Subject: [PATCH 4/6] powerpc/64s/pseries: radix flush translations before MMU is enabled at boot

From: Nicholas Piggin <[email-masked]>
Date: Tue, 3 Sep 2019 01:29:29 +1000

Radix guests are responsible for managing their own translation caches,
so make them match bare metal radix and hash, and make each CPU flush
all its translations right before enabling its MMU.

Radix guests may not flush partition scope translations, so in
tlbiel_all, make these flushes conditional on CPU_FTR_HVMODE. Process
scope translations are the only type visible to the guest.

Signed-off-by: Nicholas Piggin <[email-masked]>
---
 arch/powerpc/mm/book3s64/radix_pgtable.c |  6 ++----
 arch/powerpc/mm/book3s64/radix_tlb.c     | 12 ++++++++----
 2 files changed, 10 insertions(+), 8 deletions(-)

diff --git a/arch/powerpc/mm/book3s64/radix_pgtable.c b/arch/powerpc/mm/book3s64/radix_pgtable.c
index 078a7eeec1f5..e1e711c4704a 100644
--- a/arch/powerpc/mm/book3s64/radix_pgtable.c
+++ b/arch/powerpc/mm/book3s64/radix_pgtable.c
@@ -616,8 +616,7 @@ void __init radix__early_init_mmu(void)
 
 	/* Switch to the guard PID before turning on MMU */
 	radix__switch_mmu_context(NULL, &init_mm);
-	if (cpu_has_feature(CPU_FTR_HVMODE))
-		tlbiel_all();
+	tlbiel_all();
 }
 
 void radix__early_init_mmu_secondary(void)
@@ -637,8 +636,7 @@ void radix__early_init_mmu_secondary(void)
 	}
 
 	radix__switch_mmu_context(NULL, &init_mm);
-	if (cpu_has_feature(CPU_FTR_HVMODE))
-		tlbiel_all();
+	tlbiel_all();
 }
 
 void radix__mmu_cleanup_all(void)
diff --git a/arch/powerpc/mm/book3s64/radix_tlb.c b/arch/powerpc/mm/book3s64/radix_tlb.c
index 082f90d068ee..f9cf8ae59831 100644
--- a/arch/powerpc/mm/book3s64/radix_tlb.c
+++ b/arch/powerpc/mm/book3s64/radix_tlb.c
@@ -51,11 +51,15 @@ static void tlbiel_all_isa300(unsigned int num_sets, unsigned int is)
 	 * and partition table entries. Then flush the remaining sets of the
 	 * TLB.
 	 */
-	tlbiel_radix_set_isa300(0, is, 0, RIC_FLUSH_ALL, 0);
-	for (set = 1; set < num_sets; set++)
-		tlbiel_radix_set_isa300(set, is, 0, RIC_FLUSH_TLB, 0);
 
-	/* Do the same for process scoped entries. */
+	if (early_cpu_has_feature(CPU_FTR_HVMODE)) {
+		/* MSR[HV] should flush partition scope translations first. */
+		tlbiel_radix_set_isa300(0, is, 0, RIC_FLUSH_ALL, 0);
+		for (set = 1; set < num_sets; set++)
+			tlbiel_radix_set_isa300(set, is, 0, RIC_FLUSH_TLB, 0);
+	}
+
+	/* Flush process scoped entries. */
 	tlbiel_radix_set_isa300(0, is, 0, RIC_FLUSH_ALL, 1);
 	for (set = 1; set < num_sets; set++)
 		tlbiel_radix_set_isa300(set, is, 0, RIC_FLUSH_TLB, 1);
-- 
2.22.0