diff options
Diffstat (limited to 'target/linux/olpc/files-2.6.23/arch/i386/kernel/olpc.c')
| -rw-r--r-- | target/linux/olpc/files-2.6.23/arch/i386/kernel/olpc.c | 320 |
1 files changed, 320 insertions, 0 deletions
diff --git a/target/linux/olpc/files-2.6.23/arch/i386/kernel/olpc.c b/target/linux/olpc/files-2.6.23/arch/i386/kernel/olpc.c new file mode 100644 index 0000000000..d540cb0eae --- /dev/null +++ b/target/linux/olpc/files-2.6.23/arch/i386/kernel/olpc.c @@ -0,0 +1,320 @@ +/* Support for the OLPC DCON and OLPC EC access + * Copyright (C) 2006, Advanced Micro Devices, Inc. + * + * 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/autoconf.h> +#include <linux/kernel.h> +#include <linux/init.h> +#include <linux/mc146818rtc.h> +#include <linux/delay.h> +#include <linux/spinlock.h> + +#include <asm/olpc.h> +#include <asm/ofw.h> + +/* This is our new multi-purpose structure used to contain the + * information about the platform that we detect + */ + +struct olpc_platform_t olpc_platform_info; +EXPORT_SYMBOL_GPL(olpc_platform_info); + +/********************************************************************* + * EC locking and access + *********************************************************************/ + +static DEFINE_SPINLOCK(ec_lock); + +/* 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 *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: waited %u ms for IBF (%d)!\n", + EC_BASE_TIMEOUT-timeo, line); + } + + 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: waited %u ms for OBF (%d)!\n", + EC_BASE_TIMEOUT-timeo, line); + } + + return !(state == desired); +} + +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; + + spin_lock_irqsave(&ec_lock, flags); + + 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.. + */ + printk(KERN_DEBUG "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++) { + if (wait_on_ibf(0x6c, 0)) { + printk(KERN_ERR "olpc-ec: timeout waiting for" + " EC accept data!\n"); + goto err; + } + printk(KERN_DEBUG "olpc-ec: sending cmd arg 0x%x\n", + inbuf[i]); + outb(inbuf[i], 0x68); + } + } + 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"); + goto restart; + } + outbuf[i] = inb(0x68); + printk(KERN_DEBUG "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); + +/********************************************************************* + * DCON stuff + *********************************************************************/ + +static void olpc_power_off(void) +{ + printk(KERN_INFO "OLPC power off sequence...\n"); + outb(0xff, 0x381); + outb(0x14, 0x382); + outb(0x01, 0x383); + outb(0xff, 0x381); + outb(0x14, 0x382); + outb(0x00, 0x383); +} + +static void __init +ec_detect(void) +{ + olpc_ec_cmd(0x08, NULL, 0, (unsigned char *) &olpc_platform_info.ecver, 1); +} + +/* Check to see if this version of the OLPC board has VSA built + * in, and set a flag + */ + +static void __init vsa_detect(void) +{ + u16 rev; + + outw(0xFC53, 0xAC1C); + outw(0x0003, 0xAC1C); + + rev = inw(0xAC1E); + + if (rev == 0x4132) + olpc_platform_info.flags |= OLPC_F_VSA; +} + +/* Map OFW revisions to what OLPC_REV_* */ +static const char __initdata *olpc_boardrev_str[] = { + "A1", + "preB1", + "B1", + "preB2", + "B2", + "preB3", + "B3", + "B4", + "C1", + "R1", +}; + +static void __init platform_detect(char *revision, size_t len) +{ + size_t propsize; + int i; + + BUG_ON(ARRAY_SIZE(olpc_boardrev_str) != OLPC_REV_UNKNOWN); + + if (ofw("getprop", 4, 1, NULL, "model", revision, len, &propsize)) { + printk(KERN_ERR "ofw: getprop call failed!\n"); + goto failed; + } + if (len < propsize) { + printk(KERN_ERR "ofw: revision string is too long!\n"); + goto failed; + } + + for (i=0; i < ARRAY_SIZE(olpc_boardrev_str); i++) { + if (strcmp(revision, olpc_boardrev_str[i]) == 0) { + olpc_platform_info.boardrev = i; + return; + } + } + +failed: + strncpy(revision, "Unknown", len); + olpc_platform_info.boardrev = OLPC_REV_UNKNOWN; +} + +static int olpc_dcon_present = -1; +module_param(olpc_dcon_present, int, 0444); + +/* REV_A CMOS map: + * bit 440; DCON present bit + */ + +#define OLPC_CMOS_DCON_OFFSET (440 / 8) +#define OLPC_CMOS_DCON_MASK 0x01 + +static int __init olpc_init(void) +{ + unsigned char *romsig; + char revision[10]; + + spin_lock_init(&ec_lock); + + romsig = ioremap(0xffffffc0, 16); + + if (!romsig) + return 0; + + if (strncmp(romsig, "CL1 Q", 7)) + goto unmap; + if (strncmp(romsig+6, romsig+13, 3)) { + printk(KERN_INFO "OLPC BIOS signature looks invalid. Assuming not OLPC\n"); + goto unmap; + } + printk(KERN_INFO "OLPC board with OpenFirmware: %.16s\n", romsig); + + olpc_platform_info.flags |= OLPC_F_PRESENT; + + pm_power_off = olpc_power_off; + + /* Get the platform revision */ + platform_detect(revision, sizeof(revision)); + + /* If olpc_dcon_present isn't set by the command line, then + * "detect" it + */ + + if (olpc_dcon_present == -1) { + /* B1 and greater always has a DCON */ + if (olpc_platform_info.boardrev >= OLPC_REV_B1 && + olpc_platform_info.boardrev < OLPC_REV_UNKNOWN) + olpc_dcon_present = 1; + } + + if (olpc_dcon_present) + olpc_platform_info.flags |= OLPC_F_DCON; + + /* Get the EC revision */ + ec_detect(); + + /* Check to see if the VSA exists */ + vsa_detect(); + + printk(KERN_INFO "OLPC board revision: %s (EC=%x)\n", revision, + olpc_platform_info.ecver); + + unmap: + iounmap(romsig); + + return 0; +} + +postcore_initcall(olpc_init); |