Commit 79f4bb17 authored by Christophe Leroy's avatar Christophe Leroy Committed by Michael Ellerman
Browse files

powerpc/32: Handle bookE debugging in C in exception entry 



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

Signed-off-by: default avatarChristophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/6d6b2497115890b90cfa72a2b3ab1da5f78123c2.1615552866.git.christophe.leroy@csgroup.eu
parent f93d866e

arch/powerpc/include/asm/interrupt.h

+2 −0
Original line number Diff line number Diff line
@@ -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();

}



/*

arch/powerpc/kernel/entry_32.S

+0 −23
Original line number Diff line number Diff line
@@ -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