Tegra186: read activity monitor's clock counter values

This patch adds a new SMC function ID to read the refclk and coreclk
clock counter values from the Activity Monitor. The non-secure world
requires this information to calculate the CPU's frequency.

Formula: "freq = (delta_coreclk / delta_refclk) * refclk_freq"

The following CPU registers have to be set by the non-secure driver
before issuing the SMC:

X1 = MPIDR of the target core
X2 = MIDR of the target core

Change-Id: I296d835def1f5788c17640c0c456b8f8f0e90824
Signed-off-by: Varun Wadekar <vwadekar@nvidia.com>
diff --git a/plat/nvidia/tegra/soc/t186/plat_setup.c b/plat/nvidia/tegra/soc/t186/plat_setup.c
index e848eab..c401b85 100644
--- a/plat/nvidia/tegra/soc/t186/plat_setup.c
+++ b/plat/nvidia/tegra/soc/t186/plat_setup.c
@@ -102,6 +102,8 @@
 			MT_DEVICE | MT_RW | MT_SECURE),
 	MAP_REGION_FLAT(TEGRA_MMCRAB_BASE, 0x60000, /* 384KB */
 			MT_DEVICE | MT_RW | MT_SECURE),
+	MAP_REGION_FLAT(TEGRA_ARM_ACTMON_CTR_BASE, 0x20000, /* 128KB - ARM/Denver */
+			MT_DEVICE | MT_RW | MT_SECURE),
 	MAP_REGION_FLAT(TEGRA_SMMU_BASE, 0x1000000, /* 64KB */
 			MT_DEVICE | MT_RW | MT_SECURE),
 	{0}