Re: [PATCH v3 5/5] ACPI: ARM64: support for ACPI_TABLE_UPGRADE

[Aleksey Makarov]

On 06/02/2016 08:49 PM, Aleksey Makarov wrote:
> From: Jon Masters <jcm@xxxxxxxxxx>
> 
> This patch adds support for ACPI_TABLE_UPGRADE for ARM64

Hi Catalin, Will,

Can you review this v3 patch please?  I changed PFN_PHYS(max_pfn) to
MEMBLOCK_ALLOC_ACCESSIBLE.

Thank you
Aleksey Makarov

> To access initrd image we need to move initialization
> of linear mapping a bit earlier.
> 
> The implementation of the feature acpi_table_upgrade()
> (drivers/acpi/tables.c) works with initrd data represented as an array
> in virtual memory.  It uses some library utility to find the redefined
> tables in that array and iterates over it to copy the data to new
> allocated memory.  So to access the initrd data via fixmap
> we need to rewrite it considerably.
> 
> In x86 arch, kernel memory is already mapped by the time when
> acpi_table_upgrade() and acpi_boot_table_init() are called so I
> think that we can just move this mapping one function earlier too.
> 
> Signed-off-by: Jon Masters <jcm@xxxxxxxxxx>
> Signed-off-by: Aleksey Makarov <aleksey.makarov@xxxxxxxxxx>
> ---
>  arch/arm64/Kconfig            | 1 +
>  arch/arm64/include/asm/acpi.h | 2 ++
>  arch/arm64/kernel/setup.c     | 6 ++++--
>  3 files changed, 7 insertions(+), 2 deletions(-)
> 
> diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
> index 87c48ad..baee459 100644
> --- a/arch/arm64/Kconfig
> +++ b/arch/arm64/Kconfig
> @@ -5,6 +5,7 @@ config ARM64
>  	select ACPI_REDUCED_HARDWARE_ONLY if ACPI
>  	select ACPI_MCFG if ACPI
>  	select ARCH_HAS_DEVMEM_IS_ALLOWED
> +	select ARCH_HAS_ACPI_TABLE_UPGRADE if ACPI
>  	select ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE
>  	select ARCH_HAS_ELF_RANDOMIZE
>  	select ARCH_HAS_GCOV_PROFILE_ALL
> diff --git a/arch/arm64/include/asm/acpi.h b/arch/arm64/include/asm/acpi.h
> index aee323b..c7aefc5 100644
> --- a/arch/arm64/include/asm/acpi.h
> +++ b/arch/arm64/include/asm/acpi.h
> @@ -113,4 +113,6 @@ static inline const char *acpi_get_enable_method(int cpu)
>  pgprot_t arch_apei_get_mem_attribute(phys_addr_t addr);
>  #endif
>  
> +#define ACPI_TABLE_UPGRADE_MAX_PHYS MEMBLOCK_ALLOC_ACCESSIBLE
> +
>  #endif /*_ASM_ACPI_H*/
> diff --git a/arch/arm64/kernel/setup.c b/arch/arm64/kernel/setup.c
> index feab2ee..4bce811 100644
> --- a/arch/arm64/kernel/setup.c
> +++ b/arch/arm64/kernel/setup.c
> @@ -261,11 +261,13 @@ void __init setup_arch(char **cmdline_p)
>  	efi_init();
>  	arm64_memblock_init();
>  
> +	paging_init();
> +
> +	acpi_table_upgrade();
> +
>  	/* Parse the ACPI tables for possible boot-time configuration */
>  	acpi_boot_table_init();
>  
> -	paging_init();
> -
>  	if (acpi_disabled)
>  		unflatten_device_tree();
>  
>