[PATCH 07/12] MIPS: smp-cps: don't run MT instructions if cpu doesn't have MT

[Paul Burton <paul.burton@xxxxxxxxxx>]

The code already checked for MT in most cases but executed dmt
instructions regardless of whether the CPU implements the MT ASE. This
would lead to a reserved instruction exception on those which do not.

Signed-off-by: Paul Burton <paul.burton@xxxxxxxxxx>
---
Feel free to apply this as a fixup to "MIPS: Coherent Processing System
SMP implementation".
---
 arch/mips/kernel/smp-cps.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/arch/mips/kernel/smp-cps.c b/arch/mips/kernel/smp-cps.c
index 4b812c1..536eec0 100644
--- a/arch/mips/kernel/smp-cps.c
+++ b/arch/mips/kernel/smp-cps.c
@@ -141,7 +141,8 @@ static void __init cps_smp_setup(void)
 	bitmap_set(core_power, 0, 1);
 
 	/* Disable MT - we only want to run 1 TC per VPE */
-	dmt();
+	if (cpu_has_mipsmt)
+		dmt();
 
 	/* Initialise core 0 */
 	init_core();
@@ -268,6 +269,8 @@ static void cps_boot_secondary(int cpu, struct task_struct *idle)
 		return;
 	}
 
+	BUG_ON(!cpu_has_mipsmt);
+
 	/* Boot a VPE on this core */
 	boot_vpe(&cfg);
 }
@@ -275,7 +278,8 @@ static void cps_boot_secondary(int cpu, struct task_struct *idle)
 static void cps_init_secondary(void)
 {
 	/* Disable MT - we only want to run 1 TC per VPE */
-	dmt();
+	if (cpu_has_mipsmt)
+		dmt();
 
 	/* TODO: revisit this assumption once hotplug is implemented */
 	if (cpu_vpe_id(&current_cpu_data) == 0)
-- 
1.8.5.3