1 /* 2 * (C) Copyright 2002 3 * Sysgo Real-Time Solutions, GmbH <www.elinos.com> 4 * Marius Groeger <mgroeger@sysgo.de> 5 * 6 * (C) Copyright 2002 7 * Sysgo Real-Time Solutions, GmbH <www.elinos.com> 8 * Alex Zuepke <azu@sysgo.de> 9 * 10 * See file CREDITS for list of people who contributed to this 11 * project. 12 * 13 * This program is free software; you can redistribute it and/or 14 * modify it under the terms of the GNU General Public License as 15 * published by the Free Software Foundation; either version 2 of 16 * the License, or (at your option) any later version. 17 * 18 * This program is distributed in the hope that it will be useful, 19 * but WITHOUT ANY WARRANTY; without even the implied warranty of 20 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 21 * GNU General Public License for more details. 22 * 23 * You should have received a copy of the GNU General Public License 24 * along with this program; if not, write to the Free Software 25 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, 26 * MA 02111-1307 USA 27 */ 28 29 #include <asm/arch/pxa-regs.h> 30 #include <asm/io.h> 31 #include <common.h> 32 #include <div64.h> 33 34 #ifdef CONFIG_USE_IRQ 35 #error: interrupts not implemented yet 36 #endif 37 38 #if defined(CONFIG_PXA27X) || defined(CONFIG_CPU_MONAHANS) 39 #define TIMER_FREQ_HZ 3250000 40 #elif defined(CONFIG_PXA250) 41 #define TIMER_FREQ_HZ 3686400 42 #else 43 #error "Timer frequency unknown - please config PXA CPU type" 44 #endif 45 46 static inline unsigned long long tick_to_time(unsigned long long tick) 47 { 48 tick *= CONFIG_SYS_HZ; 49 do_div(tick, TIMER_FREQ_HZ); 50 return tick; 51 } 52 53 static inline unsigned long long us_to_tick(unsigned long long us) 54 { 55 us = us * TIMER_FREQ_HZ + 999999; 56 do_div(us, 1000000); 57 return us; 58 } 59 60 int timer_init (void) 61 { 62 writel(0, OSCR); 63 64 return 0; 65 } 66 67 ulong get_timer (ulong base) 68 { 69 return get_timer_masked () - base; 70 } 71 72 void __udelay (unsigned long usec) 73 { 74 udelay_masked (usec); 75 } 76 77 ulong get_timer_masked (void) 78 { 79 return tick_to_time(get_ticks()); 80 } 81 82 void udelay_masked (unsigned long usec) 83 { 84 unsigned long long tmp; 85 ulong tmo; 86 87 tmo = us_to_tick(usec); 88 tmp = get_ticks() + tmo; /* get current timestamp */ 89 90 while (get_ticks() < tmp) /* loop till event */ 91 /*NOP*/; 92 93 } 94 95 /* 96 * This function is derived from PowerPC code (read timebase as long long). 97 * On ARM it just returns the timer value. 98 */ 99 unsigned long long get_ticks(void) 100 { 101 return readl(OSCR); 102 } 103 104 /* 105 * This function is derived from PowerPC code (timebase clock frequency). 106 * On ARM it returns the number of timer ticks per second. 107 */ 108 ulong get_tbclk (void) 109 { 110 ulong tbclk; 111 tbclk = TIMER_FREQ_HZ; 112 return tbclk; 113 } 114