ARM: 7660/1: tlb: add branch predictor maintenance operations
The ARM architecture requires explicit branch predictor maintenance
when updating an instruction stream for a given virtual address. In
reality, this isn't so much of a burden because the branch predictor
is flushed during the cache maintenance required to make the new
instructions visible to the I-side of the processor.
However, there are still some cases where explicit flushing is required,
so add a local_bp_flush_all operation to deal with this.
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/arch/arm/kernel/smp_tlb.c b/arch/arm/kernel/smp_tlb.c
index 02c5d2c..bd03005 100644
--- a/arch/arm/kernel/smp_tlb.c
+++ b/arch/arm/kernel/smp_tlb.c
@@ -64,6 +64,11 @@
local_flush_tlb_kernel_range(ta->ta_start, ta->ta_end);
}
+static inline void ipi_flush_bp_all(void *ignored)
+{
+ local_flush_bp_all();
+}
+
void flush_tlb_all(void)
{
if (tlb_ops_need_broadcast())
@@ -127,3 +132,10 @@
local_flush_tlb_kernel_range(start, end);
}
+void flush_bp_all(void)
+{
+ if (tlb_ops_need_broadcast())
+ on_each_cpu(ipi_flush_bp_all, NULL, 1);
+ else
+ local_flush_bp_all();
+}