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-rw-r--r--arch/arm/include/asm/cachetype.h118
-rw-r--r--arch/arm/kernel/setup.c22
2 files changed, 59 insertions, 81 deletions
diff --git a/arch/arm/include/asm/cachetype.h b/arch/arm/include/asm/cachetype.h
index b52386bfd50..d3a4c2cb9f2 100644
--- a/arch/arm/include/asm/cachetype.h
+++ b/arch/arm/include/asm/cachetype.h
@@ -1,96 +1,52 @@
#ifndef __ASM_ARM_CACHETYPE_H
#define __ASM_ARM_CACHETYPE_H
-#include <asm/cputype.h>
+#define CACHEID_VIVT (1 << 0)
+#define CACHEID_VIPT_NONALIASING (1 << 1)
+#define CACHEID_VIPT_ALIASING (1 << 2)
+#define CACHEID_VIPT (CACHEID_VIPT_ALIASING|CACHEID_VIPT_NONALIASING)
+#define CACHEID_ASID_TAGGED (1 << 3)
-#define __cacheid_present(val) (val != read_cpuid_id())
-#define __cacheid_type_v7(val) ((val & (7 << 29)) == (4 << 29))
+extern unsigned int cacheid;
-#define __cacheid_vivt_prev7(val) ((val & (15 << 25)) != (14 << 25))
-#define __cacheid_vipt_prev7(val) ((val & (15 << 25)) == (14 << 25))
-#define __cacheid_vipt_nonaliasing_prev7(val) ((val & (15 << 25 | 1 << 23)) == (14 << 25))
-#define __cacheid_vipt_aliasing_prev7(val) ((val & (15 << 25 | 1 << 23)) == (14 << 25 | 1 << 23))
+#define cache_is_vivt() cacheid_is(CACHEID_VIVT)
+#define cache_is_vipt() cacheid_is(CACHEID_VIPT)
+#define cache_is_vipt_nonaliasing() cacheid_is(CACHEID_VIPT_NONALIASING)
+#define cache_is_vipt_aliasing() cacheid_is(CACHEID_VIPT_ALIASING)
+#define icache_is_vivt_asid_tagged() cacheid_is(CACHEID_ASID_TAGGED)
-#define __cacheid_vivt(val) (__cacheid_type_v7(val) ? 0 : __cacheid_vivt_prev7(val))
-#define __cacheid_vipt(val) (__cacheid_type_v7(val) ? 1 : __cacheid_vipt_prev7(val))
-#define __cacheid_vipt_nonaliasing(val) (__cacheid_type_v7(val) ? 1 : __cacheid_vipt_nonaliasing_prev7(val))
-#define __cacheid_vipt_aliasing(val) (__cacheid_type_v7(val) ? 0 : __cacheid_vipt_aliasing_prev7(val))
-#define __cacheid_vivt_asid_tagged_instr(val) (__cacheid_type_v7(val) ? ((val & (3 << 14)) == (1 << 14)) : 0)
-
-#if defined(CONFIG_CPU_CACHE_VIVT) && !defined(CONFIG_CPU_CACHE_VIPT)
/*
- * VIVT caches only
+ * __LINUX_ARM_ARCH__ is the minimum supported CPU architecture
+ * Mask out support which will never be present on newer CPUs.
+ * - v6+ is never VIVT
+ * - v7+ VIPT never aliases
*/
-#define cache_is_vivt() 1
-#define cache_is_vipt() 0
-#define cache_is_vipt_nonaliasing() 0
-#define cache_is_vipt_aliasing() 0
-#define icache_is_vivt_asid_tagged() 0
+#if __LINUX_ARM_ARCH__ >= 7
+#define __CACHEID_ARCH_MIN (CACHEID_VIPT_NONALIASING | CACHEID_ASID_TAGGED)
+#elif __LINUX_ARM_ARCH__ >= 6
+#define __CACHEID_ARCH_MIN (~CACHEID_VIVT)
+#else
+#define __CACHEID_ARCH_MIN (~0)
+#endif
-#elif !defined(CONFIG_CPU_CACHE_VIVT) && defined(CONFIG_CPU_CACHE_VIPT)
/*
- * VIPT caches only
+ * Mask out support which isn't configured
*/
-#define cache_is_vivt() 0
-#define cache_is_vipt() 1
-#define cache_is_vipt_nonaliasing() \
- ({ \
- unsigned int __val = read_cpuid_cachetype(); \
- __cacheid_vipt_nonaliasing(__val); \
- })
-
-#define cache_is_vipt_aliasing() \
- ({ \
- unsigned int __val = read_cpuid_cachetype(); \
- __cacheid_vipt_aliasing(__val); \
- })
-
-#define icache_is_vivt_asid_tagged() \
- ({ \
- unsigned int __val = read_cpuid_cachetype(); \
- __cacheid_vivt_asid_tagged_instr(__val); \
- })
-
+#if defined(CONFIG_CPU_CACHE_VIVT) && !defined(CONFIG_CPU_CACHE_VIPT)
+#define __CACHEID_ALWAYS (CACHEID_VIVT)
+#define __CACHEID_NEVER (~CACHEID_VIVT)
+#elif !defined(CONFIG_CPU_CACHE_VIVT) && defined(CONFIG_CPU_CACHE_VIPT)
+#define __CACHEID_ALWAYS (0)
+#define __CACHEID_NEVER (CACHEID_VIVT)
#else
-/*
- * VIVT or VIPT caches. Note that this is unreliable since ARM926
- * and V6 CPUs satisfy the "(val & (15 << 25)) == (14 << 25)" test.
- * There's no way to tell from the CacheType register what type (!)
- * the cache is.
- */
-#define cache_is_vivt() \
- ({ \
- unsigned int __val = read_cpuid_cachetype(); \
- (!__cacheid_present(__val)) || __cacheid_vivt(__val); \
- })
-
-#define cache_is_vipt() \
- ({ \
- unsigned int __val = read_cpuid_cachetype(); \
- __cacheid_present(__val) && __cacheid_vipt(__val); \
- })
-
-#define cache_is_vipt_nonaliasing() \
- ({ \
- unsigned int __val = read_cpuid_cachetype(); \
- __cacheid_present(__val) && \
- __cacheid_vipt_nonaliasing(__val); \
- })
-
-#define cache_is_vipt_aliasing() \
- ({ \
- unsigned int __val = read_cpuid_cachetype(); \
- __cacheid_present(__val) && \
- __cacheid_vipt_aliasing(__val); \
- })
-
-#define icache_is_vivt_asid_tagged() \
- ({ \
- unsigned int __val = read_cpuid_cachetype(); \
- __cacheid_present(__val) && \
- __cacheid_vivt_asid_tagged_instr(__val); \
- })
-
+#define __CACHEID_ALWAYS (0)
+#define __CACHEID_NEVER (0)
#endif
+static inline unsigned int __attribute__((pure)) cacheid_is(unsigned int mask)
+{
+ return (__CACHEID_ALWAYS & mask) |
+ (~__CACHEID_NEVER & __CACHEID_ARCH_MIN & mask & cacheid);
+}
+
#endif
diff --git a/arch/arm/kernel/setup.c b/arch/arm/kernel/setup.c
index 1939c904dae..5b121d81f9e 100644
--- a/arch/arm/kernel/setup.c
+++ b/arch/arm/kernel/setup.c
@@ -67,6 +67,8 @@ unsigned int processor_id;
EXPORT_SYMBOL(processor_id);
unsigned int __machine_arch_type;
EXPORT_SYMBOL(__machine_arch_type);
+unsigned int cacheid;
+EXPORT_SYMBOL(cacheid);
unsigned int __atags_pointer __initdata;
@@ -229,6 +231,25 @@ int cpu_architecture(void)
return cpu_arch;
}
+static void __init cacheid_init(void)
+{
+ unsigned int cachetype = read_cpuid_cachetype();
+ unsigned int arch = cpu_architecture();
+
+ if (arch >= CPU_ARCH_ARMv7) {
+ cacheid = CACHEID_VIPT_NONALIASING;
+ if ((cachetype & (3 << 14)) == 1 << 14)
+ cacheid |= CACHEID_ASID_TAGGED;
+ } else if (arch >= CPU_ARCH_ARMv6) {
+ if (cachetype & (1 << 23))
+ cacheid = CACHEID_VIPT_ALIASING;
+ else
+ cacheid = CACHEID_VIPT_NONALIASING;
+ } else {
+ cacheid = CACHEID_VIVT;
+ }
+}
+
/*
* These functions re-use the assembly code in head.S, which
* already provide the required functionality.
@@ -278,6 +299,7 @@ static void __init setup_processor(void)
elf_hwcap &= ~HWCAP_THUMB;
#endif
+ cacheid_init();
cpu_proc_init();
}