Tegra194: support for boot params wider than 32-bits

The previous bootloader is not able to pass boot params wider than
32-bits due to an oversight in the scratch register being used. A
new secure scratch register #75 has been assigned to pass the higher
bits.

This patch adds support to parse the higher bits from scratch #75
and use them in calculating the base address for the location of
the boot params.

Scratch #75 format
====================
31:16 - bl31_plat_params high address
15:0 - bl31_params high address

Change-Id: Id53c45f70a9cb370c776ed7c82ad3f2258576a80
Signed-off-by: Steven Kao <skao@nvidia.com>
diff --git a/plat/nvidia/tegra/include/t194/tegra_def.h b/plat/nvidia/tegra/include/t194/tegra_def.h
index da8056b..6eb58b9 100644
--- a/plat/nvidia/tegra/include/t194/tegra_def.h
+++ b/plat/nvidia/tegra/include/t194/tegra_def.h
@@ -180,6 +180,7 @@
  * Tegra scratch registers constants
  ******************************************************************************/
 #define TEGRA_SCRATCH_BASE		U(0x0C390000)
+#define  SECURE_SCRATCH_RSV75   	U(0x2BC)
 #define  SECURE_SCRATCH_RSV81_LO	U(0x2EC)
 #define  SECURE_SCRATCH_RSV81_HI	U(0x2F0)
 #define  SECURE_SCRATCH_RSV97		U(0x36C)
@@ -188,8 +189,14 @@
 #define  SECURE_SCRATCH_RSV109_LO	U(0x3CC)
 #define  SECURE_SCRATCH_RSV109_HI	U(0x3D0)
 
-#define SCRATCH_BL31_PARAMS_ADDR	SECURE_SCRATCH_RSV81_LO
-#define SCRATCH_BL31_PLAT_PARAMS_ADDR	SECURE_SCRATCH_RSV81_HI
+#define SCRATCH_BL31_PARAMS_HI_ADDR	SECURE_SCRATCH_RSV75
+#define  SCRATCH_BL31_PARAMS_HI_ADDR_MASK  U(0xFFFF)
+#define  SCRATCH_BL31_PARAMS_HI_ADDR_SHIFT U(0)
+#define SCRATCH_BL31_PARAMS_LO_ADDR	SECURE_SCRATCH_RSV81_LO
+#define SCRATCH_BL31_PLAT_PARAMS_HI_ADDR SECURE_SCRATCH_RSV75
+#define  SCRATCH_BL31_PLAT_PARAMS_HI_ADDR_MASK  U(0xFFFF0000)
+#define  SCRATCH_BL31_PLAT_PARAMS_HI_ADDR_SHIFT U(16)
+#define SCRATCH_BL31_PLAT_PARAMS_LO_ADDR SECURE_SCRATCH_RSV81_HI
 #define SCRATCH_SECURE_BOOTP_FCFG	SECURE_SCRATCH_RSV97
 #define SCRATCH_SMMU_TABLE_ADDR_LO	SECURE_SCRATCH_RSV99_LO
 #define SCRATCH_SMMU_TABLE_ADDR_HI	SECURE_SCRATCH_RSV99_HI