diff options
Diffstat (limited to 'drivers/firmware/dcdbas.c')
| -rw-r--r-- | drivers/firmware/dcdbas.c | 596 |
1 files changed, 596 insertions, 0 deletions
diff --git a/drivers/firmware/dcdbas.c b/drivers/firmware/dcdbas.c new file mode 100644 index 0000000..955537f --- /dev/null +++ b/drivers/firmware/dcdbas.c @@ -0,0 +1,596 @@ +/* + * 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) 1995-2005 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/device.h> +#include <linux/dma-mapping.h> +#include <linux/errno.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 <asm/io.h> +#include <asm/semaphore.h> + +#include "dcdbas.h" + +#define DRIVER_NAME "dcdbas" +#define DRIVER_VERSION "5.6.0-1" +#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 DECLARE_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", + __FUNCTION__, 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", + __FUNCTION__, 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", + __FUNCTION__, 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 */ + down(&smi_data_lock); + ret = smi_data_buf_realloc(buf_size); + up(&smi_data_lock); + if (ret) + return ret; + + return count; +} + +static ssize_t smi_data_read(struct kobject *kobj, char *buf, loff_t pos, + size_t count) +{ + size_t max_read; + ssize_t ret; + + down(&smi_data_lock); + + if (pos >= smi_data_buf_size) { + ret = 0; + goto out; + } + + max_read = smi_data_buf_size - pos; + ret = min(max_read, count); + memcpy(buf, smi_data_buf + pos, ret); +out: + up(&smi_data_lock); + return ret; +} + +static ssize_t smi_data_write(struct kobject *kobj, char *buf, loff_t pos, + size_t count) +{ + ssize_t ret; + + down(&smi_data_lock); + + ret = smi_data_buf_realloc(pos + count); + if (ret) + goto out; + + memcpy(smi_data_buf + pos, buf, count); + ret = count; +out: + up(&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 */ + down(&smi_data_lock); + ret = smi_data_buf_realloc(sizeof(struct apm_cmd)); + up(&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; +} + +/** + * smi_request: generate SMI request + * + * Called with smi_data_lock. + */ +static int smi_request(struct smi_cmd *smi_cmd) +{ + cpumask_t old_mask; + int ret = 0; + + if (smi_cmd->magic != SMI_CMD_MAGIC) { + dev_info(&dcdbas_pdev->dev, "%s: invalid magic value\n", + __FUNCTION__); + return -EBADR; + } + + /* SMI requires CPU 0 */ + old_mask = current->cpus_allowed; + set_cpus_allowed(current, cpumask_of_cpu(0)); + if (smp_processor_id() != 0) { + dev_dbg(&dcdbas_pdev->dev, "%s: failed to get CPU 0\n", + __FUNCTION__); + ret = -EBUSY; + goto out; + } + + /* generate SMI */ + asm volatile ( + "outb %b0,%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(current, 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; + + down(&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 = 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 = 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: + up(&smi_data_lock); + return ret; +} + +/** + * 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", + __FUNCTION__, 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", __FUNCTION__); + return; + } + + if (smi_data_buf_size < sizeof(struct apm_cmd)) { + dev_dbg(&dcdbas_pdev->dev, "%s: SMI buffer too small\n", + __FUNCTION__); + 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) +{ + static unsigned int notify_cnt = 0; + + 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 */ + if (++notify_cnt == 2) { + printk(KERN_WARNING + "Please wait for shutdown " + "action to complete...\n"); + dcdbas_host_control(); + } + /* + * register again and initiate the host control + * action on the second notification to allow + * everyone that registered to be notified + */ + register_reboot_notifier(nb); + } + break; + } + + return NOTIFY_DONE; +} + +static struct notifier_block dcdbas_reboot_nb = { + .notifier_call = dcdbas_reboot_notify, + .next = NULL, + .priority = 0 +}; + +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 device_attribute *dcdbas_dev_attrs[] = { + &dev_attr_smi_data_buf_size, + &dev_attr_smi_data_buf_phys_addr, + &dev_attr_smi_request, + &dev_attr_host_control_action, + &dev_attr_host_control_smi_type, + &dev_attr_host_control_on_shutdown, + NULL +}; + +/** + * dcdbas_init: initialize driver + */ +static int __init dcdbas_init(void) +{ + int i; + + host_control_action = HC_ACTION_NONE; + host_control_smi_type = HC_SMITYPE_NONE; + + dcdbas_pdev = platform_device_register_simple(DRIVER_NAME, -1, NULL, 0); + if (IS_ERR(dcdbas_pdev)) + return PTR_ERR(dcdbas_pdev); + + /* + * BIOS SMI calls require buffer addresses be in 32-bit address space. + * This is done by setting the DMA mask below. + */ + dcdbas_pdev->dev.coherent_dma_mask = DMA_32BIT_MASK; + dcdbas_pdev->dev.dma_mask = &dcdbas_pdev->dev.coherent_dma_mask; + + register_reboot_notifier(&dcdbas_reboot_nb); + + for (i = 0; dcdbas_bin_attrs[i]; i++) + sysfs_create_bin_file(&dcdbas_pdev->dev.kobj, + dcdbas_bin_attrs[i]); + + for (i = 0; dcdbas_dev_attrs[i]; i++) + device_create_file(&dcdbas_pdev->dev, dcdbas_dev_attrs[i]); + + dev_info(&dcdbas_pdev->dev, "%s (version %s)\n", + DRIVER_DESCRIPTION, DRIVER_VERSION); + + return 0; +} + +/** + * dcdbas_exit: perform driver cleanup + */ +static void __exit dcdbas_exit(void) +{ + platform_device_unregister(dcdbas_pdev); + unregister_reboot_notifier(&dcdbas_reboot_nb); + smi_data_buf_free(); +} + +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"); + |
