Use V307 flash

src/device.h

@@ -5,10 +5,11 @@
 
 #include "arch.h"
 
-#define MG_DEVICE_NONE 0      // Dummy system
-#define MG_DEVICE_STM32H5 1   // STM32 H5
-#define MG_DEVICE_STM32H7 2   // STM32 H7
-#define MG_DEVICE_CUSTOM 100  // Custom implementation
+#define MG_DEVICE_NONE 0        // Dummy system
+#define MG_DEVICE_STM32H5 1     // STM32 H5
+#define MG_DEVICE_STM32H7 2     // STM32 H7
+#define MG_DEVICE_CH32V307 100  // WCH CH32V307
+#define MG_DEVICE_CUSTOM 1000   // Custom implementation
 
 #ifndef MG_DEVICE
 #define MG_DEVICE MG_DEVICE_NONE

src/device_ch32v307.c

@@ -0,0 +1,78 @@
+#include "device.h"
+#include "log.h"
+
+#if MG_DEVICE == MG_DEVICE_CH32V307
+// RM: https://www.wch-ic.com/downloads/CH32FV2x_V3xRM_PDF.html
+
+#define FLASH_BASE 0x40022000
+#define FLASH_ACTLR (FLASH_BASE + 0)
+#define FLASH_KEYR (FLASH_BASE + 4)
+#define FLASH_OBKEYR (FLASH_BASE + 8)
+#define FLASH_STATR (FLASH_BASE + 12)
+#define FLASH_CTLR (FLASH_BASE + 16)
+#define FLASH_ADDR (FLASH_BASE + 20)
+#define FLASH_OBR (FLASH_BASE + 28)
+#define FLASH_WPR (FLASH_BASE + 32)
+
+void *mg_flash_start(void) {
+  return (void *) 0x08000000;
+}
+size_t mg_flash_size(void) {
+  return 480 * 1024;  // First 320k is 0-wait
+}
+size_t mg_flash_sector_size(void) {
+  return 4096;
+}
+size_t mg_flash_write_align(void) {
+  return 4;
+}
+int mg_flash_bank(void) {
+  return 0;
+}
+void mg_device_reset(void) {
+  *((volatile uint32_t *) 0xbeef0000) |= 1U << 7;  // NVIC_SystemReset()
+}
+static void flash_unlock(void) {
+  static bool unlocked;
+  if (unlocked == false) {
+    MG_REG(FLASH_KEYR) = 0x45670123;
+    MG_REG(FLASH_KEYR) = 0xcdef89ab;
+    unlocked = true;
+  }
+}
+static void flash_wait(void) {
+  while (MG_REG(FLASH_STATR) & MG_BIT(0)) (void) 0;
+}
+
+bool mg_flash_erase(void *addr) {
+  //MG_INFO(("%p", addr));
+  flash_unlock();
+  flash_wait();
+  MG_REG(FLASH_ADDR) = (uint32_t) addr;
+  MG_REG(FLASH_CTLR) |= MG_BIT(1) | MG_BIT(6);  // PER | STRT;
+  flash_wait();
+  return true;
+}
+
+static bool is_page_boundary(const void *addr) {
+  uint32_t val = (uint32_t) addr;
+  return (val & (mg_flash_sector_size() - 1)) == 0;
+}
+
+bool mg_flash_write(void *addr, const void *buf, size_t len) {
+  //MG_INFO(("%p %p %lu", addr, buf, len));
+  //mg_hexdump(buf, len);
+  flash_unlock();
+  const uint16_t *src = (uint16_t *) buf, *end = &src[len / 2];
+  uint16_t *dst = (uint16_t *) addr;
+  MG_REG(FLASH_CTLR) |= MG_BIT(0);  // Set PG
+  //MG_INFO(("CTLR: %#lx", MG_REG(FLASH_CTLR)));
+  while (src < end) {
+    if (is_page_boundary(dst)) mg_flash_erase(dst);
+    *dst++ = *src++;
+    flash_wait();
+  }
+  MG_REG(FLASH_CTLR) &= ~MG_BIT(0);  // Clear PG
+  return true;
+}
+#endif