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-rw-r--r--examples/standalone/timer.c349
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diff --git a/examples/standalone/timer.c b/examples/standalone/timer.c
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+++ b/examples/standalone/timer.c
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+/*
+ * (C) Copyright 2000
+ * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * 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.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+
+#include <common.h>
+#include <commproc.h>
+#include <mpc8xx_irq.h>
+#include <exports.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+#undef DEBUG
+
+#define TIMER_PERIOD 1000000 /* 1 second clock */
+
+static void timer_handler (void *arg);
+
+
+/* Access functions for the Machine State Register */
+static __inline__ unsigned long get_msr(void)
+{
+ unsigned long msr;
+
+ asm volatile("mfmsr %0" : "=r" (msr) :);
+ return msr;
+}
+
+static __inline__ void set_msr(unsigned long msr)
+{
+ asm volatile("mtmsr %0" : : "r" (msr));
+}
+
+/*
+ * Definitions to access the CPM Timer registers
+ * See 8xx_immap.h for Internal Memory Map layout,
+ * and commproc.h for CPM Interrupt vectors (aka "IRQ"s)
+ */
+
+typedef struct tid_8xx_cpmtimer_s {
+ int cpm_vec; /* CPM Interrupt Vector for this timer */
+ ushort *tgcrp; /* Pointer to Timer Global Config Reg. */
+ ushort *tmrp; /* Pointer to Timer Mode Register */
+ ushort *trrp; /* Pointer to Timer Reference Register */
+ ushort *tcrp; /* Pointer to Timer Capture Register */
+ ushort *tcnp; /* Pointer to Timer Counter Register */
+ ushort *terp; /* Pointer to Timer Event Register */
+} tid_8xx_cpmtimer_t;
+
+#ifndef CLOCKRATE
+# define CLOCKRATE 64
+#endif
+
+#define CPMT_CLOCK_DIV 16
+#define CPMT_MAX_PRESCALER 256
+#define CPMT_MAX_REFERENCE 65535 /* max. unsigned short */
+
+#define CPMT_MAX_TICKS (CPMT_MAX_REFERENCE * CPMT_MAX_PRESCALER)
+#define CPMT_MAX_TICKS_WITH_DIV (CPMT_MAX_REFERENCE * CPMT_MAX_PRESCALER * CPMT_CLOCK_DIV)
+#define CPMT_MAX_INTERVAL (CPMT_MAX_TICKS_WITH_DIV / CLOCKRATE)
+
+/* For now: always use max. prescaler value */
+#define CPMT_PRESCALER (CPMT_MAX_PRESCALER)
+
+/* CPM Timer Event Register Bits */
+#define CPMT_EVENT_CAP 0x0001 /* Capture Event */
+#define CPMT_EVENT_REF 0x0002 /* Reference Counter Event */
+
+/* CPM Timer Global Config Register */
+#define CPMT_GCR_RST 0x0001 /* Reset Timer */
+#define CPMT_GCR_STP 0x0002 /* Stop Timer */
+#define CPMT_GCR_FRZ 0x0004 /* Freeze Timer */
+#define CPMT_GCR_GM_CAS 0x0008 /* Gate Mode / Cascade Timers */
+#define CPMT_GCR_MASK (CPMT_GCR_RST|CPMT_GCR_STP|CPMT_GCR_FRZ|CPMT_GCR_GM_CAS)
+
+/* CPM Timer Mode register */
+#define CPMT_MR_GE 0x0001 /* Gate Enable */
+#define CPMT_MR_ICLK_CASC 0x0000 /* Clock internally cascaded */
+#define CPMT_MR_ICLK_CLK 0x0002 /* Clock = system clock */
+#define CPMT_MR_ICLK_CLKDIV 0x0004 /* Clock = system clock / 16 */
+#define CPMT_MR_ICLK_TIN 0x0006 /* Clock = TINx signal */
+#define CPMT_MR_FRR 0x0008 /* Free Run / Restart */
+#define CPMT_MR_ORI 0x0010 /* Out. Reference Interrupt En. */
+#define CPMT_MR_OM 0x0020 /* Output Mode */
+#define CPMT_MR_CE_DIS 0x0000 /* Capture/Interrupt disabled */
+#define CPMT_MR_CE_RISE 0x0040 /* Capt./Interr. on rising TIN */
+#define CPMT_MR_CE_FALL 0x0080 /* Capt./Interr. on falling TIN */
+#define CPMT_MR_CE_ANY 0x00C0 /* Capt./Interr. on any TIN edge*/
+
+
+/*
+ * which CPM timer to use - index starts at 0 (= timer 1)
+ */
+#define TID_TIMER_ID 0 /* use CPM timer 1 */
+
+void setPeriod (tid_8xx_cpmtimer_t *hwp, ulong interval);
+
+static char *usage = "\n[q, b, e, ?] ";
+
+int timer (int argc, char *argv[])
+{
+ cpmtimer8xx_t *cpmtimerp; /* Pointer to the CPM Timer structure */
+ tid_8xx_cpmtimer_t hw;
+ tid_8xx_cpmtimer_t *hwp = &hw;
+ int c;
+ int running;
+
+ app_startup(argv);
+
+ /* Pointer to CPM Timer structure */
+ cpmtimerp = &((immap_t *) gd->bd->bi_immr_base)->im_cpmtimer;
+
+ printf ("TIMERS=0x%x\n", (unsigned) cpmtimerp);
+
+ /* Initialize pointers depending on which timer we use */
+ switch (TID_TIMER_ID) {
+ case 0:
+ hwp->tmrp = &(cpmtimerp->cpmt_tmr1);
+ hwp->trrp = &(cpmtimerp->cpmt_trr1);
+ hwp->tcrp = &(cpmtimerp->cpmt_tcr1);
+ hwp->tcnp = &(cpmtimerp->cpmt_tcn1);
+ hwp->terp = &(cpmtimerp->cpmt_ter1);
+ hwp->cpm_vec = CPMVEC_TIMER1;
+ break;
+ case 1:
+ hwp->tmrp = &(cpmtimerp->cpmt_tmr2);
+ hwp->trrp = &(cpmtimerp->cpmt_trr2);
+ hwp->tcrp = &(cpmtimerp->cpmt_tcr2);
+ hwp->tcnp = &(cpmtimerp->cpmt_tcn2);
+ hwp->terp = &(cpmtimerp->cpmt_ter2);
+ hwp->cpm_vec = CPMVEC_TIMER2;
+ break;
+ case 2:
+ hwp->tmrp = &(cpmtimerp->cpmt_tmr3);
+ hwp->trrp = &(cpmtimerp->cpmt_trr3);
+ hwp->tcrp = &(cpmtimerp->cpmt_tcr3);
+ hwp->tcnp = &(cpmtimerp->cpmt_tcn3);
+ hwp->terp = &(cpmtimerp->cpmt_ter3);
+ hwp->cpm_vec = CPMVEC_TIMER3;
+ break;
+ case 3:
+ hwp->tmrp = &(cpmtimerp->cpmt_tmr4);
+ hwp->trrp = &(cpmtimerp->cpmt_trr4);
+ hwp->tcrp = &(cpmtimerp->cpmt_tcr4);
+ hwp->tcnp = &(cpmtimerp->cpmt_tcn4);
+ hwp->terp = &(cpmtimerp->cpmt_ter4);
+ hwp->cpm_vec = CPMVEC_TIMER4;
+ break;
+ }
+
+ hwp->tgcrp = &cpmtimerp->cpmt_tgcr;
+
+ printf ("Using timer %d\n"
+ "tgcr @ 0x%x, tmr @ 0x%x, trr @ 0x%x,"
+ " tcr @ 0x%x, tcn @ 0x%x, ter @ 0x%x\n",
+ TID_TIMER_ID + 1,
+ (unsigned) hwp->tgcrp,
+ (unsigned) hwp->tmrp,
+ (unsigned) hwp->trrp,
+ (unsigned) hwp->tcrp,
+ (unsigned) hwp->tcnp,
+ (unsigned) hwp->terp
+ );
+
+ /* reset timer */
+ *hwp->tgcrp &= ~(CPMT_GCR_MASK << TID_TIMER_ID);
+
+ /* clear all events */
+ *hwp->terp = (CPMT_EVENT_CAP | CPMT_EVENT_REF);
+
+ printf (usage);
+ running = 0;
+ while ((c = getc()) != 'q') {
+ if (c == 'b') {
+
+ setPeriod (hwp, TIMER_PERIOD); /* Set period and start ticking */
+
+ /* Install interrupt handler (enable timer in CIMR) */
+ install_hdlr (hwp->cpm_vec, timer_handler, hwp);
+
+ printf ("Enabling timer\n");
+
+ /* enable timer */
+ *hwp->tgcrp |= (CPMT_GCR_RST << TID_TIMER_ID);
+ running = 1;
+
+#ifdef DEBUG
+ printf ("tgcr=0x%x, tmr=0x%x, trr=0x%x,"
+ " tcr=0x%x, tcn=0x%x, ter=0x%x\n",
+ *hwp->tgcrp, *hwp->tmrp, *hwp->trrp,
+ *hwp->tcrp, *hwp->tcnp, *hwp->terp
+ );
+#endif
+ } else if (c == 'e') {
+
+ printf ("Stopping timer\n");
+
+ *hwp->tgcrp &= ~(CPMT_GCR_MASK << TID_TIMER_ID);
+ running = 0;
+
+#ifdef DEBUG
+ printf ("tgcr=0x%x, tmr=0x%x, trr=0x%x,"
+ " tcr=0x%x, tcn=0x%x, ter=0x%x\n",
+ *hwp->tgcrp, *hwp->tmrp, *hwp->trrp,
+ *hwp->tcrp, *hwp->tcnp, *hwp->terp
+ );
+#endif
+ /* Uninstall interrupt handler */
+ free_hdlr (hwp->cpm_vec);
+
+ } else if (c == '?') {
+#ifdef DEBUG
+ cpic8xx_t *cpm_icp = &((immap_t *) gd->bd->bi_immr_base)->im_cpic;
+ sysconf8xx_t *siup = &((immap_t *) gd->bd->bi_immr_base)->im_siu_conf;
+#endif
+
+ printf ("\ntgcr=0x%x, tmr=0x%x, trr=0x%x,"
+ " tcr=0x%x, tcn=0x%x, ter=0x%x\n",
+ *hwp->tgcrp, *hwp->tmrp, *hwp->trrp,
+ *hwp->tcrp, *hwp->tcnp, *hwp->terp
+ );
+#ifdef DEBUG
+ printf ("SIUMCR=0x%08lx, SYPCR=0x%08lx,"
+ " SIMASK=0x%08lx, SIPEND=0x%08lx\n",
+ siup->sc_siumcr,
+ siup->sc_sypcr,
+ siup->sc_simask,
+ siup->sc_sipend
+ );
+
+ printf ("CIMR=0x%08lx, CICR=0x%08lx, CIPR=0x%08lx\n",
+ cpm_icp->cpic_cimr,
+ cpm_icp->cpic_cicr,
+ cpm_icp->cpic_cipr
+ );
+#endif
+ } else {
+ printf ("\nEnter: q - quit, b - start timer, e - stop timer, ? - get status\n");
+ }
+ printf (usage);
+ }
+ if (running) {
+ printf ("Stopping timer\n");
+ *hwp->tgcrp &= ~(CPMT_GCR_MASK << TID_TIMER_ID);
+ free_hdlr (hwp->cpm_vec);
+ }
+
+ return (0);
+}
+
+
+/* Set period in microseconds and start.
+ * Truncate to maximum period if more than this is requested - but warn about it.
+ */
+
+void setPeriod (tid_8xx_cpmtimer_t *hwp, ulong interval)
+{
+ unsigned short prescaler;
+ unsigned long ticks;
+
+ printf ("Set interval %ld us\n", interval);
+
+ /* Warn if requesting longer period than possible */
+ if (interval > CPMT_MAX_INTERVAL) {
+ printf ("Truncate interval %ld to maximum (%d)\n",
+ interval, CPMT_MAX_INTERVAL);
+ interval = CPMT_MAX_INTERVAL;
+ }
+ /*
+ * Check if we want to use clock divider:
+ * Since the reference counter can be incremented only in integer steps,
+ * we try to keep it as big as possible to allow the resulting period to be
+ * as precise as possible.
+ */
+ /* prescaler, enable interrupt, restart after ref count is reached */
+ prescaler = (ushort) ((CPMT_PRESCALER - 1) << 8) |
+ CPMT_MR_ORI |
+ CPMT_MR_FRR;
+
+ ticks = ((ulong) CLOCKRATE * interval);
+
+ if (ticks > CPMT_MAX_TICKS) {
+ ticks /= CPMT_CLOCK_DIV;
+ prescaler |= CPMT_MR_ICLK_CLKDIV; /* use system clock divided by 16 */
+ } else {
+ prescaler |= CPMT_MR_ICLK_CLK; /* use system clock without divider */
+ }
+
+#ifdef DEBUG
+ printf ("clock/%d, prescale factor %d, reference %ld, ticks %ld\n",
+ (ticks > CPMT_MAX_TICKS) ? CPMT_CLOCK_DIV : 1,
+ CPMT_PRESCALER,
+ (ticks / CPMT_PRESCALER),
+ ticks
+ );
+#endif
+
+ /* set prescaler register */
+ *hwp->tmrp = prescaler;
+
+ /* clear timer counter */
+ *hwp->tcnp = 0;
+
+ /* set reference register */
+ *hwp->trrp = (unsigned short) (ticks / CPMT_PRESCALER);
+
+#ifdef DEBUG
+ printf ("tgcr=0x%x, tmr=0x%x, trr=0x%x,"
+ " tcr=0x%x, tcn=0x%x, ter=0x%x\n",
+ *hwp->tgcrp, *hwp->tmrp, *hwp->trrp,
+ *hwp->tcrp, *hwp->tcnp, *hwp->terp
+ );
+#endif
+}
+
+/*
+ * Handler for CPMVEC_TIMER1 interrupt
+ */
+static
+void timer_handler (void *arg)
+{
+ tid_8xx_cpmtimer_t *hwp = (tid_8xx_cpmtimer_t *)arg;
+
+ /* printf ("** TER1=%04x ** ", *hwp->terp); */
+
+ /* just for demonstration */
+ printf (".");
+
+ /* clear all possible events: Ref. and Cap. */
+ *hwp->terp = (CPMT_EVENT_CAP | CPMT_EVENT_REF);
+}
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