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>
55 #include "omap4-sar-layout.h"
57 #include "prcm_mpu44xx.h"
58 #include "prminst44xx.h"
61 #include "prm-regbits-44xx.h"
65 struct omap4_cpu_pm_info {
66 struct powerdomain *pwrdm;
67 void __iomem *scu_sar_addr;
68 void __iomem *wkup_sar_addr;
69 void __iomem *l2x0_sar_addr;
72 static DEFINE_PER_CPU(struct omap4_cpu_pm_info, omap4_pm_info);
73 static struct powerdomain *mpuss_pd;
74 static void __iomem *sar_base;
77 * Program the wakeup routine address for the CPU0 and CPU1
78 * used for OFF or DORMANT wakeup.
80 static inline void set_cpu_wakeup_addr(unsigned int cpu_id, u32 addr)
82 struct omap4_cpu_pm_info *pm_info = &per_cpu(omap4_pm_info, cpu_id);
84 __raw_writel(addr, pm_info->wkup_sar_addr);
88 * Set the CPUx powerdomain's previous power state
90 static inline void set_cpu_next_pwrst(unsigned int cpu_id,
91 unsigned int power_state)
93 struct omap4_cpu_pm_info *pm_info = &per_cpu(omap4_pm_info, cpu_id);
95 pwrdm_set_next_pwrst(pm_info->pwrdm, power_state);
99 * Read CPU's previous power state
101 static inline unsigned int read_cpu_prev_pwrst(unsigned int cpu_id)
103 struct omap4_cpu_pm_info *pm_info = &per_cpu(omap4_pm_info, cpu_id);
105 return pwrdm_read_prev_pwrst(pm_info->pwrdm);
109 * Clear the CPUx powerdomain's previous power state
111 static inline void clear_cpu_prev_pwrst(unsigned int cpu_id)
113 struct omap4_cpu_pm_info *pm_info = &per_cpu(omap4_pm_info, cpu_id);
115 pwrdm_clear_all_prev_pwrst(pm_info->pwrdm);
119 * Store the SCU power status value to scratchpad memory
121 static void scu_pwrst_prepare(unsigned int cpu_id, unsigned int cpu_state)
123 struct omap4_cpu_pm_info *pm_info = &per_cpu(omap4_pm_info, cpu_id);
127 case PWRDM_POWER_RET:
128 scu_pwr_st = SCU_PM_DORMANT;
130 case PWRDM_POWER_OFF:
131 scu_pwr_st = SCU_PM_POWEROFF;
134 case PWRDM_POWER_INACTIVE:
136 scu_pwr_st = SCU_PM_NORMAL;
140 __raw_writel(scu_pwr_st, pm_info->scu_sar_addr);
143 /* Helper functions for MPUSS OSWR */
144 static inline void mpuss_clear_prev_logic_pwrst(void)
148 reg = omap4_prminst_read_inst_reg(OMAP4430_PRM_PARTITION,
149 OMAP4430_PRM_MPU_INST, OMAP4_RM_MPU_MPU_CONTEXT_OFFSET);
150 omap4_prminst_write_inst_reg(reg, OMAP4430_PRM_PARTITION,
151 OMAP4430_PRM_MPU_INST, OMAP4_RM_MPU_MPU_CONTEXT_OFFSET);
154 static inline void cpu_clear_prev_logic_pwrst(unsigned int cpu_id)
159 reg = omap4_prcm_mpu_read_inst_reg(OMAP4430_PRCM_MPU_CPU1_INST,
160 OMAP4_RM_CPU1_CPU1_CONTEXT_OFFSET);
161 omap4_prcm_mpu_write_inst_reg(reg, OMAP4430_PRCM_MPU_CPU1_INST,
162 OMAP4_RM_CPU1_CPU1_CONTEXT_OFFSET);
164 reg = omap4_prcm_mpu_read_inst_reg(OMAP4430_PRCM_MPU_CPU0_INST,
165 OMAP4_RM_CPU0_CPU0_CONTEXT_OFFSET);
166 omap4_prcm_mpu_write_inst_reg(reg, OMAP4430_PRCM_MPU_CPU0_INST,
167 OMAP4_RM_CPU0_CPU0_CONTEXT_OFFSET);
172 * omap4_mpuss_read_prev_context_state:
173 * Function returns the MPUSS previous context state
175 u32 omap4_mpuss_read_prev_context_state(void)
179 reg = omap4_prminst_read_inst_reg(OMAP4430_PRM_PARTITION,
180 OMAP4430_PRM_MPU_INST, OMAP4_RM_MPU_MPU_CONTEXT_OFFSET);
181 reg &= OMAP4430_LOSTCONTEXT_DFF_MASK;
186 * Store the CPU cluster state for L2X0 low power operations.
188 static void l2x0_pwrst_prepare(unsigned int cpu_id, unsigned int save_state)
190 struct omap4_cpu_pm_info *pm_info = &per_cpu(omap4_pm_info, cpu_id);
192 __raw_writel(save_state, pm_info->l2x0_sar_addr);
196 * Save the L2X0 AUXCTRL and POR value to SAR memory. Its used to
197 * in every restore MPUSS OFF path.
199 #ifdef CONFIG_CACHE_L2X0
200 static void save_l2x0_context(void)
203 void __iomem *l2x0_base = omap4_get_l2cache_base();
205 val = __raw_readl(l2x0_base + L2X0_AUX_CTRL);
206 __raw_writel(val, sar_base + L2X0_AUXCTRL_OFFSET);
207 val = __raw_readl(l2x0_base + L2X0_PREFETCH_CTRL);
208 __raw_writel(val, sar_base + L2X0_PREFETCH_CTRL_OFFSET);
211 static void save_l2x0_context(void)
216 * omap4_enter_lowpower: OMAP4 MPUSS Low Power Entry Function
217 * The purpose of this function is to manage low power programming
218 * of OMAP4 MPUSS subsystem
220 * @power_state: Low power state.
222 * MPUSS states for the context save:
224 * 0 - Nothing lost and no need to save: MPUSS INACTIVE
225 * 1 - CPUx L1 and logic lost: MPUSS CSWR
226 * 2 - CPUx L1 and logic lost + GIC lost: MPUSS OSWR
227 * 3 - CPUx L1 and logic lost + GIC + L2 lost: DEVICE OFF
229 int omap4_enter_lowpower(unsigned int cpu, unsigned int power_state)
231 unsigned int save_state = 0;
232 unsigned int wakeup_cpu;
234 if (omap_rev() == OMAP4430_REV_ES1_0)
237 switch (power_state) {
239 case PWRDM_POWER_INACTIVE:
242 case PWRDM_POWER_OFF:
245 case PWRDM_POWER_RET:
248 * CPUx CSWR is invalid hardware state. Also CPUx OSWR
249 * doesn't make much scense, since logic is lost and $L1
250 * needs to be cleaned because of coherency. This makes
251 * CPUx OSWR equivalent to CPUX OFF and hence not supported
257 pwrdm_pre_transition(NULL);
260 * Check MPUSS next state and save interrupt controller if needed.
261 * In MPUSS OSWR or device OFF, interrupt controller contest is lost.
263 mpuss_clear_prev_logic_pwrst();
264 if ((pwrdm_read_next_pwrst(mpuss_pd) == PWRDM_POWER_RET) &&
265 (pwrdm_read_logic_retst(mpuss_pd) == PWRDM_POWER_OFF))
268 cpu_clear_prev_logic_pwrst(cpu);
269 set_cpu_next_pwrst(cpu, power_state);
270 set_cpu_wakeup_addr(cpu, virt_to_phys(omap4_cpu_resume));
271 scu_pwrst_prepare(cpu, power_state);
272 l2x0_pwrst_prepare(cpu, save_state);
275 * Call low level function with targeted low power state.
277 cpu_suspend(save_state, omap4_finish_suspend);
280 * Restore the CPUx power state to ON otherwise CPUx
281 * power domain can transitions to programmed low power
282 * state while doing WFI outside the low powe code. On
283 * secure devices, CPUx does WFI which can result in
286 wakeup_cpu = smp_processor_id();
287 set_cpu_next_pwrst(wakeup_cpu, PWRDM_POWER_ON);
289 pwrdm_post_transition(NULL);
295 * omap4_hotplug_cpu: OMAP4 CPU hotplug entry
297 * @power_state: CPU low power state.
299 int __cpuinit omap4_hotplug_cpu(unsigned int cpu, unsigned int power_state)
301 unsigned int cpu_state = 0;
303 if (omap_rev() == OMAP4430_REV_ES1_0)
306 if (power_state == PWRDM_POWER_OFF)
309 clear_cpu_prev_pwrst(cpu);
310 set_cpu_next_pwrst(cpu, power_state);
311 set_cpu_wakeup_addr(cpu, virt_to_phys(omap_secondary_startup));
312 scu_pwrst_prepare(cpu, power_state);
315 * CPU never retuns back if targeted power state is OFF mode.
316 * CPU ONLINE follows normal CPU ONLINE ptah via
317 * omap_secondary_startup().
319 omap4_finish_suspend(cpu_state);
321 set_cpu_next_pwrst(cpu, PWRDM_POWER_ON);
327 * Initialise OMAP4 MPUSS
329 int __init omap4_mpuss_init(void)
331 struct omap4_cpu_pm_info *pm_info;
333 if (omap_rev() == OMAP4430_REV_ES1_0) {
334 WARN(1, "Power Management not supported on OMAP4430 ES1.0\n");
338 sar_base = omap4_get_sar_ram_base();
340 /* Initilaise per CPU PM information */
341 pm_info = &per_cpu(omap4_pm_info, 0x0);
342 pm_info->scu_sar_addr = sar_base + SCU_OFFSET0;
343 pm_info->wkup_sar_addr = sar_base + CPU0_WAKEUP_NS_PA_ADDR_OFFSET;
344 pm_info->l2x0_sar_addr = sar_base + L2X0_SAVE_OFFSET0;
345 pm_info->pwrdm = pwrdm_lookup("cpu0_pwrdm");
346 if (!pm_info->pwrdm) {
347 pr_err("Lookup failed for CPU0 pwrdm\n");
351 /* Clear CPU previous power domain state */
352 pwrdm_clear_all_prev_pwrst(pm_info->pwrdm);
353 cpu_clear_prev_logic_pwrst(0);
355 /* Initialise CPU0 power domain state to ON */
356 pwrdm_set_next_pwrst(pm_info->pwrdm, PWRDM_POWER_ON);
358 pm_info = &per_cpu(omap4_pm_info, 0x1);
359 pm_info->scu_sar_addr = sar_base + SCU_OFFSET1;
360 pm_info->wkup_sar_addr = sar_base + CPU1_WAKEUP_NS_PA_ADDR_OFFSET;
361 pm_info->l2x0_sar_addr = sar_base + L2X0_SAVE_OFFSET1;
362 pm_info->pwrdm = pwrdm_lookup("cpu1_pwrdm");
363 if (!pm_info->pwrdm) {
364 pr_err("Lookup failed for CPU1 pwrdm\n");
368 /* Clear CPU previous power domain state */
369 pwrdm_clear_all_prev_pwrst(pm_info->pwrdm);
370 cpu_clear_prev_logic_pwrst(1);
372 /* Initialise CPU1 power domain state to ON */
373 pwrdm_set_next_pwrst(pm_info->pwrdm, PWRDM_POWER_ON);
375 mpuss_pd = pwrdm_lookup("mpu_pwrdm");
377 pr_err("Failed to lookup MPUSS power domain\n");
380 pwrdm_clear_all_prev_pwrst(mpuss_pd);
381 mpuss_clear_prev_logic_pwrst();
383 /* Save device type on scratchpad for low level code to use */
384 if (omap_type() != OMAP2_DEVICE_TYPE_GP)
385 __raw_writel(1, sar_base + OMAP_TYPE_OFFSET);
387 __raw_writel(0, sar_base + OMAP_TYPE_OFFSET);