Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs...
[sfrench/cifs-2.6.git] / arch / arm / mach-omap2 / pm24xx.c
1 /*
2  * OMAP2 Power Management Routines
3  *
4  * Copyright (C) 2005 Texas Instruments, Inc.
5  * Copyright (C) 2006-2008 Nokia Corporation
6  *
7  * Written by:
8  * Richard Woodruff <r-woodruff2@ti.com>
9  * Tony Lindgren
10  * Juha Yrjola
11  * Amit Kucheria <amit.kucheria@nokia.com>
12  * Igor Stoppa <igor.stoppa@nokia.com>
13  *
14  * Based on pm.c for omap1
15  *
16  * This program is free software; you can redistribute it and/or modify
17  * it under the terms of the GNU General Public License version 2 as
18  * published by the Free Software Foundation.
19  */
20
21 #include <linux/suspend.h>
22 #include <linux/sched.h>
23 #include <linux/proc_fs.h>
24 #include <linux/interrupt.h>
25 #include <linux/sysfs.h>
26 #include <linux/module.h>
27 #include <linux/delay.h>
28 #include <linux/clk.h>
29 #include <linux/io.h>
30 #include <linux/irq.h>
31 #include <linux/time.h>
32 #include <linux/gpio.h>
33 #include <linux/console.h>
34
35 #include <asm/mach/time.h>
36 #include <asm/mach/irq.h>
37 #include <asm/mach-types.h>
38
39 #include <mach/irqs.h>
40 #include <plat/clock.h>
41 #include <plat/sram.h>
42 #include <plat/dma.h>
43 #include <plat/board.h>
44
45 #include "prm2xxx_3xxx.h"
46 #include "prm-regbits-24xx.h"
47 #include "cm2xxx_3xxx.h"
48 #include "cm-regbits-24xx.h"
49 #include "sdrc.h"
50 #include "pm.h"
51 #include "control.h"
52
53 #include "powerdomain.h"
54 #include "clockdomain.h"
55
56 #ifdef CONFIG_SUSPEND
57 static suspend_state_t suspend_state = PM_SUSPEND_ON;
58 static inline bool is_suspending(void)
59 {
60         return (suspend_state != PM_SUSPEND_ON);
61 }
62 #else
63 static inline bool is_suspending(void)
64 {
65         return false;
66 }
67 #endif
68
69 static void (*omap2_sram_idle)(void);
70 static void (*omap2_sram_suspend)(u32 dllctrl, void __iomem *sdrc_dlla_ctrl,
71                                   void __iomem *sdrc_power);
72
73 static struct powerdomain *mpu_pwrdm, *core_pwrdm;
74 static struct clockdomain *dsp_clkdm, *mpu_clkdm, *wkup_clkdm, *gfx_clkdm;
75
76 static struct clk *osc_ck, *emul_ck;
77
78 static int omap2_fclks_active(void)
79 {
80         u32 f1, f2;
81
82         f1 = omap2_cm_read_mod_reg(CORE_MOD, CM_FCLKEN1);
83         f2 = omap2_cm_read_mod_reg(CORE_MOD, OMAP24XX_CM_FCLKEN2);
84
85         /* Ignore UART clocks.  These are handled by UART core (serial.c) */
86         f1 &= ~(OMAP24XX_EN_UART1_MASK | OMAP24XX_EN_UART2_MASK);
87         f2 &= ~OMAP24XX_EN_UART3_MASK;
88
89         if (f1 | f2)
90                 return 1;
91         return 0;
92 }
93
94 static void omap2_enter_full_retention(void)
95 {
96         u32 l;
97         struct timespec ts_preidle, ts_postidle, ts_idle;
98
99         /* There is 1 reference hold for all children of the oscillator
100          * clock, the following will remove it. If no one else uses the
101          * oscillator itself it will be disabled if/when we enter retention
102          * mode.
103          */
104         clk_disable(osc_ck);
105
106         /* Clear old wake-up events */
107         /* REVISIT: These write to reserved bits? */
108         omap2_prm_write_mod_reg(0xffffffff, CORE_MOD, PM_WKST1);
109         omap2_prm_write_mod_reg(0xffffffff, CORE_MOD, OMAP24XX_PM_WKST2);
110         omap2_prm_write_mod_reg(0xffffffff, WKUP_MOD, PM_WKST);
111
112         /*
113          * Set MPU powerdomain's next power state to RETENTION;
114          * preserve logic state during retention
115          */
116         pwrdm_set_logic_retst(mpu_pwrdm, PWRDM_POWER_RET);
117         pwrdm_set_next_pwrst(mpu_pwrdm, PWRDM_POWER_RET);
118
119         /* Workaround to kill USB */
120         l = omap_ctrl_readl(OMAP2_CONTROL_DEVCONF0) | OMAP24XX_USBSTANDBYCTRL;
121         omap_ctrl_writel(l, OMAP2_CONTROL_DEVCONF0);
122
123         omap2_gpio_prepare_for_idle(0);
124
125         if (omap2_pm_debug) {
126                 omap2_pm_dump(0, 0, 0);
127                 getnstimeofday(&ts_preidle);
128         }
129
130         /* One last check for pending IRQs to avoid extra latency due
131          * to sleeping unnecessarily. */
132         if (omap_irq_pending())
133                 goto no_sleep;
134
135         /* Block console output in case it is on one of the OMAP UARTs */
136         if (!is_suspending())
137                 if (!console_trylock())
138                         goto no_sleep;
139
140         omap_uart_prepare_idle(0);
141         omap_uart_prepare_idle(1);
142         omap_uart_prepare_idle(2);
143
144         /* Jump to SRAM suspend code */
145         omap2_sram_suspend(sdrc_read_reg(SDRC_DLLA_CTRL),
146                            OMAP_SDRC_REGADDR(SDRC_DLLA_CTRL),
147                            OMAP_SDRC_REGADDR(SDRC_POWER));
148
149         omap_uart_resume_idle(2);
150         omap_uart_resume_idle(1);
151         omap_uart_resume_idle(0);
152
153         if (!is_suspending())
154                 console_unlock();
155
156 no_sleep:
157         if (omap2_pm_debug) {
158                 unsigned long long tmp;
159
160                 getnstimeofday(&ts_postidle);
161                 ts_idle = timespec_sub(ts_postidle, ts_preidle);
162                 tmp = timespec_to_ns(&ts_idle) * NSEC_PER_USEC;
163                 omap2_pm_dump(0, 1, tmp);
164         }
165         omap2_gpio_resume_after_idle();
166
167         clk_enable(osc_ck);
168
169         /* clear CORE wake-up events */
170         omap2_prm_write_mod_reg(0xffffffff, CORE_MOD, PM_WKST1);
171         omap2_prm_write_mod_reg(0xffffffff, CORE_MOD, OMAP24XX_PM_WKST2);
172
173         /* wakeup domain events - bit 1: GPT1, bit5 GPIO */
174         omap2_prm_clear_mod_reg_bits(0x4 | 0x1, WKUP_MOD, PM_WKST);
175
176         /* MPU domain wake events */
177         l = omap2_prm_read_mod_reg(OCP_MOD, OMAP2_PRCM_IRQSTATUS_MPU_OFFSET);
178         if (l & 0x01)
179                 omap2_prm_write_mod_reg(0x01, OCP_MOD,
180                                   OMAP2_PRCM_IRQSTATUS_MPU_OFFSET);
181         if (l & 0x20)
182                 omap2_prm_write_mod_reg(0x20, OCP_MOD,
183                                   OMAP2_PRCM_IRQSTATUS_MPU_OFFSET);
184
185         /* Mask future PRCM-to-MPU interrupts */
186         omap2_prm_write_mod_reg(0x0, OCP_MOD, OMAP2_PRCM_IRQSTATUS_MPU_OFFSET);
187 }
188
189 static int omap2_i2c_active(void)
190 {
191         u32 l;
192
193         l = omap2_cm_read_mod_reg(CORE_MOD, CM_FCLKEN1);
194         return l & (OMAP2420_EN_I2C2_MASK | OMAP2420_EN_I2C1_MASK);
195 }
196
197 static int sti_console_enabled;
198
199 static int omap2_allow_mpu_retention(void)
200 {
201         u32 l;
202
203         /* Check for MMC, UART2, UART1, McSPI2, McSPI1 and DSS1. */
204         l = omap2_cm_read_mod_reg(CORE_MOD, CM_FCLKEN1);
205         if (l & (OMAP2420_EN_MMC_MASK | OMAP24XX_EN_UART2_MASK |
206                  OMAP24XX_EN_UART1_MASK | OMAP24XX_EN_MCSPI2_MASK |
207                  OMAP24XX_EN_MCSPI1_MASK | OMAP24XX_EN_DSS1_MASK))
208                 return 0;
209         /* Check for UART3. */
210         l = omap2_cm_read_mod_reg(CORE_MOD, OMAP24XX_CM_FCLKEN2);
211         if (l & OMAP24XX_EN_UART3_MASK)
212                 return 0;
213         if (sti_console_enabled)
214                 return 0;
215
216         return 1;
217 }
218
219 static void omap2_enter_mpu_retention(void)
220 {
221         int only_idle = 0;
222         struct timespec ts_preidle, ts_postidle, ts_idle;
223
224         /* Putting MPU into the WFI state while a transfer is active
225          * seems to cause the I2C block to timeout. Why? Good question. */
226         if (omap2_i2c_active())
227                 return;
228
229         /* The peripherals seem not to be able to wake up the MPU when
230          * it is in retention mode. */
231         if (omap2_allow_mpu_retention()) {
232                 /* REVISIT: These write to reserved bits? */
233                 omap2_prm_write_mod_reg(0xffffffff, CORE_MOD, PM_WKST1);
234                 omap2_prm_write_mod_reg(0xffffffff, CORE_MOD, OMAP24XX_PM_WKST2);
235                 omap2_prm_write_mod_reg(0xffffffff, WKUP_MOD, PM_WKST);
236
237                 /* Try to enter MPU retention */
238                 omap2_prm_write_mod_reg((0x01 << OMAP_POWERSTATE_SHIFT) |
239                                   OMAP_LOGICRETSTATE_MASK,
240                                   MPU_MOD, OMAP2_PM_PWSTCTRL);
241         } else {
242                 /* Block MPU retention */
243
244                 omap2_prm_write_mod_reg(OMAP_LOGICRETSTATE_MASK, MPU_MOD,
245                                                  OMAP2_PM_PWSTCTRL);
246                 only_idle = 1;
247         }
248
249         if (omap2_pm_debug) {
250                 omap2_pm_dump(only_idle ? 2 : 1, 0, 0);
251                 getnstimeofday(&ts_preidle);
252         }
253
254         omap2_sram_idle();
255
256         if (omap2_pm_debug) {
257                 unsigned long long tmp;
258
259                 getnstimeofday(&ts_postidle);
260                 ts_idle = timespec_sub(ts_postidle, ts_preidle);
261                 tmp = timespec_to_ns(&ts_idle) * NSEC_PER_USEC;
262                 omap2_pm_dump(only_idle ? 2 : 1, 1, tmp);
263         }
264 }
265
266 static int omap2_can_sleep(void)
267 {
268         if (omap2_fclks_active())
269                 return 0;
270         if (!omap_uart_can_sleep())
271                 return 0;
272         if (osc_ck->usecount > 1)
273                 return 0;
274         if (omap_dma_running())
275                 return 0;
276
277         return 1;
278 }
279
280 static void omap2_pm_idle(void)
281 {
282         local_irq_disable();
283         local_fiq_disable();
284
285         if (!omap2_can_sleep()) {
286                 if (omap_irq_pending())
287                         goto out;
288                 omap2_enter_mpu_retention();
289                 goto out;
290         }
291
292         if (omap_irq_pending())
293                 goto out;
294
295         omap2_enter_full_retention();
296
297 out:
298         local_fiq_enable();
299         local_irq_enable();
300 }
301
302 #ifdef CONFIG_SUSPEND
303 static int omap2_pm_begin(suspend_state_t state)
304 {
305         disable_hlt();
306         suspend_state = state;
307         return 0;
308 }
309
310 static int omap2_pm_suspend(void)
311 {
312         u32 wken_wkup, mir1;
313
314         wken_wkup = omap2_prm_read_mod_reg(WKUP_MOD, PM_WKEN);
315         wken_wkup &= ~OMAP24XX_EN_GPT1_MASK;
316         omap2_prm_write_mod_reg(wken_wkup, WKUP_MOD, PM_WKEN);
317
318         /* Mask GPT1 */
319         mir1 = omap_readl(0x480fe0a4);
320         omap_writel(1 << 5, 0x480fe0ac);
321
322         omap_uart_prepare_suspend();
323         omap2_enter_full_retention();
324
325         omap_writel(mir1, 0x480fe0a4);
326         omap2_prm_write_mod_reg(wken_wkup, WKUP_MOD, PM_WKEN);
327
328         return 0;
329 }
330
331 static int omap2_pm_enter(suspend_state_t state)
332 {
333         int ret = 0;
334
335         switch (state) {
336         case PM_SUSPEND_STANDBY:
337         case PM_SUSPEND_MEM:
338                 ret = omap2_pm_suspend();
339                 break;
340         default:
341                 ret = -EINVAL;
342         }
343
344         return ret;
345 }
346
347 static void omap2_pm_end(void)
348 {
349         suspend_state = PM_SUSPEND_ON;
350         enable_hlt();
351 }
352
353 static const struct platform_suspend_ops omap_pm_ops = {
354         .begin          = omap2_pm_begin,
355         .enter          = omap2_pm_enter,
356         .end            = omap2_pm_end,
357         .valid          = suspend_valid_only_mem,
358 };
359 #else
360 static const struct platform_suspend_ops __initdata omap_pm_ops;
361 #endif /* CONFIG_SUSPEND */
362
363 /* XXX This function should be shareable between OMAP2xxx and OMAP3 */
364 static int __init clkdms_setup(struct clockdomain *clkdm, void *unused)
365 {
366         if (clkdm->flags & CLKDM_CAN_ENABLE_AUTO)
367                 clkdm_allow_idle(clkdm);
368         else if (clkdm->flags & CLKDM_CAN_FORCE_SLEEP &&
369                  atomic_read(&clkdm->usecount) == 0)
370                 clkdm_sleep(clkdm);
371         return 0;
372 }
373
374 static void __init prcm_setup_regs(void)
375 {
376         int i, num_mem_banks;
377         struct powerdomain *pwrdm;
378
379         /*
380          * Enable autoidle
381          * XXX This should be handled by hwmod code or PRCM init code
382          */
383         omap2_prm_write_mod_reg(OMAP24XX_AUTOIDLE_MASK, OCP_MOD,
384                           OMAP2_PRCM_SYSCONFIG_OFFSET);
385
386         /*
387          * Set CORE powerdomain memory banks to retain their contents
388          * during RETENTION
389          */
390         num_mem_banks = pwrdm_get_mem_bank_count(core_pwrdm);
391         for (i = 0; i < num_mem_banks; i++)
392                 pwrdm_set_mem_retst(core_pwrdm, i, PWRDM_POWER_RET);
393
394         /* Set CORE powerdomain's next power state to RETENTION */
395         pwrdm_set_next_pwrst(core_pwrdm, PWRDM_POWER_RET);
396
397         /*
398          * Set MPU powerdomain's next power state to RETENTION;
399          * preserve logic state during retention
400          */
401         pwrdm_set_logic_retst(mpu_pwrdm, PWRDM_POWER_RET);
402         pwrdm_set_next_pwrst(mpu_pwrdm, PWRDM_POWER_RET);
403
404         /* Force-power down DSP, GFX powerdomains */
405
406         pwrdm = clkdm_get_pwrdm(dsp_clkdm);
407         pwrdm_set_next_pwrst(pwrdm, PWRDM_POWER_OFF);
408         clkdm_sleep(dsp_clkdm);
409
410         pwrdm = clkdm_get_pwrdm(gfx_clkdm);
411         pwrdm_set_next_pwrst(pwrdm, PWRDM_POWER_OFF);
412         clkdm_sleep(gfx_clkdm);
413
414         /* Enable hardware-supervised idle for all clkdms */
415         clkdm_for_each(clkdms_setup, NULL);
416         clkdm_add_wkdep(mpu_clkdm, wkup_clkdm);
417
418         /* REVISIT: Configure number of 32 kHz clock cycles for sys_clk
419          * stabilisation */
420         omap2_prm_write_mod_reg(15 << OMAP_SETUP_TIME_SHIFT, OMAP24XX_GR_MOD,
421                                 OMAP2_PRCM_CLKSSETUP_OFFSET);
422
423         /* Configure automatic voltage transition */
424         omap2_prm_write_mod_reg(2 << OMAP_SETUP_TIME_SHIFT, OMAP24XX_GR_MOD,
425                                 OMAP2_PRCM_VOLTSETUP_OFFSET);
426         omap2_prm_write_mod_reg(OMAP24XX_AUTO_EXTVOLT_MASK |
427                                 (0x1 << OMAP24XX_SETOFF_LEVEL_SHIFT) |
428                                 OMAP24XX_MEMRETCTRL_MASK |
429                                 (0x1 << OMAP24XX_SETRET_LEVEL_SHIFT) |
430                                 (0x0 << OMAP24XX_VOLT_LEVEL_SHIFT),
431                                 OMAP24XX_GR_MOD, OMAP2_PRCM_VOLTCTRL_OFFSET);
432
433         /* Enable wake-up events */
434         omap2_prm_write_mod_reg(OMAP24XX_EN_GPIOS_MASK | OMAP24XX_EN_GPT1_MASK,
435                                 WKUP_MOD, PM_WKEN);
436 }
437
438 static int __init omap2_pm_init(void)
439 {
440         u32 l;
441
442         if (!cpu_is_omap24xx())
443                 return -ENODEV;
444
445         printk(KERN_INFO "Power Management for OMAP2 initializing\n");
446         l = omap2_prm_read_mod_reg(OCP_MOD, OMAP2_PRCM_REVISION_OFFSET);
447         printk(KERN_INFO "PRCM revision %d.%d\n", (l >> 4) & 0x0f, l & 0x0f);
448
449         /* Look up important powerdomains */
450
451         mpu_pwrdm = pwrdm_lookup("mpu_pwrdm");
452         if (!mpu_pwrdm)
453                 pr_err("PM: mpu_pwrdm not found\n");
454
455         core_pwrdm = pwrdm_lookup("core_pwrdm");
456         if (!core_pwrdm)
457                 pr_err("PM: core_pwrdm not found\n");
458
459         /* Look up important clockdomains */
460
461         mpu_clkdm = clkdm_lookup("mpu_clkdm");
462         if (!mpu_clkdm)
463                 pr_err("PM: mpu_clkdm not found\n");
464
465         wkup_clkdm = clkdm_lookup("wkup_clkdm");
466         if (!wkup_clkdm)
467                 pr_err("PM: wkup_clkdm not found\n");
468
469         dsp_clkdm = clkdm_lookup("dsp_clkdm");
470         if (!dsp_clkdm)
471                 pr_err("PM: dsp_clkdm not found\n");
472
473         gfx_clkdm = clkdm_lookup("gfx_clkdm");
474         if (!gfx_clkdm)
475                 pr_err("PM: gfx_clkdm not found\n");
476
477
478         osc_ck = clk_get(NULL, "osc_ck");
479         if (IS_ERR(osc_ck)) {
480                 printk(KERN_ERR "could not get osc_ck\n");
481                 return -ENODEV;
482         }
483
484         if (cpu_is_omap242x()) {
485                 emul_ck = clk_get(NULL, "emul_ck");
486                 if (IS_ERR(emul_ck)) {
487                         printk(KERN_ERR "could not get emul_ck\n");
488                         clk_put(osc_ck);
489                         return -ENODEV;
490                 }
491         }
492
493         prcm_setup_regs();
494
495         /* Hack to prevent MPU retention when STI console is enabled. */
496         {
497                 const struct omap_sti_console_config *sti;
498
499                 sti = omap_get_config(OMAP_TAG_STI_CONSOLE,
500                                       struct omap_sti_console_config);
501                 if (sti != NULL && sti->enable)
502                         sti_console_enabled = 1;
503         }
504
505         /*
506          * We copy the assembler sleep/wakeup routines to SRAM.
507          * These routines need to be in SRAM as that's the only
508          * memory the MPU can see when it wakes up.
509          */
510         if (cpu_is_omap24xx()) {
511                 omap2_sram_idle = omap_sram_push(omap24xx_idle_loop_suspend,
512                                                  omap24xx_idle_loop_suspend_sz);
513
514                 omap2_sram_suspend = omap_sram_push(omap24xx_cpu_suspend,
515                                                     omap24xx_cpu_suspend_sz);
516         }
517
518         suspend_set_ops(&omap_pm_ops);
519         pm_idle = omap2_pm_idle;
520
521         return 0;
522 }
523
524 late_initcall(omap2_pm_init);