1 /* 2 * (C) Copyright 2009 3 * Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com> 4 * 5 * (C) Copyright 2007-2008 6 * Nobobuhiro Iwamatsu <iwamatsu@nigauri.org> 7 * 8 * (C) Copyright 2003 9 * Wolfgang Denk, DENX Software Engineering, wd@denx.de. 10 * 11 * See file CREDITS for list of people who contributed to this 12 * project. 13 * 14 * This program is free software; you can redistribute it and/or 15 * modify it under the terms of the GNU General Public License as 16 * published by the Free Software Foundation; either version 2 of 17 * the License, or (at your option) any later version. 18 * 19 * This program is distributed in the hope that it will be useful, 20 * but WITHOUT ANY WARRANTY; without even the implied warranty of 21 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 22 * GNU General Public License for more details. 23 * 24 * You should have received a copy of the GNU General Public License 25 * along with this program; if not, write to the Free Software 26 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, 27 * MA 02111-1307 USA 28 */ 29 30 #include <common.h> 31 #include <div64.h> 32 #include <asm/processor.h> 33 #include <asm/clk.h> 34 #include <asm/io.h> 35 36 #define TMU_MAX_COUNTER (~0UL) 37 38 static ulong timer_freq; 39 40 static inline unsigned long long tick_to_time(unsigned long long tick) 41 { 42 tick *= CONFIG_SYS_HZ; 43 do_div(tick, timer_freq); 44 45 return tick; 46 } 47 48 static inline unsigned long long usec_to_tick(unsigned long long usec) 49 { 50 usec *= timer_freq; 51 do_div(usec, 1000000); 52 53 return usec; 54 } 55 56 static void tmu_timer_start (unsigned int timer) 57 { 58 if (timer > 2) 59 return; 60 writeb(readb(TSTR) | (1 << timer), TSTR); 61 } 62 63 static void tmu_timer_stop (unsigned int timer) 64 { 65 if (timer > 2) 66 return; 67 writeb(readb(TSTR) & ~(1 << timer), TSTR); 68 } 69 70 int timer_init (void) 71 { 72 /* Divide clock by CONFIG_SYS_TMU_CLK_DIV */ 73 u16 bit = 0; 74 75 switch (CONFIG_SYS_TMU_CLK_DIV) { 76 case 1024: 77 bit = 4; 78 break; 79 case 256: 80 bit = 3; 81 break; 82 case 64: 83 bit = 2; 84 break; 85 case 16: 86 bit = 1; 87 break; 88 case 4: 89 default: 90 break; 91 } 92 writew(readw(TCR0) | bit, TCR0); 93 94 /* Calc clock rate */ 95 timer_freq = get_tmu0_clk_rate() >> ((bit + 1) * 2); 96 97 tmu_timer_stop(0); 98 tmu_timer_start(0); 99 100 return 0; 101 } 102 103 unsigned long long get_ticks (void) 104 { 105 return 0 - readl(TCNT0); 106 } 107 108 void __udelay (unsigned long usec) 109 { 110 unsigned long long tmp; 111 ulong tmo; 112 113 tmo = usec_to_tick(usec); 114 tmp = get_ticks() + tmo; /* get current timestamp */ 115 116 while (get_ticks() < tmp) /* loop till event */ 117 /*NOP*/; 118 } 119 120 unsigned long get_timer (unsigned long base) 121 { 122 /* return msec */ 123 return tick_to_time(get_ticks()) - base; 124 } 125 126 void set_timer (unsigned long t) 127 { 128 writel((0 - t), TCNT0); 129 } 130 131 void reset_timer (void) 132 { 133 tmu_timer_stop(0); 134 set_timer (0); 135 tmu_timer_start(0); 136 } 137 138 unsigned long get_tbclk (void) 139 { 140 return timer_freq; 141 } 142