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
diff --git a/arch/sparc/include/asm/switch_to_64.h b/arch/sparc/include/asm/switch_to_64.h
new file mode 100644
index 0000000..7923c4a
--- /dev/null
+++ b/arch/sparc/include/asm/switch_to_64.h
@@ -0,0 +1,72 @@
+#ifndef __SPARC64_SWITCH_TO_64_H
+#define __SPARC64_SWITCH_TO_64_H
+
+#include <asm/visasm.h>
+
+#define prepare_arch_switch(next) \
+do { \
+ flushw_all(); \
+} while (0)
+
+ /* See what happens when you design the chip correctly?
+ *
+ * We tell gcc we clobber all non-fixed-usage registers except
+ * for l0/l1. It will use one for 'next' and the other to hold
+ * the output value of 'last'. 'next' is not referenced again
+ * past the invocation of switch_to in the scheduler, so we need
+ * not preserve it's value. Hairy, but it lets us remove 2 loads
+ * and 2 stores in this critical code path. -DaveM
+ */
+#define switch_to(prev, next, last) \
+do { flush_tlb_pending(); \
+ save_and_clear_fpu(); \
+ /* If you are tempted to conditionalize the following */ \
+ /* so that ASI is only written if it changes, think again. */ \
+ __asm__ __volatile__("wr %%g0, %0, %%asi" \
+ : : "r" (__thread_flag_byte_ptr(task_thread_info(next))[TI_FLAG_BYTE_CURRENT_DS]));\
+ trap_block[current_thread_info()->cpu].thread = \
+ task_thread_info(next); \
+ __asm__ __volatile__( \
+ "mov %%g4, %%g7\n\t" \
+ "stx %%i6, [%%sp + 2047 + 0x70]\n\t" \
+ "stx %%i7, [%%sp + 2047 + 0x78]\n\t" \
+ "rdpr %%wstate, %%o5\n\t" \
+ "stx %%o6, [%%g6 + %6]\n\t" \
+ "stb %%o5, [%%g6 + %5]\n\t" \
+ "rdpr %%cwp, %%o5\n\t" \
+ "stb %%o5, [%%g6 + %8]\n\t" \
+ "wrpr %%g0, 15, %%pil\n\t" \
+ "mov %4, %%g6\n\t" \
+ "ldub [%4 + %8], %%g1\n\t" \
+ "wrpr %%g1, %%cwp\n\t" \
+ "ldx [%%g6 + %6], %%o6\n\t" \
+ "ldub [%%g6 + %5], %%o5\n\t" \
+ "ldub [%%g6 + %7], %%o7\n\t" \
+ "wrpr %%o5, 0x0, %%wstate\n\t" \
+ "ldx [%%sp + 2047 + 0x70], %%i6\n\t" \
+ "ldx [%%sp + 2047 + 0x78], %%i7\n\t" \
+ "ldx [%%g6 + %9], %%g4\n\t" \
+ "wrpr %%g0, 14, %%pil\n\t" \
+ "brz,pt %%o7, switch_to_pc\n\t" \
+ " mov %%g7, %0\n\t" \
+ "sethi %%hi(ret_from_syscall), %%g1\n\t" \
+ "jmpl %%g1 + %%lo(ret_from_syscall), %%g0\n\t" \
+ " nop\n\t" \
+ ".globl switch_to_pc\n\t" \
+ "switch_to_pc:\n\t" \
+ : "=&r" (last), "=r" (current), "=r" (current_thread_info_reg), \
+ "=r" (__local_per_cpu_offset) \
+ : "0" (task_thread_info(next)), \
+ "i" (TI_WSTATE), "i" (TI_KSP), "i" (TI_NEW_CHILD), \
+ "i" (TI_CWP), "i" (TI_TASK) \
+ : "cc", \
+ "g1", "g2", "g3", "g7", \
+ "l1", "l2", "l3", "l4", "l5", "l6", "l7", \
+ "i0", "i1", "i2", "i3", "i4", "i5", \
+ "o0", "o1", "o2", "o3", "o4", "o5", "o7"); \
+} while(0)
+
+extern void synchronize_user_stack(void);
+extern void fault_in_user_windows(void);
+
+#endif /* __SPARC64_SWITCH_TO_64_H */