diff options
Diffstat (limited to 'drivers/char/ipmi/ipmi_bt_sm.c')
| -rw-r--r-- | drivers/char/ipmi/ipmi_bt_sm.c | 705 |
1 files changed, 705 insertions, 0 deletions
diff --git a/drivers/char/ipmi/ipmi_bt_sm.c b/drivers/char/ipmi/ipmi_bt_sm.c new file mode 100644 index 000000000..61e716166 --- /dev/null +++ b/drivers/char/ipmi/ipmi_bt_sm.c @@ -0,0 +1,705 @@ +/* + * ipmi_bt_sm.c + * + * The state machine for an Open IPMI BT sub-driver under ipmi_si.c, part + * of the driver architecture at http://sourceforge.net/projects/openipmi + * + * Author: Rocky Craig <first.last@hp.com> + * + * 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/module.h> +#include <linux/moduleparam.h> +#include <linux/ipmi_msgdefs.h> /* for completion codes */ +#include "ipmi_si_sm.h" + +#define BT_DEBUG_OFF 0 /* Used in production */ +#define BT_DEBUG_ENABLE 1 /* Generic messages */ +#define BT_DEBUG_MSG 2 /* Prints all request/response buffers */ +#define BT_DEBUG_STATES 4 /* Verbose look at state changes */ +/* + * BT_DEBUG_OFF must be zero to correspond to the default uninitialized + * value + */ + +static int bt_debug; /* 0 == BT_DEBUG_OFF */ + +module_param(bt_debug, int, 0644); +MODULE_PARM_DESC(bt_debug, "debug bitmask, 1=enable, 2=messages, 4=states"); + +/* + * Typical "Get BT Capabilities" values are 2-3 retries, 5-10 seconds, + * and 64 byte buffers. However, one HP implementation wants 255 bytes of + * buffer (with a documented message of 160 bytes) so go for the max. + * Since the Open IPMI architecture is single-message oriented at this + * stage, the queue depth of BT is of no concern. + */ + +#define BT_NORMAL_TIMEOUT 5 /* seconds */ +#define BT_NORMAL_RETRY_LIMIT 2 +#define BT_RESET_DELAY 6 /* seconds after warm reset */ + +/* + * States are written in chronological order and usually cover + * multiple rows of the state table discussion in the IPMI spec. + */ + +enum bt_states { + BT_STATE_IDLE = 0, /* Order is critical in this list */ + BT_STATE_XACTION_START, + BT_STATE_WRITE_BYTES, + BT_STATE_WRITE_CONSUME, + BT_STATE_READ_WAIT, + BT_STATE_CLEAR_B2H, + BT_STATE_READ_BYTES, + BT_STATE_RESET1, /* These must come last */ + BT_STATE_RESET2, + BT_STATE_RESET3, + BT_STATE_RESTART, + BT_STATE_PRINTME, + BT_STATE_CAPABILITIES_BEGIN, + BT_STATE_CAPABILITIES_END, + BT_STATE_LONG_BUSY /* BT doesn't get hosed :-) */ +}; + +/* + * Macros seen at the end of state "case" blocks. They help with legibility + * and debugging. + */ + +#define BT_STATE_CHANGE(X, Y) { bt->state = X; return Y; } + +#define BT_SI_SM_RETURN(Y) { last_printed = BT_STATE_PRINTME; return Y; } + +struct si_sm_data { + enum bt_states state; + unsigned char seq; /* BT sequence number */ + struct si_sm_io *io; + unsigned char write_data[IPMI_MAX_MSG_LENGTH + 2]; /* +2 for memcpy */ + int write_count; + unsigned char read_data[IPMI_MAX_MSG_LENGTH + 2]; /* +2 for memcpy */ + int read_count; + int truncated; + long timeout; /* microseconds countdown */ + int error_retries; /* end of "common" fields */ + int nonzero_status; /* hung BMCs stay all 0 */ + enum bt_states complete; /* to divert the state machine */ + int BT_CAP_outreqs; + long BT_CAP_req2rsp; + int BT_CAP_retries; /* Recommended retries */ +}; + +#define BT_CLR_WR_PTR 0x01 /* See IPMI 1.5 table 11.6.4 */ +#define BT_CLR_RD_PTR 0x02 +#define BT_H2B_ATN 0x04 +#define BT_B2H_ATN 0x08 +#define BT_SMS_ATN 0x10 +#define BT_OEM0 0x20 +#define BT_H_BUSY 0x40 +#define BT_B_BUSY 0x80 + +/* + * Some bits are toggled on each write: write once to set it, once + * more to clear it; writing a zero does nothing. To absolutely + * clear it, check its state and write if set. This avoids the "get + * current then use as mask" scheme to modify one bit. Note that the + * variable "bt" is hardcoded into these macros. + */ + +#define BT_STATUS bt->io->inputb(bt->io, 0) +#define BT_CONTROL(x) bt->io->outputb(bt->io, 0, x) + +#define BMC2HOST bt->io->inputb(bt->io, 1) +#define HOST2BMC(x) bt->io->outputb(bt->io, 1, x) + +#define BT_INTMASK_R bt->io->inputb(bt->io, 2) +#define BT_INTMASK_W(x) bt->io->outputb(bt->io, 2, x) + +/* + * Convenience routines for debugging. These are not multi-open safe! + * Note the macros have hardcoded variables in them. + */ + +static char *state2txt(unsigned char state) +{ + switch (state) { + case BT_STATE_IDLE: return("IDLE"); + case BT_STATE_XACTION_START: return("XACTION"); + case BT_STATE_WRITE_BYTES: return("WR_BYTES"); + case BT_STATE_WRITE_CONSUME: return("WR_CONSUME"); + case BT_STATE_READ_WAIT: return("RD_WAIT"); + case BT_STATE_CLEAR_B2H: return("CLEAR_B2H"); + case BT_STATE_READ_BYTES: return("RD_BYTES"); + case BT_STATE_RESET1: return("RESET1"); + case BT_STATE_RESET2: return("RESET2"); + case BT_STATE_RESET3: return("RESET3"); + case BT_STATE_RESTART: return("RESTART"); + case BT_STATE_LONG_BUSY: return("LONG_BUSY"); + case BT_STATE_CAPABILITIES_BEGIN: return("CAP_BEGIN"); + case BT_STATE_CAPABILITIES_END: return("CAP_END"); + } + return("BAD STATE"); +} +#define STATE2TXT state2txt(bt->state) + +static char *status2txt(unsigned char status) +{ + /* + * This cannot be called by two threads at the same time and + * the buffer is always consumed immediately, so the static is + * safe to use. + */ + static char buf[40]; + + strcpy(buf, "[ "); + if (status & BT_B_BUSY) + strcat(buf, "B_BUSY "); + if (status & BT_H_BUSY) + strcat(buf, "H_BUSY "); + if (status & BT_OEM0) + strcat(buf, "OEM0 "); + if (status & BT_SMS_ATN) + strcat(buf, "SMS "); + if (status & BT_B2H_ATN) + strcat(buf, "B2H "); + if (status & BT_H2B_ATN) + strcat(buf, "H2B "); + strcat(buf, "]"); + return buf; +} +#define STATUS2TXT status2txt(status) + +/* called externally at insmod time, and internally on cleanup */ + +static unsigned int bt_init_data(struct si_sm_data *bt, struct si_sm_io *io) +{ + memset(bt, 0, sizeof(struct si_sm_data)); + if (bt->io != io) { + /* external: one-time only things */ + bt->io = io; + bt->seq = 0; + } + bt->state = BT_STATE_IDLE; /* start here */ + bt->complete = BT_STATE_IDLE; /* end here */ + bt->BT_CAP_req2rsp = BT_NORMAL_TIMEOUT * USEC_PER_SEC; + bt->BT_CAP_retries = BT_NORMAL_RETRY_LIMIT; + /* BT_CAP_outreqs == zero is a flag to read BT Capabilities */ + return 3; /* We claim 3 bytes of space; ought to check SPMI table */ +} + +/* Jam a completion code (probably an error) into a response */ + +static void force_result(struct si_sm_data *bt, unsigned char completion_code) +{ + bt->read_data[0] = 4; /* # following bytes */ + bt->read_data[1] = bt->write_data[1] | 4; /* Odd NetFn/LUN */ + bt->read_data[2] = bt->write_data[2]; /* seq (ignored) */ + bt->read_data[3] = bt->write_data[3]; /* Command */ + bt->read_data[4] = completion_code; + bt->read_count = 5; +} + +/* The upper state machine starts here */ + +static int bt_start_transaction(struct si_sm_data *bt, + unsigned char *data, + unsigned int size) +{ + unsigned int i; + + if (size < 2) + return IPMI_REQ_LEN_INVALID_ERR; + if (size > IPMI_MAX_MSG_LENGTH) + return IPMI_REQ_LEN_EXCEEDED_ERR; + + if (bt->state == BT_STATE_LONG_BUSY) + return IPMI_NODE_BUSY_ERR; + + if (bt->state != BT_STATE_IDLE) + return IPMI_NOT_IN_MY_STATE_ERR; + + if (bt_debug & BT_DEBUG_MSG) { + printk(KERN_WARNING "BT: +++++++++++++++++ New command\n"); + printk(KERN_WARNING "BT: NetFn/LUN CMD [%d data]:", size - 2); + for (i = 0; i < size; i ++) + printk(" %02x", data[i]); + printk("\n"); + } + bt->write_data[0] = size + 1; /* all data plus seq byte */ + bt->write_data[1] = *data; /* NetFn/LUN */ + bt->write_data[2] = bt->seq++; + memcpy(bt->write_data + 3, data + 1, size - 1); + bt->write_count = size + 2; + bt->error_retries = 0; + bt->nonzero_status = 0; + bt->truncated = 0; + bt->state = BT_STATE_XACTION_START; + bt->timeout = bt->BT_CAP_req2rsp; + force_result(bt, IPMI_ERR_UNSPECIFIED); + return 0; +} + +/* + * After the upper state machine has been told SI_SM_TRANSACTION_COMPLETE + * it calls this. Strip out the length and seq bytes. + */ + +static int bt_get_result(struct si_sm_data *bt, + unsigned char *data, + unsigned int length) +{ + int i, msg_len; + + msg_len = bt->read_count - 2; /* account for length & seq */ + if (msg_len < 3 || msg_len > IPMI_MAX_MSG_LENGTH) { + force_result(bt, IPMI_ERR_UNSPECIFIED); + msg_len = 3; + } + data[0] = bt->read_data[1]; + data[1] = bt->read_data[3]; + if (length < msg_len || bt->truncated) { + data[2] = IPMI_ERR_MSG_TRUNCATED; + msg_len = 3; + } else + memcpy(data + 2, bt->read_data + 4, msg_len - 2); + + if (bt_debug & BT_DEBUG_MSG) { + printk(KERN_WARNING "BT: result %d bytes:", msg_len); + for (i = 0; i < msg_len; i++) + printk(" %02x", data[i]); + printk("\n"); + } + return msg_len; +} + +/* This bit's functionality is optional */ +#define BT_BMC_HWRST 0x80 + +static void reset_flags(struct si_sm_data *bt) +{ + if (bt_debug) + printk(KERN_WARNING "IPMI BT: flag reset %s\n", + status2txt(BT_STATUS)); + if (BT_STATUS & BT_H_BUSY) + BT_CONTROL(BT_H_BUSY); /* force clear */ + BT_CONTROL(BT_CLR_WR_PTR); /* always reset */ + BT_CONTROL(BT_SMS_ATN); /* always clear */ + BT_INTMASK_W(BT_BMC_HWRST); +} + +/* + * Get rid of an unwanted/stale response. This should only be needed for + * BMCs that support multiple outstanding requests. + */ + +static void drain_BMC2HOST(struct si_sm_data *bt) +{ + int i, size; + + if (!(BT_STATUS & BT_B2H_ATN)) /* Not signalling a response */ + return; + + BT_CONTROL(BT_H_BUSY); /* now set */ + BT_CONTROL(BT_B2H_ATN); /* always clear */ + BT_STATUS; /* pause */ + BT_CONTROL(BT_B2H_ATN); /* some BMCs are stubborn */ + BT_CONTROL(BT_CLR_RD_PTR); /* always reset */ + if (bt_debug) + printk(KERN_WARNING "IPMI BT: stale response %s; ", + status2txt(BT_STATUS)); + size = BMC2HOST; + for (i = 0; i < size ; i++) + BMC2HOST; + BT_CONTROL(BT_H_BUSY); /* now clear */ + if (bt_debug) + printk("drained %d bytes\n", size + 1); +} + +static inline void write_all_bytes(struct si_sm_data *bt) +{ + int i; + + if (bt_debug & BT_DEBUG_MSG) { + printk(KERN_WARNING "BT: write %d bytes seq=0x%02X", + bt->write_count, bt->seq); + for (i = 0; i < bt->write_count; i++) + printk(" %02x", bt->write_data[i]); + printk("\n"); + } + for (i = 0; i < bt->write_count; i++) + HOST2BMC(bt->write_data[i]); +} + +static inline int read_all_bytes(struct si_sm_data *bt) +{ + unsigned int i; + + /* + * length is "framing info", minimum = 4: NetFn, Seq, Cmd, cCode. + * Keep layout of first four bytes aligned with write_data[] + */ + + bt->read_data[0] = BMC2HOST; + bt->read_count = bt->read_data[0]; + + if (bt->read_count < 4 || bt->read_count >= IPMI_MAX_MSG_LENGTH) { + if (bt_debug & BT_DEBUG_MSG) + printk(KERN_WARNING "BT: bad raw rsp len=%d\n", + bt->read_count); + bt->truncated = 1; + return 1; /* let next XACTION START clean it up */ + } + for (i = 1; i <= bt->read_count; i++) + bt->read_data[i] = BMC2HOST; + bt->read_count++; /* Account internally for length byte */ + + if (bt_debug & BT_DEBUG_MSG) { + int max = bt->read_count; + + printk(KERN_WARNING "BT: got %d bytes seq=0x%02X", + max, bt->read_data[2]); + if (max > 16) + max = 16; + for (i = 0; i < max; i++) + printk(KERN_CONT " %02x", bt->read_data[i]); + printk(KERN_CONT "%s\n", bt->read_count == max ? "" : " ..."); + } + + /* per the spec, the (NetFn[1], Seq[2], Cmd[3]) tuples must match */ + if ((bt->read_data[3] == bt->write_data[3]) && + (bt->read_data[2] == bt->write_data[2]) && + ((bt->read_data[1] & 0xF8) == (bt->write_data[1] & 0xF8))) + return 1; + + if (bt_debug & BT_DEBUG_MSG) + printk(KERN_WARNING "IPMI BT: bad packet: " + "want 0x(%02X, %02X, %02X) got (%02X, %02X, %02X)\n", + bt->write_data[1] | 0x04, bt->write_data[2], bt->write_data[3], + bt->read_data[1], bt->read_data[2], bt->read_data[3]); + return 0; +} + +/* Restart if retries are left, or return an error completion code */ + +static enum si_sm_result error_recovery(struct si_sm_data *bt, + unsigned char status, + unsigned char cCode) +{ + char *reason; + + bt->timeout = bt->BT_CAP_req2rsp; + + switch (cCode) { + case IPMI_TIMEOUT_ERR: + reason = "timeout"; + break; + default: + reason = "internal error"; + break; + } + + printk(KERN_WARNING "IPMI BT: %s in %s %s ", /* open-ended line */ + reason, STATE2TXT, STATUS2TXT); + + /* + * Per the IPMI spec, retries are based on the sequence number + * known only to this module, so manage a restart here. + */ + (bt->error_retries)++; + if (bt->error_retries < bt->BT_CAP_retries) { + printk("%d retries left\n", + bt->BT_CAP_retries - bt->error_retries); + bt->state = BT_STATE_RESTART; + return SI_SM_CALL_WITHOUT_DELAY; + } + + printk(KERN_WARNING "failed %d retries, sending error response\n", + bt->BT_CAP_retries); + if (!bt->nonzero_status) + printk(KERN_ERR "IPMI BT: stuck, try power cycle\n"); + + /* this is most likely during insmod */ + else if (bt->seq <= (unsigned char)(bt->BT_CAP_retries & 0xFF)) { + printk(KERN_WARNING "IPMI: BT reset (takes 5 secs)\n"); + bt->state = BT_STATE_RESET1; + return SI_SM_CALL_WITHOUT_DELAY; + } + + /* + * Concoct a useful error message, set up the next state, and + * be done with this sequence. + */ + + bt->state = BT_STATE_IDLE; + switch (cCode) { + case IPMI_TIMEOUT_ERR: + if (status & BT_B_BUSY) { + cCode = IPMI_NODE_BUSY_ERR; + bt->state = BT_STATE_LONG_BUSY; + } + break; + default: + break; + } + force_result(bt, cCode); + return SI_SM_TRANSACTION_COMPLETE; +} + +/* Check status and (usually) take action and change this state machine. */ + +static enum si_sm_result bt_event(struct si_sm_data *bt, long time) +{ + unsigned char status, BT_CAP[8]; + static enum bt_states last_printed = BT_STATE_PRINTME; + int i; + + status = BT_STATUS; + bt->nonzero_status |= status; + if ((bt_debug & BT_DEBUG_STATES) && (bt->state != last_printed)) { + printk(KERN_WARNING "BT: %s %s TO=%ld - %ld \n", + STATE2TXT, + STATUS2TXT, + bt->timeout, + time); + last_printed = bt->state; + } + + /* + * Commands that time out may still (eventually) provide a response. + * This stale response will get in the way of a new response so remove + * it if possible (hopefully during IDLE). Even if it comes up later + * it will be rejected by its (now-forgotten) seq number. + */ + + if ((bt->state < BT_STATE_WRITE_BYTES) && (status & BT_B2H_ATN)) { + drain_BMC2HOST(bt); + BT_SI_SM_RETURN(SI_SM_CALL_WITH_DELAY); + } + + if ((bt->state != BT_STATE_IDLE) && + (bt->state < BT_STATE_PRINTME)) { + /* check timeout */ + bt->timeout -= time; + if ((bt->timeout < 0) && (bt->state < BT_STATE_RESET1)) + return error_recovery(bt, + status, + IPMI_TIMEOUT_ERR); + } + + switch (bt->state) { + + /* + * Idle state first checks for asynchronous messages from another + * channel, then does some opportunistic housekeeping. + */ + + case BT_STATE_IDLE: + if (status & BT_SMS_ATN) { + BT_CONTROL(BT_SMS_ATN); /* clear it */ + return SI_SM_ATTN; + } + + if (status & BT_H_BUSY) /* clear a leftover H_BUSY */ + BT_CONTROL(BT_H_BUSY); + + /* Read BT capabilities if it hasn't been done yet */ + if (!bt->BT_CAP_outreqs) + BT_STATE_CHANGE(BT_STATE_CAPABILITIES_BEGIN, + SI_SM_CALL_WITHOUT_DELAY); + bt->timeout = bt->BT_CAP_req2rsp; + BT_SI_SM_RETURN(SI_SM_IDLE); + + case BT_STATE_XACTION_START: + if (status & (BT_B_BUSY | BT_H2B_ATN)) + BT_SI_SM_RETURN(SI_SM_CALL_WITH_DELAY); + if (BT_STATUS & BT_H_BUSY) + BT_CONTROL(BT_H_BUSY); /* force clear */ + BT_STATE_CHANGE(BT_STATE_WRITE_BYTES, + SI_SM_CALL_WITHOUT_DELAY); + + case BT_STATE_WRITE_BYTES: + if (status & BT_H_BUSY) + BT_CONTROL(BT_H_BUSY); /* clear */ + BT_CONTROL(BT_CLR_WR_PTR); + write_all_bytes(bt); + BT_CONTROL(BT_H2B_ATN); /* can clear too fast to catch */ + BT_STATE_CHANGE(BT_STATE_WRITE_CONSUME, + SI_SM_CALL_WITHOUT_DELAY); + + case BT_STATE_WRITE_CONSUME: + if (status & (BT_B_BUSY | BT_H2B_ATN)) + BT_SI_SM_RETURN(SI_SM_CALL_WITH_DELAY); + BT_STATE_CHANGE(BT_STATE_READ_WAIT, + SI_SM_CALL_WITHOUT_DELAY); + + /* Spinning hard can suppress B2H_ATN and force a timeout */ + + case BT_STATE_READ_WAIT: + if (!(status & BT_B2H_ATN)) + BT_SI_SM_RETURN(SI_SM_CALL_WITH_DELAY); + BT_CONTROL(BT_H_BUSY); /* set */ + + /* + * Uncached, ordered writes should just proceed serially but + * some BMCs don't clear B2H_ATN with one hit. Fast-path a + * workaround without too much penalty to the general case. + */ + + BT_CONTROL(BT_B2H_ATN); /* clear it to ACK the BMC */ + BT_STATE_CHANGE(BT_STATE_CLEAR_B2H, + SI_SM_CALL_WITHOUT_DELAY); + + case BT_STATE_CLEAR_B2H: + if (status & BT_B2H_ATN) { + /* keep hitting it */ + BT_CONTROL(BT_B2H_ATN); + BT_SI_SM_RETURN(SI_SM_CALL_WITH_DELAY); + } + BT_STATE_CHANGE(BT_STATE_READ_BYTES, + SI_SM_CALL_WITHOUT_DELAY); + + case BT_STATE_READ_BYTES: + if (!(status & BT_H_BUSY)) + /* check in case of retry */ + BT_CONTROL(BT_H_BUSY); + BT_CONTROL(BT_CLR_RD_PTR); /* start of BMC2HOST buffer */ + i = read_all_bytes(bt); /* true == packet seq match */ + BT_CONTROL(BT_H_BUSY); /* NOW clear */ + if (!i) /* Not my message */ + BT_STATE_CHANGE(BT_STATE_READ_WAIT, + SI_SM_CALL_WITHOUT_DELAY); + bt->state = bt->complete; + return bt->state == BT_STATE_IDLE ? /* where to next? */ + SI_SM_TRANSACTION_COMPLETE : /* normal */ + SI_SM_CALL_WITHOUT_DELAY; /* Startup magic */ + + case BT_STATE_LONG_BUSY: /* For example: after FW update */ + if (!(status & BT_B_BUSY)) { + reset_flags(bt); /* next state is now IDLE */ + bt_init_data(bt, bt->io); + } + return SI_SM_CALL_WITH_DELAY; /* No repeat printing */ + + case BT_STATE_RESET1: + reset_flags(bt); + drain_BMC2HOST(bt); + BT_STATE_CHANGE(BT_STATE_RESET2, + SI_SM_CALL_WITH_DELAY); + + case BT_STATE_RESET2: /* Send a soft reset */ + BT_CONTROL(BT_CLR_WR_PTR); + HOST2BMC(3); /* number of bytes following */ + HOST2BMC(0x18); /* NetFn/LUN == Application, LUN 0 */ + HOST2BMC(42); /* Sequence number */ + HOST2BMC(3); /* Cmd == Soft reset */ + BT_CONTROL(BT_H2B_ATN); + bt->timeout = BT_RESET_DELAY * USEC_PER_SEC; + BT_STATE_CHANGE(BT_STATE_RESET3, + SI_SM_CALL_WITH_DELAY); + + case BT_STATE_RESET3: /* Hold off everything for a bit */ + if (bt->timeout > 0) + return SI_SM_CALL_WITH_DELAY; + drain_BMC2HOST(bt); + BT_STATE_CHANGE(BT_STATE_RESTART, + SI_SM_CALL_WITH_DELAY); + + case BT_STATE_RESTART: /* don't reset retries or seq! */ + bt->read_count = 0; + bt->nonzero_status = 0; + bt->timeout = bt->BT_CAP_req2rsp; + BT_STATE_CHANGE(BT_STATE_XACTION_START, + SI_SM_CALL_WITH_DELAY); + + /* + * Get BT Capabilities, using timing of upper level state machine. + * Set outreqs to prevent infinite loop on timeout. + */ + case BT_STATE_CAPABILITIES_BEGIN: + bt->BT_CAP_outreqs = 1; + { + unsigned char GetBT_CAP[] = { 0x18, 0x36 }; + bt->state = BT_STATE_IDLE; + bt_start_transaction(bt, GetBT_CAP, sizeof(GetBT_CAP)); + } + bt->complete = BT_STATE_CAPABILITIES_END; + BT_STATE_CHANGE(BT_STATE_XACTION_START, + SI_SM_CALL_WITH_DELAY); + + case BT_STATE_CAPABILITIES_END: + i = bt_get_result(bt, BT_CAP, sizeof(BT_CAP)); + bt_init_data(bt, bt->io); + if ((i == 8) && !BT_CAP[2]) { + bt->BT_CAP_outreqs = BT_CAP[3]; + bt->BT_CAP_req2rsp = BT_CAP[6] * USEC_PER_SEC; + bt->BT_CAP_retries = BT_CAP[7]; + } else + printk(KERN_WARNING "IPMI BT: using default values\n"); + if (!bt->BT_CAP_outreqs) + bt->BT_CAP_outreqs = 1; + printk(KERN_WARNING "IPMI BT: req2rsp=%ld secs retries=%d\n", + bt->BT_CAP_req2rsp / USEC_PER_SEC, bt->BT_CAP_retries); + bt->timeout = bt->BT_CAP_req2rsp; + return SI_SM_CALL_WITHOUT_DELAY; + + default: /* should never occur */ + return error_recovery(bt, + status, + IPMI_ERR_UNSPECIFIED); + } + return SI_SM_CALL_WITH_DELAY; +} + +static int bt_detect(struct si_sm_data *bt) +{ + /* + * It's impossible for the BT status and interrupt registers 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. The calling routine uses negative logic. + */ + + if ((BT_STATUS == 0xFF) && (BT_INTMASK_R == 0xFF)) + return 1; + reset_flags(bt); + return 0; +} + +static void bt_cleanup(struct si_sm_data *bt) +{ +} + +static int bt_size(void) +{ + return sizeof(struct si_sm_data); +} + +struct si_sm_handlers bt_smi_handlers = { + .init_data = bt_init_data, + .start_transaction = bt_start_transaction, + .get_result = bt_get_result, + .event = bt_event, + .detect = bt_detect, + .cleanup = bt_cleanup, + .size = bt_size, +}; |