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-rw-r--r--sys/arm/at91/at91_pit.c219
1 files changed, 105 insertions, 114 deletions
diff --git a/sys/arm/at91/at91_pit.c b/sys/arm/at91/at91_pit.c
index 516b4d4..6a6680f 100644
--- a/sys/arm/at91/at91_pit.c
+++ b/sys/arm/at91/at91_pit.c
@@ -1,5 +1,6 @@
/*-
- * Copyright (c) 2010 Yohanes Nugroho. All rights reserved.
+ * Copyright (c) 2009 Gallon Sylvestre. All rights reserved.
+ * Copyright (c) 2010 Greg Ansley. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
@@ -24,110 +25,117 @@
*/
#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
#include <sys/param.h>
-#include <sys/systm.h>
+#include <sys/bus.h>
#include <sys/kernel.h>
#include <sys/module.h>
-#include <sys/time.h>
-#include <sys/bus.h>
#include <sys/resource.h>
+#include <sys/systm.h>
+#include <sys/rman.h>
+#include <sys/time.h>
#include <sys/timetc.h>
#include <sys/watchdog.h>
#include <machine/bus.h>
#include <machine/cpu.h>
#include <machine/cpufunc.h>
-#include <machine/resource.h>
#include <machine/frame.h>
#include <machine/intr.h>
+#include <machine/resource.h>
#include <arm/at91/at91var.h>
#include <arm/at91/at91_pitreg.h>
-#include <arm/at91/at91_pmcvar.h>
-#include <arm/at91/at91sam9g20reg.h>
-__FBSDID("$FreeBSD$");
+static struct pit_softc {
+ struct resource *mem_res; /* Memory resource */
+ void *intrhand; /* Interrupt handle */
+ device_t sc_dev;
+} *sc;
-static struct at91pit_softc {
- bus_space_tag_t sc_st;
- bus_space_handle_t sc_sh;
- device_t sc_dev;
-} *pit_softc;
+static uint32_t timecount = 0;
-#define RD4(off) \
- bus_space_read_4(pit_softc->sc_st, pit_softc->sc_sh, (off))
-#define WR4(off, val) \
- bus_space_write_4(pit_softc->sc_st, pit_softc->sc_sh, (off), (val))
+static inline uint32_t
+RD4(struct pit_softc *sc, bus_size_t off)
+{
+ return (bus_read_4(sc->mem_res, off));
+}
+
+static inline void
+WR4(struct pit_softc *sc, bus_size_t off, uint32_t val)
+{
+ bus_write_4(sc->mem_res, off, val);
+}
static unsigned at91pit_get_timecount(struct timecounter *tc);
-static int clock_intr(void *arg);
+static int pit_intr(void *arg);
+
+#ifndef PIT_PRESCALE
+#define PIT_PRESCALE (16)
+#endif
static struct timecounter at91pit_timecounter = {
at91pit_get_timecount, /* get_timecount */
NULL, /* no poll_pps */
- 0xffffffffu, /* counter mask */
- 0, /* frequency */
- "AT91SAM9261 timer", /* name */
+ 0xffffffff, /* counter mask */
+ 0 / PIT_PRESCALE, /* frequency */
+ "AT91SAM9 timer", /* name */
1000 /* quality */
};
-
-uint32_t
-at91_pit_base(void);
-
-uint32_t
-at91_pit_size(void);
-
static int
at91pit_probe(device_t dev)
{
- device_set_desc(dev, "PIT");
- return (0);
-}
-
-uint32_t
-at91_pit_base(void)
-{
- return (AT91SAM9G20_PIT_BASE);
-}
-uint32_t
-at91_pit_size(void)
-{
- return (AT91SAM9G20_PIT_SIZE);
+ if (at91_is_sam9()) {
+ device_set_desc(dev, "AT91SAM9 PIT");
+ return (0);
+ }
+ return (ENXIO);
}
-static int pit_rate;
-static int pit_cycle;
-static int pit_counter;
-
static int
at91pit_attach(device_t dev)
{
- struct at91_softc *sc = device_get_softc(device_get_parent(dev));
- struct resource *irq;
- int rid = 0;
void *ih;
+ int rid, err = 0;
+ struct at91_softc *at91_sc;
+ struct resource *irq;
+
+ at91_sc = device_get_softc(device_get_parent(dev));
+ sc = device_get_softc(dev);
+ sc->sc_dev = dev;
- pit_softc = device_get_softc(dev);
- pit_softc->sc_st = sc->sc_st;
- pit_softc->sc_dev = dev;
- if (bus_space_subregion(sc->sc_st, sc->sc_sh, at91_pit_base(),
- at91_pit_size(), &pit_softc->sc_sh) != 0)
- panic("couldn't subregion pit registers");
+ rid = 0;
+ sc->mem_res = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid,
+ RF_ACTIVE);
+ if (sc->mem_res == NULL)
+ panic("couldn't allocate register resources");
+
+ rid = 0;
irq = bus_alloc_resource(dev, SYS_RES_IRQ, &rid, 1, 1, 1,
RF_ACTIVE | RF_SHAREABLE);
- if (!irq)
- panic("Unable to allocate IRQ for the system timer");
- else
- bus_setup_intr(dev, irq, INTR_TYPE_CLK,
- clock_intr, NULL, NULL, &ih);
-
-
- device_printf(dev, "AT91SAM9x pit registered\n");
- return (0);
+ if (!irq) {
+ device_printf(dev, "could not allocate interrupt resources.\n");
+ err = ENOMEM;
+ goto out;
+ }
+
+ /* Activate the interrupt. */
+ err = bus_setup_intr(dev, irq, INTR_TYPE_CLK, pit_intr,
+ NULL, NULL, &ih);
+
+ at91pit_timecounter.tc_frequency = at91_master_clock / PIT_PRESCALE;
+ tc_init(&at91pit_timecounter);
+
+ //Enable the PIT here.
+ WR4(sc, PIT_MR,
+ PIT_PIV(at91_master_clock / PIT_PRESCALE / hz) |
+ PIT_EN | PIT_IEN);
+out:
+ return (err);
}
static device_method_t at91pit_methods[] = {
@@ -139,7 +147,7 @@ static device_method_t at91pit_methods[] = {
static driver_t at91pit_driver = {
"at91_pit",
at91pit_methods,
- sizeof(struct at91pit_softc),
+ sizeof(struct pit_softc),
};
static devclass_t at91pit_devclass;
@@ -147,52 +155,58 @@ static devclass_t at91pit_devclass;
DRIVER_MODULE(at91_pit, atmelarm, at91pit_driver, at91pit_devclass, 0, 0);
static int
-clock_intr(void *arg)
+pit_intr(void *arg)
{
-
struct trapframe *fp = arg;
+ uint32_t icnt;
+
+ if (RD4(sc, PIT_SR) & PIT_PITS_DONE) {
+ icnt = RD4(sc, PIT_PIVR) >> 20;
+
+ /* Just add in the overflows we just read */
+ timecount += PIT_PIV(RD4(sc, PIT_MR)) * icnt;
- if (RD4(PIT_SR) & PIT_PITS_DONE) {
- uint32_t pivr = RD4(PIT_PIVR);
- if (PIT_CNT(pivr)>1) {
- printf("cnt = %d\n", PIT_CNT(pivr));
- }
- pit_counter += pit_cycle;
hardclock(TRAPF_USERMODE(fp), TRAPF_PC(fp));
return (FILTER_HANDLED);
}
return (FILTER_STRAY);
}
-static unsigned
+static unsigned
at91pit_get_timecount(struct timecounter *tc)
{
- return pit_counter;
+ uint32_t piir, icnt;
+
+ piir = RD4(sc, PIT_PIIR); /* Current count | over flows */
+ icnt = piir >> 20; /* Overflows */
+ return (timecount + PIT_PIV(piir) + PIT_PIV(RD4(sc, PIT_MR)) * icnt);
}
-/*todo: review this*/
void
-DELAY(int n)
+DELAY(int us)
{
- u_int32_t start, end, cur;
-
- start = RD4(PIT_PIIR);
- n = (n * 1000) / (at91_master_clock / 12);
- if (n <= 0)
- n = 1;
- end = (start + n);
- cur = start;
- if (start > end) {
- while (cur >= start || cur < end)
- cur = RD4(PIT_PIIR);
- } else {
- while (cur < end)
- cur = RD4(PIT_PIIR);
+ int32_t cnt, last, piv;
+ uint64_t pit_freq;
+ const uint64_t mhz = 1E6;
+
+ last = PIT_PIV(RD4(sc, PIT_PIIR));
+
+ /* Max delay ~= 260s. @ 133Mhz */
+ pit_freq = at91_master_clock / PIT_PRESCALE;
+ cnt = ((pit_freq * us) + (mhz -1)) / mhz;
+ cnt = (cnt <= 0) ? 1 : cnt;
+
+ while (cnt > 0) {
+ piv = PIT_PIV(RD4(sc, PIT_PIIR));
+ cnt -= piv - last ;
+ if (piv < last)
+ cnt -= PIT_PIV(~0u) - last;
+ last = piv;
}
}
/*
- * The 3 next functions must be implement with the futur PLL code.
+ * The 3 next functions must be implement with the future PLL code.
*/
void
cpu_startprofclock(void)
@@ -204,30 +218,7 @@ cpu_stopprofclock(void)
{
}
-#define HZ 100
-
void
cpu_initclocks(void)
{
- struct at91_pmc_clock *master;
-
- master = at91_pmc_clock_ref("mck");
- pit_rate = master->hz / 16;
- pit_cycle = (pit_rate + HZ/2) / HZ;
- at91pit_timecounter.tc_frequency = pit_rate;
- WR4(PIT_MR, 0);
-
- while (PIT_PIV(RD4(PIT_PIVR)) != 0);
-
- WR4(PIT_MR, (pit_cycle - 1) | PIT_IEN | PIT_EN);
- tc_init(&at91pit_timecounter);
-}
-
-void
-cpu_reset(void)
-{
- *(volatile int *)(AT91SAM9G20_BASE + AT91SAM9G20_RSTC_BASE +
- RSTC_CR) = RSTC_PROCRST | RSTC_PERRST | RSTC_KEY;
- while (1)
- continue;
}
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