#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];
#define MFGPT_HZ (32768 / MFGPT_DIVISOR)
#define MFGPT_PERIODIC (MFGPT_HZ / HZ)
-#ifdef CONFIG_GEODE_MFGPT_TIMER
-static int __init mfgpt_timer_setup(void);
-#else
-#define mfgpt_timer_setup() (0)
-#endif
-
/* Allow for disabling of MFGPTs */
static int disable;
static int __init mfgpt_disable(char *s)
/* The following udocumented bit resets the MFGPT timers */
val = 0xFF; dummy = 0;
- wrmsr(0x5140002B, val, dummy);
+ wrmsr(MSR_MFGPT_SETUP, val, dummy);
return 1;
}
__setup("mfgptfix", mfgpt_fix);
* In other cases (such as with VSAless OpenFirmware), the system firmware
* leaves timers available for us to use.
*/
-int __init geode_mfgpt_detect(void)
+
+
+static int timers = -1;
+
+static void geode_mfgpt_detect(void)
{
- int count = 0, i;
+ int i;
u16 val;
+ timers = 0;
+
if (disable) {
- printk(KERN_INFO "geode-mfgpt: Skipping MFGPT setup\n");
- return 0;
+ 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;
- count++;
+ timers++;
}
}
- /* set up clock event device, if desired */
- i = mfgpt_timer_setup();
-
- return count;
+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)
* 6; that is, resets for 7 and 8 will be ignored. Is this
* a problem? -dilinger
*/
- msr = MFGPT_NR_MSR;
+ msr = MSR_MFGPT_NR;
mask = 1 << (timer + 24);
break;
case MFGPT_EVENT_NMI:
- msr = MFGPT_NR_MSR;
+ msr = MSR_MFGPT_NR;
mask = 1 << (timer + shift);
break;
case MFGPT_EVENT_IRQ:
- msr = MFGPT_IRQ_MSR;
+ msr = MSR_MFGPT_IRQ;
mask = 1 << (timer + shift);
break;
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)
+int geode_mfgpt_set_irq(int timer, int cmp, int *irq, int enable)
{
- u32 val, dummy;
- int offset;
+ u32 zsel, lpc, dummy;
+ int shift;
if (timer < 0 || timer >= MFGPT_MAX_TIMERS)
return -EIO;
- if (geode_mfgpt_toggle_event(timer, cmp, MFGPT_EVENT_IRQ, enable))
+ /*
+ * 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;
- rdmsr(MSR_PIC_ZSEL_LOW, val, dummy);
-
- offset = (timer % 4) * 4;
+ /* Choose IRQ: if none supplied, keep IRQ already set or use default */
+ if (!*irq)
+ *irq = (zsel >> shift) & 0xF;
+ if (!*irq)
+ *irq = MFGPT_DEFAULT_IRQ;
- val &= ~((0xF << offset) | (0xF << (offset + 16)));
+ /* 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) {
- val |= (irq & 0x0F) << (offset);
- val |= (irq & 0x0F) << (offset + 16);
+ zsel = (zsel & ~(0xF << shift)) | (*irq << shift);
+ wrmsr(MSR_PIC_ZSEL_LOW, zsel, dummy);
}
- wrmsr(MSR_PIC_ZSEL_LOW, val, dummy);
return 0;
}
{
int i;
- if (!geode_get_dev_base(GEODE_DEV_MFGPT))
- return -ENODEV;
+ if (timers == -1) {
+ /* timers haven't been detected yet */
+ geode_mfgpt_detect();
+ }
+
+ if (!timers)
+ return -1;
+
if (timer >= MFGPT_MAX_TIMERS)
- return -EIO;
+ return -1;
if (timer < 0) {
/* Try to find an available 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 then the PIT. This isn't a general purpose MFGPT driver, but
+ * 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.
*/
static unsigned int mfgpt_tick_mode = CLOCK_EVT_MODE_SHUTDOWN;
static u16 mfgpt_event_clock;
-static int irq = 7;
+static int irq;
static int __init mfgpt_setup(char *str)
{
get_option(&str, &irq);
static void mfgpt_disable_timer(u16 clock)
{
- u16 val = geode_mfgpt_read(clock, MFGPT_REG_SETUP);
- geode_mfgpt_write(clock, MFGPT_REG_SETUP, val & ~MFGPT_SETUP_CNTEN);
+ /* 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 *);
.set_mode = mfgpt_set_mode,
.set_next_event = mfgpt_next_event,
.rating = 250,
- .cpumask = CPU_MASK_ALL,
+ .cpumask = cpu_all_mask,
.shift = 32
};
return 0;
}
-/* Assume (foolishly?), that this interrupt was due to our tick */
-
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);
static struct irqaction mfgptirq = {
.handler = mfgpt_tick,
- .flags = IRQF_DISABLED | IRQF_NOBALANCING,
- .mask = CPU_MASK_NONE,
+ .flags = IRQF_DISABLED | IRQF_NOBALANCING | IRQF_TIMER,
.name = "mfgpt-timer"
};
-static int __init mfgpt_timer_setup(void)
+int __init mfgpt_timer_setup(void)
{
int timer, ret;
u16 val;
mfgpt_event_clock = timer;
/* Set up the IRQ on the MFGPT side */
- if (geode_mfgpt_setup_irq(mfgpt_event_clock, MFGPT_CMP2, irq)) {
+ 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;
}
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, 32);
+ 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 the MFGT timer as a clock event.\n");
+ "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);
+ 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;
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff