- 根目录:
- arch
- x86
- platform
- olpc
- olpc.c
/*
* Support for the OLPC DCON and OLPC EC access
*
* Copyright © 2006 Advanced Micro Devices, Inc.
* Copyright © 2007-2008 Andres Salomon <dilinger@debian.org>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*/
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/delay.h>
#include <linux/spinlock.h>
#include <linux/io.h>
#include <linux/string.h>
#include <linux/platform_device.h>
#include <linux/of.h>
#include <linux/syscore_ops.h>
#include <linux/debugfs.h>
#include <linux/mutex.h>
#include <asm/geode.h>
#include <asm/setup.h>
#include <asm/olpc.h>
#include <asm/olpc_ofw.h>
struct olpc_platform_t olpc_platform_info;
EXPORT_SYMBOL_GPL(olpc_platform_info);
static DEFINE_SPINLOCK(ec_lock);
/* debugfs interface to EC commands */
#define EC_MAX_CMD_ARGS (5 + 1) /* cmd byte + 5 args */
#define EC_MAX_CMD_REPLY (8)
static struct dentry *ec_debugfs_dir;
static DEFINE_MUTEX(ec_debugfs_cmd_lock);
static unsigned char ec_debugfs_resp[EC_MAX_CMD_REPLY];
static unsigned int ec_debugfs_resp_bytes;
/* EC event mask to be applied during suspend (defining wakeup sources). */
static u16 ec_wakeup_mask;
/* what the timeout *should* be (in ms) */
#define EC_BASE_TIMEOUT 20
/* the timeout that bugs in the EC might force us to actually use */
static int ec_timeout = EC_BASE_TIMEOUT;
static int __init olpc_ec_timeout_set(char *str)
{
if (get_option(&str, &ec_timeout) != 1) {
ec_timeout = EC_BASE_TIMEOUT;
printk(KERN_ERR "olpc-ec: invalid argument to "
"'olpc_ec_timeout=', ignoring!\n");
}
printk(KERN_DEBUG "olpc-ec: using %d ms delay for EC commands.\n",
ec_timeout);
return 1;
}
__setup("olpc_ec_timeout=", olpc_ec_timeout_set);
/*
* These {i,o}bf_status functions return whether the buffers are full or not.
*/
static inline unsigned int ibf_status(unsigned int port)
{
return !!(inb(port) & 0x02);
}
static inline unsigned int obf_status(unsigned int port)
{
return inb(port) & 0x01;
}
#define wait_on_ibf(p, d) __wait_on_ibf(__LINE__, (p), (d))
static int __wait_on_ibf(unsigned int line, unsigned int port, int desired)
{
unsigned int timeo;
int state = ibf_status(port);
for (timeo = ec_timeout; state != desired && timeo; timeo--) {
mdelay(1);
state = ibf_status(port);
}
if ((state == desired) && (ec_timeout > EC_BASE_TIMEOUT) &&
timeo < (ec_timeout - EC_BASE_TIMEOUT)) {
printk(KERN_WARNING "olpc-ec: %d: waited %u ms for IBF!\n",
line, ec_timeout - timeo);
}
return !(state == desired);
}
#define wait_on_obf(p, d) __wait_on_obf(__LINE__, (p), (d))
static int __wait_on_obf(unsigned int line, unsigned int port, int desired)
{
unsigned int timeo;
int state = obf_status(port);
for (timeo = ec_timeout; state != desired && timeo; timeo--) {
mdelay(1);
state = obf_status(port);
}
if ((state == desired) && (ec_timeout > EC_BASE_TIMEOUT) &&
timeo < (ec_timeout - EC_BASE_TIMEOUT)) {
printk(KERN_WARNING "olpc-ec: %d: waited %u ms for OBF!\n",
line, ec_timeout - timeo);
}
return !(state == desired);
}
/*
* This allows the kernel to run Embedded Controller commands. The EC is
* documented at <http://wiki.laptop.org/go/Embedded_controller>, and the
* available EC commands are here:
* <http://wiki.laptop.org/go/Ec_specification>. Unfortunately, while
* OpenFirmware's source is available, the EC's is not.
*/
int olpc_ec_cmd(unsigned char cmd, unsigned char *inbuf, size_t inlen,
unsigned char *outbuf, size_t outlen)
{
unsigned long flags;
int ret = -EIO;
int i;
int restarts = 0;
spin_lock_irqsave(&ec_lock, flags);
/* Clear OBF */
for (i = 0; i < 10 && (obf_status(0x6c) == 1); i++)
inb(0x68);
if (i == 10) {
printk(KERN_ERR "olpc-ec: timeout while attempting to "
"clear OBF flag!\n");
goto err;
}
if (wait_on_ibf(0x6c, 0)) {
printk(KERN_ERR "olpc-ec: timeout waiting for EC to "
"quiesce!\n");
goto err;
}
restart:
/*
* Note that if we time out during any IBF checks, that's a failure;
* we have to return. There's no way for the kernel to clear that.
*
* If we time out during an OBF check, we can restart the command;
* reissuing it will clear the OBF flag, and we should be alright.
* The OBF flag will sometimes misbehave due to what we believe
* is a hardware quirk..
*/
pr_devel("olpc-ec: running cmd 0x%x\n", cmd);
outb(cmd, 0x6c);
if (wait_on_ibf(0x6c, 0)) {
printk(KERN_ERR "olpc-ec: timeout waiting for EC to read "
"command!\n");
goto err;
}
if (inbuf && inlen) {
/* write data to EC */
for (i = 0; i < inlen; i++) {
pr_devel("olpc-ec: sending cmd arg 0x%x\n", inbuf[i]);
outb(inbuf[i], 0x68);
if (wait_on_ibf(0x6c, 0)) {
printk(KERN_ERR "olpc-ec: timeout waiting for"
" EC accept data!\n");
goto err;
}
}
}
if (outbuf && outlen) {
/* read data from EC */
for (i = 0; i < outlen; i++) {
if (wait_on_obf(0x6c, 1)) {
printk(KERN_ERR "olpc-ec: timeout waiting for"
" EC to provide data!\n");
if (restarts++ < 10)
goto restart;
goto err;
}
outbuf[i] = inb(0x68);
pr_devel("olpc-ec: received 0x%x\n", outbuf[i]);
}
}
ret = 0;
err:
spin_unlock_irqrestore(&ec_lock, flags);
return ret;
}
EXPORT_SYMBOL_GPL(olpc_ec_cmd);
void olpc_ec_wakeup_set(u16 value)
{
ec_wakeup_mask |= value;
}
EXPORT_SYMBOL_GPL(olpc_ec_wakeup_set);
void olpc_ec_wakeup_clear(u16 value)
{
ec_wakeup_mask &= ~value;
}
EXPORT_SYMBOL_GPL(olpc_ec_wakeup_clear);
/*
* Returns true if the compile and runtime configurations allow for EC events
* to wake the system.
*/
bool olpc_ec_wakeup_available(void)
{
if (!machine_is_olpc())
return false;
/*
* XO-1 EC wakeups are available when olpc-xo1-sci driver is
* compiled in
*/
#ifdef CONFIG_OLPC_XO1_SCI
if (olpc_platform_info.boardrev < olpc_board_pre(0xd0)) /* XO-1 */
return true;
#endif
/*
* XO-1.5 EC wakeups are available when olpc-xo15-sci driver is
* compiled in
*/
#ifdef CONFIG_OLPC_XO15_SCI
if (olpc_platform_info.boardrev >= olpc_board_pre(0xd0)) /* XO-1.5 */
return true;
#endif
return false;
}
EXPORT_SYMBOL_GPL(olpc_ec_wakeup_available);
int olpc_ec_mask_write(u16 bits)
{
if (olpc_platform_info.flags & OLPC_F_EC_WIDE_SCI) {
__be16 ec_word = cpu_to_be16(bits);
return olpc_ec_cmd(EC_WRITE_EXT_SCI_MASK, (void *) &ec_word, 2,
NULL, 0);
} else {
unsigned char ec_byte = bits & 0xff;
return olpc_ec_cmd(EC_WRITE_SCI_MASK, &ec_byte, 1, NULL, 0);
}
}
EXPORT_SYMBOL_GPL(olpc_ec_mask_write);
int olpc_ec_sci_query(u16 *sci_value)
{
int ret;
if (olpc_platform_info.flags & OLPC_F_EC_WIDE_SCI) {
__be16 ec_word;
ret = olpc_ec_cmd(EC_EXT_SCI_QUERY,
NULL, 0, (void *) &ec_word, 2);
if (ret == 0)
*sci_value = be16_to_cpu(ec_word);
} else {
unsigned char ec_byte;
ret = olpc_ec_cmd(EC_SCI_QUERY, NULL, 0, &ec_byte, 1);
if (ret == 0)
*sci_value = ec_byte;
}
return ret;
}
EXPORT_SYMBOL_GPL(olpc_ec_sci_query);
static ssize_t ec_debugfs_cmd_write(struct file *file, const char __user *buf,
size_t size, loff_t *ppos)
{
int i, m;
unsigned char ec_cmd[EC_MAX_CMD_ARGS];
unsigned int ec_cmd_int[EC_MAX_CMD_ARGS];
char cmdbuf[64];
int ec_cmd_bytes;
mutex_lock(&ec_debugfs_cmd_lock);
size = simple_write_to_buffer(cmdbuf, sizeof(cmdbuf), ppos, buf, size);
m = sscanf(cmdbuf, "%x:%u %x %x %x %x %x", &ec_cmd_int[0],
&ec_debugfs_resp_bytes,
&ec_cmd_int[1], &ec_cmd_int[2], &ec_cmd_int[3],
&ec_cmd_int[4], &ec_cmd_int[5]);
if (m < 2 || ec_debugfs_resp_bytes > EC_MAX_CMD_REPLY) {
/* reset to prevent overflow on read */
ec_debugfs_resp_bytes = 0;
printk(KERN_DEBUG "olpc-ec: bad ec cmd: "
"cmd:response-count [arg1 [arg2 ...]]\n");
size = -EINVAL;
goto out;
}
/* convert scanf'd ints to char */
ec_cmd_bytes = m - 2;
for (i = 0; i <= ec_cmd_bytes; i++)
ec_cmd[i] = ec_cmd_int[i];
printk(KERN_DEBUG "olpc-ec: debugfs cmd 0x%02x with %d args "
"%02x %02x %02x %02x %02x, want %d returns\n",
ec_cmd[0], ec_cmd_bytes, ec_cmd[1], ec_cmd[2], ec_cmd[3],
ec_cmd[4], ec_cmd[5], ec_debugfs_resp_bytes);
olpc_ec_cmd(ec_cmd[0], (ec_cmd_bytes == 0) ? NULL : &ec_cmd[1],
ec_cmd_bytes, ec_debugfs_resp, ec_debugfs_resp_bytes);
printk(KERN_DEBUG "olpc-ec: response "
"%02x %02x %02x %02x %02x %02x %02x %02x (%d bytes expected)\n",
ec_debugfs_resp[0], ec_debugfs_resp[1], ec_debugfs_resp[2],
ec_debugfs_resp[3], ec_debugfs_resp[4], ec_debugfs_resp[5],
ec_debugfs_resp[6], ec_debugfs_resp[7], ec_debugfs_resp_bytes);
out:
mutex_unlock(&ec_debugfs_cmd_lock);
return size;
}
static ssize_t ec_debugfs_cmd_read(struct file *file, char __user *buf,
size_t size, loff_t *ppos)
{
unsigned int i, r;
char *rp;
char respbuf[64];
mutex_lock(&ec_debugfs_cmd_lock);
rp = respbuf;
rp += sprintf(rp, "%02x", ec_debugfs_resp[0]);
for (i = 1; i < ec_debugfs_resp_bytes; i++)
rp += sprintf(rp, ", %02x", ec_debugfs_resp[i]);
mutex_unlock(&ec_debugfs_cmd_lock);
rp += sprintf(rp, "\n");
r = rp - respbuf;
return simple_read_from_buffer(buf, size, ppos, respbuf, r);
}
static const struct file_operations ec_debugfs_genops = {
.write = ec_debugfs_cmd_write,
.read = ec_debugfs_cmd_read,
};
static void setup_debugfs(void)
{
ec_debugfs_dir = debugfs_create_dir("olpc-ec", 0);
if (ec_debugfs_dir == ERR_PTR(-ENODEV))
return;
debugfs_create_file("cmd", 0600, ec_debugfs_dir, NULL,
&ec_debugfs_genops);
}
static int olpc_ec_suspend(void)
{
return olpc_ec_mask_write(ec_wakeup_mask);
}
static bool __init check_ofw_architecture(struct device_node *root)
{
const char *olpc_arch;
int propsize;
olpc_arch = of_get_property(root, "architecture", &propsize);
return propsize == 5 && strncmp("OLPC", olpc_arch, 5) == 0;
}
static u32 __init get_board_revision(struct device_node *root)
{
int propsize;
const __be32 *rev;
rev = of_get_property(root, "board-revision-int", &propsize);
if (propsize != 4)
return 0;
return be32_to_cpu(*rev);
}
static bool __init platform_detect(void)
{
struct device_node *root = of_find_node_by_path("/");
bool success;
if (!root)
return false;
success = check_ofw_architecture(root);
if (success) {
olpc_platform_info.boardrev = get_board_revision(root);
olpc_platform_info.flags |= OLPC_F_PRESENT;
}
of_node_put(root);
return success;
}
static int __init add_xo1_platform_devices(void)
{
struct platform_device *pdev;
pdev = platform_device_register_simple("xo1-rfkill", -1, NULL, 0);
if (IS_ERR(pdev))
return PTR_ERR(pdev);
pdev = platform_device_register_simple("olpc-xo1", -1, NULL, 0);
if (IS_ERR(pdev))
return PTR_ERR(pdev);
return 0;
}
static struct syscore_ops olpc_syscore_ops = {
.suspend = olpc_ec_suspend,
};
static int __init olpc_init(void)
{
int r = 0;
if (!olpc_ofw_present() || !platform_detect())
return 0;
spin_lock_init(&ec_lock);
/* assume B1 and above models always have a DCON */
if (olpc_board_at_least(olpc_board(0xb1)))
olpc_platform_info.flags |= OLPC_F_DCON;
/* get the EC revision */
olpc_ec_cmd(EC_FIRMWARE_REV, NULL, 0,
(unsigned char *) &olpc_platform_info.ecver, 1);
#ifdef CONFIG_PCI_OLPC
/* If the VSA exists let it emulate PCI, if not emulate in kernel.
* XO-1 only. */
if (olpc_platform_info.boardrev < olpc_board_pre(0xd0) &&
!cs5535_has_vsa2())
x86_init.pci.arch_init = pci_olpc_init;
#endif
/* EC version 0x5f adds support for wide SCI mask */
if (olpc_platform_info.ecver >= 0x5f)
olpc_platform_info.flags |= OLPC_F_EC_WIDE_SCI;
printk(KERN_INFO "OLPC board revision %s%X (EC=%x)\n",
((olpc_platform_info.boardrev & 0xf) < 8) ? "pre" : "",
olpc_platform_info.boardrev >> 4,
olpc_platform_info.ecver);
if (olpc_platform_info.boardrev < olpc_board_pre(0xd0)) { /* XO-1 */
r = add_xo1_platform_devices();
if (r)
return r;
}
register_syscore_ops(&olpc_syscore_ops);
setup_debugfs();
return 0;
}
postcore_initcall(olpc_init);