1524298754
between each byte either sent or received). However, most transitions actually complete in 2-3 microseconds. By polling the status register with a delay of 4us with exponential backoff, the performance of most IPMI operations is significantly improved: - A BMC update on a Supermicro x9 or x11 motherboard goes from ~1 hour to ~6-8 minutes. - An ipmitool sensor list time improves by a factor of 4. Testing showed no significant improvements on a modern server by using a lower delay. The changes should also generally reduce the total amount of CPU or I/O bandwidth used for a given IPMI operation. Submitted by: Loic Prylli <lprylli@netflix.com> Reviewed by: jhb MFC after: 2 weeks Sponsored by: Netflix Differential Revision: https://reviews.freebsd.org/D20527
639 lines
14 KiB
C
639 lines
14 KiB
C
/*-
|
|
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
|
|
*
|
|
* Copyright (c) 2006 IronPort Systems Inc. <ambrisko@ironport.com>
|
|
* All rights reserved.
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions
|
|
* are met:
|
|
* 1. Redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions and the following disclaimer.
|
|
* 2. Redistributions in binary form must reproduce the above copyright
|
|
* notice, this list of conditions and the following disclaimer in the
|
|
* documentation and/or other materials provided with the distribution.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
|
|
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
|
|
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
|
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
|
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
|
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
|
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
|
|
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
|
* SUCH DAMAGE.
|
|
*/
|
|
|
|
#include <sys/cdefs.h>
|
|
__FBSDID("$FreeBSD$");
|
|
|
|
#include <sys/param.h>
|
|
#include <sys/systm.h>
|
|
#include <sys/bus.h>
|
|
#include <sys/condvar.h>
|
|
#include <sys/eventhandler.h>
|
|
#include <sys/kernel.h>
|
|
#include <sys/kthread.h>
|
|
#include <sys/rman.h>
|
|
#include <sys/selinfo.h>
|
|
#include <machine/bus.h>
|
|
|
|
#ifdef LOCAL_MODULE
|
|
#include <ipmi.h>
|
|
#include <ipmivars.h>
|
|
#else
|
|
#include <sys/ipmi.h>
|
|
#include <dev/ipmi/ipmivars.h>
|
|
#endif
|
|
|
|
#define POLLING_DELAY_MIN 4 /* Waits are 2-3 usecs on typical systems */
|
|
#define POLLING_DELAY_MAX 256
|
|
|
|
static void kcs_clear_obf(struct ipmi_softc *, int);
|
|
static void kcs_error(struct ipmi_softc *);
|
|
static int kcs_wait_for_ibf(struct ipmi_softc *, bool);
|
|
static int kcs_wait_for_obf(struct ipmi_softc *, bool);
|
|
|
|
static int
|
|
kcs_wait(struct ipmi_softc *sc, int value, int mask)
|
|
{
|
|
int status, start = ticks;
|
|
int delay_usec = POLLING_DELAY_MIN;
|
|
|
|
status = INB(sc, KCS_CTL_STS);
|
|
while (ticks - start < MAX_TIMEOUT && (status & mask) != value) {
|
|
/*
|
|
* The wait delay is increased exponentially to avoid putting
|
|
* significant load on I/O bus.
|
|
*/
|
|
DELAY(delay_usec);
|
|
status = INB(sc, KCS_CTL_STS);
|
|
if (delay_usec < POLLING_DELAY_MAX)
|
|
delay_usec *= 2;
|
|
}
|
|
return (status);
|
|
}
|
|
|
|
static int
|
|
kcs_wait_for_ibf(struct ipmi_softc *sc, bool level)
|
|
{
|
|
|
|
return (kcs_wait(sc, level ? KCS_STATUS_IBF : 0, KCS_STATUS_IBF));
|
|
}
|
|
|
|
static int
|
|
kcs_wait_for_obf(struct ipmi_softc *sc, bool level)
|
|
{
|
|
|
|
return (kcs_wait(sc, level ? KCS_STATUS_OBF : 0, KCS_STATUS_OBF));
|
|
}
|
|
|
|
static void
|
|
kcs_clear_obf(struct ipmi_softc *sc, int status)
|
|
{
|
|
int data;
|
|
|
|
/* Clear OBF */
|
|
if (status & KCS_STATUS_OBF) {
|
|
data = INB(sc, KCS_DATA);
|
|
}
|
|
}
|
|
|
|
static void
|
|
kcs_error(struct ipmi_softc *sc)
|
|
{
|
|
int retry, status;
|
|
u_char data;
|
|
|
|
for (retry = 0; retry < 2; retry++) {
|
|
|
|
/* Wait for IBF = 0 */
|
|
status = kcs_wait_for_ibf(sc, 0);
|
|
|
|
/* ABORT */
|
|
OUTB(sc, KCS_CTL_STS, KCS_CONTROL_GET_STATUS_ABORT);
|
|
|
|
/* Wait for IBF = 0 */
|
|
status = kcs_wait_for_ibf(sc, 0);
|
|
|
|
/* Clear OBF */
|
|
kcs_clear_obf(sc, status);
|
|
|
|
if (status & KCS_STATUS_OBF) {
|
|
data = INB(sc, KCS_DATA);
|
|
if (data != 0)
|
|
device_printf(sc->ipmi_dev,
|
|
"KCS Error Data %02x\n", data);
|
|
}
|
|
|
|
/* 0x00 to DATA_IN */
|
|
OUTB(sc, KCS_DATA, 0x00);
|
|
|
|
/* Wait for IBF = 0 */
|
|
status = kcs_wait_for_ibf(sc, 0);
|
|
|
|
if (KCS_STATUS_STATE(status) == KCS_STATUS_STATE_READ) {
|
|
|
|
/* Wait for OBF = 1 */
|
|
status = kcs_wait_for_obf(sc, 1);
|
|
|
|
/* Read error status */
|
|
data = INB(sc, KCS_DATA);
|
|
if (data != 0 && (data != 0xff || bootverbose))
|
|
device_printf(sc->ipmi_dev, "KCS error: %02x\n",
|
|
data);
|
|
|
|
/* Write READ into Data_in */
|
|
OUTB(sc, KCS_DATA, KCS_DATA_IN_READ);
|
|
|
|
/* Wait for IBF = 0 */
|
|
status = kcs_wait_for_ibf(sc, 0);
|
|
}
|
|
|
|
/* IDLE STATE */
|
|
if (KCS_STATUS_STATE(status) == KCS_STATUS_STATE_IDLE) {
|
|
/* Wait for OBF = 1 */
|
|
status = kcs_wait_for_obf(sc, 1);
|
|
|
|
/* Clear OBF */
|
|
kcs_clear_obf(sc, status);
|
|
return;
|
|
}
|
|
}
|
|
device_printf(sc->ipmi_dev, "KCS: Error retry exhausted\n");
|
|
}
|
|
|
|
/*
|
|
* Start to write a request. Waits for IBF to clear and then sends the
|
|
* WR_START command.
|
|
*/
|
|
static int
|
|
kcs_start_write(struct ipmi_softc *sc)
|
|
{
|
|
int retry, status;
|
|
|
|
for (retry = 0; retry < 10; retry++) {
|
|
/* Wait for IBF = 0 */
|
|
status = kcs_wait_for_ibf(sc, 0);
|
|
if (status & KCS_STATUS_IBF)
|
|
return (0);
|
|
|
|
/* Clear OBF */
|
|
kcs_clear_obf(sc, status);
|
|
|
|
/* Write start to command */
|
|
OUTB(sc, KCS_CTL_STS, KCS_CONTROL_WRITE_START);
|
|
|
|
/* Wait for IBF = 0 */
|
|
status = kcs_wait_for_ibf(sc, 0);
|
|
if (status & KCS_STATUS_IBF)
|
|
return (0);
|
|
|
|
if (KCS_STATUS_STATE(status) == KCS_STATUS_STATE_WRITE)
|
|
break;
|
|
DELAY(1000000);
|
|
}
|
|
|
|
if (KCS_STATUS_STATE(status) != KCS_STATUS_STATE_WRITE)
|
|
/* error state */
|
|
return (0);
|
|
|
|
/* Clear OBF */
|
|
kcs_clear_obf(sc, status);
|
|
|
|
return (1);
|
|
}
|
|
|
|
/*
|
|
* Write a byte of the request message, excluding the last byte of the
|
|
* message which requires special handling.
|
|
*/
|
|
static int
|
|
kcs_write_byte(struct ipmi_softc *sc, u_char data)
|
|
{
|
|
int status;
|
|
|
|
/* Data to Data */
|
|
OUTB(sc, KCS_DATA, data);
|
|
|
|
/* Wait for IBF = 0 */
|
|
status = kcs_wait_for_ibf(sc, 0);
|
|
if (status & KCS_STATUS_IBF)
|
|
return (0);
|
|
|
|
if (KCS_STATUS_STATE(status) != KCS_STATUS_STATE_WRITE)
|
|
return (0);
|
|
|
|
/* Clear OBF */
|
|
kcs_clear_obf(sc, status);
|
|
return (1);
|
|
}
|
|
|
|
/*
|
|
* Write the last byte of a request message.
|
|
*/
|
|
static int
|
|
kcs_write_last_byte(struct ipmi_softc *sc, u_char data)
|
|
{
|
|
int status;
|
|
|
|
/* Write end to command */
|
|
OUTB(sc, KCS_CTL_STS, KCS_CONTROL_WRITE_END);
|
|
|
|
/* Wait for IBF = 0 */
|
|
status = kcs_wait_for_ibf(sc, 0);
|
|
if (status & KCS_STATUS_IBF)
|
|
return (0);
|
|
|
|
if (KCS_STATUS_STATE(status) != KCS_STATUS_STATE_WRITE)
|
|
/* error state */
|
|
return (0);
|
|
|
|
/* Clear OBF */
|
|
kcs_clear_obf(sc, status);
|
|
|
|
/* Send data byte to DATA. */
|
|
OUTB(sc, KCS_DATA, data);
|
|
return (1);
|
|
}
|
|
|
|
/*
|
|
* Read one byte of the reply message.
|
|
*/
|
|
static int
|
|
kcs_read_byte(struct ipmi_softc *sc, u_char *data)
|
|
{
|
|
int status;
|
|
u_char dummy;
|
|
|
|
/* Wait for IBF = 0 */
|
|
status = kcs_wait_for_ibf(sc, 0);
|
|
|
|
/* Read State */
|
|
if (KCS_STATUS_STATE(status) == KCS_STATUS_STATE_READ) {
|
|
|
|
/* Wait for OBF = 1 */
|
|
status = kcs_wait_for_obf(sc, 1);
|
|
if ((status & KCS_STATUS_OBF) == 0)
|
|
return (0);
|
|
|
|
/* Read Data_out */
|
|
*data = INB(sc, KCS_DATA);
|
|
|
|
/* Write READ into Data_in */
|
|
OUTB(sc, KCS_DATA, KCS_DATA_IN_READ);
|
|
return (1);
|
|
}
|
|
|
|
/* Idle State */
|
|
if (KCS_STATUS_STATE(status) == KCS_STATUS_STATE_IDLE) {
|
|
|
|
/* Wait for OBF = 1*/
|
|
status = kcs_wait_for_obf(sc, 1);
|
|
if ((status & KCS_STATUS_OBF) == 0)
|
|
return (0);
|
|
|
|
/* Read Dummy */
|
|
dummy = INB(sc, KCS_DATA);
|
|
return (2);
|
|
}
|
|
|
|
/* Error State */
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* Send a request message and collect the reply. Returns true if we
|
|
* succeed.
|
|
*/
|
|
static int
|
|
kcs_polled_request(struct ipmi_softc *sc, struct ipmi_request *req)
|
|
{
|
|
u_char *cp, data;
|
|
int i, state;
|
|
|
|
IPMI_IO_LOCK(sc);
|
|
|
|
/* Send the request. */
|
|
if (!kcs_start_write(sc)) {
|
|
device_printf(sc->ipmi_dev, "KCS: Failed to start write\n");
|
|
goto fail;
|
|
}
|
|
#ifdef KCS_DEBUG
|
|
device_printf(sc->ipmi_dev, "KCS: WRITE_START... ok\n");
|
|
#endif
|
|
|
|
if (!kcs_write_byte(sc, req->ir_addr)) {
|
|
device_printf(sc->ipmi_dev, "KCS: Failed to write address\n");
|
|
goto fail;
|
|
}
|
|
#ifdef KCS_DEBUG
|
|
device_printf(sc->ipmi_dev, "KCS: Wrote address: %02x\n", req->ir_addr);
|
|
#endif
|
|
|
|
if (req->ir_requestlen == 0) {
|
|
if (!kcs_write_last_byte(sc, req->ir_command)) {
|
|
device_printf(sc->ipmi_dev,
|
|
"KCS: Failed to write command\n");
|
|
goto fail;
|
|
}
|
|
#ifdef KCS_DEBUG
|
|
device_printf(sc->ipmi_dev, "KCS: Wrote command: %02x\n",
|
|
req->ir_command);
|
|
#endif
|
|
} else {
|
|
if (!kcs_write_byte(sc, req->ir_command)) {
|
|
device_printf(sc->ipmi_dev,
|
|
"KCS: Failed to write command\n");
|
|
goto fail;
|
|
}
|
|
#ifdef KCS_DEBUG
|
|
device_printf(sc->ipmi_dev, "KCS: Wrote command: %02x\n",
|
|
req->ir_command);
|
|
#endif
|
|
|
|
cp = req->ir_request;
|
|
for (i = 0; i < req->ir_requestlen - 1; i++) {
|
|
if (!kcs_write_byte(sc, *cp++)) {
|
|
device_printf(sc->ipmi_dev,
|
|
"KCS: Failed to write data byte %d\n",
|
|
i + 1);
|
|
goto fail;
|
|
}
|
|
#ifdef KCS_DEBUG
|
|
device_printf(sc->ipmi_dev, "KCS: Wrote data: %02x\n",
|
|
cp[-1]);
|
|
#endif
|
|
}
|
|
|
|
if (!kcs_write_last_byte(sc, *cp)) {
|
|
device_printf(sc->ipmi_dev,
|
|
"KCS: Failed to write last dta byte\n");
|
|
goto fail;
|
|
}
|
|
#ifdef KCS_DEBUG
|
|
device_printf(sc->ipmi_dev, "KCS: Wrote last data: %02x\n",
|
|
*cp);
|
|
#endif
|
|
}
|
|
|
|
/* Read the reply. First, read the NetFn/LUN. */
|
|
if (kcs_read_byte(sc, &data) != 1) {
|
|
device_printf(sc->ipmi_dev, "KCS: Failed to read address\n");
|
|
goto fail;
|
|
}
|
|
#ifdef KCS_DEBUG
|
|
device_printf(sc->ipmi_dev, "KCS: Read address: %02x\n", data);
|
|
#endif
|
|
if (data != IPMI_REPLY_ADDR(req->ir_addr)) {
|
|
device_printf(sc->ipmi_dev, "KCS: Reply address mismatch\n");
|
|
goto fail;
|
|
}
|
|
|
|
/* Next we read the command. */
|
|
if (kcs_read_byte(sc, &data) != 1) {
|
|
device_printf(sc->ipmi_dev, "KCS: Failed to read command\n");
|
|
goto fail;
|
|
}
|
|
#ifdef KCS_DEBUG
|
|
device_printf(sc->ipmi_dev, "KCS: Read command: %02x\n", data);
|
|
#endif
|
|
if (data != req->ir_command) {
|
|
device_printf(sc->ipmi_dev, "KCS: Command mismatch\n");
|
|
goto fail;
|
|
}
|
|
|
|
/* Next we read the completion code. */
|
|
if (kcs_read_byte(sc, &req->ir_compcode) != 1) {
|
|
if (bootverbose) {
|
|
device_printf(sc->ipmi_dev,
|
|
"KCS: Failed to read completion code\n");
|
|
}
|
|
goto fail;
|
|
}
|
|
#ifdef KCS_DEBUG
|
|
device_printf(sc->ipmi_dev, "KCS: Read completion code: %02x\n",
|
|
req->ir_compcode);
|
|
#endif
|
|
|
|
/* Finally, read the reply from the BMC. */
|
|
i = 0;
|
|
for (;;) {
|
|
state = kcs_read_byte(sc, &data);
|
|
if (state == 0) {
|
|
device_printf(sc->ipmi_dev,
|
|
"KCS: Read failed on byte %d\n", i + 1);
|
|
goto fail;
|
|
}
|
|
if (state == 2)
|
|
break;
|
|
if (i < req->ir_replybuflen) {
|
|
req->ir_reply[i] = data;
|
|
#ifdef KCS_DEBUG
|
|
device_printf(sc->ipmi_dev, "KCS: Read data %02x\n",
|
|
data);
|
|
} else {
|
|
device_printf(sc->ipmi_dev,
|
|
"KCS: Read short %02x byte %d\n", data, i + 1);
|
|
#endif
|
|
}
|
|
i++;
|
|
}
|
|
IPMI_IO_UNLOCK(sc);
|
|
req->ir_replylen = i;
|
|
#ifdef KCS_DEBUG
|
|
device_printf(sc->ipmi_dev, "KCS: READ finished (%d bytes)\n", i);
|
|
if (req->ir_replybuflen < i)
|
|
#else
|
|
if (req->ir_replybuflen < i && req->ir_replybuflen != 0)
|
|
#endif
|
|
device_printf(sc->ipmi_dev,
|
|
"KCS: Read short: %zd buffer, %d actual\n",
|
|
req->ir_replybuflen, i);
|
|
return (1);
|
|
fail:
|
|
kcs_error(sc);
|
|
IPMI_IO_UNLOCK(sc);
|
|
return (0);
|
|
}
|
|
|
|
static void
|
|
kcs_loop(void *arg)
|
|
{
|
|
struct ipmi_softc *sc = arg;
|
|
struct ipmi_request *req;
|
|
int i, ok;
|
|
|
|
IPMI_LOCK(sc);
|
|
while ((req = ipmi_dequeue_request(sc)) != NULL) {
|
|
IPMI_UNLOCK(sc);
|
|
ok = 0;
|
|
for (i = 0; i < 3 && !ok; i++)
|
|
ok = kcs_polled_request(sc, req);
|
|
if (ok)
|
|
req->ir_error = 0;
|
|
else
|
|
req->ir_error = EIO;
|
|
IPMI_LOCK(sc);
|
|
ipmi_complete_request(sc, req);
|
|
}
|
|
IPMI_UNLOCK(sc);
|
|
kproc_exit(0);
|
|
}
|
|
|
|
static int
|
|
kcs_startup(struct ipmi_softc *sc)
|
|
{
|
|
|
|
return (kproc_create(kcs_loop, sc, &sc->ipmi_kthread, 0, 0, "%s: kcs",
|
|
device_get_nameunit(sc->ipmi_dev)));
|
|
}
|
|
|
|
static int
|
|
kcs_driver_request(struct ipmi_softc *sc, struct ipmi_request *req, int timo)
|
|
{
|
|
int i, ok;
|
|
|
|
ok = 0;
|
|
for (i = 0; i < 3 && !ok; i++)
|
|
ok = kcs_polled_request(sc, req);
|
|
if (ok)
|
|
req->ir_error = 0;
|
|
else
|
|
req->ir_error = EIO;
|
|
return (req->ir_error);
|
|
}
|
|
|
|
int
|
|
ipmi_kcs_attach(struct ipmi_softc *sc)
|
|
{
|
|
int status;
|
|
|
|
/* Setup function pointers. */
|
|
sc->ipmi_startup = kcs_startup;
|
|
sc->ipmi_enqueue_request = ipmi_polled_enqueue_request;
|
|
sc->ipmi_driver_request = kcs_driver_request;
|
|
sc->ipmi_driver_requests_polled = 1;
|
|
|
|
/* See if we can talk to the controller. */
|
|
status = INB(sc, KCS_CTL_STS);
|
|
if (status == 0xff) {
|
|
device_printf(sc->ipmi_dev, "couldn't find it\n");
|
|
return (ENXIO);
|
|
}
|
|
|
|
#ifdef KCS_DEBUG
|
|
device_printf(sc->ipmi_dev, "KCS: initial state: %02x\n", status);
|
|
#endif
|
|
if (status & KCS_STATUS_OBF ||
|
|
KCS_STATUS_STATE(status) != KCS_STATUS_STATE_IDLE)
|
|
kcs_error(sc);
|
|
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* Determine the alignment automatically for a PCI attachment. In this case,
|
|
* any unused bytes will return 0x00 when read. We make use of the C/D bit
|
|
* in the CTL_STS register to try to start a GET_STATUS transaction. When
|
|
* we write the command, that bit should be set, so we should get a non-zero
|
|
* value back when we read CTL_STS if the offset we are testing is the CTL_STS
|
|
* register.
|
|
*/
|
|
int
|
|
ipmi_kcs_probe_align(struct ipmi_softc *sc)
|
|
{
|
|
int data, status;
|
|
|
|
sc->ipmi_io_spacing = 1;
|
|
retry:
|
|
#ifdef KCS_DEBUG
|
|
device_printf(sc->ipmi_dev, "Trying KCS align %d... ", sc->ipmi_io_spacing);
|
|
#endif
|
|
|
|
/* Wait for IBF = 0 */
|
|
status = INB(sc, KCS_CTL_STS);
|
|
while (status & KCS_STATUS_IBF) {
|
|
DELAY(100);
|
|
status = INB(sc, KCS_CTL_STS);
|
|
}
|
|
|
|
OUTB(sc, KCS_CTL_STS, KCS_CONTROL_GET_STATUS_ABORT);
|
|
|
|
/* Wait for IBF = 0 */
|
|
status = INB(sc, KCS_CTL_STS);
|
|
while (status & KCS_STATUS_IBF) {
|
|
DELAY(100);
|
|
status = INB(sc, KCS_CTL_STS);
|
|
}
|
|
|
|
/* If we got 0x00 back, then this must not be the CTL_STS register. */
|
|
if (status == 0) {
|
|
#ifdef KCS_DEBUG
|
|
printf("failed\n");
|
|
#endif
|
|
sc->ipmi_io_spacing <<= 1;
|
|
if (sc->ipmi_io_spacing > 4)
|
|
return (0);
|
|
goto retry;
|
|
}
|
|
#ifdef KCS_DEBUG
|
|
printf("ok\n");
|
|
#endif
|
|
|
|
/* Finish out the transaction. */
|
|
|
|
/* Clear OBF */
|
|
if (status & KCS_STATUS_OBF)
|
|
data = INB(sc, KCS_DATA);
|
|
|
|
/* 0x00 to DATA_IN */
|
|
OUTB(sc, KCS_DATA, 0);
|
|
|
|
/* Wait for IBF = 0 */
|
|
status = INB(sc, KCS_CTL_STS);
|
|
while (status & KCS_STATUS_IBF) {
|
|
DELAY(100);
|
|
status = INB(sc, KCS_CTL_STS);
|
|
}
|
|
|
|
if (KCS_STATUS_STATE(status) == KCS_STATUS_STATE_READ) {
|
|
/* Wait for IBF = 1 */
|
|
while (!(status & KCS_STATUS_OBF)) {
|
|
DELAY(100);
|
|
status = INB(sc, KCS_CTL_STS);
|
|
}
|
|
|
|
/* Read error status. */
|
|
data = INB(sc, KCS_DATA);
|
|
|
|
/* Write dummy READ to DATA_IN. */
|
|
OUTB(sc, KCS_DATA, KCS_DATA_IN_READ);
|
|
|
|
/* Wait for IBF = 0 */
|
|
status = INB(sc, KCS_CTL_STS);
|
|
while (status & KCS_STATUS_IBF) {
|
|
DELAY(100);
|
|
status = INB(sc, KCS_CTL_STS);
|
|
}
|
|
}
|
|
|
|
if (KCS_STATUS_STATE(status) == KCS_STATUS_STATE_IDLE) {
|
|
/* Wait for IBF = 1 */
|
|
while (!(status & KCS_STATUS_OBF)) {
|
|
DELAY(100);
|
|
status = INB(sc, KCS_CTL_STS);
|
|
}
|
|
|
|
/* Clear OBF */
|
|
if (status & KCS_STATUS_OBF)
|
|
data = INB(sc, KCS_DATA);
|
|
} else
|
|
device_printf(sc->ipmi_dev, "KCS probe: end state %x\n",
|
|
KCS_STATUS_STATE(status));
|
|
|
|
return (1);
|
|
}
|