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author | Thomas Gleixner <tglx@linutronix.de> | 2010-02-17 18:27:37 +0100 |
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committer | Thomas Gleixner <tglx@linutronix.de> | 2010-02-17 18:28:05 +0100 |
commit | b7e56edba4b02f2079042c326a8cd72a44635817 (patch) | |
tree | b5042002e9747cd8fb1278d61f86d8b92a74c018 /arch/x86/kernel/mfgpt_32.c | |
parent | 13ca0fcaa33f6b1984c4111b6ec5df42689fea6f (diff) | |
parent | b0483e78e5c4c9871fc5541875b3bc006846d46b (diff) | |
download | talos-op-linux-b7e56edba4b02f2079042c326a8cd72a44635817.tar.gz talos-op-linux-b7e56edba4b02f2079042c326a8cd72a44635817.zip |
Merge branch 'linus' into x86/mm
x86/mm is on 32-rc4 and missing the spinlock namespace changes which
are needed for further commits into this topic.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Diffstat (limited to 'arch/x86/kernel/mfgpt_32.c')
-rw-r--r-- | arch/x86/kernel/mfgpt_32.c | 410 |
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 2a62d843f015..000000000000 --- 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 |