[PATCH 5.2 387/413] powerpc/32s: fix suspend/resume when IBATs 4-7 are used

From: Greg Kroah-Hartman
Date: Wed Jul 24 2019 - 15:43:01 EST

From: Christophe Leroy <christophe.leroy@xxxxxx>

commit 6ecb78ef56e08d2119d337ae23cb951a640dc52d upstream.

Previously, only IBAT1 and IBAT2 were used to map kernel linear mem.
Since commit 63b2bc619565 ("powerpc/mm/32s: Use BATs for
STRICT_KERNEL_RWX"), we may have all 8 BATs used for mapping
kernel text. But the suspend/restore functions only save/restore
BATs 0 to 3, and clears BATs 4 to 7.

Make suspend and restore functions respectively save and reload
the 8 BATs on CPUs having MMU_FTR_USE_HIGH_BATS feature.

Reported-by: Andreas Schwab <schwab@xxxxxxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Christophe Leroy <christophe.leroy@xxxxxx>
Signed-off-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
arch/powerpc/kernel/swsusp_32.S | 73 ++++++++++++++++++++++++++++----
arch/powerpc/platforms/powermac/sleep.S | 68 +++++++++++++++++++++++++++--
2 files changed, 128 insertions(+), 13 deletions(-)

--- a/arch/powerpc/kernel/swsusp_32.S
+++ b/arch/powerpc/kernel/swsusp_32.S
@@ -25,11 +25,19 @@
#define SL_IBAT2 0x48
#define SL_DBAT3 0x50
#define SL_IBAT3 0x58
-#define SL_TB 0x60
-#define SL_R2 0x68
-#define SL_CR 0x6c
-#define SL_LR 0x70
-#define SL_R12 0x74 /* r12 to r31 */
+#define SL_DBAT4 0x60
+#define SL_IBAT4 0x68
+#define SL_DBAT5 0x70
+#define SL_IBAT5 0x78
+#define SL_DBAT6 0x80
+#define SL_IBAT6 0x88
+#define SL_DBAT7 0x90
+#define SL_IBAT7 0x98
+#define SL_TB 0xa0
+#define SL_R2 0xa8
+#define SL_CR 0xac
+#define SL_LR 0xb0
+#define SL_R12 0xb4 /* r12 to r31 */
#define SL_SIZE (SL_R12 + 80)

.section .data
@@ -114,6 +122,41 @@ _GLOBAL(swsusp_arch_suspend)
mfibatl r4,3
stw r4,SL_IBAT3+4(r11)

+BEGIN_MMU_FTR_SECTION
+ mfspr r4,SPRN_DBAT4U
+ stw r4,SL_DBAT4(r11)
+ mfspr r4,SPRN_DBAT4L
+ stw r4,SL_DBAT4+4(r11)
+ mfspr r4,SPRN_DBAT5U
+ stw r4,SL_DBAT5(r11)
+ mfspr r4,SPRN_DBAT5L
+ stw r4,SL_DBAT5+4(r11)
+ mfspr r4,SPRN_DBAT6U
+ stw r4,SL_DBAT6(r11)
+ mfspr r4,SPRN_DBAT6L
+ stw r4,SL_DBAT6+4(r11)
+ mfspr r4,SPRN_DBAT7U
+ stw r4,SL_DBAT7(r11)
+ mfspr r4,SPRN_DBAT7L
+ stw r4,SL_DBAT7+4(r11)
+ mfspr r4,SPRN_IBAT4U
+ stw r4,SL_IBAT4(r11)
+ mfspr r4,SPRN_IBAT4L
+ stw r4,SL_IBAT4+4(r11)
+ mfspr r4,SPRN_IBAT5U
+ stw r4,SL_IBAT5(r11)
+ mfspr r4,SPRN_IBAT5L
+ stw r4,SL_IBAT5+4(r11)
+ mfspr r4,SPRN_IBAT6U
+ stw r4,SL_IBAT6(r11)
+ mfspr r4,SPRN_IBAT6L
+ stw r4,SL_IBAT6+4(r11)
+ mfspr r4,SPRN_IBAT7U
+ stw r4,SL_IBAT7(r11)
+ mfspr r4,SPRN_IBAT7L
+ stw r4,SL_IBAT7+4(r11)
+END_MMU_FTR_SECTION_IFSET(MMU_FTR_USE_HIGH_BATS)
+
#if 0
/* Backup various CPU config stuffs */
bl __save_cpu_setup
@@ -279,27 +322,41 @@ END_FTR_SECTION_IFSET(CPU_FTR_ALTIVEC)
mtibatu 3,r4
lwz r4,SL_IBAT3+4(r11)
mtibatl 3,r4
-#endif
-
BEGIN_MMU_FTR_SECTION
- li r4,0
+ lwz r4,SL_DBAT4(r11)
mtspr SPRN_DBAT4U,r4
+ lwz r4,SL_DBAT4+4(r11)
mtspr SPRN_DBAT4L,r4
+ lwz r4,SL_DBAT5(r11)
mtspr SPRN_DBAT5U,r4
+ lwz r4,SL_DBAT5+4(r11)
mtspr SPRN_DBAT5L,r4
+ lwz r4,SL_DBAT6(r11)
mtspr SPRN_DBAT6U,r4
+ lwz r4,SL_DBAT6+4(r11)
mtspr SPRN_DBAT6L,r4
+ lwz r4,SL_DBAT7(r11)
mtspr SPRN_DBAT7U,r4
+ lwz r4,SL_DBAT7+4(r11)
mtspr SPRN_DBAT7L,r4
+ lwz r4,SL_IBAT4(r11)
mtspr SPRN_IBAT4U,r4
+ lwz r4,SL_IBAT4+4(r11)
mtspr SPRN_IBAT4L,r4
+ lwz r4,SL_IBAT5(r11)
mtspr SPRN_IBAT5U,r4
+ lwz r4,SL_IBAT5+4(r11)
mtspr SPRN_IBAT5L,r4
+ lwz r4,SL_IBAT6(r11)
mtspr SPRN_IBAT6U,r4
+ lwz r4,SL_IBAT6+4(r11)
mtspr SPRN_IBAT6L,r4
+ lwz r4,SL_IBAT7(r11)
mtspr SPRN_IBAT7U,r4
+ lwz r4,SL_IBAT7+4(r11)
mtspr SPRN_IBAT7L,r4
END_MMU_FTR_SECTION_IFSET(MMU_FTR_USE_HIGH_BATS)
+#endif

/* Flush all TLBs */
lis r4,0x1000
--- a/arch/powerpc/platforms/powermac/sleep.S
+++ b/arch/powerpc/platforms/powermac/sleep.S
@@ -33,10 +33,18 @@
#define SL_IBAT2 0x48
#define SL_DBAT3 0x50
#define SL_IBAT3 0x58
-#define SL_TB 0x60
-#define SL_R2 0x68
-#define SL_CR 0x6c
-#define SL_R12 0x70 /* r12 to r31 */
+#define SL_DBAT4 0x60
+#define SL_IBAT4 0x68
+#define SL_DBAT5 0x70
+#define SL_IBAT5 0x78
+#define SL_DBAT6 0x80
+#define SL_IBAT6 0x88
+#define SL_DBAT7 0x90
+#define SL_IBAT7 0x98
+#define SL_TB 0xa0
+#define SL_R2 0xa8
+#define SL_CR 0xac
+#define SL_R12 0xb0 /* r12 to r31 */
#define SL_SIZE (SL_R12 + 80)

.section .text
@@ -121,6 +129,41 @@ _GLOBAL(low_sleep_handler)
mfibatl r4,3
stw r4,SL_IBAT3+4(r1)

+BEGIN_MMU_FTR_SECTION
+ mfspr r4,SPRN_DBAT4U
+ stw r4,SL_DBAT4(r1)
+ mfspr r4,SPRN_DBAT4L
+ stw r4,SL_DBAT4+4(r1)
+ mfspr r4,SPRN_DBAT5U
+ stw r4,SL_DBAT5(r1)
+ mfspr r4,SPRN_DBAT5L
+ stw r4,SL_DBAT5+4(r1)
+ mfspr r4,SPRN_DBAT6U
+ stw r4,SL_DBAT6(r1)
+ mfspr r4,SPRN_DBAT6L
+ stw r4,SL_DBAT6+4(r1)
+ mfspr r4,SPRN_DBAT7U
+ stw r4,SL_DBAT7(r1)
+ mfspr r4,SPRN_DBAT7L
+ stw r4,SL_DBAT7+4(r1)
+ mfspr r4,SPRN_IBAT4U
+ stw r4,SL_IBAT4(r1)
+ mfspr r4,SPRN_IBAT4L
+ stw r4,SL_IBAT4+4(r1)
+ mfspr r4,SPRN_IBAT5U
+ stw r4,SL_IBAT5(r1)
+ mfspr r4,SPRN_IBAT5L
+ stw r4,SL_IBAT5+4(r1)
+ mfspr r4,SPRN_IBAT6U
+ stw r4,SL_IBAT6(r1)
+ mfspr r4,SPRN_IBAT6L
+ stw r4,SL_IBAT6+4(r1)
+ mfspr r4,SPRN_IBAT7U
+ stw r4,SL_IBAT7(r1)
+ mfspr r4,SPRN_IBAT7L
+ stw r4,SL_IBAT7+4(r1)
+END_MMU_FTR_SECTION_IFSET(MMU_FTR_USE_HIGH_BATS)
+
/* Backup various CPU config stuffs */
bl __save_cpu_setup

@@ -321,22 +364,37 @@ grackle_wake_up:
mtibatl 3,r4

BEGIN_MMU_FTR_SECTION
- li r4,0
+ lwz r4,SL_DBAT4(r1)
mtspr SPRN_DBAT4U,r4
+ lwz r4,SL_DBAT4+4(r1)
mtspr SPRN_DBAT4L,r4
+ lwz r4,SL_DBAT5(r1)
mtspr SPRN_DBAT5U,r4
+ lwz r4,SL_DBAT5+4(r1)
mtspr SPRN_DBAT5L,r4
+ lwz r4,SL_DBAT6(r1)
mtspr SPRN_DBAT6U,r4
+ lwz r4,SL_DBAT6+4(r1)
mtspr SPRN_DBAT6L,r4
+ lwz r4,SL_DBAT7(r1)
mtspr SPRN_DBAT7U,r4
+ lwz r4,SL_DBAT7+4(r1)
mtspr SPRN_DBAT7L,r4
+ lwz r4,SL_IBAT4(r1)
mtspr SPRN_IBAT4U,r4
+ lwz r4,SL_IBAT4+4(r1)
mtspr SPRN_IBAT4L,r4
+ lwz r4,SL_IBAT5(r1)
mtspr SPRN_IBAT5U,r4
+ lwz r4,SL_IBAT5+4(r1)
mtspr SPRN_IBAT5L,r4
+ lwz r4,SL_IBAT6(r1)
mtspr SPRN_IBAT6U,r4
+ lwz r4,SL_IBAT6+4(r1)
mtspr SPRN_IBAT6L,r4
+ lwz r4,SL_IBAT7(r1)
mtspr SPRN_IBAT7U,r4
+ lwz r4,SL_IBAT7+4(r1)
mtspr SPRN_IBAT7L,r4
END_MMU_FTR_SECTION_IFSET(MMU_FTR_USE_HIGH_BATS)