From f3464d90cc72add643a3532708b934dcb85c3714 Mon Sep 17 00:00:00 2001
From: Martin Luessi <mluessi@gmail.com>
Date: Fri, 8 Jul 2022 06:46:08 -0700
Subject: [PATCH] Flashfs: Add support for asynchronous complete erase

---
 src/main/fc/tasks.c   |  5 +++++
 src/main/io/flashfs.c | 48 +++++++++++++++++++++++++++++++------------
 src/main/io/flashfs.h |  1 +
 3 files changed, 41 insertions(+), 13 deletions(-)

diff --git a/src/main/fc/tasks.c b/src/main/fc/tasks.c
index 7c0407dfa0..de630702b4 100644
--- a/src/main/fc/tasks.c
+++ b/src/main/fc/tasks.c
@@ -61,6 +61,7 @@
 #include "io/asyncfatfs/asyncfatfs.h"
 #include "io/beeper.h"
 #include "io/dashboard.h"
+#include "io/flashfs.h"
 #include "io/gps.h"
 #include "io/ledstrip.h"
 #include "io/piniobox.h"
@@ -126,6 +127,10 @@ static void taskMain(timeUs_t currentTimeUs)
 #ifdef USE_SDCARD
     afatfs_poll();
 #endif
+
+#ifdef USE_FLASHFS
+    flashfsEraseAsync();
+#endif
 }
 
 static void taskHandleSerial(timeUs_t currentTimeUs)
diff --git a/src/main/io/flashfs.c b/src/main/io/flashfs.c
index 8e8c16bd57..9cd7e869f9 100644
--- a/src/main/io/flashfs.c
+++ b/src/main/io/flashfs.c
@@ -41,12 +41,20 @@
 #include "build/debug.h"
 #include "common/printf.h"
 #include "drivers/flash.h"
+#include "drivers/light_led.h"
 
 #include "io/flashfs.h"
 
+typedef enum {
+    FLASHFS_IDLE,
+    FLASHFS_ERASING,
+} flashfsState_e;
+
 static const flashPartition_t *flashPartition = NULL;
 static const flashGeometry_t *flashGeometry = NULL;
 static uint32_t flashfsSize = 0;
+static flashfsState_e flashfsState = FLASHFS_IDLE;
+static flashSector_t eraseSectorCurrent = 0;
 
 static DMA_DATA_ZERO_INIT uint8_t flashWriteBuffer[FLASHFS_WRITE_BUFFER_SIZE];
 
@@ -110,17 +118,9 @@ void flashfsEraseCompletely(void)
         if (doFullErase) {
             flashEraseCompletely();
         } else {
-
-            // TODO - the partial sector-based erase needs to be completely reworked.
-            // All calls to flashfsEraseCompletely() currently expect the erase to run
-            // asynchronously and return immediately. The current implementation performs
-            // the erase synchronously and doesn't return until complete. This breaks calls
-            // from MSP and runtime mode-switched erasing.
-
-            for (flashSector_t sectorIndex = flashPartition->startSector; sectorIndex <= flashPartition->endSector; sectorIndex++) {
-                uint32_t sectorAddress = sectorIndex * flashGeometry->sectorSize;
-                flashEraseSector(sectorAddress);
-            }
+            // start asynchronous erase of all sectors
+            eraseSectorCurrent = flashPartition->startSector;
+            flashfsState = FLASHFS_ERASING;
         }
     }
 
@@ -160,9 +160,9 @@ void flashfsEraseRange(uint32_t start, uint32_t end)
  */
 bool flashfsIsReady(void)
 {
-    // Check for flash chip existence first, then check if ready.
+    // Check for flash chip existence first, then check if idle and ready.
 
-    return (flashfsIsSupported() && flashIsReady());
+    return (flashfsIsSupported() && (flashfsState == FLASHFS_IDLE) && flashIsReady());
 }
 
 bool flashfsIsSupported(void)
@@ -407,6 +407,28 @@ void flashfsFlushSync(void)
     while (!flashIsReady());
 }
 
+/**
+ *  Asynchronously erase the flash: Check if ready and then erase sector.
+ */
+void flashfsEraseAsync(void)
+{
+    if (flashfsState == FLASHFS_ERASING) {
+        if ((flashfsIsSupported() && flashIsReady())) {
+            if (eraseSectorCurrent <= flashPartition->endSector) {
+                // Erase sector
+                uint32_t sectorAddress = eraseSectorCurrent * flashGeometry->sectorSize;
+                flashEraseSector(sectorAddress);
+                eraseSectorCurrent++;
+                LED1_TOGGLE;
+            } else {
+                // Done erasing
+                flashfsState = FLASHFS_IDLE;
+                LED1_OFF;
+            }
+        }
+    }
+}
+
 void flashfsSeekAbs(uint32_t offset)
 {
     flashfsFlushSync();
diff --git a/src/main/io/flashfs.h b/src/main/io/flashfs.h
index 0817d26b05..510efdb560 100644
--- a/src/main/io/flashfs.h
+++ b/src/main/io/flashfs.h
@@ -46,6 +46,7 @@ int flashfsReadAbs(uint32_t offset, uint8_t *data, unsigned int len);
 
 bool flashfsFlushAsync(bool force);
 void flashfsFlushSync(void);
+void flashfsEraseAsync(void);
 
 void flashfsClose(void);
 void flashfsInit(void);