#ifndef _ASM_M32R_SYSTEM_H #define _ASM_M32R_SYSTEM_H /* * This file is subject to the terms and conditions of the GNU General Public * License. See the file "COPYING" in the main directory of this archive * for more details. * * Copyright (C) 2001 Hiroyuki Kondo, Hirokazu Takata, and Hitoshi Yamamoto * Copyright (C) 2004, 2006 Hirokazu Takata <takata at linux-m32r.org> */ #include <linux/compiler.h> #include <asm/assembler.h> #ifdef __KERNEL__ /* * switch_to(prev, next) should switch from task `prev' to `next' * `prev' will never be the same as `next'. * * `next' and `prev' should be struct task_struct, but it isn't always defined */ #if defined(CONFIG_FRAME_POINTER) || \ !defined(CONFIG_SCHED_NO_NO_OMIT_FRAME_POINTER) #define M32R_PUSH_FP " push fp\n" #define M32R_POP_FP " pop fp\n" #else #define M32R_PUSH_FP "" #define M32R_POP_FP "" #endif #define switch_to(prev, next, last) do { \ __asm__ __volatile__ ( \ " seth lr, #high(1f) \n" \ " or3 lr, lr, #low(1f) \n" \ " st lr, @%4 ; store old LR \n" \ " ld lr, @%5 ; load new LR \n" \ M32R_PUSH_FP \ " st sp, @%2 ; store old SP \n" \ " ld sp, @%3 ; load new SP \n" \ " push %1 ; store `prev' on new stack \n" \ " jmp lr \n" \ " .fillinsn \n" \ "1: \n" \ " pop %0 ; restore `__last' from new stack \n" \ M32R_POP_FP \ : "=r" (last) \ : "0" (prev), \ "r" (&(prev->thread.sp)), "r" (&(next->thread.sp)), \ "r" (&(prev->thread.lr)), "r" (&(next->thread.lr)) \ : "memory", "lr" \ ); \ } while(0) /* Interrupt Control */ #if !defined(CONFIG_CHIP_M32102) && !defined(CONFIG_CHIP_M32104) #define local_irq_enable() \ __asm__ __volatile__ ("setpsw #0x40 -> nop": : :"memory") #define local_irq_disable() \ __asm__ __volatile__ ("clrpsw #0x40 -> nop": : :"memory") #else /* CONFIG_CHIP_M32102 || CONFIG_CHIP_M32104 */ static inline void local_irq_enable(void) { unsigned long tmpreg; __asm__ __volatile__( "mvfc %0, psw; \n\t" "or3 %0, %0, #0x0040; \n\t" "mvtc %0, psw; \n\t" : "=&r" (tmpreg) : : "cbit", "memory"); } static inline void local_irq_disable(void) { unsigned long tmpreg0, tmpreg1; __asm__ __volatile__( "ld24 %0, #0 ; Use 32-bit insn. \n\t" "mvfc %1, psw ; No interrupt can be accepted here. \n\t" "mvtc %0, psw \n\t" "and3 %0, %1, #0xffbf \n\t" "mvtc %0, psw \n\t" : "=&r" (tmpreg0), "=&r" (tmpreg1) : : "cbit", "memory"); } #endif /* CONFIG_CHIP_M32102 || CONFIG_CHIP_M32104 */ #define local_save_flags(x) \ __asm__ __volatile__("mvfc %0,psw" : "=r"(x) : /* no input */) #define local_irq_restore(x) \ __asm__ __volatile__("mvtc %0,psw" : /* no outputs */ \ : "r" (x) : "cbit", "memory") #if !(defined(CONFIG_CHIP_M32102) || defined(CONFIG_CHIP_M32104)) #define local_irq_save(x) \ __asm__ __volatile__( \ "mvfc %0, psw; \n\t" \ "clrpsw #0x40 -> nop; \n\t" \ : "=r" (x) : /* no input */ : "memory") #else /* CONFIG_CHIP_M32102 || CONFIG_CHIP_M32104 */ #define local_irq_save(x) \ ({ \ unsigned long tmpreg; \ __asm__ __volatile__( \ "ld24 %1, #0 \n\t" \ "mvfc %0, psw \n\t" \ "mvtc %1, psw \n\t" \ "and3 %1, %0, #0xffbf \n\t" \ "mvtc %1, psw \n\t" \ : "=r" (x), "=&r" (tmpreg) \ : : "cbit", "memory"); \ }) #endif /* CONFIG_CHIP_M32102 || CONFIG_CHIP_M32104 */ #define irqs_disabled() \ ({ \ unsigned long flags; \ local_save_flags(flags); \ !(flags & 0x40); \ }) #define nop() __asm__ __volatile__ ("nop" : : ) #define xchg(ptr,x) \ ((__typeof__(*(ptr)))__xchg((unsigned long)(x),(ptr),sizeof(*(ptr)))) #ifdef CONFIG_SMP extern void __xchg_called_with_bad_pointer(void); #endif #ifdef CONFIG_CHIP_M32700_TS1 #define DCACHE_CLEAR(reg0, reg1, addr) \ "seth "reg1", #high(dcache_dummy); \n\t" \ "or3 "reg1", "reg1", #low(dcache_dummy); \n\t" \ "lock "reg0", @"reg1"; \n\t" \ "add3 "reg0", "addr", #0x1000; \n\t" \ "ld "reg0", @"reg0"; \n\t" \ "add3 "reg0", "addr", #0x2000; \n\t" \ "ld "reg0", @"reg0"; \n\t" \ "unlock "reg0", @"reg1"; \n\t" /* FIXME: This workaround code cannot handle kernel modules * correctly under SMP environment. */ #else /* CONFIG_CHIP_M32700_TS1 */ #define DCACHE_CLEAR(reg0, reg1, addr) #endif /* CONFIG_CHIP_M32700_TS1 */ static __always_inline unsigned long __xchg(unsigned long x, volatile void * ptr, int size) { unsigned long flags; unsigned long tmp = 0; local_irq_save(flags); switch (size) { #ifndef CONFIG_SMP case 1: __asm__ __volatile__ ( "ldb %0, @%2 \n\t" "stb %1, @%2 \n\t" : "=&r" (tmp) : "r" (x), "r" (ptr) : "memory"); break; case 2: __asm__ __volatile__ ( "ldh %0, @%2 \n\t" "sth %1, @%2 \n\t" : "=&r" (tmp) : "r" (x), "r" (ptr) : "memory"); break; case 4: __asm__ __volatile__ ( "ld %0, @%2 \n\t" "st %1, @%2 \n\t" : "=&r" (tmp) : "r" (x), "r" (ptr) : "memory"); break; #else /* CONFIG_SMP */ case 4: __asm__ __volatile__ ( DCACHE_CLEAR("%0", "r4", "%2") "lock %0, @%2; \n\t" "unlock %1, @%2; \n\t" : "=&r" (tmp) : "r" (x), "r" (ptr) : "memory" #ifdef CONFIG_CHIP_M32700_TS1 , "r4" #endif /* CONFIG_CHIP_M32700_TS1 */ ); break; default: __xchg_called_with_bad_pointer(); #endif /* CONFIG_SMP */ } local_irq_restore(flags); return (tmp); } #define __HAVE_ARCH_CMPXCHG 1 static inline unsigned long __cmpxchg_u32(volatile unsigned int *p, unsigned int old, unsigned int new) { unsigned long flags; unsigned int retval; local_irq_save(flags); __asm__ __volatile__ ( DCACHE_CLEAR("%0", "r4", "%1") M32R_LOCK" %0, @%1; \n" " bne %0, %2, 1f; \n" M32R_UNLOCK" %3, @%1; \n" " bra 2f; \n" " .fillinsn \n" "1:" M32R_UNLOCK" %0, @%1; \n" " .fillinsn \n" "2:" : "=&r" (retval) : "r" (p), "r" (old), "r" (new) : "cbit", "memory" #ifdef CONFIG_CHIP_M32700_TS1 , "r4" #endif /* CONFIG_CHIP_M32700_TS1 */ ); local_irq_restore(flags); return retval; } /* This function doesn't exist, so you'll get a linker error if something tries to do an invalid cmpxchg(). */ extern void __cmpxchg_called_with_bad_pointer(void); static inline unsigned long __cmpxchg(volatile void *ptr, unsigned long old, unsigned long new, int size) { switch (size) { case 4: return __cmpxchg_u32(ptr, old, new); #if 0 /* we don't have __cmpxchg_u64 */ case 8: return __cmpxchg_u64(ptr, old, new); #endif /* 0 */ } __cmpxchg_called_with_bad_pointer(); return old; } #define cmpxchg(ptr,o,n) \ ({ \ __typeof__(*(ptr)) _o_ = (o); \ __typeof__(*(ptr)) _n_ = (n); \ (__typeof__(*(ptr))) __cmpxchg((ptr), (unsigned long)_o_, \ (unsigned long)_n_, sizeof(*(ptr))); \ }) #endif /* __KERNEL__ */ /* * Memory barrier. * * mb() prevents loads and stores being reordered across this point. * rmb() prevents loads being reordered across this point. * wmb() prevents stores being reordered across this point. */ #define mb() barrier() #define rmb() mb() #define wmb() mb() /** * read_barrier_depends - Flush all pending reads that subsequents reads * depend on. * * No data-dependent reads from memory-like regions are ever reordered * over this barrier. All reads preceding this primitive are guaranteed * to access memory (but not necessarily other CPUs' caches) before any * reads following this primitive that depend on the data return by * any of the preceding reads. This primitive is much lighter weight than * rmb() on most CPUs, and is never heavier weight than is * rmb(). * * These ordering constraints are respected by both the local CPU * and the compiler. * * Ordering is not guaranteed by anything other than these primitives, * not even by data dependencies. See the documentation for * memory_barrier() for examples and URLs to more information. * * For example, the following code would force ordering (the initial * value of "a" is zero, "b" is one, and "p" is "&a"): * * <programlisting> * CPU 0 CPU 1 * * b = 2; * memory_barrier(); * p = &b; q = p; * read_barrier_depends(); * d = *q; * </programlisting> * * * because the read of "*q" depends on the read of "p" and these * two reads are separated by a read_barrier_depends(). However, * the following code, with the same initial values for "a" and "b": * * <programlisting> * CPU 0 CPU 1 * * a = 2; * memory_barrier(); * b = 3; y = b; * read_barrier_depends(); * x = a; * </programlisting> * * does not enforce ordering, since there is no data dependency between * the read of "a" and the read of "b". Therefore, on some CPUs, such * as Alpha, "y" could be set to 3 and "x" to 0. Use rmb() * in cases like this where there are no data dependencies. **/ #define read_barrier_depends() do { } while (0) #ifdef CONFIG_SMP #define smp_mb() mb() #define smp_rmb() rmb() #define smp_wmb() wmb() #define smp_read_barrier_depends() read_barrier_depends() #define set_mb(var, value) do { (void) xchg(&var, value); } while (0) #else #define smp_mb() barrier() #define smp_rmb() barrier() #define smp_wmb() barrier() #define smp_read_barrier_depends() do { } while (0) #define set_mb(var, value) do { var = value; barrier(); } while (0) #endif #define arch_align_stack(x) (x) #endif /* _ASM_M32R_SYSTEM_H */