From patchwork Fri Oct 18 11:07:48 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Vijay Kilari X-Patchwork-Id: 3065771 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 643019F243 for ; Fri, 18 Oct 2013 11:11:20 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 3569E20116 for ; Fri, 18 Oct 2013 11:11:19 +0000 (UTC) Received: from casper.infradead.org (casper.infradead.org [85.118.1.10]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id DCAB12037F for ; Fri, 18 Oct 2013 11:11:17 +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 1VX7wJ-0004z9-B2; Fri, 18 Oct 2013 11:09:57 +0000 Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1VX7vs-0007go-Do; Fri, 18 Oct 2013 11:09:28 +0000 Received: from mail-pd0-x230.google.com ([2607:f8b0:400e:c02::230]) by merlin.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1VX7vc-0007cj-To for linux-arm-kernel@lists.infradead.org; Fri, 18 Oct 2013 11:09:13 +0000 Received: by mail-pd0-f176.google.com with SMTP id g10so3558232pdj.35 for ; Fri, 18 Oct 2013 04:08:52 -0700 (PDT) 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=dZv5uD+m1V+ZgfiKgROoT5XQQ5bsEfajGhVg505EcHw=; b=aDVcz11qzjEfzpICOuLRP7Js9X/7i2Z9PZB/OTiumfjeqroLdz9mUFfckzKb1fsuqI 0XN0X9JHI1uHQILDPxWShvEKj2ghzMQCMwaVvpaAoRulVcjnULm86SK53Ayj7zYgw4vX dlN+KVQweinum8LXvkfn5GGHPv7pfVJrBbj4AFikscly6167z8a3eAufomnBA/6bY3QN 69oWa4seRNDdDmhRQcXmr+rRJAAzrr9eD+jjMRstRNCODVr7nnJMfchVQxM056KwBJIh VZROHgT2WcTPtg8kVoLzC6476Y/hy7YtR/VqW3UcqlegBl/KjY1XN0KUWPrcNopsxE0I vriA== X-Received: by 10.68.134.98 with SMTP id pj2mr2525882pbb.110.1382094529037; Fri, 18 Oct 2013 04:08:49 -0700 (PDT) Received: from ubuntu.caveonetworks.com ([115.119.134.194]) by mx.google.com with ESMTPSA id xs1sm3587419pac.7.2013.10.18.04.08.45 for (version=TLSv1.1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Fri, 18 Oct 2013 04:08:48 -0700 (PDT) From: vijay.kilari@gmail.com To: will.deacon@arm.com, sandeepa.prabhu@linaro.org, jason.wessel@windriver.com Subject: [PATCH v3 3/4] AArch64: KGDB: Add step debugging support Date: Fri, 18 Oct 2013 16:37:48 +0530 Message-Id: <1382094469-7971-4-git-send-email-vijay.kilari@gmail.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1382094469-7971-1-git-send-email-vijay.kilari@gmail.com> References: <1382094469-7971-1-git-send-email-vijay.kilari@gmail.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20131018_070913_076221_DF9C252C X-CRM114-Status: GOOD ( 17.15 ) X-Spam-Score: -2.0 (--) Cc: linaro-kernel@lists.linaro.org, linux@arm.linux.org.uk, Prasun.Kapoor@caviumnetworks.com, Vijaya Kumar K , takahiro.akashi@linaro.org, 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=-4.5 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=unavailable 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. If no step address is received from GDB tool, target assumes next step address is current PC. Software Step debugging is disabled when 'continue' command is received Signed-off-by: Vijaya Kumar K --- arch/arm64/kernel/kgdb.c | 58 +++++++++++++++++++++++++++++++++++++++------- 1 file changed, 50 insertions(+), 8 deletions(-) diff --git a/arch/arm64/kernel/kgdb.c b/arch/arm64/kernel/kgdb.c index 50cef79..2b0b987 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]) { @@ -158,14 +171,31 @@ int kgdb_arch_handle_exception(int exception_vector, int signo, * to the next instruction or 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); - 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); + /* + * Enable single step handling + */ + if (!kernel_active_single_step()) + kernel_enable_single_step(linux_regs); err = 0; break; default: @@ -188,6 +218,12 @@ 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), @@ -200,6 +236,10 @@ 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()); @@ -253,6 +293,7 @@ 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; } @@ -266,6 +307,7 @@ 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); }