2 * OMAP MPUSS low power code
4 * Copyright (C) 2011 Texas Instruments, Inc.
5 * Santosh Shilimkar <santosh.shilimkar@ti.com>
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.
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
19 * With architectural inputs and hardware recommendations, only
20 * below modes are supported from power gain vs latency point of view.
23 * ----------------------------------------------
25 * ON(Inactive) OFF ON(Inactive)
28 * OFF OFF OFF(Device OFF *TBD)
29 * ----------------------------------------------
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
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.
40 #include <linux/kernel.h>
42 #include <linux/errno.h>
43 #include <linux/linkage.h>
44 #include <linux/smp.h>
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>
56 #include "omap4-sar-layout.h"
58 #include "prcm_mpu44xx.h"
59 #include "prminst44xx.h"
62 #include "prm-regbits-44xx.h"
66 struct 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);
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
80 * Structure holds functions pointer for CPU low power operations like
81 * suspend, resume and scu programming.
84 int (*finish_suspend)(unsigned long cpu_state);
86 void (*scu_prepare)(unsigned int cpu_id, unsigned int cpu_state);
89 static DEFINE_PER_CPU(struct omap4_cpu_pm_info, omap4_pm_info);
90 static struct powerdomain *mpuss_pd;
91 static void __iomem *sar_base;
93 static int default_finish_suspend(unsigned long cpu_state)
99 static void dummy_cpu_resume(void)
102 static void dummy_scu_prepare(unsigned int cpu_id, unsigned int cpu_state)
105 struct cpu_pm_ops omap_pm_ops = {
106 .finish_suspend = default_finish_suspend,
107 .resume = dummy_cpu_resume,
108 .scu_prepare = dummy_scu_prepare,
112 * Program the wakeup routine address for the CPU0 and CPU1
113 * used for OFF or DORMANT wakeup.
115 static inline void set_cpu_wakeup_addr(unsigned int cpu_id, u32 addr)
117 struct omap4_cpu_pm_info *pm_info = &per_cpu(omap4_pm_info, cpu_id);
119 __raw_writel(addr, pm_info->wkup_sar_addr);
123 * Store the SCU power status value to scratchpad memory
125 static void scu_pwrst_prepare(unsigned int cpu_id, unsigned int cpu_state)
127 struct omap4_cpu_pm_info *pm_info = &per_cpu(omap4_pm_info, cpu_id);
131 case PWRDM_POWER_RET:
132 scu_pwr_st = SCU_PM_DORMANT;
134 case PWRDM_POWER_OFF:
135 scu_pwr_st = SCU_PM_POWEROFF;
138 case PWRDM_POWER_INACTIVE:
140 scu_pwr_st = SCU_PM_NORMAL;
144 __raw_writel(scu_pwr_st, pm_info->scu_sar_addr);
147 /* Helper functions for MPUSS OSWR */
148 static inline void mpuss_clear_prev_logic_pwrst(void)
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);
158 static inline void cpu_clear_prev_logic_pwrst(unsigned int 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);
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);
176 * omap4_mpuss_read_prev_context_state:
177 * Function returns the MPUSS previous context state
179 u32 omap4_mpuss_read_prev_context_state(void)
183 reg = omap4_prminst_read_inst_reg(OMAP4430_PRM_PARTITION,
184 OMAP4430_PRM_MPU_INST, OMAP4_RM_MPU_MPU_CONTEXT_OFFSET);
185 reg &= OMAP4430_LOSTCONTEXT_DFF_MASK;
190 * Store the CPU cluster state for L2X0 low power operations.
192 static void l2x0_pwrst_prepare(unsigned int cpu_id, unsigned int save_state)
194 struct omap4_cpu_pm_info *pm_info = &per_cpu(omap4_pm_info, cpu_id);
196 __raw_writel(save_state, pm_info->l2x0_sar_addr);
200 * Save the L2X0 AUXCTRL and POR value to SAR memory. Its used to
201 * in every restore MPUSS OFF path.
203 #ifdef CONFIG_CACHE_L2X0
204 static void save_l2x0_context(void)
207 void __iomem *l2x0_base = omap4_get_l2cache_base();
209 val = __raw_readl(l2x0_base + L2X0_AUX_CTRL);
210 __raw_writel(val, sar_base + L2X0_AUXCTRL_OFFSET);
211 val = __raw_readl(l2x0_base + L2X0_PREFETCH_CTRL);
212 __raw_writel(val, sar_base + L2X0_PREFETCH_CTRL_OFFSET);
216 static void save_l2x0_context(void)
221 * omap4_enter_lowpower: OMAP4 MPUSS Low Power Entry Function
222 * The purpose of this function is to manage low power programming
223 * of OMAP4 MPUSS subsystem
225 * @power_state: Low power state.
227 * MPUSS states for the context save:
229 * 0 - Nothing lost and no need to save: MPUSS INACTIVE
230 * 1 - CPUx L1 and logic lost: MPUSS CSWR
231 * 2 - CPUx L1 and logic lost + GIC lost: MPUSS OSWR
232 * 3 - CPUx L1 and logic lost + GIC + L2 lost: DEVICE OFF
234 int omap4_enter_lowpower(unsigned int cpu, unsigned int power_state)
236 struct omap4_cpu_pm_info *pm_info = &per_cpu(omap4_pm_info, cpu);
237 unsigned int save_state = 0;
238 unsigned int wakeup_cpu;
240 if (omap_rev() == OMAP4430_REV_ES1_0)
243 switch (power_state) {
245 case PWRDM_POWER_INACTIVE:
248 case PWRDM_POWER_OFF:
251 case PWRDM_POWER_RET:
254 * CPUx CSWR is invalid hardware state. Also CPUx OSWR
255 * doesn't make much scense, since logic is lost and $L1
256 * needs to be cleaned because of coherency. This makes
257 * CPUx OSWR equivalent to CPUX OFF and hence not supported
263 pwrdm_pre_transition(NULL);
266 * Check MPUSS next state and save interrupt controller if needed.
267 * In MPUSS OSWR or device OFF, interrupt controller contest is lost.
269 mpuss_clear_prev_logic_pwrst();
270 if ((pwrdm_read_next_pwrst(mpuss_pd) == PWRDM_POWER_RET) &&
271 (pwrdm_read_logic_retst(mpuss_pd) == PWRDM_POWER_OFF))
274 cpu_clear_prev_logic_pwrst(cpu);
275 pwrdm_set_next_pwrst(pm_info->pwrdm, power_state);
276 set_cpu_wakeup_addr(cpu, virt_to_phys(omap_pm_ops.resume));
277 omap_pm_ops.scu_prepare(cpu, power_state);
278 l2x0_pwrst_prepare(cpu, save_state);
281 * Call low level function with targeted low power state.
284 cpu_suspend(save_state, omap_pm_ops.finish_suspend);
286 omap_pm_ops.finish_suspend(save_state);
289 * Restore the CPUx power state to ON otherwise CPUx
290 * power domain can transitions to programmed low power
291 * state while doing WFI outside the low powe code. On
292 * secure devices, CPUx does WFI which can result in
295 wakeup_cpu = smp_processor_id();
296 pwrdm_set_next_pwrst(pm_info->pwrdm, PWRDM_POWER_ON);
298 pwrdm_post_transition(NULL);
304 * omap4_hotplug_cpu: OMAP4 CPU hotplug entry
306 * @power_state: CPU low power state.
308 int __cpuinit omap4_hotplug_cpu(unsigned int cpu, unsigned int power_state)
310 struct omap4_cpu_pm_info *pm_info = &per_cpu(omap4_pm_info, cpu);
311 unsigned int cpu_state = 0;
313 if (omap_rev() == OMAP4430_REV_ES1_0)
316 if (power_state == PWRDM_POWER_OFF)
319 pwrdm_clear_all_prev_pwrst(pm_info->pwrdm);
320 pwrdm_set_next_pwrst(pm_info->pwrdm, power_state);
321 set_cpu_wakeup_addr(cpu, virt_to_phys(pm_info->secondary_startup));
322 omap_pm_ops.scu_prepare(cpu, power_state);
325 * CPU never retuns back if targeted power state is OFF mode.
326 * CPU ONLINE follows normal CPU ONLINE ptah via
327 * omap_secondary_startup().
329 omap_pm_ops.finish_suspend(cpu_state);
331 pwrdm_set_next_pwrst(pm_info->pwrdm, PWRDM_POWER_ON);
337 * Initialise OMAP4 MPUSS
339 int __init omap4_mpuss_init(void)
341 struct omap4_cpu_pm_info *pm_info;
343 if (omap_rev() == OMAP4430_REV_ES1_0) {
344 WARN(1, "Power Management not supported on OMAP4430 ES1.0\n");
348 sar_base = omap4_get_sar_ram_base();
350 /* Initilaise per CPU PM information */
351 pm_info = &per_cpu(omap4_pm_info, 0x0);
352 pm_info->scu_sar_addr = sar_base + SCU_OFFSET0;
353 pm_info->wkup_sar_addr = sar_base + CPU0_WAKEUP_NS_PA_ADDR_OFFSET;
354 pm_info->l2x0_sar_addr = sar_base + L2X0_SAVE_OFFSET0;
355 pm_info->pwrdm = pwrdm_lookup("cpu0_pwrdm");
356 if (!pm_info->pwrdm) {
357 pr_err("Lookup failed for CPU0 pwrdm\n");
361 /* Clear CPU previous power domain state */
362 pwrdm_clear_all_prev_pwrst(pm_info->pwrdm);
363 cpu_clear_prev_logic_pwrst(0);
365 /* Initialise CPU0 power domain state to ON */
366 pwrdm_set_next_pwrst(pm_info->pwrdm, PWRDM_POWER_ON);
368 pm_info = &per_cpu(omap4_pm_info, 0x1);
369 pm_info->scu_sar_addr = sar_base + SCU_OFFSET1;
370 pm_info->wkup_sar_addr = sar_base + CPU1_WAKEUP_NS_PA_ADDR_OFFSET;
371 pm_info->l2x0_sar_addr = sar_base + L2X0_SAVE_OFFSET1;
372 if (cpu_is_omap446x())
373 pm_info->secondary_startup = omap_secondary_startup_4460;
375 pm_info->secondary_startup = omap_secondary_startup;
377 pm_info->pwrdm = pwrdm_lookup("cpu1_pwrdm");
378 if (!pm_info->pwrdm) {
379 pr_err("Lookup failed for CPU1 pwrdm\n");
383 /* Clear CPU previous power domain state */
384 pwrdm_clear_all_prev_pwrst(pm_info->pwrdm);
385 cpu_clear_prev_logic_pwrst(1);
387 /* Initialise CPU1 power domain state to ON */
388 pwrdm_set_next_pwrst(pm_info->pwrdm, PWRDM_POWER_ON);
390 mpuss_pd = pwrdm_lookup("mpu_pwrdm");
392 pr_err("Failed to lookup MPUSS power domain\n");
395 pwrdm_clear_all_prev_pwrst(mpuss_pd);
396 mpuss_clear_prev_logic_pwrst();
398 /* Save device type on scratchpad for low level code to use */
399 if (omap_type() != OMAP2_DEVICE_TYPE_GP)
400 __raw_writel(1, sar_base + OMAP_TYPE_OFFSET);
402 __raw_writel(0, sar_base + OMAP_TYPE_OFFSET);
406 if (cpu_is_omap44xx()) {
407 omap_pm_ops.finish_suspend = omap4_finish_suspend;
408 omap_pm_ops.resume = omap4_cpu_resume;
409 omap_pm_ops.scu_prepare = scu_pwrst_prepare;