diff options
Diffstat (limited to 'arch/arm/include/asm')
| -rw-r--r-- | arch/arm/include/asm/assembler.h | 13 | ||||
| -rw-r--r-- | arch/arm/include/asm/atomic.h | 61 | ||||
| -rw-r--r-- | arch/arm/include/asm/cache.h | 16 | ||||
| -rw-r--r-- | arch/arm/include/asm/flat.h | 3 | ||||
| -rw-r--r-- | arch/arm/include/asm/page.h | 7 | ||||
| -rw-r--r-- | arch/arm/include/asm/system.h | 176 |
6 files changed, 257 insertions, 19 deletions
diff --git a/arch/arm/include/asm/assembler.h b/arch/arm/include/asm/assembler.h index 6116e4893c0..15f8a092b70 100644 --- a/arch/arm/include/asm/assembler.h +++ b/arch/arm/include/asm/assembler.h @@ -114,3 +114,16 @@ .align 3; \ .long 9999b,9001f; \ .previous + +/* + * SMP data memory barrier + */ + .macro smp_dmb +#ifdef CONFIG_SMP +#if __LINUX_ARM_ARCH__ >= 7 + dmb +#elif __LINUX_ARM_ARCH__ == 6 + mcr p15, 0, r0, c7, c10, 5 @ dmb +#endif +#endif + .endm diff --git a/arch/arm/include/asm/atomic.h b/arch/arm/include/asm/atomic.h index ee99723b3a6..16b52f39798 100644 --- a/arch/arm/include/asm/atomic.h +++ b/arch/arm/include/asm/atomic.h @@ -44,11 +44,29 @@ static inline void atomic_set(atomic_t *v, int i) : "cc"); } +static inline void atomic_add(int i, atomic_t *v) +{ + unsigned long tmp; + int result; + + __asm__ __volatile__("@ atomic_add\n" +"1: ldrex %0, [%2]\n" +" add %0, %0, %3\n" +" strex %1, %0, [%2]\n" +" teq %1, #0\n" +" bne 1b" + : "=&r" (result), "=&r" (tmp) + : "r" (&v->counter), "Ir" (i) + : "cc"); +} + static inline int atomic_add_return(int i, atomic_t *v) { unsigned long tmp; int result; + smp_mb(); + __asm__ __volatile__("@ atomic_add_return\n" "1: ldrex %0, [%2]\n" " add %0, %0, %3\n" @@ -59,14 +77,34 @@ static inline int atomic_add_return(int i, atomic_t *v) : "r" (&v->counter), "Ir" (i) : "cc"); + smp_mb(); + return result; } +static inline void atomic_sub(int i, atomic_t *v) +{ + unsigned long tmp; + int result; + + __asm__ __volatile__("@ atomic_sub\n" +"1: ldrex %0, [%2]\n" +" sub %0, %0, %3\n" +" strex %1, %0, [%2]\n" +" teq %1, #0\n" +" bne 1b" + : "=&r" (result), "=&r" (tmp) + : "r" (&v->counter), "Ir" (i) + : "cc"); +} + static inline int atomic_sub_return(int i, atomic_t *v) { unsigned long tmp; int result; + smp_mb(); + __asm__ __volatile__("@ atomic_sub_return\n" "1: ldrex %0, [%2]\n" " sub %0, %0, %3\n" @@ -77,6 +115,8 @@ static inline int atomic_sub_return(int i, atomic_t *v) : "r" (&v->counter), "Ir" (i) : "cc"); + smp_mb(); + return result; } @@ -84,6 +124,8 @@ static inline int atomic_cmpxchg(atomic_t *ptr, int old, int new) { unsigned long oldval, res; + smp_mb(); + do { __asm__ __volatile__("@ atomic_cmpxchg\n" "ldrex %1, [%2]\n" @@ -95,6 +137,8 @@ static inline int atomic_cmpxchg(atomic_t *ptr, int old, int new) : "cc"); } while (res); + smp_mb(); + return oldval; } @@ -135,6 +179,7 @@ static inline int atomic_add_return(int i, atomic_t *v) return val; } +#define atomic_add(i, v) (void) atomic_add_return(i, v) static inline int atomic_sub_return(int i, atomic_t *v) { @@ -148,6 +193,7 @@ static inline int atomic_sub_return(int i, atomic_t *v) return val; } +#define atomic_sub(i, v) (void) atomic_sub_return(i, v) static inline int atomic_cmpxchg(atomic_t *v, int old, int new) { @@ -187,10 +233,8 @@ static inline int atomic_add_unless(atomic_t *v, int a, int u) } #define atomic_inc_not_zero(v) atomic_add_unless((v), 1, 0) -#define atomic_add(i, v) (void) atomic_add_return(i, v) -#define atomic_inc(v) (void) atomic_add_return(1, v) -#define atomic_sub(i, v) (void) atomic_sub_return(i, v) -#define atomic_dec(v) (void) atomic_sub_return(1, v) +#define atomic_inc(v) atomic_add(1, v) +#define atomic_dec(v) atomic_sub(1, v) #define atomic_inc_and_test(v) (atomic_add_return(1, v) == 0) #define atomic_dec_and_test(v) (atomic_sub_return(1, v) == 0) @@ -200,11 +244,10 @@ static inline int atomic_add_unless(atomic_t *v, int a, int u) #define atomic_add_negative(i,v) (atomic_add_return(i, v) < 0) -/* Atomic operations are already serializing on ARM */ -#define smp_mb__before_atomic_dec() barrier() -#define smp_mb__after_atomic_dec() barrier() -#define smp_mb__before_atomic_inc() barrier() -#define smp_mb__after_atomic_inc() barrier() +#define smp_mb__before_atomic_dec() smp_mb() +#define smp_mb__after_atomic_dec() smp_mb() +#define smp_mb__before_atomic_inc() smp_mb() +#define smp_mb__after_atomic_inc() smp_mb() #include <asm-generic/atomic.h> #endif diff --git a/arch/arm/include/asm/cache.h b/arch/arm/include/asm/cache.h index cb7a9e97fd7..feaa75f0013 100644 --- a/arch/arm/include/asm/cache.h +++ b/arch/arm/include/asm/cache.h @@ -7,4 +7,20 @@ #define L1_CACHE_SHIFT 5 #define L1_CACHE_BYTES (1 << L1_CACHE_SHIFT) +/* + * Memory returned by kmalloc() may be used for DMA, so we must make + * sure that all such allocations are cache aligned. Otherwise, + * unrelated code may cause parts of the buffer to be read into the + * cache before the transfer is done, causing old data to be seen by + * the CPU. + */ +#define ARCH_KMALLOC_MINALIGN L1_CACHE_BYTES + +/* + * With EABI on ARMv5 and above we must have 64-bit aligned slab pointers. + */ +#if defined(CONFIG_AEABI) && (__LINUX_ARM_ARCH__ >= 5) +#define ARCH_SLAB_MINALIGN 8 +#endif + #endif diff --git a/arch/arm/include/asm/flat.h b/arch/arm/include/asm/flat.h index 1d77e51907f..59426a4595c 100644 --- a/arch/arm/include/asm/flat.h +++ b/arch/arm/include/asm/flat.h @@ -5,9 +5,6 @@ #ifndef __ARM_FLAT_H__ #define __ARM_FLAT_H__ -/* An odd number of words will be pushed after this alignment, so - deliberately misalign the value. */ -#define flat_stack_align(sp) sp = (void *)(((unsigned long)(sp) - 4) | 4) #define flat_argvp_envp_on_stack() 1 #define flat_old_ram_flag(flags) (flags) #define flat_reloc_valid(reloc, size) ((reloc) <= (size)) diff --git a/arch/arm/include/asm/page.h b/arch/arm/include/asm/page.h index e6eb8a67b80..7b522770f29 100644 --- a/arch/arm/include/asm/page.h +++ b/arch/arm/include/asm/page.h @@ -202,13 +202,6 @@ typedef struct page *pgtable_t; (((current->personality & READ_IMPLIES_EXEC) ? VM_EXEC : 0) | \ VM_READ | VM_WRITE | VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC) -/* - * With EABI on ARMv5 and above we must have 64-bit aligned slab pointers. - */ -#if defined(CONFIG_AEABI) && (__LINUX_ARM_ARCH__ >= 5) -#define ARCH_SLAB_MINALIGN 8 -#endif - #include <asm-generic/page.h> #endif diff --git a/arch/arm/include/asm/system.h b/arch/arm/include/asm/system.h index bd4dc8ed53d..d65b2f5bf41 100644 --- a/arch/arm/include/asm/system.h +++ b/arch/arm/include/asm/system.h @@ -248,6 +248,8 @@ static inline unsigned long __xchg(unsigned long x, volatile void *ptr, int size unsigned int tmp; #endif + smp_mb(); + switch (size) { #if __LINUX_ARM_ARCH__ >= 6 case 1: @@ -307,6 +309,7 @@ static inline unsigned long __xchg(unsigned long x, volatile void *ptr, int size __bad_xchg(ptr, size), ret = 0; break; } + smp_mb(); return ret; } @@ -316,6 +319,12 @@ extern void enable_hlt(void); #include <asm-generic/cmpxchg-local.h> +#if __LINUX_ARM_ARCH__ < 6 + +#ifdef CONFIG_SMP +#error "SMP is not supported on this platform" +#endif + /* * cmpxchg_local and cmpxchg64_local are atomic wrt current CPU. Always make * them available. @@ -329,6 +338,173 @@ extern void enable_hlt(void); #include <asm-generic/cmpxchg.h> #endif +#else /* __LINUX_ARM_ARCH__ >= 6 */ + +extern void __bad_cmpxchg(volatile void *ptr, int size); + +/* + * cmpxchg only support 32-bits operands on ARMv6. + */ + +static inline unsigned long __cmpxchg(volatile void *ptr, unsigned long old, + unsigned long new, int size) +{ + unsigned long oldval, res; + + switch (size) { +#ifdef CONFIG_CPU_32v6K + case 1: + do { + asm volatile("@ __cmpxchg1\n" + " ldrexb %1, [%2]\n" + " mov %0, #0\n" + " teq %1, %3\n" + " strexbeq %0, %4, [%2]\n" + : "=&r" (res), "=&r" (oldval) + : "r" (ptr), "Ir" (old), "r" (new) + : "memory", "cc"); + } while (res); + break; + case 2: + do { + asm volatile("@ __cmpxchg1\n" + " ldrexh %1, [%2]\n" + " mov %0, #0\n" + " teq %1, %3\n" + " strexheq %0, %4, [%2]\n" + : "=&r" (res), "=&r" (oldval) + : "r" (ptr), "Ir" (old), "r" (new) + : "memory", "cc"); + } while (res); + break; +#endif /* CONFIG_CPU_32v6K */ + case 4: + do { + asm volatile("@ __cmpxchg4\n" + " ldrex %1, [%2]\n" + " mov %0, #0\n" + " teq %1, %3\n" + " strexeq %0, %4, [%2]\n" + : "=&r" (res), "=&r" (oldval) + : "r" (ptr), "Ir" (old), "r" (new) + : "memory", "cc"); + } while (res); + break; + default: + __bad_cmpxchg(ptr, size); + oldval = 0; + } + + return oldval; +} + +static inline unsigned long __cmpxchg_mb(volatile void *ptr, unsigned long old, + unsigned long new, int size) +{ + unsigned long ret; + + smp_mb(); + ret = __cmpxchg(ptr, old, new, size); + smp_mb(); + + return ret; +} + +#define cmpxchg(ptr,o,n) \ + ((__typeof__(*(ptr)))__cmpxchg_mb((ptr), \ + (unsigned long)(o), \ + (unsigned long)(n), \ + sizeof(*(ptr)))) + +static inline unsigned long __cmpxchg_local(volatile void *ptr, + unsigned long old, + unsigned long new, int size) +{ + unsigned long ret; + + switch (size) { +#ifndef CONFIG_CPU_32v6K + case 1: + case 2: + ret = __cmpxchg_local_generic(ptr, old, new, size); + break; +#endif /* !CONFIG_CPU_32v6K */ + default: + ret = __cmpxchg(ptr, old, new, size); + } + + return ret; +} + +#define cmpxchg_local(ptr,o,n) \ + ((__typeof__(*(ptr)))__cmpxchg_local((ptr), \ + (unsigned long)(o), \ + (unsigned long)(n), \ + sizeof(*(ptr)))) + +#ifdef CONFIG_CPU_32v6K + +/* + * Note : ARMv7-M (currently unsupported by Linux) does not support + * ldrexd/strexd. If ARMv7-M is ever supported by the Linux kernel, it should + * not be allowed to use __cmpxchg64. + */ +static inline unsigned long long __cmpxchg64(volatile void *ptr, + unsigned long long old, + unsigned long long new) +{ + register unsigned long long oldval asm("r0"); + register unsigned long long __old asm("r2") = old; + register unsigned long long __new asm("r4") = new; + unsigned long res; + + do { + asm volatile( + " @ __cmpxchg8\n" + " ldrexd %1, %H1, [%2]\n" + " mov %0, #0\n" + " teq %1, %3\n" + " teqeq %H1, %H3\n" + " strexdeq %0, %4, %H4, [%2]\n" + : "=&r" (res), "=&r" (oldval) + : "r" (ptr), "Ir" (__old), "r" (__new) + : "memory", "cc"); + } while (res); + + return oldval; +} + +static inline unsigned long long __cmpxchg64_mb(volatile void *ptr, + unsigned long long old, + unsigned long long new) +{ + unsigned long long ret; + + smp_mb(); + ret = __cmpxchg64(ptr, old, new); + smp_mb(); + + return ret; +} + +#define cmpxchg64(ptr,o,n) \ + ((__typeof__(*(ptr)))__cmpxchg64_mb((ptr), \ + (unsigned long long)(o), \ + (unsigned long long)(n))) + +#define cmpxchg64_local(ptr,o,n) \ + ((__typeof__(*(ptr)))__cmpxchg64((ptr), \ + (unsigned long long)(o), \ + (unsigned long long)(n))) + +#else /* !CONFIG_CPU_32v6K */ + +#define cmpxchg64_local(ptr, o, n) __cmpxchg64_local_generic((ptr), (o), (n)) + +#endif /* CONFIG_CPU_32v6K */ + +#endif /* __LINUX_ARM_ARCH__ >= 6 */ + #endif /* __ASSEMBLY__ */ #define arch_align_stack(x) (x) |