Reserve a Video Memory aperture in DRAM memory

This patch adds support to reserve a memory carveout region in the
DRAM on Tegra SoCs. The memory controller provides specific registers
to specify the aperture's base and size. This aperture can also be
changed dynamically in order to re-size the memory available for
DRM video playback. In case of the new aperture not overlapping
the previous one, the previous aperture has to be cleared before
setting up the new one. This means we do not "leak" any video data
to the NS world.

Signed-off-by: Varun Wadekar <vwadekar@nvidia.com>
diff --git a/plat/nvidia/tegra/include/drivers/memctrl.h b/plat/nvidia/tegra/include/drivers/memctrl.h
index 867f09e..26c8057 100644
--- a/plat/nvidia/tegra/include/drivers/memctrl.h
+++ b/plat/nvidia/tegra/include/drivers/memctrl.h
@@ -64,6 +64,10 @@
 #define MC_SECURITY_CFG0_0			0x70
 #define MC_SECURITY_CFG1_0			0x74
 
+/* Video Memory carveout configuration registers */
+#define MC_VIDEO_PROTECT_BASE			0x648
+#define MC_VIDEO_PROTECT_SIZE_MB		0x64c
+
 static inline uint32_t tegra_mc_read_32(uint32_t off)
 {
 	return mmio_read_32(TEGRA_MC_BASE + off);
@@ -76,5 +80,6 @@
 
 void tegra_memctrl_setup(void);
 void tegra_memctrl_tzdram_setup(uint64_t phys_base, uint32_t size_in_bytes);
+void tegra_memctrl_videomem_setup(uint64_t phys_base, uint32_t size_in_bytes);
 
 #endif /* __MEMCTRL_H__ */