diff options
Diffstat (limited to 'arch/powerpc/platforms/83xx/suspend.c')
-rw-r--r-- | arch/powerpc/platforms/83xx/suspend.c | 431 |
1 files changed, 431 insertions, 0 deletions
diff --git a/arch/powerpc/platforms/83xx/suspend.c b/arch/powerpc/platforms/83xx/suspend.c new file mode 100644 index 0000000000..9833c36bda --- /dev/null +++ b/arch/powerpc/platforms/83xx/suspend.c @@ -0,0 +1,431 @@ +// 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/platform_device.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); |