Tegra: PMC: lock SCRATCH22 register

The PMC Scratch22 register contains the CPU reset vector to
be used by the warmboot code to power up the CPU while resuming
from  system suspend. This patch locks this PMC register to avoid
any further writes.
Signed-off-by: Varun Wadekar <vwadekar@nvidia.com>

plat/nvidia/tegra/common/drivers/pmc/pmc.c

@@ -105,6 +105,11 @@ void tegra_pmc_lock_cpu_vectors(void)
 {
 	uint32_t val;
 
+	/* lock PMC_SECURE_SCRATCH22 */
+	val = tegra_pmc_read_32(PMC_SECURE_DISABLE2);
+	val |= PMC_SECURE_DISABLE2_WRITE22_ON;
+	tegra_pmc_write_32(PMC_SECURE_DISABLE2, val);
+
 	/* lock PMC_SECURE_SCRATCH34/35 */
 	val = tegra_pmc_read_32(PMC_SECURE_DISABLE3);
 	val |= (PMC_SECURE_DISABLE3_WRITE34_ON |