From: minyard@acm.org
To: qemu-devel@nongnu.org
Cc: Corey Minyard <cminyard@mvista.com>
Subject: [Qemu-devel] [PATCH v3 03/16] ipmi: Add an external connection simulation interface
Date: Mon, 8 Jun 2015 20:11:58 -0500 [thread overview]
Message-ID: <1433812331-18993-4-git-send-email-minyard@acm.org> (raw)
In-Reply-To: <1433812331-18993-1-git-send-email-minyard@acm.org>
From: Corey Minyard <cminyard@mvista.com>
This adds an interface for IPMI that connects to a remote
BMC over a chardev (generally a TCP socket). The OpenIPMI
lanserv simulator describes this interface, see that for
interface details.
Signed-off-by: Corey Minyard <cminyard@mvista.com>
---
default-configs/i386-softmmu.mak | 1 +
default-configs/x86_64-softmmu.mak | 1 +
hw/ipmi/Makefile.objs | 1 +
hw/ipmi/ipmi_bmc_extern.c | 478 +++++++++++++++++++++++++++++++++++++
4 files changed, 481 insertions(+)
create mode 100644 hw/ipmi/ipmi_bmc_extern.c
diff --git a/default-configs/i386-softmmu.mak b/default-configs/i386-softmmu.mak
index 25fce7d..62d9c1e 100644
--- a/default-configs/i386-softmmu.mak
+++ b/default-configs/i386-softmmu.mak
@@ -10,6 +10,7 @@ CONFIG_VMWARE_VGA=y
CONFIG_VMMOUSE=y
CONFIG_IPMI=y
CONFIG_IPMI_LOCAL=y
+CONFIG_IPMI_EXTERN=y
CONFIG_SERIAL=y
CONFIG_PARALLEL=y
CONFIG_I8254=y
diff --git a/default-configs/x86_64-softmmu.mak b/default-configs/x86_64-softmmu.mak
index 2179574..0f12f45 100644
--- a/default-configs/x86_64-softmmu.mak
+++ b/default-configs/x86_64-softmmu.mak
@@ -10,6 +10,7 @@ CONFIG_VMWARE_VGA=y
CONFIG_VMMOUSE=y
CONFIG_IPMI=y
CONFIG_IPMI_LOCAL=y
+CONFIG_IPMI_EXTERN=y
CONFIG_SERIAL=y
CONFIG_PARALLEL=y
CONFIG_I8254=y
diff --git a/hw/ipmi/Makefile.objs b/hw/ipmi/Makefile.objs
index 875271c..ddb15ec 100644
--- a/hw/ipmi/Makefile.objs
+++ b/hw/ipmi/Makefile.objs
@@ -1,2 +1,3 @@
common-obj-$(CONFIG_IPMI) += ipmi.o
common-obj-$(CONFIG_IPMI_LOCAL) += ipmi_bmc_sim.o
+common-obj-$(CONFIG_IPMI_LOCAL) += ipmi_bmc_extern.o
diff --git a/hw/ipmi/ipmi_bmc_extern.c b/hw/ipmi/ipmi_bmc_extern.c
new file mode 100644
index 0000000..d4669f0
--- /dev/null
+++ b/hw/ipmi/ipmi_bmc_extern.c
@@ -0,0 +1,478 @@
+/*
+ * IPMI BMC external connection
+ *
+ * Copyright (c) 2015 Corey Minyard, MontaVista Software, LLC
+ *
+ * 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.
+ */
+
+/*
+ * This is designed to connect with OpenIPMI's lanserv serial interface
+ * using the "VM" connection type. See that for details.
+ */
+
+#include <stdint.h>
+#include "qemu/timer.h"
+#include "sysemu/char.h"
+#include "hw/ipmi/ipmi.h"
+
+#define VM_MSG_CHAR 0xA0 /* Marks end of message */
+#define VM_CMD_CHAR 0xA1 /* Marks end of a command */
+#define VM_ESCAPE_CHAR 0xAA /* Set bit 4 from the next byte to 0 */
+
+#define VM_PROTOCOL_VERSION 1
+#define VM_CMD_VERSION 0xff /* A version number byte follows */
+#define VM_CMD_NOATTN 0x00
+#define VM_CMD_ATTN 0x01
+#define VM_CMD_ATTN_IRQ 0x02
+#define VM_CMD_POWEROFF 0x03
+#define VM_CMD_RESET 0x04
+#define VM_CMD_ENABLE_IRQ 0x05 /* Enable/disable the messaging irq */
+#define VM_CMD_DISABLE_IRQ 0x06
+#define VM_CMD_SEND_NMI 0x07
+#define VM_CMD_CAPABILITIES 0x08
+#define VM_CAPABILITIES_POWER 0x01
+#define VM_CAPABILITIES_RESET 0x02
+#define VM_CAPABILITIES_IRQ 0x04
+#define VM_CAPABILITIES_NMI 0x08
+#define VM_CAPABILITIES_ATTN 0x10
+
+#define TYPE_IPMI_BMC_EXTERN "ipmi-bmc-extern"
+#define IPMI_BMC_EXTERN(obj) OBJECT_CHECK(IPMIBmcExtern, (obj), \
+ TYPE_IPMI_BMC_EXTERN)
+typedef struct IPMIBmcExtern {
+ IPMIBmc parent;
+
+ CharDriverState *chr;
+
+ bool connected;
+
+ unsigned char inbuf[MAX_IPMI_MSG_SIZE + 2];
+ unsigned int inpos;
+ bool in_escape;
+ bool in_too_many;
+ bool waiting_rsp;
+ bool sending_cmd;
+
+ unsigned char outbuf[(MAX_IPMI_MSG_SIZE + 2) * 2 + 1];
+ unsigned int outpos;
+ unsigned int outlen;
+
+ struct QEMUTimer *extern_timer;
+
+ /* A reset event is pending to be sent upstream. */
+ bool send_reset;
+} IPMIBmcExtern;
+
+static int can_receive(void *opaque);
+static void receive(void *opaque, const uint8_t *buf, int size);
+static void chr_event(void *opaque, int event);
+
+static unsigned char
+ipmb_checksum(const unsigned char *data, int size, unsigned char start)
+{
+ unsigned char csum = start;
+
+ for (; size > 0; size--, data++) {
+ csum += *data;
+ }
+ return csum;
+}
+
+static void continue_send(IPMIBmcExtern *ibe)
+{
+ if (ibe->outlen == 0) {
+ goto check_reset;
+ }
+ send:
+ ibe->outpos += qemu_chr_fe_write(ibe->chr, ibe->outbuf + ibe->outpos,
+ ibe->outlen - ibe->outpos);
+ if (ibe->outpos < ibe->outlen) {
+ /* Not fully transmitted, try again in a 10ms */
+ timer_mod_ns(ibe->extern_timer,
+ qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + 10000000);
+ } else {
+ /* Sent */
+ ibe->outlen = 0;
+ ibe->outpos = 0;
+ if (!ibe->sending_cmd) {
+ ibe->waiting_rsp = true;
+ } else {
+ ibe->sending_cmd = false;
+ }
+ check_reset:
+ if (ibe->connected && ibe->send_reset) {
+ /* Send the reset */
+ ibe->outbuf[0] = VM_CMD_RESET;
+ ibe->outbuf[1] = VM_CMD_CHAR;
+ ibe->outlen = 2;
+ ibe->outpos = 0;
+ ibe->send_reset = false;
+ ibe->sending_cmd = true;
+ goto send;
+ }
+
+ if (ibe->waiting_rsp) {
+ /* Make sure we get a response within 4 seconds. */
+ timer_mod_ns(ibe->extern_timer,
+ qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + 4000000000ULL);
+ }
+ }
+ return;
+}
+
+static void extern_timeout(void *opaque)
+{
+ IPMIBmcExtern *ibe = opaque;
+ IPMIInterface *s = ibe->parent.intf;
+
+ if (ibe->connected) {
+ if (ibe->waiting_rsp && (ibe->outlen == 0)) {
+ IPMIInterfaceClass *k = IPMI_INTERFACE_GET_CLASS(s);
+ /* The message response timed out, return an error. */
+ ibe->waiting_rsp = false;
+ ibe->inbuf[1] = ibe->outbuf[1] | 0x04;
+ ibe->inbuf[2] = ibe->outbuf[2];
+ ibe->inbuf[3] = IPMI_CC_TIMEOUT;
+ k->handle_rsp(s, ibe->outbuf[0], ibe->inbuf + 1, 3);
+ } else {
+ continue_send(ibe);
+ }
+ }
+}
+
+static void addchar(IPMIBmcExtern *ibe, unsigned char ch)
+{
+ switch (ch) {
+ case VM_MSG_CHAR:
+ case VM_CMD_CHAR:
+ case VM_ESCAPE_CHAR:
+ ibe->outbuf[ibe->outlen] = VM_ESCAPE_CHAR;
+ ibe->outlen++;
+ ch |= 0x10;
+ /* No break */
+
+ default:
+ ibe->outbuf[ibe->outlen] = ch;
+ ibe->outlen++;
+ }
+}
+
+static void ipmi_bmc_extern_handle_command(IPMIBmc *b,
+ uint8_t *cmd, unsigned int cmd_len,
+ unsigned int max_cmd_len,
+ uint8_t msg_id)
+{
+ IPMIBmcExtern *ibe = IPMI_BMC_EXTERN(b);
+ IPMIInterface *s = ibe->parent.intf;
+ uint8_t err = 0, csum;
+ unsigned int i;
+
+ if (ibe->outlen) {
+ /* We already have a command queued. Shouldn't ever happen. */
+ fprintf(stderr, "IPMI KCS: Got command when not finished with the"
+ " previous commmand\n");
+ abort();
+ }
+
+ /* If it's too short or it was truncated, return an error. */
+ if (cmd_len < 2) {
+ err = IPMI_CC_REQUEST_DATA_LENGTH_INVALID;
+ } else if ((cmd_len > max_cmd_len) || (cmd_len > MAX_IPMI_MSG_SIZE)) {
+ err = IPMI_CC_REQUEST_DATA_TRUNCATED;
+ } else if (!ibe->connected) {
+ err = IPMI_CC_BMC_INIT_IN_PROGRESS;
+ }
+ if (err) {
+ IPMIInterfaceClass *k = IPMI_INTERFACE_GET_CLASS(s);
+ unsigned char rsp[3];
+ rsp[0] = cmd[0] | 0x04;
+ rsp[1] = cmd[1];
+ rsp[2] = err;
+ ibe->waiting_rsp = false;
+ k->handle_rsp(s, msg_id, rsp, 3);
+ goto out;
+ }
+
+ addchar(ibe, msg_id);
+ for (i = 0; i < cmd_len; i++) {
+ addchar(ibe, cmd[i]);
+ }
+ csum = ipmb_checksum(&msg_id, 1, 0);
+ addchar(ibe, -ipmb_checksum(cmd, cmd_len, csum));
+
+ ibe->outbuf[ibe->outlen] = VM_MSG_CHAR;
+ ibe->outlen++;
+
+ /* Start the transmit */
+ continue_send(ibe);
+
+ out:
+ return;
+}
+
+static void handle_hw_op(IPMIBmcExtern *ibe, unsigned char hw_op)
+{
+ IPMIInterface *s = ibe->parent.intf;
+ IPMIInterfaceClass *k = IPMI_INTERFACE_GET_CLASS(s);
+
+ switch (hw_op) {
+ case VM_CMD_VERSION:
+ /* We only support one version at this time. */
+ break;
+
+ case VM_CMD_NOATTN:
+ k->set_atn(s, 0, 0);
+ break;
+
+ case VM_CMD_ATTN:
+ k->set_atn(s, 1, 0);
+ break;
+
+ case VM_CMD_ATTN_IRQ:
+ k->set_atn(s, 1, 1);
+ break;
+
+ case VM_CMD_POWEROFF:
+ k->do_hw_op(s, IPMI_POWEROFF_CHASSIS, 0);
+ break;
+
+ case VM_CMD_RESET:
+ k->do_hw_op(s, IPMI_RESET_CHASSIS, 0);
+ break;
+
+ case VM_CMD_ENABLE_IRQ:
+ k->set_irq_enable(s, 1);
+ break;
+
+ case VM_CMD_DISABLE_IRQ:
+ k->set_irq_enable(s, 0);
+ break;
+
+ case VM_CMD_SEND_NMI:
+ k->do_hw_op(s, IPMI_SEND_NMI, 0);
+ break;
+ }
+}
+
+static void handle_msg(IPMIBmcExtern *ibe)
+{
+ IPMIInterfaceClass *k = IPMI_INTERFACE_GET_CLASS(ibe->parent.intf);
+
+ if (ibe->in_escape) {
+ ipmi_debug("msg escape not ended\n");
+ return;
+ }
+ if (ibe->inpos < 5) {
+ ipmi_debug("msg too short\n");
+ return;
+ }
+ if (ibe->in_too_many) {
+ ibe->inbuf[3] = IPMI_CC_REQUEST_DATA_TRUNCATED;
+ ibe->inpos = 4;
+ } else if (ipmb_checksum(ibe->inbuf, ibe->inpos, 0) != 0) {
+ ipmi_debug("msg checksum failure\n");
+ return;
+ } else {
+ ibe->inpos--; /* Remove checkum */
+ }
+
+ timer_del(ibe->extern_timer);
+ ibe->waiting_rsp = false;
+ k->handle_rsp(ibe->parent.intf, ibe->inbuf[0], ibe->inbuf + 1, ibe->inpos - 1);
+}
+
+static int can_receive(void *opaque)
+{
+ return 1;
+}
+
+static void receive(void *opaque, const uint8_t *buf, int size)
+{
+ IPMIBmcExtern *ibe = opaque;
+ int i;
+ unsigned char hw_op;
+
+ for (i = 0; i < size; i++) {
+ unsigned char ch = buf[i];
+
+ switch (ch) {
+ case VM_MSG_CHAR:
+ handle_msg(ibe);
+ ibe->in_too_many = false;
+ ibe->inpos = 0;
+ break;
+
+ case VM_CMD_CHAR:
+ if (ibe->in_too_many) {
+ ipmi_debug("cmd in too many\n");
+ ibe->in_too_many = false;
+ ibe->inpos = 0;
+ break;
+ }
+ if (ibe->in_escape) {
+ ipmi_debug("cmd in escape\n");
+ ibe->in_too_many = false;
+ ibe->inpos = 0;
+ ibe->in_escape = false;
+ break;
+ }
+ ibe->in_too_many = false;
+ if (ibe->inpos < 1) {
+ break;
+ }
+ hw_op = ibe->inbuf[0];
+ ibe->inpos = 0;
+ goto out_hw_op;
+ break;
+
+ case VM_ESCAPE_CHAR:
+ ibe->in_escape = true;
+ break;
+
+ default:
+ if (ibe->in_escape) {
+ ch &= ~0x10;
+ ibe->in_escape = false;
+ }
+ if (ibe->in_too_many) {
+ break;
+ }
+ if (ibe->inpos >= sizeof(ibe->inbuf)) {
+ ibe->in_too_many = true;
+ break;
+ }
+ ibe->inbuf[ibe->inpos] = ch;
+ ibe->inpos++;
+ break;
+ }
+ }
+ return;
+
+ out_hw_op:
+ handle_hw_op(ibe, hw_op);
+}
+
+static void chr_event(void *opaque, int event)
+{
+ IPMIBmcExtern *ibe = opaque;
+ IPMIInterface *s = ibe->parent.intf;
+ IPMIInterfaceClass *k = IPMI_INTERFACE_GET_CLASS(s);
+ unsigned char v;
+
+ switch (event) {
+ case CHR_EVENT_OPENED:
+ ibe->connected = true;
+ ibe->outpos = 0;
+ ibe->outlen = 0;
+ addchar(ibe, VM_CMD_VERSION);
+ addchar(ibe, VM_PROTOCOL_VERSION);
+ ibe->outbuf[ibe->outlen] = VM_CMD_CHAR;
+ ibe->outlen++;
+ addchar(ibe, VM_CMD_CAPABILITIES);
+ v = VM_CAPABILITIES_IRQ | VM_CAPABILITIES_ATTN;
+ if (k->do_hw_op(ibe->parent.intf, IPMI_POWEROFF_CHASSIS, 1) == 0) {
+ v |= VM_CAPABILITIES_POWER;
+ }
+ if (k->do_hw_op(ibe->parent.intf, IPMI_RESET_CHASSIS, 1) == 0) {
+ v |= VM_CAPABILITIES_RESET;
+ }
+ if (k->do_hw_op(ibe->parent.intf, IPMI_SEND_NMI, 1) == 0) {
+ v |= VM_CAPABILITIES_NMI;
+ }
+ addchar(ibe, v);
+ ibe->outbuf[ibe->outlen] = VM_CMD_CHAR;
+ ibe->outlen++;
+ ibe->sending_cmd = false;
+ continue_send(ibe);
+ break;
+
+ case CHR_EVENT_CLOSED:
+ if (!ibe->connected) {
+ return;
+ }
+ ibe->connected = false;
+ if (ibe->waiting_rsp) {
+ ibe->waiting_rsp = false;
+ ibe->inbuf[1] = ibe->outbuf[1] | 0x04;
+ ibe->inbuf[2] = ibe->outbuf[2];
+ ibe->inbuf[3] = IPMI_CC_BMC_INIT_IN_PROGRESS;
+ k->handle_rsp(s, ibe->outbuf[0], ibe->inbuf + 1, 3);
+ }
+ break;
+ }
+}
+
+static void ipmi_bmc_extern_handle_reset(IPMIBmc *b)
+{
+ IPMIBmcExtern *ibe = IPMI_BMC_EXTERN(b);
+
+ ibe->send_reset = true;
+ continue_send(ibe);
+}
+
+static void ipmi_bmc_extern_realize(DeviceState *dev, Error **errp)
+{
+ IPMIBmcExtern *ibe = IPMI_BMC_EXTERN(dev);
+
+ if (!ibe->chr) {
+ error_setg(errp, "IPMI external bmc requires chardev attribute");
+ return;
+ }
+
+ qemu_chr_add_handlers(ibe->chr, can_receive, receive, chr_event, ibe);
+}
+
+static void ipmi_bmc_extern_init(Object *obj)
+{
+ IPMIBmcExtern *ibe = IPMI_BMC_EXTERN(obj);
+
+ ibe->extern_timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, extern_timeout, ibe);
+}
+
+static Property ipmi_bmc_extern_properties[] = {
+ DEFINE_PROP_CHR("chardev", IPMIBmcExtern, chr),
+ DEFINE_PROP_END_OF_LIST(),
+};
+
+static void ipmi_bmc_extern_class_init(ObjectClass *oc, void *data)
+{
+ DeviceClass *dc = DEVICE_CLASS(oc);
+ IPMIBmcClass *bk = IPMI_BMC_CLASS(oc);
+
+ bk->handle_command = ipmi_bmc_extern_handle_command;
+ bk->handle_reset = ipmi_bmc_extern_handle_reset;
+ dc->realize = ipmi_bmc_extern_realize;
+ dc->props = ipmi_bmc_extern_properties;
+}
+
+static const TypeInfo ipmi_bmc_extern_type = {
+ .name = TYPE_IPMI_BMC_EXTERN,
+ .parent = TYPE_IPMI_BMC,
+ .instance_size = sizeof(IPMIBmcExtern),
+ .instance_init = ipmi_bmc_extern_init,
+ .class_init = ipmi_bmc_extern_class_init,
+ };
+
+static void ipmi_bmc_extern_register_types(void)
+{
+ type_register_static(&ipmi_bmc_extern_type);
+}
+
+type_init(ipmi_bmc_extern_register_types)
--
1.8.3.1
next prev parent reply other threads:[~2015-06-09 1:22 UTC|newest]
Thread overview: 31+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-06-09 1:11 [Qemu-devel] [PATCH v3 00/16] Add an IPMI device to QEMU minyard
2015-06-09 1:11 ` [Qemu-devel] [PATCH v3 01/16] Add a base IPMI interface minyard
2015-06-09 1:11 ` [Qemu-devel] [PATCH v3 02/16] ipmi: Add a local BMC simulation minyard
2015-06-09 1:11 ` minyard [this message]
2015-06-09 1:11 ` [Qemu-devel] [PATCH v3 04/16] ipmi: Add an ISA KCS low-level interface minyard
2015-06-09 1:12 ` [Qemu-devel] [PATCH v3 05/16] ipmi: Add a BT " minyard
2015-06-09 1:12 ` [Qemu-devel] [PATCH v3 06/16] ipmi: Add tests minyard
2015-06-09 1:12 ` [Qemu-devel] [PATCH v3 07/16] ipmi: Add documentation minyard
2015-06-09 1:12 ` [Qemu-devel] [PATCH v3 08/16] ipmi: Add migration capability to the IPMI devices minyard
2015-06-09 1:12 ` [Qemu-devel] [PATCH v3 09/16] ipmi: Add a firmware configuration repository minyard
2015-06-09 1:12 ` [Qemu-devel] [PATCH v3 10/16] ipmi: Add firmware registration to the ISA interface minyard
2015-06-09 1:12 ` [Qemu-devel] [PATCH v3 11/16] smbios: Add a function to directly add an entry minyard
2015-06-09 1:12 ` [Qemu-devel] [PATCH v3 12/16] pc: Postpone SMBIOS table installation to post machine init minyard
2015-07-03 8:17 ` Michael S. Tsirkin
2015-06-09 1:12 ` [Qemu-devel] [PATCH v3 13/16] ipmi: Add SMBIOS table entry minyard
2015-06-09 1:12 ` [Qemu-devel] [PATCH v3 14/16] acpi: Add a way for devices to add ACPI tables minyard
2015-07-03 8:21 ` Michael S. Tsirkin
2015-07-03 8:27 ` Michael S. Tsirkin
2015-07-07 8:08 ` Igor Mammedov
2015-07-08 17:44 ` Paolo Bonzini
2015-07-08 19:26 ` Igor Mammedov
2015-07-08 20:39 ` Paolo Bonzini
2015-07-09 8:25 ` Igor Mammedov
2015-07-13 21:55 ` Corey Minyard
2015-07-14 7:36 ` Igor Mammedov
2015-06-09 1:12 ` [Qemu-devel] [PATCH v3 15/16] ipmi: Add ACPI table entries minyard
2015-07-07 9:47 ` Igor Mammedov
2015-06-09 1:12 ` [Qemu-devel] [PATCH v3 16/16] bios: Add tests for the IPMI ACPI and SMBIOS entries minyard
2015-07-03 0:30 ` [Qemu-devel] [PATCH v3 00/16] Add an IPMI device to QEMU Benjamin Herrenschmidt
2015-07-03 6:50 ` Paolo Bonzini
2015-07-03 8:23 ` Michael S. Tsirkin
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