We don't know how to do coherence setup on ISA before MIPS
Release 1.
As CPS support only servers simulation purpose on those cores,
and simulators are always coherent, just disable initialization
code and provide user a warning in case coherence is not setup
properly.
Signed-off-by: Jiaxun Yang <jiaxun.yang@xxxxxxxxxxx>
---
arch/mips/kernel/cps-vec.S | 5 +++++
arch/mips/kernel/smp-cps.c | 5 +++++
2 files changed, 10 insertions(+)
diff --git a/arch/mips/kernel/cps-vec.S b/arch/mips/kernel/cps-vec.S
index 8ef492da827f..64ecfdac6580 100644
--- a/arch/mips/kernel/cps-vec.S
+++ b/arch/mips/kernel/cps-vec.S
@@ -116,6 +116,8 @@ not_nmi:
li t0, ST0_CU1 | ST0_CU0 | ST0_BEV | STATUS_BITDEPS
mtc0 t0, CP0_STATUS
+ /* We don't know how to do coherence setup on earlier ISA */
+#if MIPS_ISA_REV > 0
/* Skip cache & coherence setup if we're already coherent */
lw s7, GCR_CL_COHERENCE_OFS(s1)
bnez s7, 1f
@@ -129,6 +131,7 @@ not_nmi:
li t0, 0xff
sw t0, GCR_CL_COHERENCE_OFS(s1)
ehb
+#endif /* MIPS_ISA_REV > 0 */
/* Set Kseg0 CCA to that in s0 */
1: mfc0 t0, CP0_CONFIG
@@ -515,6 +518,7 @@ LEAF(mips_cps_boot_vpes)
nop
END(mips_cps_boot_vpes)
+#if MIPS_ISA_REV > 0
LEAF(mips_cps_cache_init)
/*
* Clear the bits used to index the caches. Note that the architecture
@@ -588,6 +592,7 @@ dcache_done:
jr ra
nop
END(mips_cps_cache_init)
+#endif /* MIPS_ISA_REV > 0 */
#if defined(CONFIG_MIPS_CPS_PM) && defined(CONFIG_CPU_PM)
diff --git a/arch/mips/kernel/smp-cps.c b/arch/mips/kernel/smp-cps.c
index 4fc288bb85b9..f968a319d87f 100644
--- a/arch/mips/kernel/smp-cps.c
+++ b/arch/mips/kernel/smp-cps.c
@@ -361,6 +361,8 @@ static int cps_boot_secondary(int cpu, struct task_struct *idle)
static void cps_init_secondary(void)
{
+ int core = cpu_core(¤t_cpu_data);
+
/* Disable MT - we only want to run 1 TC per VPE */
if (cpu_has_mipsmt)
dmt();
@@ -376,6 +378,9 @@ static void cps_init_secondary(void)
BUG_ON(ident != mips_cm_vp_id(smp_processor_id()));
}
+ if (core > 0 && !read_gcr_cl_coherence())
+ pr_warn("Core %u is not in coherent domain\n", core);
+
if (cpu_has_veic)
clear_c0_status(ST0_IM);
else
--
2.37.1 (Apple Git-137.1)
