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authorthl <thl@3c298f89-4303-0410-b956-a3cf2f4a3e73>2008-12-16 14:07:55 +0000
committerthl <thl@3c298f89-4303-0410-b956-a3cf2f4a3e73>2008-12-16 14:07:55 +0000
commit6ad1668c37fef80075e1a69b0ef71d0f8bbeb9c3 (patch)
tree07dc39510a01c7dca62cd1d2a794c1800ecab6c2 /target/linux/ifxmips/patches-2.6.27/010-mips_clocksource_init_war.patch
parent84938fc03d0471ec555fecec3569f25cd1ace3ed (diff)
[ifxmips] cleanup sources and prepare for 2.6.27
git-svn-id: svn://svn.openwrt.org/openwrt/trunk@13660 3c298f89-4303-0410-b956-a3cf2f4a3e73
Diffstat (limited to 'target/linux/ifxmips/patches-2.6.27/010-mips_clocksource_init_war.patch')
-rw-r--r--target/linux/ifxmips/patches-2.6.27/010-mips_clocksource_init_war.patch33
1 files changed, 33 insertions, 0 deletions
diff --git a/target/linux/ifxmips/patches-2.6.27/010-mips_clocksource_init_war.patch b/target/linux/ifxmips/patches-2.6.27/010-mips_clocksource_init_war.patch
new file mode 100644
index 0000000000..ac44c308fa
--- /dev/null
+++ b/target/linux/ifxmips/patches-2.6.27/010-mips_clocksource_init_war.patch
@@ -0,0 +1,33 @@
+--- a/arch/mips/kernel/cevt-r4k.c
++++ b/arch/mips/kernel/cevt-r4k.c
+@@ -21,6 +21,22 @@
+
+ #ifndef CONFIG_MIPS_MT_SMTC
+
++/*
++ * Compare interrupt can be routed and latched outside the core,
++ * so a single execution hazard barrier may not be enough to give
++ * it time to clear as seen in the Cause register. 4 time the
++ * pipeline depth seems reasonably conservative, and empirically
++ * works better in configurations with high CPU/bus clock ratios.
++ */
++
++#define compare_change_hazard() \
++ do { \
++ irq_disable_hazard(); \
++ irq_disable_hazard(); \
++ irq_disable_hazard(); \
++ irq_disable_hazard(); \
++ } while (0)
++
+ static int mips_next_event(unsigned long delta,
+ struct clock_event_device *evt)
+ {
+@@ -30,6 +46,7 @@ static int mips_next_event(unsigned long
+ cnt = read_c0_count();
+ cnt += delta;
+ write_c0_compare(cnt);
++ compare_change_hazard();
+ res = ((int)(read_c0_count() - cnt) > 0) ? -ETIME : 0;
+ return res;
+ }