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Diffstat (limited to 'target/linux/olpc/files/arch/i386/kernel/olpc.c')
-rw-r--r--target/linux/olpc/files/arch/i386/kernel/olpc.c320
1 files changed, 320 insertions, 0 deletions
diff --git a/target/linux/olpc/files/arch/i386/kernel/olpc.c b/target/linux/olpc/files/arch/i386/kernel/olpc.c
new file mode 100644
index 0000000000..d540cb0eae
--- /dev/null
+++ b/target/linux/olpc/files/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);