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-rw-r--r--kernel/arch/arm/mach-ux500/pm.c198
1 files changed, 198 insertions, 0 deletions
diff --git a/kernel/arch/arm/mach-ux500/pm.c b/kernel/arch/arm/mach-ux500/pm.c
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index 000000000..2cb587b50
--- /dev/null
+++ b/kernel/arch/arm/mach-ux500/pm.c
@@ -0,0 +1,198 @@
+/*
+ * 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.
+ * Author: Ulf Hansson <ulf.hansson@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/suspend.h>
+#include <linux/platform_data/arm-ux500-pm.h>
+
+#include "db8500-regs.h"
+#include "pm_domains.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;
+}
+
+#ifdef CONFIG_SUSPEND
+static int ux500_suspend_enter(suspend_state_t state)
+{
+ cpu_do_idle();
+ return 0;
+}
+
+static int ux500_suspend_valid(suspend_state_t state)
+{
+ return state == PM_SUSPEND_MEM || state == PM_SUSPEND_STANDBY;
+}
+
+static const struct platform_suspend_ops ux500_suspend_ops = {
+ .enter = ux500_suspend_enter,
+ .valid = ux500_suspend_valid,
+};
+#define UX500_SUSPEND_OPS (&ux500_suspend_ops)
+#else
+#define UX500_SUSPEND_OPS NULL
+#endif
+
+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();
+
+ /* Set up ux500 suspend callbacks. */
+ suspend_set_ops(UX500_SUSPEND_OPS);
+
+ /* Initialize ux500 power domains */
+ ux500_pm_domains_init();
+}