Disintegrate asm/system.h for Sparc

Disintegrate asm/system.h for Sparc.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: sparclinux@vger.kernel.org

arch/sparc/include/asm/atomic_32.h

@@ -13,9 +13,9 @@
 
 #include <linux/types.h>
 
+#include <asm/cmpxchg.h>
 #include <asm-generic/atomic64.h>
 
-#include <asm/system.h>
 
 #define ATOMIC_INIT(i)  { (i) }
 

arch/sparc/include/asm/atomic_64.h

@@ -8,7 +8,7 @@
 #define __ARCH_SPARC64_ATOMIC__
 
 #include <linux/types.h>
-#include <asm/system.h>
+#include <asm/cmpxchg.h>
 
 #define ATOMIC_INIT(i)		{ (i) }
 #define ATOMIC64_INIT(i)	{ (i) }
@@ -85,7 +85,6 @@ static inline int __atomic_add_unless(atomic_t *v, int a, int u)
 	return c;
 }
 
-
 #define atomic64_cmpxchg(v, o, n) \
 	((__typeof__((v)->counter))cmpxchg(&((v)->counter), (o), (n)))
 #define atomic64_xchg(v, new) (xchg(&((v)->counter), new))

arch/sparc/include/asm/auxio_32.h

@@ -6,7 +6,6 @@
 #ifndef _SPARC_AUXIO_H
 #define _SPARC_AUXIO_H
 
-#include <asm/system.h>
 #include <asm/vaddrs.h>
 
 /* This register is an unsigned char in IO space.  It does two things.

arch/sparc/include/asm/barrier.h

@@ -0,0 +1,8 @@
+#ifndef ___ASM_SPARC_BARRIER_H
+#define ___ASM_SPARC_BARRIER_H
+#if defined(__sparc__) && defined(__arch64__)
+#include <asm/barrier_64.h>
+#else
+#include <asm/barrier_32.h>
+#endif
+#endif

arch/sparc/include/asm/barrier_32.h

@@ -0,0 +1,15 @@
+#ifndef __SPARC_BARRIER_H
+#define __SPARC_BARRIER_H
+
+/* XXX Change this if we ever use a PSO mode kernel. */
+#define mb()	__asm__ __volatile__ ("" : : : "memory")
+#define rmb()	mb()
+#define wmb()	mb()
+#define read_barrier_depends()	do { } while(0)
+#define set_mb(__var, __value)  do { __var = __value; mb(); } while(0)
+#define smp_mb()	__asm__ __volatile__("":::"memory")
+#define smp_rmb()	__asm__ __volatile__("":::"memory")
+#define smp_wmb()	__asm__ __volatile__("":::"memory")
+#define smp_read_barrier_depends()	do { } while(0)
+
+#endif /* !(__SPARC_BARRIER_H) */

arch/sparc/include/asm/barrier_64.h

@@ -0,0 +1,56 @@
+#ifndef __SPARC64_BARRIER_H
+#define __SPARC64_BARRIER_H
+
+/* These are here in an effort to more fully work around Spitfire Errata
+ * #51.  Essentially, if a memory barrier occurs soon after a mispredicted
+ * branch, the chip can stop executing instructions until a trap occurs.
+ * Therefore, if interrupts are disabled, the chip can hang forever.
+ *
+ * It used to be believed that the memory barrier had to be right in the
+ * delay slot, but a case has been traced recently wherein the memory barrier
+ * was one instruction after the branch delay slot and the chip still hung.
+ * The offending sequence was the following in sym_wakeup_done() of the
+ * sym53c8xx_2 driver:
+ *
+ *	call	sym_ccb_from_dsa, 0
+ *	 movge	%icc, 0, %l0
+ *	brz,pn	%o0, .LL1303
+ *	 mov	%o0, %l2
+ *	membar	#LoadLoad
+ *
+ * The branch has to be mispredicted for the bug to occur.  Therefore, we put
+ * the memory barrier explicitly into a "branch always, predicted taken"
+ * delay slot to avoid the problem case.
+ */
+#define membar_safe(type) \
+do {	__asm__ __volatile__("ba,pt	%%xcc, 1f\n\t" \
+			     " membar	" type "\n" \
+			     "1:\n" \
+			     : : : "memory"); \
+} while (0)
+
+/* The kernel always executes in TSO memory model these days,
+ * and furthermore most sparc64 chips implement more stringent
+ * memory ordering than required by the specifications.
+ */
+#define mb()	membar_safe("#StoreLoad")
+#define rmb()	__asm__ __volatile__("":::"memory")
+#define wmb()	__asm__ __volatile__("":::"memory")
+
+#define read_barrier_depends()		do { } while(0)
+#define set_mb(__var, __value) \
+	do { __var = __value; membar_safe("#StoreLoad"); } while(0)
+
+#ifdef CONFIG_SMP
+#define smp_mb()	mb()
+#define smp_rmb()	rmb()
+#define smp_wmb()	wmb()
+#else
+#define smp_mb()	__asm__ __volatile__("":::"memory")
+#define smp_rmb()	__asm__ __volatile__("":::"memory")
+#define smp_wmb()	__asm__ __volatile__("":::"memory")
+#endif
+
+#define smp_read_barrier_depends()	do { } while(0)
+
+#endif /* !(__SPARC64_BARRIER_H) */

arch/sparc/include/asm/bug.h

@@ -19,4 +19,7 @@ extern void do_BUG(const char *file, int line);
 
 #include <asm-generic/bug.h>
 
+struct pt_regs;
+extern void die_if_kernel(char *str, struct pt_regs *regs) __attribute__ ((noreturn));
+
 #endif

arch/sparc/include/asm/cacheflush_32.h

@@ -83,4 +83,13 @@ extern void sparc_flush_page_to_ram(struct page *page);
 #define flush_cache_vmap(start, end)		flush_cache_all()
 #define flush_cache_vunmap(start, end)		flush_cache_all()
 
+/* When a context switch happens we must flush all user windows so that
+ * the windows of the current process are flushed onto its stack. This
+ * way the windows are all clean for the next process and the stack
+ * frames are up to date.
+ */
+extern void flush_user_windows(void);
+extern void kill_user_windows(void);
+extern void flushw_all(void);
+
 #endif /* _SPARC_CACHEFLUSH_H */

arch/sparc/include/asm/cacheflush_64.h

@@ -9,6 +9,16 @@
 
 /* Cache flush operations. */
 
+
+#define flushi(addr)	__asm__ __volatile__ ("flush %0" : : "r" (addr) : "memory")
+#define flushw_all()	__asm__ __volatile__("flushw")
+
+extern void __flushw_user(void);
+#define flushw_user() __flushw_user()
+
+#define flush_user_windows flushw_user
+#define flush_register_windows flushw_all
+
 /* These are the same regardless of whether this is an SMP kernel or not. */
 #define flush_cache_mm(__mm) \
 	do { if ((__mm) == current->mm) flushw_user(); } while(0)

arch/sparc/include/asm/cmpxchg.h

@@ -0,0 +1,8 @@
+#ifndef ___ASM_SPARC_CMPXCHG_H
+#define ___ASM_SPARC_CMPXCHG_H
+#if defined(__sparc__) && defined(__arch64__)
+#include <asm/cmpxchg_64.h>
+#else
+#include <asm/cmpxchg_32.h>
+#endif
+#endif

arch/sparc/include/asm/cmpxchg_32.h

@@ -0,0 +1,112 @@
+/* 32-bit atomic xchg() and cmpxchg() definitions.
+ *
+ * Copyright (C) 1996 David S. Miller (davem@davemloft.net)
+ * Copyright (C) 2000 Anton Blanchard (anton@linuxcare.com.au)
+ * Copyright (C) 2007 Kyle McMartin (kyle@parisc-linux.org)
+ *
+ * Additions by Keith M Wesolowski (wesolows@foobazco.org) based
+ * on asm-parisc/atomic.h Copyright (C) 2000 Philipp Rumpf <prumpf@tux.org>.
+ */
+
+#ifndef __ARCH_SPARC_CMPXCHG__
+#define __ARCH_SPARC_CMPXCHG__
+
+#include <asm/btfixup.h>
+
+/* This has special calling conventions */
+#ifndef CONFIG_SMP
+BTFIXUPDEF_CALL(void, ___xchg32, void)
+#endif
+
+static inline unsigned long xchg_u32(__volatile__ unsigned long *m, unsigned long val)
+{
+#ifdef CONFIG_SMP
+	__asm__ __volatile__("swap [%2], %0"
+			     : "=&r" (val)
+			     : "0" (val), "r" (m)
+			     : "memory");
+	return val;
+#else
+	register unsigned long *ptr asm("g1");
+	register unsigned long ret asm("g2");
+
+	ptr = (unsigned long *) m;
+	ret = val;
+
+	/* Note: this is magic and the nop there is
+	   really needed. */
+	__asm__ __volatile__(
+	"mov	%%o7, %%g4\n\t"
+	"call	___f____xchg32\n\t"
+	" nop\n\t"
+	: "=&r" (ret)
+	: "0" (ret), "r" (ptr)
+	: "g3", "g4", "g7", "memory", "cc");
+
+	return ret;
+#endif
+}
+
+extern void __xchg_called_with_bad_pointer(void);
+
+static inline unsigned long __xchg(unsigned long x, __volatile__ void * ptr, int size)
+{
+	switch (size) {
+	case 4:
+		return xchg_u32(ptr, x);
+	}
+	__xchg_called_with_bad_pointer();
+	return x;
+}
+
+#define xchg(ptr,x) ((__typeof__(*(ptr)))__xchg((unsigned long)(x),(ptr),sizeof(*(ptr))))
+
+/* Emulate cmpxchg() the same way we emulate atomics,
+ * by hashing the object address and indexing into an array
+ * of spinlocks to get a bit of performance...
+ *
+ * See arch/sparc/lib/atomic32.c for implementation.
+ *
+ * Cribbed from <asm-parisc/atomic.h>
+ */
+#define __HAVE_ARCH_CMPXCHG	1
+
+/* bug catcher for when unsupported size is used - won't link */
+extern void __cmpxchg_called_with_bad_pointer(void);
+/* we only need to support cmpxchg of a u32 on sparc */
+extern unsigned long __cmpxchg_u32(volatile u32 *m, u32 old, u32 new_);
+
+/* don't worry...optimizer will get rid of most of this */
+static inline unsigned long
+__cmpxchg(volatile void *ptr, unsigned long old, unsigned long new_, int size)
+{
+	switch (size) {
+	case 4:
+		return __cmpxchg_u32((u32 *)ptr, (u32)old, (u32)new_);
+	default:
+		__cmpxchg_called_with_bad_pointer();
+		break;
+	}
+	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)));		\
+})
+
+#include <asm-generic/cmpxchg-local.h>
+
+/*
+ * cmpxchg_local and cmpxchg64_local are atomic wrt current CPU. Always make
+ * them available.
+ */
+#define cmpxchg_local(ptr, o, n)				  	       \
+	((__typeof__(*(ptr)))__cmpxchg_local_generic((ptr), (unsigned long)(o),\
+			(unsigned long)(n), sizeof(*(ptr))))
+#define cmpxchg64_local(ptr, o, n) __cmpxchg64_local_generic((ptr), (o), (n))
+
+#endif /* __ARCH_SPARC_CMPXCHG__ */