/*
* ipmi_smic_sm.c
*
* The state-machine driver for an IPMI SMIC driver
*
* It started as a copy of Corey Minyard's driver for the KSC interface
* and the kernel patch "mmcdev-patch-245" by HP
*
* modified by: Hannes Schulz <schulz@schwaar.com>
* ipmi@schwaar.com
*
*
* Corey Minyard's driver for the KSC interface has the following
* copyright notice:
* Copyright 2002 MontaVista Software Inc.
*
* the kernel patch "mmcdev-patch-245" by HP has the following
* copyright notice:
* (c) Copyright 2001 Grant Grundler (c) Copyright
* 2001 Hewlett-Packard Company
*
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation; either version 2 of the License, or (at your
* option) any later version.
*
*
* THIS SOFTWARE IS PROVIDED ``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 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.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 675 Mass Ave, Cambridge, MA 02139, USA. */
#include <linux/kernel.h> /* For printk. */
#include <linux/string.h>
#include <linux/ipmi_msgdefs.h> /* for completion codes */
#include "ipmi_si_sm.h"
/* smic_debug is a bit-field
* SMIC_DEBUG_ENABLE - turned on for now
* SMIC_DEBUG_MSG - commands and their responses
* SMIC_DEBUG_STATES - state machine
*/
#define SMIC_DEBUG_STATES 4
#define SMIC_DEBUG_MSG 2
#define SMIC_DEBUG_ENABLE 1
static int smic_debug = 1;
enum smic_states {
SMIC_IDLE,
SMIC_START_OP,
SMIC_OP_OK,
SMIC_WRITE_START,
SMIC_WRITE_NEXT,
SMIC_WRITE_END,
SMIC_WRITE2READ,
SMIC_READ_START,
SMIC_READ_NEXT,
SMIC_READ_END,
SMIC_HOSED
};
#define MAX_SMIC_READ_SIZE 80
#define MAX_SMIC_WRITE_SIZE 80
#define SMIC_MAX_ERROR_RETRIES 3
/* Timeouts in microseconds. */
#define SMIC_RETRY_TIMEOUT 100000
/* SMIC Flags Register Bits */
#define SMIC_RX_DATA_READY 0x80
#define SMIC_TX_DATA_READY 0x40
#define SMIC_SMI 0x10
#define SMIC_EVM_DATA_AVAIL 0x08
#define SMIC_SMS_DATA_AVAIL 0x04
#define SMIC_FLAG_BSY 0x01
/* SMIC Error Codes */
#define EC_NO_ERROR 0x00
#define EC_ABORTED 0x01
#define EC_ILLEGAL_CONTROL 0x02
#define EC_NO_RESPONSE 0x03
#define EC_ILLEGAL_COMMAND 0x04
#define EC_BUFFER_FULL 0x05
struct si_sm_data
{
enum smic_states state;
struct si_sm_io *io;
unsigned char write_data[MAX_SMIC_WRITE_SIZE];
int write_pos;
int write_count;
int orig_write_count;
unsigned char read_data[MAX_SMIC_READ_SIZE];
int read_pos;
int truncated;
unsigned int error_retries;
long smic_timeout;
};
static unsigned int init_smic_data (struct si_sm_data *smic,
struct si_sm_io *io)
{
smic->state = SMIC_IDLE;
smic->io = io;
smic->write_pos = 0;
smic->write_count = 0;
smic->orig_write_count = 0;
smic->read_pos = 0;
smic->error_retries = 0;
smic->truncated = 0;
smic->smic_timeout = SMIC_RETRY_TIMEOUT;
/* We use 3 bytes of I/O. */
return 3;
}
static int start_smic_transaction(struct si_sm_data *smic,
unsigned char *data, unsigned int size)
{
unsigned int i;
if ((size < 2) || (size > MAX_SMIC_WRITE_SIZE)) {
return -1;
}
if ((smic->state != SMIC_IDLE) && (smic->state != SMIC_HOSED)) {
return -2;
}
if (smic_debug & SMIC_DEBUG_MSG) {
printk(KERN_INFO "start_smic_transaction -");
for (i = 0; i < size; i ++) {
printk (" %02x", (unsigned char) (data [i]));
}
printk ("\n");
}
smic->error_retries = 0;
memcpy(smic->write_data, data, size);
smic->write_count = size;
smic->orig_write_count = size;
smic->write_pos = 0;
smic->read_pos = 0;
smic->state = SMIC_START_OP;
smic->smic_timeout = SMIC_RETRY_TIMEOUT;
return 0;
}
static int smic_get_result(struct si_sm_data *smic,
unsigned char *data, unsigned int length)
{
int i;
if (smic_debug & SMIC_DEBUG_MSG) {
printk (KERN_INFO "smic_get result -");
for (i = 0; i < smic->read_pos; i ++) {
printk (" %02x", (smic->read_data [i]));
}
printk ("\n");
}
if (length < smic->read_pos) {
smic->read_pos = length;
smic->truncated = 1;
}
memcpy(data, smic->read_data, smic->read_pos);
if ((length >= 3) && (smic->read_pos < 3)) {
data[2] = IPMI_ERR_UNSPECIFIED;
smic->read_pos = 3;
}
if (smic->truncated) {
data[2] = IPMI_ERR_MSG_TRUNCATED;
smic->truncated = 0;
}
return smic->read_pos;
}
static inline unsigned char read_smic_flags(struct si_sm_data *smic)
{
return smic->io->inputb(smic->io, 2);
}
static inline unsigned char read_smic_status(struct si_sm_data *smic)
{
return smic->io->inputb(smic->io, 1);
}
static inline unsigned char read_smic_data(struct si_sm_data *smic)
{
return smic->io->inputb(smic->io, 0);
}
static inline void write_smic_flags(struct si_sm_data *smic,
unsigned char flags)
{
smic->io->outputb(smic->io, 2, flags);
}
static inline void write_smic_control(struct si_sm_data *smic,
unsigned char control)
{
smic->io->outputb(smic->io, 1, control);
}
static inline void write_si_sm_data (struct si_sm_data *smic,
unsigned char data)
{
smic->io->outputb(smic->io, 0, data);
}
static inline void start_error_recovery(struct si_sm_data *smic, char *reason)
{
(smic->error_retries)++;
if (smic->error_retries > SMIC_MAX_ERROR_RETRIES) {
if (smic_debug & SMIC_DEBUG_ENABLE) {
printk(KERN_WARNING
"ipmi_smic_drv: smic hosed: %s\n", reason);
}
smic->state = SMIC_HOSED;
} else {
smic->write_count = smic->orig_write_count;
smic->write_pos = 0;
smic->read_pos = 0;
smic->state = SMIC_START_OP;
smic->smic_timeout = SMIC_RETRY_TIMEOUT;
}
}
static inline void write_next_byte(struct si_sm_data *smic)
{
write_si_sm_data(smic, smic->write_data[smic->write_pos]);
(smic->write_pos)++;
(smic->write_count)--;
}
static inline void read_next_byte (struct si_sm_data *smic)
{
if (smic->read_pos >= MAX_SMIC_READ_SIZE) {
read_smic_data (smic);
smic->truncated = 1;
} else {
smic->read_data[smic->read_pos] = read_smic_data(smic);
(smic->read_pos)++;
}
}
/* SMIC Control/Status Code Components */
#define SMIC_GET_STATUS 0x00 /* Control form's name */
#define SMIC_READY 0x00 /* Status form's name */
#define SMIC_WR_START 0x01 /* Unified Control/Status names... */
#define SMIC_WR_NEXT 0x02
#define SMIC_WR_END 0x03
#define SMIC_RD_START 0x04
#define SMIC_RD_NEXT 0x05
#define SMIC_RD_END 0x06
#define SMIC_CODE_MASK 0x0f
#define SMIC_CONTROL 0x00
#define SMIC_STATUS 0x80
#define SMIC_CS_MASK 0x80
#define SMIC_SMS 0x40
#define SMIC_SMM 0x60
#define SMIC_STREAM_MASK 0x60
/* SMIC Control Codes */
#define SMIC_CC_SMS_GET_STATUS (SMIC_CONTROL|SMIC_SMS|SMIC_GET_STATUS)
#define SMIC_CC_SMS_WR_START (SMIC_CONTROL|SMIC_SMS|SMIC_WR_START)
#define SMIC_CC_SMS_WR_NEXT (SMIC_CONTROL|SMIC_SMS|SMIC_WR_NEXT)
#define SMIC_CC_SMS_WR_END (SMIC_CONTROL|SMIC_SMS|SMIC_WR_END)
#define SMIC_CC_SMS_RD_START (SMIC_CONTROL|SMIC_SMS|SMIC_RD_START)
#define SMIC_CC_SMS_RD_NEXT (SMIC_CONTROL|SMIC_SMS|SMIC_RD_NEXT)
#define SMIC_CC_SMS_RD_END (SMIC_CONTROL|SMIC_SMS|SMIC_RD_END)
#define SMIC_CC_SMM_GET_STATUS (SMIC_CONTROL|SMIC_SMM|SMIC_GET_STATUS)
#define SMIC_CC_SMM_WR_START (SMIC_CONTROL|SMIC_SMM|SMIC_WR_START)
#define SMIC_CC_SMM_WR_NEXT (SMIC_CONTROL|SMIC_SMM|SMIC_WR_NEXT)
#define SMIC_CC_SMM_WR_END (SMIC_CONTROL|SMIC_SMM|SMIC_WR_END)
#define SMIC_CC_SMM_RD_START (SMIC_CONTROL|SMIC_SMM|SMIC_RD_START)
#define SMIC_CC_SMM_RD_NEXT (SMIC_CONTROL|SMIC_SMM|SMIC_RD_NEXT)
#define SMIC_CC_SMM_RD_END (SMIC_CONTROL|SMIC_SMM|SMIC_RD_END)
/* SMIC Status Codes */
#define SMIC_SC_SMS_READY (SMIC_STATUS|SMIC_SMS|SMIC_READY)
#define SMIC_SC_SMS_WR_START (SMIC_STATUS|SMIC_SMS|SMIC_WR_START)
#define SMIC_SC_SMS_WR_NEXT (SMIC_STATUS|SMIC_SMS|SMIC_WR_NEXT)
#define SMIC_SC_SMS_WR_END (SMIC_STATUS|SMIC_SMS|SMIC_WR_END)
#define SMIC_SC_SMS_RD_START (SMIC_STATUS|SMIC_SMS|SMIC_RD_START)
#define SMIC_SC_SMS_RD_NEXT (SMIC_STATUS|SMIC_SMS|SMIC_RD_NEXT)
#define SMIC_SC_SMS_RD_END (SMIC_STATUS|SMIC_SMS|SMIC_RD_END)
#define SMIC_SC_SMM_READY (SMIC_STATUS|SMIC_SMM|SMIC_READY)
#define SMIC_SC_SMM_WR_START (SMIC_STATUS|SMIC_SMM|SMIC_WR_START)
#define SMIC_SC_SMM_WR_NEXT (SMIC_STATUS|SMIC_SMM|SMIC_WR_NEXT)
#define SMIC_SC_SMM_WR_END (SMIC_STATUS|SMIC_SMM|SMIC_WR_END)
#define SMIC_SC_SMM_RD_START (SMIC_STATUS|SMIC_SMM|SMIC_RD_START)
#define SMIC_SC_SMM_RD_NEXT (SMIC_STATUS|SMIC_SMM|SMIC_RD_NEXT)
#define SMIC_SC_SMM_RD_END (SMIC_STATUS|SMIC_SMM|SMIC_RD_END)
/* these are the control/status codes we actually use
SMIC_CC_SMS_GET_STATUS 0x40
SMIC_CC_SMS_WR_START 0x41
SMIC_CC_SMS_WR_NEXT 0x42
SMIC_CC_SMS_WR_END 0x43
SMIC_CC_SMS_RD_START 0x44
SMIC_CC_SMS_RD_NEXT 0x45
SMIC_CC_SMS_RD_END 0x46
SMIC_SC_SMS_READY 0xC0
SMIC_SC_SMS_WR_START 0xC1
SMIC_SC_SMS_WR_NEXT 0xC2
SMIC_SC_SMS_WR_END 0xC3
SMIC_SC_SMS_RD_START 0xC4
SMIC_SC_SMS_RD_NEXT 0xC5
SMIC_SC_SMS_RD_END 0xC6
*/
static enum si_sm_result smic_event (struct si_sm_data *smic, long time)
{
unsigned char status;
unsigned char flags;
unsigned char data;
if (smic->state == SMIC_HOSED) {
init_smic_data(smic, smic->io);
return SI_SM_HOSED;
}
if (smic->state != SMIC_IDLE) {
if (smic_debug & SMIC_DEBUG_STATES) {
printk(KERN_INFO
"smic_event - smic->smic_timeout = %ld,"
" time = %ld\n",
smic->smic_timeout, time);
}
/* FIXME: smic_event is sometimes called with time > SMIC_RETRY_TIMEOUT */
if (time < SMIC_RETRY_TIMEOUT) {
smic->smic_timeout -= time;
if (smic->smic_timeout < 0) {
start_error_recovery(smic, "smic timed out.");
return SI_SM_CALL_WITH_DELAY;
}
}
}
flags = read_smic_flags(smic);
if (flags & SMIC_FLAG_BSY)
return SI_SM_CALL_WITH_DELAY;
status = read_smic_status (smic);
if (smic_debug & SMIC_DEBUG_STATES)
printk(KERN_INFO
"smic_event - state = %d, flags = 0x%02x,"
" status = 0x%02x\n",
smic->state, flags, status);
switch (smic->state) {
case SMIC_IDLE:
/* in IDLE we check for available messages */
if (flags & (SMIC_SMI |
SMIC_EVM_DATA_AVAIL | SMIC_SMS_DATA_AVAIL))
{
return SI_SM_ATTN;
}
return SI_SM_IDLE;
case SMIC_START_OP:
/* sanity check whether smic is really idle */
write_smic_control(smic, SMIC_CC_SMS_GET_STATUS);
write_smic_flags(smic, flags | SMIC_FLAG_BSY);
smic->state = SMIC_OP_OK;
break;
case SMIC_OP_OK:
if (status != SMIC_SC_SMS_READY) {
/* this should not happen */
start_error_recovery(smic,
"state = SMIC_OP_OK,"
" status != SMIC_SC_SMS_READY");
return SI_SM_CALL_WITH_DELAY;
}
/* OK so far; smic is idle let us start ... */
write_smic_control(smic, SMIC_CC_SMS_WR_START);
write_next_byte(smic);
write_smic_flags(smic, flags | SMIC_FLAG_BSY);
smic->state = SMIC_WRITE_START;
break;
case SMIC_WRITE_START:
if (status != SMIC_SC_SMS_WR_START) {
start_error_recovery(smic,
"state = SMIC_WRITE_START, "
"status != SMIC_SC_SMS_WR_START");
return SI_SM_CALL_WITH_DELAY;
}
/* we must not issue WR_(NEXT|END) unless
TX_DATA_READY is set */
if (flags & SMIC_TX_DATA_READY) {
if (smic->write_count == 1) {
/* last byte */
write_smic_control(smic, SMIC_CC_SMS_WR_END);
smic->state = SMIC_WRITE_END;
} else {
write_smic_control(smic, SMIC_CC_SMS_WR_NEXT);
smic->state = SMIC_WRITE_NEXT;
}
write_next_byte(smic);
write_smic_flags(smic, flags | SMIC_FLAG_BSY);
}
else {
return SI_SM_CALL_WITH_DELAY;
}
break;
case SMIC_WRITE_NEXT:
if (status != SMIC_SC_SMS_WR_NEXT) {
start_error_recovery(smic,
"state = SMIC_WRITE_NEXT, "
"status != SMIC_SC_SMS_WR_NEXT");
return SI_SM_CALL_WITH_DELAY;
}
/* this is the same code as in SMIC_WRITE_START */
if (flags & SMIC_TX_DATA_READY) {
if (smic->write_count == 1) {
write_smic_control(smic, SMIC_CC_SMS_WR_END);
smic->state = SMIC_WRITE_END;
}
else {
write_smic_control(smic, SMIC_CC_SMS_WR_NEXT);
smic->state = SMIC_WRITE_NEXT;
}
write_next_byte(smic);
write_smic_flags(smic, flags | SMIC_FLAG_BSY);
}
else {
return SI_SM_CALL_WITH_DELAY;
}
break;
case SMIC_WRITE_END:
if (status != SMIC_SC_SMS_WR_END) {
start_error_recovery (smic,
"state = SMIC_WRITE_END, "
"status != SMIC_SC_SMS_WR_END");
return SI_SM_CALL_WITH_DELAY;
}
/* data register holds an error code */
data = read_smic_data(smic);
if (data != 0) {
if (smic_debug & SMIC_DEBUG_ENABLE) {
printk(KERN_INFO
"SMIC_WRITE_END: data = %02x\n", data);
}
start_error_recovery(smic,
"state = SMIC_WRITE_END, "
"data != SUCCESS");
return SI_SM_CALL_WITH_DELAY;
} else {
smic->state = SMIC_WRITE2READ;
}
break;
case SMIC_WRITE2READ:
/* we must wait for RX_DATA_READY to be set before we
can continue */
if (flags & SMIC_RX_DATA_READY) {
write_smic_control(smic, SMIC_CC_SMS_RD_START);
write_smic_flags(smic, flags | SMIC_FLAG_BSY);
smic->state = SMIC_READ_START;
} else {
return SI_SM_CALL_WITH_DELAY;
}
break;
case SMIC_READ_START:
if (status != SMIC_SC_SMS_RD_START) {
start_error_recovery(smic,
"state = SMIC_READ_START, "
"status != SMIC_SC_SMS_RD_START");
return SI_SM_CALL_WITH_DELAY;
}
if (flags & SMIC_RX_DATA_READY) {
read_next_byte(smic);
write_smic_control(smic, SMIC_CC_SMS_RD_NEXT);
write_smic_flags(smic, flags | SMIC_FLAG_BSY);
smic->state = SMIC_READ_NEXT;
} else {
return SI_SM_CALL_WITH_DELAY;
}
break;
case SMIC_READ_NEXT:
switch (status) {
/* smic tells us that this is the last byte to be read
--> clean up */
case SMIC_SC_SMS_RD_END:
read_next_byte(smic);
write_smic_control(smic, SMIC_CC_SMS_RD_END);
write_smic_flags(smic, flags | SMIC_FLAG_BSY);
smic->state = SMIC_READ_END;
break;
case SMIC_SC_SMS_RD_NEXT:
if (flags & SMIC_RX_DATA_READY) {
read_next_byte(smic);
write_smic_control(smic, SMIC_CC_SMS_RD_NEXT);
write_smic_flags(smic, flags | SMIC_FLAG_BSY);
smic->state = SMIC_READ_NEXT;
} else {
return SI_SM_CALL_WITH_DELAY;
}
break;
default:
start_error_recovery(
smic,
"state = SMIC_READ_NEXT, "
"status != SMIC_SC_SMS_RD_(NEXT|END)");
return SI_SM_CALL_WITH_DELAY;
}
break;
case SMIC_READ_END:
if (status != SMIC_SC_SMS_READY) {
start_error_recovery(smic,
"state = SMIC_READ_END, "
"status != SMIC_SC_SMS_READY");
return SI_SM_CALL_WITH_DELAY;
}
data = read_smic_data(smic);
/* data register holds an error code */
if (data != 0) {
if (smic_debug & SMIC_DEBUG_ENABLE) {
printk(KERN_INFO
"SMIC_READ_END: data = %02x\n", data);
}
start_error_recovery(smic,
"state = SMIC_READ_END, "
"data != SUCCESS");
return SI_SM_CALL_WITH_DELAY;
} else {
smic->state = SMIC_IDLE;
return SI_SM_TRANSACTION_COMPLETE;
}
case SMIC_HOSED:
init_smic_data(smic, smic->io);
return SI_SM_HOSED;
default:
if (smic_debug & SMIC_DEBUG_ENABLE) {
printk(KERN_WARNING "smic->state = %d\n", smic->state);
start_error_recovery(smic, "state = UNKNOWN");
return SI_SM_CALL_WITH_DELAY;
}
}
smic->smic_timeout = SMIC_RETRY_TIMEOUT;
return SI_SM_CALL_WITHOUT_DELAY;
}
static int smic_detect(struct si_sm_data *smic)
{
/* It's impossible for the SMIC fnags register to be all 1's,
(assuming a properly functioning, self-initialized BMC)
but that's what you get from reading a bogus address, so we
test that first. */
if (read_smic_flags(smic) == 0xff)
return 1;
return 0;
}
static void smic_cleanup(struct si_sm_data *kcs)
{
}
static int smic_size(void)
{
return sizeof(struct si_sm_data);
}
struct si_sm_handlers smic_smi_handlers =
{
.init_data = init_smic_data,
.start_transaction = start_smic_transaction,
.get_result = smic_get_result,
.event = smic_event,
.detect = smic_detect,
.cleanup = smic_cleanup,
.size = smic_size,
};
