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Diffstat (limited to 'arch/x86/kernel/mfgpt_32.c')
-rw-r--r--arch/x86/kernel/mfgpt_32.c410
1 files changed, 0 insertions, 410 deletions
diff --git a/arch/x86/kernel/mfgpt_32.c b/arch/x86/kernel/mfgpt_32.c
deleted file mode 100644
index 2a62d843f01..00000000000
--- a/arch/x86/kernel/mfgpt_32.c
+++ /dev/null
@@ -1,410 +0,0 @@
-/*
- * Driver/API for AMD Geode Multi-Function General Purpose Timers (MFGPT)
- *
- * Copyright (C) 2006, Advanced Micro Devices, Inc.
- * Copyright (C) 2007, Andres Salomon <dilinger@debian.org>
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of version 2 of the GNU General Public License
- * as published by the Free Software Foundation.
- *
- * The MFGPTs are documented in AMD Geode CS5536 Companion Device Data Book.
- */
-
-/*
- * We are using the 32.768kHz input clock - it's the only one that has the
- * ranges we find desirable. The following table lists the suitable
- * divisors and the associated Hz, minimum interval and the maximum interval:
- *
- * Divisor Hz Min Delta (s) Max Delta (s)
- * 1 32768 .00048828125 2.000
- * 2 16384 .0009765625 4.000
- * 4 8192 .001953125 8.000
- * 8 4096 .00390625 16.000
- * 16 2048 .0078125 32.000
- * 32 1024 .015625 64.000
- * 64 512 .03125 128.000
- * 128 256 .0625 256.000
- * 256 128 .125 512.000
- */
-
-#include <linux/kernel.h>
-#include <linux/interrupt.h>
-#include <linux/module.h>
-#include <asm/geode.h>
-
-#define MFGPT_DEFAULT_IRQ 7
-
-static struct mfgpt_timer_t {
- unsigned int avail:1;
-} mfgpt_timers[MFGPT_MAX_TIMERS];
-
-/* Selected from the table above */
-
-#define MFGPT_DIVISOR 16
-#define MFGPT_SCALE 4 /* divisor = 2^(scale) */
-#define MFGPT_HZ (32768 / MFGPT_DIVISOR)
-#define MFGPT_PERIODIC (MFGPT_HZ / HZ)
-
-/* Allow for disabling of MFGPTs */
-static int disable;
-static int __init mfgpt_disable(char *s)
-{
- disable = 1;
- return 1;
-}
-__setup("nomfgpt", mfgpt_disable);
-
-/* Reset the MFGPT timers. This is required by some broken BIOSes which already
- * do the same and leave the system in an unstable state. TinyBIOS 0.98 is
- * affected at least (0.99 is OK with MFGPT workaround left to off).
- */
-static int __init mfgpt_fix(char *s)
-{
- u32 val, dummy;
-
- /* The following udocumented bit resets the MFGPT timers */
- val = 0xFF; dummy = 0;
- wrmsr(MSR_MFGPT_SETUP, val, dummy);
- return 1;
-}
-__setup("mfgptfix", mfgpt_fix);
-
-/*
- * Check whether any MFGPTs are available for the kernel to use. In most
- * cases, firmware that uses AMD's VSA code will claim all timers during
- * bootup; we certainly don't want to take them if they're already in use.
- * In other cases (such as with VSAless OpenFirmware), the system firmware
- * leaves timers available for us to use.
- */
-
-
-static int timers = -1;
-
-static void geode_mfgpt_detect(void)
-{
- int i;
- u16 val;
-
- timers = 0;
-
- if (disable) {
- printk(KERN_INFO "geode-mfgpt: MFGPT support is disabled\n");
- goto done;
- }
-
- if (!geode_get_dev_base(GEODE_DEV_MFGPT)) {
- printk(KERN_INFO "geode-mfgpt: MFGPT LBAR is not set up\n");
- goto done;
- }
-
- for (i = 0; i < MFGPT_MAX_TIMERS; i++) {
- val = geode_mfgpt_read(i, MFGPT_REG_SETUP);
- if (!(val & MFGPT_SETUP_SETUP)) {
- mfgpt_timers[i].avail = 1;
- timers++;
- }
- }
-
-done:
- printk(KERN_INFO "geode-mfgpt: %d MFGPT timers available.\n", timers);
-}
-
-int geode_mfgpt_toggle_event(int timer, int cmp, int event, int enable)
-{
- u32 msr, mask, value, dummy;
- int shift = (cmp == MFGPT_CMP1) ? 0 : 8;
-
- if (timer < 0 || timer >= MFGPT_MAX_TIMERS)
- return -EIO;
-
- /*
- * The register maps for these are described in sections 6.17.1.x of
- * the AMD Geode CS5536 Companion Device Data Book.
- */
- switch (event) {
- case MFGPT_EVENT_RESET:
- /*
- * XXX: According to the docs, we cannot reset timers above
- * 6; that is, resets for 7 and 8 will be ignored. Is this
- * a problem? -dilinger
- */
- msr = MSR_MFGPT_NR;
- mask = 1 << (timer + 24);
- break;
-
- case MFGPT_EVENT_NMI:
- msr = MSR_MFGPT_NR;
- mask = 1 << (timer + shift);
- break;
-
- case MFGPT_EVENT_IRQ:
- msr = MSR_MFGPT_IRQ;
- mask = 1 << (timer + shift);
- break;
-
- default:
- return -EIO;
- }
-
- rdmsr(msr, value, dummy);
-
- if (enable)
- value |= mask;
- else
- value &= ~mask;
-
- wrmsr(msr, value, dummy);
- return 0;
-}
-EXPORT_SYMBOL_GPL(geode_mfgpt_toggle_event);
-
-int geode_mfgpt_set_irq(int timer, int cmp, int *irq, int enable)
-{
- u32 zsel, lpc, dummy;
- int shift;
-
- if (timer < 0 || timer >= MFGPT_MAX_TIMERS)
- return -EIO;
-
- /*
- * Unfortunately, MFGPTs come in pairs sharing their IRQ lines. If VSA
- * is using the same CMP of the timer's Siamese twin, the IRQ is set to
- * 2, and we mustn't use nor change it.
- * XXX: Likewise, 2 Linux drivers might clash if the 2nd overwrites the
- * IRQ of the 1st. This can only happen if forcing an IRQ, calling this
- * with *irq==0 is safe. Currently there _are_ no 2 drivers.
- */
- rdmsr(MSR_PIC_ZSEL_LOW, zsel, dummy);
- shift = ((cmp == MFGPT_CMP1 ? 0 : 4) + timer % 4) * 4;
- if (((zsel >> shift) & 0xF) == 2)
- return -EIO;
-
- /* Choose IRQ: if none supplied, keep IRQ already set or use default */
- if (!*irq)
- *irq = (zsel >> shift) & 0xF;
- if (!*irq)
- *irq = MFGPT_DEFAULT_IRQ;
-
- /* Can't use IRQ if it's 0 (=disabled), 2, or routed to LPC */
- if (*irq < 1 || *irq == 2 || *irq > 15)
- return -EIO;
- rdmsr(MSR_PIC_IRQM_LPC, lpc, dummy);
- if (lpc & (1 << *irq))
- return -EIO;
-
- /* All chosen and checked - go for it */
- if (geode_mfgpt_toggle_event(timer, cmp, MFGPT_EVENT_IRQ, enable))
- return -EIO;
- if (enable) {
- zsel = (zsel & ~(0xF << shift)) | (*irq << shift);
- wrmsr(MSR_PIC_ZSEL_LOW, zsel, dummy);
- }
-
- return 0;
-}
-
-static int mfgpt_get(int timer)
-{
- mfgpt_timers[timer].avail = 0;
- printk(KERN_INFO "geode-mfgpt: Registered timer %d\n", timer);
- return timer;
-}
-
-int geode_mfgpt_alloc_timer(int timer, int domain)
-{
- int i;
-
- if (timers == -1) {
- /* timers haven't been detected yet */
- geode_mfgpt_detect();
- }
-
- if (!timers)
- return -1;
-
- if (timer >= MFGPT_MAX_TIMERS)
- return -1;
-
- if (timer < 0) {
- /* Try to find an available timer */
- for (i = 0; i < MFGPT_MAX_TIMERS; i++) {
- if (mfgpt_timers[i].avail)
- return mfgpt_get(i);
-
- if (i == 5 && domain == MFGPT_DOMAIN_WORKING)
- break;
- }
- } else {
- /* If they requested a specific timer, try to honor that */
- if (mfgpt_timers[timer].avail)
- return mfgpt_get(timer);
- }
-
- /* No timers available - too bad */
- return -1;
-}
-EXPORT_SYMBOL_GPL(geode_mfgpt_alloc_timer);
-
-
-#ifdef CONFIG_GEODE_MFGPT_TIMER
-
-/*
- * The MFPGT timers on the CS5536 provide us with suitable timers to use
- * as clock event sources - not as good as a HPET or APIC, but certainly
- * better than the PIT. This isn't a general purpose MFGPT driver, but
- * a simplified one designed specifically to act as a clock event source.
- * For full details about the MFGPT, please consult the CS5536 data sheet.
- */
-
-#include <linux/clocksource.h>
-#include <linux/clockchips.h>
-
-static unsigned int mfgpt_tick_mode = CLOCK_EVT_MODE_SHUTDOWN;
-static u16 mfgpt_event_clock;
-
-static int irq;
-static int __init mfgpt_setup(char *str)
-{
- get_option(&str, &irq);
- return 1;
-}
-__setup("mfgpt_irq=", mfgpt_setup);
-
-static void mfgpt_disable_timer(u16 clock)
-{
- /* avoid races by clearing CMP1 and CMP2 unconditionally */
- geode_mfgpt_write(clock, MFGPT_REG_SETUP, (u16) ~MFGPT_SETUP_CNTEN |
- MFGPT_SETUP_CMP1 | MFGPT_SETUP_CMP2);
-}
-
-static int mfgpt_next_event(unsigned long, struct clock_event_device *);
-static void mfgpt_set_mode(enum clock_event_mode, struct clock_event_device *);
-
-static struct clock_event_device mfgpt_clockevent = {
- .name = "mfgpt-timer",
- .features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT,
- .set_mode = mfgpt_set_mode,
- .set_next_event = mfgpt_next_event,
- .rating = 250,
- .cpumask = cpu_all_mask,
- .shift = 32
-};
-
-static void mfgpt_start_timer(u16 delta)
-{
- geode_mfgpt_write(mfgpt_event_clock, MFGPT_REG_CMP2, (u16) delta);
- geode_mfgpt_write(mfgpt_event_clock, MFGPT_REG_COUNTER, 0);
-
- geode_mfgpt_write(mfgpt_event_clock, MFGPT_REG_SETUP,
- MFGPT_SETUP_CNTEN | MFGPT_SETUP_CMP2);
-}
-
-static void mfgpt_set_mode(enum clock_event_mode mode,
- struct clock_event_device *evt)
-{
- mfgpt_disable_timer(mfgpt_event_clock);
-
- if (mode == CLOCK_EVT_MODE_PERIODIC)
- mfgpt_start_timer(MFGPT_PERIODIC);
-
- mfgpt_tick_mode = mode;
-}
-
-static int mfgpt_next_event(unsigned long delta, struct clock_event_device *evt)
-{
- mfgpt_start_timer(delta);
- return 0;
-}
-
-static irqreturn_t mfgpt_tick(int irq, void *dev_id)
-{
- u16 val = geode_mfgpt_read(mfgpt_event_clock, MFGPT_REG_SETUP);
-
- /* See if the interrupt was for us */
- if (!(val & (MFGPT_SETUP_SETUP | MFGPT_SETUP_CMP2 | MFGPT_SETUP_CMP1)))
- return IRQ_NONE;
-
- /* Turn off the clock (and clear the event) */
- mfgpt_disable_timer(mfgpt_event_clock);
-
- if (mfgpt_tick_mode == CLOCK_EVT_MODE_SHUTDOWN)
- return IRQ_HANDLED;
-
- /* Clear the counter */
- geode_mfgpt_write(mfgpt_event_clock, MFGPT_REG_COUNTER, 0);
-
- /* Restart the clock in periodic mode */
-
- if (mfgpt_tick_mode == CLOCK_EVT_MODE_PERIODIC) {
- geode_mfgpt_write(mfgpt_event_clock, MFGPT_REG_SETUP,
- MFGPT_SETUP_CNTEN | MFGPT_SETUP_CMP2);
- }
-
- mfgpt_clockevent.event_handler(&mfgpt_clockevent);
- return IRQ_HANDLED;
-}
-
-static struct irqaction mfgptirq = {
- .handler = mfgpt_tick,
- .flags = IRQF_DISABLED | IRQF_NOBALANCING | IRQF_TIMER,
- .name = "mfgpt-timer"
-};
-
-int __init mfgpt_timer_setup(void)
-{
- int timer, ret;
- u16 val;
-
- timer = geode_mfgpt_alloc_timer(MFGPT_TIMER_ANY, MFGPT_DOMAIN_WORKING);
- if (timer < 0) {
- printk(KERN_ERR
- "mfgpt-timer: Could not allocate a MFPGT timer\n");
- return -ENODEV;
- }
-
- mfgpt_event_clock = timer;
-
- /* Set up the IRQ on the MFGPT side */
- if (geode_mfgpt_setup_irq(mfgpt_event_clock, MFGPT_CMP2, &irq)) {
- printk(KERN_ERR "mfgpt-timer: Could not set up IRQ %d\n", irq);
- return -EIO;
- }
-
- /* And register it with the kernel */
- ret = setup_irq(irq, &mfgptirq);
-
- if (ret) {
- printk(KERN_ERR
- "mfgpt-timer: Unable to set up the interrupt.\n");
- goto err;
- }
-
- /* Set the clock scale and enable the event mode for CMP2 */
- val = MFGPT_SCALE | (3 << 8);
-
- geode_mfgpt_write(mfgpt_event_clock, MFGPT_REG_SETUP, val);
-
- /* Set up the clock event */
- mfgpt_clockevent.mult = div_sc(MFGPT_HZ, NSEC_PER_SEC,
- mfgpt_clockevent.shift);
- mfgpt_clockevent.min_delta_ns = clockevent_delta2ns(0xF,
- &mfgpt_clockevent);
- mfgpt_clockevent.max_delta_ns = clockevent_delta2ns(0xFFFE,
- &mfgpt_clockevent);
-
- printk(KERN_INFO
- "mfgpt-timer: Registering MFGPT timer %d as a clock event, using IRQ %d\n",
- timer, irq);
- clockevents_register_device(&mfgpt_clockevent);
-
- return 0;
-
-err:
- geode_mfgpt_release_irq(mfgpt_event_clock, MFGPT_CMP2, &irq);
- printk(KERN_ERR
- "mfgpt-timer: Unable to set up the MFGPT clock source\n");
- return -EIO;
-}
-
-#endif
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