From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754032AbcHRJoZ (ORCPT ); Thu, 18 Aug 2016 05:44:25 -0400 Received: from pegase1.c-s.fr ([93.17.236.30]:50380 "EHLO pegase1.c-s.fr" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753878AbcHRJoX (ORCPT ); Thu, 18 Aug 2016 05:44:23 -0400 From: Christophe Leroy Subject: [PATCH] powerpc/8xx: fix single_step debug To: Benjamin Herrenschmidt , Paul Mackerras , Michael Ellerman , Scott Wood Cc: linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org Message-Id: <20160818094420.8E0991A2459@localhost.localdomain> Date: Thu, 18 Aug 2016 11:44:20 +0200 (CEST) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org SPRN_ICR must be read for clearing the internal freeze signal which is asserted by the single step exception, otherwise the timebase and decrementer remain freezed Signed-off-by: Christophe Leroy --- arch/powerpc/include/asm/reg_8xx.h | 1 + arch/powerpc/kernel/traps.c | 8 ++++++++ 2 files changed, 9 insertions(+) diff --git a/arch/powerpc/include/asm/reg_8xx.h b/arch/powerpc/include/asm/reg_8xx.h index feaf641..6dae71f 100644 --- a/arch/powerpc/include/asm/reg_8xx.h +++ b/arch/powerpc/include/asm/reg_8xx.h @@ -17,6 +17,7 @@ #define SPRN_DC_DAT 570 /* Read-only data register */ /* Misc Debug */ +#define SPRN_ICR 148 #define SPRN_DPDR 630 #define SPRN_MI_CAM 816 #define SPRN_MI_RAM0 817 diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c index 2cb5892..0f1f0ce 100644 --- a/arch/powerpc/kernel/traps.c +++ b/arch/powerpc/kernel/traps.c @@ -400,8 +400,16 @@ static inline int check_io_access(struct pt_regs *regs) #define REASON_TRAP 0x20000 #define single_stepping(regs) ((regs)->msr & MSR_SE) +#ifdef CONFIG_PPC_8xx +static inline void clear_single_step(struct pt_regs *regs) +{ + regs->msr &= ~MSR_SE; + mfspr(SPRN_ICR); +} +#else #define clear_single_step(regs) ((regs)->msr &= ~MSR_SE) #endif +#endif #if defined(CONFIG_4xx) int machine_check_4xx(struct pt_regs *regs) -- 2.1.0