1 /* 2 * (C) Copyright 2009 Faraday Technology 3 * Po-Yu Chuang <ratbert@faraday-tech.com> 4 * 5 * Copyright (C) 2011 Andes Technology Corporation 6 * Shawn Lin, Andes Technology Corporation <nobuhiro@andestech.com> 7 * Macpaul Lin, Andes Technology Corporation <macpaul@andestech.com> 8 * 9 * SPDX-License-Identifier: GPL-2.0+ 10 */ 11 #ifndef CONFIG_TIMER 12 #include <common.h> 13 #include <asm/io.h> 14 #include <faraday/fttmr010.h> 15 16 static ulong timestamp; 17 static ulong lastdec; 18 19 int timer_init(void) 20 { 21 struct fttmr010 *tmr = (struct fttmr010 *)CONFIG_FTTMR010_BASE; 22 unsigned int cr; 23 24 debug("%s()\n", __func__); 25 26 /* disable timers */ 27 writel(0, &tmr->cr); 28 29 #ifdef CONFIG_FTTMR010_EXT_CLK 30 /* use 32768Hz oscillator for RTC, WDT, TIMER */ 31 ftpmu010_32768osc_enable(); 32 #endif 33 34 /* setup timer */ 35 writel(TIMER_LOAD_VAL, &tmr->timer3_load); 36 writel(TIMER_LOAD_VAL, &tmr->timer3_counter); 37 writel(0, &tmr->timer3_match1); 38 writel(0, &tmr->timer3_match2); 39 40 /* we don't want timer to issue interrupts */ 41 writel(FTTMR010_TM3_MATCH1 | 42 FTTMR010_TM3_MATCH2 | 43 FTTMR010_TM3_OVERFLOW, 44 &tmr->interrupt_mask); 45 46 cr = readl(&tmr->cr); 47 #ifdef CONFIG_FTTMR010_EXT_CLK 48 cr |= FTTMR010_TM3_CLOCK; /* use external clock */ 49 #endif 50 cr |= FTTMR010_TM3_ENABLE; 51 writel(cr, &tmr->cr); 52 53 /* init the timestamp and lastdec value */ 54 reset_timer_masked(); 55 56 return 0; 57 } 58 59 /* 60 * timer without interrupts 61 */ 62 63 /* 64 * reset time 65 */ 66 void reset_timer_masked(void) 67 { 68 struct fttmr010 *tmr = (struct fttmr010 *)CONFIG_FTTMR010_BASE; 69 70 /* capure current decrementer value time */ 71 #ifdef CONFIG_FTTMR010_EXT_CLK 72 lastdec = readl(&tmr->timer3_counter) / (TIMER_CLOCK / CONFIG_SYS_HZ); 73 #else 74 lastdec = readl(&tmr->timer3_counter) / 75 (CONFIG_SYS_CLK_FREQ / 2 / CONFIG_SYS_HZ); 76 #endif 77 timestamp = 0; /* start "advancing" time stamp from 0 */ 78 79 debug("%s(): lastdec = %lx\n", __func__, lastdec); 80 } 81 82 void reset_timer(void) 83 { 84 debug("%s()\n", __func__); 85 reset_timer_masked(); 86 } 87 88 /* 89 * return timer ticks 90 */ 91 ulong get_timer_masked(void) 92 { 93 struct fttmr010 *tmr = (struct fttmr010 *)CONFIG_FTTMR010_BASE; 94 95 /* current tick value */ 96 #ifdef CONFIG_FTTMR010_EXT_CLK 97 ulong now = readl(&tmr->timer3_counter) / (TIMER_CLOCK / CONFIG_SYS_HZ); 98 #else 99 ulong now = readl(&tmr->timer3_counter) / 100 (CONFIG_SYS_CLK_FREQ / 2 / CONFIG_SYS_HZ); 101 #endif 102 103 debug("%s(): now = %lx, lastdec = %lx\n", __func__, now, lastdec); 104 105 if (lastdec >= now) { 106 /* 107 * normal mode (non roll) 108 * move stamp fordward with absoulte diff ticks 109 */ 110 timestamp += lastdec - now; 111 } else { 112 /* 113 * we have overflow of the count down timer 114 * 115 * nts = ts + ld + (TLV - now) 116 * ts=old stamp, ld=time that passed before passing through -1 117 * (TLV-now) amount of time after passing though -1 118 * nts = new "advancing time stamp"...it could also roll and 119 * cause problems. 120 */ 121 timestamp += lastdec + TIMER_LOAD_VAL - now; 122 } 123 124 lastdec = now; 125 126 debug("%s() returns %lx\n", __func__, timestamp); 127 128 return timestamp; 129 } 130 131 /* 132 * return difference between timer ticks and base 133 */ 134 ulong get_timer(ulong base) 135 { 136 debug("%s(%lx)\n", __func__, base); 137 return get_timer_masked() - base; 138 } 139 140 void set_timer(ulong t) 141 { 142 debug("%s(%lx)\n", __func__, t); 143 timestamp = t; 144 } 145 146 /* delay x useconds AND preserve advance timestamp value */ 147 void __udelay(unsigned long usec) 148 { 149 struct fttmr010 *tmr = (struct fttmr010 *)CONFIG_FTTMR010_BASE; 150 151 #ifdef CONFIG_FTTMR010_EXT_CLK 152 long tmo = usec * (TIMER_CLOCK / 1000) / 1000; 153 #else 154 long tmo = usec * ((CONFIG_SYS_CLK_FREQ / 2) / 1000) / 1000; 155 #endif 156 unsigned long now, last = readl(&tmr->timer3_counter); 157 158 debug("%s(%lu)\n", __func__, usec); 159 while (tmo > 0) { 160 now = readl(&tmr->timer3_counter); 161 if (now > last) /* count down timer overflow */ 162 tmo -= TIMER_LOAD_VAL + last - now; 163 else 164 tmo -= last - now; 165 last = now; 166 } 167 } 168 169 /* 170 * This function is derived from PowerPC code (read timebase as long long). 171 * On ARM it just returns the timer value. 172 */ 173 unsigned long long get_ticks(void) 174 { 175 debug("%s()\n", __func__); 176 return get_timer(0); 177 } 178 179 /* 180 * This function is derived from PowerPC code (timebase clock frequency). 181 * On ARM it returns the number of timer ticks per second. 182 */ 183 ulong get_tbclk(void) 184 { 185 debug("%s()\n", __func__); 186 #ifdef CONFIG_FTTMR010_EXT_CLK 187 return CONFIG_SYS_HZ; 188 #else 189 return CONFIG_SYS_CLK_FREQ; 190 #endif 191 } 192 #endif /* CONFIG_TIMER */ 193