[PATCH v2 11/43] powerpc/32: Handle bookE debugging in C in exception entry

From: Christophe Leroy
Date: Tue Mar 09 2021 - 07:10:37 EST


The handling of SPRN_DBCR0 and other registers can easily
be done in C instead of ASM.

Signed-off-by: Christophe Leroy <christophe.leroy@xxxxxxxxxx>
---
arch/powerpc/include/asm/interrupt.h | 2 ++
arch/powerpc/kernel/entry_32.S | 23 -----------------------
2 files changed, 2 insertions(+), 23 deletions(-)

diff --git a/arch/powerpc/include/asm/interrupt.h b/arch/powerpc/include/asm/interrupt.h
index c35368adbe71..861e6eadc98c 100644
--- a/arch/powerpc/include/asm/interrupt.h
+++ b/arch/powerpc/include/asm/interrupt.h
@@ -65,6 +65,8 @@ static inline void interrupt_enter_prepare(struct pt_regs *regs, struct interrup
if (user_mode(regs))
account_cpu_user_entry();
#endif
+
+ booke_restore_dbcr0();
}

/*
diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S
index 0f3f1bdd909e..4ffbcf3df72e 100644
--- a/arch/powerpc/kernel/entry_32.S
+++ b/arch/powerpc/kernel/entry_32.S
@@ -146,32 +146,9 @@ transfer_to_handler:
addi r2, r12, -THREAD
addi r11,r1,STACK_FRAME_OVERHEAD
stw r11,PT_REGS(r12)
-#if defined(CONFIG_40x) || defined(CONFIG_BOOKE)
- /* Check to see if the dbcr0 register is set up to debug. Use the
- internal debug mode bit to do this. */
- lwz r12,THREAD_DBCR0(r12)
- andis. r12,r12,DBCR0_IDM@h
-#endif
#ifdef CONFIG_PPC_BOOK3S_32
kuep_lock r11, r12
#endif
-#if defined(CONFIG_40x) || defined(CONFIG_BOOKE)
- beq+ 3f
- /* From user and task is ptraced - load up global dbcr0 */
- li r12,-1 /* clear all pending debug events */
- mtspr SPRN_DBSR,r12
- lis r11,global_dbcr0@ha
- tophys_novmstack r11,r11
- addi r11,r11,global_dbcr0@l
-#ifdef CONFIG_SMP
- lwz r9,TASK_CPU(r2)
- slwi r9,r9,2
- add r11,r11,r9
-#endif
- lwz r12,0(r11)
- mtspr SPRN_DBCR0,r12
-#endif
-
b 3f

2: /* if from kernel, check interrupted DOZE/NAP mode and
--
2.25.0