From patchwork Wed Jan 22 14:42:50 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Vijay Kilari X-Patchwork-Id: 3523671 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 6C33E9F2E9 for ; Wed, 22 Jan 2014 14:47:59 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 3D6EB2011D for ; Wed, 22 Jan 2014 14:47:58 +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 E119720117 for ; Wed, 22 Jan 2014 14:47:56 +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 1W5z5D-0007nG-E2; Wed, 22 Jan 2014 14:47:12 +0000 Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1W5z4y-0000Nb-ME; Wed, 22 Jan 2014 14:46:56 +0000 Received: from mail-pd0-x22b.google.com ([2607:f8b0:400e:c02::22b]) by merlin.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1W5z4g-0000Js-O6 for linux-arm-kernel@lists.infradead.org; Wed, 22 Jan 2014 14:46:41 +0000 Received: by mail-pd0-f171.google.com with SMTP id g10so453211pdj.2 for ; Wed, 22 Jan 2014 06:46:17 -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=I/w7NOaDa1RPIRhl/2irBDKrQE3riGviD00xtJONELkdxlw5X1Ri2KyZ9oRmX5vju/ OLw+77HQp/LCcvhbYX6KSvRTmpQ80H8vHDxXtKG3UpyAGqH5qC7FG/e/Tj3bl3f01Dje C88ZrPCz8gl9+uiC+iZxFbgo/Ws3QCjjxlQeEcd62I6l72bdnIuchIH0iy5ncbSN4+i7 WWeoVliwv9ZMsBccUoYxFo0ZbhW+PNCLxXtDAgj10A2TV0ddA1LYYjX17yPZGhmzuOtT Mk0jFRQbPc30UUMs7OzIihJVknvwXhYpsC2E3veOi6Oye959xiFhFD+S8Jx4nKSoIfT9 ji2Q== X-Received: by 10.66.14.41 with SMTP id m9mr1953624pac.123.1390401977233; Wed, 22 Jan 2014 06:46:17 -0800 (PST) Received: from ubuntu.caveonetworks.com ([115.119.134.194]) by mx.google.com with ESMTPSA id db3sm23950684pbb.10.2014.01.22.06.46.13 for (version=TLSv1.1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Wed, 22 Jan 2014 06:46:16 -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 v7 3/6] arm64: KGDB: Add step debugging support Date: Wed, 22 Jan 2014 20:12:50 +0530 Message-Id: <1390401773-12100-4-git-send-email-vijay.kilari@gmail.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1390401773-12100-1-git-send-email-vijay.kilari@gmail.com> References: <1390401773-12100-1-git-send-email-vijay.kilari@gmail.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20140122_094638_937523_691CC34C X-CRM114-Status: GOOD ( 16.81 ) 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=-4.7 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); }