diff options
author | Andrew Victor <andrew@sanpeople.com> | 2007-02-05 05:42:07 -0500 |
---|---|---|
committer | Russell King <rmk+kernel@arm.linux.org.uk> | 2007-02-08 09:50:56 -0500 |
commit | 9d0412680e6c7b685ee466842047bcfb924d6dc5 (patch) | |
tree | c79300964ef1aca5d24571696f95e76b37c14679 /arch/arm/mach-at91/pm.c | |
parent | a93d48cc6019f84394b31d10c0d830a3b71696be (diff) |
[ARM] 4124/1: Rename mach-at91rm9200 and arch-at91rm9200 directories
Now that Linux includes support for the Atmel AT91SAM9260 and
AT91SAM9261 processors in addition to the original Atmel AT91RM9200
(with support for more AT91 processors pending), the "mach-at91rm9200"
and "arch-at91rm9200" directories should be renamed to indicate their
more generic nature.
The following git commands should be run BEFORE applying this patch:
git-mv arch/arm/mach-at91rm9200 arch/arm/mach-at91
git-mv include/asm-arm/arch-at91rm9200 include/asm-arm/arch-at91
Signed-off-by: Andrew Victor <andrew@sanpeople.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Diffstat (limited to 'arch/arm/mach-at91/pm.c')
-rw-r--r-- | arch/arm/mach-at91/pm.c | 227 |
1 files changed, 227 insertions, 0 deletions
diff --git a/arch/arm/mach-at91/pm.c b/arch/arm/mach-at91/pm.c new file mode 100644 index 000000000000..e095b1fe8d8a --- /dev/null +++ b/arch/arm/mach-at91/pm.c | |||
@@ -0,0 +1,227 @@ | |||
1 | /* | ||
2 | * arch/arm/mach-at91/pm.c | ||
3 | * AT91 Power Management | ||
4 | * | ||
5 | * Copyright (C) 2005 David Brownell | ||
6 | * | ||
7 | * This program is free software; you can redistribute it and/or modify | ||
8 | * it under the terms of the GNU General Public License as published by | ||
9 | * the Free Software Foundation; either version 2 of the License, or | ||
10 | * (at your option) any later version. | ||
11 | */ | ||
12 | |||
13 | #include <linux/pm.h> | ||
14 | #include <linux/sched.h> | ||
15 | #include <linux/proc_fs.h> | ||
16 | #include <linux/pm.h> | ||
17 | #include <linux/interrupt.h> | ||
18 | #include <linux/sysfs.h> | ||
19 | #include <linux/module.h> | ||
20 | #include <linux/platform_device.h> | ||
21 | |||
22 | #include <asm/io.h> | ||
23 | #include <asm/irq.h> | ||
24 | #include <asm/atomic.h> | ||
25 | #include <asm/mach/time.h> | ||
26 | #include <asm/mach/irq.h> | ||
27 | #include <asm/mach-types.h> | ||
28 | |||
29 | #include <asm/arch/at91_pmc.h> | ||
30 | #include <asm/arch/at91rm9200_mc.h> | ||
31 | #include <asm/arch/gpio.h> | ||
32 | #include <asm/arch/cpu.h> | ||
33 | |||
34 | #include "generic.h" | ||
35 | |||
36 | |||
37 | static int at91_pm_valid_state(suspend_state_t state) | ||
38 | { | ||
39 | switch (state) { | ||
40 | case PM_SUSPEND_ON: | ||
41 | case PM_SUSPEND_STANDBY: | ||
42 | case PM_SUSPEND_MEM: | ||
43 | return 1; | ||
44 | |||
45 | default: | ||
46 | return 0; | ||
47 | } | ||
48 | } | ||
49 | |||
50 | |||
51 | static suspend_state_t target_state; | ||
52 | |||
53 | /* | ||
54 | * Called after processes are frozen, but before we shutdown devices. | ||
55 | */ | ||
56 | static int at91_pm_prepare(suspend_state_t state) | ||
57 | { | ||
58 | target_state = state; | ||
59 | return 0; | ||
60 | } | ||
61 | |||
62 | /* | ||
63 | * Verify that all the clocks are correct before entering | ||
64 | * slow-clock mode. | ||
65 | */ | ||
66 | static int at91_pm_verify_clocks(void) | ||
67 | { | ||
68 | unsigned long scsr; | ||
69 | int i; | ||
70 | |||
71 | scsr = at91_sys_read(AT91_PMC_SCSR); | ||
72 | |||
73 | /* USB must not be using PLLB */ | ||
74 | if (cpu_is_at91rm9200()) { | ||
75 | if ((scsr & (AT91RM9200_PMC_UHP | AT91RM9200_PMC_UDP)) != 0) { | ||
76 | pr_debug("AT91: PM - Suspend-to-RAM with USB still active\n"); | ||
77 | return 0; | ||
78 | } | ||
79 | } else if (cpu_is_at91sam9260()) { | ||
80 | #warning "Check SAM9260 USB clocks" | ||
81 | } else if (cpu_is_at91sam9261()) { | ||
82 | #warning "Check SAM9261 USB clocks" | ||
83 | } | ||
84 | |||
85 | #ifdef CONFIG_AT91_PROGRAMMABLE_CLOCKS | ||
86 | /* PCK0..PCK3 must be disabled, or configured to use clk32k */ | ||
87 | for (i = 0; i < 4; i++) { | ||
88 | u32 css; | ||
89 | |||
90 | if ((scsr & (AT91_PMC_PCK0 << i)) == 0) | ||
91 | continue; | ||
92 | |||
93 | css = at91_sys_read(AT91_PMC_PCKR(i)) & AT91_PMC_CSS; | ||
94 | if (css != AT91_PMC_CSS_SLOW) { | ||
95 | pr_debug("AT91: PM - Suspend-to-RAM with PCK%d src %d\n", i, css); | ||
96 | return 0; | ||
97 | } | ||
98 | } | ||
99 | #endif | ||
100 | |||
101 | return 1; | ||
102 | } | ||
103 | |||
104 | /* | ||
105 | * Call this from platform driver suspend() to see how deeply to suspend. | ||
106 | * For example, some controllers (like OHCI) need one of the PLL clocks | ||
107 | * in order to act as a wakeup source, and those are not available when | ||
108 | * going into slow clock mode. | ||
109 | * | ||
110 | * REVISIT: generalize as clk_will_be_available(clk)? Other platforms have | ||
111 | * the very same problem (but not using at91 main_clk), and it'd be better | ||
112 | * to add one generic API rather than lots of platform-specific ones. | ||
113 | */ | ||
114 | int at91_suspend_entering_slow_clock(void) | ||
115 | { | ||
116 | return (target_state == PM_SUSPEND_MEM); | ||
117 | } | ||
118 | EXPORT_SYMBOL(at91_suspend_entering_slow_clock); | ||
119 | |||
120 | |||
121 | static void (*slow_clock)(void); | ||
122 | |||
123 | |||
124 | static int at91_pm_enter(suspend_state_t state) | ||
125 | { | ||
126 | at91_gpio_suspend(); | ||
127 | at91_irq_suspend(); | ||
128 | |||
129 | pr_debug("AT91: PM - wake mask %08x, pm state %d\n", | ||
130 | /* remember all the always-wake irqs */ | ||
131 | (at91_sys_read(AT91_PMC_PCSR) | ||
132 | | (1 << AT91_ID_FIQ) | ||
133 | | (1 << AT91_ID_SYS) | ||
134 | | (at91_extern_irq)) | ||
135 | & at91_sys_read(AT91_AIC_IMR), | ||
136 | state); | ||
137 | |||
138 | switch (state) { | ||
139 | /* | ||
140 | * Suspend-to-RAM is like STANDBY plus slow clock mode, so | ||
141 | * drivers must suspend more deeply: only the master clock | ||
142 | * controller may be using the main oscillator. | ||
143 | */ | ||
144 | case PM_SUSPEND_MEM: | ||
145 | /* | ||
146 | * Ensure that clocks are in a valid state. | ||
147 | */ | ||
148 | if (!at91_pm_verify_clocks()) | ||
149 | goto error; | ||
150 | |||
151 | /* | ||
152 | * Enter slow clock mode by switching over to clk32k and | ||
153 | * turning off the main oscillator; reverse on wakeup. | ||
154 | */ | ||
155 | if (slow_clock) { | ||
156 | slow_clock(); | ||
157 | break; | ||
158 | } else { | ||
159 | /* DEVELOPMENT ONLY */ | ||
160 | pr_info("AT91: PM - no slow clock mode yet ...\n"); | ||
161 | /* FALLTHROUGH leaving master clock alone */ | ||
162 | } | ||
163 | |||
164 | /* | ||
165 | * STANDBY mode has *all* drivers suspended; ignores irqs not | ||
166 | * marked as 'wakeup' event sources; and reduces DRAM power. | ||
167 | * But otherwise it's identical to PM_SUSPEND_ON: cpu idle, and | ||
168 | * nothing fancy done with main or cpu clocks. | ||
169 | */ | ||
170 | case PM_SUSPEND_STANDBY: | ||
171 | /* | ||
172 | * NOTE: the Wait-for-Interrupt instruction needs to be | ||
173 | * in icache so the SDRAM stays in self-refresh mode until | ||
174 | * the wakeup IRQ occurs. | ||
175 | */ | ||
176 | asm("b 1f; .align 5; 1:"); | ||
177 | asm("mcr p15, 0, r0, c7, c10, 4"); /* drain write buffer */ | ||
178 | at91_sys_write(AT91_SDRAMC_SRR, 1); /* self-refresh mode */ | ||
179 | /* fall though to next state */ | ||
180 | |||
181 | case PM_SUSPEND_ON: | ||
182 | asm("mcr p15, 0, r0, c7, c0, 4"); /* wait for interrupt */ | ||
183 | break; | ||
184 | |||
185 | default: | ||
186 | pr_debug("AT91: PM - bogus suspend state %d\n", state); | ||
187 | goto error; | ||
188 | } | ||
189 | |||
190 | pr_debug("AT91: PM - wakeup %08x\n", | ||
191 | at91_sys_read(AT91_AIC_IPR) & at91_sys_read(AT91_AIC_IMR)); | ||
192 | |||
193 | error: | ||
194 | target_state = PM_SUSPEND_ON; | ||
195 | at91_irq_resume(); | ||
196 | at91_gpio_resume(); | ||
197 | return 0; | ||
198 | } | ||
199 | |||
200 | |||
201 | static struct pm_ops at91_pm_ops ={ | ||
202 | .pm_disk_mode = 0, | ||
203 | .valid = at91_pm_valid_state, | ||
204 | .prepare = at91_pm_prepare, | ||
205 | .enter = at91_pm_enter, | ||
206 | }; | ||
207 | |||
208 | static int __init at91_pm_init(void) | ||
209 | { | ||
210 | printk("AT91: Power Management\n"); | ||
211 | |||
212 | #ifdef CONFIG_AT91_PM_SLOW_CLOCK | ||
213 | /* REVISIT allocations of SRAM should be dynamically managed. | ||
214 | * FIQ handlers and other components will want SRAM/TCM too... | ||
215 | */ | ||
216 | slow_clock = (void *) (AT91_VA_BASE_SRAM + (3 * SZ_4K)); | ||
217 | memcpy(slow_clock, at91rm9200_slow_clock, at91rm9200_slow_clock_sz); | ||
218 | #endif | ||
219 | |||
220 | /* Disable SDRAM low-power mode. Cannot be used with self-refresh. */ | ||
221 | at91_sys_write(AT91_SDRAMC_LPR, 0); | ||
222 | |||
223 | pm_set_ops(&at91_pm_ops); | ||
224 | |||
225 | return 0; | ||
226 | } | ||
227 | arch_initcall(at91_pm_init); | ||