gma registers: Add procedures to set fence registers
Through fence registers, we can tell the hardware which parts of the
aperture cover tiled framebuffers. Only legacy X and Y tiling is sup-
ported. According to `i915_reg.h` there are 16 fence registers from
G4x on and 32 from Ivy Bridge on (this only partially matches docu-
mentation: Haswell has 16 regs documented and the fence registers
were not documented at all before).
Change-Id: I02edc99b315e24dc175c6f93aff627e59cb1ff0b
Signed-off-by: Nico Huber <nico.huber@secunet.com>
Reviewed-on: https://review.coreboot.org/22708
Reviewed-by: Nico Huber <nico.h@gmx.de>
Tested-by: Nico Huber <nico.h@gmx.de>
diff --git a/common/hw-gfx-gma-registers.adb b/common/hw-gfx-gma-registers.adb
index 4a22564..94965d5 100644
--- a/common/hw-gfx-gma-registers.adb
+++ b/common/hw-gfx-gma-registers.adb
@@ -61,19 +61,84 @@
----------------------------------------------------------------------------
+ subtype Fence_Range is Registers_Range range 0 .. Config.Fence_Count - 1;
+
+ FENCE_PAGE_SHIFT : constant := 12;
+ FENCE_PAGE_MASK : constant := 16#ffff_f000#;
+ FENCE_TILE_WALK_YMAJOR : constant := 1 * 2 ** 1;
+ FENCE_VALID : constant := 1 * 2 ** 0;
+
+ function Fence_Lower_Idx (Fence : Fence_Range) return Registers_Range is
+ (Config.Fence_Base / Register_Width + 2 * Fence);
+ function Fence_Upper_Idx (Fence : Fence_Range) return Registers_Range is
+ (Fence_Lower_Idx (Fence) + 1);
+
procedure Clear_Fences
is
- Fence_Regs_Base : constant :=
- (case Config.CPU is
- when Ironlake => 16#00_3000#,
- when Sandybridge .. Skylake => 16#10_0000#);
- subtype Fence_Range is Registers_Range range 0 .. 63;
begin
- for Idx in Fence_Range loop
- Regs.Write (Fence_Regs_Base / Register_Width + Idx, 0);
+ for Fence in Fence_Range loop
+ Regs.Write (Fence_Lower_Idx (Fence), 0);
end loop;
end Clear_Fences;
+ procedure Add_Fence
+ (First_Page : in GTT_Range;
+ Last_Page : in GTT_Range;
+ Tiling : in XY_Tiling;
+ Pitch : in Natural;
+ Success : out Boolean)
+ is
+ Y_Tiles : constant Boolean := Tiling = Y_Tiled;
+ Reg32 : Word32;
+ begin
+ pragma Debug (Debug.Put (GNAT.Source_Info.Enclosing_Entity & ": "));
+ pragma Debug (Debug.Put_Word32 (Shift_Left (Word32 (First_Page), 12)));
+ pragma Debug (Debug.Put (":"));
+ pragma Debug (Debug.Put_Word32 (Shift_Left (Word32 (Last_Page), 12)));
+ pragma Debug (not Y_Tiles, Debug.Put (" X tiled in "));
+ pragma Debug ( Y_Tiles, Debug.Put (" Y tiled in "));
+ pragma Debug (Debug.Put_Int32 (Int32 (Pitch)));
+ pragma Debug (Debug.Put_Line (" tiles per row."));
+
+ Success := False;
+ for Fence in Fence_Range loop
+ Regs.Read (Reg32, Fence_Lower_Idx (Fence));
+ if (Reg32 and FENCE_VALID) = 0 then
+ Regs.Write
+ (Index => Fence_Lower_Idx (Fence),
+ Value => Shift_Left (Word32 (First_Page), FENCE_PAGE_SHIFT) or
+ (if Y_Tiles then FENCE_TILE_WALK_YMAJOR else 0) or
+ FENCE_VALID);
+ Regs.Write
+ (Index => Fence_Upper_Idx (Fence),
+ Value => Shift_Left (Word32 (Last_Page), FENCE_PAGE_SHIFT) or
+ Word32 (Pitch) * (if Y_Tiles then 1 else 4) - 1);
+ Success := True;
+ exit;
+ end if;
+ end loop;
+ end Add_Fence;
+
+ procedure Remove_Fence (First_Page, Last_Page : GTT_Range)
+ is
+ Page_Lower : constant Word32 :=
+ Shift_Left (Word32 (First_Page), FENCE_PAGE_SHIFT);
+ Page_Upper : constant Word32 :=
+ Shift_Left (Word32 (Last_Page), FENCE_PAGE_SHIFT);
+ Fence_Upper, Fence_Lower : Word32;
+ begin
+ for Fence in Fence_Range loop
+ Regs.Read (Fence_Lower, Fence_Lower_Idx (Fence));
+ Regs.Read (Fence_Upper, Fence_Upper_Idx (Fence));
+ if (Fence_Lower and FENCE_PAGE_MASK) = Page_Lower and
+ (Fence_Upper and FENCE_PAGE_MASK) = Page_Upper
+ then
+ Regs.Write (Fence_Lower_Idx (Fence), 0);
+ exit;
+ end if;
+ end loop;
+ end Remove_Fence;
+
----------------------------------------------------------------------------
procedure Write_GTT