diff options
Diffstat (limited to '')
| -rw-r--r-- | drivers/char/ipmi/ipmi_si_intf.c | 2307 |
1 files changed, 2307 insertions, 0 deletions
diff --git a/drivers/char/ipmi/ipmi_si_intf.c b/drivers/char/ipmi/ipmi_si_intf.c new file mode 100644 index 000000000..5cd031f3f --- /dev/null +++ b/drivers/char/ipmi/ipmi_si_intf.c @@ -0,0 +1,2307 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * ipmi_si.c + * + * The interface to the IPMI driver for the system interfaces (KCS, SMIC, + * BT). + * + * Author: MontaVista Software, Inc. + * Corey Minyard <minyard@mvista.com> + * source@mvista.com + * + * Copyright 2002 MontaVista Software Inc. + * Copyright 2006 IBM Corp., Christian Krafft <krafft@de.ibm.com> + */ + +/* + * 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. + */ + +#define pr_fmt(fmt) "ipmi_si: " fmt + +#include <linux/module.h> +#include <linux/moduleparam.h> +#include <linux/sched.h> +#include <linux/seq_file.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/notifier.h> +#include <linux/mutex.h> +#include <linux/kthread.h> +#include <asm/irq.h> +#include <linux/interrupt.h> +#include <linux/rcupdate.h> +#include <linux/ipmi.h> +#include <linux/ipmi_smi.h> +#include "ipmi_si.h" +#include "ipmi_si_sm.h" +#include <linux/string.h> +#include <linux/ctype.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_GETTING_MESSAGES, + SI_CHECKING_ENABLES, + SI_SETTING_ENABLES + /* 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 + +/* 'invalid' to allow a firmware-specified interface to be disabled */ +const char *const si_to_str[] = { "invalid", "kcs", "smic", "bt", NULL }; + +static bool initialized; + +/* + * Indexes into stats[] in smi_info below. + */ +enum si_stat_indexes { + /* + * Number of times the driver requested a timer while an operation + * was in progress. + */ + SI_STAT_short_timeouts = 0, + + /* + * Number of times the driver requested a timer while nothing was in + * progress. + */ + SI_STAT_long_timeouts, + + /* Number of times the interface was idle while being polled. */ + SI_STAT_idles, + + /* Number of interrupts the driver handled. */ + SI_STAT_interrupts, + + /* Number of time the driver got an ATTN from the hardware. */ + SI_STAT_attentions, + + /* Number of times the driver requested flags from the hardware. */ + SI_STAT_flag_fetches, + + /* Number of times the hardware didn't follow the state machine. */ + SI_STAT_hosed_count, + + /* Number of completed messages. */ + SI_STAT_complete_transactions, + + /* Number of IPMI events received from the hardware. */ + SI_STAT_events, + + /* Number of watchdog pretimeouts. */ + SI_STAT_watchdog_pretimeouts, + + /* Number of asynchronous messages received. */ + SI_STAT_incoming_messages, + + + /* This *must* remain last, add new values above this. */ + SI_NUM_STATS +}; + +struct smi_info { + int si_num; + struct ipmi_smi *intf; + struct si_sm_data *si_sm; + const struct si_sm_handlers *handlers; + spinlock_t si_lock; + struct ipmi_smi_msg *waiting_msg; + 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; + + /* + * 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; + + /* Does the BMC have an event buffer? */ + bool has_event_buffer; + + /* + * 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. + */ + bool run_to_completion; + + /* The timer for this si. */ + struct timer_list si_timer; + + /* This flag is set, if the timer can be set */ + bool timer_can_start; + + /* This flag is set, if the timer is running (timer_pending() isn't enough) */ + bool timer_running; + + /* The time (in jiffies) the last timeout occurred at. */ + unsigned long last_timeout_jiffies; + + /* Are we waiting for the events, pretimeouts, received msgs? */ + atomic_t need_watch; + + /* + * 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. + */ + bool interrupt_disabled; + + /* + * Does the BMC support events? + */ + bool supports_event_msg_buff; + + /* + * Can we disable interrupts the global enables receive irq + * bit? There are currently two forms of brokenness, some + * systems cannot disable the bit (which is technically within + * the spec but a bad idea) and some systems have the bit + * forced to zero even though interrupts work (which is + * clearly outside the spec). The next bool tells which form + * of brokenness is present. + */ + bool cannot_disable_irq; + + /* + * Some systems are broken and cannot set the irq enable + * bit, even if they support interrupts. + */ + bool irq_enable_broken; + + /* Is the driver in maintenance mode? */ + bool in_maintenance_mode; + + /* + * Did we get an attention that we did not handle? + */ + bool got_attn; + + /* From the get device id response... */ + struct ipmi_device_id device_id; + + /* Have we added the device group to the device? */ + bool dev_group_added; + + /* Counters and things for the proc filesystem. */ + atomic_t stats[SI_NUM_STATS]; + + struct task_struct *thread; + + struct list_head link; +}; + +#define smi_inc_stat(smi, stat) \ + atomic_inc(&(smi)->stats[SI_STAT_ ## stat]) +#define smi_get_stat(smi, stat) \ + ((unsigned int) atomic_read(&(smi)->stats[SI_STAT_ ## stat])) + +#define IPMI_MAX_INTFS 4 +static int force_kipmid[IPMI_MAX_INTFS]; +static int num_force_kipmid; + +static unsigned int kipmid_max_busy_us[IPMI_MAX_INTFS]; +static int num_max_busy_us; + +static bool unload_when_empty = true; + +static int try_smi_init(struct smi_info *smi); +static void cleanup_one_si(struct smi_info *smi_info); +static void cleanup_ipmi_si(void); + +#ifdef DEBUG_TIMING +void debug_timestamp(struct smi_info *smi_info, char *msg) +{ + struct timespec64 t; + + ktime_get_ts64(&t); + dev_dbg(smi_info->io.dev, "**%s: %lld.%9.9ld\n", + msg, t.tv_sec, t.tv_nsec); +} +#else +#define debug_timestamp(smi_info, x) +#endif + +static ATOMIC_NOTIFIER_HEAD(xaction_notifier_list); +static int register_xaction_notifier(struct notifier_block *nb) +{ + return atomic_notifier_chain_register(&xaction_notifier_list, nb); +} + +static void deliver_recv_msg(struct smi_info *smi_info, + struct ipmi_smi_msg *msg) +{ + /* Deliver the message to the upper layer. */ + ipmi_smi_msg_received(smi_info->intf, msg); +} + +static void return_hosed_msg(struct smi_info *smi_info, int cCode) +{ + struct ipmi_smi_msg *msg = smi_info->curr_msg; + + if (cCode < 0 || cCode > IPMI_ERR_UNSPECIFIED) + cCode = IPMI_ERR_UNSPECIFIED; + /* else use it as is */ + + /* Make it a response */ + msg->rsp[0] = msg->data[0] | 4; + msg->rsp[1] = msg->data[1]; + msg->rsp[2] = cCode; + 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; + + if (!smi_info->waiting_msg) { + smi_info->curr_msg = NULL; + rv = SI_SM_IDLE; + } else { + int err; + + smi_info->curr_msg = smi_info->waiting_msg; + smi_info->waiting_msg = NULL; + debug_timestamp(smi_info, "Start2"); + err = atomic_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, err); + + rv = SI_SM_CALL_WITHOUT_DELAY; + } +out: + return rv; +} + +static void smi_mod_timer(struct smi_info *smi_info, unsigned long new_val) +{ + if (!smi_info->timer_can_start) + return; + smi_info->last_timeout_jiffies = jiffies; + mod_timer(&smi_info->si_timer, new_val); + smi_info->timer_running = true; +} + +/* + * Start a new message and (re)start the timer and thread. + */ +static void start_new_msg(struct smi_info *smi_info, unsigned char *msg, + unsigned int size) +{ + smi_mod_timer(smi_info, jiffies + SI_TIMEOUT_JIFFIES); + + if (smi_info->thread) + wake_up_process(smi_info->thread); + + smi_info->handlers->start_transaction(smi_info->si_sm, msg, size); +} + +static void start_check_enables(struct smi_info *smi_info) +{ + unsigned char msg[2]; + + msg[0] = (IPMI_NETFN_APP_REQUEST << 2); + msg[1] = IPMI_GET_BMC_GLOBAL_ENABLES_CMD; + + start_new_msg(smi_info, msg, 2); + smi_info->si_state = SI_CHECKING_ENABLES; +} + +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; + + start_new_msg(smi_info, msg, 3); + smi_info->si_state = SI_CLEARING_FLAGS; +} + +static void start_getting_msg_queue(struct smi_info *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; + + start_new_msg(smi_info, smi_info->curr_msg->data, + smi_info->curr_msg->data_size); + smi_info->si_state = SI_GETTING_MESSAGES; +} + +static void start_getting_events(struct smi_info *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; + + start_new_msg(smi_info, smi_info->curr_msg->data, + smi_info->curr_msg->data_size); + smi_info->si_state = SI_GETTING_EVENTS; +} + +/* + * 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. + * + * Note that we cannot just use disable_irq(), since the interrupt may + * be shared. + */ +static inline bool disable_si_irq(struct smi_info *smi_info) +{ + if ((smi_info->io.irq) && (!smi_info->interrupt_disabled)) { + smi_info->interrupt_disabled = true; + start_check_enables(smi_info); + return true; + } + return false; +} + +static inline bool enable_si_irq(struct smi_info *smi_info) +{ + if ((smi_info->io.irq) && (smi_info->interrupt_disabled)) { + smi_info->interrupt_disabled = false; + start_check_enables(smi_info); + return true; + } + return false; +} + +/* + * Allocate a message. If unable to allocate, start the interrupt + * disable process and return NULL. If able to allocate but + * interrupts are disabled, free the message and return NULL after + * starting the interrupt enable process. + */ +static struct ipmi_smi_msg *alloc_msg_handle_irq(struct smi_info *smi_info) +{ + struct ipmi_smi_msg *msg; + + msg = ipmi_alloc_smi_msg(); + if (!msg) { + if (!disable_si_irq(smi_info)) + smi_info->si_state = SI_NORMAL; + } else if (enable_si_irq(smi_info)) { + ipmi_free_smi_msg(msg); + msg = NULL; + } + return msg; +} + +static void handle_flags(struct smi_info *smi_info) +{ +retry: + if (smi_info->msg_flags & WDT_PRE_TIMEOUT_INT) { + /* Watchdog pre-timeout */ + smi_inc_stat(smi_info, watchdog_pretimeouts); + + start_clear_flags(smi_info); + smi_info->msg_flags &= ~WDT_PRE_TIMEOUT_INT; + ipmi_smi_watchdog_pretimeout(smi_info->intf); + } else if (smi_info->msg_flags & RECEIVE_MSG_AVAIL) { + /* Messages available. */ + smi_info->curr_msg = alloc_msg_handle_irq(smi_info); + if (!smi_info->curr_msg) + return; + + start_getting_msg_queue(smi_info); + } else if (smi_info->msg_flags & EVENT_MSG_BUFFER_FULL) { + /* Events available. */ + smi_info->curr_msg = alloc_msg_handle_irq(smi_info); + if (!smi_info->curr_msg) + return; + + start_getting_events(smi_info); + } else if (smi_info->msg_flags & OEM_DATA_AVAIL && + smi_info->oem_data_avail_handler) { + if (smi_info->oem_data_avail_handler(smi_info)) + goto retry; + } else + smi_info->si_state = SI_NORMAL; +} + +/* + * Global enables we care about. + */ +#define GLOBAL_ENABLES_MASK (IPMI_BMC_EVT_MSG_BUFF | IPMI_BMC_RCV_MSG_INTR | \ + IPMI_BMC_EVT_MSG_INTR) + +static u8 current_global_enables(struct smi_info *smi_info, u8 base, + bool *irq_on) +{ + u8 enables = 0; + + if (smi_info->supports_event_msg_buff) + enables |= IPMI_BMC_EVT_MSG_BUFF; + + if (((smi_info->io.irq && !smi_info->interrupt_disabled) || + smi_info->cannot_disable_irq) && + !smi_info->irq_enable_broken) + enables |= IPMI_BMC_RCV_MSG_INTR; + + if (smi_info->supports_event_msg_buff && + smi_info->io.irq && !smi_info->interrupt_disabled && + !smi_info->irq_enable_broken) + enables |= IPMI_BMC_EVT_MSG_INTR; + + *irq_on = enables & (IPMI_BMC_EVT_MSG_INTR | IPMI_BMC_RCV_MSG_INTR); + + return enables; +} + +static void check_bt_irq(struct smi_info *smi_info, bool irq_on) +{ + u8 irqstate = smi_info->io.inputb(&smi_info->io, IPMI_BT_INTMASK_REG); + + irqstate &= IPMI_BT_INTMASK_ENABLE_IRQ_BIT; + + if ((bool)irqstate == irq_on) + return; + + if (irq_on) + smi_info->io.outputb(&smi_info->io, IPMI_BT_INTMASK_REG, + IPMI_BT_INTMASK_ENABLE_IRQ_BIT); + else + smi_info->io.outputb(&smi_info->io, IPMI_BT_INTMASK_REG, 0); +} + +static void handle_transaction_done(struct smi_info *smi_info) +{ + struct ipmi_smi_msg *msg; + + debug_timestamp(smi_info, "Done"); + 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: + { + unsigned char msg[3]; + + /* We cleared the flags. */ + smi_info->handlers->get_result(smi_info->si_sm, msg, 3); + if (msg[2] != 0) { + /* Error clearing flags */ + dev_warn_ratelimited(smi_info->io.dev, + "Error clearing flags: %2.2x\n", msg[2]); + } + smi_info->si_state = SI_NORMAL; + break; + } + + case SI_GETTING_EVENTS: + { + 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; + if (msg->rsp[2] != 0) { + /* Error getting event, probably done. */ + msg->done(msg); + + /* Take off the event flag. */ + smi_info->msg_flags &= ~EVENT_MSG_BUFFER_FULL; + handle_flags(smi_info); + } else { + smi_inc_stat(smi_info, events); + + /* + * Do this before we deliver the message + * because delivering the message releases the + * lock and something else can mess with the + * state. + */ + handle_flags(smi_info); + + deliver_recv_msg(smi_info, msg); + } + break; + } + + case SI_GETTING_MESSAGES: + { + 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; + if (msg->rsp[2] != 0) { + /* Error getting event, probably done. */ + msg->done(msg); + + /* Take off the msg flag. */ + smi_info->msg_flags &= ~RECEIVE_MSG_AVAIL; + handle_flags(smi_info); + } else { + smi_inc_stat(smi_info, incoming_messages); + + /* + * Do this before we deliver the message + * because delivering the message releases the + * lock and something else can mess with the + * state. + */ + handle_flags(smi_info); + + deliver_recv_msg(smi_info, msg); + } + break; + } + + case SI_CHECKING_ENABLES: + { + unsigned char msg[4]; + u8 enables; + bool irq_on; + + /* We got the flags from the SMI, now handle them. */ + smi_info->handlers->get_result(smi_info->si_sm, msg, 4); + if (msg[2] != 0) { + dev_warn_ratelimited(smi_info->io.dev, + "Couldn't get irq info: %x,\n" + "Maybe ok, but ipmi might run very slowly.\n", + msg[2]); + smi_info->si_state = SI_NORMAL; + break; + } + enables = current_global_enables(smi_info, 0, &irq_on); + if (smi_info->io.si_type == SI_BT) + /* BT has its own interrupt enable bit. */ + check_bt_irq(smi_info, irq_on); + if (enables != (msg[3] & GLOBAL_ENABLES_MASK)) { + /* Enables are not correct, fix them. */ + msg[0] = (IPMI_NETFN_APP_REQUEST << 2); + msg[1] = IPMI_SET_BMC_GLOBAL_ENABLES_CMD; + msg[2] = enables | (msg[3] & ~GLOBAL_ENABLES_MASK); + smi_info->handlers->start_transaction( + smi_info->si_sm, msg, 3); + smi_info->si_state = SI_SETTING_ENABLES; + } else if (smi_info->supports_event_msg_buff) { + smi_info->curr_msg = ipmi_alloc_smi_msg(); + if (!smi_info->curr_msg) { + smi_info->si_state = SI_NORMAL; + break; + } + start_getting_events(smi_info); + } else { + smi_info->si_state = SI_NORMAL; + } + break; + } + + case SI_SETTING_ENABLES: + { + unsigned char msg[4]; + + smi_info->handlers->get_result(smi_info->si_sm, msg, 4); + if (msg[2] != 0) + dev_warn_ratelimited(smi_info->io.dev, + "Could not set the global enables: 0x%x.\n", + msg[2]); + + if (smi_info->supports_event_msg_buff) { + smi_info->curr_msg = ipmi_alloc_smi_msg(); + if (!smi_info->curr_msg) { + smi_info->si_state = SI_NORMAL; + break; + } + start_getting_events(smi_info); + } else { + smi_info->si_state = SI_NORMAL; + } + break; + } + } +} + +/* + * Called on timeouts and events. Timeouts should pass the elapsed + * time, interrupts should pass in zero. Must be called with + * si_lock held and interrupts disabled. + */ +static enum si_sm_result smi_event_handler(struct smi_info *smi_info, + int time) +{ + enum si_sm_result si_sm_result; + +restart: + /* + * There used to be a loop here that waited a little while + * (around 25us) before giving up. That turned out to be + * pointless, the minimum delays I was seeing were in the 300us + * range, which is far too long to wait in an interrupt. So + * we just run until the state machine tells us something + * happened or it needs a delay. + */ + si_sm_result = smi_info->handlers->event(smi_info->si_sm, time); + time = 0; + while (si_sm_result == SI_SM_CALL_WITHOUT_DELAY) + si_sm_result = smi_info->handlers->event(smi_info->si_sm, 0); + + if (si_sm_result == SI_SM_TRANSACTION_COMPLETE) { + smi_inc_stat(smi_info, complete_transactions); + + handle_transaction_done(smi_info); + goto restart; + } else if (si_sm_result == SI_SM_HOSED) { + smi_inc_stat(smi_info, hosed_count); + + /* + * Do the before return_hosed_msg, because that + * releases the lock. + */ + smi_info->si_state = SI_NORMAL; + if (smi_info->curr_msg != NULL) { + /* + * If we were handling a user message, format + * a response to send to the upper layer to + * tell it about the error. + */ + return_hosed_msg(smi_info, IPMI_ERR_UNSPECIFIED); + } + goto restart; + } + + /* + * We prefer handling attn over new messages. But don't do + * this if there is not yet an upper layer to handle anything. + */ + if (si_sm_result == SI_SM_ATTN || smi_info->got_attn) { + unsigned char msg[2]; + + if (smi_info->si_state != SI_NORMAL) { + /* + * We got an ATTN, but we are doing something else. + * Handle the ATTN later. + */ + smi_info->got_attn = true; + } else { + smi_info->got_attn = false; + smi_inc_stat(smi_info, attentions); + + /* + * Got a attn, send down a get message flags to see + * what's causing it. It would be better to handle + * this in the upper layer, but due to the way + * interrupts work with the SMI, that's not really + * possible. + */ + msg[0] = (IPMI_NETFN_APP_REQUEST << 2); + msg[1] = IPMI_GET_MSG_FLAGS_CMD; + + start_new_msg(smi_info, msg, 2); + smi_info->si_state = SI_GETTING_FLAGS; + goto restart; + } + } + + /* If we are currently idle, try to start the next message. */ + if (si_sm_result == SI_SM_IDLE) { + smi_inc_stat(smi_info, idles); + + si_sm_result = start_next_msg(smi_info); + if (si_sm_result != SI_SM_IDLE) + goto restart; + } + + if ((si_sm_result == SI_SM_IDLE) + && (atomic_read(&smi_info->req_events))) { + /* + * We are idle and the upper layer requested that I fetch + * events, so do so. + */ + atomic_set(&smi_info->req_events, 0); + + /* + * Take this opportunity to check the interrupt and + * message enable state for the BMC. The BMC can be + * asynchronously reset, and may thus get interrupts + * disable and messages disabled. + */ + if (smi_info->supports_event_msg_buff || smi_info->io.irq) { + start_check_enables(smi_info); + } else { + smi_info->curr_msg = alloc_msg_handle_irq(smi_info); + if (!smi_info->curr_msg) + goto out; + + start_getting_events(smi_info); + } + goto restart; + } + + if (si_sm_result == SI_SM_IDLE && smi_info->timer_running) { + /* Ok it if fails, the timer will just go off. */ + if (del_timer(&smi_info->si_timer)) + smi_info->timer_running = false; + } + +out: + return si_sm_result; +} + +static void check_start_timer_thread(struct smi_info *smi_info) +{ + if (smi_info->si_state == SI_NORMAL && smi_info->curr_msg == NULL) { + smi_mod_timer(smi_info, jiffies + SI_TIMEOUT_JIFFIES); + + if (smi_info->thread) + wake_up_process(smi_info->thread); + + start_next_msg(smi_info); + smi_event_handler(smi_info, 0); + } +} + +static void flush_messages(void *send_info) +{ + struct smi_info *smi_info = send_info; + enum si_sm_result result; + + /* + * Currently, this function is called only in run-to-completion + * mode. This means we are single-threaded, no need for locks. + */ + result = smi_event_handler(smi_info, 0); + while (result != SI_SM_IDLE) { + udelay(SI_SHORT_TIMEOUT_USEC); + result = smi_event_handler(smi_info, SI_SHORT_TIMEOUT_USEC); + } +} + +static void sender(void *send_info, + struct ipmi_smi_msg *msg) +{ + struct smi_info *smi_info = send_info; + unsigned long flags; + + debug_timestamp(smi_info, "Enqueue"); + + if (smi_info->run_to_completion) { + /* + * If we are running to completion, start it. Upper + * layer will call flush_messages to clear it out. + */ + smi_info->waiting_msg = msg; + return; + } + + spin_lock_irqsave(&smi_info->si_lock, flags); + /* + * The following two lines don't need to be under the lock for + * the lock's sake, but they do need SMP memory barriers to + * avoid getting things out of order. We are already claiming + * the lock, anyway, so just do it under the lock to avoid the + * ordering problem. + */ + BUG_ON(smi_info->waiting_msg); + smi_info->waiting_msg = msg; + check_start_timer_thread(smi_info); + spin_unlock_irqrestore(&smi_info->si_lock, flags); +} + +static void set_run_to_completion(void *send_info, bool i_run_to_completion) +{ + struct smi_info *smi_info = send_info; + + smi_info->run_to_completion = i_run_to_completion; + if (i_run_to_completion) + flush_messages(smi_info); +} + +/* + * Use -1 as a special constant to tell that we are spinning in kipmid + * looking for something and not delaying between checks + */ +#define IPMI_TIME_NOT_BUSY ns_to_ktime(-1ull) +static inline bool ipmi_thread_busy_wait(enum si_sm_result smi_result, + const struct smi_info *smi_info, + ktime_t *busy_until) +{ + unsigned int max_busy_us = 0; + + if (smi_info->si_num < num_max_busy_us) + max_busy_us = kipmid_max_busy_us[smi_info->si_num]; + if (max_busy_us == 0 || smi_result != SI_SM_CALL_WITH_DELAY) + *busy_until = IPMI_TIME_NOT_BUSY; + else if (*busy_until == IPMI_TIME_NOT_BUSY) { + *busy_until = ktime_get() + max_busy_us * NSEC_PER_USEC; + } else { + if (unlikely(ktime_get() > *busy_until)) { + *busy_until = IPMI_TIME_NOT_BUSY; + return false; + } + } + return true; +} + + +/* + * A busy-waiting loop for speeding up IPMI operation. + * + * Lousy hardware makes this hard. This is only enabled for systems + * that are not BT and do not have interrupts. It starts spinning + * when an operation is complete or until max_busy tells it to stop + * (if that is enabled). See the paragraph on kimid_max_busy_us in + * Documentation/driver-api/ipmi.rst for details. + */ +static int ipmi_thread(void *data) +{ + struct smi_info *smi_info = data; + unsigned long flags; + enum si_sm_result smi_result; + ktime_t busy_until = IPMI_TIME_NOT_BUSY; + + set_user_nice(current, MAX_NICE); + while (!kthread_should_stop()) { + int busy_wait; + + spin_lock_irqsave(&(smi_info->si_lock), flags); + smi_result = smi_event_handler(smi_info, 0); + + /* + * If the driver is doing something, there is a possible + * race with the timer. If the timer handler see idle, + * and the thread here sees something else, the timer + * handler won't restart the timer even though it is + * required. So start it here if necessary. + */ + if (smi_result != SI_SM_IDLE && !smi_info->timer_running) + smi_mod_timer(smi_info, jiffies + SI_TIMEOUT_JIFFIES); + + spin_unlock_irqrestore(&(smi_info->si_lock), flags); + busy_wait = ipmi_thread_busy_wait(smi_result, smi_info, + &busy_until); + if (smi_result == SI_SM_CALL_WITHOUT_DELAY) { + ; /* do nothing */ + } else if (smi_result == SI_SM_CALL_WITH_DELAY && busy_wait) { + /* + * In maintenance mode we run as fast as + * possible to allow firmware updates to + * complete as fast as possible, but normally + * don't bang on the scheduler. + */ + if (smi_info->in_maintenance_mode) + schedule(); + else + usleep_range(100, 200); + } else if (smi_result == SI_SM_IDLE) { + if (atomic_read(&smi_info->need_watch)) { + schedule_timeout_interruptible(100); + } else { + /* Wait to be woken up when we are needed. */ + __set_current_state(TASK_INTERRUPTIBLE); + schedule(); + } + } else { + schedule_timeout_interruptible(1); + } + } + return 0; +} + + +static void poll(void *send_info) +{ + struct smi_info *smi_info = send_info; + unsigned long flags = 0; + bool run_to_completion = smi_info->run_to_completion; + + /* + * Make sure there is some delay in the poll loop so we can + * drive time forward and timeout things. + */ + udelay(10); + if (!run_to_completion) + spin_lock_irqsave(&smi_info->si_lock, flags); + smi_event_handler(smi_info, 10); + if (!run_to_completion) + spin_unlock_irqrestore(&smi_info->si_lock, flags); +} + +static void request_events(void *send_info) +{ + struct smi_info *smi_info = send_info; + + if (!smi_info->has_event_buffer) + return; + + atomic_set(&smi_info->req_events, 1); +} + +static void set_need_watch(void *send_info, unsigned int watch_mask) +{ + struct smi_info *smi_info = send_info; + unsigned long flags; + int enable; + + enable = !!watch_mask; + + atomic_set(&smi_info->need_watch, enable); + spin_lock_irqsave(&smi_info->si_lock, flags); + check_start_timer_thread(smi_info); + spin_unlock_irqrestore(&smi_info->si_lock, flags); +} + +static void smi_timeout(struct timer_list *t) +{ + struct smi_info *smi_info = from_timer(smi_info, t, si_timer); + enum si_sm_result smi_result; + unsigned long flags; + unsigned long jiffies_now; + long time_diff; + long timeout; + + spin_lock_irqsave(&(smi_info->si_lock), flags); + debug_timestamp(smi_info, "Timer"); + + jiffies_now = jiffies; + time_diff = (((long)jiffies_now - (long)smi_info->last_timeout_jiffies) + * SI_USEC_PER_JIFFY); + smi_result = smi_event_handler(smi_info, time_diff); + + if ((smi_info->io.irq) && (!smi_info->interrupt_disabled)) { + /* Running with interrupts, only do long timeouts. */ + timeout = jiffies + SI_TIMEOUT_JIFFIES; + smi_inc_stat(smi_info, long_timeouts); + goto do_mod_timer; + } + + /* + * If the state machine asks for a short delay, then shorten + * the timer timeout. + */ + if (smi_result == SI_SM_CALL_WITH_DELAY) { + smi_inc_stat(smi_info, short_timeouts); + timeout = jiffies + 1; + } else { + smi_inc_stat(smi_info, long_timeouts); + timeout = jiffies + SI_TIMEOUT_JIFFIES; + } + +do_mod_timer: + if (smi_result != SI_SM_IDLE) + smi_mod_timer(smi_info, timeout); + else + smi_info->timer_running = false; + spin_unlock_irqrestore(&(smi_info->si_lock), flags); +} + +irqreturn_t ipmi_si_irq_handler(int irq, void *data) +{ + struct smi_info *smi_info = data; + unsigned long flags; + + if (smi_info->io.si_type == SI_BT) + /* We need to clear the IRQ flag for the BT interface. */ + smi_info->io.outputb(&smi_info->io, IPMI_BT_INTMASK_REG, + IPMI_BT_INTMASK_CLEAR_IRQ_BIT + | IPMI_BT_INTMASK_ENABLE_IRQ_BIT); + + spin_lock_irqsave(&(smi_info->si_lock), flags); + + smi_inc_stat(smi_info, interrupts); + + debug_timestamp(smi_info, "Interrupt"); + + smi_event_handler(smi_info, 0); + spin_unlock_irqrestore(&(smi_info->si_lock), flags); + return IRQ_HANDLED; +} + +static int smi_start_processing(void *send_info, + struct ipmi_smi *intf) +{ + struct smi_info *new_smi = send_info; + int enable = 0; + + new_smi->intf = intf; + + /* Set up the timer that drives the interface. */ + timer_setup(&new_smi->si_timer, smi_timeout, 0); + new_smi->timer_can_start = true; + smi_mod_timer(new_smi, jiffies + SI_TIMEOUT_JIFFIES); + + /* Try to claim any interrupts. */ + if (new_smi->io.irq_setup) { + new_smi->io.irq_handler_data = new_smi; + new_smi->io.irq_setup(&new_smi->io); + } + + /* + * Check if the user forcefully enabled the daemon. + */ + if (new_smi->si_num < num_force_kipmid) + enable = force_kipmid[new_smi->si_num]; + /* + * The BT interface is efficient enough to not need a thread, + * and there is no need for a thread if we have interrupts. + */ + else if ((new_smi->io.si_type != SI_BT) && (!new_smi->io.irq)) + enable = 1; + + if (enable) { + new_smi->thread = kthread_run(ipmi_thread, new_smi, + "kipmi%d", new_smi->si_num); + if (IS_ERR(new_smi->thread)) { + dev_notice(new_smi->io.dev, + "Could not start kernel thread due to error %ld, only using timers to drive the interface\n", + PTR_ERR(new_smi->thread)); + new_smi->thread = NULL; + } + } + + return 0; +} + +static int get_smi_info(void *send_info, struct ipmi_smi_info *data) +{ + struct smi_info *smi = send_info; + + data->addr_src = smi->io.addr_source; + data->dev = smi->io.dev; + data->addr_info = smi->io.addr_info; + get_device(smi->io.dev); + + return 0; +} + +static void set_maintenance_mode(void *send_info, bool enable) +{ + struct smi_info *smi_info = send_info; + + if (!enable) + atomic_set(&smi_info->req_events, 0); + smi_info->in_maintenance_mode = enable; +} + +static void shutdown_smi(void *send_info); +static const struct ipmi_smi_handlers handlers = { + .owner = THIS_MODULE, + .start_processing = smi_start_processing, + .shutdown = shutdown_smi, + .get_smi_info = get_smi_info, + .sender = sender, + .request_events = request_events, + .set_need_watch = set_need_watch, + .set_maintenance_mode = set_maintenance_mode, + .set_run_to_completion = set_run_to_completion, + .flush_messages = flush_messages, + .poll = poll, +}; + +static LIST_HEAD(smi_infos); +static DEFINE_MUTEX(smi_infos_lock); +static int smi_num; /* Used to sequence the SMIs */ + +static const char * const addr_space_to_str[] = { "i/o", "mem" }; + +module_param_array(force_kipmid, int, &num_force_kipmid, 0); +MODULE_PARM_DESC(force_kipmid, + "Force the kipmi daemon to be enabled (1) or disabled(0). Normally the IPMI driver auto-detects this, but the value may be overridden by this parm."); +module_param(unload_when_empty, bool, 0); +MODULE_PARM_DESC(unload_when_empty, + "Unload the module if no interfaces are specified or found, default is 1. Setting to 0 is useful for hot add of devices using hotmod."); +module_param_array(kipmid_max_busy_us, uint, &num_max_busy_us, 0644); +MODULE_PARM_DESC(kipmid_max_busy_us, + "Max time (in microseconds) to busy-wait for IPMI data before sleeping. 0 (default) means to wait forever. Set to 100-500 if kipmid is using up a lot of CPU time."); + +void ipmi_irq_finish_setup(struct si_sm_io *io) +{ + if (io->si_type == SI_BT) + /* Enable the interrupt in the BT interface. */ + io->outputb(io, IPMI_BT_INTMASK_REG, + IPMI_BT_INTMASK_ENABLE_IRQ_BIT); +} + +void ipmi_irq_start_cleanup(struct si_sm_io *io) +{ + if (io->si_type == SI_BT) + /* Disable the interrupt in the BT interface. */ + io->outputb(io, IPMI_BT_INTMASK_REG, 0); +} + +static void std_irq_cleanup(struct si_sm_io *io) +{ + ipmi_irq_start_cleanup(io); + free_irq(io->irq, io->irq_handler_data); +} + +int ipmi_std_irq_setup(struct si_sm_io *io) +{ + int rv; + + if (!io->irq) + return 0; + + rv = request_irq(io->irq, + ipmi_si_irq_handler, + IRQF_SHARED, + SI_DEVICE_NAME, + io->irq_handler_data); + if (rv) { + dev_warn(io->dev, "%s unable to claim interrupt %d, running polled\n", + SI_DEVICE_NAME, io->irq); + io->irq = 0; + } else { + io->irq_cleanup = std_irq_cleanup; + ipmi_irq_finish_setup(io); + dev_info(io->dev, "Using irq %d\n", io->irq); + } + + return rv; +} + +static int wait_for_msg_done(struct smi_info *smi_info) +{ + enum si_sm_result smi_result; + + smi_result = smi_info->handlers->event(smi_info->si_sm, 0); + for (;;) { + if (smi_result == SI_SM_CALL_WITH_DELAY || + smi_result == SI_SM_CALL_WITH_TICK_DELAY) { + schedule_timeout_uninterruptible(1); + smi_result = smi_info->handlers->event( + smi_info->si_sm, jiffies_to_usecs(1)); + } else if (smi_result == SI_SM_CALL_WITHOUT_DELAY) { + smi_result = smi_info->handlers->event( + smi_info->si_sm, 0); + } else + break; + } + if (smi_result == SI_SM_HOSED) + /* + * We couldn't get the state machine to run, so whatever's at + * the port is probably not an IPMI SMI interface. + */ + return -ENODEV; + + return 0; +} + +static int try_get_dev_id(struct smi_info *smi_info) +{ + unsigned char msg[2]; + unsigned char *resp; + unsigned long resp_len; + int rv = 0; + unsigned int retry_count = 0; + + resp = kmalloc(IPMI_MAX_MSG_LENGTH, GFP_KERNEL); + if (!resp) + return -ENOMEM; + + /* + * Do a Get Device ID command, since it comes back with some + * useful info. + */ + msg[0] = IPMI_NETFN_APP_REQUEST << 2; + msg[1] = IPMI_GET_DEVICE_ID_CMD; + +retry: + smi_info->handlers->start_transaction(smi_info->si_sm, msg, 2); + + rv = wait_for_msg_done(smi_info); + if (rv) + goto out; + + resp_len = smi_info->handlers->get_result(smi_info->si_sm, + resp, IPMI_MAX_MSG_LENGTH); + + /* Check and record info from the get device id, in case we need it. */ + rv = ipmi_demangle_device_id(resp[0] >> 2, resp[1], + resp + 2, resp_len - 2, &smi_info->device_id); + if (rv) { + /* record completion code */ + unsigned char cc = *(resp + 2); + + if (cc != IPMI_CC_NO_ERROR && + ++retry_count <= GET_DEVICE_ID_MAX_RETRY) { + dev_warn_ratelimited(smi_info->io.dev, + "BMC returned 0x%2.2x, retry get bmc device id\n", + cc); + goto retry; + } + } + +out: + kfree(resp); + return rv; +} + +static int get_global_enables(struct smi_info *smi_info, u8 *enables) +{ + unsigned char msg[3]; + unsigned char *resp; + unsigned long resp_len; + int rv; + + resp = kmalloc(IPMI_MAX_MSG_LENGTH, GFP_KERNEL); + if (!resp) + return -ENOMEM; + + 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); + + rv = wait_for_msg_done(smi_info); + if (rv) { + dev_warn(smi_info->io.dev, + "Error getting response from get global enables command: %d\n", + rv); + goto out; + } + + resp_len = smi_info->handlers->get_result(smi_info->si_sm, + resp, IPMI_MAX_MSG_LENGTH); + + if (resp_len < 4 || + resp[0] != (IPMI_NETFN_APP_REQUEST | 1) << 2 || + resp[1] != IPMI_GET_BMC_GLOBAL_ENABLES_CMD || + resp[2] != 0) { + dev_warn(smi_info->io.dev, + "Invalid return from get global enables command: %ld %x %x %x\n", + resp_len, resp[0], resp[1], resp[2]); + rv = -EINVAL; + goto out; + } else { + *enables = resp[3]; + } + +out: + kfree(resp); + return rv; +} + +/* + * Returns 1 if it gets an error from the command. + */ +static int set_global_enables(struct smi_info *smi_info, u8 enables) +{ + unsigned char msg[3]; + unsigned char *resp; + unsigned long resp_len; + int rv; + + resp = kmalloc(IPMI_MAX_MSG_LENGTH, GFP_KERNEL); + if (!resp) + return -ENOMEM; + + msg[0] = IPMI_NETFN_APP_REQUEST << 2; + msg[1] = IPMI_SET_BMC_GLOBAL_ENABLES_CMD; + msg[2] = enables; + smi_info->handlers->start_transaction(smi_info->si_sm, msg, 3); + + rv = wait_for_msg_done(smi_info); + if (rv) { + dev_warn(smi_info->io.dev, + "Error getting response from set global enables command: %d\n", + rv); + goto out; + } + + resp_len = smi_info->handlers->get_result(smi_info->si_sm, + resp, IPMI_MAX_MSG_LENGTH); + + if (resp_len < 3 || + resp[0] != (IPMI_NETFN_APP_REQUEST | 1) << 2 || + resp[1] != IPMI_SET_BMC_GLOBAL_ENABLES_CMD) { + dev_warn(smi_info->io.dev, + "Invalid return from set global enables command: %ld %x %x\n", + resp_len, resp[0], resp[1]); + rv = -EINVAL; + goto out; + } + + if (resp[2] != 0) + rv = 1; + +out: + kfree(resp); + return rv; +} + +/* + * Some BMCs do not support clearing the receive irq bit in the global + * enables (even if they don't support interrupts on the BMC). Check + * for this and handle it properly. + */ +static void check_clr_rcv_irq(struct smi_info *smi_info) +{ + u8 enables = 0; + int rv; + + rv = get_global_enables(smi_info, &enables); + if (!rv) { + if ((enables & IPMI_BMC_RCV_MSG_INTR) == 0) + /* Already clear, should work ok. */ + return; + + enables &= ~IPMI_BMC_RCV_MSG_INTR; + rv = set_global_enables(smi_info, enables); + } + + if (rv < 0) { + dev_err(smi_info->io.dev, + "Cannot check clearing the rcv irq: %d\n", rv); + return; + } + + if (rv) { + /* + * An error when setting the event buffer bit means + * clearing the bit is not supported. + */ + dev_warn(smi_info->io.dev, + "The BMC does not support clearing the recv irq bit, compensating, but the BMC needs to be fixed.\n"); + smi_info->cannot_disable_irq = true; + } +} + +/* + * Some BMCs do not support setting the interrupt bits in the global + * enables even if they support interrupts. Clearly bad, but we can + * compensate. + */ +static void check_set_rcv_irq(struct smi_info *smi_info) +{ + u8 enables = 0; + int rv; + + if (!smi_info->io.irq) + return; + + rv = get_global_enables(smi_info, &enables); + if (!rv) { + enables |= IPMI_BMC_RCV_MSG_INTR; + rv = set_global_enables(smi_info, enables); + } + + if (rv < 0) { + dev_err(smi_info->io.dev, + "Cannot check setting the rcv irq: %d\n", rv); + return; + } + + if (rv) { + /* + * An error when setting the event buffer bit means + * setting the bit is not supported. + */ + dev_warn(smi_info->io.dev, + "The BMC does not support setting the recv irq bit, compensating, but the BMC needs to be fixed.\n"); + smi_info->cannot_disable_irq = true; + smi_info->irq_enable_broken = true; + } +} + +static int try_enable_event_buffer(struct smi_info *smi_info) +{ + unsigned char msg[3]; + unsigned char *resp; + unsigned long resp_len; + int rv = 0; + + resp = kmalloc(IPMI_MAX_MSG_LENGTH, GFP_KERNEL); + if (!resp) + return -ENOMEM; + + 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); + + rv = wait_for_msg_done(smi_info); + if (rv) { + pr_warn("Error getting response from get global enables command, the event buffer is not enabled\n"); + goto out; + } + + resp_len = smi_info->handlers->get_result(smi_info->si_sm, + resp, IPMI_MAX_MSG_LENGTH); + + if (resp_len < 4 || + resp[0] != (IPMI_NETFN_APP_REQUEST | 1) << 2 || + resp[1] != IPMI_GET_BMC_GLOBAL_ENABLES_CMD || + resp[2] != 0) { + pr_warn("Invalid return from get global enables command, cannot enable the event buffer\n"); + rv = -EINVAL; + goto out; + } + + if (resp[3] & IPMI_BMC_EVT_MSG_BUFF) { + /* buffer is already enabled, nothing to do. */ + smi_info->supports_event_msg_buff = true; + goto out; + } + + msg[0] = IPMI_NETFN_APP_REQUEST << 2; + msg[1] = IPMI_SET_BMC_GLOBAL_ENABLES_CMD; + msg[2] = resp[3] | IPMI_BMC_EVT_MSG_BUFF; + smi_info->handlers->start_transaction(smi_info->si_sm, msg, 3); + + rv = wait_for_msg_done(smi_info); + if (rv) { + pr_warn("Error getting response from set global, enables command, the event buffer is not enabled\n"); + goto out; + } + + resp_len = smi_info->handlers->get_result(smi_info->si_sm, + resp, IPMI_MAX_MSG_LENGTH); + + if (resp_len < 3 || + resp[0] != (IPMI_NETFN_APP_REQUEST | 1) << 2 || + resp[1] != IPMI_SET_BMC_GLOBAL_ENABLES_CMD) { + pr_warn("Invalid return from get global, enables command, not enable the event buffer\n"); + rv = -EINVAL; + goto out; + } + + if (resp[2] != 0) + /* + * An error when setting the event buffer bit means + * that the event buffer is not supported. + */ + rv = -ENOENT; + else + smi_info->supports_event_msg_buff = true; + +out: + kfree(resp); + return rv; +} + +#define IPMI_SI_ATTR(name) \ +static ssize_t name##_show(struct device *dev, \ + struct device_attribute *attr, \ + char *buf) \ +{ \ + struct smi_info *smi_info = dev_get_drvdata(dev); \ + \ + return sysfs_emit(buf, "%u\n", smi_get_stat(smi_info, name)); \ +} \ +static DEVICE_ATTR_RO(name) + +static ssize_t type_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct smi_info *smi_info = dev_get_drvdata(dev); + + return sysfs_emit(buf, "%s\n", si_to_str[smi_info->io.si_type]); +} +static DEVICE_ATTR_RO(type); + +static ssize_t interrupts_enabled_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct smi_info *smi_info = dev_get_drvdata(dev); + int enabled = smi_info->io.irq && !smi_info->interrupt_disabled; + + return sysfs_emit(buf, "%d\n", enabled); +} +static DEVICE_ATTR_RO(interrupts_enabled); + +IPMI_SI_ATTR(short_timeouts); +IPMI_SI_ATTR(long_timeouts); +IPMI_SI_ATTR(idles); +IPMI_SI_ATTR(interrupts); +IPMI_SI_ATTR(attentions); +IPMI_SI_ATTR(flag_fetches); +IPMI_SI_ATTR(hosed_count); +IPMI_SI_ATTR(complete_transactions); +IPMI_SI_ATTR(events); +IPMI_SI_ATTR(watchdog_pretimeouts); +IPMI_SI_ATTR(incoming_messages); + +static ssize_t params_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct smi_info *smi_info = dev_get_drvdata(dev); + + return sysfs_emit(buf, + "%s,%s,0x%lx,rsp=%d,rsi=%d,rsh=%d,irq=%d,ipmb=%d\n", + si_to_str[smi_info->io.si_type], + addr_space_to_str[smi_info->io.addr_space], + smi_info->io.addr_data, + smi_info->io.regspacing, + smi_info->io.regsize, + smi_info->io.regshift, + smi_info->io.irq, + smi_info->io.slave_addr); +} +static DEVICE_ATTR_RO(params); + +static struct attribute *ipmi_si_dev_attrs[] = { + &dev_attr_type.attr, + &dev_attr_interrupts_enabled.attr, + &dev_attr_short_timeouts.attr, + &dev_attr_long_timeouts.attr, + &dev_attr_idles.attr, + &dev_attr_interrupts.attr, + &dev_attr_attentions.attr, + &dev_attr_flag_fetches.attr, + &dev_attr_hosed_count.attr, + &dev_attr_complete_transactions.attr, + &dev_attr_events.attr, + &dev_attr_watchdog_pretimeouts.attr, + &dev_attr_incoming_messages.attr, + &dev_attr_params.attr, + NULL +}; + +static const struct attribute_group ipmi_si_dev_attr_group = { + .attrs = ipmi_si_dev_attrs, +}; + +/* + * oem_data_avail_to_receive_msg_avail + * @info - smi_info structure with msg_flags set + * + * Converts flags from OEM_DATA_AVAIL to RECEIVE_MSG_AVAIL + * Returns 1 indicating need to re-run handle_flags(). + */ +static int oem_data_avail_to_receive_msg_avail(struct smi_info *smi_info) +{ + smi_info->msg_flags = ((smi_info->msg_flags & ~OEM_DATA_AVAIL) | + RECEIVE_MSG_AVAIL); + return 1; +} + +/* + * setup_dell_poweredge_oem_data_handler + * @info - smi_info.device_id must be populated + * + * Systems that match, but have firmware version < 1.40 may assert + * OEM0_DATA_AVAIL on their own, without being told via Set Flags that + * it's safe to do so. Such systems will de-assert OEM1_DATA_AVAIL + * upon receipt of IPMI_GET_MSG_CMD, so we should treat these flags + * as RECEIVE_MSG_AVAIL instead. + * + * As Dell has no plans to release IPMI 1.5 firmware that *ever* + * assert the OEM[012] bits, and if it did, the driver would have to + * change to handle that properly, we don't actually check for the + * firmware version. + * Device ID = 0x20 BMC on PowerEdge 8G servers + * Device Revision = 0x80 + * Firmware Revision1 = 0x01 BMC version 1.40 + * Firmware Revision2 = 0x40 BCD encoded + * IPMI Version = 0x51 IPMI 1.5 + * Manufacturer ID = A2 02 00 Dell IANA + * + * Additionally, PowerEdge systems with IPMI < 1.5 may also assert + * OEM0_DATA_AVAIL and needs to be treated as RECEIVE_MSG_AVAIL. + * + */ +#define DELL_POWEREDGE_8G_BMC_DEVICE_ID 0x20 +#define DELL_POWEREDGE_8G_BMC_DEVICE_REV 0x80 +#define DELL_POWEREDGE_8G_BMC_IPMI_VERSION 0x51 +#define DELL_IANA_MFR_ID 0x0002a2 +static void setup_dell_poweredge_oem_data_handler(struct smi_info *smi_info) +{ + struct ipmi_device_id *id = &smi_info->device_id; + if (id->manufacturer_id == DELL_IANA_MFR_ID) { + if (id->device_id == DELL_POWEREDGE_8G_BMC_DEVICE_ID && + id->device_revision == DELL_POWEREDGE_8G_BMC_DEVICE_REV && + id->ipmi_version == DELL_POWEREDGE_8G_BMC_IPMI_VERSION) { + smi_info->oem_data_avail_handler = + oem_data_avail_to_receive_msg_avail; + } else if (ipmi_version_major(id) < 1 || + (ipmi_version_major(id) == 1 && + ipmi_version_minor(id) < 5)) { + smi_info->oem_data_avail_handler = + oem_data_avail_to_receive_msg_avail; + } + } +} + +#define CANNOT_RETURN_REQUESTED_LENGTH 0xCA +static void return_hosed_msg_badsize(struct smi_info *smi_info) +{ + struct ipmi_smi_msg *msg = smi_info->curr_msg; + + /* Make it a response */ + msg->rsp[0] = msg->data[0] | 4; + msg->rsp[1] = msg->data[1]; + msg->rsp[2] = CANNOT_RETURN_REQUESTED_LENGTH; + msg->rsp_size = 3; + smi_info->curr_msg = NULL; + deliver_recv_msg(smi_info, msg); +} + +/* + * dell_poweredge_bt_xaction_handler + * @info - smi_info.device_id must be populated + * + * Dell PowerEdge servers with the BT interface (x6xx and 1750) will + * not respond to a Get SDR command if the length of the data + * requested is exactly 0x3A, which leads to command timeouts and no + * data returned. This intercepts such commands, and causes userspace + * callers to try again with a different-sized buffer, which succeeds. + */ + +#define STORAGE_NETFN 0x0A +#define STORAGE_CMD_GET_SDR 0x23 +static int dell_poweredge_bt_xaction_handler(struct notifier_block *self, + unsigned long unused, + void *in) +{ + struct smi_info *smi_info = in; + unsigned char *data = smi_info->curr_msg->data; + unsigned int size = smi_info->curr_msg->data_size; + if (size >= 8 && + (data[0]>>2) == STORAGE_NETFN && + data[1] == STORAGE_CMD_GET_SDR && + data[7] == 0x3A) { + return_hosed_msg_badsize(smi_info); + return NOTIFY_STOP; + } + return NOTIFY_DONE; +} + +static struct notifier_block dell_poweredge_bt_xaction_notifier = { + .notifier_call = dell_poweredge_bt_xaction_handler, +}; + +/* + * setup_dell_poweredge_bt_xaction_handler + * @info - smi_info.device_id must be filled in already + * + * Fills in smi_info.device_id.start_transaction_pre_hook + * when we know what function to use there. + */ +static void +setup_dell_poweredge_bt_xaction_handler(struct smi_info *smi_info) +{ + struct ipmi_device_id *id = &smi_info->device_id; + if (id->manufacturer_id == DELL_IANA_MFR_ID && + smi_info->io.si_type == SI_BT) + register_xaction_notifier(&dell_poweredge_bt_xaction_notifier); +} + +/* + * setup_oem_data_handler + * @info - smi_info.device_id must be filled in already + * + * Fills in smi_info.device_id.oem_data_available_handler + * when we know what function to use there. + */ + +static void setup_oem_data_handler(struct smi_info *smi_info) +{ + setup_dell_poweredge_oem_data_handler(smi_info); +} + +static void setup_xaction_handlers(struct smi_info *smi_info) +{ + setup_dell_poweredge_bt_xaction_handler(smi_info); +} + +static void check_for_broken_irqs(struct smi_info *smi_info) +{ + check_clr_rcv_irq(smi_info); + check_set_rcv_irq(smi_info); +} + +static inline void stop_timer_and_thread(struct smi_info *smi_info) +{ + if (smi_info->thread != NULL) { + kthread_stop(smi_info->thread); + smi_info->thread = NULL; + } + + smi_info->timer_can_start = false; + del_timer_sync(&smi_info->si_timer); +} + +static struct smi_info *find_dup_si(struct smi_info *info) +{ + struct smi_info *e; + + list_for_each_entry(e, &smi_infos, link) { + if (e->io.addr_space != info->io.addr_space) + continue; + if (e->io.addr_data == info->io.addr_data) { + /* + * This is a cheap hack, ACPI doesn't have a defined + * slave address but SMBIOS does. Pick it up from + * any source that has it available. + */ + if (info->io.slave_addr && !e->io.slave_addr) + e->io.slave_addr = info->io.slave_addr; + return e; + } + } + + return NULL; +} + +int ipmi_si_add_smi(struct si_sm_io *io) +{ + int rv = 0; + struct smi_info *new_smi, *dup; + + /* + * If the user gave us a hard-coded device at the same + * address, they presumably want us to use it and not what is + * in the firmware. + */ + if (io->addr_source != SI_HARDCODED && io->addr_source != SI_HOTMOD && + ipmi_si_hardcode_match(io->addr_space, io->addr_data)) { + dev_info(io->dev, + "Hard-coded device at this address already exists"); + return -ENODEV; + } + + if (!io->io_setup) { + if (io->addr_space == IPMI_IO_ADDR_SPACE) { + io->io_setup = ipmi_si_port_setup; + } else if (io->addr_space == IPMI_MEM_ADDR_SPACE) { + io->io_setup = ipmi_si_mem_setup; + } else { + return -EINVAL; + } + } + + new_smi = kzalloc(sizeof(*new_smi), GFP_KERNEL); + if (!new_smi) + return -ENOMEM; + spin_lock_init(&new_smi->si_lock); + + new_smi->io = *io; + + mutex_lock(&smi_infos_lock); + dup = find_dup_si(new_smi); + if (dup) { + if (new_smi->io.addr_source == SI_ACPI && + dup->io.addr_source == SI_SMBIOS) { + /* We prefer ACPI over SMBIOS. */ + dev_info(dup->io.dev, + "Removing SMBIOS-specified %s state machine in favor of ACPI\n", + si_to_str[new_smi->io.si_type]); + cleanup_one_si(dup); + } else { + dev_info(new_smi->io.dev, + "%s-specified %s state machine: duplicate\n", + ipmi_addr_src_to_str(new_smi->io.addr_source), + si_to_str[new_smi->io.si_type]); + rv = -EBUSY; + kfree(new_smi); + goto out_err; + } + } + + pr_info("Adding %s-specified %s state machine\n", + ipmi_addr_src_to_str(new_smi->io.addr_source), + si_to_str[new_smi->io.si_type]); + + list_add_tail(&new_smi->link, &smi_infos); + + if (initialized) + rv = try_smi_init(new_smi); +out_err: + mutex_unlock(&smi_infos_lock); + return rv; +} + +/* + * Try to start up an interface. Must be called with smi_infos_lock + * held, primarily to keep smi_num consistent, we only one to do these + * one at a time. + */ +static int try_smi_init(struct smi_info *new_smi) +{ + int rv = 0; + int i; + + pr_info("Trying %s-specified %s state machine at %s address 0x%lx, slave address 0x%x, irq %d\n", + ipmi_addr_src_to_str(new_smi->io.addr_source), + si_to_str[new_smi->io.si_type], + addr_space_to_str[new_smi->io.addr_space], + new_smi->io.addr_data, + new_smi->io.slave_addr, new_smi->io.irq); + + switch (new_smi->io.si_type) { + case SI_KCS: + new_smi->handlers = &kcs_smi_handlers; + break; + + case SI_SMIC: + new_smi->handlers = &smic_smi_handlers; + break; + + case SI_BT: + new_smi->handlers = &bt_smi_handlers; + break; + + default: + /* No support for anything else yet. */ + rv = -EIO; + goto out_err; + } + + new_smi->si_num = smi_num; + + /* Do this early so it's available for logs. */ + if (!new_smi->io.dev) { + pr_err("IPMI interface added with no device\n"); + rv = -EIO; + goto out_err; + } + + /* Allocate the state machine's data and initialize it. */ + new_smi->si_sm = kmalloc(new_smi->handlers->size(), GFP_KERNEL); + if (!new_smi->si_sm) { + rv = -ENOMEM; + goto out_err; + } + new_smi->io.io_size = new_smi->handlers->init_data(new_smi->si_sm, + &new_smi->io); + + /* Now that we know the I/O size, we can set up the I/O. */ + rv = new_smi->io.io_setup(&new_smi->io); + if (rv) { + dev_err(new_smi->io.dev, "Could not set up I/O space\n"); + goto out_err; + } + + /* Do low-level detection first. */ + if (new_smi->handlers->detect(new_smi->si_sm)) { + if (new_smi->io.addr_source) + dev_err(new_smi->io.dev, + "Interface detection failed\n"); + rv = -ENODEV; + goto out_err; + } + + /* + * Attempt a get device id command. If it fails, we probably + * don't have a BMC here. + */ + rv = try_get_dev_id(new_smi); + if (rv) { + if (new_smi->io.addr_source) + dev_err(new_smi->io.dev, + "There appears to be no BMC at this location\n"); + goto out_err; + } + + setup_oem_data_handler(new_smi); + setup_xaction_handlers(new_smi); + check_for_broken_irqs(new_smi); + + new_smi->waiting_msg = NULL; + new_smi->curr_msg = NULL; + atomic_set(&new_smi->req_events, 0); + new_smi->run_to_completion = false; + for (i = 0; i < SI_NUM_STATS; i++) + atomic_set(&new_smi->stats[i], 0); + + new_smi->interrupt_disabled = true; + atomic_set(&new_smi->need_watch, 0); + + rv = try_enable_event_buffer(new_smi); + if (rv == 0) + new_smi->has_event_buffer = true; + + /* + * Start clearing the flags before we enable interrupts or the + * timer to avoid racing with the timer. + */ + start_clear_flags(new_smi); + + /* + * IRQ is defined to be set when non-zero. req_events will + * cause a global flags check that will enable interrupts. + */ + if (new_smi->io.irq) { + new_smi->interrupt_disabled = false; + atomic_set(&new_smi->req_events, 1); + } + + dev_set_drvdata(new_smi->io.dev, new_smi); + rv = device_add_group(new_smi->io.dev, &ipmi_si_dev_attr_group); + if (rv) { + dev_err(new_smi->io.dev, + "Unable to add device attributes: error %d\n", + rv); + goto out_err; + } + new_smi->dev_group_added = true; + + rv = ipmi_register_smi(&handlers, + new_smi, + new_smi->io.dev, + new_smi->io.slave_addr); + if (rv) { + dev_err(new_smi->io.dev, + "Unable to register device: error %d\n", + rv); + goto out_err; + } + + /* Don't increment till we know we have succeeded. */ + smi_num++; + + dev_info(new_smi->io.dev, "IPMI %s interface initialized\n", + si_to_str[new_smi->io.si_type]); + + WARN_ON(new_smi->io.dev->init_name != NULL); + + out_err: + if (rv && new_smi->io.io_cleanup) { + new_smi->io.io_cleanup(&new_smi->io); + new_smi->io.io_cleanup = NULL; + } + + if (rv && new_smi->si_sm) { + kfree(new_smi->si_sm); + new_smi->si_sm = NULL; + } + + return rv; +} + +static int __init init_ipmi_si(void) +{ + struct smi_info *e; + enum ipmi_addr_src type = SI_INVALID; + + if (initialized) + return 0; + + ipmi_hardcode_init(); + + pr_info("IPMI System Interface driver\n"); + + ipmi_si_platform_init(); + + ipmi_si_pci_init(); + + ipmi_si_parisc_init(); + + /* We prefer devices with interrupts, but in the case of a machine + with multiple BMCs we assume that there will be several instances + of a given type so if we succeed in registering a type then also + try to register everything else of the same type */ + mutex_lock(&smi_infos_lock); + list_for_each_entry(e, &smi_infos, link) { + /* Try to register a device if it has an IRQ and we either + haven't successfully registered a device yet or this + device has the same type as one we successfully registered */ + if (e->io.irq && (!type || e->io.addr_source == type)) { + if (!try_smi_init(e)) { + type = e->io.addr_source; + } + } + } + + /* type will only have been set if we successfully registered an si */ + if (type) + goto skip_fallback_noirq; + + /* Fall back to the preferred device */ + + list_for_each_entry(e, &smi_infos, link) { + if (!e->io.irq && (!type || e->io.addr_source == type)) { + if (!try_smi_init(e)) { + type = e->io.addr_source; + } + } + } + +skip_fallback_noirq: + initialized = true; + mutex_unlock(&smi_infos_lock); + + if (type) + return 0; + + mutex_lock(&smi_infos_lock); + if (unload_when_empty && list_empty(&smi_infos)) { + mutex_unlock(&smi_infos_lock); + cleanup_ipmi_si(); + pr_warn("Unable to find any System Interface(s)\n"); + return -ENODEV; + } else { + mutex_unlock(&smi_infos_lock); + return 0; + } +} +module_init(init_ipmi_si); + +static void wait_msg_processed(struct smi_info *smi_info) +{ + unsigned long jiffies_now; + long time_diff; + + while (smi_info->curr_msg || (smi_info->si_state != SI_NORMAL)) { + jiffies_now = jiffies; + time_diff = (((long)jiffies_now - (long)smi_info->last_timeout_jiffies) + * SI_USEC_PER_JIFFY); + smi_event_handler(smi_info, time_diff); + schedule_timeout_uninterruptible(1); + } +} + +static void shutdown_smi(void *send_info) +{ + struct smi_info *smi_info = send_info; + + if (smi_info->dev_group_added) { + device_remove_group(smi_info->io.dev, &ipmi_si_dev_attr_group); + smi_info->dev_group_added = false; + } + if (smi_info->io.dev) + dev_set_drvdata(smi_info->io.dev, NULL); + + /* + * Make sure that interrupts, the timer and the thread are + * stopped and will not run again. + */ + smi_info->interrupt_disabled = true; + if (smi_info->io.irq_cleanup) { + smi_info->io.irq_cleanup(&smi_info->io); + smi_info->io.irq_cleanup = NULL; + } + stop_timer_and_thread(smi_info); + + /* + * Wait until we know that we are out of any interrupt + * handlers might have been running before we freed the + * interrupt. + */ + synchronize_rcu(); + + /* + * Timeouts are stopped, now make sure the interrupts are off + * in the BMC. Note that timers and CPU interrupts are off, + * so no need for locks. + */ + wait_msg_processed(smi_info); + + if (smi_info->handlers) + disable_si_irq(smi_info); + + wait_msg_processed(smi_info); + + if (smi_info->handlers) + smi_info->handlers->cleanup(smi_info->si_sm); + + if (smi_info->io.io_cleanup) { + smi_info->io.io_cleanup(&smi_info->io); + smi_info->io.io_cleanup = NULL; + } + + kfree(smi_info->si_sm); + smi_info->si_sm = NULL; + + smi_info->intf = NULL; +} + +/* + * Must be called with smi_infos_lock held, to serialize the + * smi_info->intf check. + */ +static void cleanup_one_si(struct smi_info *smi_info) +{ + if (!smi_info) + return; + + list_del(&smi_info->link); + ipmi_unregister_smi(smi_info->intf); + kfree(smi_info); +} + +void ipmi_si_remove_by_dev(struct device *dev) +{ + struct smi_info *e; + + mutex_lock(&smi_infos_lock); + list_for_each_entry(e, &smi_infos, link) { + if (e->io.dev == dev) { + cleanup_one_si(e); + break; + } + } + mutex_unlock(&smi_infos_lock); +} + +struct device *ipmi_si_remove_by_data(int addr_space, enum si_type si_type, + unsigned long addr) +{ + /* remove */ + struct smi_info *e, *tmp_e; + struct device *dev = NULL; + + mutex_lock(&smi_infos_lock); + list_for_each_entry_safe(e, tmp_e, &smi_infos, link) { + if (e->io.addr_space != addr_space) + continue; + if (e->io.si_type != si_type) + continue; + if (e->io.addr_data == addr) { + dev = get_device(e->io.dev); + cleanup_one_si(e); + } + } + mutex_unlock(&smi_infos_lock); + + return dev; +} + +static void cleanup_ipmi_si(void) +{ + struct smi_info *e, *tmp_e; + + if (!initialized) + return; + + ipmi_si_pci_shutdown(); + + ipmi_si_parisc_shutdown(); + + ipmi_si_platform_shutdown(); + + mutex_lock(&smi_infos_lock); + list_for_each_entry_safe(e, tmp_e, &smi_infos, link) + cleanup_one_si(e); + mutex_unlock(&smi_infos_lock); + + ipmi_si_hardcode_exit(); + ipmi_si_hotmod_exit(); +} +module_exit(cleanup_ipmi_si); + +MODULE_ALIAS("platform:dmi-ipmi-si"); +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Corey Minyard <minyard@mvista.com>"); +MODULE_DESCRIPTION("Interface to the IPMI driver for the KCS, SMIC, and BT system interfaces."); |