xref: /openbmc/u-boot/arch/arm/mach-orion5x/timer.c (revision 274bced8)
1 /*
2   * Copyright (C) 2010 Albert ARIBAUD <albert.u.boot@aribaud.net>
3  *
4  * Based on original Kirkwood support which is
5  * Copyright (C) Marvell International Ltd. and its affiliates
6  * Written-by: Prafulla Wadaskar <prafulla@marvell.com>
7  *
8  * SPDX-License-Identifier:	GPL-2.0+
9  */
10 
11 #include <common.h>
12 #include <asm/io.h>
13 
14 #define UBOOT_CNTR	0	/* counter to use for uboot timer */
15 
16 /* Timer reload and current value registers */
17 struct orion5x_tmr_val {
18 	u32 reload;	/* Timer reload reg */
19 	u32 val;	/* Timer value reg */
20 };
21 
22 /* Timer registers */
23 struct orion5x_tmr_registers {
24 	u32 ctrl;	/* Timer control reg */
25 	u32 pad[3];
26 	struct orion5x_tmr_val tmr[2];
27 	u32 wdt_reload;
28 	u32 wdt_val;
29 };
30 
31 struct orion5x_tmr_registers *orion5x_tmr_regs =
32 	(struct orion5x_tmr_registers *)ORION5X_TIMER_BASE;
33 
34 /*
35  * ARM Timers Registers Map
36  */
37 #define CNTMR_CTRL_REG			(&orion5x_tmr_regs->ctrl)
38 #define CNTMR_RELOAD_REG(tmrnum)	(&orion5x_tmr_regs->tmr[tmrnum].reload)
39 #define CNTMR_VAL_REG(tmrnum)		(&orion5x_tmr_regs->tmr[tmrnum].val)
40 
41 /*
42  * ARM Timers Control Register
43  * CPU_TIMERS_CTRL_REG (CTCR)
44  */
45 #define CTCR_ARM_TIMER_EN_OFFS(cntr)	(cntr * 2)
46 #define CTCR_ARM_TIMER_EN_MASK(cntr)	(1 << CTCR_ARM_TIMER_EN_OFFS)
47 #define CTCR_ARM_TIMER_EN(cntr)		(1 << CTCR_ARM_TIMER_EN_OFFS(cntr))
48 #define CTCR_ARM_TIMER_DIS(cntr)	(0 << CTCR_ARM_TIMER_EN_OFFS(cntr))
49 
50 #define CTCR_ARM_TIMER_AUTO_OFFS(cntr)	((cntr * 2) + 1)
51 #define CTCR_ARM_TIMER_AUTO_MASK(cntr)	(1 << 1)
52 #define CTCR_ARM_TIMER_AUTO_EN(cntr)	(1 << CTCR_ARM_TIMER_AUTO_OFFS(cntr))
53 #define CTCR_ARM_TIMER_AUTO_DIS(cntr)	(0 << CTCR_ARM_TIMER_AUTO_OFFS(cntr))
54 
55 /*
56  * ARM Timer\Watchdog Reload Register
57  * CNTMR_RELOAD_REG (TRR)
58  */
59 #define TRG_ARM_TIMER_REL_OFFS		0
60 #define TRG_ARM_TIMER_REL_MASK		0xffffffff
61 
62 /*
63  * ARM Timer\Watchdog Register
64  * CNTMR_VAL_REG (TVRG)
65  */
66 #define TVR_ARM_TIMER_OFFS		0
67 #define TVR_ARM_TIMER_MASK		0xffffffff
68 #define TVR_ARM_TIMER_MAX		0xffffffff
69 #define TIMER_LOAD_VAL 			0xffffffff
70 
71 static inline ulong read_timer(void)
72 {
73 	return readl(CNTMR_VAL_REG(UBOOT_CNTR))
74 	      / (CONFIG_SYS_TCLK / 1000);
75 }
76 
77 DECLARE_GLOBAL_DATA_PTR;
78 
79 #define timestamp gd->arch.tbl
80 #define lastdec gd->arch.lastinc
81 
82 ulong get_timer_masked(void)
83 {
84 	ulong now = read_timer();
85 
86 	if (lastdec >= now) {
87 		/* normal mode */
88 		timestamp += lastdec - now;
89 	} else {
90 		/* we have an overflow ... */
91 		timestamp += lastdec +
92 			(TIMER_LOAD_VAL / (CONFIG_SYS_TCLK / 1000)) - now;
93 	}
94 	lastdec = now;
95 
96 	return timestamp;
97 }
98 
99 ulong get_timer(ulong base)
100 {
101 	return get_timer_masked() - base;
102 }
103 
104 static inline ulong uboot_cntr_val(void)
105 {
106 	return readl(CNTMR_VAL_REG(UBOOT_CNTR));
107 }
108 
109 void __udelay(unsigned long usec)
110 {
111 	uint current;
112 	ulong delayticks;
113 
114 	current = uboot_cntr_val();
115 	delayticks = (usec * (CONFIG_SYS_TCLK / 1000000));
116 
117 	if (current < delayticks) {
118 		delayticks -= current;
119 		while (uboot_cntr_val() < current)
120 			;
121 		while ((TIMER_LOAD_VAL - delayticks) < uboot_cntr_val())
122 			;
123 	} else {
124 		while (uboot_cntr_val() > (current - delayticks))
125 			;
126 	}
127 }
128 
129 /*
130  * init the counter
131  */
132 int timer_init(void)
133 {
134 	unsigned int cntmrctrl;
135 
136 	/* load value into timer */
137 	writel(TIMER_LOAD_VAL, CNTMR_RELOAD_REG(UBOOT_CNTR));
138 	writel(TIMER_LOAD_VAL, CNTMR_VAL_REG(UBOOT_CNTR));
139 
140 	/* enable timer in auto reload mode */
141 	cntmrctrl = readl(CNTMR_CTRL_REG);
142 	cntmrctrl |= CTCR_ARM_TIMER_EN(UBOOT_CNTR);
143 	cntmrctrl |= CTCR_ARM_TIMER_AUTO_EN(UBOOT_CNTR);
144 	writel(cntmrctrl, CNTMR_CTRL_REG);
145 	return 0;
146 }
147 
148 void timer_init_r(void)
149 {
150 	/* init the timestamp and lastdec value */
151 	lastdec = read_timer();
152 	timestamp = 0;
153 }
154 
155 /*
156  * This function is derived from PowerPC code (read timebase as long long).
157  * On ARM it just returns the timer value.
158  */
159 unsigned long long get_ticks(void)
160 {
161 	return get_timer(0);
162 }
163 
164 /*
165  * This function is derived from PowerPC code (timebase clock frequency).
166  * On ARM it returns the number of timer ticks per second.
167  */
168 ulong get_tbclk (void)
169 {
170 	return (ulong)CONFIG_SYS_HZ;
171 }
172