From patchwork Sat Nov 30 06:32:27 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Vijay Kilari X-Patchwork-Id: 3260021 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 7DA719F377 for ; Sat, 30 Nov 2013 06:36:08 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 5FB29205C2 for ; Sat, 30 Nov 2013 06:36:07 +0000 (UTC) Received: from casper.infradead.org (casper.infradead.org [85.118.1.10]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 5B5FD2054E for ; Sat, 30 Nov 2013 06:36:06 +0000 (UTC) Received: from merlin.infradead.org ([2001:4978:20e::2]) by casper.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1Vme8s-0007NU-VO; Sat, 30 Nov 2013 06:35:04 +0000 Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1Vme8b-0006V6-At; Sat, 30 Nov 2013 06:34:45 +0000 Received: from mail-pd0-x236.google.com ([2607:f8b0:400e:c02::236]) by merlin.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1Vme8D-0006QY-Cq for linux-arm-kernel@lists.infradead.org; Sat, 30 Nov 2013 06:34:23 +0000 Received: by mail-pd0-f182.google.com with SMTP id v10so14943139pde.27 for ; Fri, 29 Nov 2013 22:33:59 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=dyqjHw4sCj7DLVO9m33rOhqqM3vByc2uqyAkXngO9Hg=; b=x4NhUc2ulu7TK37qpBu8Vq7+X43B/Su6QwlyHM9VomH73HPs6iHQVp+9p5vvAqizdm xhqB6AyMAD7j5s2Q/56pa99vO/UNlI0EJRmsdx64Vw5QLyvTKKyGAXqcIFoeLe3zLrYu 2Xb5w1HXam7ojeqXyBBK2oaUx+m4bfVmEh/w+hI/wFZ1yPlh/cBolrNF8sP1aZlzqkff tSiM9MjcC+9fIQFVeHWnsK8jQbpsCcviupm0Dsujv7rtDOaftwiLvKlh/2QHBuCSMYZC Vy5dcj92zC9z7yQGSsQY8KhFh3F0q7Q0+PKsFqAsNiAD2txThNapjZ1D1koQkRyfrrwb hEzQ== X-Received: by 10.66.171.13 with SMTP id aq13mr56245891pac.30.1385793239646; Fri, 29 Nov 2013 22:33:59 -0800 (PST) Received: from ubuntu.caveonetworks.com ([115.119.134.194]) by mx.google.com with ESMTPSA id km1sm14800759pbd.13.2013.11.29.22.33.56 for (version=TLSv1.1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Fri, 29 Nov 2013 22:33:59 -0800 (PST) From: vijay.kilari@gmail.com To: will.deacon@arm.com, sandeepa.prabhu@linaro.org, jason.wessel@windriver.com, takahiro.akashi@linaro.org, Catalin.Marinas@arm.com Subject: [PATCH v5 3/4] AArch64: KGDB: Add step debugging support Date: Sat, 30 Nov 2013 12:02:27 +0530 Message-Id: <1385793148-28979-4-git-send-email-vijay.kilari@gmail.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1385793148-28979-1-git-send-email-vijay.kilari@gmail.com> References: <1385793148-28979-1-git-send-email-vijay.kilari@gmail.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20131130_013421_625144_6ACBA25C X-CRM114-Status: GOOD ( 17.26 ) X-Spam-Score: -2.0 (--) Cc: Prasun.Kapoor@caviumnetworks.com, Vijaya Kumar K , linaro-kernel@lists.linaro.org, linux@arm.linux.org.uk, linux-arm-kernel@lists.infradead.org X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-4.1 required=5.0 tests=BAYES_00, DKIM_ADSP_CUSTOM_MED, DKIM_SIGNED, FREEMAIL_FROM, RCVD_IN_DNSWL_MED, RP_MATCHES_RCVD, T_DKIM_INVALID, UNPARSEABLE_RELAY autolearn=ham version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Vijaya Kumar K Add KGDB software step debugging support for EL1 debug in AArch64 mode. KGDB registers step debug handler with debug monitor. On receiving 'step' command from GDB tool, target enables software step debugging and step address is updated in ELR. Software Step debugging is disabled when 'continue' command is received Signed-off-by: Vijaya Kumar K Reviewed-by: Will Deacon --- arch/arm64/kernel/kgdb.c | 67 +++++++++++++++++++++++++++++++++++++++------- 1 file changed, 58 insertions(+), 9 deletions(-) diff --git a/arch/arm64/kernel/kgdb.c b/arch/arm64/kernel/kgdb.c index ec624bc..f10f2ba 100644 --- a/arch/arm64/kernel/kgdb.c +++ b/arch/arm64/kernel/kgdb.c @@ -137,13 +137,26 @@ void kgdb_arch_set_pc(struct pt_regs *regs, unsigned long pc) static int compiled_break; +static void kgdb_arch_update_addr(struct pt_regs *regs, + char *remcom_in_buffer) +{ + unsigned long addr; + char *ptr; + + ptr = &remcom_in_buffer[1]; + if (kgdb_hex2long(&ptr, &addr)) + kgdb_arch_set_pc(regs, addr); + else if (compiled_break == 1) + kgdb_arch_set_pc(regs, regs->pc + 4); + + compiled_break = 0; +} + int kgdb_arch_handle_exception(int exception_vector, int signo, int err_code, char *remcom_in_buffer, char *remcom_out_buffer, struct pt_regs *linux_regs) { - unsigned long addr; - char *ptr; int err; switch (remcom_in_buffer[0]) { @@ -153,6 +166,8 @@ int kgdb_arch_handle_exception(int exception_vector, int signo, * Packet D (Detach), k (kill). No special handling * is required here */ + atomic_set(&kgdb_cpu_doing_single_step, -1); + kgdb_single_step = 0; err = 0; break; case 'c': @@ -164,16 +179,39 @@ int kgdb_arch_handle_exception(int exception_vector, int signo, * to the next instruction else we will just breakpoint * over and over again. */ - ptr = &remcom_in_buffer[1]; - if (kgdb_hex2long(&ptr, &addr)) - kgdb_arch_set_pc(linux_regs, addr); - else if (compiled_break == 1) - kgdb_arch_set_pc(linux_regs, linux_regs->pc + 4); + kgdb_arch_update_addr(linux_regs, remcom_in_buffer); + atomic_set(&kgdb_cpu_doing_single_step, -1); + kgdb_single_step = 0; - compiled_break = 0; + /* + * Received continue command, disable single step + */ + if (kernel_active_single_step()) + kernel_disable_single_step(); err = 0; break; + case 's': + /* + * Update step address value with address passed + * with step packet. + * On debug exception return PC is copied to ELR + * So just update PC. + * If no step address is passed, resume from the address + * pointed by PC. Do not update PC + */ + kgdb_arch_update_addr(linux_regs, remcom_in_buffer); + atomic_set(&kgdb_cpu_doing_single_step, raw_smp_processor_id()); + kgdb_single_step = 1; + + /* + * Enable single step handling + */ + if (!kernel_active_single_step()) + kernel_enable_single_step(linux_regs); + err = 0; + break; + default: err = -1; } @@ -194,6 +232,12 @@ static int kgdb_compiled_brk_fn(struct pt_regs *regs, unsigned int esr) return 0; } +static int kgdb_step_brk_fn(struct pt_regs *regs, unsigned int esr) +{ + kgdb_handle_exception(1, SIGTRAP, 0, regs); + return 0; +} + static struct break_hook kgdb_brkpt_hook = { .esr_mask = 0xffffffff, .esr_val = DBG_ESR_VAL_BRK(KGDB_DYN_DGB_BRK_IMM), @@ -206,6 +250,10 @@ static struct break_hook kgdb_compiled_brkpt_hook = { .fn = kgdb_compiled_brk_fn }; +static struct step_hook kgdb_step_hook = { + .fn = kgdb_step_brk_fn +}; + static void kgdb_call_nmi_hook(void *ignored) { kgdb_nmicallback(raw_smp_processor_id(), get_irq_regs()); @@ -259,7 +307,7 @@ int kgdb_arch_init(void) register_break_hook(&kgdb_brkpt_hook); register_break_hook(&kgdb_compiled_brkpt_hook); - + register_step_hook(&kgdb_step_hook); return 0; } @@ -272,6 +320,7 @@ void kgdb_arch_exit(void) { unregister_break_hook(&kgdb_brkpt_hook); unregister_break_hook(&kgdb_compiled_brkpt_hook); + unregister_step_hook(&kgdb_step_hook); unregister_die_notifier(&kgdb_notifier); }