Implement svcGetCFWInfo in place of svc 0x2e (which is stubbed). Luma3DS now boots ca. 1.5s faster

Fix bug in pin.c where the START button wasn't recognized as well.

source/firm.c

@@ -301,6 +301,8 @@ static inline void patchNativeFirm(u32 firmVersion, FirmwareSource nandType, u32
         //Restore svcBackdoor
         reimplementSvcBackdoor((u8 *)firm + section[1].offset, section[1].size);
     }
+
+    implementSvcGetCFWInfo((u8 *)firm + section[1].offset, section[1].size);
 }
 
 static inline void patchLegacyFirm(FirmwareType firmType)

source/patches.c

@@ -24,6 +24,49 @@
 #include "memory.h"
 #include "config.h"
 #include "../build/rebootpatch.h"
+#include "../build/svcGetCFWInfopatch.h"
+#include "fs.h"
+
+static u32 *arm11ExceptionsPage = NULL;
+static u32 *arm11SvcTable = NULL;
+static u32 *arm11SvcHandler = NULL;
+
+static u8 *freeK11Space = NULL; //other than the one used for svcBackdoor
+
+static void findArm11ExceptionsPageAndSvcHandlerAndTable(u8 *pos, u32 size)
+{
+    const u8 arm11ExceptionsPagePattern[] = {0x00, 0xB0, 0x9C, 0xE5};
+    
+    if(arm11ExceptionsPage == NULL) arm11ExceptionsPage = (u32 *)memsearch(pos, arm11ExceptionsPagePattern, size, 4) - 0xB;
+    if((arm11SvcTable == NULL || arm11SvcHandler == NULL) && arm11ExceptionsPage != NULL)
+    {
+        u32 svcOffset = (-((arm11ExceptionsPage[2] & 0xFFFFFF) << 2) & (0xFFFFFF << 2)) - 8; //Branch offset + 8 for prefetch
+        arm11SvcHandler = arm11SvcTable = (u32 *)(pos + *(u32 *)(pos + 0xFFFF0008 - svcOffset - 0xFFF00000 + 8) - 0xFFF00000); //SVC handler address
+        while(*arm11SvcTable) arm11SvcTable++; //Look for SVC0 (NULL)
+    }
+}
+
+static void findFreeK11Space(u8 *pos, u32 size)
+{
+    if(freeK11Space == NULL)
+    {
+        const u8 bogus_pattern[] = { 0x1E, 0xFF, 0x2F, 0xE1, 0x1E, 0xFF, 0x2F, 0xE1, 0x1E, 0xFF, 
+                                     0x2F, 0xE1, 0x00, 0x10, 0xA0, 0xE3, 0x00, 0x10, 0xC0, 0xE5, 
+                                     0x1E, 0xFF, 0x2F, 0xE1 };
+        
+        u32 *someSpace = (u32 *)memsearch(pos, bogus_pattern, size, 24);
+
+        // We couldn't find the place where to begin our search of an empty block
+        if (someSpace == NULL)
+            return;
+
+        // Advance until we reach the padding area (filled with 0xFF)
+        u32 *freeSpace;
+        for(freeSpace = someSpace; *freeSpace != 0xFFFFFFFF; freeSpace++);
+
+        freeK11Space = (u8 *)freeSpace;
+    }
+}
 
 u8 *getProcess9(u8 *pos, u32 size, u32 *process9Size, u32 *process9MemAddr)
 {
@@ -111,25 +154,65 @@ void reimplementSvcBackdoor(u8 *pos, u32 size)
                                  0x00, 0xD0, 0xA0, 0xE1,  //mov   sp, r0
                                  0x11, 0xFF, 0x2F, 0xE1}; //bx    r1
 
-    const u8 pattern[] = {0x00, 0xB0, 0x9C, 0xE5}; //cpsid aif
-    
-    u32 *exceptionsPage = (u32 *)memsearch(pos, pattern, size, 4) - 0xB;
+    findArm11ExceptionsPageAndSvcHandlerAndTable(pos, size);
 
-    u32 svcOffset = (-((exceptionsPage[2] & 0xFFFFFF) << 2) & (0xFFFFFF << 2)) - 8; //Branch offset + 8 for prefetch
-    u32 *svcTable = (u32 *)(pos + *(u32 *)(pos + 0xFFFF0008 - svcOffset - 0xFFF00000 + 8) - 0xFFF00000); //SVC handler address
-    while(*svcTable) svcTable++; //Look for SVC0 (NULL)
-
-    if(svcTable[0x7B] == 0)
+    if(!arm11SvcTable[0x7B])
     {
         u32 *freeSpace;
-        for(freeSpace = exceptionsPage; *freeSpace != 0xFFFFFFFF; freeSpace++);
+        for(freeSpace = arm11ExceptionsPage; *freeSpace != 0xFFFFFFFF; freeSpace++);
 
         memcpy(freeSpace, svcBackdoor, 40);
 
-        svcTable[0x7B] = 0xFFFF0000 + ((u8 *)freeSpace - (u8 *)exceptionsPage);
+        arm11SvcTable[0x7B] = 0xFFFF0000 + ((u8 *)freeSpace - (u8 *)arm11ExceptionsPage);
     }
 }
 
+extern u32 config;
+
+void implementSvcGetCFWInfo(u8 *pos, u32 size)
+{
+    typedef struct __attribute__((packed))
+    {
+        char magic[4];
+        
+        u8 versionMajor;
+        u8 versionMinor;
+        u8 versionBuild;
+        u8 flags;
+
+        u32 commitHash;
+
+        u32 config;
+    } CFWInfo;
+
+    const char *rev = REVISION;
+    bool isRelease = false;
+
+    findArm11ExceptionsPageAndSvcHandlerAndTable(pos, size);
+    findFreeK11Space(pos, size);
+    
+    memcpy(freeK11Space, svcGetCFWInfo, svcGetCFWInfo_size);
+
+    CFWInfo *info = (CFWInfo *)memsearch(freeK11Space, "LUMA", svcGetCFWInfo_size, 4);
+
+    info->commitHash = COMMIT_HASH;
+    info->config = config;
+    info->versionMajor = (u8)(rev[1] - '0');
+    info->versionMinor = (u8)(rev[3] - '0');
+    if(rev[4] == '.')
+    {
+        info->versionBuild = (u8)(rev[5] - '0');
+        isRelease = rev[6] == 0;
+    }
+    else
+        isRelease = rev[4] == 0;
+
+    info->flags = 0 /* master branch */ | (((isRelease) ? 1 : 0) << 1) /* is release */;
+
+    arm11SvcTable[0x2E] = 0xFFF00000 + freeK11Space - pos; //stubbed svc
+    freeK11Space += svcGetCFWInfo_size;
+}
+
 void patchTitleInstallMinVersionCheck(u8 *pos, u32 size)
 {
     const u8 pattern[] = {0x0A, 0x81, 0x42, 0x02};

source/patches.h

@@ -42,5 +42,6 @@ void patchFirmlaunches(u8 *pos, u32 size, u32 process9MemAddr);
 void patchFirmWrites(u8 *pos, u32 size);
 void patchFirmWriteSafe(u8 *pos, u32 size);
 void reimplementSvcBackdoor(u8 *pos, u32 size);
+void implementSvcGetCFWInfo(u8 *pos, u32 size);
 void applyLegacyFirmPatches(u8 *pos, FirmwareType firmType);
 u32 getLoader(u8 *pos, u32 *loaderSize);

source/pin.c

@@ -131,12 +131,11 @@ void verifyPin(PINData *in)
         }
         while(!(pressed & PIN_BUTTONS));
 
-        pressed &= PIN_BUTTONS & ~BUTTON_START;
-
-        if(!pressed) continue;
-
         if(pressed & BUTTON_START) mcuPowerOff();
 
+        pressed &= PIN_BUTTONS & ~BUTTON_START;
+        if(!pressed) continue;
+
         char key = PINKeyToLetter(pressed);
         enteredPassword[cnt++] = (u8)key; // add character to password.