[ARM] ARMv6: add CPU_HAS_ASID configuration
Presently, we check for the minimum ARM architecture that we're
building for to determine whether we need ASID support. This is
wrong - if we're going to support a range of CPUs which include
ARMv6 or higher, we need the ASID.
Convert the checks to use a new configuration symbol, and arrange
for ARMv6 and higher CPU entries to select it.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/arch/arm/kernel/asm-offsets.c b/arch/arm/kernel/asm-offsets.c
index 3c078e3..3278e71 100644
--- a/arch/arm/kernel/asm-offsets.c
+++ b/arch/arm/kernel/asm-offsets.c
@@ -85,7 +85,7 @@
DEFINE(S_OLD_R0, offsetof(struct pt_regs, ARM_ORIG_r0));
DEFINE(S_FRAME_SIZE, sizeof(struct pt_regs));
BLANK();
-#if __LINUX_ARM_ARCH__ >= 6
+#ifdef CONFIG_CPU_HAS_ASID
DEFINE(MM_CONTEXT_ID, offsetof(struct mm_struct, context.id));
BLANK();
#endif
diff --git a/arch/arm/mm/Kconfig b/arch/arm/mm/Kconfig
index 15f0284..5f472a8 100644
--- a/arch/arm/mm/Kconfig
+++ b/arch/arm/mm/Kconfig
@@ -351,6 +351,7 @@
select CPU_CACHE_V6
select CPU_CACHE_VIPT
select CPU_CP15_MMU
+ select CPU_HAS_ASID
select CPU_COPY_V6 if MMU
select CPU_TLB_V6 if MMU
@@ -376,6 +377,7 @@
select CPU_CACHE_V7
select CPU_CACHE_VIPT
select CPU_CP15_MMU
+ select CPU_HAS_ASID
select CPU_COPY_V6 if MMU
select CPU_TLB_V6 if MMU
@@ -498,6 +500,12 @@
endif
+config CPU_HAS_ASID
+ bool
+ help
+ This indicates whether the CPU has the ASID register; used to
+ tag TLB and possibly cache entries.
+
config CPU_CP15
bool
help
diff --git a/include/asm-arm/mmu.h b/include/asm-arm/mmu.h
index fe2a23b..53099d4 100644
--- a/include/asm-arm/mmu.h
+++ b/include/asm-arm/mmu.h
@@ -4,13 +4,13 @@
#ifdef CONFIG_MMU
typedef struct {
-#if __LINUX_ARM_ARCH__ >= 6
+#ifdef CONFIG_CPU_HAS_ASID
unsigned int id;
#endif
unsigned int kvm_seq;
} mm_context_t;
-#if __LINUX_ARM_ARCH__ >= 6
+#ifdef CONFIG_CPU_HAS_ASID
#define ASID(mm) ((mm)->context.id & 255)
#else
#define ASID(mm) (0)
diff --git a/include/asm-arm/mmu_context.h b/include/asm-arm/mmu_context.h
index 4981ad4..6913d02 100644
--- a/include/asm-arm/mmu_context.h
+++ b/include/asm-arm/mmu_context.h
@@ -20,7 +20,7 @@
void __check_kvm_seq(struct mm_struct *mm);
-#if __LINUX_ARM_ARCH__ >= 6
+#ifdef CONFIG_CPU_HAS_ASID
/*
* On ARMv6, we have the following structure in the Context ID: