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-rw-r--r--arch/sh/include/asm/system.h275
1 files changed, 275 insertions, 0 deletions
diff --git a/arch/sh/include/asm/system.h b/arch/sh/include/asm/system.h
new file mode 100644
index 0000000..a62c422
--- /dev/null
+++ b/arch/sh/include/asm/system.h
@@ -0,0 +1,275 @@
+#ifndef __ASM_SH_SYSTEM_H
+#define __ASM_SH_SYSTEM_H
+
+/*
+ * Copyright (C) 1999, 2000 Niibe Yutaka & Kaz Kojima
+ * Copyright (C) 2002 Paul Mundt
+ *
+ * from linux kernel code.
+ */
+
+#include <linux/irqflags.h>
+#include <asm/types.h>
+
+/*
+ * switch_to() should switch tasks to task nr n, first
+ */
+
+#define switch_to(prev, next, last) do { \
+ struct task_struct *__last; \
+ register unsigned long *__ts1 __asm__ ("r1") = &prev->thread.sp; \
+ register unsigned long *__ts2 __asm__ ("r2") = &prev->thread.pc; \
+ register unsigned long *__ts4 __asm__ ("r4") = (unsigned long *)prev; \
+ register unsigned long *__ts5 __asm__ ("r5") = (unsigned long *)next; \
+ register unsigned long *__ts6 __asm__ ("r6") = &next->thread.sp; \
+ register unsigned long __ts7 __asm__ ("r7") = next->thread.pc; \
+ __asm__ __volatile__ (".balign 4\n\t" \
+ "stc.l gbr, @-r15\n\t" \
+ "sts.l pr, @-r15\n\t" \
+ "mov.l r8, @-r15\n\t" \
+ "mov.l r9, @-r15\n\t" \
+ "mov.l r10, @-r15\n\t" \
+ "mov.l r11, @-r15\n\t" \
+ "mov.l r12, @-r15\n\t" \
+ "mov.l r13, @-r15\n\t" \
+ "mov.l r14, @-r15\n\t" \
+ "mov.l r15, @r1 ! save SP\n\t" \
+ "mov.l @r6, r15 ! change to new stack\n\t" \
+ "mova 1f, %0\n\t" \
+ "mov.l %0, @r2 ! save PC\n\t" \
+ "mov.l 2f, %0\n\t" \
+ "jmp @%0 ! call __switch_to\n\t" \
+ " lds r7, pr ! with return to new PC\n\t" \
+ ".balign 4\n" \
+ "2:\n\t" \
+ ".long __switch_to\n" \
+ "1:\n\t" \
+ "mov.l @r15+, r14\n\t" \
+ "mov.l @r15+, r13\n\t" \
+ "mov.l @r15+, r12\n\t" \
+ "mov.l @r15+, r11\n\t" \
+ "mov.l @r15+, r10\n\t" \
+ "mov.l @r15+, r9\n\t" \
+ "mov.l @r15+, r8\n\t" \
+ "lds.l @r15+, pr\n\t" \
+ "ldc.l @r15+, gbr\n\t" \
+ : "=z" (__last) \
+ : "r" (__ts1), "r" (__ts2), "r" (__ts4), \
+ "r" (__ts5), "r" (__ts6), "r" (__ts7) \
+ : "r3", "t"); \
+ last = __last; \
+} while (0)
+
+/*
+ * On SMP systems, when the scheduler does migration-cost autodetection,
+ * it needs a way to flush as much of the CPU's caches as possible.
+ *
+ * TODO: fill this in!
+ */
+static inline void sched_cacheflush(void)
+{
+}
+
+#ifdef CONFIG_CPU_SH4A
+#define __icbi() \
+{ \
+ unsigned long __addr; \
+ __addr = 0xa8000000; \
+ __asm__ __volatile__( \
+ "icbi %0\n\t" \
+ : /* no output */ \
+ : "m" (__m(__addr))); \
+}
+#endif
+
+static inline unsigned long tas(volatile int *m)
+{
+ unsigned long retval;
+
+ __asm__ __volatile__ ("tas.b @%1\n\t"
+ "movt %0"
+ : "=r" (retval): "r" (m): "t", "memory");
+ return retval;
+}
+
+/*
+ * A brief note on ctrl_barrier(), the control register write barrier.
+ *
+ * Legacy SH cores typically require a sequence of 8 nops after
+ * modification of a control register in order for the changes to take
+ * effect. On newer cores (like the sh4a and sh5) this is accomplished
+ * with icbi.
+ *
+ * Also note that on sh4a in the icbi case we can forego a synco for the
+ * write barrier, as it's not necessary for control registers.
+ *
+ * Historically we have only done this type of barrier for the MMUCR, but
+ * it's also necessary for the CCR, so we make it generic here instead.
+ */
+#ifdef CONFIG_CPU_SH4A
+#define mb() __asm__ __volatile__ ("synco": : :"memory")
+#define rmb() mb()
+#define wmb() __asm__ __volatile__ ("synco": : :"memory")
+#define ctrl_barrier() __icbi()
+#define read_barrier_depends() do { } while(0)
+#else
+#define mb() __asm__ __volatile__ ("": : :"memory")
+#define rmb() mb()
+#define wmb() __asm__ __volatile__ ("": : :"memory")
+#define ctrl_barrier() __asm__ __volatile__ ("nop;nop;nop;nop;nop;nop;nop;nop")
+#define read_barrier_depends() do { } while(0)
+#endif
+
+#ifdef CONFIG_SMP
+#define smp_mb() mb()
+#define smp_rmb() rmb()
+#define smp_wmb() wmb()
+#define smp_read_barrier_depends() read_barrier_depends()
+#else
+#define smp_mb() barrier()
+#define smp_rmb() barrier()
+#define smp_wmb() barrier()
+#define smp_read_barrier_depends() do { } while(0)
+#endif
+
+#define set_mb(var, value) do { xchg(&var, value); } while (0)
+
+/*
+ * Jump to P2 area.
+ * When handling TLB or caches, we need to do it from P2 area.
+ */
+#define jump_to_P2() \
+do { \
+ unsigned long __dummy; \
+ __asm__ __volatile__( \
+ "mov.l 1f, %0\n\t" \
+ "or %1, %0\n\t" \
+ "jmp @%0\n\t" \
+ " nop\n\t" \
+ ".balign 4\n" \
+ "1: .long 2f\n" \
+ "2:" \
+ : "=&r" (__dummy) \
+ : "r" (0x20000000)); \
+} while (0)
+
+/*
+ * Back to P1 area.
+ */
+#define back_to_P1() \
+do { \
+ unsigned long __dummy; \
+ ctrl_barrier(); \
+ __asm__ __volatile__( \
+ "mov.l 1f, %0\n\t" \
+ "jmp @%0\n\t" \
+ " nop\n\t" \
+ ".balign 4\n" \
+ "1: .long 2f\n" \
+ "2:" \
+ : "=&r" (__dummy)); \
+} while (0)
+
+static inline unsigned long xchg_u32(volatile u32 *m, unsigned long val)
+{
+ unsigned long flags, retval;
+
+ local_irq_save(flags);
+ retval = *m;
+ *m = val;
+ local_irq_restore(flags);
+ return retval;
+}
+
+static inline unsigned long xchg_u8(volatile u8 *m, unsigned long val)
+{
+ unsigned long flags, retval;
+
+ local_irq_save(flags);
+ retval = *m;
+ *m = val & 0xff;
+ local_irq_restore(flags);
+ return retval;
+}
+
+extern void __xchg_called_with_bad_pointer(void);
+
+#define __xchg(ptr, x, size) \
+({ \
+ unsigned long __xchg__res; \
+ volatile void *__xchg_ptr = (ptr); \
+ switch (size) { \
+ case 4: \
+ __xchg__res = xchg_u32(__xchg_ptr, x); \
+ break; \
+ case 1: \
+ __xchg__res = xchg_u8(__xchg_ptr, x); \
+ break; \
+ default: \
+ __xchg_called_with_bad_pointer(); \
+ __xchg__res = x; \
+ break; \
+ } \
+ \
+ __xchg__res; \
+})
+
+#define xchg(ptr,x) \
+ ((__typeof__(*(ptr)))__xchg((ptr),(unsigned long)(x), sizeof(*(ptr))))
+
+static inline unsigned long __cmpxchg_u32(volatile int * m, unsigned long old,
+ unsigned long new)
+{
+ __u32 retval;
+ unsigned long flags;
+
+ local_irq_save(flags);
+ retval = *m;
+ if (retval == old)
+ *m = new;
+ local_irq_restore(flags); /* implies memory barrier */
+ 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);
+
+#define __HAVE_ARCH_CMPXCHG 1
+
+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);
+ }
+ __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))); \
+ })
+
+extern void *set_exception_table_vec(unsigned int vec, void *handler);
+
+static inline void *set_exception_table_evt(unsigned int evt, void *handler)
+{
+ return set_exception_table_vec(evt >> 5, handler);
+}
+
+/* XXX
+ * disable hlt during certain critical i/o operations
+ */
+#define HAVE_DISABLE_HLT
+void disable_hlt(void);
+void enable_hlt(void);
+
+#define arch_align_stack(x) (x)
+
+#endif