patch-2.4.0-test7 linux/include/asm-arm/proc-armo/locks.h

• Lines: 159
• Date: Sun Aug 13 09:54:15 2000
• Orig file: v2.4.0-test6/linux/include/asm-arm/proc-armo/locks.h
• Orig date: Wed Dec 31 16:00:00 1969

diff -u --recursive --new-file v2.4.0-test6/linux/include/asm-arm/proc-armo/locks.h linux/include/asm-arm/proc-armo/locks.h
@@ -0,0 +1,158 @@
+/*
+ * linux/include/asm-arm/proc-armo/locks.h
+ *
+ * Copyright (C) 2000 Russell King
+ * Fixes for 26 bit machines, (C) 2000 Dave Gilbert
+ *
+ * Interrupt safe locking assembler. 
+ *
+ */
+#ifndef __ASM_PROC_LOCKS_H
+#define __ASM_PROC_LOCKS_H
+
+/* Decrements by 1, fails if value < 0 */
+#define __down_op(ptr,fail)			\
+	({					\
+	__asm__ __volatile__ (			\
+	"@ atomic down operation\n"		\
+"	mov	r0, pc\n"			\
+"	orr	lr, r0, #0x08000000\n"		\
+"	teqp	lr, #0\n"			\
+"	ldr	lr, [%0]\n"			\
+"	and	r0, r0, #0x0c000003\n"		\
+"	subs	lr, lr, #1\n"			\
+"	str	lr, [%0]\n"			\
+"	orrmi	r0, r0, #0x80000000	@ set N\n" \
+"	teqp	r0, #0\n"			\
+"	movmi	r0, %0\n"			\
+"	blmi	" SYMBOL_NAME_STR(fail)		\
+	:					\
+	: "r" (ptr)				\
+	: "r0", "lr", "cc");			\
+	})
+
+#define __down_op_ret(ptr,fail)			\
+	({					\
+		unsigned int result;		\
+	__asm__ __volatile__ (			\
+"	@ down_op_ret\n"			\
+"	mov	r0, pc\n"			\
+"	orr	lr, r0, #0x08000000\n"		\
+"	teqp	lr, #0\n"			\
+"	ldr	lr, [%1]\n"			\
+"	and	r0, r0, #0x0c000003\n"		\
+"	subs	lr, lr, #1\n"			\
+"	str	lr, [%1]\n"			\
+"	orrmi	r0, r0, #0x80000000	@ set N\n" \
+"	teqp	r0, #0\n"			\
+"	movmi	r0, %1\n"			\
+"	movpl	r0, #0\n"			\
+"	blmi	" SYMBOL_NAME_STR(fail) "\n"	\
+"	mov	%0, r0"				\
+	: "=&r" (result)			\
+	: "r" (ptr)				\
+	: "r0", "lr", "cc");			\
+	result;					\
+	})
+
+#define __up_op(ptr,wake)			\
+	({					\
+	__asm__ __volatile__ (			\
+	"@ up_op\n"				\
+"	mov	r0, pc\n"			\
+"	orr	lr, r0, #0x08000000\n"		\
+"	teqp	lr, #0\n"			\
+"	ldr	lr, [%0]\n"			\
+"	and	r0, r0, #0x0c000003\n"		\
+"	adds	lr, lr, #1\n"			\
+"	str	lr, [%0]\n"			\
+"	orrle	r0, r0, #0x80000000	@ set N - should this be mi ??? DAG ! \n" \
+"	teqp	r0, #0\n"			\
+"	movmi	r0, %0\n"			\
+"	blmi	" SYMBOL_NAME_STR(wake)		\
+	:					\
+	: "r" (ptr)				\
+	: "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 RW_LOCK_BIAS_STR "0x01000000"
+
+/* Decrements by RW_LOCK_BIAS rather than 1, fails if value != 0 */
+#define __down_op_write(ptr,fail)		\
+	({					\
+	__asm__ __volatile__(			\
+	"@ down_op_write\n"			\
+"	mov	r0, pc\n"			\
+"	orr	lr, r0, #0x08000000\n"		\
+"	teqp	lr, #0\n"			\
+"	and	r0, r0, #0x0c000003\n"		\
+\
+"	ldr	lr, [%0]\n"			\
+"	subs	lr, lr, %1\n"			\
+"	str	lr, [%0]\n"			\
+\
+" orreq r0, r0, #0x40000000 @ set Z \n"\
+"	teqp	r0, #0\n"			\
+"	movne	r0, %0\n"			\
+"	blne	" SYMBOL_NAME_STR(fail)		\
+	:					\
+	: "r" (ptr), "I" (RW_LOCK_BIAS)		\
+	: "r0", "lr", "cc");			\
+	})
+
+/* Increments by RW_LOCK_BIAS, wakes if value >= 0 */
+#define __up_op_write(ptr,wake)			\
+	({					\
+	__asm__ __volatile__(			\
+	"@ up_op_read\n"			\
+"	mov	r0, pc\n"			\
+"	orr	lr, r0, #0x08000000\n"		\
+"	teqp	lr, #0\n"			\
+\
+"	ldr	lr, [%0]\n"			\
+"	and	r0, r0, #0x0c000003\n"		\
+"	adds	lr, lr, %1\n"			\
+"	str	lr, [%0]\n"			\
+\
+" orrcs r0, r0, #0x20000000 @ set C\n" \
+"	teqp	r0, #0\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"			\
+"	mov	r0, pc\n"			\
+"	orr	lr, r0, #0x08000000\n"		\
+"	teqp	lr, #0\n"			\
+\
+"	ldr	lr, [%0]\n"			\
+"	and	r0, r0, #0x0c000003\n"		\
+"	adds	lr, lr, %1\n"			\
+"	str	lr, [%0]\n"			\
+\
+" orreq r0, r0, #0x40000000 @ Set Z \n" \
+"	teqp	r0, #0\n"			\
+"	moveq	r0, %0\n"			\
+"	bleq	" SYMBOL_NAME_STR(wake)		\
+	:					\
+	: "r" (ptr), "I" (1)			\
+	: "r0", "lr", "cc");			\
+	})
+
+#endif