Diff: targets/TARGET_Maxim/TARGET_MAX32620/sleep.c

Revision:

149:156823d33999

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/targets/TARGET_Maxim/TARGET_MAX32620/sleep.c	Fri Oct 28 11:17:30 2016 +0100
@@ -0,0 +1,219 @@
+/*******************************************************************************
+ * Copyright (C) 2016 Maxim Integrated Products, Inc., All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included
+ * in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+ * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+ * IN NO EVENT SHALL MAXIM INTEGRATED BE LIABLE FOR ANY CLAIM, DAMAGES
+ * OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * Except as contained in this notice, the name of Maxim Integrated
+ * Products, Inc. shall not be used except as stated in the Maxim Integrated
+ * Products, Inc. Branding Policy.
+ *
+ * The mere transfer of this software does not imply any licenses
+ * of trade secrets, proprietary technology, copyrights, patents,
+ * trademarks, maskwork rights, or any other form of intellectual
+ * property whatsoever. Maxim Integrated Products, Inc. retains all
+ * ownership rights.
+ *******************************************************************************
+ */
+
+#include "sleep_api.h"
+#include "pwrman_regs.h"
+#include "pwrseq_regs.h"
+#include "clkman_regs.h"
+#include "ioman_regs.h"
+#include "rtc_regs.h"
+#include "usb_regs.h"
+
+#define REVISION_A3 2
+#define REVISION_A4 3
+
+// USB state to be restored upon wakeup
+typedef struct {
+    uint32_t dev_cn;
+    uint32_t dev_inten;
+    uint32_t ep_base;
+    uint32_t ep[MXC_USB_NUM_EP];
+} usb_state_t;
+
+static mxc_uart_regs_t *stdio_uart = (mxc_uart_regs_t*)STDIO_UART;
+static int restore_usb;
+static usb_state_t usb_state;
+
+void sleep(void)
+{
+    // Normal sleep mode for ARM core
+    SCB->SCR = 0;
+
+    __DSB();
+    __WFI();
+}
+
+static void usb_sleep(void)
+{
+    int i;
+
+    if (MXC_USB->cn & MXC_F_USB_CN_USB_EN) {
+        // The USB module will not survive Deep Sleep.
+
+        // Save the USB state to restore it upon wakeup
+        usb_state.dev_cn = MXC_USB->dev_cn;
+        usb_state.dev_inten = MXC_USB->dev_inten;
+        usb_state.ep_base = MXC_USB->ep_base;
+        for (i = 0; i < MXC_USB_NUM_EP; i++) {
+            usb_state.ep[i] = MXC_USB->ep[i] & (MXC_F_USB_EP_DIR | MXC_F_USB_EP_BUF2 | MXC_F_USB_EP_INT_EN | MXC_F_USB_EP_NAK_EN);
+        }
+        restore_usb = 1;
+
+        // Shut down the USB module.
+        MXC_USB->dev_inten = 0;
+        MXC_USB->dev_cn = 0;
+        MXC_USB->cn = 0;
+        restore_usb = 1;   // USB should be restored upon wakeup
+    } else {
+        restore_usb = 0;
+    }
+}
+
+// Restore the USB module state.
+static void usb_wakeup(void)
+{
+    int i;
+
+    if (restore_usb) {
+        MXC_USB->cn = MXC_F_USB_CN_USB_EN;
+        MXC_USB->dev_cn = MXC_F_USB_DEV_CN_URST;
+        MXC_USB->dev_cn = 0;
+        for (i = 0; i < MXC_USB_NUM_EP; i++) {
+            MXC_USB->ep[i] = usb_state.ep[i];
+        }
+        MXC_USB->ep_base = usb_state.ep_base;
+        MXC_USB->dev_cn = usb_state.dev_cn;
+        MXC_USB->dev_inten = usb_state.dev_inten;
+        restore_usb = 0;
+    }
+}
+
+// Low-power stop mode
+void deepsleep(void)
+{
+    unsigned int part_rev = MXC_PWRMAN->mask_id0 & MXC_F_PWRMAN_MASK_ID0_REVISION_ID;
+
+    // Deep Sleep is not working properly on Revisions A3 and earlier
+    if (part_rev <= REVISION_A3) {
+        sleep();
+        return;
+    }
+
+    // Wait for all STDIO characters to be sent. The UART clock will stop.
+    while ((stdio_uart->tx_fifo_ctrl & MXC_F_UART_TX_FIFO_CTRL_FIFO_ENTRY) ||
+            !(stdio_uart->intfl & MXC_F_UART_INTFL_TX_DONE));
+
+    __disable_irq();
+
+    // Do not enter Deep Sleep if connected to VBUS
+    if (MXC_USB->dev_intfl & MXC_F_USB_DEV_INTFL_VBUS_ST) {
+        __enable_irq();
+        sleep();
+        return;
+    }
+
+    // The USB module will not survive Deep Sleep. Shut it down.
+    usb_sleep();
+
+    // Make sure RTC is not pending before sleeping, if its still synchronizing
+    // we might not wake up.
+    while (MXC_RTCTMR->ctrl & MXC_F_RTC_CTRL_PENDING);
+
+    // Clear any active GPIO Wake Up Events
+    if (MXC_PWRSEQ->flags & MXC_F_PWRSEQ_FLAGS_PWR_IOWAKEUP) {
+        // NOTE: These must be cleared before clearing IOWAKEUP
+        MXC_PWRSEQ->reg1 |= MXC_F_PWRSEQ_REG1_PWR_CLR_IO_EVENT_LATCH;
+        MXC_PWRSEQ->reg1 &= ~MXC_F_PWRSEQ_REG1_PWR_CLR_IO_EVENT_LATCH;
+
+        MXC_PWRSEQ->flags |= MXC_F_PWRSEQ_FLAGS_PWR_IOWAKEUP;
+    }
+
+    // Set the LP1 select bit so CPU goes to LP1 during SLEEPDEEP
+    if (part_rev == REVISION_A4) {
+        MXC_PWRSEQ->reg0 &= ~MXC_F_PWRSEQ_REG0_PWR_LP1; // A4 requires part to go to pseudo LP0
+    } else {
+        MXC_PWRSEQ->reg0 |= MXC_F_PWRSEQ_REG0_PWR_LP1;
+    }
+
+    // The SLEEPDEEP bit will cause a WFE() to trigger LP0/LP1 (depending on ..._REG0_PWR_LP1 state)
+    SCB->SCR |= SCB_SCR_SLEEPDEEP_Msk;
+
+    if (part_rev == REVISION_A4) {
+        // WORKAROUND: Toggle SVM bits, which send extra clocks to the power sequencer to fix retention controller
+        MXC_PWRSEQ->msk_flags |= MXC_F_PWRSEQ_MSK_FLAGS_PWR_TVDD12_RST_BAD;
+        MXC_PWRSEQ->reg0 &= ~(MXC_F_PWRSEQ_REG0_PWR_SVMTVDD12EN_RUN);
+        MXC_PWRSEQ->reg0 |= MXC_F_PWRSEQ_REG0_PWR_SVMTVDD12EN_RUN;
+        MXC_PWRSEQ->msk_flags &= ~MXC_F_PWRSEQ_MSK_FLAGS_PWR_TVDD12_RST_BAD;
+    }
+
+    // Enable Retention controller
+    MXC_PWRSEQ->retn_ctrl0 |= MXC_F_PWRSEQ_RETN_CTRL0_RETN_CTRL_EN;
+
+    // Clear the firstboot bit, which is generated by a POR event and locks out LPx modes
+    MXC_PWRSEQ->reg0 &= ~MXC_F_PWRSEQ_REG0_PWR_FIRST_BOOT;
+
+    // Freeze GPIO using MBUS so that it doesn't flail while digital core is asleep
+    MXC_PWRSEQ->reg1 |= MXC_F_PWRSEQ_REG1_PWR_MBUS_GATE;
+
+    // Dummy read to make sure SSB writes are complete
+    MXC_PWRSEQ->reg0 = MXC_PWRSEQ->reg0;
+
+    if (part_rev == REVISION_A4) {
+        // Note: ARM deep-sleep requires a specific sequence to clear event latches,
+        // otherwise the CPU will not enter sleep.
+        __SEV();
+        __WFE();
+        __WFI();
+    } else {
+        // Note: ARM deep-sleep requires a specific sequence to clear event latches,
+        //  otherwise the CPU will not enter sleep.
+        __SEV();
+        __WFE();
+        __WFE();
+    }
+
+    // We'll wakeup here ...
+
+    // Unfreeze the GPIO by clearing MBUS_GATE
+    MXC_PWRSEQ->reg1 &= ~MXC_F_PWRSEQ_REG1_PWR_MBUS_GATE;
+
+    usb_wakeup();
+
+    // Clear power sequencer event flags (write-1-to-clear)
+    // RTC and GPIO flags are cleared in their interrupts handlers
+    // NOTE: We are ignoring all of these potential wake up types
+    MXC_PWRSEQ->flags = (MXC_F_PWRSEQ_FLAGS_PWR_POWER_FAIL |
+                         MXC_F_PWRSEQ_FLAGS_PWR_BOOT_FAIL |
+                         MXC_F_PWRSEQ_FLAGS_PWR_FLASH_DISCHARGE |
+                         MXC_F_PWRSEQ_FLAGS_PWR_VDD12_RST_BAD |
+                         MXC_F_PWRSEQ_FLAGS_PWR_VDD18_RST_BAD |
+                         MXC_F_PWRSEQ_FLAGS_PWR_VRTC_RST_BAD |
+                         MXC_F_PWRSEQ_FLAGS_PWR_VDDB_RST_BAD |
+                         MXC_F_PWRSEQ_FLAGS_PWR_TVDD12_RST_BAD |
+                         MXC_F_PWRSEQ_FLAGS_PWR_POR18Z_FAIL_LATCH |
+                         MXC_F_PWRSEQ_FLAGS_PWR_USB_PLUG_WAKEUP |
+                         MXC_F_PWRSEQ_FLAGS_PWR_USB_REMOVE_WAKEUP |
+                         MXC_F_PWRSEQ_FLAGS_PWR_TVDD12_BAD);
+
+    __enable_irq();
+}