Tegra: SiP: set GPU in reset after vpr resize

Whenever the VPR memory is resized, the GPU is put into reset first
and then the new VPR parameters are programmed to the memory controller
block. There exists a scenario, where the GPU might be out before we
program the new VPR parameters. This means, the GPU would still be
using older settings and leak secrets.

This patch puts the GPU back into reset, if it is out of reset after
resizing VPR, to mitigate this hole.

Change-Id: I38a1000e3803f80909efcb02e27da4bd46909931
Signed-off-by: Jeetesh Burman <jburman@nvidia.com>

plat/nvidia/tegra/common/tegra_sip_calls.c

@@ -116,6 +116,16 @@ uintptr_t tegra_sip_handler(uint32_t smc_fid,
 			/* new video memory carveout settings */
 			tegra_memctrl_videomem_setup(x1, local_x2_32);
 
+			/*
+			 * Ensure again that GPU is still in reset after VPR resize
+			 */
+			regval = mmio_read_32(TEGRA_CAR_RESET_BASE +
+					      TEGRA_GPU_RESET_REG_OFFSET);
+			if ((regval & GPU_RESET_BIT) == 0U) {
+				mmio_write_32(TEGRA_CAR_RESET_BASE + TEGRA_GPU_RESET_GPU_SET_OFFSET,
+									GPU_SET_BIT);
+			}
+
 			SMC_RET1(handle, 0);
 
 		/*

plat/nvidia/tegra/include/t132/tegra_def.h

@@ -41,7 +41,9 @@
  ******************************************************************************/
 #define TEGRA_CAR_RESET_BASE		U(0x60006000)
 #define TEGRA_GPU_RESET_REG_OFFSET	U(0x28C)
+#define TEGRA_GPU_RESET_GPU_SET_OFFSET	U(0x290)
 #define  GPU_RESET_BIT			(U(1) << 24)
+#define  GPU_SET_BIT			(U(1) << 24)
 
 /*******************************************************************************
  * Tegra Flow Controller constants

plat/nvidia/tegra/include/t186/tegra_def.h

@@ -210,7 +210,9 @@
  ******************************************************************************/
 #define TEGRA_CAR_RESET_BASE		U(0x05000000)
 #define TEGRA_GPU_RESET_REG_OFFSET	U(0x30)
+#define TEGRA_GPU_RESET_GPU_SET_OFFSET	U(0x34)
 #define  GPU_RESET_BIT			(U(1) << 0)
+#define  GPU_SET_BIT			(U(1) << 0)
 #define TEGRA_GPCDMA_RST_SET_REG_OFFSET	U(0x6A0004)
 #define TEGRA_GPCDMA_RST_CLR_REG_OFFSET	U(0x6A0008)
 

plat/nvidia/tegra/include/t210/tegra_def.h

@@ -85,7 +85,9 @@
  ******************************************************************************/
 #define TEGRA_CAR_RESET_BASE		U(0x60006000)
 #define TEGRA_GPU_RESET_REG_OFFSET	U(0x28C)
+#define TEGRA_GPU_RESET_GPU_SET_OFFSET	U(0x290)
 #define  GPU_RESET_BIT			(U(1) << 24)
+#define  GPU_SET_BIT			(U(1) << 24)
 #define TEGRA_RST_DEV_CLR_V		U(0x434)
 #define TEGRA_CLK_ENB_V			U(0x440)