tegra framebuffer - dsi one shot support

DSI one shot support requires register access in the tegra framebuffer to
poke the frame trigger bit (with both the trigger bit and the tearing effect
signal are high, a frame of pixels will be sent to the panel). The boot args
must also be expanded to have a "use tearing effect" flag.

Change-Id: Id0c3960cac5b59dd23fd6547f1b7dae4d422ac32
Reviewed-on: http://git-master/r/1460
Reviewed-by: Gary King <gking@nvidia.com>
Tested-by: Arthur Spence <aspence@nvidia.com>

2 files changed, 25 insertions, 7 deletions

diff --git a/arch/arm/mach-tegra/include/nvbootargs.h b/arch/arm/mach-tegra/include/nvbootargs.h
index 908c26f0ea52..2e11843a9a68 100644
--- a/arch/arm/mach-tegra/include/nvbootargs.h
+++ b/arch/arm/mach-tegra/include/nvbootargs.h
@@ -94,6 +94,7 @@ typedef struct NvBootArgsCarveoutRec
  */
 typedef struct NvBootArgsWarmbootRec
 {
+    /* The key used for accessing the preserved memory handle */
     NvU32 MemHandleKey;
 } NvBootArgsWarmboot;
 
@@ -112,7 +113,6 @@ typedef struct NvBootArgsPreservedMemHandleRec
     NvU32   Size;
 } NvBootArgsPreservedMemHandle;
 
-
 /**
  * Display boot args, indexed by NvBootArgKey_Display.
  *
@@ -162,6 +162,16 @@ typedef struct NvBootArgsFramebufferRec
      *  assumed to begin at Pitch * Height bytes from the
      *  previous surface.  */
     NvU8  NumSurfaces;
+    /* Flags for future expandability.
+     * Current allowable flags are:
+     * zero - default
+     * NV_BOOT_ARGS_FB_FLAG_TEARING_EFFECT - use a tearing effect signal in
+     *      combination with a trigger from the display software to generate
+     *      a frame of pixels for the display device.
+     */
+    NvU32 Flags;
+#define NVBOOTARG_FB_FLAG_TEARING_EFFECT (0x1)
+
 } NvBootArgsFramebuffer;
 
 /**
@@ -210,8 +220,8 @@ typedef struct NvBootArgsChipShmooPhysRec
     NvU32 Size;
 } NvBootArgsChipShmooPhys;
 
-#define NVBOOTARG_NUM_PRESERVED_HANDLES (NvBootArgKey_PreservedMemHandle_Num - \
-                                         NvBootArgKey_PreservedMemHandle_0)
+#define NVBOOTARG_NUM_PRESERVED_HANDLES \
+    (NvBootArgKey_PreservedMemHandle_Num - NvBootArgKey_PreservedMemHandle_0)
 
 /**
  * OS-agnostic bootarg structure.
diff --git a/arch/arm/mach-tegra/nvos/nvos.c b/arch/arm/mach-tegra/nvos/nvos.c
index 9b4329b97dc4..4de8cd4be33f 100644
--- a/arch/arm/mach-tegra/nvos/nvos.c
+++ b/arch/arm/mach-tegra/nvos/nvos.c
@@ -1445,8 +1445,7 @@ NvError NvOsBootArgGet(NvU32 key, void *arg, NvU32 size)
     }
     else
     {
-        switch (key)
-        {
+        switch (key) {
         case NvBootArgKey_ChipShmoo:
             src = &s_BootArgs.ChipShmooArgs;
             size_src = sizeof(NvBootArgsChipShmoo);
@@ -1478,10 +1477,19 @@ NvError NvOsBootArgGet(NvU32 key, void *arg, NvU32 size)
         }
     }
 
-    if (!arg || !src || (size_src!=size))
+    if( !arg || !src )
+    {
         return NvError_BadParameter;
+    }
 
-    NvOsMemcpy(arg, src, size_src);
+    /* don't copy too much if the size has changed (gotten bigger in new
+     * binaries.
+     */
+    NvOsMemcpy(arg, src, NV_MIN( size, size_src) );
+    if( size > size_src )
+    {
+        NvOsMemset( (NvU8 *)src + size_src, 0, size - size_src );
+    }
     return NvSuccess;
 }