ipmi_si_intf.c

linux-2.6.15.6

/*
 * ipmi_si.c
 *
 * The interface to the IPMI driver for the system interfaces (KCS, SMIC,
 * BT).
 *
 * Author: MontaVista Software, Inc.
 *         Corey Minyard <[e-mail]>
 *         [e-mail]
 *
 * Copyright 2002 MontaVista Software Inc.
 *
 *  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.
 */

/*
 * This file holds the "policy" for the interface to the SMI state
 * machine.  It does the configuration, handles timers and interrupts,
 * and drives the real SMI state machine.
 */

#include <linux/config.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <asm/system.h>
#include <linux/sched.h>
#include <linux/timer.h>
#include <linux/errno.h>
#include <linux/spinlock.h>
#include <linux/slab.h>
#include <linux/delay.h>
#include <linux/list.h>
#include <linux/pci.h>
#include <linux/ioport.h>
#include <linux/notifier.h>
#include <linux/kthread.h>
#include <asm/irq.h>
#ifdef CONFIG_HIGH_RES_TIMERS
#include <linux/hrtime.h>
# if defined(schedule_next_int)
/* Old high-res timer code, do translations. */
#  define get_arch_cycles(a) quick_update_jiffies_sub(a)
#  define arch_cycles_per_jiffy cycles_per_jiffies
# endif
static inline void add_usec_to_timer(struct timer_list *t, long v)
{
	t->arch_cycle_expires += nsec_to_arch_cycle(v * 1000);
	while (t->arch_cycle_expires >= arch_cycles_per_jiffy)
	{
		t->expires++;
		t->arch_cycle_expires -= arch_cycles_per_jiffy;
	}
}
#endif
#include <linux/interrupt.h>
#include <linux/rcupdate.h>
#include <linux/ipmi_smi.h>
#include <asm/io.h>
#include "ipmi_si_sm.h"
#include <linux/init.h>
#include <linux/dmi.h>

/* Measure times between events in the driver. */
#undef DEBUG_TIMING

/* Call every 10 ms. */
#define SI_TIMEOUT_TIME_USEC	10000
#define SI_USEC_PER_JIFFY	(1000000/HZ)
#define SI_TIMEOUT_JIFFIES	(SI_TIMEOUT_TIME_USEC/SI_USEC_PER_JIFFY)
#define SI_SHORT_TIMEOUT_USEC  250 /* .25ms when the SM request a
                                       short timeout */

enum si_intf_state {
	SI_NORMAL,
	SI_GETTING_FLAGS,
	SI_GETTING_EVENTS,
	SI_CLEARING_FLAGS,
	SI_CLEARING_FLAGS_THEN_SET_IRQ,
	SI_GETTING_MESSAGES,
	SI_ENABLE_INTERRUPTS1,
	SI_ENABLE_INTERRUPTS2
	/* FIXME - add watchdog stuff. */
};

/* Some BT-specific defines we need here. */
#define IPMI_BT_INTMASK_REG		2
#define IPMI_BT_INTMASK_CLEAR_IRQ_BIT	2
#define IPMI_BT_INTMASK_ENABLE_IRQ_BIT	1

enum si_type {
    SI_KCS, SI_SMIC, SI_BT
};

struct ipmi_device_id {
	unsigned char device_id;
	unsigned char device_revision;
	unsigned char firmware_revision_1;
	unsigned char firmware_revision_2;
	unsigned char ipmi_version;
	unsigned char additional_device_support;
	unsigned char manufacturer_id[3];
	unsigned char product_id[2];
	unsigned char aux_firmware_revision[4];
} __attribute__((packed));

#define ipmi_version_major(v) ((v)->ipmi_version & 0xf)
#define ipmi_version_minor(v) ((v)->ipmi_version >> 4)

struct smi_info
{
	int                    intf_num;
	ipmi_smi_t             intf;
	struct si_sm_data      *si_sm;
	struct si_sm_handlers  *handlers;
	enum si_type           si_type;
	spinlock_t             si_lock;
	spinlock_t             msg_lock;
	struct list_head       xmit_msgs;
	struct list_head       hp_xmit_msgs;
	struct ipmi_smi_msg    *curr_msg;
	enum si_intf_state     si_state;

	/* Used to handle the various types of I/O that can occur with
           IPMI */
	struct si_sm_io io;
	int (*io_setup)(struct smi_info *info);
	void (*io_cleanup)(struct smi_info *info);
	int (*irq_setup)(struct smi_info *info);
	void (*irq_cleanup)(struct smi_info *info);
	unsigned int io_size;

	/* Per-OEM handler, called from handle_flags().
	   Returns 1 when handle_flags() needs to be re-run
	   or 0 indicating it set si_state itself.
	*/
	int (*oem_data_avail_handler)(struct smi_info *smi_info);

	/* Flags from the last GET_MSG_FLAGS command, used when an ATTN
	   is set to hold the flags until we are done handling everything
	   from the flags. */
#define RECEIVE_MSG_AVAIL	0x01
#define EVENT_MSG_BUFFER_FULL	0x02
#define WDT_PRE_TIMEOUT_INT	0x08
#define OEM0_DATA_AVAIL     0x20
#define OEM1_DATA_AVAIL     0x40
#define OEM2_DATA_AVAIL     0x80
#define OEM_DATA_AVAIL      (OEM0_DATA_AVAIL | \
                             OEM1_DATA_AVAIL | \
                             OEM2_DATA_AVAIL)
	unsigned char       msg_flags;

	/* If set to true, this will request events the next time the
	   state machine is idle. */
	atomic_t            req_events;

	/* If true, run the state machine to completion on every send
	   call.  Generally used after a panic to make sure stuff goes
	   out. */
	int                 run_to_completion;

	/* The I/O port of an SI interface. */
	int                 port;

	/* The space between start addresses of the two ports.  For
	   instance, if the first port is 0xca2 and the spacing is 4, then
	   the second port is 0xca6. */
	unsigned int        spacing;

	/* zero if no irq; */
	int                 irq;

	/* The timer for this si. */
	struct timer_list   si_timer;

	/* The time (in jiffies) the last timeout occurred at. */
	unsigned long       last_timeout_jiffies;

	/* Used to gracefully stop the timer without race conditions. */
	atomic_t            stop_operation;

	/* The driver will disable interrupts when it gets into a
	   situation where it cannot handle messages due to lack of
	   memory.  Once that situation clears up, it will re-enable
	   interrupts. */
	int interrupt_disabled;

	struct ipmi_device_id device_id;

	/* Slave address, could be reported from DMI. */
	unsigned char slave_addr;

	/* Counters and things for the proc filesystem. */
	spinlock_t count_lock;
	unsigned long short_timeouts;
	unsigned long long_timeouts;
	unsigned long timeout_restarts;
	unsigned long idles;
	unsigned long interrupts;
	unsigned long attentions;
	unsigned long flag_fetches;
	unsigned long hosed_count;
	unsigned long complete_transactions;
	unsigned long events;
	unsigned long watchdog_pretimeouts;
	unsigned long incoming_messages;

        struct task_struct *thread;
};

static struct notifier_block *xaction_notifier_list;
static int register_xaction_notifier(struct notifier_block * nb)
{
	return notifier_chain_register(&xaction_notifier_list, nb);
}

static void si_restart_short_timer(struct smi_info *smi_info);

static void deliver_recv_msg(struct smi_info *smi_info,
			     struct ipmi_smi_msg *msg)
{
	/* Deliver the message to the upper layer with the lock
           released. */
	spin_unlock(&(smi_info->si_lock));
	ipmi_smi_msg_received(smi_info->intf, msg);
	spin_lock(&(smi_info->si_lock));
}

static void return_hosed_msg(struct smi_info *smi_info)
{
	struct ipmi_smi_msg *msg = smi_info->curr_msg;

	/* Make it a reponse */
	msg->rsp[0] = msg->data[0] | 4;
	msg->rsp[1] = msg->data[1];
	msg->rsp[2] = 0xFF; /* Unknown error. */
	msg->rsp_size = 3;

	smi_info->curr_msg = NULL;
	deliver_recv_msg(smi_info, msg);
}

static enum si_sm_result start_next_msg(struct smi_info *smi_info)
{
	int              rv;
	struct list_head *entry = NULL;
#ifdef DEBUG_TIMING
	struct timeval t;
#endif

	/* No need to save flags, we aleady have interrupts off and we
	   already hold the SMI lock. */
	spin_lock(&(smi_info->msg_lock));

	/* Pick the high priority queue first. */
	if (! list_empty(&(smi_info->hp_xmit_msgs))) {
		entry = smi_info->hp_xmit_msgs.next;
	} else if (! list_empty(&(smi_info->xmit_msgs))) {
		entry = smi_info->xmit_msgs.next;
	}

	if (! entry) {
		smi_info->curr_msg = NULL;
		rv = SI_SM_IDLE;
	} else {
		int err;

		list_del(entry);
		smi_info->curr_msg = list_entry(entry,
						struct ipmi_smi_msg,
						link);
#ifdef DEBUG_TIMING
		do_gettimeofday(&t);
		printk("**Start2: %d.%9.9d\n", t.tv_sec, t.tv_usec);
#endif
		err = notifier_call_chain(&xaction_notifier_list, 0, smi_info);
		if (err & NOTIFY_STOP_MASK) {
			rv = SI_SM_CALL_WITHOUT_DELAY;
			goto out;
		}
		err = smi_info->handlers->start_transaction(
			smi_info->si_sm,
			smi_info->curr_msg->data,
			smi_info->curr_msg->data_size);
		if (err) {
			return_hosed_msg(smi_info);
		}

		rv = SI_SM_CALL_WITHOUT_DELAY;
	}
	out:
	spin_unlock(&(smi_info->msg_lock));

	return rv;
}

static void start_enable_irq(struct smi_info *smi_info)
{
	unsigned char msg[2];

	/* If we are enabling interrupts, we have to tell the
	   BMC to use them. */
	msg[0] = (IPMI_NETFN_APP_REQUEST << 2);
	msg[1] = IPMI_GET_BMC_GLOBAL_ENABLES_CMD;

	smi_info->handlers->start_transaction(smi_info->si_sm, msg, 2);
	smi_info->si_state = SI_ENABLE_INTERRUPTS1;
}

static void start_clear_flags(struct smi_info *smi_info)
{
	unsigned char msg[3];

	/* Make sure the watchdog pre-timeout flag is not set at startup. */
	msg[0] = (IPMI_NETFN_APP_REQUEST << 2);
	msg[1] = IPMI_CLEAR_MSG_FLAGS_CMD;
	msg[2] = WDT_PRE_TIMEOUT_INT;

	smi_info->handlers->start_transaction(smi_info->si_sm, msg, 3);
	smi_info->si_state = SI_CLEARING_FLAGS;
}

/* When we have a situtaion where we run out of memory and cannot
   allocate messages, we just leave them in the BMC and run the system
   polled until we can allocate some memory.  Once we have some
   memory, we will re-enable the interrupt. */
static inline void disable_si_irq(struct smi_info *smi_info)
{
	if ((smi_info->irq) && (! smi_info->interrupt_disabled)) {
		disable_irq_nosync(smi_info->irq);
		smi_info->interrupt_disabled = 1;
	}
}

static inline void enable_si_irq(struct smi_info *smi_info)
{
	if ((smi_info->irq) && (smi_info->interrupt_disabled)) {
		enable_irq(smi_info->irq);
		smi_info->interrupt_disabled = 0;
	}
}

static void handle_flags(struct smi_info *smi_info)
{
 retry:
	if (smi_info->msg_flags & WDT_PRE_TIMEOUT_INT) {
		/* Watchdog pre-timeout */
		spin_lock(&smi_info->count_lock);
		smi_info->watchdog_pretimeouts++;
		spin_unlock(&smi_info->count_lock);

		start_clear_flags(smi_info);
		smi_info->msg_flags &= ~WDT_PRE_TIMEOUT_INT;
		spin_unlock(&(smi_info->si_lock));
		ipmi_smi_watchdog_pretimeout(smi_info->intf);
		spin_lock(&(smi_info->si_lock));
	} else if (smi_info->msg_flags & RECEIVE_MSG_AVAIL) {
		/* Messages available. */
		smi_info->curr_msg = ipmi_alloc_smi_msg();
		if (! smi_info->curr_msg) {
			disable_si_irq(smi_info);
			smi_info->si_state = SI_NORMAL;
			return;
		}
		enable_si_irq(smi_info);

		smi_info->curr_msg->data[0] = (IPMI_NETFN_APP_REQUEST << 2);
		smi_info->curr_msg->data[1] = IPMI_GET_MSG_CMD;
		smi_info->curr_msg->data_size = 2;

		smi_info->handlers->start_transaction(
			smi_info->si_sm,
			smi_info->curr_msg->data,
			smi_info->curr_msg->data_size);
		smi_info->si_state = SI_GETTING_MESSAGES;
	} else if (smi_info->msg_flags & EVENT_MSG_BUFFER_FULL) {
		/* Events available. */
		smi_info->curr_msg = ipmi_alloc_smi_msg();
		if (! smi_info->curr_msg) {
			disable_si_irq(smi_info);
			smi_info->si_state = SI_NORMAL;
			return;
		}
		enable_si_irq(smi_info);

		smi_info->curr_msg->data[0] = (IPMI_NETFN_APP_REQUEST << 2);
		smi_info->curr_msg->data[1] = IPMI_READ_EVENT_MSG_BUFFER_CMD;
		smi_info->curr_msg->data_size = 2;

		smi_info->handlers->start_transaction(
			smi_info->si_sm,
			smi_info->curr_msg->data,
			smi_info->curr_msg->data_size);
		smi_info->si_state = SI_GETTING_EVENTS;
	} else if (smi_info->msg_flags & OEM_DATA_AVAIL) {
		if (smi_info->oem_data_avail_handler)
			if (smi_info->oem_data_avail_handler(smi_info))
				goto retry;
	} else {
		smi_info->si_state = SI_NORMAL;
	}
}

static void handle_transaction_done(struct smi_info *smi_info)
{
	struct ipmi_smi_msg *msg;
#ifdef DEBUG_TIMING
	struct timeval t;

	do_gettimeofday(&t);
	printk("**Done: %d.%9.9d\n", t.tv_sec, t.tv_usec);
#endif
	switch (smi_info->si_state) {
	case SI_NORMAL:
		if (! smi_info->curr_msg)
			break;

		smi_info->curr_msg->rsp_size
			= smi_info->handlers->get_result(
				smi_info->si_sm,
				smi_info->curr_msg->rsp,
				IPMI_MAX_MSG_LENGTH);

		/* Do this here becase deliver_recv_msg() releases the
		   lock, and a new message can be put in during the
		   time the lock is released. */
		msg = smi_info->curr_msg;
		smi_info->curr_msg = NULL;
		deliver_recv_msg(smi_info, msg);
		break;

	case SI_GETTING_FLAGS:
	{
		unsigned char msg[4];
		unsigned int  len;

		/* We got the flags from the SMI, now handle them. */
		len = smi_info->handlers->get_result(smi_info->si_sm, msg, 4);
		if (msg[2] != 0) {
			/* Error fetching flags, just give up for
			   now. */
			smi_info->si_state = SI_NORMAL;
		} else if (len < 4) {
			/* Hmm, no flags.  That's technically illegal, but
			   don't use uninitialized data. */
			smi_info->si_state = SI_NORMAL;
		} else {
			smi_info->msg_flags = msg[3];
			handle_flags(smi_info);
		}
		break;
	}

	case SI_CLEARING_FLAGS:
	case SI_CLEARING_FLAGS_THEN_SET_IRQ:
	{
		unsigned char msg[3];

		/* We cleared the flags. */
		smi_info->handlers->get_result(smi_info->si_sm, msg, 3);
		if (msg[2] != 0) {