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v3.5.6
  1/*
  2 * OMAP MPUSS low power code
  3 *
  4 * Copyright (C) 2011 Texas Instruments, Inc.
  5 *	Santosh Shilimkar <santosh.shilimkar@ti.com>
  6 *
  7 * OMAP4430 MPUSS mainly consists of dual Cortex-A9 with per-CPU
  8 * Local timer and Watchdog, GIC, SCU, PL310 L2 cache controller,
  9 * CPU0 and CPU1 LPRM modules.
 10 * CPU0, CPU1 and MPUSS each have there own power domain and
 11 * hence multiple low power combinations of MPUSS are possible.
 12 *
 13 * The CPU0 and CPU1 can't support Closed switch Retention (CSWR)
 14 * because the mode is not supported by hw constraints of dormant
 15 * mode. While waking up from the dormant mode, a reset  signal
 16 * to the Cortex-A9 processor must be asserted by the external
 17 * power controller.
 18 *
 19 * With architectural inputs and hardware recommendations, only
 20 * below modes are supported from power gain vs latency point of view.
 21 *
 22 *	CPU0		CPU1		MPUSS
 23 *	----------------------------------------------
 24 *	ON		ON		ON
 25 *	ON(Inactive)	OFF		ON(Inactive)
 26 *	OFF		OFF		CSWR
 27 *	OFF		OFF		OSWR
 28 *	OFF		OFF		OFF(Device OFF *TBD)
 29 *	----------------------------------------------
 30 *
 31 * Note: CPU0 is the master core and it is the last CPU to go down
 32 * and first to wake-up when MPUSS low power states are excercised
 33 *
 34 *
 35 * This program is free software; you can redistribute it and/or modify
 36 * it under the terms of the GNU General Public License version 2 as
 37 * published by the Free Software Foundation.
 38 */
 39
 40#include <linux/kernel.h>
 41#include <linux/io.h>
 42#include <linux/errno.h>
 43#include <linux/linkage.h>
 44#include <linux/smp.h>
 45
 46#include <asm/cacheflush.h>
 47#include <asm/tlbflush.h>
 48#include <asm/smp_scu.h>
 49#include <asm/pgalloc.h>
 50#include <asm/suspend.h>
 51#include <asm/hardware/cache-l2x0.h>
 52
 53#include <plat/omap44xx.h>
 54
 55#include "common.h"
 
 56#include "omap4-sar-layout.h"
 57#include "pm.h"
 58#include "prcm_mpu44xx.h"
 59#include "prminst44xx.h"
 60#include "prcm44xx.h"
 61#include "prm44xx.h"
 62#include "prm-regbits-44xx.h"
 63
 64#ifdef CONFIG_SMP
 65
 66struct omap4_cpu_pm_info {
 67	struct powerdomain *pwrdm;
 68	void __iomem *scu_sar_addr;
 69	void __iomem *wkup_sar_addr;
 70	void __iomem *l2x0_sar_addr;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 71};
 72
 73static DEFINE_PER_CPU(struct omap4_cpu_pm_info, omap4_pm_info);
 74static struct powerdomain *mpuss_pd;
 75static void __iomem *sar_base;
 76
 77/*
 78 * Program the wakeup routine address for the CPU0 and CPU1
 79 * used for OFF or DORMANT wakeup.
 80 */
 81static inline void set_cpu_wakeup_addr(unsigned int cpu_id, u32 addr)
 82{
 83	struct omap4_cpu_pm_info *pm_info = &per_cpu(omap4_pm_info, cpu_id);
 84
 85	__raw_writel(addr, pm_info->wkup_sar_addr);
 86}
 87
 88/*
 89 * Set the CPUx powerdomain's previous power state
 90 */
 91static inline void set_cpu_next_pwrst(unsigned int cpu_id,
 92				unsigned int power_state)
 93{
 94	struct omap4_cpu_pm_info *pm_info = &per_cpu(omap4_pm_info, cpu_id);
 95
 96	pwrdm_set_next_pwrst(pm_info->pwrdm, power_state);
 97}
 98
 99/*
100 * Read CPU's previous power state
101 */
102static inline unsigned int read_cpu_prev_pwrst(unsigned int cpu_id)
103{
104	struct omap4_cpu_pm_info *pm_info = &per_cpu(omap4_pm_info, cpu_id);
105
106	return pwrdm_read_prev_pwrst(pm_info->pwrdm);
107}
 
 
 
108
109/*
110 * Clear the CPUx powerdomain's previous power state
 
111 */
112static inline void clear_cpu_prev_pwrst(unsigned int cpu_id)
113{
114	struct omap4_cpu_pm_info *pm_info = &per_cpu(omap4_pm_info, cpu_id);
115
116	pwrdm_clear_all_prev_pwrst(pm_info->pwrdm);
117}
118
119/*
120 * Store the SCU power status value to scratchpad memory
121 */
122static void scu_pwrst_prepare(unsigned int cpu_id, unsigned int cpu_state)
123{
124	struct omap4_cpu_pm_info *pm_info = &per_cpu(omap4_pm_info, cpu_id);
125	u32 scu_pwr_st;
126
127	switch (cpu_state) {
128	case PWRDM_POWER_RET:
129		scu_pwr_st = SCU_PM_DORMANT;
130		break;
131	case PWRDM_POWER_OFF:
132		scu_pwr_st = SCU_PM_POWEROFF;
133		break;
134	case PWRDM_POWER_ON:
135	case PWRDM_POWER_INACTIVE:
136	default:
137		scu_pwr_st = SCU_PM_NORMAL;
138		break;
139	}
140
141	__raw_writel(scu_pwr_st, pm_info->scu_sar_addr);
142}
143
144/* Helper functions for MPUSS OSWR */
145static inline void mpuss_clear_prev_logic_pwrst(void)
146{
147	u32 reg;
148
149	reg = omap4_prminst_read_inst_reg(OMAP4430_PRM_PARTITION,
150		OMAP4430_PRM_MPU_INST, OMAP4_RM_MPU_MPU_CONTEXT_OFFSET);
151	omap4_prminst_write_inst_reg(reg, OMAP4430_PRM_PARTITION,
152		OMAP4430_PRM_MPU_INST, OMAP4_RM_MPU_MPU_CONTEXT_OFFSET);
153}
154
155static inline void cpu_clear_prev_logic_pwrst(unsigned int cpu_id)
156{
157	u32 reg;
158
159	if (cpu_id) {
160		reg = omap4_prcm_mpu_read_inst_reg(OMAP4430_PRCM_MPU_CPU1_INST,
161					OMAP4_RM_CPU1_CPU1_CONTEXT_OFFSET);
162		omap4_prcm_mpu_write_inst_reg(reg, OMAP4430_PRCM_MPU_CPU1_INST,
163					OMAP4_RM_CPU1_CPU1_CONTEXT_OFFSET);
164	} else {
165		reg = omap4_prcm_mpu_read_inst_reg(OMAP4430_PRCM_MPU_CPU0_INST,
166					OMAP4_RM_CPU0_CPU0_CONTEXT_OFFSET);
167		omap4_prcm_mpu_write_inst_reg(reg, OMAP4430_PRCM_MPU_CPU0_INST,
168					OMAP4_RM_CPU0_CPU0_CONTEXT_OFFSET);
169	}
170}
171
172/**
173 * omap4_mpuss_read_prev_context_state:
174 * Function returns the MPUSS previous context state
175 */
176u32 omap4_mpuss_read_prev_context_state(void)
177{
178	u32 reg;
179
180	reg = omap4_prminst_read_inst_reg(OMAP4430_PRM_PARTITION,
181		OMAP4430_PRM_MPU_INST, OMAP4_RM_MPU_MPU_CONTEXT_OFFSET);
182	reg &= OMAP4430_LOSTCONTEXT_DFF_MASK;
183	return reg;
184}
185
186/*
187 * Store the CPU cluster state for L2X0 low power operations.
188 */
189static void l2x0_pwrst_prepare(unsigned int cpu_id, unsigned int save_state)
190{
191	struct omap4_cpu_pm_info *pm_info = &per_cpu(omap4_pm_info, cpu_id);
192
193	__raw_writel(save_state, pm_info->l2x0_sar_addr);
194}
195
196/*
197 * Save the L2X0 AUXCTRL and POR value to SAR memory. Its used to
198 * in every restore MPUSS OFF path.
199 */
200#ifdef CONFIG_CACHE_L2X0
201static void save_l2x0_context(void)
202{
203	u32 val;
204	void __iomem *l2x0_base = omap4_get_l2cache_base();
205
206	val = __raw_readl(l2x0_base + L2X0_AUX_CTRL);
207	__raw_writel(val, sar_base + L2X0_AUXCTRL_OFFSET);
208	val = __raw_readl(l2x0_base + L2X0_PREFETCH_CTRL);
209	__raw_writel(val, sar_base + L2X0_PREFETCH_CTRL_OFFSET);
 
210}
211#else
212static void save_l2x0_context(void)
213{}
214#endif
215
216/**
217 * omap4_enter_lowpower: OMAP4 MPUSS Low Power Entry Function
218 * The purpose of this function is to manage low power programming
219 * of OMAP4 MPUSS subsystem
220 * @cpu : CPU ID
221 * @power_state: Low power state.
222 *
223 * MPUSS states for the context save:
224 * save_state =
225 *	0 - Nothing lost and no need to save: MPUSS INACTIVE
226 *	1 - CPUx L1 and logic lost: MPUSS CSWR
227 *	2 - CPUx L1 and logic lost + GIC lost: MPUSS OSWR
228 *	3 - CPUx L1 and logic lost + GIC + L2 lost: DEVICE OFF
229 */
230int omap4_enter_lowpower(unsigned int cpu, unsigned int power_state)
231{
 
232	unsigned int save_state = 0;
233	unsigned int wakeup_cpu;
234
235	if (omap_rev() == OMAP4430_REV_ES1_0)
236		return -ENXIO;
237
238	switch (power_state) {
239	case PWRDM_POWER_ON:
240	case PWRDM_POWER_INACTIVE:
241		save_state = 0;
242		break;
243	case PWRDM_POWER_OFF:
244		save_state = 1;
245		break;
246	case PWRDM_POWER_RET:
247	default:
248		/*
249		 * CPUx CSWR is invalid hardware state. Also CPUx OSWR
250		 * doesn't make much scense, since logic is lost and $L1
251		 * needs to be cleaned because of coherency. This makes
252		 * CPUx OSWR equivalent to CPUX OFF and hence not supported
253		 */
254		WARN_ON(1);
255		return -ENXIO;
256	}
257
258	pwrdm_pre_transition();
259
260	/*
261	 * Check MPUSS next state and save interrupt controller if needed.
262	 * In MPUSS OSWR or device OFF, interrupt controller  contest is lost.
263	 */
264	mpuss_clear_prev_logic_pwrst();
265	if ((pwrdm_read_next_pwrst(mpuss_pd) == PWRDM_POWER_RET) &&
266		(pwrdm_read_logic_retst(mpuss_pd) == PWRDM_POWER_OFF))
267		save_state = 2;
268
269	cpu_clear_prev_logic_pwrst(cpu);
270	set_cpu_next_pwrst(cpu, power_state);
271	set_cpu_wakeup_addr(cpu, virt_to_phys(omap4_cpu_resume));
272	scu_pwrst_prepare(cpu, power_state);
273	l2x0_pwrst_prepare(cpu, save_state);
274
275	/*
276	 * Call low level function  with targeted low power state.
277	 */
278	cpu_suspend(save_state, omap4_finish_suspend);
 
 
 
 
 
 
279
280	/*
281	 * Restore the CPUx power state to ON otherwise CPUx
282	 * power domain can transitions to programmed low power
283	 * state while doing WFI outside the low powe code. On
284	 * secure devices, CPUx does WFI which can result in
285	 * domain transition
286	 */
287	wakeup_cpu = smp_processor_id();
288	set_cpu_next_pwrst(wakeup_cpu, PWRDM_POWER_ON);
289
290	pwrdm_post_transition();
291
292	return 0;
293}
294
295/**
296 * omap4_hotplug_cpu: OMAP4 CPU hotplug entry
297 * @cpu : CPU ID
298 * @power_state: CPU low power state.
299 */
300int __cpuinit omap4_hotplug_cpu(unsigned int cpu, unsigned int power_state)
301{
 
302	unsigned int cpu_state = 0;
303
304	if (omap_rev() == OMAP4430_REV_ES1_0)
305		return -ENXIO;
306
307	if (power_state == PWRDM_POWER_OFF)
308		cpu_state = 1;
309
310	clear_cpu_prev_pwrst(cpu);
311	set_cpu_next_pwrst(cpu, power_state);
312	set_cpu_wakeup_addr(cpu, virt_to_phys(omap_secondary_startup));
313	scu_pwrst_prepare(cpu, power_state);
314
315	/*
316	 * CPU never retuns back if targetted power state is OFF mode.
317	 * CPU ONLINE follows normal CPU ONLINE ptah via
318	 * omap_secondary_startup().
319	 */
320	omap4_finish_suspend(cpu_state);
321
322	set_cpu_next_pwrst(cpu, PWRDM_POWER_ON);
323	return 0;
324}
325
326
327/*
328 * Initialise OMAP4 MPUSS
329 */
330int __init omap4_mpuss_init(void)
331{
332	struct omap4_cpu_pm_info *pm_info;
333
334	if (omap_rev() == OMAP4430_REV_ES1_0) {
335		WARN(1, "Power Management not supported on OMAP4430 ES1.0\n");
336		return -ENODEV;
337	}
338
339	sar_base = omap4_get_sar_ram_base();
340
341	/* Initilaise per CPU PM information */
342	pm_info = &per_cpu(omap4_pm_info, 0x0);
343	pm_info->scu_sar_addr = sar_base + SCU_OFFSET0;
344	pm_info->wkup_sar_addr = sar_base + CPU0_WAKEUP_NS_PA_ADDR_OFFSET;
345	pm_info->l2x0_sar_addr = sar_base + L2X0_SAVE_OFFSET0;
346	pm_info->pwrdm = pwrdm_lookup("cpu0_pwrdm");
347	if (!pm_info->pwrdm) {
348		pr_err("Lookup failed for CPU0 pwrdm\n");
349		return -ENODEV;
350	}
351
352	/* Clear CPU previous power domain state */
353	pwrdm_clear_all_prev_pwrst(pm_info->pwrdm);
354	cpu_clear_prev_logic_pwrst(0);
355
356	/* Initialise CPU0 power domain state to ON */
357	pwrdm_set_next_pwrst(pm_info->pwrdm, PWRDM_POWER_ON);
358
359	pm_info = &per_cpu(omap4_pm_info, 0x1);
360	pm_info->scu_sar_addr = sar_base + SCU_OFFSET1;
361	pm_info->wkup_sar_addr = sar_base + CPU1_WAKEUP_NS_PA_ADDR_OFFSET;
362	pm_info->l2x0_sar_addr = sar_base + L2X0_SAVE_OFFSET1;
 
 
 
 
 
363	pm_info->pwrdm = pwrdm_lookup("cpu1_pwrdm");
364	if (!pm_info->pwrdm) {
365		pr_err("Lookup failed for CPU1 pwrdm\n");
366		return -ENODEV;
367	}
368
369	/* Clear CPU previous power domain state */
370	pwrdm_clear_all_prev_pwrst(pm_info->pwrdm);
371	cpu_clear_prev_logic_pwrst(1);
372
373	/* Initialise CPU1 power domain state to ON */
374	pwrdm_set_next_pwrst(pm_info->pwrdm, PWRDM_POWER_ON);
375
376	mpuss_pd = pwrdm_lookup("mpu_pwrdm");
377	if (!mpuss_pd) {
378		pr_err("Failed to lookup MPUSS power domain\n");
379		return -ENODEV;
380	}
381	pwrdm_clear_all_prev_pwrst(mpuss_pd);
382	mpuss_clear_prev_logic_pwrst();
383
384	/* Save device type on scratchpad for low level code to use */
385	if (omap_type() != OMAP2_DEVICE_TYPE_GP)
386		__raw_writel(1, sar_base + OMAP_TYPE_OFFSET);
387	else
388		__raw_writel(0, sar_base + OMAP_TYPE_OFFSET);
389
390	save_l2x0_context();
 
 
 
 
 
 
391
392	return 0;
393}
394
395#endif
v3.15
  1/*
  2 * OMAP MPUSS low power code
  3 *
  4 * Copyright (C) 2011 Texas Instruments, Inc.
  5 *	Santosh Shilimkar <santosh.shilimkar@ti.com>
  6 *
  7 * OMAP4430 MPUSS mainly consists of dual Cortex-A9 with per-CPU
  8 * Local timer and Watchdog, GIC, SCU, PL310 L2 cache controller,
  9 * CPU0 and CPU1 LPRM modules.
 10 * CPU0, CPU1 and MPUSS each have there own power domain and
 11 * hence multiple low power combinations of MPUSS are possible.
 12 *
 13 * The CPU0 and CPU1 can't support Closed switch Retention (CSWR)
 14 * because the mode is not supported by hw constraints of dormant
 15 * mode. While waking up from the dormant mode, a reset  signal
 16 * to the Cortex-A9 processor must be asserted by the external
 17 * power controller.
 18 *
 19 * With architectural inputs and hardware recommendations, only
 20 * below modes are supported from power gain vs latency point of view.
 21 *
 22 *	CPU0		CPU1		MPUSS
 23 *	----------------------------------------------
 24 *	ON		ON		ON
 25 *	ON(Inactive)	OFF		ON(Inactive)
 26 *	OFF		OFF		CSWR
 27 *	OFF		OFF		OSWR
 28 *	OFF		OFF		OFF(Device OFF *TBD)
 29 *	----------------------------------------------
 30 *
 31 * Note: CPU0 is the master core and it is the last CPU to go down
 32 * and first to wake-up when MPUSS low power states are excercised
 33 *
 34 *
 35 * This program is free software; you can redistribute it and/or modify
 36 * it under the terms of the GNU General Public License version 2 as
 37 * published by the Free Software Foundation.
 38 */
 39
 40#include <linux/kernel.h>
 41#include <linux/io.h>
 42#include <linux/errno.h>
 43#include <linux/linkage.h>
 44#include <linux/smp.h>
 45
 46#include <asm/cacheflush.h>
 47#include <asm/tlbflush.h>
 48#include <asm/smp_scu.h>
 49#include <asm/pgalloc.h>
 50#include <asm/suspend.h>
 51#include <asm/hardware/cache-l2x0.h>
 52
 53#include "soc.h"
 
 54#include "common.h"
 55#include "omap44xx.h"
 56#include "omap4-sar-layout.h"
 57#include "pm.h"
 58#include "prcm_mpu44xx.h"
 59#include "prminst44xx.h"
 60#include "prcm44xx.h"
 61#include "prm44xx.h"
 62#include "prm-regbits-44xx.h"
 63
 64#ifdef CONFIG_SMP
 65
 66struct omap4_cpu_pm_info {
 67	struct powerdomain *pwrdm;
 68	void __iomem *scu_sar_addr;
 69	void __iomem *wkup_sar_addr;
 70	void __iomem *l2x0_sar_addr;
 71	void (*secondary_startup)(void);
 72};
 73
 74/**
 75 * struct cpu_pm_ops - CPU pm operations
 76 * @finish_suspend:	CPU suspend finisher function pointer
 77 * @resume:		CPU resume function pointer
 78 * @scu_prepare:	CPU Snoop Control program function pointer
 79 *
 80 * Structure holds functions pointer for CPU low power operations like
 81 * suspend, resume and scu programming.
 82 */
 83struct cpu_pm_ops {
 84	int (*finish_suspend)(unsigned long cpu_state);
 85	void (*resume)(void);
 86	void (*scu_prepare)(unsigned int cpu_id, unsigned int cpu_state);
 87};
 88
 89static DEFINE_PER_CPU(struct omap4_cpu_pm_info, omap4_pm_info);
 90static struct powerdomain *mpuss_pd;
 91static void __iomem *sar_base;
 92
 93static int default_finish_suspend(unsigned long cpu_state)
 
 
 
 
 94{
 95	omap_do_wfi();
 96	return 0;
 
 97}
 98
 99static void dummy_cpu_resume(void)
100{}
 
 
 
 
 
 
 
 
101
102static void dummy_scu_prepare(unsigned int cpu_id, unsigned int cpu_state)
103{}
 
 
 
 
104
105struct cpu_pm_ops omap_pm_ops = {
106	.finish_suspend		= default_finish_suspend,
107	.resume			= dummy_cpu_resume,
108	.scu_prepare		= dummy_scu_prepare,
109};
110
111/*
112 * Program the wakeup routine address for the CPU0 and CPU1
113 * used for OFF or DORMANT wakeup.
114 */
115static inline void set_cpu_wakeup_addr(unsigned int cpu_id, u32 addr)
116{
117	struct omap4_cpu_pm_info *pm_info = &per_cpu(omap4_pm_info, cpu_id);
118
119	__raw_writel(addr, pm_info->wkup_sar_addr);
120}
121
122/*
123 * Store the SCU power status value to scratchpad memory
124 */
125static void scu_pwrst_prepare(unsigned int cpu_id, unsigned int cpu_state)
126{
127	struct omap4_cpu_pm_info *pm_info = &per_cpu(omap4_pm_info, cpu_id);
128	u32 scu_pwr_st;
129
130	switch (cpu_state) {
131	case PWRDM_POWER_RET:
132		scu_pwr_st = SCU_PM_DORMANT;
133		break;
134	case PWRDM_POWER_OFF:
135		scu_pwr_st = SCU_PM_POWEROFF;
136		break;
137	case PWRDM_POWER_ON:
138	case PWRDM_POWER_INACTIVE:
139	default:
140		scu_pwr_st = SCU_PM_NORMAL;
141		break;
142	}
143
144	__raw_writel(scu_pwr_st, pm_info->scu_sar_addr);
145}
146
147/* Helper functions for MPUSS OSWR */
148static inline void mpuss_clear_prev_logic_pwrst(void)
149{
150	u32 reg;
151
152	reg = omap4_prminst_read_inst_reg(OMAP4430_PRM_PARTITION,
153		OMAP4430_PRM_MPU_INST, OMAP4_RM_MPU_MPU_CONTEXT_OFFSET);
154	omap4_prminst_write_inst_reg(reg, OMAP4430_PRM_PARTITION,
155		OMAP4430_PRM_MPU_INST, OMAP4_RM_MPU_MPU_CONTEXT_OFFSET);
156}
157
158static inline void cpu_clear_prev_logic_pwrst(unsigned int cpu_id)
159{
160	u32 reg;
161
162	if (cpu_id) {
163		reg = omap4_prcm_mpu_read_inst_reg(OMAP4430_PRCM_MPU_CPU1_INST,
164					OMAP4_RM_CPU1_CPU1_CONTEXT_OFFSET);
165		omap4_prcm_mpu_write_inst_reg(reg, OMAP4430_PRCM_MPU_CPU1_INST,
166					OMAP4_RM_CPU1_CPU1_CONTEXT_OFFSET);
167	} else {
168		reg = omap4_prcm_mpu_read_inst_reg(OMAP4430_PRCM_MPU_CPU0_INST,
169					OMAP4_RM_CPU0_CPU0_CONTEXT_OFFSET);
170		omap4_prcm_mpu_write_inst_reg(reg, OMAP4430_PRCM_MPU_CPU0_INST,
171					OMAP4_RM_CPU0_CPU0_CONTEXT_OFFSET);
172	}
173}
174
 
 
 
 
 
 
 
 
 
 
 
 
 
 
175/*
176 * Store the CPU cluster state for L2X0 low power operations.
177 */
178static void l2x0_pwrst_prepare(unsigned int cpu_id, unsigned int save_state)
179{
180	struct omap4_cpu_pm_info *pm_info = &per_cpu(omap4_pm_info, cpu_id);
181
182	__raw_writel(save_state, pm_info->l2x0_sar_addr);
183}
184
185/*
186 * Save the L2X0 AUXCTRL and POR value to SAR memory. Its used to
187 * in every restore MPUSS OFF path.
188 */
189#ifdef CONFIG_CACHE_L2X0
190static void save_l2x0_context(void)
191{
192	u32 val;
193	void __iomem *l2x0_base = omap4_get_l2cache_base();
194	if (l2x0_base) {
195		val = __raw_readl(l2x0_base + L2X0_AUX_CTRL);
196		__raw_writel(val, sar_base + L2X0_AUXCTRL_OFFSET);
197		val = __raw_readl(l2x0_base + L2X0_PREFETCH_CTRL);
198		__raw_writel(val, sar_base + L2X0_PREFETCH_CTRL_OFFSET);
199	}
200}
201#else
202static void save_l2x0_context(void)
203{}
204#endif
205
206/**
207 * omap4_enter_lowpower: OMAP4 MPUSS Low Power Entry Function
208 * The purpose of this function is to manage low power programming
209 * of OMAP4 MPUSS subsystem
210 * @cpu : CPU ID
211 * @power_state: Low power state.
212 *
213 * MPUSS states for the context save:
214 * save_state =
215 *	0 - Nothing lost and no need to save: MPUSS INACTIVE
216 *	1 - CPUx L1 and logic lost: MPUSS CSWR
217 *	2 - CPUx L1 and logic lost + GIC lost: MPUSS OSWR
218 *	3 - CPUx L1 and logic lost + GIC + L2 lost: DEVICE OFF
219 */
220int omap4_enter_lowpower(unsigned int cpu, unsigned int power_state)
221{
222	struct omap4_cpu_pm_info *pm_info = &per_cpu(omap4_pm_info, cpu);
223	unsigned int save_state = 0;
224	unsigned int wakeup_cpu;
225
226	if (omap_rev() == OMAP4430_REV_ES1_0)
227		return -ENXIO;
228
229	switch (power_state) {
230	case PWRDM_POWER_ON:
231	case PWRDM_POWER_INACTIVE:
232		save_state = 0;
233		break;
234	case PWRDM_POWER_OFF:
235		save_state = 1;
236		break;
237	case PWRDM_POWER_RET:
238	default:
239		/*
240		 * CPUx CSWR is invalid hardware state. Also CPUx OSWR
241		 * doesn't make much scense, since logic is lost and $L1
242		 * needs to be cleaned because of coherency. This makes
243		 * CPUx OSWR equivalent to CPUX OFF and hence not supported
244		 */
245		WARN_ON(1);
246		return -ENXIO;
247	}
248
249	pwrdm_pre_transition(NULL);
250
251	/*
252	 * Check MPUSS next state and save interrupt controller if needed.
253	 * In MPUSS OSWR or device OFF, interrupt controller  contest is lost.
254	 */
255	mpuss_clear_prev_logic_pwrst();
256	if ((pwrdm_read_next_pwrst(mpuss_pd) == PWRDM_POWER_RET) &&
257		(pwrdm_read_logic_retst(mpuss_pd) == PWRDM_POWER_OFF))
258		save_state = 2;
259
260	cpu_clear_prev_logic_pwrst(cpu);
261	pwrdm_set_next_pwrst(pm_info->pwrdm, power_state);
262	set_cpu_wakeup_addr(cpu, virt_to_phys(omap_pm_ops.resume));
263	omap_pm_ops.scu_prepare(cpu, power_state);
264	l2x0_pwrst_prepare(cpu, save_state);
265
266	/*
267	 * Call low level function  with targeted low power state.
268	 */
269	if (save_state)
270		cpu_suspend(save_state, omap_pm_ops.finish_suspend);
271	else
272		omap_pm_ops.finish_suspend(save_state);
273
274	if (IS_PM44XX_ERRATUM(PM_OMAP4_ROM_SMP_BOOT_ERRATUM_GICD) && cpu)
275		gic_dist_enable();
276
277	/*
278	 * Restore the CPUx power state to ON otherwise CPUx
279	 * power domain can transitions to programmed low power
280	 * state while doing WFI outside the low powe code. On
281	 * secure devices, CPUx does WFI which can result in
282	 * domain transition
283	 */
284	wakeup_cpu = smp_processor_id();
285	pwrdm_set_next_pwrst(pm_info->pwrdm, PWRDM_POWER_ON);
286
287	pwrdm_post_transition(NULL);
288
289	return 0;
290}
291
292/**
293 * omap4_hotplug_cpu: OMAP4 CPU hotplug entry
294 * @cpu : CPU ID
295 * @power_state: CPU low power state.
296 */
297int omap4_hotplug_cpu(unsigned int cpu, unsigned int power_state)
298{
299	struct omap4_cpu_pm_info *pm_info = &per_cpu(omap4_pm_info, cpu);
300	unsigned int cpu_state = 0;
301
302	if (omap_rev() == OMAP4430_REV_ES1_0)
303		return -ENXIO;
304
305	if (power_state == PWRDM_POWER_OFF)
306		cpu_state = 1;
307
308	pwrdm_clear_all_prev_pwrst(pm_info->pwrdm);
309	pwrdm_set_next_pwrst(pm_info->pwrdm, power_state);
310	set_cpu_wakeup_addr(cpu, virt_to_phys(pm_info->secondary_startup));
311	omap_pm_ops.scu_prepare(cpu, power_state);
312
313	/*
314	 * CPU never retuns back if targeted power state is OFF mode.
315	 * CPU ONLINE follows normal CPU ONLINE ptah via
316	 * omap4_secondary_startup().
317	 */
318	omap_pm_ops.finish_suspend(cpu_state);
319
320	pwrdm_set_next_pwrst(pm_info->pwrdm, PWRDM_POWER_ON);
321	return 0;
322}
323
324
325/*
326 * Initialise OMAP4 MPUSS
327 */
328int __init omap4_mpuss_init(void)
329{
330	struct omap4_cpu_pm_info *pm_info;
331
332	if (omap_rev() == OMAP4430_REV_ES1_0) {
333		WARN(1, "Power Management not supported on OMAP4430 ES1.0\n");
334		return -ENODEV;
335	}
336
337	sar_base = omap4_get_sar_ram_base();
338
339	/* Initilaise per CPU PM information */
340	pm_info = &per_cpu(omap4_pm_info, 0x0);
341	pm_info->scu_sar_addr = sar_base + SCU_OFFSET0;
342	pm_info->wkup_sar_addr = sar_base + CPU0_WAKEUP_NS_PA_ADDR_OFFSET;
343	pm_info->l2x0_sar_addr = sar_base + L2X0_SAVE_OFFSET0;
344	pm_info->pwrdm = pwrdm_lookup("cpu0_pwrdm");
345	if (!pm_info->pwrdm) {
346		pr_err("Lookup failed for CPU0 pwrdm\n");
347		return -ENODEV;
348	}
349
350	/* Clear CPU previous power domain state */
351	pwrdm_clear_all_prev_pwrst(pm_info->pwrdm);
352	cpu_clear_prev_logic_pwrst(0);
353
354	/* Initialise CPU0 power domain state to ON */
355	pwrdm_set_next_pwrst(pm_info->pwrdm, PWRDM_POWER_ON);
356
357	pm_info = &per_cpu(omap4_pm_info, 0x1);
358	pm_info->scu_sar_addr = sar_base + SCU_OFFSET1;
359	pm_info->wkup_sar_addr = sar_base + CPU1_WAKEUP_NS_PA_ADDR_OFFSET;
360	pm_info->l2x0_sar_addr = sar_base + L2X0_SAVE_OFFSET1;
361	if (cpu_is_omap446x())
362		pm_info->secondary_startup = omap4460_secondary_startup;
363	else
364		pm_info->secondary_startup = omap4_secondary_startup;
365
366	pm_info->pwrdm = pwrdm_lookup("cpu1_pwrdm");
367	if (!pm_info->pwrdm) {
368		pr_err("Lookup failed for CPU1 pwrdm\n");
369		return -ENODEV;
370	}
371
372	/* Clear CPU previous power domain state */
373	pwrdm_clear_all_prev_pwrst(pm_info->pwrdm);
374	cpu_clear_prev_logic_pwrst(1);
375
376	/* Initialise CPU1 power domain state to ON */
377	pwrdm_set_next_pwrst(pm_info->pwrdm, PWRDM_POWER_ON);
378
379	mpuss_pd = pwrdm_lookup("mpu_pwrdm");
380	if (!mpuss_pd) {
381		pr_err("Failed to lookup MPUSS power domain\n");
382		return -ENODEV;
383	}
384	pwrdm_clear_all_prev_pwrst(mpuss_pd);
385	mpuss_clear_prev_logic_pwrst();
386
387	/* Save device type on scratchpad for low level code to use */
388	if (omap_type() != OMAP2_DEVICE_TYPE_GP)
389		__raw_writel(1, sar_base + OMAP_TYPE_OFFSET);
390	else
391		__raw_writel(0, sar_base + OMAP_TYPE_OFFSET);
392
393	save_l2x0_context();
394
395	if (cpu_is_omap44xx()) {
396		omap_pm_ops.finish_suspend = omap4_finish_suspend;
397		omap_pm_ops.resume = omap4_cpu_resume;
398		omap_pm_ops.scu_prepare = scu_pwrst_prepare;
399	}
400
401	return 0;
402}
403
404#endif