diff options
Diffstat (limited to 'arch/arm/mach-omap2/omap-wakeupgen.c')
| -rw-r--r-- | arch/arm/mach-omap2/omap-wakeupgen.c | 389 |
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 new file mode 100644 index 000000000000..d3d8971d7f30 --- /dev/null +++ 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; +} |