Power ISA v3.1 implementations in the Linux Compliancy Subset and
lower are not required to implement broadcast TLBIE, and in fact
Microwatt doesn't. To avoid the need to specify "disable_tlbie" on
the kernel command line on SMP Microwatt systems, this defines a
config option that asserts that broadcast TLBIE should never be used
(the kernel will instead use IPIs to trigger local TLBIEs on other
CPUs when required).
Signed-off-by: Paul Mackerras <pau...@ozlabs.org>
---
arch/powerpc/mm/book3s64/pgtable.c | 10 ++++++++--
arch/powerpc/platforms/Kconfig.cputype | 12 ++++++++++++
arch/powerpc/platforms/microwatt/Kconfig | 1 +
3 files changed, 21 insertions(+), 2 deletions(-)
diff --git a/arch/powerpc/mm/book3s64/pgtable.c
b/arch/powerpc/mm/book3s64/pgtable.c
index 374542528080..14ee96e2a581 100644
--- a/arch/powerpc/mm/book3s64/pgtable.c
+++ b/arch/powerpc/mm/book3s64/pgtable.c
@@ -588,10 +588,16 @@ int pmd_move_must_withdraw(struct spinlock *new_pmd_ptl,
}
#endif
+#ifndef CONFIG_PPC_RADIX_NO_BROADCAST_TLBIE
+#define DEFAULT_TLBIE_ENABLE true
+#else
+#define DEFAULT_TLBIE_ENABLE false
+#endif
+
/*
* Does the CPU support tlbie?
*/
-bool tlbie_capable __read_mostly = true;
+bool tlbie_capable __read_mostly = DEFAULT_TLBIE_ENABLE;
EXPORT_SYMBOL(tlbie_capable);
/*
@@ -599,7 +605,7 @@ EXPORT_SYMBOL(tlbie_capable);
* address spaces? tlbie may still be used for nMMU accelerators, and for KVM
* guest address spaces.
*/
-bool tlbie_enabled __read_mostly = true;
+bool tlbie_enabled __read_mostly = DEFAULT_TLBIE_ENABLE;
static int __init setup_disable_tlbie(char *str)
{
diff --git a/arch/powerpc/platforms/Kconfig.cputype
b/arch/powerpc/platforms/Kconfig.cputype
index 1453ccc900c4..bd2a4e46ab34 100644
--- a/arch/powerpc/platforms/Kconfig.cputype
+++ b/arch/powerpc/platforms/Kconfig.cputype
@@ -449,6 +449,18 @@ config PPC_RADIX_MMU_DEFAULT
If you're unsure, say Y.
+config PPC_RADIX_NO_BROADCAST_TLBIE
+ depends on PPC_RADIX_MMU
+ help
+ Power ISA v3.1 implementations in the Linux Compliancy Subset
+ and lower are not required to implement broadcast TLBIE
+ instructions, that is, a TLB invalidation instruction
+ performed on one CPU is not required to operate on the TLBs
+ in all CPUs in the system. Instead, the kernel does an IPI
+ to each relevant CPU to get it to do a local TLBIE instruction.
+ Select this option to force global invalidations to be done via
+ IPIs unconditionally.
+
config PPC_KERNEL_PREFIXED
depends on PPC_HAVE_PREFIXED_SUPPORT
depends on CC_HAS_PREFIXED
diff --git a/arch/powerpc/platforms/microwatt/Kconfig
b/arch/powerpc/platforms/microwatt/Kconfig
index 5e41adadac1f..1d5cc1ae3636 100644
--- a/arch/powerpc/platforms/microwatt/Kconfig
+++ b/arch/powerpc/platforms/microwatt/Kconfig
@@ -7,6 +7,7 @@ config PPC_MICROWATT
select PPC_ICP_NATIVE
select PPC_UDBG_16550
select COMMON_CLK
+ select PPC_RADIX_NO_BROADCAST_TLBIE
help
This option enables support for FPGA-based Microwatt implementations.
--
2.47.1
