Blackfin/ipipe: prepare status bitops for SMP support
Signed-off-by: Philippe Gerum <rpm@xenomai.org>
Signed-off-by: Li Yi <yi.li@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
diff --git a/arch/blackfin/kernel/ipipe.c b/arch/blackfin/kernel/ipipe.c
index 5d73823..a77307a 100644
--- a/arch/blackfin/kernel/ipipe.c
+++ b/arch/blackfin/kernel/ipipe.c
@@ -335,3 +335,70 @@
__clear_bit(IPIPE_STALL_FLAG, &ipipe_root_cpudom_var(status));
bfin_sti(bfin_irq_flags);
}
+
+/*
+ * We could use standard atomic bitops in the following root status
+ * manipulation routines, but let's prepare for SMP support in the
+ * same move, preventing CPU migration as required.
+ */
+void __ipipe_stall_root(void)
+{
+ unsigned long *p, flags;
+
+ local_irq_save_hw(flags);
+ p = &__ipipe_root_status;
+ __set_bit(IPIPE_STALL_FLAG, p);
+ local_irq_restore_hw(flags);
+}
+EXPORT_SYMBOL(__ipipe_stall_root);
+
+unsigned long __ipipe_test_and_stall_root(void)
+{
+ unsigned long *p, flags;
+ int x;
+
+ local_irq_save_hw(flags);
+ p = &__ipipe_root_status;
+ x = __test_and_set_bit(IPIPE_STALL_FLAG, p);
+ local_irq_restore_hw(flags);
+
+ return x;
+}
+EXPORT_SYMBOL(__ipipe_test_and_stall_root);
+
+unsigned long __ipipe_test_root(void)
+{
+ const unsigned long *p;
+ unsigned long flags;
+ int x;
+
+ local_irq_save_hw_smp(flags);
+ p = &__ipipe_root_status;
+ x = test_bit(IPIPE_STALL_FLAG, p);
+ local_irq_restore_hw_smp(flags);
+
+ return x;
+}
+EXPORT_SYMBOL(__ipipe_test_root);
+
+void __ipipe_lock_root(void)
+{
+ unsigned long *p, flags;
+
+ local_irq_save_hw(flags);
+ p = &__ipipe_root_status;
+ __set_bit(IPIPE_SYNCDEFER_FLAG, p);
+ local_irq_restore_hw(flags);
+}
+EXPORT_SYMBOL(__ipipe_lock_root);
+
+void __ipipe_unlock_root(void)
+{
+ unsigned long *p, flags;
+
+ local_irq_save_hw(flags);
+ p = &__ipipe_root_status;
+ __clear_bit(IPIPE_SYNCDEFER_FLAG, p);
+ local_irq_restore_hw(flags);
+}
+EXPORT_SYMBOL(__ipipe_unlock_root);