From patchwork Tue Jan 28 11:20:19 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Vijay Kilari X-Patchwork-Id: 3546311 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 90F13C02DC for ; Tue, 28 Jan 2014 11:25:22 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 5D06320109 for ; Tue, 28 Jan 2014 11:25:21 +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 F2A9B200C1 for ; Tue, 28 Jan 2014 11:25:19 +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 1W86m3-0002Kz-QZ; Tue, 28 Jan 2014 11:24:12 +0000 Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1W86lm-0002cL-T3; Tue, 28 Jan 2014 11:23:54 +0000 Received: from mail-pb0-x22c.google.com ([2607:f8b0:400e:c01::22c]) by merlin.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1W86lI-0002Vc-DU for linux-arm-kernel@lists.infradead.org; Tue, 28 Jan 2014 11:23:26 +0000 Received: by mail-pb0-f44.google.com with SMTP id rq2so244806pbb.17 for ; Tue, 28 Jan 2014 03:23:02 -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=URXdazszDEDRtgatYKv3SSRbh26W5SEvicvnV3Nd5TEubcpl996mZMukY0ja4QT+Kj hRx9TCegnnwULnkT2VPweIXUaGA59+Xqwn16UdXoZOsbC1uwXmt+G6pvRyKRbSx3lToW 3eyxjEfIWqTAjTlrocDlE6ookpLjdoOPPQKZf3oiv+6CP+8XI5q2i+3o8mHPKuRkWH9d O7hc9AAux6GHL68ipuEBP4hDoEV6qeaWEOBE80nBHXiJKal09aGWohbIwCUsSMzaRICQ 9hv2DNTTfamNUIPYohHcOYDPDLkKwkkTxWctC2gYlnhoiTABHMLm0X4qxnyp4Ya1ujIF T5Gw== X-Received: by 10.68.133.6 with SMTP id oy6mr817872pbb.153.1390908182716; Tue, 28 Jan 2014 03:23:02 -0800 (PST) Received: from ubuntu.caveonetworks.com ([115.119.134.194]) by mx.google.com with ESMTPSA id bz4sm41563650pbb.12.2014.01.28.03.22.59 for (version=TLSv1.1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Tue, 28 Jan 2014 03:23:02 -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 v9 3/6] arm64: KGDB: Add step debugging support Date: Tue, 28 Jan 2014 16:50:19 +0530 Message-Id: <1390908022-10287-4-git-send-email-vijay.kilari@gmail.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1390908022-10287-1-git-send-email-vijay.kilari@gmail.com> References: <1390908022-10287-1-git-send-email-vijay.kilari@gmail.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20140128_062324_627062_6F0186B0 X-CRM114-Status: GOOD ( 16.79 ) 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=-4.6 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); }