diff options
author | Ben Dooks <ben-linux@fluff.org> | 2010-01-29 04:02:16 -0500 |
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committer | Ben Dooks <ben-linux@fluff.org> | 2010-02-22 19:03:43 -0500 |
commit | 6c6971dc4e8c23bb61bf309898e1693f9c5c8c24 (patch) | |
tree | a8d6ede6ccf66c8ab0e62c5c78308bf050f72253 /arch/arm/plat-samsung/time.c | |
parent | 2c420fe22f3d526691773288807d010068ce3033 (diff) |
ARM: SAMSUNG: Move the last build from plat-s3c to plat-samsung
Move the init.c and time.c files to plat-samsung from plat-s3c, thus
clearing the last files that are being built in here.
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Diffstat (limited to 'arch/arm/plat-samsung/time.c')
-rw-r--r-- | arch/arm/plat-samsung/time.c | 285 |
1 files changed, 285 insertions, 0 deletions
diff --git a/arch/arm/plat-samsung/time.c b/arch/arm/plat-samsung/time.c new file mode 100644 index 000000000000..2231d80ad817 --- /dev/null +++ b/arch/arm/plat-samsung/time.c | |||
@@ -0,0 +1,285 @@ | |||
1 | /* linux/arch/arm/plat-samsung/time.c | ||
2 | * | ||
3 | * Copyright (C) 2003-2005 Simtec Electronics | ||
4 | * Ben Dooks, <ben@simtec.co.uk> | ||
5 | * | ||
6 | * This program is free software; you can redistribute it and/or modify | ||
7 | * it under the terms of the GNU General Public License as published by | ||
8 | * the Free Software Foundation; either version 2 of the License, or | ||
9 | * (at your option) any later version. | ||
10 | * | ||
11 | * This program is distributed in the hope that it will be useful, | ||
12 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | ||
13 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | ||
14 | * GNU General Public License for more details. | ||
15 | * | ||
16 | * You should have received a copy of the GNU General Public License | ||
17 | * along with this program; if not, write to the Free Software | ||
18 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA | ||
19 | */ | ||
20 | |||
21 | #include <linux/kernel.h> | ||
22 | #include <linux/sched.h> | ||
23 | #include <linux/init.h> | ||
24 | #include <linux/interrupt.h> | ||
25 | #include <linux/irq.h> | ||
26 | #include <linux/err.h> | ||
27 | #include <linux/clk.h> | ||
28 | #include <linux/io.h> | ||
29 | #include <linux/platform_device.h> | ||
30 | |||
31 | #include <asm/system.h> | ||
32 | #include <asm/leds.h> | ||
33 | #include <asm/mach-types.h> | ||
34 | |||
35 | #include <asm/irq.h> | ||
36 | #include <mach/map.h> | ||
37 | #include <plat/regs-timer.h> | ||
38 | #include <mach/regs-irq.h> | ||
39 | #include <asm/mach/time.h> | ||
40 | #include <mach/tick.h> | ||
41 | |||
42 | #include <plat/clock.h> | ||
43 | #include <plat/cpu.h> | ||
44 | |||
45 | static unsigned long timer_startval; | ||
46 | static unsigned long timer_usec_ticks; | ||
47 | |||
48 | #ifndef TICK_MAX | ||
49 | #define TICK_MAX (0xffff) | ||
50 | #endif | ||
51 | |||
52 | #define TIMER_USEC_SHIFT 16 | ||
53 | |||
54 | /* we use the shifted arithmetic to work out the ratio of timer ticks | ||
55 | * to usecs, as often the peripheral clock is not a nice even multiple | ||
56 | * of 1MHz. | ||
57 | * | ||
58 | * shift of 14 and 15 are too low for the 12MHz, 16 seems to be ok | ||
59 | * for the current HZ value of 200 without producing overflows. | ||
60 | * | ||
61 | * Original patch by Dimitry Andric, updated by Ben Dooks | ||
62 | */ | ||
63 | |||
64 | |||
65 | /* timer_mask_usec_ticks | ||
66 | * | ||
67 | * given a clock and divisor, make the value to pass into timer_ticks_to_usec | ||
68 | * to scale the ticks into usecs | ||
69 | */ | ||
70 | |||
71 | static inline unsigned long | ||
72 | timer_mask_usec_ticks(unsigned long scaler, unsigned long pclk) | ||
73 | { | ||
74 | unsigned long den = pclk / 1000; | ||
75 | |||
76 | return ((1000 << TIMER_USEC_SHIFT) * scaler + (den >> 1)) / den; | ||
77 | } | ||
78 | |||
79 | /* timer_ticks_to_usec | ||
80 | * | ||
81 | * convert timer ticks to usec. | ||
82 | */ | ||
83 | |||
84 | static inline unsigned long timer_ticks_to_usec(unsigned long ticks) | ||
85 | { | ||
86 | unsigned long res; | ||
87 | |||
88 | res = ticks * timer_usec_ticks; | ||
89 | res += 1 << (TIMER_USEC_SHIFT - 4); /* round up slightly */ | ||
90 | |||
91 | return res >> TIMER_USEC_SHIFT; | ||
92 | } | ||
93 | |||
94 | /*** | ||
95 | * Returns microsecond since last clock interrupt. Note that interrupts | ||
96 | * will have been disabled by do_gettimeoffset() | ||
97 | * IRQs are disabled before entering here from do_gettimeofday() | ||
98 | */ | ||
99 | |||
100 | static unsigned long s3c2410_gettimeoffset (void) | ||
101 | { | ||
102 | unsigned long tdone; | ||
103 | unsigned long tval; | ||
104 | |||
105 | /* work out how many ticks have gone since last timer interrupt */ | ||
106 | |||
107 | tval = __raw_readl(S3C2410_TCNTO(4)); | ||
108 | tdone = timer_startval - tval; | ||
109 | |||
110 | /* check to see if there is an interrupt pending */ | ||
111 | |||
112 | if (s3c24xx_ostimer_pending()) { | ||
113 | /* re-read the timer, and try and fix up for the missed | ||
114 | * interrupt. Note, the interrupt may go off before the | ||
115 | * timer has re-loaded from wrapping. | ||
116 | */ | ||
117 | |||
118 | tval = __raw_readl(S3C2410_TCNTO(4)); | ||
119 | tdone = timer_startval - tval; | ||
120 | |||
121 | if (tval != 0) | ||
122 | tdone += timer_startval; | ||
123 | } | ||
124 | |||
125 | return timer_ticks_to_usec(tdone); | ||
126 | } | ||
127 | |||
128 | |||
129 | /* | ||
130 | * IRQ handler for the timer | ||
131 | */ | ||
132 | static irqreturn_t | ||
133 | s3c2410_timer_interrupt(int irq, void *dev_id) | ||
134 | { | ||
135 | timer_tick(); | ||
136 | return IRQ_HANDLED; | ||
137 | } | ||
138 | |||
139 | static struct irqaction s3c2410_timer_irq = { | ||
140 | .name = "S3C2410 Timer Tick", | ||
141 | .flags = IRQF_DISABLED | IRQF_TIMER | IRQF_IRQPOLL, | ||
142 | .handler = s3c2410_timer_interrupt, | ||
143 | }; | ||
144 | |||
145 | #define use_tclk1_12() ( \ | ||
146 | machine_is_bast() || \ | ||
147 | machine_is_vr1000() || \ | ||
148 | machine_is_anubis() || \ | ||
149 | machine_is_osiris()) | ||
150 | |||
151 | static struct clk *tin; | ||
152 | static struct clk *tdiv; | ||
153 | static struct clk *timerclk; | ||
154 | |||
155 | /* | ||
156 | * Set up timer interrupt, and return the current time in seconds. | ||
157 | * | ||
158 | * Currently we only use timer4, as it is the only timer which has no | ||
159 | * other function that can be exploited externally | ||
160 | */ | ||
161 | static void s3c2410_timer_setup (void) | ||
162 | { | ||
163 | unsigned long tcon; | ||
164 | unsigned long tcnt; | ||
165 | unsigned long tcfg1; | ||
166 | unsigned long tcfg0; | ||
167 | |||
168 | tcnt = TICK_MAX; /* default value for tcnt */ | ||
169 | |||
170 | /* configure the system for whichever machine is in use */ | ||
171 | |||
172 | if (use_tclk1_12()) { | ||
173 | /* timer is at 12MHz, scaler is 1 */ | ||
174 | timer_usec_ticks = timer_mask_usec_ticks(1, 12000000); | ||
175 | tcnt = 12000000 / HZ; | ||
176 | |||
177 | tcfg1 = __raw_readl(S3C2410_TCFG1); | ||
178 | tcfg1 &= ~S3C2410_TCFG1_MUX4_MASK; | ||
179 | tcfg1 |= S3C2410_TCFG1_MUX4_TCLK1; | ||
180 | __raw_writel(tcfg1, S3C2410_TCFG1); | ||
181 | } else { | ||
182 | unsigned long pclk; | ||
183 | struct clk *tscaler; | ||
184 | |||
185 | /* for the h1940 (and others), we use the pclk from the core | ||
186 | * to generate the timer values. since values around 50 to | ||
187 | * 70MHz are not values we can directly generate the timer | ||
188 | * value from, we need to pre-scale and divide before using it. | ||
189 | * | ||
190 | * for instance, using 50.7MHz and dividing by 6 gives 8.45MHz | ||
191 | * (8.45 ticks per usec) | ||
192 | */ | ||
193 | |||
194 | pclk = clk_get_rate(timerclk); | ||
195 | |||
196 | /* configure clock tick */ | ||
197 | |||
198 | timer_usec_ticks = timer_mask_usec_ticks(6, pclk); | ||
199 | |||
200 | tscaler = clk_get_parent(tdiv); | ||
201 | |||
202 | clk_set_rate(tscaler, pclk / 3); | ||
203 | clk_set_rate(tdiv, pclk / 6); | ||
204 | clk_set_parent(tin, tdiv); | ||
205 | |||
206 | tcnt = clk_get_rate(tin) / HZ; | ||
207 | } | ||
208 | |||
209 | tcon = __raw_readl(S3C2410_TCON); | ||
210 | tcfg0 = __raw_readl(S3C2410_TCFG0); | ||
211 | tcfg1 = __raw_readl(S3C2410_TCFG1); | ||
212 | |||
213 | /* timers reload after counting zero, so reduce the count by 1 */ | ||
214 | |||
215 | tcnt--; | ||
216 | |||
217 | printk(KERN_DEBUG "timer tcon=%08lx, tcnt %04lx, tcfg %08lx,%08lx, usec %08lx\n", | ||
218 | tcon, tcnt, tcfg0, tcfg1, timer_usec_ticks); | ||
219 | |||
220 | /* check to see if timer is within 16bit range... */ | ||
221 | if (tcnt > TICK_MAX) { | ||
222 | panic("setup_timer: HZ is too small, cannot configure timer!"); | ||
223 | return; | ||
224 | } | ||
225 | |||
226 | __raw_writel(tcfg1, S3C2410_TCFG1); | ||
227 | __raw_writel(tcfg0, S3C2410_TCFG0); | ||
228 | |||
229 | timer_startval = tcnt; | ||
230 | __raw_writel(tcnt, S3C2410_TCNTB(4)); | ||
231 | |||
232 | /* ensure timer is stopped... */ | ||
233 | |||
234 | tcon &= ~(7<<20); | ||
235 | tcon |= S3C2410_TCON_T4RELOAD; | ||
236 | tcon |= S3C2410_TCON_T4MANUALUPD; | ||
237 | |||
238 | __raw_writel(tcon, S3C2410_TCON); | ||
239 | __raw_writel(tcnt, S3C2410_TCNTB(4)); | ||
240 | __raw_writel(tcnt, S3C2410_TCMPB(4)); | ||
241 | |||
242 | /* start the timer running */ | ||
243 | tcon |= S3C2410_TCON_T4START; | ||
244 | tcon &= ~S3C2410_TCON_T4MANUALUPD; | ||
245 | __raw_writel(tcon, S3C2410_TCON); | ||
246 | } | ||
247 | |||
248 | static void __init s3c2410_timer_resources(void) | ||
249 | { | ||
250 | struct platform_device tmpdev; | ||
251 | |||
252 | tmpdev.dev.bus = &platform_bus_type; | ||
253 | tmpdev.id = 4; | ||
254 | |||
255 | timerclk = clk_get(NULL, "timers"); | ||
256 | if (IS_ERR(timerclk)) | ||
257 | panic("failed to get clock for system timer"); | ||
258 | |||
259 | clk_enable(timerclk); | ||
260 | |||
261 | if (!use_tclk1_12()) { | ||
262 | tin = clk_get(&tmpdev.dev, "pwm-tin"); | ||
263 | if (IS_ERR(tin)) | ||
264 | panic("failed to get pwm-tin clock for system timer"); | ||
265 | |||
266 | tdiv = clk_get(&tmpdev.dev, "pwm-tdiv"); | ||
267 | if (IS_ERR(tdiv)) | ||
268 | panic("failed to get pwm-tdiv clock for system timer"); | ||
269 | } | ||
270 | |||
271 | clk_enable(tin); | ||
272 | } | ||
273 | |||
274 | static void __init s3c2410_timer_init(void) | ||
275 | { | ||
276 | s3c2410_timer_resources(); | ||
277 | s3c2410_timer_setup(); | ||
278 | setup_irq(IRQ_TIMER4, &s3c2410_timer_irq); | ||
279 | } | ||
280 | |||
281 | struct sys_timer s3c24xx_timer = { | ||
282 | .init = s3c2410_timer_init, | ||
283 | .offset = s3c2410_gettimeoffset, | ||
284 | .resume = s3c2410_timer_setup | ||
285 | }; | ||