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Diffstat (limited to 'drivers/firmware/dcdbas.c')
-rw-r--r--drivers/firmware/dcdbas.c596
1 files changed, 596 insertions, 0 deletions
diff --git a/drivers/firmware/dcdbas.c b/drivers/firmware/dcdbas.c
new file mode 100644
index 000000000000..955537fe9958
--- /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");
+
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-21 10:51:09 +0100