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1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * OMAP2 Power Management Routines
4  *
5  * Copyright (C) 2005 Texas Instruments, Inc.
6  * Copyright (C) 2006-2008 Nokia Corporation
7  *
8  * Written by:
9  * Richard Woodruff <r-woodruff2@ti.com>
10  * Tony Lindgren
11  * Juha Yrjola
12  * Amit Kucheria <amit.kucheria@nokia.com>
13  * Igor Stoppa <igor.stoppa@nokia.com>
14  *
15  * Based on pm.c for omap1
16  */
17 
18 #include <linux/cpu_pm.h>
19 #include <linux/suspend.h>
20 #include <linux/sched.h>
21 #include <linux/proc_fs.h>
22 #include <linux/interrupt.h>
23 #include <linux/sysfs.h>
24 #include <linux/module.h>
25 #include <linux/delay.h>
26 #include <linux/clk.h>
27 #include <linux/clk-provider.h>
28 #include <linux/irq.h>
29 #include <linux/time.h>
30 
31 #include <asm/fncpy.h>
32 
33 #include <asm/mach/time.h>
34 #include <asm/mach/irq.h>
35 #include <asm/mach-types.h>
36 #include <asm/system_misc.h>
37 
38 #include <linux/omap-dma.h>
39 
40 #include "soc.h"
41 #include "common.h"
42 #include "clock.h"
43 #include "prm2xxx.h"
44 #include "prm-regbits-24xx.h"
45 #include "cm2xxx.h"
46 #include "cm-regbits-24xx.h"
47 #include "sdrc.h"
48 #include "sram.h"
49 #include "pm.h"
50 #include "control.h"
51 #include "powerdomain.h"
52 #include "clockdomain.h"
53 
54 static void (*omap2_sram_suspend)(u32 dllctrl, void __iomem *sdrc_dlla_ctrl,
55 				  void __iomem *sdrc_power);
56 
57 static struct powerdomain *mpu_pwrdm, *core_pwrdm;
58 static struct clockdomain *dsp_clkdm, *mpu_clkdm, *wkup_clkdm, *gfx_clkdm;
59 
60 static struct clk *osc_ck, *emul_ck;
61 
omap2_enter_full_retention(void)62 static int omap2_enter_full_retention(void)
63 {
64 	u32 l;
65 
66 	/* There is 1 reference hold for all children of the oscillator
67 	 * clock, the following will remove it. If no one else uses the
68 	 * oscillator itself it will be disabled if/when we enter retention
69 	 * mode.
70 	 */
71 	clk_disable(osc_ck);
72 
73 	/* Clear old wake-up events */
74 	/* REVISIT: These write to reserved bits? */
75 	omap_prm_clear_mod_irqs(CORE_MOD, PM_WKST1, ~0);
76 	omap_prm_clear_mod_irqs(CORE_MOD, OMAP24XX_PM_WKST2, ~0);
77 	omap_prm_clear_mod_irqs(WKUP_MOD, PM_WKST, ~0);
78 
79 	pwrdm_set_next_pwrst(core_pwrdm, PWRDM_POWER_RET);
80 	pwrdm_set_next_pwrst(mpu_pwrdm, PWRDM_POWER_RET);
81 
82 	/* Workaround to kill USB */
83 	l = omap_ctrl_readl(OMAP2_CONTROL_DEVCONF0) | OMAP24XX_USBSTANDBYCTRL;
84 	omap_ctrl_writel(l, OMAP2_CONTROL_DEVCONF0);
85 
86 	/* One last check for pending IRQs to avoid extra latency due
87 	 * to sleeping unnecessarily. */
88 	if (omap_irq_pending())
89 		goto no_sleep;
90 
91 	/* Jump to SRAM suspend code */
92 	omap2_sram_suspend(sdrc_read_reg(SDRC_DLLA_CTRL),
93 			   OMAP_SDRC_REGADDR(SDRC_DLLA_CTRL),
94 			   OMAP_SDRC_REGADDR(SDRC_POWER));
95 
96 no_sleep:
97 	clk_enable(osc_ck);
98 
99 	/* clear CORE wake-up events */
100 	omap_prm_clear_mod_irqs(CORE_MOD, PM_WKST1, ~0);
101 	omap_prm_clear_mod_irqs(CORE_MOD, OMAP24XX_PM_WKST2, ~0);
102 
103 	/* wakeup domain events - bit 1: GPT1, bit5 GPIO */
104 	omap_prm_clear_mod_irqs(WKUP_MOD, PM_WKST, 0x4 | 0x1);
105 
106 	/* MPU domain wake events */
107 	omap_prm_clear_mod_irqs(OCP_MOD, OMAP2_PRCM_IRQSTATUS_MPU_OFFSET, 0x1);
108 
109 	omap_prm_clear_mod_irqs(OCP_MOD, OMAP2_PRCM_IRQSTATUS_MPU_OFFSET, 0x20);
110 
111 	pwrdm_set_next_pwrst(mpu_pwrdm, PWRDM_POWER_ON);
112 	pwrdm_set_next_pwrst(core_pwrdm, PWRDM_POWER_ON);
113 
114 	return 0;
115 }
116 
117 static int sti_console_enabled;
118 
omap2_allow_mpu_retention(void)119 static int omap2_allow_mpu_retention(void)
120 {
121 	if (!omap2xxx_cm_mpu_retention_allowed())
122 		return 0;
123 	if (sti_console_enabled)
124 		return 0;
125 
126 	return 1;
127 }
128 
omap2_enter_mpu_retention(void)129 static void omap2_enter_mpu_retention(void)
130 {
131 	const int zero = 0;
132 
133 	/* The peripherals seem not to be able to wake up the MPU when
134 	 * it is in retention mode. */
135 	if (omap2_allow_mpu_retention()) {
136 		/* REVISIT: These write to reserved bits? */
137 		omap_prm_clear_mod_irqs(CORE_MOD, PM_WKST1, ~0);
138 		omap_prm_clear_mod_irqs(CORE_MOD, OMAP24XX_PM_WKST2, ~0);
139 		omap_prm_clear_mod_irqs(WKUP_MOD, PM_WKST, ~0);
140 
141 		/* Try to enter MPU retention */
142 		pwrdm_set_next_pwrst(mpu_pwrdm, PWRDM_POWER_RET);
143 
144 	} else {
145 		/* Block MPU retention */
146 		pwrdm_set_next_pwrst(mpu_pwrdm, PWRDM_POWER_ON);
147 	}
148 
149 	/* WFI */
150 	asm("mcr p15, 0, %0, c7, c0, 4" : : "r" (zero) : "memory", "cc");
151 
152 	pwrdm_set_next_pwrst(mpu_pwrdm, PWRDM_POWER_ON);
153 }
154 
omap2_can_sleep(void)155 static int omap2_can_sleep(void)
156 {
157 	if (omap2xxx_cm_fclks_active())
158 		return 0;
159 	if (__clk_is_enabled(osc_ck))
160 		return 0;
161 
162 	return 1;
163 }
164 
omap2_pm_idle(void)165 static void omap2_pm_idle(void)
166 {
167 	int error;
168 
169 	if (omap_irq_pending())
170 		return;
171 
172 	error = cpu_cluster_pm_enter();
173 	if (error || !omap2_can_sleep()) {
174 		omap2_enter_mpu_retention();
175 		goto out_cpu_cluster_pm;
176 	}
177 
178 	omap2_enter_full_retention();
179 
180 out_cpu_cluster_pm:
181 	cpu_cluster_pm_exit();
182 }
183 
prcm_setup_regs(void)184 static void __init prcm_setup_regs(void)
185 {
186 	int i, num_mem_banks;
187 	struct powerdomain *pwrdm;
188 
189 	/*
190 	 * Enable autoidle
191 	 * XXX This should be handled by hwmod code or PRCM init code
192 	 */
193 	omap2_prm_write_mod_reg(OMAP24XX_AUTOIDLE_MASK, OCP_MOD,
194 			  OMAP2_PRCM_SYSCONFIG_OFFSET);
195 
196 	/*
197 	 * Set CORE powerdomain memory banks to retain their contents
198 	 * during RETENTION
199 	 */
200 	num_mem_banks = pwrdm_get_mem_bank_count(core_pwrdm);
201 	for (i = 0; i < num_mem_banks; i++)
202 		pwrdm_set_mem_retst(core_pwrdm, i, PWRDM_POWER_RET);
203 
204 	pwrdm_set_logic_retst(core_pwrdm, PWRDM_POWER_RET);
205 
206 	pwrdm_set_logic_retst(mpu_pwrdm, PWRDM_POWER_RET);
207 
208 	/* Force-power down DSP, GFX powerdomains */
209 
210 	pwrdm = clkdm_get_pwrdm(dsp_clkdm);
211 	pwrdm_set_next_pwrst(pwrdm, PWRDM_POWER_OFF);
212 
213 	pwrdm = clkdm_get_pwrdm(gfx_clkdm);
214 	pwrdm_set_next_pwrst(pwrdm, PWRDM_POWER_OFF);
215 
216 	/* Enable hardware-supervised idle for all clkdms */
217 	clkdm_for_each(omap_pm_clkdms_setup, NULL);
218 	clkdm_add_wkdep(mpu_clkdm, wkup_clkdm);
219 
220 	omap_common_suspend_init(omap2_enter_full_retention);
221 
222 	/* REVISIT: Configure number of 32 kHz clock cycles for sys_clk
223 	 * stabilisation */
224 	omap2_prm_write_mod_reg(15 << OMAP_SETUP_TIME_SHIFT, OMAP24XX_GR_MOD,
225 				OMAP2_PRCM_CLKSSETUP_OFFSET);
226 
227 	/* Configure automatic voltage transition */
228 	omap2_prm_write_mod_reg(2 << OMAP_SETUP_TIME_SHIFT, OMAP24XX_GR_MOD,
229 				OMAP2_PRCM_VOLTSETUP_OFFSET);
230 	omap2_prm_write_mod_reg(OMAP24XX_AUTO_EXTVOLT_MASK |
231 				(0x1 << OMAP24XX_SETOFF_LEVEL_SHIFT) |
232 				OMAP24XX_MEMRETCTRL_MASK |
233 				(0x1 << OMAP24XX_SETRET_LEVEL_SHIFT) |
234 				(0x0 << OMAP24XX_VOLT_LEVEL_SHIFT),
235 				OMAP24XX_GR_MOD, OMAP2_PRCM_VOLTCTRL_OFFSET);
236 
237 	/* Enable wake-up events */
238 	omap2_prm_write_mod_reg(OMAP24XX_EN_GPIOS_MASK | OMAP24XX_EN_GPT1_MASK,
239 				WKUP_MOD, PM_WKEN);
240 
241 	/* Enable SYS_CLKEN control when all domains idle */
242 	omap2_prm_set_mod_reg_bits(OMAP_AUTOEXTCLKMODE_MASK, OMAP24XX_GR_MOD,
243 				   OMAP2_PRCM_CLKSRC_CTRL_OFFSET);
244 }
245 
omap2_pm_init(void)246 int __init omap2_pm_init(void)
247 {
248 	u32 l;
249 
250 	printk(KERN_INFO "Power Management for OMAP2 initializing\n");
251 	l = omap2_prm_read_mod_reg(OCP_MOD, OMAP2_PRCM_REVISION_OFFSET);
252 	printk(KERN_INFO "PRCM revision %d.%d\n", (l >> 4) & 0x0f, l & 0x0f);
253 
254 	/* Look up important powerdomains */
255 
256 	mpu_pwrdm = pwrdm_lookup("mpu_pwrdm");
257 	if (!mpu_pwrdm)
258 		pr_err("PM: mpu_pwrdm not found\n");
259 
260 	core_pwrdm = pwrdm_lookup("core_pwrdm");
261 	if (!core_pwrdm)
262 		pr_err("PM: core_pwrdm not found\n");
263 
264 	/* Look up important clockdomains */
265 
266 	mpu_clkdm = clkdm_lookup("mpu_clkdm");
267 	if (!mpu_clkdm)
268 		pr_err("PM: mpu_clkdm not found\n");
269 
270 	wkup_clkdm = clkdm_lookup("wkup_clkdm");
271 	if (!wkup_clkdm)
272 		pr_err("PM: wkup_clkdm not found\n");
273 
274 	dsp_clkdm = clkdm_lookup("dsp_clkdm");
275 	if (!dsp_clkdm)
276 		pr_err("PM: dsp_clkdm not found\n");
277 
278 	gfx_clkdm = clkdm_lookup("gfx_clkdm");
279 	if (!gfx_clkdm)
280 		pr_err("PM: gfx_clkdm not found\n");
281 
282 
283 	osc_ck = clk_get(NULL, "osc_ck");
284 	if (IS_ERR(osc_ck)) {
285 		printk(KERN_ERR "could not get osc_ck\n");
286 		return -ENODEV;
287 	}
288 
289 	if (cpu_is_omap242x()) {
290 		emul_ck = clk_get(NULL, "emul_ck");
291 		if (IS_ERR(emul_ck)) {
292 			printk(KERN_ERR "could not get emul_ck\n");
293 			clk_put(osc_ck);
294 			return -ENODEV;
295 		}
296 	}
297 
298 	prcm_setup_regs();
299 
300 	/*
301 	 * We copy the assembler sleep/wakeup routines to SRAM.
302 	 * These routines need to be in SRAM as that's the only
303 	 * memory the MPU can see when it wakes up after the entire
304 	 * chip enters idle.
305 	 */
306 	omap2_sram_suspend = omap_sram_push(omap24xx_cpu_suspend,
307 					    omap24xx_cpu_suspend_sz);
308 
309 	arm_pm_idle = omap2_pm_idle;
310 
311 	return 0;
312 }
313