[coreboot-gerrit] Change in libgfxinit[master]: gma bxt panel: Correct panel backlight handling

[Nico Huber (Code Review)]

Nico Huber has submitted this change. ( https://review.coreboot.org/c/libgfxinit/+/38265 )

Change subject: gma bxt panel: Correct panel backlight handling
......................................................................

gma bxt panel: Correct panel backlight handling

Change-Id: Icfad261fb4d5ff478974948c0148880c5b8cb40c
Signed-off-by: Nico Huber 
Reviewed-on: https://review.coreboot.org/c/libgfxinit/+/38265
Tested-by: Nico Huber 
Reviewed-by: Angel Pons 
---
M common/hw-gfx-gma-config.ads.template
M common/hw-gfx-gma-panel.adb
M common/hw-gfx-gma-panel.ads
3 files changed, 40 insertions(+), 19 deletions(-)

Approvals:
  Nico Huber: Verified
  Angel Pons: Looks good to me, approved

diff --git a/common/hw-gfx-gma-config.ads.template b/common/hw-gfx-gma-config.ads.template
index 01a67c1..39fa825 100644
--- a/common/hw-gfx-gma-config.ads.template
+++ b/common/hw-gfx-gma-config.ads.template
@@ -182,6 +182,7 @@
    Use_PP_VDD_Override           : <genbool> := Up_To_Ironlake;
    Has_PCH_Panel_Power           : <genbool> := Ironlake_On;
    Has_PP_Divisor_Reg            : <genbool> := not Gen_Broxton;
+   Has_New_Backlight_Control     : <genbool> := Gen_Broxton;

----------- PCH/FDI: ---------
    Has_PCH                       : <genbool> := not Gen_Broxton and not Gen_G45;
diff --git a/common/hw-gfx-gma-panel.adb b/common/hw-gfx-gma-panel.adb
index 1cd0d55..3d6b342 100644
--- a/common/hw-gfx-gma-panel.adb
+++ b/common/hw-gfx-gma-panel.adb
@@ -155,8 +155,11 @@
    PCH_BLC_PWM_CTL1_PHASE_IN_INCREMENT : constant := 16#00_00ff# * 2 **  0;

PCH_BLC_PWM_CTL2_BL_MOD_FREQ_MASK   : constant := 16#00_ffff# * 2 ** 16;
+   PCH_BLC_PWM_CTL2_BL_MOD_FREQ_SHIFT  : constant :=                    16;
    PCH_BLC_PWM_CTL2_BL_DUTY_CYC_MASK   : constant := 16#00_ffff# * 2 **  0;

+   BXT_BLC_PWM_CTL_ENABLE              : constant := 16#00_0001# * 2 ** 31;
+
    ----------------------------------------------------------------------------

procedure Static_Init
@@ -380,9 +383,15 @@

pragma Debug (Debug.Put_Line (GNAT.Source_Info.Enclosing_Entity));

-      Registers.Set_Mask
-         (Register   => Panel_PP_Regs.CONTROL,
-          Mask       => PCH_PP_CONTROL_BACKLIGHT_ENABLE);
+      if Config.Has_New_Backlight_Control then
+         Registers.Set_Mask
+           (Register => Registers.BXT_BLC_PWM_CTL_1,
+            Mask     => BXT_BLC_PWM_CTL_ENABLE);
+      else
+         Registers.Set_Mask
+           (Register => Panel_PP_Regs.CONTROL,
+            Mask     => PCH_PP_CONTROL_BACKLIGHT_ENABLE);
+      end if;
    end Backlight_On;

procedure Backlight_Off (Panel : Panel_Control) is
@@ -393,12 +402,18 @@

pragma Debug (Debug.Put_Line (GNAT.Source_Info.Enclosing_Entity));

-      Registers.Unset_Mask
-        (Register   => Panel_PP_Regs.CONTROL,
-         Mask       => PCH_PP_CONTROL_BACKLIGHT_ENABLE);
+      if Config.Has_New_Backlight_Control then
+         Registers.Unset_Mask
+           (Register => Registers.BXT_BLC_PWM_CTL_1,
+            Mask     => BXT_BLC_PWM_CTL_ENABLE);
+      else
+         Registers.Unset_Mask
+           (Register => Panel_PP_Regs.CONTROL,
+            Mask     => PCH_PP_CONTROL_BACKLIGHT_ENABLE);
+      end if;
    end Backlight_Off;

-   procedure Set_Backlight (Panel : Panel_Control; Level : Word16) is
+   procedure Set_Backlight (Panel : Panel_Control; Level : Word32) is
    begin
       if Panel not in Valid_Panels then
          return;
@@ -406,15 +421,17 @@

pragma Debug (Debug.Put_Line (GNAT.Source_Info.Enclosing_Entity));

-      Registers.Unset_And_Set_Mask
-        (Register    => Registers.BLC_PWM_CPU_CTL,
-         Mask_Unset  => CPU_BLC_PWM_DATA_BL_DUTY_CYC_MASK,
-         Mask_Set    => Word32 (Level));
+      if Config.Has_New_Backlight_Control then
+         Registers.Write (Registers.BXT_BLC_PWM_DUTY_1, Level);
+      else
+         Registers.Unset_And_Set_Mask
+           (Register    => Registers.BLC_PWM_CPU_CTL,
+            Mask_Unset  => CPU_BLC_PWM_DATA_BL_DUTY_CYC_MASK,
+            Mask_Set    => Level);
+      end if;
    end Set_Backlight;

-   procedure Get_Max_Backlight (Panel : Panel_Control; Level : out Word16)
-   is
-      Reg : Word32;
+   procedure Get_Max_Backlight (Panel : Panel_Control; Level : out Word32) is
    begin
       if Panel not in Valid_Panels then
          Level := 0;
@@ -423,9 +440,12 @@

pragma Debug (Debug.Put_Line (GNAT.Source_Info.Enclosing_Entity));

-      Registers.Read (Registers.BLC_PWM_PCH_CTL2, Reg);
-      Level := Word16
-        (Shift_Right (Reg and PCH_BLC_PWM_CTL2_BL_MOD_FREQ_MASK, 16));
+      if Config.Has_New_Backlight_Control then
+         Registers.Read (Registers.BXT_BLC_PWM_FREQ_1, Level);
+      else
+         Registers.Read (Registers.BLC_PWM_PCH_CTL2, Level);
+         Level := Shift_Right (Level, PCH_BLC_PWM_CTL2_BL_MOD_FREQ_SHIFT);
+      end if;
    end Get_Max_Backlight;

end HW.GFX.GMA.Panel;
diff --git a/common/hw-gfx-gma-panel.ads b/common/hw-gfx-gma-panel.ads
index baf47f7..2a97f0e 100644
--- a/common/hw-gfx-gma-panel.ads
+++ b/common/hw-gfx-gma-panel.ads
@@ -54,8 +54,8 @@

procedure Backlight_Off (Panel : Panel_Control);

-   procedure Set_Backlight (Panel : Panel_Control; Level : Word16);
+   procedure Set_Backlight (Panel : Panel_Control; Level : Word32);

-   procedure Get_Max_Backlight (Panel : Panel_Control; Level : out Word16);
+   procedure Get_Max_Backlight (Panel : Panel_Control; Level : out Word32);

end HW.GFX.GMA.Panel;