/* * dcdbas.c: Dell Systems Management Base Driver * * The Dell Systems Management Base Driver provides a sysfs interface for * systems management software to perform System Management Interrupts (SMIs) * and Host Control Actions (power cycle or power off after OS shutdown) on * Dell systems. * * See Documentation/dcdbas.txt for more information. * * Copyright (C) 1995-2006 Dell Inc. * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License v2.0 as published by * the Free Software Foundation. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. */ #include <linux/platform_device.h> #include <linux/dma-mapping.h> #include <linux/errno.h> #include <linux/gfp.h> #include <linux/init.h> #include <linux/kernel.h> #include <linux/mc146818rtc.h> #include <linux/module.h> #include <linux/reboot.h> #include <linux/sched.h> #include <linux/smp.h> #include <linux/spinlock.h> #include <linux/string.h> #include <linux/types.h> #include <linux/mutex.h> #include <asm/io.h> #include "dcdbas.h" #define DRIVER_NAME "dcdbas" #define DRIVER_VERSION "5.6.0-3.2" #define DRIVER_DESCRIPTION "Dell Systems Management Base Driver" static struct platform_device *dcdbas_pdev; static u8 *smi_data_buf; static dma_addr_t smi_data_buf_handle; static unsigned long smi_data_buf_size; static u32 smi_data_buf_phys_addr; static DEFINE_MUTEX(smi_data_lock); static unsigned int host_control_action; static unsigned int host_control_smi_type; static unsigned int host_control_on_shutdown; /** * smi_data_buf_free: free SMI data buffer */ static void smi_data_buf_free(void) { if (!smi_data_buf) return; dev_dbg(&dcdbas_pdev->dev, "%s: phys: %x size: %lu\n", __func__, smi_data_buf_phys_addr, smi_data_buf_size); dma_free_coherent(&dcdbas_pdev->dev, smi_data_buf_size, smi_data_buf, smi_data_buf_handle); smi_data_buf = NULL; smi_data_buf_handle = 0; smi_data_buf_phys_addr = 0; smi_data_buf_size = 0; } /** * smi_data_buf_realloc: grow SMI data buffer if needed */ static int smi_data_buf_realloc(unsigned long size) { void *buf; dma_addr_t handle; if (smi_data_buf_size >= size) return 0; if (size > MAX_SMI_DATA_BUF_SIZE) return -EINVAL; /* new buffer is needed */ buf = dma_alloc_coherent(&dcdbas_pdev->dev, size, &handle, GFP_KERNEL); if (!buf) { dev_dbg(&dcdbas_pdev->dev, "%s: failed to allocate memory size %lu\n", __func__, size); return -ENOMEM; } /* memory zeroed by dma_alloc_coherent */ if (smi_data_buf) memcpy(buf, smi_data_buf, smi_data_buf_size); /* free any existing buffer */ smi_data_buf_free(); /* set up new buffer for use */ smi_data_buf = buf; smi_data_buf_handle = handle; smi_data_buf_phys_addr = (u32) virt_to_phys(buf); smi_data_buf_size = size; dev_dbg(&dcdbas_pdev->dev, "%s: phys: %x size: %lu\n", __func__, smi_data_buf_phys_addr, smi_data_buf_size); return 0; } static ssize_t smi_data_buf_phys_addr_show(struct device *dev, struct device_attribute *attr, char *buf) { return sprintf(buf, "%x\n", smi_data_buf_phys_addr); } static ssize_t smi_data_buf_size_show(struct device *dev, struct device_attribute *attr, char *buf) { return sprintf(buf, "%lu\n", smi_data_buf_size); } static ssize_t smi_data_buf_size_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) { unsigned long buf_size; ssize_t ret; buf_size = simple_strtoul(buf, NULL, 10); /* make sure SMI data buffer is at least buf_size */ mutex_lock(&smi_data_lock); ret = smi_data_buf_realloc(buf_size); mutex_unlock(&smi_data_lock); if (ret) return ret; return count; } static ssize_t smi_data_read(struct file *filp, struct kobject *kobj, struct bin_attribute *bin_attr, char *buf, loff_t pos, size_t count) { ssize_t ret; mutex_lock(&smi_data_lock); ret = memory_read_from_buffer(buf, count, &pos, smi_data_buf, smi_data_buf_size); mutex_unlock(&smi_data_lock); return ret; } static ssize_t smi_data_write(struct file *filp, struct kobject *kobj, struct bin_attribute *bin_attr, char *buf, loff_t pos, size_t count) { ssize_t ret; if ((pos + count) > MAX_SMI_DATA_BUF_SIZE) return -EINVAL; mutex_lock(&smi_data_lock); ret = smi_data_buf_realloc(pos + count); if (ret) goto out; memcpy(smi_data_buf + pos, buf, count); ret = count; out: mutex_unlock(&smi_data_lock); return ret; } static ssize_t host_control_action_show(struct device *dev, struct device_attribute *attr, char *buf) { return sprintf(buf, "%u\n", host_control_action); } static ssize_t host_control_action_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) { ssize_t ret; /* make sure buffer is available for host control command */ mutex_lock(&smi_data_lock); ret = smi_data_buf_realloc(sizeof(struct apm_cmd)); mutex_unlock(&smi_data_lock); if (ret) return ret; host_control_action = simple_strtoul(buf, NULL, 10); return count; } static ssize_t host_control_smi_type_show(struct device *dev, struct device_attribute *attr, char *buf) { return sprintf(buf, "%u\n", host_control_smi_type); } static ssize_t host_control_smi_type_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) { host_control_smi_type = simple_strtoul(buf, NULL, 10); return count; } static ssize_t host_control_on_shutdown_show(struct device *dev, struct device_attribute *attr, char *buf) { return sprintf(buf, "%u\n", host_control_on_shutdown); } static ssize_t host_control_on_shutdown_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) { host_control_on_shutdown = simple_strtoul(buf, NULL, 10); return count; } /** * dcdbas_smi_request: generate SMI request * * Called with smi_data_lock. */ int dcdbas_smi_request(struct smi_cmd *smi_cmd) { cpumask_var_t old_mask; int ret = 0; if (smi_cmd->magic != SMI_CMD_MAGIC) { dev_info(&dcdbas_pdev->dev, "%s: invalid magic value\n", __func__); return -EBADR; } /* SMI requires CPU 0 */ if (!alloc_cpumask_var(&old_mask, GFP_KERNEL)) return -ENOMEM; cpumask_copy(old_mask, ¤t->cpus_allowed); set_cpus_allowed_ptr(current, cpumask_of(0)); if (smp_processor_id() != 0) { dev_dbg(&dcdbas_pdev->dev, "%s: failed to get CPU 0\n", __func__); ret = -EBUSY; goto out; } /* generate SMI */ /* inb to force posted write through and make SMI happen now */ asm volatile ( "outb %b0,%w1\n" "inb %w1" : /* no output args */ : "a" (smi_cmd->command_code), "d" (smi_cmd->command_address), "b" (smi_cmd->ebx), "c" (smi_cmd->ecx) : "memory" ); out: set_cpus_allowed_ptr(current, old_mask); free_cpumask_var(old_mask); return ret; } /** * smi_request_store: * * The valid values are: * 0: zero SMI data buffer * 1: generate calling interface SMI * 2: generate raw SMI * * User application writes smi_cmd to smi_data before telling driver * to generate SMI. */ static ssize_t smi_request_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) { struct smi_cmd *smi_cmd; unsigned long val = simple_strtoul(buf, NULL, 10); ssize_t ret; mutex_lock(&smi_data_lock); if (smi_data_buf_size < sizeof(struct smi_cmd)) { ret = -ENODEV; goto out; } smi_cmd = (struct smi_cmd *)smi_data_buf; switch (val) { case 2: /* Raw SMI */ ret = dcdbas_smi_request(smi_cmd); if (!ret) ret = count; break; case 1: /* Calling Interface SMI */ smi_cmd->ebx = (u32) virt_to_phys(smi_cmd->command_buffer); ret = dcdbas_smi_request(smi_cmd); if (!ret) ret = count; break; case 0: memset(smi_data_buf, 0, smi_data_buf_size); ret = count; break; default: ret = -EINVAL; break; } out: mutex_unlock(&smi_data_lock); return ret; } EXPORT_SYMBOL(dcdbas_smi_request); /** * host_control_smi: generate host control SMI * * Caller must set up the host control command in smi_data_buf. */ static int host_control_smi(void) { struct apm_cmd *apm_cmd; u8 *data; unsigned long flags; u32 num_ticks; s8 cmd_status; u8 index; apm_cmd = (struct apm_cmd *)smi_data_buf; apm_cmd->status = ESM_STATUS_CMD_UNSUCCESSFUL; switch (host_control_smi_type) { case HC_SMITYPE_TYPE1: spin_lock_irqsave(&rtc_lock, flags); /* write SMI data buffer physical address */ data = (u8 *)&smi_data_buf_phys_addr; for (index = PE1300_CMOS_CMD_STRUCT_PTR; index < (PE1300_CMOS_CMD_STRUCT_PTR + 4); index++, data++) { outb(index, (CMOS_BASE_PORT + CMOS_PAGE2_INDEX_PORT_PIIX4)); outb(*data, (CMOS_BASE_PORT + CMOS_PAGE2_DATA_PORT_PIIX4)); } /* first set status to -1 as called by spec */ cmd_status = ESM_STATUS_CMD_UNSUCCESSFUL; outb((u8) cmd_status, PCAT_APM_STATUS_PORT); /* generate SMM call */ outb(ESM_APM_CMD, PCAT_APM_CONTROL_PORT); spin_unlock_irqrestore(&rtc_lock, flags); /* wait a few to see if it executed */ num_ticks = TIMEOUT_USEC_SHORT_SEMA_BLOCKING; while ((cmd_status = inb(PCAT_APM_STATUS_PORT)) == ESM_STATUS_CMD_UNSUCCESSFUL) { num_ticks--; if (num_ticks == EXPIRED_TIMER) return -ETIME; } break; case HC_SMITYPE_TYPE2: case HC_SMITYPE_TYPE3: spin_lock_irqsave(&rtc_lock, flags); /* write SMI data buffer physical address */ data = (u8 *)&smi_data_buf_phys_addr; for (index = PE1400_CMOS_CMD_STRUCT_PTR; index < (PE1400_CMOS_CMD_STRUCT_PTR + 4); index++, data++) { outb(index, (CMOS_BASE_PORT + CMOS_PAGE1_INDEX_PORT)); outb(*data, (CMOS_BASE_PORT + CMOS_PAGE1_DATA_PORT)); } /* generate SMM call */ if (host_control_smi_type == HC_SMITYPE_TYPE3) outb(ESM_APM_CMD, PCAT_APM_CONTROL_PORT); else outb(ESM_APM_CMD, PE1400_APM_CONTROL_PORT); /* restore RTC index pointer since it was written to above */ CMOS_READ(RTC_REG_C); spin_unlock_irqrestore(&rtc_lock, flags); /* read control port back to serialize write */ cmd_status = inb(PE1400_APM_CONTROL_PORT); /* wait a few to see if it executed */ num_ticks = TIMEOUT_USEC_SHORT_SEMA_BLOCKING; while (apm_cmd->status == ESM_STATUS_CMD_UNSUCCESSFUL) { num_ticks--; if (num_ticks == EXPIRED_TIMER) return -ETIME; } break; default: dev_dbg(&dcdbas_pdev->dev, "%s: invalid SMI type %u\n", __func__, host_control_smi_type); return -ENOSYS; } return 0; } /** * dcdbas_host_control: initiate host control * * This function is called by the driver after the system has * finished shutting down if the user application specified a * host control action to perform on shutdown. It is safe to * use smi_data_buf at this point because the system has finished * shutting down and no userspace apps are running. */ static void dcdbas_host_control(void) { struct apm_cmd *apm_cmd; u8 action; if (host_control_action == HC_ACTION_NONE) return; action = host_control_action; host_control_action = HC_ACTION_NONE; if (!smi_data_buf) { dev_dbg(&dcdbas_pdev->dev, "%s: no SMI buffer\n", __func__); return; } if (smi_data_buf_size < sizeof(struct apm_cmd)) { dev_dbg(&dcdbas_pdev->dev, "%s: SMI buffer too small\n", __func__); return; } apm_cmd = (struct apm_cmd *)smi_data_buf; /* power off takes precedence */ if (action & HC_ACTION_HOST_CONTROL_POWEROFF) { apm_cmd->command = ESM_APM_POWER_CYCLE; apm_cmd->reserved = 0; *((s16 *)&apm_cmd->parameters.shortreq.parm[0]) = (s16) 0; host_control_smi(); } else if (action & HC_ACTION_HOST_CONTROL_POWERCYCLE) { apm_cmd->command = ESM_APM_POWER_CYCLE; apm_cmd->reserved = 0; *((s16 *)&apm_cmd->parameters.shortreq.parm[0]) = (s16) 20; host_control_smi(); } } /** * dcdbas_reboot_notify: handle reboot notification for host control */ static int dcdbas_reboot_notify(struct notifier_block *nb, unsigned long code, void *unused) { switch (code) { case SYS_DOWN: case SYS_HALT: case SYS_POWER_OFF: if (host_control_on_shutdown) { /* firmware is going to perform host control action */ printk(KERN_WARNING "Please wait for shutdown " "action to complete...\n"); dcdbas_host_control(); } break; } return NOTIFY_DONE; } static struct notifier_block dcdbas_reboot_nb = { .notifier_call = dcdbas_reboot_notify, .next = NULL, .priority = INT_MIN }; static DCDBAS_BIN_ATTR_RW(smi_data); static struct bin_attribute *dcdbas_bin_attrs[] = { &bin_attr_smi_data, NULL }; static DCDBAS_DEV_ATTR_RW(smi_data_buf_size); static DCDBAS_DEV_ATTR_RO(smi_data_buf_phys_addr); static DCDBAS_DEV_ATTR_WO(smi_request); static DCDBAS_DEV_ATTR_RW(host_control_action); static DCDBAS_DEV_ATTR_RW(host_control_smi_type); static DCDBAS_DEV_ATTR_RW(host_control_on_shutdown); static struct attribute *dcdbas_dev_attrs[] = { &dev_attr_smi_data_buf_size.attr, &dev_attr_smi_data_buf_phys_addr.attr, &dev_attr_smi_request.attr, &dev_attr_host_control_action.attr, &dev_attr_host_control_smi_type.attr, &dev_attr_host_control_on_shutdown.attr, NULL }; static struct attribute_group dcdbas_attr_group = { .attrs = dcdbas_dev_attrs, .bin_attrs = dcdbas_bin_attrs, }; static int dcdbas_probe(struct platform_device *dev) { int error; host_control_action = HC_ACTION_NONE; host_control_smi_type = HC_SMITYPE_NONE; dcdbas_pdev = dev; /* * BIOS SMI calls require buffer addresses be in 32-bit address space. * This is done by setting the DMA mask below. */ error = dma_set_coherent_mask(&dcdbas_pdev->dev, DMA_BIT_MASK(32)); if (error) return error; error = sysfs_create_group(&dev->dev.kobj, &dcdbas_attr_group); if (error) return error; register_reboot_notifier(&dcdbas_reboot_nb); dev_info(&dev->dev, "%s (version %s)\n", DRIVER_DESCRIPTION, DRIVER_VERSION); return 0; } static int dcdbas_remove(struct platform_device *dev) { unregister_reboot_notifier(&dcdbas_reboot_nb); sysfs_remove_group(&dev->dev.kobj, &dcdbas_attr_group); return 0; } static struct platform_driver dcdbas_driver = { .driver = { .name = DRIVER_NAME, }, .probe = dcdbas_probe, .remove = dcdbas_remove, }; static const struct platform_device_info dcdbas_dev_info __initconst = { .name = DRIVER_NAME, .id = -1, .dma_mask = DMA_BIT_MASK(32), }; static struct platform_device *dcdbas_pdev_reg; /** * dcdbas_init: initialize driver */ static int __init dcdbas_init(void) { int error; error = platform_driver_register(&dcdbas_driver); if (error) return error; dcdbas_pdev_reg = platform_device_register_full(&dcdbas_dev_info); if (IS_ERR(dcdbas_pdev_reg)) { error = PTR_ERR(dcdbas_pdev_reg); goto err_unregister_driver; } return 0; err_unregister_driver: platform_driver_unregister(&dcdbas_driver); return error; } /** * dcdbas_exit: perform driver cleanup */ static void __exit dcdbas_exit(void) { /* * make sure functions that use dcdbas_pdev are called * before platform_device_unregister */ unregister_reboot_notifier(&dcdbas_reboot_nb); /* * We have to free the buffer here instead of dcdbas_remove * because only in module exit function we can be sure that * all sysfs attributes belonging to this module have been * released. */ if (dcdbas_pdev) smi_data_buf_free(); platform_device_unregister(dcdbas_pdev_reg); platform_driver_unregister(&dcdbas_driver); } module_init(dcdbas_init); module_exit(dcdbas_exit); MODULE_DESCRIPTION(DRIVER_DESCRIPTION " (version " DRIVER_VERSION ")"); MODULE_VERSION(DRIVER_VERSION); MODULE_AUTHOR("Dell Inc."); MODULE_LICENSE("GPL"); /* Any System or BIOS claiming to be by Dell */ MODULE_ALIAS("dmi:*:[bs]vnD[Ee][Ll][Ll]*:*");