[FREELDR] Xbox memory management improvements (#1961)

- Reuse the framebuffer address that was set up by the firmware.
- Get rid of XboxMemReserveMemory() and use ReserveMemory() instead.

CORE-16216

boot/freeldr/freeldr/arch/i386/xboxmem.c

@@ -26,6 +26,8 @@ DBG_DEFAULT_CHANNEL(MEMORY);
 
 static ULONG InstalledMemoryMb = 0;
 static ULONG AvailableMemoryMb = 0;
+extern PVOID FrameBuffer;
+extern ULONG FrameBufferSize;
 
 #define TEST_SIZE     0x200
 #define TEST_PATTERN1 0xAA
@@ -38,6 +40,14 @@ SetMemory(
     SIZE_T Size,
     TYPE_OF_MEMORY MemoryType);
 
+extern VOID
+ReserveMemory(
+    PFREELDR_MEMORY_DESCRIPTOR MemoryMap,
+    ULONG_PTR BaseAddress,
+    SIZE_T Size,
+    TYPE_OF_MEMORY MemoryType,
+    PCHAR Usage);
+
 extern ULONG
 PcMemFinalizeMemoryMap(
     PFREELDR_MEMORY_DESCRIPTOR MemoryMap);
@@ -85,7 +95,6 @@ XboxMemInit(VOID)
     WRITE_PORT_ULONG((ULONG*) 0xcf8, CONFIG_CMD(0, 0, 0x84));
     WRITE_PORT_ULONG((ULONG*) 0xcfc, InstalledMemoryMb * 1024 * 1024 - 1);
 
-    /* 4 MB video framebuffer is reserved later using XboxMemReserveMemory() */
     AvailableMemoryMb = InstalledMemoryMb;
 }
 
@@ -105,37 +114,18 @@ XboxMemGetMemoryMap(ULONG *MemoryMapSize)
               AvailableMemoryMb * 1024 * 1024,
               LoaderFree);
 
-    /* Video memory */
-    SetMemory(XboxMemoryMap,
-              AvailableMemoryMb * 1024 * 1024,
-              (InstalledMemoryMb - AvailableMemoryMb) * 1024 * 1024,
-              LoaderFirmwarePermanent);
+    if (FrameBufferSize != 0)
+    {
+        /* Video memory */
+        ReserveMemory(XboxMemoryMap,
+                      (ULONG_PTR)FrameBuffer,
+                      FrameBufferSize,
+                      LoaderFirmwarePermanent,
+                      "Video memory");
+    }
 
     *MemoryMapSize = PcMemFinalizeMemoryMap(XboxMemoryMap);
     return XboxMemoryMap;
 }
 
-PVOID
-XboxMemReserveMemory(ULONG MbToReserve)
-{
-    /* This function is used to reserve video framebuffer in XboxVideoInit() */
-
-    if (InstalledMemoryMb == 0)
-    {
-        /* Hmm, seems we're not initialized yet */
-        XboxMemInit();
-    }
-
-    if (MbToReserve > AvailableMemoryMb)
-    {
-        /* Can't satisfy the request */
-        return NULL;
-    }
-
-    AvailableMemoryMb -= MbToReserve;
-
-    /* Top of available memory points to the space just reserved */
-    return (PVOID)(AvailableMemoryMb * 1024 * 1024);
-}
-
 /* EOF */

boot/freeldr/freeldr/arch/i386/xboxvideo.c

@@ -24,7 +24,8 @@
 
 DBG_DEFAULT_CHANNEL(UI);
 
-static PVOID FrameBuffer;
+PVOID FrameBuffer;
+ULONG FrameBufferSize;
 static ULONG ScreenWidth;
 static ULONG ScreenHeight;
 static ULONG BytesPerPixel;
@@ -126,8 +127,15 @@ XboxVideoInit(VOID)
 {
   ULONG AvMode;
 
-  FrameBuffer = (PVOID)((ULONG) XboxMemReserveMemory(FB_SIZE_MB) | 0xf0000000);
+  /* Reuse framebuffer that was set up by firmware */
+  FrameBuffer = (PVOID)*((PULONG) 0xfd600800);
+  /* Verify that framebuffer address is page-aligned */
+  ASSERT((ULONG_PTR)FrameBuffer % PAGE_SIZE == 0);
 
+  /* FIXME: obtain fb size from firmware somehow (Cromwell reserves high 4 MB of RAM) */
+  FrameBufferSize = 4 * 1024 * 1024;
+
+  /* FIXME: don't use SMBus, obtain current video resolution directly from NV2A */
   if (I2CTransmitByteGetReturn(0x10, 0x04, &AvMode))
     {
       if (1 == AvMode) /* HDTV */
@@ -157,9 +165,6 @@ XboxVideoInit(VOID)
   Delta = (ScreenWidth * BytesPerPixel + 3) & ~ 0x3;
 
   XboxVideoClearScreenColor(MAKE_COLOR(0, 0, 0), TRUE);
-
-  /* Tell the nVidia controller about the framebuffer */
-  *((PULONG) 0xfd600800) = (ULONG) FrameBuffer;
 }
 
 VIDEODISPLAYMODE

boot/freeldr/freeldr/include/arch/i386/machxbox.h

@@ -63,7 +63,6 @@ VOID XboxVideoPrepareForReactOS(VOID);
 VOID XboxPrepareForReactOS(VOID);
 
 VOID XboxMemInit(VOID);
-PVOID XboxMemReserveMemory(ULONG MbToReserve);
 PFREELDR_MEMORY_DESCRIPTOR XboxMemGetMemoryMap(ULONG *MemoryMapSize);
 
 BOOLEAN XboxDiskReadLogicalSectors(UCHAR DriveNumber, ULONGLONG SectorNumber, ULONG SectorCount, PVOID Buffer);