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-rw-r--r--arch/arm/mach-ux500/pm.c167
1 files changed, 167 insertions, 0 deletions
diff --git a/arch/arm/mach-ux500/pm.c b/arch/arm/mach-ux500/pm.c
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index 000000000000..1a468f0fd22e
--- /dev/null
+++ b/arch/arm/mach-ux500/pm.c
@@ -0,0 +1,167 @@
+/*
+ * Copyright (C) ST-Ericsson SA 2010-2013
+ * Author: Rickard Andersson <rickard.andersson@stericsson.com> for
+ *         ST-Ericsson.
+ * Author: Daniel Lezcano <daniel.lezcano@linaro.org> for Linaro.
+ * License terms: GNU General Public License (GPL) version 2
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/irqchip/arm-gic.h>
+#include <linux/delay.h>
+#include <linux/io.h>
+#include <linux/platform_data/arm-ux500-pm.h>
+
+#include "db8500-regs.h"
+
+/* ARM WFI Standby signal register */
+#define PRCM_ARM_WFI_STANDBY    (prcmu_base + 0x130)
+#define PRCM_ARM_WFI_STANDBY_WFI0		0x08
+#define PRCM_ARM_WFI_STANDBY_WFI1		0x10
+#define PRCM_IOCR		(prcmu_base + 0x310)
+#define PRCM_IOCR_IOFORCE			0x1
+
+/* Dual A9 core interrupt management unit registers */
+#define PRCM_A9_MASK_REQ	(prcmu_base + 0x328)
+#define PRCM_A9_MASK_REQ_PRCM_A9_MASK_REQ	0x1
+
+#define PRCM_A9_MASK_ACK	(prcmu_base + 0x32c)
+#define PRCM_ARMITMSK31TO0	(prcmu_base + 0x11c)
+#define PRCM_ARMITMSK63TO32	(prcmu_base + 0x120)
+#define PRCM_ARMITMSK95TO64	(prcmu_base + 0x124)
+#define PRCM_ARMITMSK127TO96	(prcmu_base + 0x128)
+#define PRCM_POWER_STATE_VAL	(prcmu_base + 0x25C)
+#define PRCM_ARMITVAL31TO0	(prcmu_base + 0x260)
+#define PRCM_ARMITVAL63TO32	(prcmu_base + 0x264)
+#define PRCM_ARMITVAL95TO64	(prcmu_base + 0x268)
+#define PRCM_ARMITVAL127TO96	(prcmu_base + 0x26C)
+
+static void __iomem *prcmu_base;
+
+/* This function decouple the gic from the prcmu */
+int prcmu_gic_decouple(void)
+{
+	u32 val = readl(PRCM_A9_MASK_REQ);
+
+	/* Set bit 0 register value to 1 */
+	writel(val | PRCM_A9_MASK_REQ_PRCM_A9_MASK_REQ,
+	       PRCM_A9_MASK_REQ);
+
+	/* Make sure the register is updated */
+	readl(PRCM_A9_MASK_REQ);
+
+	/* Wait a few cycles for the gic mask completion */
+	udelay(1);
+
+	return 0;
+}
+
+/* This function recouple the gic with the prcmu */
+int prcmu_gic_recouple(void)
+{
+	u32 val = readl(PRCM_A9_MASK_REQ);
+
+	/* Set bit 0 register value to 0 */
+	writel(val & ~PRCM_A9_MASK_REQ_PRCM_A9_MASK_REQ, PRCM_A9_MASK_REQ);
+
+	return 0;
+}
+
+#define PRCMU_GIC_NUMBER_REGS 5
+
+/*
+ * This function checks if there are pending irq on the gic. It only
+ * makes sense if the gic has been decoupled before with the
+ * db8500_prcmu_gic_decouple function. Disabling an interrupt only
+ * disables the forwarding of the interrupt to any CPU interface. It
+ * does not prevent the interrupt from changing state, for example
+ * becoming pending, or active and pending if it is already
+ * active. Hence, we have to check the interrupt is pending *and* is
+ * active.
+ */
+bool prcmu_gic_pending_irq(void)
+{
+	u32 pr; /* Pending register */
+	u32 er; /* Enable register */
+	void __iomem *dist_base = __io_address(U8500_GIC_DIST_BASE);
+	int i;
+
+	/* 5 registers. STI & PPI not skipped */
+	for (i = 0; i < PRCMU_GIC_NUMBER_REGS; i++) {
+
+		pr = readl_relaxed(dist_base + GIC_DIST_PENDING_SET + i * 4);
+		er = readl_relaxed(dist_base + GIC_DIST_ENABLE_SET + i * 4);
+
+		if (pr & er)
+			return true; /* There is a pending interrupt */
+	}
+
+	return false;
+}
+
+/*
+ * This function checks if there are pending interrupt on the
+ * prcmu which has been delegated to monitor the irqs with the
+ * db8500_prcmu_copy_gic_settings function.
+ */
+bool prcmu_pending_irq(void)
+{
+	u32 it, im;
+	int i;
+
+	for (i = 0; i < PRCMU_GIC_NUMBER_REGS - 1; i++) {
+		it = readl(PRCM_ARMITVAL31TO0 + i * 4);
+		im = readl(PRCM_ARMITMSK31TO0 + i * 4);
+		if (it & im)
+			return true; /* There is a pending interrupt */
+	}
+
+	return false;
+}
+
+/*
+ * This function checks if the specified cpu is in in WFI. It's usage
+ * makes sense only if the gic is decoupled with the db8500_prcmu_gic_decouple
+ * function. Of course passing smp_processor_id() to this function will
+ * always return false...
+ */
+bool prcmu_is_cpu_in_wfi(int cpu)
+{
+	return readl(PRCM_ARM_WFI_STANDBY) & cpu ? PRCM_ARM_WFI_STANDBY_WFI1 :
+		     PRCM_ARM_WFI_STANDBY_WFI0;
+}
+
+/*
+ * This function copies the gic SPI settings to the prcmu in order to
+ * monitor them and abort/finish the retention/off sequence or state.
+ */
+int prcmu_copy_gic_settings(void)
+{
+	u32 er; /* Enable register */
+	void __iomem *dist_base = __io_address(U8500_GIC_DIST_BASE);
+	int i;
+
+	/* We skip the STI and PPI */
+	for (i = 0; i < PRCMU_GIC_NUMBER_REGS - 1; i++) {
+		er = readl_relaxed(dist_base +
+				   GIC_DIST_ENABLE_SET + (i + 1) * 4);
+		writel(er, PRCM_ARMITMSK31TO0 + i * 4);
+	}
+
+	return 0;
+}
+
+void __init ux500_pm_init(u32 phy_base, u32 size)
+{
+	prcmu_base = ioremap(phy_base, size);
+	if (!prcmu_base) {
+		pr_err("could not remap PRCMU for PM functions\n");
+		return;
+	}
+	/*
+	 * On watchdog reboot the GIC is in some cases decoupled.
+	 * This will make sure that the GIC is correctly configured.
+	 */
+	prcmu_gic_recouple();
+}