cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
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ipmi_poweroff.c (19027B)


      1// SPDX-License-Identifier: GPL-2.0+
      2/*
      3 * ipmi_poweroff.c
      4 *
      5 * MontaVista IPMI Poweroff extension to sys_reboot
      6 *
      7 * Author: MontaVista Software, Inc.
      8 *         Steven Dake <sdake@mvista.com>
      9 *         Corey Minyard <cminyard@mvista.com>
     10 *         source@mvista.com
     11 *
     12 * Copyright 2002,2004 MontaVista Software Inc.
     13 */
     14
     15#define pr_fmt(fmt) "IPMI poweroff: " fmt
     16
     17#include <linux/module.h>
     18#include <linux/moduleparam.h>
     19#include <linux/proc_fs.h>
     20#include <linux/string.h>
     21#include <linux/completion.h>
     22#include <linux/pm.h>
     23#include <linux/kdev_t.h>
     24#include <linux/ipmi.h>
     25#include <linux/ipmi_smi.h>
     26
     27static void ipmi_po_smi_gone(int if_num);
     28static void ipmi_po_new_smi(int if_num, struct device *device);
     29
     30/* Definitions for controlling power off (if the system supports it).  It
     31 * conveniently matches the IPMI chassis control values. */
     32#define IPMI_CHASSIS_POWER_DOWN		0	/* power down, the default. */
     33#define IPMI_CHASSIS_POWER_CYCLE	0x02	/* power cycle */
     34
     35/* the IPMI data command */
     36static int poweroff_powercycle;
     37
     38/* Which interface to use, -1 means the first we see. */
     39static int ifnum_to_use = -1;
     40
     41/* Our local state. */
     42static int ready;
     43static struct ipmi_user *ipmi_user;
     44static int ipmi_ifnum;
     45static void (*specific_poweroff_func)(struct ipmi_user *user);
     46
     47/* Holds the old poweroff function so we can restore it on removal. */
     48static void (*old_poweroff_func)(void);
     49
     50static int set_param_ifnum(const char *val, const struct kernel_param *kp)
     51{
     52	int rv = param_set_int(val, kp);
     53	if (rv)
     54		return rv;
     55	if ((ifnum_to_use < 0) || (ifnum_to_use == ipmi_ifnum))
     56		return 0;
     57
     58	ipmi_po_smi_gone(ipmi_ifnum);
     59	ipmi_po_new_smi(ifnum_to_use, NULL);
     60	return 0;
     61}
     62
     63module_param_call(ifnum_to_use, set_param_ifnum, param_get_int,
     64		  &ifnum_to_use, 0644);
     65MODULE_PARM_DESC(ifnum_to_use, "The interface number to use for the watchdog "
     66		 "timer.  Setting to -1 defaults to the first registered "
     67		 "interface");
     68
     69/* parameter definition to allow user to flag power cycle */
     70module_param(poweroff_powercycle, int, 0644);
     71MODULE_PARM_DESC(poweroff_powercycle,
     72		 " Set to non-zero to enable power cycle instead of power"
     73		 " down. Power cycle is contingent on hardware support,"
     74		 " otherwise it defaults back to power down.");
     75
     76/* Stuff from the get device id command. */
     77static unsigned int mfg_id;
     78static unsigned int prod_id;
     79static unsigned char capabilities;
     80static unsigned char ipmi_version;
     81
     82/*
     83 * We use our own messages for this operation, we don't let the system
     84 * allocate them, since we may be in a panic situation.  The whole
     85 * thing is single-threaded, anyway, so multiple messages are not
     86 * required.
     87 */
     88static atomic_t dummy_count = ATOMIC_INIT(0);
     89static void dummy_smi_free(struct ipmi_smi_msg *msg)
     90{
     91	atomic_dec(&dummy_count);
     92}
     93static void dummy_recv_free(struct ipmi_recv_msg *msg)
     94{
     95	atomic_dec(&dummy_count);
     96}
     97static struct ipmi_smi_msg halt_smi_msg = INIT_IPMI_SMI_MSG(dummy_smi_free);
     98static struct ipmi_recv_msg halt_recv_msg = INIT_IPMI_RECV_MSG(dummy_recv_free);
     99
    100
    101/*
    102 * Code to send a message and wait for the response.
    103 */
    104
    105static void receive_handler(struct ipmi_recv_msg *recv_msg, void *handler_data)
    106{
    107	struct completion *comp = recv_msg->user_msg_data;
    108
    109	if (comp)
    110		complete(comp);
    111}
    112
    113static const struct ipmi_user_hndl ipmi_poweroff_handler = {
    114	.ipmi_recv_hndl = receive_handler
    115};
    116
    117
    118static int ipmi_request_wait_for_response(struct ipmi_user       *user,
    119					  struct ipmi_addr       *addr,
    120					  struct kernel_ipmi_msg *send_msg)
    121{
    122	int               rv;
    123	struct completion comp;
    124
    125	init_completion(&comp);
    126
    127	rv = ipmi_request_supply_msgs(user, addr, 0, send_msg, &comp,
    128				      &halt_smi_msg, &halt_recv_msg, 0);
    129	if (rv)
    130		return rv;
    131
    132	wait_for_completion(&comp);
    133
    134	return halt_recv_msg.msg.data[0];
    135}
    136
    137/* Wait for message to complete, spinning. */
    138static int ipmi_request_in_rc_mode(struct ipmi_user       *user,
    139				   struct ipmi_addr       *addr,
    140				   struct kernel_ipmi_msg *send_msg)
    141{
    142	int rv;
    143
    144	atomic_set(&dummy_count, 2);
    145	rv = ipmi_request_supply_msgs(user, addr, 0, send_msg, NULL,
    146				      &halt_smi_msg, &halt_recv_msg, 0);
    147	if (rv) {
    148		atomic_set(&dummy_count, 0);
    149		return rv;
    150	}
    151
    152	/*
    153	 * Spin until our message is done.
    154	 */
    155	while (atomic_read(&dummy_count) > 0) {
    156		ipmi_poll_interface(user);
    157		cpu_relax();
    158	}
    159
    160	return halt_recv_msg.msg.data[0];
    161}
    162
    163/*
    164 * ATCA Support
    165 */
    166
    167#define IPMI_NETFN_ATCA			0x2c
    168#define IPMI_ATCA_SET_POWER_CMD		0x11
    169#define IPMI_ATCA_GET_ADDR_INFO_CMD	0x01
    170#define IPMI_PICMG_ID			0
    171
    172#define IPMI_NETFN_OEM				0x2e
    173#define IPMI_ATCA_PPS_GRACEFUL_RESTART		0x11
    174#define IPMI_ATCA_PPS_IANA			"\x00\x40\x0A"
    175#define IPMI_MOTOROLA_MANUFACTURER_ID		0x0000A1
    176#define IPMI_MOTOROLA_PPS_IPMC_PRODUCT_ID	0x0051
    177
    178static void (*atca_oem_poweroff_hook)(struct ipmi_user *user);
    179
    180static void pps_poweroff_atca(struct ipmi_user *user)
    181{
    182	struct ipmi_system_interface_addr smi_addr;
    183	struct kernel_ipmi_msg            send_msg;
    184	int                               rv;
    185	/*
    186	 * Configure IPMI address for local access
    187	 */
    188	smi_addr.addr_type = IPMI_SYSTEM_INTERFACE_ADDR_TYPE;
    189	smi_addr.channel = IPMI_BMC_CHANNEL;
    190	smi_addr.lun = 0;
    191
    192	pr_info("PPS powerdown hook used\n");
    193
    194	send_msg.netfn = IPMI_NETFN_OEM;
    195	send_msg.cmd = IPMI_ATCA_PPS_GRACEFUL_RESTART;
    196	send_msg.data = IPMI_ATCA_PPS_IANA;
    197	send_msg.data_len = 3;
    198	rv = ipmi_request_in_rc_mode(user,
    199				     (struct ipmi_addr *) &smi_addr,
    200				     &send_msg);
    201	if (rv && rv != IPMI_UNKNOWN_ERR_COMPLETION_CODE)
    202		pr_err("Unable to send ATCA, IPMI error 0x%x\n", rv);
    203
    204	return;
    205}
    206
    207static int ipmi_atca_detect(struct ipmi_user *user)
    208{
    209	struct ipmi_system_interface_addr smi_addr;
    210	struct kernel_ipmi_msg            send_msg;
    211	int                               rv;
    212	unsigned char                     data[1];
    213
    214	/*
    215	 * Configure IPMI address for local access
    216	 */
    217	smi_addr.addr_type = IPMI_SYSTEM_INTERFACE_ADDR_TYPE;
    218	smi_addr.channel = IPMI_BMC_CHANNEL;
    219	smi_addr.lun = 0;
    220
    221	/*
    222	 * Use get address info to check and see if we are ATCA
    223	 */
    224	send_msg.netfn = IPMI_NETFN_ATCA;
    225	send_msg.cmd = IPMI_ATCA_GET_ADDR_INFO_CMD;
    226	data[0] = IPMI_PICMG_ID;
    227	send_msg.data = data;
    228	send_msg.data_len = sizeof(data);
    229	rv = ipmi_request_wait_for_response(user,
    230					    (struct ipmi_addr *) &smi_addr,
    231					    &send_msg);
    232
    233	pr_info("ATCA Detect mfg 0x%X prod 0x%X\n", mfg_id, prod_id);
    234	if ((mfg_id == IPMI_MOTOROLA_MANUFACTURER_ID)
    235	    && (prod_id == IPMI_MOTOROLA_PPS_IPMC_PRODUCT_ID)) {
    236		pr_info("Installing Pigeon Point Systems Poweroff Hook\n");
    237		atca_oem_poweroff_hook = pps_poweroff_atca;
    238	}
    239	return !rv;
    240}
    241
    242static void ipmi_poweroff_atca(struct ipmi_user *user)
    243{
    244	struct ipmi_system_interface_addr smi_addr;
    245	struct kernel_ipmi_msg            send_msg;
    246	int                               rv;
    247	unsigned char                     data[4];
    248
    249	/*
    250	 * Configure IPMI address for local access
    251	 */
    252	smi_addr.addr_type = IPMI_SYSTEM_INTERFACE_ADDR_TYPE;
    253	smi_addr.channel = IPMI_BMC_CHANNEL;
    254	smi_addr.lun = 0;
    255
    256	pr_info("Powering down via ATCA power command\n");
    257
    258	/*
    259	 * Power down
    260	 */
    261	send_msg.netfn = IPMI_NETFN_ATCA;
    262	send_msg.cmd = IPMI_ATCA_SET_POWER_CMD;
    263	data[0] = IPMI_PICMG_ID;
    264	data[1] = 0; /* FRU id */
    265	data[2] = 0; /* Power Level */
    266	data[3] = 0; /* Don't change saved presets */
    267	send_msg.data = data;
    268	send_msg.data_len = sizeof(data);
    269	rv = ipmi_request_in_rc_mode(user,
    270				     (struct ipmi_addr *) &smi_addr,
    271				     &send_msg);
    272	/*
    273	 * At this point, the system may be shutting down, and most
    274	 * serial drivers (if used) will have interrupts turned off
    275	 * it may be better to ignore IPMI_UNKNOWN_ERR_COMPLETION_CODE
    276	 * return code
    277	 */
    278	if (rv && rv != IPMI_UNKNOWN_ERR_COMPLETION_CODE) {
    279		pr_err("Unable to send ATCA powerdown message, IPMI error 0x%x\n",
    280		       rv);
    281		goto out;
    282	}
    283
    284	if (atca_oem_poweroff_hook)
    285		atca_oem_poweroff_hook(user);
    286 out:
    287	return;
    288}
    289
    290/*
    291 * CPI1 Support
    292 */
    293
    294#define IPMI_NETFN_OEM_1				0xf8
    295#define OEM_GRP_CMD_SET_RESET_STATE		0x84
    296#define OEM_GRP_CMD_SET_POWER_STATE		0x82
    297#define IPMI_NETFN_OEM_8				0xf8
    298#define OEM_GRP_CMD_REQUEST_HOTSWAP_CTRL	0x80
    299#define OEM_GRP_CMD_GET_SLOT_GA			0xa3
    300#define IPMI_NETFN_SENSOR_EVT			0x10
    301#define IPMI_CMD_GET_EVENT_RECEIVER		0x01
    302
    303#define IPMI_CPI1_PRODUCT_ID		0x000157
    304#define IPMI_CPI1_MANUFACTURER_ID	0x0108
    305
    306static int ipmi_cpi1_detect(struct ipmi_user *user)
    307{
    308	return ((mfg_id == IPMI_CPI1_MANUFACTURER_ID)
    309		&& (prod_id == IPMI_CPI1_PRODUCT_ID));
    310}
    311
    312static void ipmi_poweroff_cpi1(struct ipmi_user *user)
    313{
    314	struct ipmi_system_interface_addr smi_addr;
    315	struct ipmi_ipmb_addr             ipmb_addr;
    316	struct kernel_ipmi_msg            send_msg;
    317	int                               rv;
    318	unsigned char                     data[1];
    319	int                               slot;
    320	unsigned char                     hotswap_ipmb;
    321	unsigned char                     aer_addr;
    322	unsigned char                     aer_lun;
    323
    324	/*
    325	 * Configure IPMI address for local access
    326	 */
    327	smi_addr.addr_type = IPMI_SYSTEM_INTERFACE_ADDR_TYPE;
    328	smi_addr.channel = IPMI_BMC_CHANNEL;
    329	smi_addr.lun = 0;
    330
    331	pr_info("Powering down via CPI1 power command\n");
    332
    333	/*
    334	 * Get IPMI ipmb address
    335	 */
    336	send_msg.netfn = IPMI_NETFN_OEM_8 >> 2;
    337	send_msg.cmd = OEM_GRP_CMD_GET_SLOT_GA;
    338	send_msg.data = NULL;
    339	send_msg.data_len = 0;
    340	rv = ipmi_request_in_rc_mode(user,
    341				     (struct ipmi_addr *) &smi_addr,
    342				     &send_msg);
    343	if (rv)
    344		goto out;
    345	slot = halt_recv_msg.msg.data[1];
    346	hotswap_ipmb = (slot > 9) ? (0xb0 + 2 * slot) : (0xae + 2 * slot);
    347
    348	/*
    349	 * Get active event receiver
    350	 */
    351	send_msg.netfn = IPMI_NETFN_SENSOR_EVT >> 2;
    352	send_msg.cmd = IPMI_CMD_GET_EVENT_RECEIVER;
    353	send_msg.data = NULL;
    354	send_msg.data_len = 0;
    355	rv = ipmi_request_in_rc_mode(user,
    356				     (struct ipmi_addr *) &smi_addr,
    357				     &send_msg);
    358	if (rv)
    359		goto out;
    360	aer_addr = halt_recv_msg.msg.data[1];
    361	aer_lun = halt_recv_msg.msg.data[2];
    362
    363	/*
    364	 * Setup IPMB address target instead of local target
    365	 */
    366	ipmb_addr.addr_type = IPMI_IPMB_ADDR_TYPE;
    367	ipmb_addr.channel = 0;
    368	ipmb_addr.slave_addr = aer_addr;
    369	ipmb_addr.lun = aer_lun;
    370
    371	/*
    372	 * Send request hotswap control to remove blade from dpv
    373	 */
    374	send_msg.netfn = IPMI_NETFN_OEM_8 >> 2;
    375	send_msg.cmd = OEM_GRP_CMD_REQUEST_HOTSWAP_CTRL;
    376	send_msg.data = &hotswap_ipmb;
    377	send_msg.data_len = 1;
    378	ipmi_request_in_rc_mode(user,
    379				(struct ipmi_addr *) &ipmb_addr,
    380				&send_msg);
    381
    382	/*
    383	 * Set reset asserted
    384	 */
    385	send_msg.netfn = IPMI_NETFN_OEM_1 >> 2;
    386	send_msg.cmd = OEM_GRP_CMD_SET_RESET_STATE;
    387	send_msg.data = data;
    388	data[0] = 1; /* Reset asserted state */
    389	send_msg.data_len = 1;
    390	rv = ipmi_request_in_rc_mode(user,
    391				     (struct ipmi_addr *) &smi_addr,
    392				     &send_msg);
    393	if (rv)
    394		goto out;
    395
    396	/*
    397	 * Power down
    398	 */
    399	send_msg.netfn = IPMI_NETFN_OEM_1 >> 2;
    400	send_msg.cmd = OEM_GRP_CMD_SET_POWER_STATE;
    401	send_msg.data = data;
    402	data[0] = 1; /* Power down state */
    403	send_msg.data_len = 1;
    404	rv = ipmi_request_in_rc_mode(user,
    405				     (struct ipmi_addr *) &smi_addr,
    406				     &send_msg);
    407	if (rv)
    408		goto out;
    409
    410 out:
    411	return;
    412}
    413
    414/*
    415 * ipmi_dell_chassis_detect()
    416 * Dell systems with IPMI < 1.5 don't set the chassis capability bit
    417 * but they can handle a chassis poweroff or powercycle command.
    418 */
    419
    420#define DELL_IANA_MFR_ID {0xA2, 0x02, 0x00}
    421static int ipmi_dell_chassis_detect(struct ipmi_user *user)
    422{
    423	const char ipmi_version_major = ipmi_version & 0xF;
    424	const char ipmi_version_minor = (ipmi_version >> 4) & 0xF;
    425	const char mfr[3] = DELL_IANA_MFR_ID;
    426	if (!memcmp(mfr, &mfg_id, sizeof(mfr)) &&
    427	    ipmi_version_major <= 1 &&
    428	    ipmi_version_minor < 5)
    429		return 1;
    430	return 0;
    431}
    432
    433/*
    434 * ipmi_hp_chassis_detect()
    435 * HP PA-RISC servers rp3410/rp3440, the C8000 workstation and the rx2600 and
    436 * zx6000 machines support IPMI vers 1 and don't set the chassis capability bit
    437 * but they can handle a chassis poweroff or powercycle command.
    438 */
    439
    440#define HP_IANA_MFR_ID 0x0b
    441#define HP_BMC_PROD_ID 0x8201
    442static int ipmi_hp_chassis_detect(struct ipmi_user *user)
    443{
    444	if (mfg_id == HP_IANA_MFR_ID
    445		&& prod_id == HP_BMC_PROD_ID
    446		&& ipmi_version == 1)
    447		return 1;
    448	return 0;
    449}
    450
    451/*
    452 * Standard chassis support
    453 */
    454
    455#define IPMI_NETFN_CHASSIS_REQUEST	0
    456#define IPMI_CHASSIS_CONTROL_CMD	0x02
    457
    458static int ipmi_chassis_detect(struct ipmi_user *user)
    459{
    460	/* Chassis support, use it. */
    461	return (capabilities & 0x80);
    462}
    463
    464static void ipmi_poweroff_chassis(struct ipmi_user *user)
    465{
    466	struct ipmi_system_interface_addr smi_addr;
    467	struct kernel_ipmi_msg            send_msg;
    468	int                               rv;
    469	unsigned char                     data[1];
    470
    471	/*
    472	 * Configure IPMI address for local access
    473	 */
    474	smi_addr.addr_type = IPMI_SYSTEM_INTERFACE_ADDR_TYPE;
    475	smi_addr.channel = IPMI_BMC_CHANNEL;
    476	smi_addr.lun = 0;
    477
    478 powercyclefailed:
    479	pr_info("Powering %s via IPMI chassis control command\n",
    480		(poweroff_powercycle ? "cycle" : "down"));
    481
    482	/*
    483	 * Power down
    484	 */
    485	send_msg.netfn = IPMI_NETFN_CHASSIS_REQUEST;
    486	send_msg.cmd = IPMI_CHASSIS_CONTROL_CMD;
    487	if (poweroff_powercycle)
    488		data[0] = IPMI_CHASSIS_POWER_CYCLE;
    489	else
    490		data[0] = IPMI_CHASSIS_POWER_DOWN;
    491	send_msg.data = data;
    492	send_msg.data_len = sizeof(data);
    493	rv = ipmi_request_in_rc_mode(user,
    494				     (struct ipmi_addr *) &smi_addr,
    495				     &send_msg);
    496	if (rv) {
    497		if (poweroff_powercycle) {
    498			/* power cycle failed, default to power down */
    499			pr_err("Unable to send chassis power cycle message, IPMI error 0x%x\n",
    500			       rv);
    501			poweroff_powercycle = 0;
    502			goto powercyclefailed;
    503		}
    504
    505		pr_err("Unable to send chassis power down message, IPMI error 0x%x\n",
    506		       rv);
    507	}
    508}
    509
    510
    511/* Table of possible power off functions. */
    512struct poweroff_function {
    513	char *platform_type;
    514	int  (*detect)(struct ipmi_user *user);
    515	void (*poweroff_func)(struct ipmi_user *user);
    516};
    517
    518static struct poweroff_function poweroff_functions[] = {
    519	{ .platform_type	= "ATCA",
    520	  .detect		= ipmi_atca_detect,
    521	  .poweroff_func	= ipmi_poweroff_atca },
    522	{ .platform_type	= "CPI1",
    523	  .detect		= ipmi_cpi1_detect,
    524	  .poweroff_func	= ipmi_poweroff_cpi1 },
    525	{ .platform_type	= "chassis",
    526	  .detect		= ipmi_dell_chassis_detect,
    527	  .poweroff_func	= ipmi_poweroff_chassis },
    528	{ .platform_type	= "chassis",
    529	  .detect		= ipmi_hp_chassis_detect,
    530	  .poweroff_func	= ipmi_poweroff_chassis },
    531	/* Chassis should generally be last, other things should override
    532	   it. */
    533	{ .platform_type	= "chassis",
    534	  .detect		= ipmi_chassis_detect,
    535	  .poweroff_func	= ipmi_poweroff_chassis },
    536};
    537#define NUM_PO_FUNCS ARRAY_SIZE(poweroff_functions)
    538
    539
    540/* Called on a powerdown request. */
    541static void ipmi_poweroff_function(void)
    542{
    543	if (!ready)
    544		return;
    545
    546	/* Use run-to-completion mode, since interrupts may be off. */
    547	specific_poweroff_func(ipmi_user);
    548}
    549
    550/* Wait for an IPMI interface to be installed, the first one installed
    551   will be grabbed by this code and used to perform the powerdown. */
    552static void ipmi_po_new_smi(int if_num, struct device *device)
    553{
    554	struct ipmi_system_interface_addr smi_addr;
    555	struct kernel_ipmi_msg            send_msg;
    556	int                               rv;
    557	int                               i;
    558
    559	if (ready)
    560		return;
    561
    562	if ((ifnum_to_use >= 0) && (ifnum_to_use != if_num))
    563		return;
    564
    565	rv = ipmi_create_user(if_num, &ipmi_poweroff_handler, NULL,
    566			      &ipmi_user);
    567	if (rv) {
    568		pr_err("could not create IPMI user, error %d\n", rv);
    569		return;
    570	}
    571
    572	ipmi_ifnum = if_num;
    573
    574	/*
    575	 * Do a get device ide and store some results, since this is
    576	 * used by several functions.
    577	 */
    578	smi_addr.addr_type = IPMI_SYSTEM_INTERFACE_ADDR_TYPE;
    579	smi_addr.channel = IPMI_BMC_CHANNEL;
    580	smi_addr.lun = 0;
    581
    582	send_msg.netfn = IPMI_NETFN_APP_REQUEST;
    583	send_msg.cmd = IPMI_GET_DEVICE_ID_CMD;
    584	send_msg.data = NULL;
    585	send_msg.data_len = 0;
    586	rv = ipmi_request_wait_for_response(ipmi_user,
    587					    (struct ipmi_addr *) &smi_addr,
    588					    &send_msg);
    589	if (rv) {
    590		pr_err("Unable to send IPMI get device id info, IPMI error 0x%x\n",
    591		       rv);
    592		goto out_err;
    593	}
    594
    595	if (halt_recv_msg.msg.data_len < 12) {
    596		pr_err("(chassis) IPMI get device id info too short, was %d bytes, needed %d bytes\n",
    597		       halt_recv_msg.msg.data_len, 12);
    598		goto out_err;
    599	}
    600
    601	mfg_id = (halt_recv_msg.msg.data[7]
    602		  | (halt_recv_msg.msg.data[8] << 8)
    603		  | (halt_recv_msg.msg.data[9] << 16));
    604	prod_id = (halt_recv_msg.msg.data[10]
    605		   | (halt_recv_msg.msg.data[11] << 8));
    606	capabilities = halt_recv_msg.msg.data[6];
    607	ipmi_version = halt_recv_msg.msg.data[5];
    608
    609
    610	/* Scan for a poweroff method */
    611	for (i = 0; i < NUM_PO_FUNCS; i++) {
    612		if (poweroff_functions[i].detect(ipmi_user))
    613			goto found;
    614	}
    615
    616 out_err:
    617	pr_err("Unable to find a poweroff function that will work, giving up\n");
    618	ipmi_destroy_user(ipmi_user);
    619	return;
    620
    621 found:
    622	pr_info("Found a %s style poweroff function\n",
    623		poweroff_functions[i].platform_type);
    624	specific_poweroff_func = poweroff_functions[i].poweroff_func;
    625	old_poweroff_func = pm_power_off;
    626	pm_power_off = ipmi_poweroff_function;
    627	ready = 1;
    628}
    629
    630static void ipmi_po_smi_gone(int if_num)
    631{
    632	if (!ready)
    633		return;
    634
    635	if (ipmi_ifnum != if_num)
    636		return;
    637
    638	ready = 0;
    639	ipmi_destroy_user(ipmi_user);
    640	pm_power_off = old_poweroff_func;
    641}
    642
    643static struct ipmi_smi_watcher smi_watcher = {
    644	.owner    = THIS_MODULE,
    645	.new_smi  = ipmi_po_new_smi,
    646	.smi_gone = ipmi_po_smi_gone
    647};
    648
    649
    650#ifdef CONFIG_PROC_FS
    651#include <linux/sysctl.h>
    652
    653static struct ctl_table ipmi_table[] = {
    654	{ .procname	= "poweroff_powercycle",
    655	  .data		= &poweroff_powercycle,
    656	  .maxlen	= sizeof(poweroff_powercycle),
    657	  .mode		= 0644,
    658	  .proc_handler	= proc_dointvec },
    659	{ }
    660};
    661
    662static struct ctl_table ipmi_dir_table[] = {
    663	{ .procname	= "ipmi",
    664	  .mode		= 0555,
    665	  .child	= ipmi_table },
    666	{ }
    667};
    668
    669static struct ctl_table ipmi_root_table[] = {
    670	{ .procname	= "dev",
    671	  .mode		= 0555,
    672	  .child	= ipmi_dir_table },
    673	{ }
    674};
    675
    676static struct ctl_table_header *ipmi_table_header;
    677#endif /* CONFIG_PROC_FS */
    678
    679/*
    680 * Startup and shutdown functions.
    681 */
    682static int __init ipmi_poweroff_init(void)
    683{
    684	int rv;
    685
    686	pr_info("Copyright (C) 2004 MontaVista Software - IPMI Powerdown via sys_reboot\n");
    687
    688	if (poweroff_powercycle)
    689		pr_info("Power cycle is enabled\n");
    690
    691#ifdef CONFIG_PROC_FS
    692	ipmi_table_header = register_sysctl_table(ipmi_root_table);
    693	if (!ipmi_table_header) {
    694		pr_err("Unable to register powercycle sysctl\n");
    695		rv = -ENOMEM;
    696		goto out_err;
    697	}
    698#endif
    699
    700	rv = ipmi_smi_watcher_register(&smi_watcher);
    701
    702#ifdef CONFIG_PROC_FS
    703	if (rv) {
    704		unregister_sysctl_table(ipmi_table_header);
    705		pr_err("Unable to register SMI watcher: %d\n", rv);
    706		goto out_err;
    707	}
    708
    709 out_err:
    710#endif
    711	return rv;
    712}
    713
    714#ifdef MODULE
    715static void __exit ipmi_poweroff_cleanup(void)
    716{
    717	int rv;
    718
    719#ifdef CONFIG_PROC_FS
    720	unregister_sysctl_table(ipmi_table_header);
    721#endif
    722
    723	ipmi_smi_watcher_unregister(&smi_watcher);
    724
    725	if (ready) {
    726		rv = ipmi_destroy_user(ipmi_user);
    727		if (rv)
    728			pr_err("could not cleanup the IPMI user: 0x%x\n", rv);
    729		pm_power_off = old_poweroff_func;
    730	}
    731}
    732module_exit(ipmi_poweroff_cleanup);
    733#endif
    734
    735module_init(ipmi_poweroff_init);
    736MODULE_LICENSE("GPL");
    737MODULE_AUTHOR("Corey Minyard <minyard@mvista.com>");
    738MODULE_DESCRIPTION("IPMI Poweroff extension to sys_reboot");