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authorThomas Gleixner <tglx@linutronix.de>2010-10-23 11:28:42 +0200
committerIngo Molnar <mingo@elte.hu>2010-10-27 17:22:16 +0200
commit8654b1c2de1465120974899fc1c8aa00e91d4b7e (patch)
tree2bfe8cd3cb0caadf8be0bdf6574690e476173f75 /arch/x86/platform/olpc/olpc.c
parent329b84e42e3ee348b114fd0bfe4b2421e6139257 (diff)
downloadlinux-linaro-stable-8654b1c2de1465120974899fc1c8aa00e91d4b7e.tar.gz
x86: Move olpc to platform
Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andres Salomon <dilinger@queued.net>
Diffstat (limited to 'arch/x86/platform/olpc/olpc.c')
-rw-r--r--arch/x86/platform/olpc/olpc.c281
1 files changed, 281 insertions, 0 deletions
diff --git a/arch/x86/platform/olpc/olpc.c b/arch/x86/platform/olpc/olpc.c
new file mode 100644
index 000000000000..edaf3fe8dc5e
--- /dev/null
+++ b/arch/x86/platform/olpc/olpc.c
@@ -0,0 +1,281 @@
+/*
+ * 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 <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);
+
+/* 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++) {
+ if (wait_on_ibf(0x6c, 0)) {
+ printk(KERN_ERR "olpc-ec: timeout waiting for"
+ " EC accept data!\n");
+ goto err;
+ }
+ pr_devel("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");
+ 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);
+
+static bool __init check_ofw_architecture(void)
+{
+ size_t propsize;
+ char olpc_arch[5];
+ const void *args[] = { NULL, "architecture", olpc_arch, (void *)5 };
+ void *res[] = { &propsize };
+
+ if (olpc_ofw("getprop", args, res)) {
+ printk(KERN_ERR "ofw: getprop call failed!\n");
+ return false;
+ }
+ return propsize == 5 && strncmp("OLPC", olpc_arch, 5) == 0;
+}
+
+static u32 __init get_board_revision(void)
+{
+ size_t propsize;
+ __be32 rev;
+ const void *args[] = { NULL, "board-revision-int", &rev, (void *)4 };
+ void *res[] = { &propsize };
+
+ if (olpc_ofw("getprop", args, res) || propsize != 4) {
+ printk(KERN_ERR "ofw: getprop call failed!\n");
+ return cpu_to_be32(0);
+ }
+ return be32_to_cpu(rev);
+}
+
+static bool __init platform_detect(void)
+{
+ if (!check_ofw_architecture())
+ return false;
+ olpc_platform_info.flags |= OLPC_F_PRESENT;
+ olpc_platform_info.boardrev = get_board_revision();
+ return true;
+}
+
+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 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
+
+ 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;
+ }
+
+ return 0;
+}
+
+postcore_initcall(olpc_init);