP;
> +}
> +
>  static int cache_shared_cpu_map_setup(unsigned int cpu)
>  {
>  	struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(cpu);
> @@ -227,8 +232,8 @@ static int cache_shared_cpu_map_setup(unsigned int cpu)
>  	if (of_have_populated_dt())
>  		ret = cache_setup_of_node(cpu);
>  	else if (!acpi_disabled)
> -		/* No cache property/hierarchy support yet in ACPI */
> -		ret = -ENOTSUPP;
> +		ret = cache_setup_acpi(cpu);
> +
>  	if (ret)
>  		return ret;
>  
> @@ -279,7 +284,8 @@ static void cache_shared_cpu_map_remove(unsigned int cpu)
>  			cpumask_clear_cpu(cpu, &sib_leaf->shared_cpu_map);
>  			cpumask_clear_cpu(sibling, &this_leaf->shared_cpu_map);
>  		}
> -		of_node_put(this_leaf->fw_token);
> +		if (of_have_populated_dt())
> +			of_node_put(this_leaf->fw_token);
>  	}
>  }
>  
> diff --git a/include/linux/cacheinfo.h b/include/linux/cacheinfo.h
> index 0c6f658054d2..1446d3f053a2 100644
> --- a/include/linux/cacheinfo.h
> +++ b/include/linux/cacheinfo.h
> @@ -97,6 +97,15 @@ int func(unsigned int cpu)					\
>  struct cpu_cacheinfo *get_cpu_cacheinfo(unsigned int cpu);
>  int init_cache_level(unsigned int cpu);
>  int populate_cache_leaves(unsigned int cpu);
> +int cache_setup_acpi(unsigned int cpu);
> +int acpi_find_last_cache_level(unsigned int cpu);
> +#ifndef CONFIG_ACPI
> +int acpi_find_last_cache_level(unsigned int cpu)

The above 3 lines looks weird, can't it be:

#ifdef CONFIG_ACPI
int acpi_find_last_cache_level(unsigned int cpu);
#else
int acpi_find_last_cache_level(unsigned int cpu)
{
	/* ACPI kernels should be built with PPTT support */
	return 0;
}

Also I think it should be CONFIG_ACPI_PPTT, otherwise it might cause
issue on platforms which define CONFIG_ACPI but CONFIG_ACPI_PPTT is not.
I can only relate this to the s390 error reported by kbuild robot.

-- 
Regards,
Sudeep