From patchwork Mon Sep 30 09:44:11 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Vijay Kilari X-Patchwork-Id: 2963201 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 A75139F288 for ; Mon, 30 Sep 2013 09:47:06 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 5D5B020200 for ; Mon, 30 Sep 2013 09:47:05 +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 765FF20138 for ; Mon, 30 Sep 2013 09:47:00 +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 1VQa3N-00043c-AH; Mon, 30 Sep 2013 09:46:10 +0000 Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1VQa35-0006Ds-J3; Mon, 30 Sep 2013 09:45:51 +0000 Received: from mail-pd0-x22d.google.com ([2607:f8b0:400e:c02::22d]) by merlin.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1VQa2s-0006BH-CS for linux-arm-kernel@lists.infradead.org; Mon, 30 Sep 2013 09:45:39 +0000 Received: by mail-pd0-f173.google.com with SMTP id p10so5421452pdj.4 for ; Mon, 30 Sep 2013 02:45:16 -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=tOuwHS+s6H1ZJDR6NeEaY5DW2VOfaLQFHoHl9AlaBC8=; b=H5XGMDX5UZLumCM399Dlc1bdl1tFcgeKriztw4oUub0Lf1SQ6pgGcpoi4PbRW67l49 PO1ioR5S/Ki6Myq4YfmchPPP9hITzuw0RTjBf4VSAmR2aj/x1RNNdC8tzLxBp1XTK0nJ WZnt8Hn1mC/SbUOHT4mAp7NRqozWiq2iqfBN016cm6o16w33r6eQPlEwYJ+ynXWPZ6kW iSDIDcrmPJkqQu4Xk1Nzx+UEIc7ebP+iw4sqdiXcB+RqL2CHlgt6vircTWVq34v0VH69 G0PfsTHmpnPZDRJj0L+HDmFZSwDPdnGDE6cBPGm54D8tlMBtGqwK5ohW6xPQG3ms3W16 qcgg== X-Received: by 10.68.171.66 with SMTP id as2mr23007427pbc.94.1380534316634; Mon, 30 Sep 2013 02:45:16 -0700 (PDT) Received: from ubuntu.caveonetworks.com ([115.119.134.194]) by mx.google.com with ESMTPSA id xe9sm32013639pab.0.1969.12.31.16.00.00 (version=TLSv1.1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Mon, 30 Sep 2013 02:45:16 -0700 (PDT) From: vijay.kilari@gmail.com To: will.deacon@arm.com, sandeepa.prabhu@linaro.org, jason.wessel@windriver.com Subject: [PATCH v2 3/3] AArch64: KGDB: Add step debugging support Date: Mon, 30 Sep 2013 15:14:11 +0530 Message-Id: <1380534251-4464-4-git-send-email-vijay.kilari@gmail.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1380534251-4464-1-git-send-email-vijay.kilari@gmail.com> References: <1380534251-4464-1-git-send-email-vijay.kilari@gmail.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20130930_054538_524873_F4199AFA X-CRM114-Status: GOOD ( 17.61 ) 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=-4.7 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. 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 | 59 +++++++++++++++++++++++++++++++++++++++------- 1 file changed, 51 insertions(+), 8 deletions(-) diff --git a/arch/arm64/kernel/kgdb.c b/arch/arm64/kernel/kgdb.c index c99e04d..2d2485f 100644 --- a/arch/arm64/kernel/kgdb.c +++ b/arch/arm64/kernel/kgdb.c @@ -152,13 +152,26 @@ 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]) { @@ -173,14 +186,31 @@ 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: @@ -205,6 +235,13 @@ 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, + unsigned long addr) +{ + kgdb_handle_exception(1, SIGTRAP, 0, regs); + return 0; +} + static struct break_hook kgdb_brkpt_hook = { .esr_mask = 0xffffffff, .esr_val = KGDB_BREAKINST_ESR_VAL, @@ -217,6 +254,10 @@ 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()); @@ -272,6 +313,7 @@ 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; } @@ -286,6 +328,7 @@ 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); }