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