[S] Change in libgfxinit[master]: gma: add a Turn_Off procedure to clear the graphic configuration

[Jérémy Compostella (Code Review)]

Jérémy Compostella has uploaded this change for review. ( https://review.coreboot.org/c/libgfxinit/+/69938 )

Change subject: gma: add a Turn_Off procedure to clear the graphic configuration
......................................................................

gma: add a Turn_Off procedure to clear the graphic configuration

It turns out that the FSP GOP graphic driver does not expect to face
any previously setup graphic initialization. For some configuration it
may be suitable to run the FSP GOP driver during romstage even if
libgfxinit has been used in romstage.

This new procedure offers coreboot a way to clear the graphic
configuration if needed.

Signed-off-by: Jeremy Compostella 
Change-Id: Ida65bf3303d4dbf956d6fc9340f935e6c4e6b447
---
M common/hw-gfx-gma.adb
M common/hw-gfx-gma.ads
2 files changed, 33 insertions(+), 0 deletions(-)

git pull ssh://review.coreboot.org:29418/libgfxinit refs/changes/38/69938/1

diff --git a/common/hw-gfx-gma.adb b/common/hw-gfx-gma.adb
index 146b53b..60ebeb1 100644
--- a/common/hw-gfx-gma.adb
+++ b/common/hw-gfx-gma.adb
@@ -622,6 +622,19 @@

end Initialize;

+   procedure Turn_Off
+   is
+   begin
+      Debug.Put_Line("J2M: Turning off");
+      Power_And_Clocks.Pre_All_Off;
+      Connectors.Pre_All_Off;
+      Display_Controller.All_Off;
+      Connectors.Post_All_Off;
+      PLLs.All_Off;
+      Power_And_Clocks.Post_All_Off;
+      Registers.Clear_Fences;
+   end Turn_Off;
+
    function Is_Initialized return Boolean
    with
       Refined_Post => Is_Initialized'Result = Initialized
diff --git a/common/hw-gfx-gma.ads b/common/hw-gfx-gma.ads
index 1c589d0..470fa9f 100644
--- a/common/hw-gfx-gma.ads
+++ b/common/hw-gfx-gma.ads
@@ -142,6 +142,8 @@
       Global => (Input => Init_State);
    pragma Warnings (GNATprove, On, "unused variable ""Write_Delay""");

+   procedure Turn_Off;
+
    procedure Power_Up_VGA
    with
       Global =>