From ed4c7b358b6221cf9c4bc3fd80fc2e9031a742dc Mon Sep 17 00:00:00 2001
From: Mateusz Faderewski <sc@mateuszfaderewski.pl>
Date: Tue, 21 Feb 2023 22:25:01 +0100
Subject: [PATCH] Changed SC64 firmware version checking

---
 src/flashcart/sc64/sc64.c          | 15 +++++++++------
 src/flashcart/sc64/sc64_internal.c | 15 ++++++++-------
 src/flashcart/sc64/sc64_internal.h |  2 +-
 src/main.c                         | 17 ++++-------------
 4 files changed, 22 insertions(+), 27 deletions(-)

diff --git a/src/flashcart/sc64/sc64.c b/src/flashcart/sc64/sc64.c
index d63afe5c..41b6e38e 100644
--- a/src/flashcart/sc64/sc64.c
+++ b/src/flashcart/sc64/sc64.c
@@ -18,7 +18,8 @@
 #define SHADOW_ADDRESS              (0x1FFC0000)
 #define EEPROM_ADDRESS              (0x1FFE2000)
 
-#define MIN_SUPPORTED_API_VERSION   (1)
+#define SUPPORTED_MAJOR_VERSION     (2)
+#define SUPPORTED_MINOR_VERSION     (12)
 
 
 static flashcart_error_t load_to_flash (FIL *fil, void *address, size_t size, UINT *br) {
@@ -52,19 +53,21 @@ static flashcart_error_t load_to_flash (FIL *fil, void *address, size_t size, UI
 
 
 static flashcart_error_t sc64_init (void) {
-    uint32_t api_version;
+    uint16_t major;
+    uint16_t minor;
 
     sc64_unlock();
 
     if (!sc64_check_presence()) {
         return FLASHCART_ERROR_UNSUPPORTED;
     }
-
-    if (sc64_get_api_version(&api_version) != SC64_OK) {
+    if (sc64_get_version(&major, &minor) != SC64_OK) {
         return FLASHCART_ERROR_OUTDATED;
     }
-
-    if (api_version < MIN_SUPPORTED_API_VERSION) {
+    if (major != SUPPORTED_MAJOR_VERSION) {
+        return FLASHCART_ERROR_OUTDATED;
+    }
+    if (minor < SUPPORTED_MINOR_VERSION) {
         return FLASHCART_ERROR_OUTDATED;
     }
 
diff --git a/src/flashcart/sc64/sc64_internal.c b/src/flashcart/sc64/sc64_internal.c
index 7230aecb..b381ec26 100644
--- a/src/flashcart/sc64/sc64_internal.c
+++ b/src/flashcart/sc64/sc64_internal.c
@@ -6,7 +6,7 @@
 typedef struct {
     uint32_t SR_CMD;
     uint32_t DATA[2];
-    uint32_t VERSION;
+    uint32_t IDENTIFIER;
     uint32_t KEY;
 } sc64_regs_t;
 
@@ -17,7 +17,7 @@ typedef struct {
 #define SC64_SR_CMD_ERROR       (1 << 30)
 #define SC64_SR_CPU_BUSY        (1 << 31)
 
-#define SC64_VERSION_2          (0x53437632)
+#define SC64_V2_IDENTIFIER      (0x53437632)
 
 #define SC64_KEY_RESET          (0x00000000UL)
 #define SC64_KEY_UNLOCK_1       (0x5F554E4CUL)
@@ -26,7 +26,7 @@ typedef struct {
 
 
 typedef enum {
-    CMD_ID_API_VERSION_GET      = 'V',
+    CMD_ID_VERSION_GET          = 'V',
     CMD_ID_CONFIG_GET           = 'c',
     CMD_ID_CONFIG_SET           = 'C',
     CMD_ID_WRITEBACK_SD_INFO    = 'W',
@@ -75,7 +75,7 @@ void sc64_lock (void) {
 }
 
 bool sc64_check_presence (void) {
-    return (io_read((uint32_t) (&SC64_REGS->VERSION)) == SC64_VERSION_2);
+    return (io_read((uint32_t) (&SC64_REGS->IDENTIFIER)) == SC64_V2_IDENTIFIER);
 }
 
 void sc64_read_data (void *src, void *dst, size_t length) {
@@ -90,10 +90,11 @@ void sc64_write_data (void *src, void *dst, size_t length) {
     dma_wait();
 }
 
-sc64_error_t sc64_get_api_version (uint32_t *api_version) {
-    sc64_cmd_t cmd = { .id = CMD_ID_API_VERSION_GET };
+sc64_error_t sc64_get_version (uint16_t *major, uint16_t *minor) {
+    sc64_cmd_t cmd = { .id = CMD_ID_VERSION_GET };
     sc64_error_t error = sc64_execute_cmd(&cmd);
-    *api_version = cmd.rsp[0];
+    *major = ((cmd.rsp[0] >> 16) & 0xFFFF);
+    *minor = (cmd.rsp[0] & 0xFFFF);
     return error;
 }
 
diff --git a/src/flashcart/sc64/sc64_internal.h b/src/flashcart/sc64/sc64_internal.h
index 2b818f98..a24918a9 100644
--- a/src/flashcart/sc64/sc64_internal.h
+++ b/src/flashcart/sc64/sc64_internal.h
@@ -60,7 +60,7 @@ void sc64_lock (void);
 bool sc64_check_presence (void);
 void sc64_read_data (void *src, void *dst, size_t length);
 void sc64_write_data (void *src, void *dst, size_t length);
-sc64_error_t sc64_get_api_version (uint32_t *api_version);
+sc64_error_t sc64_get_version (uint16_t *major, uint16_t *minor);
 sc64_error_t sc64_get_config (sc64_cfg_t cfg, void *value);
 sc64_error_t sc64_set_config (sc64_cfg_t cfg, uint32_t value);
 sc64_error_t sc64_writeback_enable (void *address);
diff --git a/src/main.c b/src/main.c
index deb7a1ec..b228d833 100644
--- a/src/main.c
+++ b/src/main.c
@@ -10,20 +10,11 @@
 
 static void init (void) {
     assertf(usb_initialize() != CART_NONE, "No flashcart was detected");
-    switch (flashcart_init()) {
-        case FLASHCART_OK:
-            break;
-        case FLASHCART_ERROR_OUTDATED:
-            assertf(false, "Outdated flashcart firmware");
-            break;
-        case FLASHCART_ERROR_UNSUPPORTED:
-            assertf(false, "Unsupported flashcart");
-            break;
-        default:
-            assertf(false, "Unknown error while initializing flashcart");
-            break;
-    }
     assertf(debug_init_sdfs("sd:/", -1), "Couldn't initialize SD card");
+    flashcart_error_t error = flashcart_init();
+    assertf(error != FLASHCART_ERROR_OUTDATED, "Outdated flashcart firmware");
+    assertf(error != FLASHCART_ERROR_UNSUPPORTED, "Unsupported flashcart");
+    assertf(error == FLASHCART_OK, "Unknown error while initializing flashcart");
 }
 
 static void deinit (void) {