|  | // SPDX-License-Identifier: GPL-2.0-only | 
|  | /* | 
|  | * MPC83xx suspend support | 
|  | * | 
|  | * Author: Scott Wood <[email protected]> | 
|  | * | 
|  | * Copyright (c) 2006-2007 Freescale Semiconductor, Inc. | 
|  | */ | 
|  |  | 
|  | #include <linux/pm.h> | 
|  | #include <linux/types.h> | 
|  | #include <linux/ioport.h> | 
|  | #include <linux/interrupt.h> | 
|  | #include <linux/wait.h> | 
|  | #include <linux/sched/signal.h> | 
|  | #include <linux/kthread.h> | 
|  | #include <linux/freezer.h> | 
|  | #include <linux/suspend.h> | 
|  | #include <linux/fsl_devices.h> | 
|  | #include <linux/of_address.h> | 
|  | #include <linux/of_irq.h> | 
|  | #include <linux/of_platform.h> | 
|  | #include <linux/export.h> | 
|  |  | 
|  | #include <asm/reg.h> | 
|  | #include <asm/io.h> | 
|  | #include <asm/time.h> | 
|  | #include <asm/mpc6xx.h> | 
|  | #include <asm/switch_to.h> | 
|  |  | 
|  | #include <sysdev/fsl_soc.h> | 
|  |  | 
|  | #define PMCCR1_NEXT_STATE       0x0C /* Next state for power management */ | 
|  | #define PMCCR1_NEXT_STATE_SHIFT 2 | 
|  | #define PMCCR1_CURR_STATE       0x03 /* Current state for power management*/ | 
|  | #define IMMR_SYSCR_OFFSET       0x100 | 
|  | #define IMMR_RCW_OFFSET         0x900 | 
|  | #define RCW_PCI_HOST            0x80000000 | 
|  |  | 
|  | void mpc83xx_enter_deep_sleep(phys_addr_t immrbase); | 
|  |  | 
|  | struct mpc83xx_pmc { | 
|  | u32 config; | 
|  | #define PMCCR_DLPEN 2 /* DDR SDRAM low power enable */ | 
|  | #define PMCCR_SLPEN 1 /* System low power enable */ | 
|  |  | 
|  | u32 event; | 
|  | u32 mask; | 
|  | /* All but PMCI are deep-sleep only */ | 
|  | #define PMCER_GPIO   0x100 | 
|  | #define PMCER_PCI    0x080 | 
|  | #define PMCER_USB    0x040 | 
|  | #define PMCER_ETSEC1 0x020 | 
|  | #define PMCER_ETSEC2 0x010 | 
|  | #define PMCER_TIMER  0x008 | 
|  | #define PMCER_INT1   0x004 | 
|  | #define PMCER_INT2   0x002 | 
|  | #define PMCER_PMCI   0x001 | 
|  | #define PMCER_ALL    0x1FF | 
|  |  | 
|  | /* deep-sleep only */ | 
|  | u32 config1; | 
|  | #define PMCCR1_USE_STATE  0x80000000 | 
|  | #define PMCCR1_PME_EN     0x00000080 | 
|  | #define PMCCR1_ASSERT_PME 0x00000040 | 
|  | #define PMCCR1_POWER_OFF  0x00000020 | 
|  |  | 
|  | /* deep-sleep only */ | 
|  | u32 config2; | 
|  | }; | 
|  |  | 
|  | struct mpc83xx_rcw { | 
|  | u32 rcwlr; | 
|  | u32 rcwhr; | 
|  | }; | 
|  |  | 
|  | struct mpc83xx_clock { | 
|  | u32 spmr; | 
|  | u32 occr; | 
|  | u32 sccr; | 
|  | }; | 
|  |  | 
|  | struct mpc83xx_syscr { | 
|  | __be32 sgprl; | 
|  | __be32 sgprh; | 
|  | __be32 spridr; | 
|  | __be32 :32; | 
|  | __be32 spcr; | 
|  | __be32 sicrl; | 
|  | __be32 sicrh; | 
|  | }; | 
|  |  | 
|  | struct mpc83xx_saved { | 
|  | u32 sicrl; | 
|  | u32 sicrh; | 
|  | u32 sccr; | 
|  | }; | 
|  |  | 
|  | struct pmc_type { | 
|  | int has_deep_sleep; | 
|  | }; | 
|  |  | 
|  | static struct platform_device *pmc_dev; | 
|  | static int has_deep_sleep, deep_sleeping; | 
|  | static int pmc_irq; | 
|  | static struct mpc83xx_pmc __iomem *pmc_regs; | 
|  | static struct mpc83xx_clock __iomem *clock_regs; | 
|  | static struct mpc83xx_syscr __iomem *syscr_regs; | 
|  | static struct mpc83xx_saved saved_regs; | 
|  | static int is_pci_agent, wake_from_pci; | 
|  | static phys_addr_t immrbase; | 
|  | static int pci_pm_state; | 
|  | static DECLARE_WAIT_QUEUE_HEAD(agent_wq); | 
|  |  | 
|  | int fsl_deep_sleep(void) | 
|  | { | 
|  | return deep_sleeping; | 
|  | } | 
|  | EXPORT_SYMBOL(fsl_deep_sleep); | 
|  |  | 
|  | static int mpc83xx_change_state(void) | 
|  | { | 
|  | u32 curr_state; | 
|  | u32 reg_cfg1 = in_be32(&pmc_regs->config1); | 
|  |  | 
|  | if (is_pci_agent) { | 
|  | pci_pm_state = (reg_cfg1 & PMCCR1_NEXT_STATE) >> | 
|  | PMCCR1_NEXT_STATE_SHIFT; | 
|  | curr_state = reg_cfg1 & PMCCR1_CURR_STATE; | 
|  |  | 
|  | if (curr_state != pci_pm_state) { | 
|  | reg_cfg1 &= ~PMCCR1_CURR_STATE; | 
|  | reg_cfg1 |= pci_pm_state; | 
|  | out_be32(&pmc_regs->config1, reg_cfg1); | 
|  |  | 
|  | wake_up(&agent_wq); | 
|  | return 1; | 
|  | } | 
|  | } | 
|  |  | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | static irqreturn_t pmc_irq_handler(int irq, void *dev_id) | 
|  | { | 
|  | u32 event = in_be32(&pmc_regs->event); | 
|  | int ret = IRQ_NONE; | 
|  |  | 
|  | if (mpc83xx_change_state()) | 
|  | ret = IRQ_HANDLED; | 
|  |  | 
|  | if (event) { | 
|  | out_be32(&pmc_regs->event, event); | 
|  | ret = IRQ_HANDLED; | 
|  | } | 
|  |  | 
|  | return ret; | 
|  | } | 
|  |  | 
|  | static void mpc83xx_suspend_restore_regs(void) | 
|  | { | 
|  | out_be32(&syscr_regs->sicrl, saved_regs.sicrl); | 
|  | out_be32(&syscr_regs->sicrh, saved_regs.sicrh); | 
|  | out_be32(&clock_regs->sccr, saved_regs.sccr); | 
|  | } | 
|  |  | 
|  | static void mpc83xx_suspend_save_regs(void) | 
|  | { | 
|  | saved_regs.sicrl = in_be32(&syscr_regs->sicrl); | 
|  | saved_regs.sicrh = in_be32(&syscr_regs->sicrh); | 
|  | saved_regs.sccr = in_be32(&clock_regs->sccr); | 
|  | } | 
|  |  | 
|  | static int mpc83xx_suspend_enter(suspend_state_t state) | 
|  | { | 
|  | int ret = -EAGAIN; | 
|  |  | 
|  | /* Don't go to sleep if there's a race where pci_pm_state changes | 
|  | * between the agent thread checking it and the PM code disabling | 
|  | * interrupts. | 
|  | */ | 
|  | if (wake_from_pci) { | 
|  | if (pci_pm_state != (deep_sleeping ? 3 : 2)) | 
|  | goto out; | 
|  |  | 
|  | out_be32(&pmc_regs->config1, | 
|  | in_be32(&pmc_regs->config1) | PMCCR1_PME_EN); | 
|  | } | 
|  |  | 
|  | /* Put the system into low-power mode and the RAM | 
|  | * into self-refresh mode once the core goes to | 
|  | * sleep. | 
|  | */ | 
|  |  | 
|  | out_be32(&pmc_regs->config, PMCCR_SLPEN | PMCCR_DLPEN); | 
|  |  | 
|  | /* If it has deep sleep (i.e. it's an 831x or compatible), | 
|  | * disable power to the core upon entering sleep mode.  This will | 
|  | * require going through the boot firmware upon a wakeup event. | 
|  | */ | 
|  |  | 
|  | if (deep_sleeping) { | 
|  | mpc83xx_suspend_save_regs(); | 
|  |  | 
|  | out_be32(&pmc_regs->mask, PMCER_ALL); | 
|  |  | 
|  | out_be32(&pmc_regs->config1, | 
|  | in_be32(&pmc_regs->config1) | PMCCR1_POWER_OFF); | 
|  |  | 
|  | enable_kernel_fp(); | 
|  |  | 
|  | mpc83xx_enter_deep_sleep(immrbase); | 
|  |  | 
|  | out_be32(&pmc_regs->config1, | 
|  | in_be32(&pmc_regs->config1) & ~PMCCR1_POWER_OFF); | 
|  |  | 
|  | out_be32(&pmc_regs->mask, PMCER_PMCI); | 
|  |  | 
|  | mpc83xx_suspend_restore_regs(); | 
|  | } else { | 
|  | out_be32(&pmc_regs->mask, PMCER_PMCI); | 
|  |  | 
|  | mpc6xx_enter_standby(); | 
|  | } | 
|  |  | 
|  | ret = 0; | 
|  |  | 
|  | out: | 
|  | out_be32(&pmc_regs->config1, | 
|  | in_be32(&pmc_regs->config1) & ~PMCCR1_PME_EN); | 
|  |  | 
|  | return ret; | 
|  | } | 
|  |  | 
|  | static void mpc83xx_suspend_end(void) | 
|  | { | 
|  | deep_sleeping = 0; | 
|  | } | 
|  |  | 
|  | static int mpc83xx_suspend_valid(suspend_state_t state) | 
|  | { | 
|  | return state == PM_SUSPEND_STANDBY || state == PM_SUSPEND_MEM; | 
|  | } | 
|  |  | 
|  | static int mpc83xx_suspend_begin(suspend_state_t state) | 
|  | { | 
|  | switch (state) { | 
|  | case PM_SUSPEND_STANDBY: | 
|  | deep_sleeping = 0; | 
|  | return 0; | 
|  |  | 
|  | case PM_SUSPEND_MEM: | 
|  | if (has_deep_sleep) | 
|  | deep_sleeping = 1; | 
|  |  | 
|  | return 0; | 
|  |  | 
|  | default: | 
|  | return -EINVAL; | 
|  | } | 
|  | } | 
|  |  | 
|  | static int agent_thread_fn(void *data) | 
|  | { | 
|  | while (1) { | 
|  | wait_event_interruptible(agent_wq, pci_pm_state >= 2); | 
|  | try_to_freeze(); | 
|  |  | 
|  | if (signal_pending(current) || pci_pm_state < 2) | 
|  | continue; | 
|  |  | 
|  | /* With a preemptible kernel (or SMP), this could race with | 
|  | * a userspace-driven suspend request.  It's probably best | 
|  | * to avoid mixing the two with such a configuration (or | 
|  | * else fix it by adding a mutex to state_store that we can | 
|  | * synchronize with). | 
|  | */ | 
|  |  | 
|  | wake_from_pci = 1; | 
|  |  | 
|  | pm_suspend(pci_pm_state == 3 ? PM_SUSPEND_MEM : | 
|  | PM_SUSPEND_STANDBY); | 
|  |  | 
|  | wake_from_pci = 0; | 
|  | } | 
|  |  | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | static void mpc83xx_set_agent(void) | 
|  | { | 
|  | out_be32(&pmc_regs->config1, PMCCR1_USE_STATE); | 
|  | out_be32(&pmc_regs->mask, PMCER_PMCI); | 
|  |  | 
|  | kthread_run(agent_thread_fn, NULL, "PCI power mgt"); | 
|  | } | 
|  |  | 
|  | static int mpc83xx_is_pci_agent(void) | 
|  | { | 
|  | struct mpc83xx_rcw __iomem *rcw_regs; | 
|  | int ret; | 
|  |  | 
|  | rcw_regs = ioremap(get_immrbase() + IMMR_RCW_OFFSET, | 
|  | sizeof(struct mpc83xx_rcw)); | 
|  |  | 
|  | if (!rcw_regs) | 
|  | return -ENOMEM; | 
|  |  | 
|  | ret = !(in_be32(&rcw_regs->rcwhr) & RCW_PCI_HOST); | 
|  |  | 
|  | iounmap(rcw_regs); | 
|  | return ret; | 
|  | } | 
|  |  | 
|  | static const struct platform_suspend_ops mpc83xx_suspend_ops = { | 
|  | .valid = mpc83xx_suspend_valid, | 
|  | .begin = mpc83xx_suspend_begin, | 
|  | .enter = mpc83xx_suspend_enter, | 
|  | .end = mpc83xx_suspend_end, | 
|  | }; | 
|  |  | 
|  | static const struct of_device_id pmc_match[]; | 
|  | static int pmc_probe(struct platform_device *ofdev) | 
|  | { | 
|  | const struct of_device_id *match; | 
|  | struct device_node *np = ofdev->dev.of_node; | 
|  | struct resource res; | 
|  | const struct pmc_type *type; | 
|  | int ret = 0; | 
|  |  | 
|  | match = of_match_device(pmc_match, &ofdev->dev); | 
|  | if (!match) | 
|  | return -EINVAL; | 
|  |  | 
|  | type = match->data; | 
|  |  | 
|  | if (!of_device_is_available(np)) | 
|  | return -ENODEV; | 
|  |  | 
|  | has_deep_sleep = type->has_deep_sleep; | 
|  | immrbase = get_immrbase(); | 
|  | pmc_dev = ofdev; | 
|  |  | 
|  | is_pci_agent = mpc83xx_is_pci_agent(); | 
|  | if (is_pci_agent < 0) | 
|  | return is_pci_agent; | 
|  |  | 
|  | ret = of_address_to_resource(np, 0, &res); | 
|  | if (ret) | 
|  | return -ENODEV; | 
|  |  | 
|  | pmc_irq = irq_of_parse_and_map(np, 0); | 
|  | if (pmc_irq) { | 
|  | ret = request_irq(pmc_irq, pmc_irq_handler, IRQF_SHARED, | 
|  | "pmc", ofdev); | 
|  |  | 
|  | if (ret) | 
|  | return -EBUSY; | 
|  | } | 
|  |  | 
|  | pmc_regs = ioremap(res.start, sizeof(*pmc_regs)); | 
|  |  | 
|  | if (!pmc_regs) { | 
|  | ret = -ENOMEM; | 
|  | goto out; | 
|  | } | 
|  |  | 
|  | ret = of_address_to_resource(np, 1, &res); | 
|  | if (ret) { | 
|  | ret = -ENODEV; | 
|  | goto out_pmc; | 
|  | } | 
|  |  | 
|  | clock_regs = ioremap(res.start, sizeof(*clock_regs)); | 
|  |  | 
|  | if (!clock_regs) { | 
|  | ret = -ENOMEM; | 
|  | goto out_pmc; | 
|  | } | 
|  |  | 
|  | if (has_deep_sleep) { | 
|  | syscr_regs = ioremap(immrbase + IMMR_SYSCR_OFFSET, | 
|  | sizeof(*syscr_regs)); | 
|  | if (!syscr_regs) { | 
|  | ret = -ENOMEM; | 
|  | goto out_syscr; | 
|  | } | 
|  | } | 
|  |  | 
|  | if (is_pci_agent) | 
|  | mpc83xx_set_agent(); | 
|  |  | 
|  | suspend_set_ops(&mpc83xx_suspend_ops); | 
|  | return 0; | 
|  |  | 
|  | out_syscr: | 
|  | iounmap(clock_regs); | 
|  | out_pmc: | 
|  | iounmap(pmc_regs); | 
|  | out: | 
|  | if (pmc_irq) | 
|  | free_irq(pmc_irq, ofdev); | 
|  |  | 
|  | return ret; | 
|  | } | 
|  |  | 
|  | static int pmc_remove(struct platform_device *ofdev) | 
|  | { | 
|  | return -EPERM; | 
|  | }; | 
|  |  | 
|  | static struct pmc_type pmc_types[] = { | 
|  | { | 
|  | .has_deep_sleep = 1, | 
|  | }, | 
|  | { | 
|  | .has_deep_sleep = 0, | 
|  | } | 
|  | }; | 
|  |  | 
|  | static const struct of_device_id pmc_match[] = { | 
|  | { | 
|  | .compatible = "fsl,mpc8313-pmc", | 
|  | .data = &pmc_types[0], | 
|  | }, | 
|  | { | 
|  | .compatible = "fsl,mpc8349-pmc", | 
|  | .data = &pmc_types[1], | 
|  | }, | 
|  | {} | 
|  | }; | 
|  |  | 
|  | static struct platform_driver pmc_driver = { | 
|  | .driver = { | 
|  | .name = "mpc83xx-pmc", | 
|  | .of_match_table = pmc_match, | 
|  | }, | 
|  | .probe = pmc_probe, | 
|  | .remove = pmc_remove | 
|  | }; | 
|  |  | 
|  | builtin_platform_driver(pmc_driver); |