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authorYang Zhang <yang.z.zhang@intel.com>2015-08-28 09:58:54 +0800
committerYang Zhang <yang.z.zhang@intel.com>2015-09-01 12:44:00 +0800
commite44e3482bdb4d0ebde2d8b41830ac2cdb07948fb (patch)
tree66b09f592c55df2878107a468a91d21506104d3f /qemu/roms/openbios/arch/ppc/timebase.S
parent9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (diff)
Add qemu 2.4.0
Change-Id: Ic99cbad4b61f8b127b7dc74d04576c0bcbaaf4f5 Signed-off-by: Yang Zhang <yang.z.zhang@intel.com>
Diffstat (limited to 'qemu/roms/openbios/arch/ppc/timebase.S')
-rw-r--r--qemu/roms/openbios/arch/ppc/timebase.S33
1 files changed, 33 insertions, 0 deletions
diff --git a/qemu/roms/openbios/arch/ppc/timebase.S b/qemu/roms/openbios/arch/ppc/timebase.S
new file mode 100644
index 000000000..19faed49d
--- /dev/null
+++ b/qemu/roms/openbios/arch/ppc/timebase.S
@@ -0,0 +1,33 @@
+#include "asm/asmdefs.h"
+#include "asm/processor.h"
+
+/*
+ * unsigned long long _get_ticks(void);
+ */
+_GLOBAL(_get_ticks):
+1: mftbu r3
+ mftb r4
+ mftbu r5
+ cmpw 0,r3,r5
+ bne 1b
+ blr
+
+/*
+ * Delay for a number of ticks
+ */
+_GLOBAL(_wait_ticks):
+ mflr r8 /* save link register */
+ mr r7, r3 /* save tick count */
+ bl BRANCH_LABEL(_get_ticks) /* Get start time */
+
+ /* Calculate end time */
+ addc r7, r4, r7 /* Compute end time lower */
+ addze r6, r3 /* and end time upper */
+
+1: bl BRANCH_LABEL(_get_ticks) /* Get current time */
+ subfc r4, r4, r7 /* Subtract current time from end time */
+ subfe. r3, r3, r6
+ bge 1b /* Loop until time expired */
+
+ mtlr r8 /* restore link register */
+ blr