From 32f51db640131e8c3cc089c7a03271111b6cb070 Mon Sep 17 00:00:00 2001 From: Markus Armbruster Date: Thu, 19 Jan 2012 18:58:30 +0100 Subject: [PATCH 3/4] debugcon: support for debugging consoles (e.g. Bochs port 0xe9) RH-Author: Markus Armbruster Message-id: <1326999511-23666-2-git-send-email-armbru@redhat.com> Patchwork-id: 36650 O-Subject: [RHEL-6.3 PATCH qemu-kvm 1/2] debugcon: support for debugging consoles (e.g. Bochs port 0xe9) Bugzilla: 782825 RH-Acked-by: Gerd Hoffmann RH-Acked-by: Kevin Wolf RH-Acked-by: Paolo Bonzini RH-Acked-by: Gleb Natapov From: "H. Peter Anvin" Add generic support for debugging consoles (simple I/O ports which when written to cause debugging output to be written to a target.) The current implementation matches Bochs' port 0xe9, allowing the same debugging code to be used for both Bochs and Qemu. There is no vm state associated with the debugging port, simply because it has none -- the entire interface is a single, stateless, write-only port. Most of the code was cribbed from the serial port driver. v2: removed non-ISA variants (they can be introduced when/if someone wants them, using code from the serial port); added configurable readback (Bochs returns 0xe9 on a read from this register, mimic that by default) This retains the apparently somewhat controversial user friendly option, however. v3: reimplemented the user friendly option as a synthetic option ("-debugcon foo" basically ends up being a parser-level shorthand for "-chardev stdio,id=debugcon -device isa-debugcon,chardev=debugcon") -- this dramatically reduced the complexity while keeping the same level of user friendliness. v4: spaces, not tabs. v5: update to match current top of tree. Calling qemu_chr_open() already during parsing no longer works; defer until we are parsing the other console-like devices. Signed-off-by: H. Peter Anvin Signed-off-by: Anthony Liguori (cherry picked from commit c9f398e53fedb88df243e32eb9bc50fda4ec44d0) Conflicts: Makefile.target vl.c debugcon.c adapted for our non-upstream commit 45b991f7. Note that -debugcon is entirely useless with SeaBios (wrong iobase). Use "-device isa-debugcon,iobase=0x402,chardev=...". Signed-off-by: Markus Armbruster --- Makefile.target | 1 + hw/debugcon.c | 110 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ qemu-options.hx | 11 +++++ vl.c | 23 +++++++++++ 4 files changed, 145 insertions(+), 0 deletions(-) create mode 100644 hw/debugcon.c Signed-off-by: Michal Novotny --- Makefile.target | 1 + hw/debugcon.c | 110 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ qemu-options.hx | 11 +++++ vl.c | 23 +++++++++++ 4 files changed, 145 insertions(+), 0 deletions(-) create mode 100644 hw/debugcon.c diff --git a/Makefile.target b/Makefile.target index 939334c..fc593f7 100644 --- a/Makefile.target +++ b/Makefile.target @@ -254,6 +254,7 @@ obj-i386-y += extboot.o obj-i386-y += ne2000-isa.o obj-i386-y += testdev.o obj-i386-y += kvmclock.o +obj-i386-y += debugcon.o obj-i386-$(CONFIG_KVM_PIT) += i8254-kvm.o obj-i386-$(CONFIG_KVM_DEVICE_ASSIGNMENT) += device-assignment.o diff --git a/hw/debugcon.c b/hw/debugcon.c new file mode 100644 index 0000000..631faa2 --- /dev/null +++ b/hw/debugcon.c @@ -0,0 +1,110 @@ +/* + * QEMU Bochs-style debug console ("port E9") emulation + * + * Copyright (c) 2003-2004 Fabrice Bellard + * Copyright (c) 2008 Citrix Systems, Inc. + * Copyright (c) Intel Corporation; author: H. Peter Anvin + * + * Permission is hereby granted, free of charge, to any person obtaining a copy + * of this software and associated documentation files (the "Software"), to deal + * in the Software without restriction, including without limitation the rights + * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell + * copies of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in + * all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN + * THE SOFTWARE. + */ + +#include "hw.h" +#include "qemu-char.h" +#include "isa.h" +#include "pc.h" + +//#define DEBUG_DEBUGCON + +typedef struct DebugconState { + CharDriverState *chr; + uint32_t readback; +} DebugconState; + +typedef struct ISADebugconState { + ISADevice dev; + uint32_t iobase; + DebugconState state; +} ISADebugconState; + +static void debugcon_ioport_write(void *opaque, uint32_t addr, uint32_t val) +{ + DebugconState *s = opaque; + unsigned char ch = val; + +#ifdef DEBUG_DEBUGCON + printf("debugcon: write addr=0x%04x val=0x%02x\n", addr, val); +#endif + + qemu_chr_write(s->chr, &ch, 1); +} + + +static uint32_t debugcon_ioport_read(void *opaque, uint32_t addr) +{ + DebugconState *s = opaque; + +#ifdef DEBUG_DEBUGCON + printf("debugcon: read addr=0x%04x\n", addr, val); +#endif + + return s->readback; +} + +static const QemuChrHandlers chr_handlers = { +}; + +static void debugcon_init_core(DebugconState *s) +{ + if (!s->chr) { + fprintf(stderr, "Can't create debugcon device, empty char device\n"); + exit(1); + } + + qemu_chr_add_handlers(s->chr, &chr_handlers, s); +} + +static int debugcon_isa_initfn(ISADevice *dev) +{ + ISADebugconState *isa = DO_UPCAST(ISADebugconState, dev, dev); + DebugconState *s = &isa->state; + + debugcon_init_core(s); + register_ioport_write(isa->iobase, 1, 1, debugcon_ioport_write, s); + register_ioport_read(isa->iobase, 1, 1, debugcon_ioport_read, s); + return 0; +} + +static ISADeviceInfo debugcon_isa_info = { + .qdev.name = "isa-debugcon", + .qdev.size = sizeof(ISADebugconState), + .init = debugcon_isa_initfn, + .qdev.props = (Property[]) { + DEFINE_PROP_HEX32("iobase", ISADebugconState, iobase, 0xe9), + DEFINE_PROP_CHR("chardev", ISADebugconState, state.chr), + DEFINE_PROP_HEX32("readback", ISADebugconState, state.readback, 0xe9), + DEFINE_PROP_END_OF_LIST(), + }, +}; + +static void debugcon_register_devices(void) +{ + isa_qdev_register(&debugcon_isa_info); +} + +device_init(debugcon_register_devices) diff --git a/qemu-options.hx b/qemu-options.hx index 195b091..a014459 100644 --- a/qemu-options.hx +++ b/qemu-options.hx @@ -1731,6 +1731,17 @@ STEXI Setup monitor on chardev @var{name}. ETEXI +DEF("debugcon", HAS_ARG, QEMU_OPTION_debugcon, \ + "-debugcon dev redirect the debug console to char device 'dev'\n") +STEXI +@item -debugcon @var{dev} +Redirect the debug console to host device @var{dev} (same devices as the +serial port). The debug console is an I/O port which is typically port +0xe9; writing to that I/O port sends output to this device. +The default device is @code{vc} in graphical mode and @code{stdio} in +non graphical mode. +ETEXI + DEF("pidfile", HAS_ARG, QEMU_OPTION_pidfile, \ "-pidfile file write PID to 'file'\n") STEXI diff --git a/vl.c b/vl.c index 0e91a41..48ec0b3 100644 --- a/vl.c +++ b/vl.c @@ -4836,6 +4836,7 @@ struct device_config { DEV_SERIAL, /* -serial */ DEV_PARALLEL, /* -parallel */ DEV_VIRTCON, /* -virtioconsole */ + DEV_DEBUGCON, /* -debugcon */ } type; const char *cmdline; QTAILQ_ENTRY(device_config) next; @@ -4943,6 +4944,23 @@ static int virtcon_parse(const char *devname) return 0; } +static int debugcon_parse(const char *devname) +{ + QemuOpts *opts; + + if (!qemu_chr_open("debugcon", devname, NULL)) { + exit(1); + } + opts = qemu_opts_create(&qemu_device_opts, "debugcon", 1); + if (!opts) { + fprintf(stderr, "qemu: already have a debugcon device\n"); + exit(1); + } + qemu_opt_set(opts, "driver", "isa-debugcon"); + qemu_opt_set(opts, "chardev", "debugcon"); + return 0; +} + void qemu_add_machine_init_done_notifier(Notifier *notify) { notifier_list_add(&machine_init_done_notifiers, notify); @@ -5626,6 +5644,9 @@ int main(int argc, char **argv, char **envp) default_monitor = 0; } break; + case QEMU_OPTION_debugcon: + add_device_config(DEV_DEBUGCON, optarg); + break; case QEMU_OPTION_loadvm: loadvm = optarg; break; @@ -6235,6 +6256,8 @@ int main(int argc, char **argv, char **envp) exit(1); if (foreach_device_config(DEV_VIRTCON, virtcon_parse) < 0) exit(1); + if (foreach_device_config(DEV_DEBUGCON, debugcon_parse) < 0) + exit(1); module_call_init(MODULE_INIT_DEVICE); -- 1.7.7.5