From: Sam Ravnborg Date: Mon, 26 Dec 2011 19:57:22 +0000 (+0100) Subject: sparc32: drop unused atomic24 support X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=348738afe530cc3a7306bbd3d1ccd322f9638f32;p=mv-sheeva.git sparc32: drop unused atomic24 support atomic24 support was used to semaphores in the past - but is no longer used. Signed-off-by: Sam Ravnborg Signed-off-by: David S. Miller --- diff --git a/arch/sparc/include/asm/atomic_32.h b/arch/sparc/include/asm/atomic_32.h index 5c3c8b69884..534832f5b35 100644 --- a/arch/sparc/include/asm/atomic_32.h +++ b/arch/sparc/include/asm/atomic_32.h @@ -52,106 +52,6 @@ extern void atomic_set(atomic_t *, int); #define atomic_dec_and_test(v) (atomic_dec_return(v) == 0) #define atomic_sub_and_test(i, v) (atomic_sub_return(i, v) == 0) - -/* This is the old 24-bit implementation. It's still used internally - * by some sparc-specific code, notably the semaphore implementation. - */ -typedef struct { volatile int counter; } atomic24_t; - -#ifndef CONFIG_SMP - -#define ATOMIC24_INIT(i) { (i) } -#define atomic24_read(v) ((v)->counter) -#define atomic24_set(v, i) (((v)->counter) = i) - -#else -/* We do the bulk of the actual work out of line in two common - * routines in assembler, see arch/sparc/lib/atomic.S for the - * "fun" details. - * - * For SMP the trick is you embed the spin lock byte within - * the word, use the low byte so signedness is easily retained - * via a quick arithmetic shift. It looks like this: - * - * ---------------------------------------- - * | signed 24-bit counter value | lock | atomic_t - * ---------------------------------------- - * 31 8 7 0 - */ - -#define ATOMIC24_INIT(i) { ((i) << 8) } - -static inline int atomic24_read(const atomic24_t *v) -{ - int ret = v->counter; - - while(ret & 0xff) - ret = v->counter; - - return ret >> 8; -} - -#define atomic24_set(v, i) (((v)->counter) = ((i) << 8)) -#endif - -static inline int __atomic24_add(int i, atomic24_t *v) -{ - register volatile int *ptr asm("g1"); - register int increment asm("g2"); - register int tmp1 asm("g3"); - register int tmp2 asm("g4"); - register int tmp3 asm("g7"); - - ptr = &v->counter; - increment = i; - - __asm__ __volatile__( - "mov %%o7, %%g4\n\t" - "call ___atomic24_add\n\t" - " add %%o7, 8, %%o7\n" - : "=&r" (increment), "=r" (tmp1), "=r" (tmp2), "=r" (tmp3) - : "0" (increment), "r" (ptr) - : "memory", "cc"); - - return increment; -} - -static inline int __atomic24_sub(int i, atomic24_t *v) -{ - register volatile int *ptr asm("g1"); - register int increment asm("g2"); - register int tmp1 asm("g3"); - register int tmp2 asm("g4"); - register int tmp3 asm("g7"); - - ptr = &v->counter; - increment = i; - - __asm__ __volatile__( - "mov %%o7, %%g4\n\t" - "call ___atomic24_sub\n\t" - " add %%o7, 8, %%o7\n" - : "=&r" (increment), "=r" (tmp1), "=r" (tmp2), "=r" (tmp3) - : "0" (increment), "r" (ptr) - : "memory", "cc"); - - return increment; -} - -#define atomic24_add(i, v) ((void)__atomic24_add((i), (v))) -#define atomic24_sub(i, v) ((void)__atomic24_sub((i), (v))) - -#define atomic24_dec_return(v) __atomic24_sub(1, (v)) -#define atomic24_inc_return(v) __atomic24_add(1, (v)) - -#define atomic24_sub_and_test(i, v) (__atomic24_sub((i), (v)) == 0) -#define atomic24_dec_and_test(v) (__atomic24_sub(1, (v)) == 0) - -#define atomic24_inc(v) ((void)__atomic24_add(1, (v))) -#define atomic24_dec(v) ((void)__atomic24_sub(1, (v))) - -#define atomic24_add_negative(i, v) (__atomic24_add((i), (v)) < 0) - /* Atomic operations are already serializing */ #define smp_mb__before_atomic_dec() barrier() #define smp_mb__after_atomic_dec() barrier() diff --git a/arch/sparc/lib/atomic_32.S b/arch/sparc/lib/atomic_32.S index 178cbb8ae1b..eb6c7359cbd 100644 --- a/arch/sparc/lib/atomic_32.S +++ b/arch/sparc/lib/atomic_32.S @@ -40,60 +40,5 @@ ___xchg32_sun4md: mov %g4, %o7 #endif - /* Read asm-sparc/atomic.h carefully to understand how this works for SMP. - * Really, some things here for SMP are overly clever, go read the header. - */ - .globl ___atomic24_add -___atomic24_add: - rd %psr, %g3 ! Keep the code small, old way was stupid - nop; nop; nop; ! Let the bits set - or %g3, PSR_PIL, %g7 ! Disable interrupts - wr %g7, 0x0, %psr ! Set %psr - nop; nop; nop; ! Let the bits set -#ifdef CONFIG_SMP -1: ldstub [%g1 + 3], %g7 ! Spin on the byte lock for SMP. - orcc %g7, 0x0, %g0 ! Did we get it? - bne 1b ! Nope... - ld [%g1], %g7 ! Load locked atomic24_t - sra %g7, 8, %g7 ! Get signed 24-bit integer - add %g7, %g2, %g2 ! Add in argument - sll %g2, 8, %g7 ! Transpose back to atomic24_t - st %g7, [%g1] ! Clever: This releases the lock as well. -#else - ld [%g1], %g7 ! Load locked atomic24_t - add %g7, %g2, %g2 ! Add in argument - st %g2, [%g1] ! Store it back -#endif - wr %g3, 0x0, %psr ! Restore original PSR_PIL - nop; nop; nop; ! Let the bits set - jmpl %o7, %g0 ! NOTE: not + 8, see callers in atomic.h - mov %g4, %o7 ! Restore %o7 - - .globl ___atomic24_sub -___atomic24_sub: - rd %psr, %g3 ! Keep the code small, old way was stupid - nop; nop; nop; ! Let the bits set - or %g3, PSR_PIL, %g7 ! Disable interrupts - wr %g7, 0x0, %psr ! Set %psr - nop; nop; nop; ! Let the bits set -#ifdef CONFIG_SMP -1: ldstub [%g1 + 3], %g7 ! Spin on the byte lock for SMP. - orcc %g7, 0x0, %g0 ! Did we get it? - bne 1b ! Nope... - ld [%g1], %g7 ! Load locked atomic24_t - sra %g7, 8, %g7 ! Get signed 24-bit integer - sub %g7, %g2, %g2 ! Subtract argument - sll %g2, 8, %g7 ! Transpose back to atomic24_t - st %g7, [%g1] ! Clever: This releases the lock as well -#else - ld [%g1], %g7 ! Load locked atomic24_t - sub %g7, %g2, %g2 ! Subtract argument - st %g2, [%g1] ! Store it back -#endif - wr %g3, 0x0, %psr ! Restore original PSR_PIL - nop; nop; nop; ! Let the bits set - jmpl %o7, %g0 ! NOTE: not + 8, see callers in atomic.h - mov %g4, %o7 ! Restore %o7 - .globl __atomic_end __atomic_end: diff --git a/arch/sparc/lib/ksyms.c b/arch/sparc/lib/ksyms.c index 1b30bb3bfdb..f73c2240fe6 100644 --- a/arch/sparc/lib/ksyms.c +++ b/arch/sparc/lib/ksyms.c @@ -62,8 +62,6 @@ extern void ___rw_read_enter(void); extern void ___rw_read_try(void); extern void ___rw_read_exit(void); extern void ___rw_write_enter(void); -extern void ___atomic24_add(void); -extern void ___atomic24_sub(void); /* Alias functions whose names begin with "." and export the aliases. * The module references will be fixed up by module_frob_arch_sections. @@ -97,10 +95,6 @@ EXPORT_SYMBOL(___rw_read_exit); EXPORT_SYMBOL(___rw_write_enter); #endif -/* Atomic operations. */ -EXPORT_SYMBOL(___atomic24_add); -EXPORT_SYMBOL(___atomic24_sub); - EXPORT_SYMBOL(__ashrdi3); EXPORT_SYMBOL(__ashldi3); EXPORT_SYMBOL(__lshrdi3);