patch-2.3.45 linux/include/asm-arm/proc-armv/locks.h

• Lines: 135
• Date: Sun Feb 13 10:47:01 2000
• Orig file: v2.3.44/linux/include/asm-arm/proc-armv/locks.h
• Orig date: Wed Dec 31 16:00:00 1969

diff -u --recursive --new-file v2.3.44/linux/include/asm-arm/proc-armv/locks.h linux/include/asm-arm/proc-armv/locks.h
@@ -0,0 +1,134 @@
+/*
+ * linux/include/asm-arm/proc-armv/locks.h
+ *
+ * Copyright (C) 2000 Russell King
+ *
+ * Interrupt safe locking assembler. 
+ */
+#ifndef __ASM_PROC_LOCKS_H
+#define __ASM_PROC_LOCKS_H
+
+#define __down_op(ptr,fail)			\
+	({					\
+	__asm__ __volatile__(			\
+	"@ down_op\n"				\
+"	mrs	r0, cpsr\n"			\
+"	orr	lr, r0, #128\n"			\
+"	msr	cpsr_c, lr\n"			\
+"	ldr	lr, [%0]\n"			\
+"	subs	lr, lr, %1\n"			\
+"	str	lr, [%0]\n"			\
+"	msr	cpsr_c, r0\n"			\
+"	movmi	r0, %0\n"			\
+"	blmi	" SYMBOL_NAME_STR(fail)		\
+	:					\
+	: "r" (ptr), "I" (1)			\
+	: "r0", "lr", "cc");			\
+	})
+
+#define __down_op_ret(ptr,fail)			\
+	({					\
+		unsigned int ret;		\
+	__asm__ __volatile__(			\
+	"@ down_op_ret\n"			\
+"	mrs	r0, cpsr\n"			\
+"	orr	lr, r0, #128\n"			\
+"	msr	cpsr_c, lr\n"			\
+"	ldr	lr, [%1]\n"			\
+"	subs	lr, lr, %2\n"			\
+"	str	lr, [%1]\n"			\
+"	msr	cpsr_c, r0\n"			\
+"	movmi	r0, %1\n"			\
+"	movpl	r0, #0\n"			\
+"	blmi	" SYMBOL_NAME_STR(fail) "\n"	\
+"	mov	%0, r0"				\
+	: "=&r" (ret)				\
+	: "r" (ptr), "I" (1)			\
+	: "r0", "lr", "cc");			\
+	ret;					\
+	})
+
+#define __up_op(ptr,wake)			\
+	({					\
+	__asm__ __volatile__(			\
+	"@ up_op\n"				\
+"	mrs	r0, cpsr\n"			\
+"	orr	lr, r0, #128\n"			\
+"	msr	cpsr_c, lr\n"			\
+"	ldr	lr, [%0]\n"			\
+"	adds	lr, lr, %1\n"			\
+"	str	lr, [%0]\n"			\
+"	msr	cpsr_c, r0\n"			\
+"	movle	r0, %0\n"			\
+"	blle	" SYMBOL_NAME_STR(wake)		\
+	:					\
+	: "r" (ptr), "I" (1)			\
+	: "r0", "lr", "cc");			\
+	})
+
+/*
+ * The value 0x01000000 supports up to 128 processors and
+ * lots of processes.  BIAS must be chosen such that sub'ing
+ * BIAS once per CPU will result in the long remaining
+ * negative.
+ */
+#define RW_LOCK_BIAS	0x01000000
+
+#define __down_op_write(ptr,fail)		\
+	({					\
+	__asm__ __volatile__(			\
+	"@ down_op_write\n"			\
+"	mrs	r0, cpsr\n"			\
+"	orr	lr, r0, #128\n"			\
+"	msr	cpsr_c, lr\n"			\
+"	ldr	lr, [%0]\n"			\
+"	subs	lr, lr, %1\n"			\
+"	str	lr, [%0]\n"			\
+"	msr	cpsr_c, r0\n"			\
+"	movne	r0, %0\n"			\
+"	blne	" SYMBOL_NAME_STR(fail)		\
+	:					\
+	: "r" (ptr), "I" (RW_LOCK_BIAS)		\
+	: "r0", "lr", "cc");			\
+	})
+
+#define __up_op_write(ptr,wake)			\
+	({					\
+	__asm__ __volatile__(			\
+	"@ up_op_read\n"			\
+"	mrs	r0, cpsr\n"			\
+"	orr	lr, r0, #128\n"			\
+"	msr	cpsr_c, lr\n"			\
+"	ldr	lr, [%0]\n"			\
+"	adds	lr, lr, %1\n"			\
+"	str	lr, [%0]\n"			\
+"	msr	cpsr_c, r0\n"			\
+"	movcs	r0, %0\n"			\
+"	blcs	" SYMBOL_NAME_STR(wake)		\
+	:					\
+	: "r" (ptr), "I" (RW_LOCK_BIAS)		\
+	: "r0", "lr", "cc");			\
+	})
+
+#define __down_op_read(ptr,fail)		\
+	__down_op(ptr, fail)
+
+#define __up_op_read(ptr,wake)			\
+	({					\
+	__asm__ __volatile__(			\
+	"@ up_op_read\n"			\
+"	mrs	r0, cpsr\n"			\
+"	orr	lr, r0, #128\n"			\
+"	msr	cpsr_c, lr\n"			\
+"	ldr	lr, [%0]\n"			\
+"	adds	lr, lr, %1\n"			\
+"	str	lr, [%0]\n"			\
+"	msr	cpsr_c, r0\n"			\
+"	moveq	r0, %0\n"			\
+"	bleq	" SYMBOL_NAME_STR(wake)		\
+	:					\
+	: "r" (ptr), "I" (1)			\
+	: "r0", "lr", "cc");			\
+	})
+
+#endif