MIPS: Put PGD in C0_CONTEXT for 64-bit R2 processors.
Processors that support the mips64r2 ISA can in four instructions
convert a shifted PGD pointer stored in the upper bits of c0_context
into a usable pointer. By doing this we save a memory load and
associated potential cache miss in the TLB exception handlers.
Since the upper bits of c0_context were holding the CPU number, we
move this to the upper bits of c0_xcontext which doesn't have enough
bits to hold the PGD pointer, but has plenty for the CPU number.
Signed-off-by: David Daney <ddaney@caviumnetworks.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig
index f6f3b99..20b223b 100644
--- a/arch/mips/Kconfig
+++ b/arch/mips/Kconfig
@@ -1427,6 +1427,9 @@
bool
config CPU_SUPPORTS_HUGEPAGES
bool
+config MIPS_PGD_C0_CONTEXT
+ bool
+ default y if 64BIT && CPU_MIPSR2
#
# Set to y for ptrace access to watch registers.