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authorLinus Torvalds <torvalds@linux-foundation.org>2008-08-01 10:53:43 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2008-08-01 10:53:43 -0700
commit00e9028a95fb8a4d79f2fb695a853f33ea7d3b57 (patch)
tree2dea2ae498a6ce57de8890e87185aca5e9f3ad2d /arch/sh/include/asm/spinlock.h
parent57b1494d2ba544c62673234da6115c21fac27ffc (diff)
parent7cb93181629c613ee2b8f4ffe3446f8003074842 (diff)
Merge git://git.kernel.org/pub/scm/linux/kernel/git/lethal/sh-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/lethal/sh-2.6: (28 commits) mm/hugetlb.c must #include <asm/io.h> video: Fix up hp6xx driver build regressions. sh: defconfig updates. sh: Kill off stray mach-rsk7203 reference. serial: sh-sci: Fix up SH7760/SH7780/SH7785 early printk regression. sh: Move out individual boards without mach groups. sh: Make sure AT_SYSINFO_EHDR is exposed to userspace in asm/auxvec.h. sh: Allow SH-3 and SH-5 to use common headers. sh: Provide common CPU headers, prune the SH-2 and SH-2A directories. sh/maple: clean maple bus code sh: More header path fixups for mach dir refactoring. sh: Move out the solution engine headers to arch/sh/include/mach-se/ sh: I2C fix for AP325RXA and Migo-R sh: Shuffle the board directories in to mach groups. sh: dma-sh: Fix up dreamcast dma.h mach path. sh: Switch KBUILD_DEFCONFIG to shx3_defconfig. sh: Add ARCH_DEFCONFIG entries for sh and sh64. sh: Fix compile error of Solution Engine sh: Proper __put_user_asm() size mismatch fix. sh: Stub in a dummy ENTRY_OFFSET for uImage offset calculation. ...
Diffstat (limited to 'arch/sh/include/asm/spinlock.h')
-rw-r--r--arch/sh/include/asm/spinlock.h223
1 files changed, 223 insertions, 0 deletions
diff --git a/arch/sh/include/asm/spinlock.h b/arch/sh/include/asm/spinlock.h
new file mode 100644
index 00000000000..e793181d64d
--- /dev/null
+++ b/arch/sh/include/asm/spinlock.h
@@ -0,0 +1,223 @@
+/*
+ * include/asm-sh/spinlock.h
+ *
+ * Copyright (C) 2002, 2003 Paul Mundt
+ * Copyright (C) 2006, 2007 Akio Idehara
+ *
+ * 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.
+ */
+#ifndef __ASM_SH_SPINLOCK_H
+#define __ASM_SH_SPINLOCK_H
+
+/*
+ * The only locking implemented here uses SH-4A opcodes. For others,
+ * split this out as per atomic-*.h.
+ */
+#ifndef CONFIG_CPU_SH4A
+#error "Need movli.l/movco.l for spinlocks"
+#endif
+
+/*
+ * Your basic SMP spinlocks, allowing only a single CPU anywhere
+ */
+
+#define __raw_spin_is_locked(x) ((x)->lock <= 0)
+#define __raw_spin_lock_flags(lock, flags) __raw_spin_lock(lock)
+#define __raw_spin_unlock_wait(x) \
+ do { cpu_relax(); } while ((x)->lock)
+
+/*
+ * Simple spin lock operations. There are two variants, one clears IRQ's
+ * on the local processor, one does not.
+ *
+ * We make no fairness assumptions. They have a cost.
+ */
+static inline void __raw_spin_lock(raw_spinlock_t *lock)
+{
+ unsigned long tmp;
+ unsigned long oldval;
+
+ __asm__ __volatile__ (
+ "1: \n\t"
+ "movli.l @%2, %0 ! __raw_spin_lock \n\t"
+ "mov %0, %1 \n\t"
+ "mov #0, %0 \n\t"
+ "movco.l %0, @%2 \n\t"
+ "bf 1b \n\t"
+ "cmp/pl %1 \n\t"
+ "bf 1b \n\t"
+ : "=&z" (tmp), "=&r" (oldval)
+ : "r" (&lock->lock)
+ : "t", "memory"
+ );
+}
+
+static inline void __raw_spin_unlock(raw_spinlock_t *lock)
+{
+ unsigned long tmp;
+
+ __asm__ __volatile__ (
+ "mov #1, %0 ! __raw_spin_unlock \n\t"
+ "mov.l %0, @%1 \n\t"
+ : "=&z" (tmp)
+ : "r" (&lock->lock)
+ : "t", "memory"
+ );
+}
+
+static inline int __raw_spin_trylock(raw_spinlock_t *lock)
+{
+ unsigned long tmp, oldval;
+
+ __asm__ __volatile__ (
+ "1: \n\t"
+ "movli.l @%2, %0 ! __raw_spin_trylock \n\t"
+ "mov %0, %1 \n\t"
+ "mov #0, %0 \n\t"
+ "movco.l %0, @%2 \n\t"
+ "bf 1b \n\t"
+ "synco \n\t"
+ : "=&z" (tmp), "=&r" (oldval)
+ : "r" (&lock->lock)
+ : "t", "memory"
+ );
+
+ return oldval;
+}
+
+/*
+ * Read-write spinlocks, allowing multiple readers but only one writer.
+ *
+ * NOTE! it is quite common to have readers in interrupts but no interrupt
+ * writers. For those circumstances we can "mix" irq-safe locks - any writer
+ * needs to get a irq-safe write-lock, but readers can get non-irqsafe
+ * read-locks.
+ */
+
+/**
+ * read_can_lock - would read_trylock() succeed?
+ * @lock: the rwlock in question.
+ */
+#define __raw_read_can_lock(x) ((x)->lock > 0)
+
+/**
+ * write_can_lock - would write_trylock() succeed?
+ * @lock: the rwlock in question.
+ */
+#define __raw_write_can_lock(x) ((x)->lock == RW_LOCK_BIAS)
+
+static inline void __raw_read_lock(raw_rwlock_t *rw)
+{
+ unsigned long tmp;
+
+ __asm__ __volatile__ (
+ "1: \n\t"
+ "movli.l @%1, %0 ! __raw_read_lock \n\t"
+ "cmp/pl %0 \n\t"
+ "bf 1b \n\t"
+ "add #-1, %0 \n\t"
+ "movco.l %0, @%1 \n\t"
+ "bf 1b \n\t"
+ : "=&z" (tmp)
+ : "r" (&rw->lock)
+ : "t", "memory"
+ );
+}
+
+static inline void __raw_read_unlock(raw_rwlock_t *rw)
+{
+ unsigned long tmp;
+
+ __asm__ __volatile__ (
+ "1: \n\t"
+ "movli.l @%1, %0 ! __raw_read_unlock \n\t"
+ "add #1, %0 \n\t"
+ "movco.l %0, @%1 \n\t"
+ "bf 1b \n\t"
+ : "=&z" (tmp)
+ : "r" (&rw->lock)
+ : "t", "memory"
+ );
+}
+
+static inline void __raw_write_lock(raw_rwlock_t *rw)
+{
+ unsigned long tmp;
+
+ __asm__ __volatile__ (
+ "1: \n\t"
+ "movli.l @%1, %0 ! __raw_write_lock \n\t"
+ "cmp/hs %2, %0 \n\t"
+ "bf 1b \n\t"
+ "sub %2, %0 \n\t"
+ "movco.l %0, @%1 \n\t"
+ "bf 1b \n\t"
+ : "=&z" (tmp)
+ : "r" (&rw->lock), "r" (RW_LOCK_BIAS)
+ : "t", "memory"
+ );
+}
+
+static inline void __raw_write_unlock(raw_rwlock_t *rw)
+{
+ __asm__ __volatile__ (
+ "mov.l %1, @%0 ! __raw_write_unlock \n\t"
+ :
+ : "r" (&rw->lock), "r" (RW_LOCK_BIAS)
+ : "t", "memory"
+ );
+}
+
+static inline int __raw_read_trylock(raw_rwlock_t *rw)
+{
+ unsigned long tmp, oldval;
+
+ __asm__ __volatile__ (
+ "1: \n\t"
+ "movli.l @%2, %0 ! __raw_read_trylock \n\t"
+ "mov %0, %1 \n\t"
+ "cmp/pl %0 \n\t"
+ "bf 2f \n\t"
+ "add #-1, %0 \n\t"
+ "movco.l %0, @%2 \n\t"
+ "bf 1b \n\t"
+ "2: \n\t"
+ "synco \n\t"
+ : "=&z" (tmp), "=&r" (oldval)
+ : "r" (&rw->lock)
+ : "t", "memory"
+ );
+
+ return (oldval > 0);
+}
+
+static inline int __raw_write_trylock(raw_rwlock_t *rw)
+{
+ unsigned long tmp, oldval;
+
+ __asm__ __volatile__ (
+ "1: \n\t"
+ "movli.l @%2, %0 ! __raw_write_trylock \n\t"
+ "mov %0, %1 \n\t"
+ "cmp/hs %3, %0 \n\t"
+ "bf 2f \n\t"
+ "sub %3, %0 \n\t"
+ "2: \n\t"
+ "movco.l %0, @%2 \n\t"
+ "bf 1b \n\t"
+ "synco \n\t"
+ : "=&z" (tmp), "=&r" (oldval)
+ : "r" (&rw->lock), "r" (RW_LOCK_BIAS)
+ : "t", "memory"
+ );
+
+ return (oldval > (RW_LOCK_BIAS - 1));
+}
+
+#define _raw_spin_relax(lock) cpu_relax()
+#define _raw_read_relax(lock) cpu_relax()
+#define _raw_write_relax(lock) cpu_relax()
+
+#endif /* __ASM_SH_SPINLOCK_H */