From patchwork Wed Feb 19 04:35:38 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Vijay Kilari X-Patchwork-Id: 3677821 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 4A20CBF13A for ; Wed, 19 Feb 2014 04:40:34 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 6034B20163 for ; Wed, 19 Feb 2014 04:40:33 +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 410122015E for ; Wed, 19 Feb 2014 04:40:32 +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 1WFywp-00084I-1p; Wed, 19 Feb 2014 04:39:51 +0000 Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1WFywe-0002g8-4g; Wed, 19 Feb 2014 04:39:40 +0000 Received: from mail-pb0-f46.google.com ([209.85.160.46]) by merlin.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1WFywT-0002dQ-GQ for linux-arm-kernel@lists.infradead.org; Wed, 19 Feb 2014 04:39:31 +0000 Received: by mail-pb0-f46.google.com with SMTP id um1so17588774pbc.5 for ; Tue, 18 Feb 2014 20:39:05 -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=BKgSByrkdOimWLdHJ5kELZD3VMfc2dILt3a4x6bHlBg=; b=vcsx72ZSirYmCIJVHFSEKHOaiwZbcMyEaYXVGEkD8s6T6J40vYgfDF4E0kxDbFDofg rABpqvNFnEa5uzj/DEPIJHfLc8Jn40thAer3Tld6whb41sGx3edXyWYGFHqcuzCG5MR+ Gkn5ekqTKnhv3EPJqslm1HNEJWCxO9wmOrbu9kjw69COakz5z7mOe5jBhyYkPK5jfMPI WCt85SR4ZvauVJT1cDDVTM67I4ZyR+FELE1Dcuf25afxD67ieQwvHyHZdLpjC7j7mZqC RqMVFl25EXQZ8A791qZQJUOr+leXgzCN/uWYvv4BoNdCInAHy70qqrZW8Jbmifp0+XCD WQ+g== X-Received: by 10.69.31.97 with SMTP id kl1mr37745766pbd.62.1392784745091; Tue, 18 Feb 2014 20:39:05 -0800 (PST) Received: from ubuntu.caveonetworks.com ([115.119.134.194]) by mx.google.com with ESMTPSA id bz4sm61475618pbb.12.2014.02.18.20.39.01 for (version=TLSv1.1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Tue, 18 Feb 2014 20:39:04 -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 v10 3/6] arm64: KGDB: Add step debugging support Date: Wed, 19 Feb 2014 10:05:38 +0530 Message-Id: <1392784541-18034-4-git-send-email-vijay.kilari@gmail.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1392784541-18034-1-git-send-email-vijay.kilari@gmail.com> References: <1392784541-18034-1-git-send-email-vijay.kilari@gmail.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20140218_233929_713410_4E2959F2 X-CRM114-Status: GOOD ( 16.70 ) X-Spam-Score: -2.7 (--) 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=-4.6 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 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 | 64 ++++++++++++++++++++++++++++++++++++++++------ 1 file changed, 56 insertions(+), 8 deletions(-) diff --git a/arch/arm64/kernel/kgdb.c b/arch/arm64/kernel/kgdb.c index 4b7a569..75c9cf1 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]) { @@ -162,13 +175,36 @@ 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; + + /* + * 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; - compiled_break = 0; + /* + * Enable single step handling + */ + if (!kernel_active_single_step()) + kernel_enable_single_step(linux_regs); err = 0; break; default: @@ -191,6 +227,12 @@ 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), @@ -203,6 +245,10 @@ 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()); @@ -259,6 +305,7 @@ 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; } @@ -271,6 +318,7 @@ 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); }