xref: /openbmc/u-boot/arch/arm/mach-orion5x/timer.c (revision 1a68faac)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3   * Copyright (C) 2010 Albert ARIBAUD <albert.u.boot@aribaud.net>
4  *
5  * Based on original Kirkwood support which is
6  * Copyright (C) Marvell International Ltd. and its affiliates
7  * Written-by: Prafulla Wadaskar <prafulla@marvell.com>
8  */
9 
10 #include <common.h>
11 #include <asm/io.h>
12 
13 #define UBOOT_CNTR	0	/* counter to use for uboot timer */
14 
15 /* Timer reload and current value registers */
16 struct orion5x_tmr_val {
17 	u32 reload;	/* Timer reload reg */
18 	u32 val;	/* Timer value reg */
19 };
20 
21 /* Timer registers */
22 struct orion5x_tmr_registers {
23 	u32 ctrl;	/* Timer control reg */
24 	u32 pad[3];
25 	struct orion5x_tmr_val tmr[2];
26 	u32 wdt_reload;
27 	u32 wdt_val;
28 };
29 
30 struct orion5x_tmr_registers *orion5x_tmr_regs =
31 	(struct orion5x_tmr_registers *)ORION5X_TIMER_BASE;
32 
33 /*
34  * ARM Timers Registers Map
35  */
36 #define CNTMR_CTRL_REG			(&orion5x_tmr_regs->ctrl)
37 #define CNTMR_RELOAD_REG(tmrnum)	(&orion5x_tmr_regs->tmr[tmrnum].reload)
38 #define CNTMR_VAL_REG(tmrnum)		(&orion5x_tmr_regs->tmr[tmrnum].val)
39 
40 /*
41  * ARM Timers Control Register
42  * CPU_TIMERS_CTRL_REG (CTCR)
43  */
44 #define CTCR_ARM_TIMER_EN_OFFS(cntr)	(cntr * 2)
45 #define CTCR_ARM_TIMER_EN_MASK(cntr)	(1 << CTCR_ARM_TIMER_EN_OFFS)
46 #define CTCR_ARM_TIMER_EN(cntr)		(1 << CTCR_ARM_TIMER_EN_OFFS(cntr))
47 #define CTCR_ARM_TIMER_DIS(cntr)	(0 << CTCR_ARM_TIMER_EN_OFFS(cntr))
48 
49 #define CTCR_ARM_TIMER_AUTO_OFFS(cntr)	((cntr * 2) + 1)
50 #define CTCR_ARM_TIMER_AUTO_MASK(cntr)	(1 << 1)
51 #define CTCR_ARM_TIMER_AUTO_EN(cntr)	(1 << CTCR_ARM_TIMER_AUTO_OFFS(cntr))
52 #define CTCR_ARM_TIMER_AUTO_DIS(cntr)	(0 << CTCR_ARM_TIMER_AUTO_OFFS(cntr))
53 
54 /*
55  * ARM Timer\Watchdog Reload Register
56  * CNTMR_RELOAD_REG (TRR)
57  */
58 #define TRG_ARM_TIMER_REL_OFFS		0
59 #define TRG_ARM_TIMER_REL_MASK		0xffffffff
60 
61 /*
62  * ARM Timer\Watchdog Register
63  * CNTMR_VAL_REG (TVRG)
64  */
65 #define TVR_ARM_TIMER_OFFS		0
66 #define TVR_ARM_TIMER_MASK		0xffffffff
67 #define TVR_ARM_TIMER_MAX		0xffffffff
68 #define TIMER_LOAD_VAL 			0xffffffff
69 
70 static inline ulong read_timer(void)
71 {
72 	return readl(CNTMR_VAL_REG(UBOOT_CNTR))
73 	      / (CONFIG_SYS_TCLK / 1000);
74 }
75 
76 DECLARE_GLOBAL_DATA_PTR;
77 
78 #define timestamp gd->arch.tbl
79 #define lastdec gd->arch.lastinc
80 
81 static ulong get_timer_masked(void)
82 {
83 	ulong now = read_timer();
84 
85 	if (lastdec >= now) {
86 		/* normal mode */
87 		timestamp += lastdec - now;
88 	} else {
89 		/* we have an overflow ... */
90 		timestamp += lastdec +
91 			(TIMER_LOAD_VAL / (CONFIG_SYS_TCLK / 1000)) - now;
92 	}
93 	lastdec = now;
94 
95 	return timestamp;
96 }
97 
98 ulong get_timer(ulong base)
99 {
100 	return get_timer_masked() - base;
101 }
102 
103 static inline ulong uboot_cntr_val(void)
104 {
105 	return readl(CNTMR_VAL_REG(UBOOT_CNTR));
106 }
107 
108 void __udelay(unsigned long usec)
109 {
110 	uint current;
111 	ulong delayticks;
112 
113 	current = uboot_cntr_val();
114 	delayticks = (usec * (CONFIG_SYS_TCLK / 1000000));
115 
116 	if (current < delayticks) {
117 		delayticks -= current;
118 		while (uboot_cntr_val() < current)
119 			;
120 		while ((TIMER_LOAD_VAL - delayticks) < uboot_cntr_val())
121 			;
122 	} else {
123 		while (uboot_cntr_val() > (current - delayticks))
124 			;
125 	}
126 }
127 
128 /*
129  * init the counter
130  */
131 int timer_init(void)
132 {
133 	unsigned int cntmrctrl;
134 
135 	/* load value into timer */
136 	writel(TIMER_LOAD_VAL, CNTMR_RELOAD_REG(UBOOT_CNTR));
137 	writel(TIMER_LOAD_VAL, CNTMR_VAL_REG(UBOOT_CNTR));
138 
139 	/* enable timer in auto reload mode */
140 	cntmrctrl = readl(CNTMR_CTRL_REG);
141 	cntmrctrl |= CTCR_ARM_TIMER_EN(UBOOT_CNTR);
142 	cntmrctrl |= CTCR_ARM_TIMER_AUTO_EN(UBOOT_CNTR);
143 	writel(cntmrctrl, CNTMR_CTRL_REG);
144 	return 0;
145 }
146 
147 void timer_init_r(void)
148 {
149 	/* init the timestamp and lastdec value */
150 	lastdec = read_timer();
151 	timestamp = 0;
152 }
153 
154 /*
155  * This function is derived from PowerPC code (read timebase as long long).
156  * On ARM it just returns the timer value.
157  */
158 unsigned long long get_ticks(void)
159 {
160 	return get_timer(0);
161 }
162 
163 /*
164  * This function is derived from PowerPC code (timebase clock frequency).
165  * On ARM it returns the number of timer ticks per second.
166  */
167 ulong get_tbclk (void)
168 {
169 	return (ulong)CONFIG_SYS_HZ;
170 }
171