diff options
Diffstat (limited to 'arch/arm/plat-orion')
-rw-r--r-- | arch/arm/plat-orion/Makefile | 2 | ||||
-rw-r--r-- | arch/arm/plat-orion/time.c | 203 |
2 files changed, 204 insertions, 1 deletions
diff --git a/arch/arm/plat-orion/Makefile b/arch/arm/plat-orion/Makefile index b33ecb60183d..198f3dde2be3 100644 --- a/arch/arm/plat-orion/Makefile +++ b/arch/arm/plat-orion/Makefile | |||
@@ -2,7 +2,7 @@ | |||
2 | # Makefile for the linux kernel. | 2 | # Makefile for the linux kernel. |
3 | # | 3 | # |
4 | 4 | ||
5 | obj-y := irq.o pcie.o | 5 | obj-y := irq.o pcie.o time.o |
6 | obj-m := | 6 | obj-m := |
7 | obj-n := | 7 | obj-n := |
8 | obj- := | 8 | obj- := |
diff --git a/arch/arm/plat-orion/time.c b/arch/arm/plat-orion/time.c new file mode 100644 index 000000000000..28b5285446e8 --- /dev/null +++ b/arch/arm/plat-orion/time.c | |||
@@ -0,0 +1,203 @@ | |||
1 | /* | ||
2 | * arch/arm/plat-orion/time.c | ||
3 | * | ||
4 | * Marvell Orion SoC timer handling. | ||
5 | * | ||
6 | * This file is licensed under the terms of the GNU General Public | ||
7 | * License version 2. This program is licensed "as is" without any | ||
8 | * warranty of any kind, whether express or implied. | ||
9 | * | ||
10 | * Timer 0 is used as free-running clocksource, while timer 1 is | ||
11 | * used as clock_event_device. | ||
12 | */ | ||
13 | |||
14 | #include <linux/kernel.h> | ||
15 | #include <linux/clockchips.h> | ||
16 | #include <linux/interrupt.h> | ||
17 | #include <linux/irq.h> | ||
18 | #include <asm/mach/time.h> | ||
19 | #include <asm/arch/hardware.h> | ||
20 | |||
21 | /* | ||
22 | * Number of timer ticks per jiffy. | ||
23 | */ | ||
24 | static u32 ticks_per_jiffy; | ||
25 | |||
26 | |||
27 | /* | ||
28 | * Timer block registers. | ||
29 | */ | ||
30 | #define TIMER_CTRL (TIMER_VIRT_BASE + 0x0000) | ||
31 | #define TIMER0_EN 0x0001 | ||
32 | #define TIMER0_RELOAD_EN 0x0002 | ||
33 | #define TIMER1_EN 0x0004 | ||
34 | #define TIMER1_RELOAD_EN 0x0008 | ||
35 | #define TIMER0_RELOAD (TIMER_VIRT_BASE + 0x0010) | ||
36 | #define TIMER0_VAL (TIMER_VIRT_BASE + 0x0014) | ||
37 | #define TIMER1_RELOAD (TIMER_VIRT_BASE + 0x0018) | ||
38 | #define TIMER1_VAL (TIMER_VIRT_BASE + 0x001c) | ||
39 | |||
40 | |||
41 | /* | ||
42 | * Clocksource handling. | ||
43 | */ | ||
44 | static cycle_t orion_clksrc_read(void) | ||
45 | { | ||
46 | return 0xffffffff - readl(TIMER0_VAL); | ||
47 | } | ||
48 | |||
49 | static struct clocksource orion_clksrc = { | ||
50 | .name = "orion_clocksource", | ||
51 | .shift = 20, | ||
52 | .rating = 300, | ||
53 | .read = orion_clksrc_read, | ||
54 | .mask = CLOCKSOURCE_MASK(32), | ||
55 | .flags = CLOCK_SOURCE_IS_CONTINUOUS, | ||
56 | }; | ||
57 | |||
58 | |||
59 | |||
60 | /* | ||
61 | * Clockevent handling. | ||
62 | */ | ||
63 | static int | ||
64 | orion_clkevt_next_event(unsigned long delta, struct clock_event_device *dev) | ||
65 | { | ||
66 | unsigned long flags; | ||
67 | u32 u; | ||
68 | |||
69 | if (delta == 0) | ||
70 | return -ETIME; | ||
71 | |||
72 | local_irq_save(flags); | ||
73 | |||
74 | /* | ||
75 | * Clear and enable clockevent timer interrupt. | ||
76 | */ | ||
77 | writel(~BRIDGE_INT_TIMER1, BRIDGE_CAUSE); | ||
78 | |||
79 | u = readl(BRIDGE_MASK); | ||
80 | u |= BRIDGE_INT_TIMER1; | ||
81 | writel(u, BRIDGE_MASK); | ||
82 | |||
83 | /* | ||
84 | * Setup new clockevent timer value. | ||
85 | */ | ||
86 | writel(delta, TIMER1_VAL); | ||
87 | |||
88 | /* | ||
89 | * Enable the timer. | ||
90 | */ | ||
91 | u = readl(TIMER_CTRL); | ||
92 | u = (u & ~TIMER1_RELOAD_EN) | TIMER1_EN; | ||
93 | writel(u, TIMER_CTRL); | ||
94 | |||
95 | local_irq_restore(flags); | ||
96 | |||
97 | return 0; | ||
98 | } | ||
99 | |||
100 | static void | ||
101 | orion_clkevt_mode(enum clock_event_mode mode, struct clock_event_device *dev) | ||
102 | { | ||
103 | unsigned long flags; | ||
104 | u32 u; | ||
105 | |||
106 | local_irq_save(flags); | ||
107 | if (mode == CLOCK_EVT_MODE_PERIODIC) { | ||
108 | /* | ||
109 | * Setup timer to fire at 1/HZ intervals. | ||
110 | */ | ||
111 | writel(ticks_per_jiffy - 1, TIMER1_RELOAD); | ||
112 | writel(ticks_per_jiffy - 1, TIMER1_VAL); | ||
113 | |||
114 | /* | ||
115 | * Enable timer interrupt. | ||
116 | */ | ||
117 | u = readl(BRIDGE_MASK); | ||
118 | writel(u | BRIDGE_INT_TIMER1, BRIDGE_MASK); | ||
119 | |||
120 | /* | ||
121 | * Enable timer. | ||
122 | */ | ||
123 | u = readl(TIMER_CTRL); | ||
124 | writel(u | TIMER1_EN | TIMER1_RELOAD_EN, TIMER_CTRL); | ||
125 | } else { | ||
126 | /* | ||
127 | * Disable timer. | ||
128 | */ | ||
129 | u = readl(TIMER_CTRL); | ||
130 | writel(u & ~TIMER1_EN, TIMER_CTRL); | ||
131 | |||
132 | /* | ||
133 | * Disable timer interrupt. | ||
134 | */ | ||
135 | u = readl(BRIDGE_MASK); | ||
136 | writel(u & ~BRIDGE_INT_TIMER1, BRIDGE_MASK); | ||
137 | |||
138 | /* | ||
139 | * ACK pending timer interrupt. | ||
140 | */ | ||
141 | writel(~BRIDGE_INT_TIMER1, BRIDGE_CAUSE); | ||
142 | |||
143 | } | ||
144 | local_irq_restore(flags); | ||
145 | } | ||
146 | |||
147 | static struct clock_event_device orion_clkevt = { | ||
148 | .name = "orion_tick", | ||
149 | .features = CLOCK_EVT_FEAT_ONESHOT | CLOCK_EVT_FEAT_PERIODIC, | ||
150 | .shift = 32, | ||
151 | .rating = 300, | ||
152 | .cpumask = CPU_MASK_CPU0, | ||
153 | .set_next_event = orion_clkevt_next_event, | ||
154 | .set_mode = orion_clkevt_mode, | ||
155 | }; | ||
156 | |||
157 | static irqreturn_t orion_timer_interrupt(int irq, void *dev_id) | ||
158 | { | ||
159 | /* | ||
160 | * ACK timer interrupt and call event handler. | ||
161 | */ | ||
162 | writel(~BRIDGE_INT_TIMER1, BRIDGE_CAUSE); | ||
163 | orion_clkevt.event_handler(&orion_clkevt); | ||
164 | |||
165 | return IRQ_HANDLED; | ||
166 | } | ||
167 | |||
168 | static struct irqaction orion_timer_irq = { | ||
169 | .name = "orion_tick", | ||
170 | .flags = IRQF_DISABLED | IRQF_TIMER, | ||
171 | .handler = orion_timer_interrupt | ||
172 | }; | ||
173 | |||
174 | void __init orion_time_init(unsigned int irq, unsigned int tclk) | ||
175 | { | ||
176 | u32 u; | ||
177 | |||
178 | ticks_per_jiffy = (tclk + HZ/2) / HZ; | ||
179 | |||
180 | |||
181 | /* | ||
182 | * Setup free-running clocksource timer (interrupts | ||
183 | * disabled.) | ||
184 | */ | ||
185 | writel(0xffffffff, TIMER0_VAL); | ||
186 | writel(0xffffffff, TIMER0_RELOAD); | ||
187 | u = readl(BRIDGE_MASK); | ||
188 | writel(u & ~BRIDGE_INT_TIMER0, BRIDGE_MASK); | ||
189 | u = readl(TIMER_CTRL); | ||
190 | writel(u | TIMER0_EN | TIMER0_RELOAD_EN, TIMER_CTRL); | ||
191 | orion_clksrc.mult = clocksource_hz2mult(tclk, orion_clksrc.shift); | ||
192 | clocksource_register(&orion_clksrc); | ||
193 | |||
194 | |||
195 | /* | ||
196 | * Setup clockevent timer (interrupt-driven.) | ||
197 | */ | ||
198 | setup_irq(irq, &orion_timer_irq); | ||
199 | orion_clkevt.mult = div_sc(tclk, NSEC_PER_SEC, orion_clkevt.shift); | ||
200 | orion_clkevt.max_delta_ns = clockevent_delta2ns(0xfffffffe, &orion_clkevt); | ||
201 | orion_clkevt.min_delta_ns = clockevent_delta2ns(1, &orion_clkevt); | ||
202 | clockevents_register_device(&orion_clkevt); | ||
203 | } | ||