From patchwork Tue Nov 18 20:19:17 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Liviu Ionescu X-Patchwork-Id: 412154 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from lists.gnu.org (lists.gnu.org [IPv6:2001:4830:134:3::11]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id BE98214012B for ; Wed, 19 Nov 2014 07:20:11 +1100 (AEDT) Received: from localhost ([::1]:55178 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XqpFw-00051W-CX for incoming@patchwork.ozlabs.org; Tue, 18 Nov 2014 15:20:08 -0500 Received: from eggs.gnu.org ([2001:4830:134:3::10]:52081) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XqpFW-0004Yu-9i for qemu-devel@nongnu.org; Tue, 18 Nov 2014 15:19:47 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1XqpFN-0008A9-RS for qemu-devel@nongnu.org; Tue, 18 Nov 2014 15:19:42 -0500 Received: from [109.99.239.84] (port=36041 helo=ilg-mbp.local) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XqpFN-00089x-Gj for qemu-devel@nongnu.org; Tue, 18 Nov 2014 15:19:33 -0500 Received: by ilg-mbp.local (Postfix, from userid 501) id C15A52E07089; Tue, 18 Nov 2014 22:19:27 +0200 (EET) From: Liviu Ionescu To: qemu-devel@nongnu.org Date: Tue, 18 Nov 2014 22:19:17 +0200 Message-Id: <1416341957-9796-1-git-send-email-ilg@livius.net> X-Mailer: git-send-email 1.9.3 (Apple Git-50) X-detected-operating-system: by eggs.gnu.org: iOS iPhone or iPad X-Received-From: 109.99.239.84 Cc: peter.maydell@linaro.org, ilg@livius.net Subject: [Qemu-devel] [PATCH v2] Add the "-semihosting-config" option. X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org The usual semihosting behaviour is to process the system calls locally and return; unfortuantelly the initial implementation dinamically changed the target to GDB during debug sessions, which, for the usual arm-none-eabi-gdb, is not implemented. The result was that during debug sessions the semihosting calls were discarded. This patch adds a configuration variable and an option to set it on the command line: -semihosting-config [enable=on|off,]target=native|gdb|auto This option enables semihosting and defines where the semihosting calls will be addressed, to QEMU ('native') or to GDB ('gdb'). The default is auto, which means 'gdb' during debug sessions and 'native' otherwise. Signed-off-by: Liviu Ionescu --- gdbstub.c | 13 +++++++++++-- include/sysemu/sysemu.h | 6 ++++++ qemu-options.hx | 12 +++++++++++- vl.c | 49 +++++++++++++++++++++++++++++++++++++++++++++++++ 4 files changed, 77 insertions(+), 3 deletions(-) diff --git a/gdbstub.c b/gdbstub.c index 0faca56..982f039 100644 --- a/gdbstub.c +++ b/gdbstub.c @@ -351,10 +351,19 @@ static enum { GDB_SYS_DISABLED, } gdb_syscall_mode; -/* If gdb is connected when the first semihosting syscall occurs then use - remote gdb syscalls. Otherwise use native file IO. */ +/* Decide if either remote gdb syscalls or native file IO should be used. */ int use_gdb_syscalls(void) { + if (semihosting_target == SEMIHOSTING_TARGET_NATIVE) { + /* -semihosting-config target=native */ + return false; + } else if (semihosting_target == SEMIHOSTING_TARGET_GDB) { + /* -semihosting-config target=gdb */ + return true; + } + + /* -semihosting-config target=auto */ + /* On the first call check if gdb is connected and remember. */ if (gdb_syscall_mode == GDB_SYS_UNKNOWN) { gdb_syscall_mode = (gdbserver_state ? GDB_SYS_ENABLED : GDB_SYS_DISABLED); diff --git a/include/sysemu/sysemu.h b/include/sysemu/sysemu.h index 9fea3bc..c145d94 100644 --- a/include/sysemu/sysemu.h +++ b/include/sysemu/sysemu.h @@ -127,7 +127,13 @@ extern int cursor_hide; extern int graphic_rotate; extern int no_quit; extern int no_shutdown; + extern int semihosting_enabled; +extern int semihosting_target; +#define SEMIHOSTING_TARGET_AUTO 0 +#define SEMIHOSTING_TARGET_NATIVE 1 +#define SEMIHOSTING_TARGET_GDB 2 + extern int old_param; extern int boot_menu; extern bool boot_strict; diff --git a/qemu-options.hx b/qemu-options.hx index da9851d..3e81222 100644 --- a/qemu-options.hx +++ b/qemu-options.hx @@ -3216,7 +3216,17 @@ DEF("semihosting", 0, QEMU_OPTION_semihosting, STEXI @item -semihosting @findex -semihosting -Semihosting mode (ARM, M68K, Xtensa only). +Enable semihosting mode (ARM, M68K, Xtensa only). +ETEXI +DEF("semihosting-config", HAS_ARG, QEMU_OPTION_semihosting_config, + "-semihosting-config [enable=on|off,]target=native|gdb|auto semihosting configuration\n", +QEMU_ARCH_ARM | QEMU_ARCH_M68K | QEMU_ARCH_XTENSA | QEMU_ARCH_LM32) +STEXI +@item -semihosting-config [enable=on|off,]target=native|gdb|auto +@findex -semihosting-config +Enable semihosting and define where the semihosting calls will be addressed, +to QEMU (@code{native}) or to GDB (@code{gdb}). The default is @code{auto}, which means +@code{gdb} during debug sessions and @code{native} otherwise (ARM, M68K, Xtensa only). ETEXI DEF("old-param", 0, QEMU_OPTION_old_param, "-old-param old param mode\n", QEMU_ARCH_ARM) diff --git a/vl.c b/vl.c index f4a6e5e..8844983 100644 --- a/vl.c +++ b/vl.c @@ -172,6 +172,7 @@ const char *watchdog; QEMUOptionRom option_rom[MAX_OPTION_ROMS]; int nb_option_roms; int semihosting_enabled = 0; +int semihosting_target = SEMIHOSTING_TARGET_AUTO; int old_param = 0; const char *qemu_name; int alt_grab = 0; @@ -554,6 +555,22 @@ static QemuOptsList qemu_icount_opts = { }, }; +static QemuOptsList qemu_semihosting_config_opts = { + .name = "semihosting-config", + .implied_opt_name = "enable", + .head = QTAILQ_HEAD_INITIALIZER(qemu_semihosting_config_opts.head), + .desc = { + { + .name = "enable", + .type = QEMU_OPT_BOOL, + }, { + .name = "target", + .type = QEMU_OPT_STRING, + }, + { /* end of list */ } + }, +}; + /** * Get machine options * @@ -2811,6 +2828,7 @@ int main(int argc, char **argv, char **envp) qemu_add_opts(&qemu_name_opts); qemu_add_opts(&qemu_numa_opts); qemu_add_opts(&qemu_icount_opts); + qemu_add_opts(&qemu_semihosting_config_opts); runstate_init(); @@ -3618,6 +3636,37 @@ int main(int argc, char **argv, char **envp) break; case QEMU_OPTION_semihosting: semihosting_enabled = 1; + semihosting_target = SEMIHOSTING_TARGET_AUTO; + break; + case QEMU_OPTION_semihosting_config: + semihosting_enabled = 1; + opts = qemu_opts_parse(qemu_find_opts("semihosting-config"), + optarg, 0); + if (opts != NULL) { + semihosting_enabled = qemu_opt_get_bool(opts, "enable", + true); + const char *target = qemu_opt_get(opts, "target"); + if (target != NULL) { + if (strcmp("native", target) == 0) { + semihosting_target = SEMIHOSTING_TARGET_NATIVE; + } else if (strcmp("gdb", target) == 0) { + semihosting_target = SEMIHOSTING_TARGET_GDB; + } else if (strcmp("auto", target) == 0) { + semihosting_target = SEMIHOSTING_TARGET_AUTO; + } else { + fprintf(stderr, "Unsupported semihosting-config" + " %s\n", + optarg); + exit(1); + } + } else { + semihosting_target = SEMIHOSTING_TARGET_AUTO; + } + } else { + fprintf(stderr, "Unsupported semihosting-config %s\n", + optarg); + exit(1); + } break; case QEMU_OPTION_tdf: fprintf(stderr, "Warning: user space PIT time drift fix "