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Diffstat (limited to 'arch/mips/cpu/xburst/timer.c')
| -rw-r--r-- | arch/mips/cpu/xburst/timer.c | 162 |
1 files changed, 162 insertions, 0 deletions
diff --git a/arch/mips/cpu/xburst/timer.c b/arch/mips/cpu/xburst/timer.c new file mode 100644 index 000000000..de6f5daa3 --- /dev/null +++ b/arch/mips/cpu/xburst/timer.c @@ -0,0 +1,162 @@ +/* + * Copyright (c) 2006 + * Ingenic Semiconductor, <jlwei@ingenic.cn> + * + * 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 <config.h> +#include <common.h> +#include <asm/io.h> + +#include <asm/jz4740.h> + +#define TIMER_CHAN 0 +#define TIMER_FDATA 0xffff /* Timer full data value */ + +DECLARE_GLOBAL_DATA_PTR; + +static struct jz4740_tcu *tcu = (struct jz4740_tcu *)JZ4740_TCU_BASE; + +void reset_timer_masked(void) +{ + /* reset time */ + gd->lastinc = readw(&tcu->tcnt0); + gd->tbl = 0; +} + +ulong get_timer_masked(void) +{ + ulong now = readw(&tcu->tcnt0); + + if (gd->lastinc <= now) + gd->tbl += now - gd->lastinc; /* normal mode */ + else { + /* we have an overflow ... */ + gd->tbl += TIMER_FDATA + now - gd->lastinc; + } + + gd->lastinc = now; + + return gd->tbl; +} + +void udelay_masked(unsigned long usec) +{ + ulong tmo; + ulong endtime; + signed long diff; + + /* normalize */ + if (usec >= 1000) { + tmo = usec / 1000; + tmo *= CONFIG_SYS_HZ; + tmo /= 1000; + } else { + if (usec > 1) { + tmo = usec * CONFIG_SYS_HZ; + tmo /= 1000*1000; + } else + tmo = 1; + } + + endtime = get_timer_masked() + tmo; + + do { + ulong now = get_timer_masked(); + diff = endtime - now; + } while (diff >= 0); +} + +int timer_init(void) +{ + writew(TCU_TCSR_PRESCALE256 | TCU_TCSR_EXT_EN, &tcu->tcsr0); + + writew(0, &tcu->tcnt0); + writew(0, &tcu->tdhr0); + writew(TIMER_FDATA, &tcu->tdfr0); + + /* mask irqs */ + writel((1 << TIMER_CHAN) | (1 << (TIMER_CHAN + 16)), &tcu->tmsr); + writel(1 << TIMER_CHAN, &tcu->tscr); /* enable timer clock */ + writeb(1 << TIMER_CHAN, &tcu->tesr); /* start counting up */ + + gd->lastinc = 0; + gd->tbl = 0; + + return 0; +} + +void reset_timer(void) +{ + reset_timer_masked(); +} + +ulong get_timer(ulong base) +{ + return get_timer_masked() - base; +} + +void set_timer(ulong t) +{ + gd->tbl = t; +} + +void __udelay(unsigned long usec) +{ + ulong tmo, tmp; + + /* normalize */ + if (usec >= 1000) { + tmo = usec / 1000; + tmo *= CONFIG_SYS_HZ; + tmo /= 1000; + } else { + if (usec >= 1) { + tmo = usec * CONFIG_SYS_HZ; + tmo /= 1000 * 1000; + } else + tmo = 1; + } + + /* check for rollover during this delay */ + tmp = get_timer(0); + if ((tmp + tmo) < tmp) + reset_timer_masked(); /* timer would roll over */ + else + tmo += tmp; + + while (get_timer_masked() < tmo) + ; +} + +/* + * This function is derived from PowerPC code (read timebase as long long). + * On MIPS it just returns the timer value. + */ +unsigned long long get_ticks(void) +{ + return get_timer(0); +} + +/* + * This function is derived from PowerPC code (timebase clock frequency). + * On MIPS it returns the number of timer ticks per second. + */ +ulong get_tbclk(void) +{ + return CONFIG_SYS_HZ; +} |