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-rw-r--r--arch/powerpc/platforms/83xx/suspend.c431
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 000000000..3fa8979ac
--- /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/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);
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-24 19:31:32 +0000