/* * (C) Copyright 2007 * Sascha Hauer, Pengutronix * * 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 <asm/arch/mx31-regs.h> #define TIMER_BASE 0x53f90000 /* General purpose timer 1 */ /* General purpose timers registers */ #define GPTCR __REG(TIMER_BASE) /* Control register */ #define GPTPR __REG(TIMER_BASE + 0x4) /* Prescaler register */ #define GPTSR __REG(TIMER_BASE + 0x8) /* Status register */ #define GPTCNT __REG(TIMER_BASE + 0x24) /* Counter register */ /* General purpose timers bitfields */ #define GPTCR_SWR (1 << 15) /* Software reset */ #define GPTCR_FRR (1 << 9) /* Freerun / restart */ #define GPTCR_CLKSOURCE_32 (4 << 6) /* Clock source */ #define GPTCR_TEN 1 /* Timer enable */ /* "time" is measured in 1 / CFG_HZ seconds, "tick" is internal timer period */ #ifdef CONFIG_MX31_TIMER_HIGH_PRECISION /* ~0.4% error - measured with stop-watch on 100s boot-delay */ #define TICK_TO_TIME(t) ((t) * CFG_HZ / CONFIG_MX31_CLK32) #define TIME_TO_TICK(t) ((unsigned long long)(t) * CONFIG_MX31_CLK32 / CFG_HZ) #define US_TO_TICK(t) (((unsigned long long)(t) * CONFIG_MX31_CLK32 + \ 999999) / 1000000) #else /* ~2% error */ #define TICK_PER_TIME ((CONFIG_MX31_CLK32 + CFG_HZ / 2) / CFG_HZ) #define US_PER_TICK (1000000 / CONFIG_MX31_CLK32) #define TICK_TO_TIME(t) ((t) / TICK_PER_TIME) #define TIME_TO_TICK(t) ((unsigned long long)(t) * TICK_PER_TIME) #define US_TO_TICK(t) (((t) + US_PER_TICK - 1) / US_PER_TICK) #endif static ulong timestamp; static ulong lastinc; /* nothing really to do with interrupts, just starts up a counter. */ /* The 32768Hz 32-bit timer overruns in 131072 seconds */ int interrupt_init (void) { int i; /* setup GP Timer 1 */ GPTCR = GPTCR_SWR; for (i = 0; i < 100; i++) GPTCR = 0; /* We have no udelay by now */ GPTPR = 0; /* 32Khz */ /* Freerun Mode, PERCLK1 input */ GPTCR |= GPTCR_CLKSOURCE_32 | GPTCR_TEN; return 0; } void reset_timer_masked (void) { /* reset time */ lastinc = GPTCNT; /* capture current incrementer value time */ timestamp = 0; /* start "advancing" time stamp from 0 */ } void reset_timer(void) { reset_timer_masked(); } unsigned long long get_ticks (void) { ulong now = GPTCNT; /* current tick value */ if (now >= lastinc) /* normal mode (non roll) */ /* move stamp forward with absolut diff ticks */ timestamp += (now - lastinc); else /* we have rollover of incrementer */ timestamp += (0xFFFFFFFF - lastinc) + now; lastinc = now; return timestamp; } ulong get_timer_masked (void) { /* * get_ticks() returns a long long (64 bit), it wraps in * 2^64 / CONFIG_MX31_CLK32 = 2^64 / 2^15 = 2^49 ~ 5 * 10^14 (s) ~ * 5 * 10^9 days... and get_ticks() * CFG_HZ wraps in * 5 * 10^6 days - long enough. */ return TICK_TO_TIME(get_ticks()); } ulong get_timer (ulong base) { return get_timer_masked () - base; } void set_timer (ulong t) { timestamp = TIME_TO_TICK(t); } /* delay x useconds AND perserve advance timstamp value */ void udelay (unsigned long usec) { unsigned long long tmp; ulong tmo; tmo = US_TO_TICK(usec); tmp = get_ticks() + tmo; /* get current timestamp */ while (get_ticks() < tmp) /* loop till event */ /*NOP*/; } void reset_cpu (ulong addr) { __REG16(WDOG_BASE) = 4; }