1 /* 2 * Copyright (C) 2007,2008 Nobobuhiro Iwamatsu <iwamatsu@nigauri.org> 3 * Copyright (C) 2008 Renesas Solutions Corp. 4 * 5 * (C) Copyright 2003 6 * Wolfgang Denk, DENX Software Engineering, wd@denx.de. 7 * 8 * SPDX-License-Identifier: GPL-2.0+ 9 */ 10 11 #include <common.h> 12 #include <asm/io.h> 13 #include <asm/processor.h> 14 15 #define CMT_CMCSR_INIT 0x0001 /* PCLK/32 */ 16 #define CMT_CMCSR_CALIB 0x0000 17 #define CMT_MAX_COUNTER (0xFFFFFFFF) 18 #define CMT_TIMER_RESET (0xFFFF) 19 20 static vu_long cmt0_timer; 21 22 static void cmt_timer_start(unsigned int timer) 23 { 24 writew(readw(CMSTR) | 0x01, CMSTR); 25 } 26 27 static void cmt_timer_stop(unsigned int timer) 28 { 29 writew(readw(CMSTR) & ~0x01, CMSTR); 30 } 31 32 int timer_init(void) 33 { 34 cmt0_timer = 0; 35 /* Divide clock by 32 */ 36 readw(CMCSR_0); 37 writew(CMT_CMCSR_INIT, CMCSR_0); 38 39 /* User Device 0 only */ 40 cmt_timer_stop(0); 41 writew(CMT_TIMER_RESET, CMCOR_0); 42 cmt_timer_start(0); 43 44 return 0; 45 } 46 47 unsigned long long get_ticks(void) 48 { 49 return cmt0_timer; 50 } 51 52 static vu_long cmcnt = 0; 53 static unsigned long get_usec (void) 54 { 55 ulong data = readw(CMCNT_0); 56 57 if (data >= cmcnt) 58 cmcnt = data - cmcnt; 59 else 60 cmcnt = (CMT_TIMER_RESET - cmcnt) + data; 61 62 if ((cmt0_timer + cmcnt) > CMT_MAX_COUNTER) 63 cmt0_timer = ((cmt0_timer + cmcnt) - CMT_MAX_COUNTER); 64 else 65 cmt0_timer += cmcnt; 66 67 cmcnt = data; 68 return cmt0_timer; 69 } 70 71 /* return msec */ 72 ulong get_timer(ulong base) 73 { 74 return (get_usec() / 1000) - base; 75 } 76 77 void __udelay(unsigned long usec) 78 { 79 unsigned long end = get_usec() + usec; 80 81 while (get_usec() < end) 82 continue; 83 } 84 85 unsigned long get_tbclk(void) 86 { 87 return CONFIG_SH_CMT_CLK_FREQ; 88 } 89