1 files changed, 311 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 0000000..7567ee6
--- /dev/null
+++ b/arch/arm/mach-omap2/omap-wakeupgen.c
@@ -0,0 +1,311 @@
+/*
+ * OMAP WakeupGen Source file
+ *
+ * The WakeupGen unit is responsible for generating wakeup event from the
+ * incoming interrupts and enable bits. The WakeupGen is implemented in MPU
+ * always-On power domain. The WakeupGen consists of two sub-units, one for
+ * each CPU and manages only SPI interrupts. Hardware requirements is that
+ * the GIC and WakeupGen should be kept in sync for proper operation.
+ *
+ * Copyright (C) 2011 Texas Instruments, Inc.
+ * Written by 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 <asm/hardware/gic.h>
+
+#include <mach/omap-wakeupgen.h>
+#include <mach/omap4-common.h>
+
+#include "omap4-sar-layout.h"
+
+#define NR_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
+
+/* WakeupGen Base addres */
+static void __iomem *wakeupgen_base;
+static void __iomem *sar_base;
+static DEFINE_PER_CPU(u32 [NR_BANKS], irqmasks);
+static DEFINE_SPINLOCK(wakeupgen_lock);
+
+/*
+ * 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_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 wakeup gen register controls 32
+	 * interrupts. 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_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_BANKS; i++)
+		wakeupgen_writel(per_cpu(irqmasks, cpu)[i], i, cpu);
+}
+
+/*
+ * Architecture specific Mask extensiom
+ */
+static void wakeupgen_mask(struct irq_data *d)
+{
+	spin_lock(&wakeupgen_lock);
+	_wakeupgen_clear(d->irq, d->node);
+	spin_unlock(&wakeupgen_lock);
+}
+
+/*
+ * Architecture specific Unmask extensiom
+ */
+static void wakeupgen_unmask(struct irq_data *d)
+{
+	spin_lock(&wakeupgen_lock);
+	_wakeupgen_set(d->irq, d->node);
+	spin_unlock(&wakeupgen_lock);
+}
+
+/**
+ * omap_wakeupgen_irqmask_all() -  Mask or unmask interrupts
+ * @cpu - CPU ID
+ * @set - The IRQ register mask.
+ *	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 rgeisters to arrive at the correct masks
+ */
+void omap_wakeupgen_irqmask_all(unsigned int cpu, unsigned int set)
+{
+	if (omap_rev() == OMAP4430_REV_ES1_0)
+		return;
+
+	spin_lock(&wakeupgen_lock);
+	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(&wakeupgen_lock);
+}
+
+#ifdef CONFIG_PM
+/*
+ * Masking wakeup irqs is handled by the IRQCHIP_MASK_ON_SUSPEND flag,
+ * so no action is necessary in set_wake, but implement an empty handler
+ * here to prevent enable_irq_wake() returning an error.
+ */
+static int wakeupgen_set_wake(struct irq_data *d, unsigned int on)
+{
+	return 0;
+}
+#else
+#define wakeupgen_set_wake	NULL
+#endif
+
+/*
+ * Initialse the wakeupgen module
+ */
+int __init omap_wakeupgen_init(void)
+{
+	u8 i;
+
+	/* Not supported on 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 -ENODEV;
+
+	/* Clear all IRQ bitmasks at wakeupGen level */
+	for (i = 0; i < NR_BANKS; i++) {
+		wakeupgen_writel(0, i, CPU0_ID);
+		wakeupgen_writel(0, i, CPU1_ID);
+	}
+
+	/*
+	 * Override gic architecture specific fucntioms 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.irq_set_wake = wakeupgen_set_wake;
+	gic_arch_extn.flags = IRQCHIP_MASK_ON_SUSPEND;
+
+	return 0;
+}
+
+/**
+ * omap_wakeupgen_save() - WakeupGen context save function
+ *
+ * Save WakewupGen 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's located in
+ * always ON power domain. 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. Hence GIC and WakeupGen are saved
+ * and restored together.
+
+ * During normal operation, WakeupGen delivers external interrupts
+ * directly to the GIC. When the CPU asserts StandbyWFI, indicating
+ * it wants to enter lowpower state, the Standby Controller checks
+ * with the WakeupGen unit using the idlereq/idleack handshake to make
+ * sure there is no incoming interrupts.
+ */
+
+void omap_wakeupgen_save(void)
+{
+	u8 i;
+	u32 val;
+
+	if (omap_rev() == OMAP4430_REV_ES1_0)
+		return;
+
+	if (!sar_base)
+		sar_base = omap4_get_sar_ram_base();
+
+	for (i = 0; i < NR_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);
+}