From ad9d89a7563826a493bfec4e2164f9df0e8e997b Mon Sep 17 00:00:00 2001
From: Ruben Dashyan <ruben.dashyan@numworks.com>
Date: Mon, 14 Jan 2019 16:43:49 +0100
Subject: [PATCH] [ion/f730] Shutdown external flash

---
 ion/src/f730/device.cpp         |  1 +
 ion/src/f730/external_flash.cpp | 33 +++++++++++++++++++++++++++++++--
 ion/src/f730/external_flash.h   |  7 ++++++-
 3 files changed, 38 insertions(+), 3 deletions(-)

diff --git a/ion/src/f730/device.cpp b/ion/src/f730/device.cpp
index 1958d8e4c..06956b4ed 100644
--- a/ion/src/f730/device.cpp
+++ b/ion/src/f730/device.cpp
@@ -228,6 +228,7 @@ void shutdownPeripherals(bool keepLEDAwake) {
 #if USE_SD_CARD
   SDCard::Device::shutdown();
 #endif
+  ExternalFlash::Device::shutdown();
   USB::Device::shutdown();
   Battery::Device::shutdown();
   if (!keepLEDAwake) {
diff --git a/ion/src/f730/external_flash.cpp b/ion/src/f730/external_flash.cpp
index 0ebe55c17..46a3c99b1 100644
--- a/ion/src/f730/external_flash.cpp
+++ b/ion/src/f730/external_flash.cpp
@@ -1,4 +1,5 @@
 #include "external_flash.h"
+#include "timing.h"
 
 namespace Ion {
 namespace ExternalFlash {
@@ -205,6 +206,12 @@ void init() {
   initChip();
 }
 
+void shutdown() {
+  shutdownChip();
+  shutdownQSPI();
+  shutdownGPIO();
+}
+
 void initGPIO() {
   for(const GPIOPin & g : QSPIPins) {
     g.group().OSPEEDR()->setOutputSpeed(g.pin(), GPIO::OSPEEDR::OutputSpeed::High);
@@ -213,9 +220,17 @@ void initGPIO() {
   }
 }
 
+void shutdownGPIO() {
+  for(const GPIOPin & g : QSPIPins) {
+    g.group().OSPEEDR()->setOutputSpeed(g.pin(), GPIO::OSPEEDR::OutputSpeed::Low);
+    g.group().MODER()->setMode(g.pin(), GPIO::MODER::Mode::Analog);
+    g.group().PUPDR()->setPull(g.pin(), GPIO::PUPDR::Pull::None);
+  }
+}
+
 void initQSPI() {
   // Enable QUADSPI AHB3 peripheral clock
-  RCC.AHB3ENR()->setQSPIEN(true);
+  RCC.AHB3ENR()->setQSPIEN(true); // TODO: move in Device::initClocks
   // Configure controller for target device
   class QUADSPI::DCR dcr(0);
   dcr.setFSIZE(NumberOfAddressBitsInChip - 1);
@@ -228,10 +243,15 @@ void initQSPI() {
   QUADSPI.CR()->set(cr);
 }
 
+void shutdownQSPI() {
+  RCC.AHB3ENR()->setQSPIEN(false); // TODO: move in Device::shutdownClocks
+}
+
 void initChip() {
+  static bool firstPass = true;
   /* The chip initially expects commands in SPI mode. We need to use SPI to tell
    * it to switch to QPI. */
-  if (DefaultOperatingMode == QUADSPI::CCR::OperatingMode::Quad) {
+  if (firstPass && DefaultOperatingMode == QUADSPI::CCR::OperatingMode::Quad) {
     send_command(Command::WriteEnable, QUADSPI::CCR::OperatingMode::Single);
     ExternalFlashStatusRegister::StatusRegister2 statusRegister2(0);
     statusRegister2.setQE(true);
@@ -252,10 +272,19 @@ void initChip() {
       readParameters.setP5(true);
       send_write_command(Command::SetReadParameters, reinterpret_cast<uint8_t *>(FlashAddressSpaceSize), reinterpret_cast<uint8_t *>(&readParameters), sizeof(readParameters));
     }
+    firstPass = false;
+  } else {
+    // TODO
   }
   set_as_memory_mapped();
 }
 
+void shutdownChip() {
+  unset_memory_mapped_mode();
+  send_command(Command::DeepPowerDown);
+  Timing::usleep(100); // TODO should be 3us when usleep adjusted
+}
+
 int SectorAtAddress(uint32_t address) {
   int i = address >> NumberOfAddressBitsIn64KbyteBlock;
   if (i >= NumberOfSectors) {
diff --git a/ion/src/f730/external_flash.h b/ion/src/f730/external_flash.h
index 1b102027d..2f4af8b01 100644
--- a/ion/src/f730/external_flash.h
+++ b/ion/src/f730/external_flash.h
@@ -36,8 +36,11 @@ void init();
 void shutdown();
 
 void initGPIO();
+void shutdownGPIO();
 void initQSPI();
+void shutdownQSPI();
 void initChip();
+void shutdownChip();
 
 void MassErase();
 
@@ -61,7 +64,9 @@ enum class Command : uint8_t {
   // Erase the whole chip or a 64-Kbyte block as being "1"
   ChipErase = 0xC7,
   Erase64KbyteBlock = 0xD8,
-  SetReadParameters = 0xC0
+  SetReadParameters = 0xC0,
+  DeepPowerDown = 0xB9,
+  ReleaseDeepPowerDown = 0xAB
 };
 
 constexpr static uint32_t QSPIBaseAddress = 0x90000000;