From 663db206f85653f05c5f6adb577970cc4669a7ea Mon Sep 17 00:00:00 2001 From: Soby Mathew Date: Thu, 9 Jun 2016 17:16:35 +0100 Subject: Derive stack alignment from CACHE_WRITEBACK_GRANULE The per-cpu stacks should be aligned to the cache-line size and the `declare_stack` helper in asm_macros.S macro assumed a cache-line size of 64 bytes. The platform defines the cache-line size via CACHE_WRITEBACK_GRANULE macro. This patch modifies `declare_stack` helper macro to derive stack alignment from the platform defined macro. Change-Id: I1e1b00fc8806ecc88190ed169f4c8d3dd25fe95b --- include/common/asm_macros.S | 24 ++++++++++++++++++++---- 1 file changed, 20 insertions(+), 4 deletions(-) (limited to 'include/common/asm_macros.S') diff --git a/include/common/asm_macros.S b/include/common/asm_macros.S index d4bd11ee..bd8bb709 100644 --- a/include/common/asm_macros.S +++ b/include/common/asm_macros.S @@ -147,18 +147,34 @@ .endm #endif + /* + * Helper assembler macro to count trailing zeros. The output is + * populated in the `TZ_COUNT` symbol. + */ + .macro count_tz _value, _tz_count + .if \_value + count_tz "(\_value >> 1)", "(\_tz_count + 1)" + .else + .equ TZ_COUNT, (\_tz_count - 1) + .endif + .endm + /* * This macro declares an array of 1 or more stacks, properly * aligned and in the requested section */ -#define STACK_ALIGN 6 +#define DEFAULT_STACK_ALIGN (1 << 6) /* In case the caller doesnt provide alignment */ - .macro declare_stack _name, _section, _size, _count - .if ((\_size & ((1 << STACK_ALIGN) - 1)) <> 0) + .macro declare_stack _name, _section, _size, _count, _align=DEFAULT_STACK_ALIGN + count_tz \_align, 0 + .if (\_align - (1 << TZ_COUNT)) + .error "Incorrect stack alignment specified (Must be a power of 2)." + .endif + .if ((\_size & ((1 << TZ_COUNT) - 1)) <> 0) .error "Stack size not correctly aligned" .endif .section \_section, "aw", %nobits - .align STACK_ALIGN + .align TZ_COUNT \_name: .space ((\_count) * (\_size)), 0 .endm -- cgit