| // SPDX-License-Identifier: GPL-2.0-only |
| /* |
| * MPC83xx suspend support |
| * |
| * Author: Scott Wood <scottwood@freescale.com> |
| * |
| * 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 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 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 int pmc_probe(struct platform_device *ofdev) |
| { |
| struct device_node *np = ofdev->dev.of_node; |
| struct resource res; |
| const struct pmc_type *type; |
| int ret = 0; |
| |
| type = of_device_get_match_data(&ofdev->dev); |
| if (!type) |
| return -EINVAL; |
| |
| if (!of_device_is_available(np)) |
| return -ENODEV; |
| |
| has_deep_sleep = type->has_deep_sleep; |
| immrbase = get_immrbase(); |
| |
| 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 struct platform_driver pmc_driver = { |
| .driver = { |
| .name = "mpc83xx-pmc", |
| .of_match_table = pmc_match, |
| .suppress_bind_attrs = true, |
| }, |
| .probe = pmc_probe, |
| }; |
| |
| builtin_platform_driver(pmc_driver); |