In ultravisor enabled systems, PTCR becomes ultravisor privileged only
for writing and an attempt to write to it will cause a Hypervisor
Emulation Assitance interrupt.
This patch adds the try_set_ptcr(val) macro as an accessor to
mtspr(SPRN_PTCR, val), which will be executed only if ultravisor
disabled.
Signed-off-by: Claudio Carvalho <cclau...@linux.ibm.com>
---
arch/powerpc/include/asm/reg.h | 13 +++++++++++++
arch/powerpc/mm/book3s64/hash_utils.c | 4 ++--
arch/powerpc/mm/book3s64/pgtable.c | 2 +-
arch/powerpc/mm/book3s64/radix_pgtable.c | 6 +++---
4 files changed, 19 insertions(+), 6 deletions(-)
diff --git a/arch/powerpc/include/asm/reg.h b/arch/powerpc/include/asm/reg.h
index 10caa145f98b..14139b1ebdb8 100644
--- a/arch/powerpc/include/asm/reg.h
+++ b/arch/powerpc/include/asm/reg.h
@@ -15,6 +15,7 @@
#include <asm/cputable.h>
#include <asm/asm-const.h>
#include <asm/feature-fixups.h>
+#include <asm/firmware.h>
/* Pickup Book E specific registers. */
#if defined(CONFIG_BOOKE) || defined(CONFIG_40x)
@@ -1452,6 +1453,18 @@ static inline void update_power8_hid0(unsigned long hid0)
*/
asm volatile("sync; mtspr %0,%1; isync":: "i"(SPRN_HID0), "r"(hid0));
}
+
+/*
+ * In ultravisor enabled systems, PTCR becomes ultravisor privileged only for
+ * writing and an attempt to write to it will cause a Hypervisor Emulation
+ * Assistance interrupt.
+ */
+#define try_set_ptcr(val) \
+ do { \
+ if (!firmware_has_feature(FW_FEATURE_ULTRAVISOR)) \
+ mtspr(SPRN_PTCR, val); \
+ } while (0)
+
#endif /* __ASSEMBLY__ */
#endif /* __KERNEL__ */
#endif /* _ASM_POWERPC_REG_H */
diff --git a/arch/powerpc/mm/book3s64/hash_utils.c
b/arch/powerpc/mm/book3s64/hash_utils.c
index 25a2cf32d544..048b7f58deae 100644
--- a/arch/powerpc/mm/book3s64/hash_utils.c
+++ b/arch/powerpc/mm/book3s64/hash_utils.c
@@ -1079,8 +1079,8 @@ void hash__early_init_mmu_secondary(void)
if (!cpu_has_feature(CPU_FTR_ARCH_300))
mtspr(SPRN_SDR1, _SDR1);
else
- mtspr(SPRN_PTCR,
- __pa(partition_tb) | (PATB_SIZE_SHIFT - 12));
+ try_set_ptcr(__pa(partition_tb) |
+ (PATB_SIZE_SHIFT - 12));
}
/* Initialize SLB */
slb_initialize();
diff --git a/arch/powerpc/mm/book3s64/pgtable.c
b/arch/powerpc/mm/book3s64/pgtable.c
index 033731f5dbaa..016c6ccb5b81 100644
--- a/arch/powerpc/mm/book3s64/pgtable.c
+++ b/arch/powerpc/mm/book3s64/pgtable.c
@@ -219,7 +219,7 @@ void __init mmu_partition_table_init(void)
* 64 K size.
*/
ptcr = __pa(partition_tb) | (PATB_SIZE_SHIFT - 12);
- mtspr(SPRN_PTCR, ptcr);
+ try_set_ptcr(ptcr);
powernv_set_nmmu_ptcr(ptcr);
}
diff --git a/arch/powerpc/mm/book3s64/radix_pgtable.c
b/arch/powerpc/mm/book3s64/radix_pgtable.c
index e92c6472a20c..246b32550eab 100644
--- a/arch/powerpc/mm/book3s64/radix_pgtable.c
+++ b/arch/powerpc/mm/book3s64/radix_pgtable.c
@@ -654,8 +654,8 @@ void radix__early_init_mmu_secondary(void)
lpcr = mfspr(SPRN_LPCR);
mtspr(SPRN_LPCR, lpcr | LPCR_UPRT | LPCR_HR);
- mtspr(SPRN_PTCR,
- __pa(partition_tb) | (PATB_SIZE_SHIFT - 12));
+ try_set_ptcr(__pa(partition_tb) | (PATB_SIZE_SHIFT - 12));
+
radix_init_amor();
}
@@ -671,7 +671,7 @@ void radix__mmu_cleanup_all(void)
if (!firmware_has_feature(FW_FEATURE_LPAR)) {
lpcr = mfspr(SPRN_LPCR);
mtspr(SPRN_LPCR, lpcr & ~LPCR_UPRT);
- mtspr(SPRN_PTCR, 0);
+ try_set_ptcr(0);
powernv_set_nmmu_ptcr(0);
radix__flush_tlb_all();
}
--
2.20.1
