u-boot/examples/standalone/timer.c
Wolfgang Denk 1a4596601f Add GPL-2.0+ SPDX-License-Identifier to source files
Signed-off-by: Wolfgang Denk <wd@denx.de>
[trini: Fixup common/cmd_io.c]
Signed-off-by: Tom Rini <trini@ti.com>
2013-07-24 09:44:38 -04:00

334 lines
8.9 KiB
C

/*
* (C) Copyright 2000
* Wolfgang Denk, DENX Software Engineering, wd@denx.de.
*
* SPDX-License-Identifier: GPL-2.0+
*/
#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 const char usage[] = "\n[q, b, e, ?] ";
int timer (int argc, char * const 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);
puts(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");
}
puts(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);
}