[RFC PATCH 1/4] meminfo: add memory details for armv8

[Jerome Forissier]

Hi Ilias,

On 1/30/25 08:20, Ilias Apalodimas wrote:
> Upcoming patches are mapping memory with RO, RW^X etc permsissions.
> Fix the meminfo command to display them properly
> 
> Signed-off-by: Ilias Apalodimas <ilias.apalodimas at linaro.org>
> ---
>  arch/arm/cpu/armv8/cache_v8.c    | 18 +++++++++++++++++-
>  arch/arm/include/asm/armv8/mmu.h |  2 ++
>  cmd/meminfo.c                    |  5 +++++
>  3 files changed, 24 insertions(+), 1 deletion(-)
> 
> diff --git a/arch/arm/cpu/armv8/cache_v8.c b/arch/arm/cpu/armv8/cache_v8.c
> index 5d6953ffedd1..a4ca56c8ed42 100644
> --- a/arch/arm/cpu/armv8/cache_v8.c
> +++ b/arch/arm/cpu/armv8/cache_v8.c
> @@ -421,7 +421,7 @@ static int count_ranges(void)
>  	return count;
>  }
>  
> -#define ALL_ATTRS (3 << 8 | PMD_ATTRINDX_MASK)
> +#define ALL_ATTRS (3 << 8 | PMD_ATTRMASK)
>  #define PTE_IS_TABLE(pte, level) (pte_type(&(pte)) == PTE_TYPE_TABLE && (level) < 3)
>  
>  enum walker_state {
> @@ -568,6 +568,17 @@ static void pretty_print_table_attrs(u64 pte)
>  static void pretty_print_block_attrs(u64 pte)
>  {
>  	u64 attrs = pte & PMD_ATTRINDX_MASK;
> +	u64 perm_attrs = pte & PMD_ATTRMASK;
> +
> +	if ((perm_attrs & PTE_BLOCK_PXN) && (perm_attrs & PTE_BLOCK_UXN) &&
> +	    perm_attrs & PTE_BLOCK_RO)
> +		printf("%-5s", " | RO");
> +	else if ((perm_attrs & PTE_BLOCK_PXN) && (perm_attrs & PTE_BLOCK_UXN))
> +		printf("%-5s", " | RW");
> +	else if (perm_attrs & PTE_BLOCK_RO)
> +		printf("%-5s", " | RX");
> +	else
> +		printf("%-5s", " | RWX");

We could also print out the unprivileged and privileged permissions
explicitly, for example rwxRWX or rw-RW- etc. but maybe the format
you're proposing is more to the point since it is not detailed
debugging info that we're after.

>  
>  	switch (attrs) {
>  	case PTE_BLOCK_MEMTYPE(MT_DEVICE_NGNRNE):
> @@ -1112,3 +1123,8 @@ void __weak enable_caches(void)
>  	icache_enable();
>  	dcache_enable();
>  }
> +
> +void arch_dump_mem_attrs(void)
> +{
> +	dump_pagetable(gd->arch.tlb_addr, get_tcr(NULL, NULL));
> +}
> diff --git a/arch/arm/include/asm/armv8/mmu.h b/arch/arm/include/asm/armv8/mmu.h
> index 0ab681c893d3..6af8cd111a44 100644
> --- a/arch/arm/include/asm/armv8/mmu.h
> +++ b/arch/arm/include/asm/armv8/mmu.h
> @@ -66,6 +66,7 @@
>  #define PTE_BLOCK_NG		(1 << 11)
>  #define PTE_BLOCK_PXN		(UL(1) << 53)
>  #define PTE_BLOCK_UXN		(UL(1) << 54)
> +#define PTE_BLOCK_RO            (UL(1) << 7)
>  
>  /*
>   * AttrIndx[2:0]
> @@ -75,6 +76,7 @@
>  #define PMD_ATTRMASK		(PTE_BLOCK_PXN		| \
>  				 PTE_BLOCK_UXN		| \
>  				 PMD_ATTRINDX_MASK	| \
> +				 PTE_BLOCK_RO		| \
>  				 PTE_TYPE_VALID)
>  
>  /*
> diff --git a/cmd/meminfo.c b/cmd/meminfo.c
> index 5e83d61c2dd3..3915e2bbb268 100644
> --- a/cmd/meminfo.c
> +++ b/cmd/meminfo.c
> @@ -15,6 +15,10 @@
>  
>  DECLARE_GLOBAL_DATA_PTR;
>  
> +void __weak arch_dump_mem_attrs(void)
> +{
> +}
> +
>  static void print_region(const char *name, ulong base, ulong size, ulong *uptop)
>  {
>  	ulong end = base + size;
> @@ -54,6 +58,7 @@ static int do_meminfo(struct cmd_tbl *cmdtp, int flag, int argc,
>  
>  	puts("DRAM:  ");
>  	print_size(gd->ram_size, "\n");
> +	arch_dump_mem_attrs();
>  
>  	if (!IS_ENABLED(CONFIG_CMD_MEMINFO_MAP))
>  		return 0;

Acked-by: Jerome Forissier <jerome.forissier at linaro.org>