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-rw-r--r--arch/arm/mach-omap2/omap-wakeupgen.c389
1 files changed, 389 insertions, 0 deletions
diff --git a/arch/arm/mach-omap2/omap-wakeupgen.c b/arch/arm/mach-omap2/omap-wakeupgen.c
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index 00000000000..d3d8971d7f3
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+++ b/arch/arm/mach-omap2/omap-wakeupgen.c
@@ -0,0 +1,389 @@
+/*
+ * OMAP WakeupGen Source file
+ *
+ * OMAP WakeupGen is the interrupt controller extension used along
+ * with ARM GIC to wake the CPU out from low power states on
+ * external interrupts. It is responsible for generating wakeup
+ * event from the incoming interrupts and enable bits. It is
+ * implemented in MPU always ON power domain. During normal operation,
+ * WakeupGen delivers external interrupts directly to the GIC.
+ *
+ * Copyright (C) 2011 Texas Instruments, Inc.
+ * Santosh Shilimkar <santosh.shilimkar@ti.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/irq.h>
+#include <linux/platform_device.h>
+#include <linux/cpu.h>
+#include <linux/notifier.h>
+#include <linux/cpu_pm.h>
+
+#include <asm/hardware/gic.h>
+
+#include <mach/omap-wakeupgen.h>
+#include <mach/omap-secure.h>
+
+#include "omap4-sar-layout.h"
+#include "common.h"
+
+#define NR_REG_BANKS 4
+#define MAX_IRQS 128
+#define WKG_MASK_ALL 0x00000000
+#define WKG_UNMASK_ALL 0xffffffff
+#define CPU_ENA_OFFSET 0x400
+#define CPU0_ID 0x0
+#define CPU1_ID 0x1
+
+static void __iomem *wakeupgen_base;
+static void __iomem *sar_base;
+static DEFINE_PER_CPU(u32 [NR_REG_BANKS], irqmasks);
+static DEFINE_SPINLOCK(wakeupgen_lock);
+static unsigned int irq_target_cpu[NR_IRQS];
+
+/*
+ * Static helper functions.
+ */
+static inline u32 wakeupgen_readl(u8 idx, u32 cpu)
+{
+ return __raw_readl(wakeupgen_base + OMAP_WKG_ENB_A_0 +
+ (cpu * CPU_ENA_OFFSET) + (idx * 4));
+}
+
+static inline void wakeupgen_writel(u32 val, u8 idx, u32 cpu)
+{
+ __raw_writel(val, wakeupgen_base + OMAP_WKG_ENB_A_0 +
+ (cpu * CPU_ENA_OFFSET) + (idx * 4));
+}
+
+static inline void sar_writel(u32 val, u32 offset, u8 idx)
+{
+ __raw_writel(val, sar_base + offset + (idx * 4));
+}
+
+static void _wakeupgen_set_all(unsigned int cpu, unsigned int reg)
+{
+ u8 i;
+
+ for (i = 0; i < NR_REG_BANKS; i++)
+ wakeupgen_writel(reg, i, cpu);
+}
+
+static inline int _wakeupgen_get_irq_info(u32 irq, u32 *bit_posn, u8 *reg_index)
+{
+ unsigned int spi_irq;
+
+ /*
+ * PPIs and SGIs are not supported.
+ */
+ if (irq < OMAP44XX_IRQ_GIC_START)
+ return -EINVAL;
+
+ /*
+ * Subtract the GIC offset.
+ */
+ spi_irq = irq - OMAP44XX_IRQ_GIC_START;
+ if (spi_irq > MAX_IRQS) {
+ pr_err("omap wakeupGen: Invalid IRQ%d\n", irq);
+ return -EINVAL;
+ }
+
+ /*
+ * Each WakeupGen register controls 32 interrupt.
+ * i.e. 1 bit per SPI IRQ
+ */
+ *reg_index = spi_irq >> 5;
+ *bit_posn = spi_irq %= 32;
+
+ return 0;
+}
+
+static void _wakeupgen_clear(unsigned int irq, unsigned int cpu)
+{
+ u32 val, bit_number;
+ u8 i;
+
+ if (_wakeupgen_get_irq_info(irq, &bit_number, &i))
+ return;
+
+ val = wakeupgen_readl(i, cpu);
+ val &= ~BIT(bit_number);
+ wakeupgen_writel(val, i, cpu);
+}
+
+static void _wakeupgen_set(unsigned int irq, unsigned int cpu)
+{
+ u32 val, bit_number;
+ u8 i;
+
+ if (_wakeupgen_get_irq_info(irq, &bit_number, &i))
+ return;
+
+ val = wakeupgen_readl(i, cpu);
+ val |= BIT(bit_number);
+ wakeupgen_writel(val, i, cpu);
+}
+
+static void _wakeupgen_save_masks(unsigned int cpu)
+{
+ u8 i;
+
+ for (i = 0; i < NR_REG_BANKS; i++)
+ per_cpu(irqmasks, cpu)[i] = wakeupgen_readl(i, cpu);
+}
+
+static void _wakeupgen_restore_masks(unsigned int cpu)
+{
+ u8 i;
+
+ for (i = 0; i < NR_REG_BANKS; i++)
+ wakeupgen_writel(per_cpu(irqmasks, cpu)[i], i, cpu);
+}
+
+/*
+ * Architecture specific Mask extension
+ */
+static void wakeupgen_mask(struct irq_data *d)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&wakeupgen_lock, flags);
+ _wakeupgen_clear(d->irq, irq_target_cpu[d->irq]);
+ spin_unlock_irqrestore(&wakeupgen_lock, flags);
+}
+
+/*
+ * Architecture specific Unmask extension
+ */
+static void wakeupgen_unmask(struct irq_data *d)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&wakeupgen_lock, flags);
+ _wakeupgen_set(d->irq, irq_target_cpu[d->irq]);
+ spin_unlock_irqrestore(&wakeupgen_lock, flags);
+}
+
+/*
+ * Mask or unmask all interrupts on given CPU.
+ * 0 = Mask all interrupts on the 'cpu'
+ * 1 = Unmask all interrupts on the 'cpu'
+ * Ensure that the initial mask is maintained. This is faster than
+ * iterating through GIC registers to arrive at the correct masks.
+ */
+static void wakeupgen_irqmask_all(unsigned int cpu, unsigned int set)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&wakeupgen_lock, flags);
+ if (set) {
+ _wakeupgen_save_masks(cpu);
+ _wakeupgen_set_all(cpu, WKG_MASK_ALL);
+ } else {
+ _wakeupgen_set_all(cpu, WKG_UNMASK_ALL);
+ _wakeupgen_restore_masks(cpu);
+ }
+ spin_unlock_irqrestore(&wakeupgen_lock, flags);
+}
+
+#ifdef CONFIG_CPU_PM
+/*
+ * Save WakeupGen interrupt context in SAR BANK3. Restore is done by
+ * ROM code. WakeupGen IP is integrated along with GIC to manage the
+ * interrupt wakeups from CPU low power states. It manages
+ * masking/unmasking of Shared peripheral interrupts(SPI). So the
+ * interrupt enable/disable control should be in sync and consistent
+ * at WakeupGen and GIC so that interrupts are not lost.
+ */
+static void irq_save_context(void)
+{
+ u32 i, val;
+
+ if (omap_rev() == OMAP4430_REV_ES1_0)
+ return;
+
+ if (!sar_base)
+ sar_base = omap4_get_sar_ram_base();
+
+ for (i = 0; i < NR_REG_BANKS; i++) {
+ /* Save the CPUx interrupt mask for IRQ 0 to 127 */
+ val = wakeupgen_readl(i, 0);
+ sar_writel(val, WAKEUPGENENB_OFFSET_CPU0, i);
+ val = wakeupgen_readl(i, 1);
+ sar_writel(val, WAKEUPGENENB_OFFSET_CPU1, i);
+
+ /*
+ * Disable the secure interrupts for CPUx. The restore
+ * code blindly restores secure and non-secure interrupt
+ * masks from SAR RAM. Secure interrupts are not suppose
+ * to be enabled from HLOS. So overwrite the SAR location
+ * so that the secure interrupt remains disabled.
+ */
+ sar_writel(0x0, WAKEUPGENENB_SECURE_OFFSET_CPU0, i);
+ sar_writel(0x0, WAKEUPGENENB_SECURE_OFFSET_CPU1, i);
+ }
+
+ /* Save AuxBoot* registers */
+ val = __raw_readl(wakeupgen_base + OMAP_AUX_CORE_BOOT_0);
+ __raw_writel(val, sar_base + AUXCOREBOOT0_OFFSET);
+ val = __raw_readl(wakeupgen_base + OMAP_AUX_CORE_BOOT_0);
+ __raw_writel(val, sar_base + AUXCOREBOOT1_OFFSET);
+
+ /* Save SyncReq generation logic */
+ val = __raw_readl(wakeupgen_base + OMAP_AUX_CORE_BOOT_0);
+ __raw_writel(val, sar_base + AUXCOREBOOT0_OFFSET);
+ val = __raw_readl(wakeupgen_base + OMAP_AUX_CORE_BOOT_0);
+ __raw_writel(val, sar_base + AUXCOREBOOT1_OFFSET);
+
+ /* Save SyncReq generation logic */
+ val = __raw_readl(wakeupgen_base + OMAP_PTMSYNCREQ_MASK);
+ __raw_writel(val, sar_base + PTMSYNCREQ_MASK_OFFSET);
+ val = __raw_readl(wakeupgen_base + OMAP_PTMSYNCREQ_EN);
+ __raw_writel(val, sar_base + PTMSYNCREQ_EN_OFFSET);
+
+ /* Set the Backup Bit Mask status */
+ val = __raw_readl(sar_base + SAR_BACKUP_STATUS_OFFSET);
+ val |= SAR_BACKUP_STATUS_WAKEUPGEN;
+ __raw_writel(val, sar_base + SAR_BACKUP_STATUS_OFFSET);
+}
+
+/*
+ * Clear WakeupGen SAR backup status.
+ */
+void irq_sar_clear(void)
+{
+ u32 val;
+ val = __raw_readl(sar_base + SAR_BACKUP_STATUS_OFFSET);
+ val &= ~SAR_BACKUP_STATUS_WAKEUPGEN;
+ __raw_writel(val, sar_base + SAR_BACKUP_STATUS_OFFSET);
+}
+
+/*
+ * Save GIC and Wakeupgen interrupt context using secure API
+ * for HS/EMU devices.
+ */
+static void irq_save_secure_context(void)
+{
+ u32 ret;
+ ret = omap_secure_dispatcher(OMAP4_HAL_SAVEGIC_INDEX,
+ FLAG_START_CRITICAL,
+ 0, 0, 0, 0, 0);
+ if (ret != API_HAL_RET_VALUE_OK)
+ pr_err("GIC and Wakeupgen context save failed\n");
+}
+#endif
+
+#ifdef CONFIG_HOTPLUG_CPU
+static int __cpuinit irq_cpu_hotplug_notify(struct notifier_block *self,
+ unsigned long action, void *hcpu)
+{
+ unsigned int cpu = (unsigned int)hcpu;
+
+ switch (action) {
+ case CPU_ONLINE:
+ wakeupgen_irqmask_all(cpu, 0);
+ break;
+ case CPU_DEAD:
+ wakeupgen_irqmask_all(cpu, 1);
+ break;
+ }
+ return NOTIFY_OK;
+}
+
+static struct notifier_block __refdata irq_hotplug_notifier = {
+ .notifier_call = irq_cpu_hotplug_notify,
+};
+
+static void __init irq_hotplug_init(void)
+{
+ register_hotcpu_notifier(&irq_hotplug_notifier);
+}
+#else
+static void __init irq_hotplug_init(void)
+{}
+#endif
+
+#ifdef CONFIG_CPU_PM
+static int irq_notifier(struct notifier_block *self, unsigned long cmd, void *v)
+{
+ switch (cmd) {
+ case CPU_CLUSTER_PM_ENTER:
+ if (omap_type() == OMAP2_DEVICE_TYPE_GP)
+ irq_save_context();
+ else
+ irq_save_secure_context();
+ break;
+ case CPU_CLUSTER_PM_EXIT:
+ if (omap_type() == OMAP2_DEVICE_TYPE_GP)
+ irq_sar_clear();
+ break;
+ }
+ return NOTIFY_OK;
+}
+
+static struct notifier_block irq_notifier_block = {
+ .notifier_call = irq_notifier,
+};
+
+static void __init irq_pm_init(void)
+{
+ cpu_pm_register_notifier(&irq_notifier_block);
+}
+#else
+static void __init irq_pm_init(void)
+{}
+#endif
+
+/*
+ * Initialise the wakeupgen module.
+ */
+int __init omap_wakeupgen_init(void)
+{
+ int i;
+ unsigned int boot_cpu = smp_processor_id();
+
+ /* Not supported on OMAP4 ES1.0 silicon */
+ if (omap_rev() == OMAP4430_REV_ES1_0) {
+ WARN(1, "WakeupGen: Not supported on OMAP4430 ES1.0\n");
+ return -EPERM;
+ }
+
+ /* Static mapping, never released */
+ wakeupgen_base = ioremap(OMAP44XX_WKUPGEN_BASE, SZ_4K);
+ if (WARN_ON(!wakeupgen_base))
+ return -ENOMEM;
+
+ /* Clear all IRQ bitmasks at wakeupGen level */
+ for (i = 0; i < NR_REG_BANKS; i++) {
+ wakeupgen_writel(0, i, CPU0_ID);
+ wakeupgen_writel(0, i, CPU1_ID);
+ }
+
+ /*
+ * Override GIC architecture specific functions to add
+ * OMAP WakeupGen interrupt controller along with GIC
+ */
+ gic_arch_extn.irq_mask = wakeupgen_mask;
+ gic_arch_extn.irq_unmask = wakeupgen_unmask;
+ gic_arch_extn.flags = IRQCHIP_MASK_ON_SUSPEND | IRQCHIP_SKIP_SET_WAKE;
+
+ /*
+ * FIXME: Add support to set_smp_affinity() once the core
+ * GIC code has necessary hooks in place.
+ */
+
+ /* Associate all the IRQs to boot CPU like GIC init does. */
+ for (i = 0; i < NR_IRQS; i++)
+ irq_target_cpu[i] = boot_cpu;
+
+ irq_hotplug_init();
+ irq_pm_init();
+
+ return 0;
+}