From patchwork Thu Oct 24 22:46:22 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Keith Packard X-Patchwork-Id: 11210997 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 2EED4112B for ; Thu, 24 Oct 2019 22:47:15 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 0D2F52084C for ; Thu, 24 Oct 2019 22:47:14 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 0D2F52084C Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=keithp.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Received: from localhost ([::1]:52228 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iNlsw-0000Q3-0T for patchwork-qemu-devel@patchwork.kernel.org; Thu, 24 Oct 2019 18:47:14 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:48791) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iNlsL-0008IT-V4 for qemu-devel@nongnu.org; Thu, 24 Oct 2019 18:46:39 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1iNlsK-000647-7d for qemu-devel@nongnu.org; Thu, 24 Oct 2019 18:46:37 -0400 Received: from home.keithp.com ([63.227.221.253]:36582 helo=elaine.keithp.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1iNlsJ-00062g-VZ for qemu-devel@nongnu.org; Thu, 24 Oct 2019 18:46:36 -0400 Received: from localhost (localhost [127.0.0.1]) by elaine.keithp.com (Postfix) with ESMTP id 95DF93F22AA4 for ; Thu, 24 Oct 2019 15:46:31 -0700 (PDT) X-Virus-Scanned: Debian amavisd-new at keithp.com Received: from elaine.keithp.com ([127.0.0.1]) by localhost (elaine.keithp.com [127.0.0.1]) (amavisd-new, port 10024) with LMTP id gPS-UOSQ_QDJ; Thu, 24 Oct 2019 15:46:31 -0700 (PDT) Received: from keithp.com (unknown [172.58.45.131]) by elaine.keithp.com (Postfix) with ESMTPSA id CCC4B3F22A62; Thu, 24 Oct 2019 15:46:30 -0700 (PDT) Received: by keithp.com (Postfix, from userid 1000) id 29D23158212D; Thu, 24 Oct 2019 15:46:29 -0700 (PDT) From: Keith Packard To: qemu-devel@nongnu.org Subject: [PATCH] Semihost SYS_READC implementation (v4) Date: Thu, 24 Oct 2019 15:46:22 -0700 Message-Id: <20191024224622.12371-1-keithp@keithp.com> X-Mailer: git-send-email 2.24.0.rc0 In-Reply-To: <89ada4b1-ee3d-a512-07c2-9bc1ba5806da@redhat.com> References: <89ada4b1-ee3d-a512-07c2-9bc1ba5806da@redhat.com> MIME-Version: 1.0 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 63.227.221.253 X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Keith Packard Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" Provides a blocking call to read a character from the console using semihosting.chardev, if specified. This takes some careful command line options to use stdio successfully as the serial ports, monitor and semihost all want to use stdio. Here's a sample set of command line options which share stdio betwen semihost, monitor and serial ports: qemu \ -chardev stdio,mux=on,id=stdio0 \ -serial chardev:stdio0 \ -semihosting-config enable=on,chardev=stdio0 \ -mon chardev=stdio0,mode=readline This creates a chardev hooked to stdio and then connects all of the subsystems to it. A shorter mechanism would be good to hear about. v2: Add implementation in linux-user/arm/semihost.c v3: (thanks to Paolo Bonzini ) Replace hand-rolled fifo with fifo8 Avoid mixing code and declarations Remove spurious (void) cast of function parameters Define qemu_semihosting_console_init when CONFIG_USER_ONLY v4: Add qemu_semihosting_console_init to stubs/semihost.c for hosts that don't support semihosting Signed-off-by: Keith Packard --- hw/semihosting/console.c | 73 +++++++++++++++++++++++++++++++ include/hw/semihosting/console.h | 12 +++++ include/hw/semihosting/semihost.h | 4 ++ linux-user/arm/semihost.c | 24 ++++++++++ target/arm/arm-semi.c | 3 +- vl.c | 3 ++ 6 files changed, 117 insertions(+), 2 deletions(-) diff --git a/hw/semihosting/console.c b/hw/semihosting/console.c index b4b17c8afb..197bff079b 100644 --- a/hw/semihosting/console.c +++ b/hw/semihosting/console.c @@ -98,3 +98,76 @@ void qemu_semihosting_console_outc(CPUArchState *env, target_ulong addr) __func__, addr); } } + +#include +#include "chardev/char-fe.h" +#include "sysemu/sysemu.h" +#include "qemu/main-loop.h" +#include "qapi/error.h" +#include "qemu/fifo8.h" + +#define FIFO_SIZE 1024 + +typedef struct SemihostingConsole { + CharBackend backend; + pthread_mutex_t mutex; + pthread_cond_t cond; + bool got; + Fifo8 fifo; +} SemihostingConsole; + +static SemihostingConsole console = { + .mutex = PTHREAD_MUTEX_INITIALIZER, + .cond = PTHREAD_COND_INITIALIZER +}; + +static int console_can_read(void *opaque) +{ + SemihostingConsole *c = opaque; + int ret; + pthread_mutex_lock(&c->mutex); + ret = (int) fifo8_num_free(&c->fifo); + pthread_mutex_unlock(&c->mutex); + return ret; +} + +static void console_read(void *opaque, const uint8_t *buf, int size) +{ + SemihostingConsole *c = opaque; + pthread_mutex_lock(&c->mutex); + while (size-- && !fifo8_is_full(&c->fifo)) { + fifo8_push(&c->fifo, *buf++); + } + pthread_cond_broadcast(&c->cond); + pthread_mutex_unlock(&c->mutex); +} + +target_ulong qemu_semihosting_console_inc(CPUArchState *env) +{ + uint8_t ch; + SemihostingConsole *c = &console; + qemu_mutex_unlock_iothread(); + pthread_mutex_lock(&c->mutex); + while (fifo8_is_empty(&c->fifo)) { + pthread_cond_wait(&c->cond, &c->mutex); + } + ch = fifo8_pop(&c->fifo); + pthread_mutex_unlock(&c->mutex); + qemu_mutex_lock_iothread(); + return (target_ulong) ch; +} + +void qemu_semihosting_console_init(void) +{ + Chardev *chr = semihosting_get_chardev(); + + if (chr) { + fifo8_create(&console.fifo, FIFO_SIZE); + qemu_chr_fe_init(&console.backend, chr, &error_abort); + qemu_chr_fe_set_handlers(&console.backend, + console_can_read, + console_read, + NULL, NULL, &console, + NULL, true); + } +} diff --git a/include/hw/semihosting/console.h b/include/hw/semihosting/console.h index 9be9754bcd..f7d5905b41 100644 --- a/include/hw/semihosting/console.h +++ b/include/hw/semihosting/console.h @@ -37,6 +37,18 @@ int qemu_semihosting_console_outs(CPUArchState *env, target_ulong s); */ void qemu_semihosting_console_outc(CPUArchState *env, target_ulong c); +/** + * qemu_semihosting_console_inc: + * @env: CPUArchState + * + * Receive single character from debug console. This + * may be the remote gdb session if a softmmu guest is currently being + * debugged. + * + * Returns: character read or -1 on error + */ +target_ulong qemu_semihosting_console_inc(CPUArchState *env); + /** * qemu_semihosting_log_out: * @s: pointer to string diff --git a/include/hw/semihosting/semihost.h b/include/hw/semihosting/semihost.h index 60fc42d851..b8ce5117ae 100644 --- a/include/hw/semihosting/semihost.h +++ b/include/hw/semihosting/semihost.h @@ -56,6 +56,9 @@ static inline Chardev *semihosting_get_chardev(void) { return NULL; } +static inline void qemu_semihosting_console_init(void) +{ +} #else /* !CONFIG_USER_ONLY */ bool semihosting_enabled(void); SemihostingTarget semihosting_get_target(void); @@ -68,6 +71,7 @@ Chardev *semihosting_get_chardev(void); void qemu_semihosting_enable(void); int qemu_semihosting_config_options(const char *opt); void qemu_semihosting_connect_chardevs(void); +void qemu_semihosting_console_init(void); #endif /* CONFIG_USER_ONLY */ #endif /* SEMIHOST_H */ diff --git a/linux-user/arm/semihost.c b/linux-user/arm/semihost.c index a16b525eec..13a097515b 100644 --- a/linux-user/arm/semihost.c +++ b/linux-user/arm/semihost.c @@ -47,3 +47,27 @@ void qemu_semihosting_console_outc(CPUArchState *env, target_ulong addr) } } } + +#include + +target_ulong qemu_semihosting_console_inc(CPUArchState *env) +{ + uint8_t c; + struct pollfd pollfd = { + .fd = STDIN_FILENO, + .events = POLLIN + }; + + if (poll(&pollfd, 1, -1) != 1) { + qemu_log_mask(LOG_UNIMP, "%s: unexpected read from stdin failure", + __func__); + return (target_ulong) -1; + } + + if (read(STDIN_FILENO, &c, 1) != 1) { + qemu_log_mask(LOG_UNIMP, "%s: unexpected read from stdin failure", + __func__); + return (target_ulong) -1; + } + return (target_ulong) c; +} diff --git a/target/arm/arm-semi.c b/target/arm/arm-semi.c index 6f7b6d801b..47d61f6fe1 100644 --- a/target/arm/arm-semi.c +++ b/target/arm/arm-semi.c @@ -802,8 +802,7 @@ target_ulong do_arm_semihosting(CPUARMState *env) return guestfd_fns[gf->type].readfn(cpu, gf, arg1, len); case TARGET_SYS_READC: - qemu_log_mask(LOG_UNIMP, "%s: SYS_READC not implemented", __func__); - return 0; + return qemu_semihosting_console_inc(env); case TARGET_SYS_ISTTY: GET_ARG(0); diff --git a/vl.c b/vl.c index 4489cfb2bb..ac584d97ea 100644 --- a/vl.c +++ b/vl.c @@ -4381,6 +4381,9 @@ int main(int argc, char **argv, char **envp) ds = init_displaystate(); qemu_display_init(ds, &dpy); + /* connect semihosting console input if requested */ + qemu_semihosting_console_init(); + /* must be after terminal init, SDL library changes signal handlers */ os_setup_signal_handling();