[PATCH 2/2] platform: introduce DT-based configurable heap size

[Xiang W]

在 2024-09-16星期一的 15:25 +0800，Inochi Amaoto写道：
> The default heap size will work for most platforms, but for some
> special platforms, the heap is too small to hold all the information
> or is too big so that it take too much ram. Introduce configurable
> heap should solve this problem and make all generic platforms happy.
> 
> Add DT-based heap-size for the generic platform.
> 
> Signed-off-by: Inochi Amaoto <inochiama at gmail.com>
LGTM

Reviewed-by: Xiang W <wxjstz at 126.com>
> ---
>  docs/opensbi_config.md      |  4 ++++
>  platform/generic/platform.c | 28 +++++++++++++++++++++++++---
>  2 files changed, 29 insertions(+), 3 deletions(-)
> 
> diff --git a/docs/opensbi_config.md b/docs/opensbi_config.md
> index 1b710f1..c620379 100644
> --- a/docs/opensbi_config.md
> +++ b/docs/opensbi_config.md
> @@ -23,6 +23,9 @@ The DT properties of a domain configuration DT node are as follows:
>    set of harts is permitted to perform a cold boot. Otherwise, all
>    harts are allowed to cold boot.
>  
> +* **heap-size** (Optional) - When present, the SBI will initialize
> +  the heap with the set value (This value is in byte).
> +
>  * **system-suspend-test** (Optional) - When present, enable a system
>    suspend test implementation which simply waits five seconds and issues a WFI.
>  
> @@ -36,6 +39,7 @@ The OpenSBI Configuration Node will be deleted at the end of cold boot
>          opensbi-config {
>              compatible = "opensbi,config";
>              cold-boot-harts = <&cpu1 &cpu2 &cpu3 &cpu4>;
> +            heap-size = <0x400000>;
>              system-suspend-test;
>          };
>      };
> diff --git a/platform/generic/platform.c b/platform/generic/platform.c
> index 49d877d..c8e988e 100644
> --- a/platform/generic/platform.c
> +++ b/platform/generic/platform.c
> @@ -69,6 +69,28 @@ static u32 fw_platform_calculate_heap_size(u32 hart_count)
>  	return BIT_ALIGN(heap_size, HEAP_BASE_ALIGN);
>  }
>  
> +static u32 fw_platform_get_heap_size(const void *fdt, u32 hart_count)
> +{
> +	int chosen_offset, config_offset, len;
> +	const fdt32_t *val;
> +
> +	/* Get the heap size from device tree */
> +	chosen_offset = fdt_path_offset(fdt, "/chosen");
> +	if (chosen_offset < 0)
> +		goto default_config;
> +
> +	config_offset = fdt_node_offset_by_compatible(fdt, chosen_offset, "opensbi,config");
> +	if (config_offset < 0)
> +		goto default_config;
> +
> +	val = (fdt32_t *)fdt_getprop(fdt, config_offset, "heap-size", &len);
> +	if (len > 0 && val)
> +		return fdt32_to_cpu(*val);
> +
> +default_config:
> +	return fw_platform_calculate_heap_size(hart_count);
> +}
> +
>  extern struct sbi_platform platform;
>  static bool platform_has_mlevel_imsic = false;
>  static u32 generic_hart_index2id[SBI_HARTMASK_MAX_BITS] = { 0 };
> @@ -76,9 +98,9 @@ static u32 generic_hart_index2id[SBI_HARTMASK_MAX_BITS] = { 0 };
>  static DECLARE_BITMAP(generic_coldboot_harts, SBI_HARTMASK_MAX_BITS);
>  
>  /*
> - * The fw_platform_coldboot_harts_init() function is called by fw_platform_init() 
> + * The fw_platform_coldboot_harts_init() function is called by fw_platform_init()
>   * function to initialize the cold boot harts allowed by the generic platform
> - * according to the DT property "cold-boot-harts" in "/chosen/opensbi-config" 
> + * according to the DT property "cold-boot-harts" in "/chosen/opensbi-config"
>   * DT node. If there is no "cold-boot-harts" in DT, all harts will be allowed.
>   */
>  static void fw_platform_coldboot_harts_init(const void *fdt)
> @@ -185,7 +207,7 @@ unsigned long fw_platform_init(unsigned long arg0, unsigned long arg1,
>  	}
>  
>  	platform.hart_count = hart_count;
> -	platform.heap_size = fw_platform_calculate_heap_size(hart_count);
> +	platform.heap_size = fw_platform_get_heap_size(fdt, hart_count);
>  	platform_has_mlevel_imsic = fdt_check_imsic_mlevel(fdt);
>  
>  	fw_platform_coldboot_harts_init(fdt);