drm/amdgpu/discovery: reserve discovery data at the top of VRAM

IP Discovery data is TMR fenced by the latest PSP BL,
so we need to reserve this region.

Tested on navi10/12/14 with VBIOS integrated with latest PSP BL.

v2: use DISCOVERY_TMR_SIZE macro as bo size
    use amdgpu_bo_create_kernel_at() to allocate bo
Signed-off-by: Xiaojie Yuan <xiaojie.yuan@amd.com>
Reviewed-by: Hawking Zhang <Hawking.Zhang@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/amdgpu/amdgpu.h

@@ -759,6 +759,7 @@ struct amdgpu_device {
 	uint8_t				*bios;
 	uint32_t			bios_size;
 	struct amdgpu_bo		*stolen_vga_memory;
+	struct amdgpu_bo		*discovery_memory;
 	uint32_t			bios_scratch_reg_offset;
 	uint32_t			bios_scratch[AMDGPU_BIOS_NUM_SCRATCH];
 

drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c

@@ -136,7 +136,7 @@ static int amdgpu_discovery_read_binary(struct amdgpu_device *adev, uint8_t *bin
 {
 	uint32_t *p = (uint32_t *)binary;
 	uint64_t vram_size = (uint64_t)RREG32(mmRCC_CONFIG_MEMSIZE) << 20;
-	uint64_t pos = vram_size - BINARY_MAX_SIZE;
+	uint64_t pos = vram_size - DISCOVERY_TMR_SIZE;
 	unsigned long flags;
 
 	while (pos < vram_size) {
@@ -179,7 +179,7 @@ int amdgpu_discovery_init(struct amdgpu_device *adev)
 	uint16_t checksum;
 	int r;
 
-	adev->discovery = kzalloc(BINARY_MAX_SIZE, GFP_KERNEL);
+	adev->discovery = kzalloc(DISCOVERY_TMR_SIZE, GFP_KERNEL);
 	if (!adev->discovery)
 		return -ENOMEM;
 

drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.h

@@ -24,6 +24,8 @@
 #ifndef __AMDGPU_DISCOVERY__
 #define __AMDGPU_DISCOVERY__
 
+#define DISCOVERY_TMR_SIZE  (64 << 10)
+
 int amdgpu_discovery_init(struct amdgpu_device *adev);
 void amdgpu_discovery_fini(struct amdgpu_device *adev);
 int amdgpu_discovery_reg_base_init(struct amdgpu_device *adev);

drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c

@@ -1750,6 +1750,20 @@ int amdgpu_ttm_init(struct amdgpu_device *adev)
 				    NULL, &stolen_vga_buf);
 	if (r)
 		return r;
+
+	/*
+	 * reserve one TMR (64K) memory at the top of VRAM which holds
+	 * IP Discovery data and is protected by PSP.
+	 */
+	r = amdgpu_bo_create_kernel_at(adev,
+				       adev->gmc.real_vram_size - DISCOVERY_TMR_SIZE,
+				       DISCOVERY_TMR_SIZE,
+				       AMDGPU_GEM_DOMAIN_VRAM,
+				       &adev->discovery_memory,
+				       NULL);
+	if (r)
+		return r;
+
 	DRM_INFO("amdgpu: %uM of VRAM memory ready\n",
 		 (unsigned) (adev->gmc.real_vram_size / (1024 * 1024)));
 
@@ -1814,6 +1828,9 @@ void amdgpu_ttm_late_init(struct amdgpu_device *adev)
 	void *stolen_vga_buf;
 	/* return the VGA stolen memory (if any) back to VRAM */
 	amdgpu_bo_free_kernel(&adev->stolen_vga_memory, NULL, &stolen_vga_buf);
+
+	/* return the IP Discovery TMR memory back to VRAM */
+	amdgpu_bo_free_kernel(&adev->discovery_memory, NULL, NULL);
 }
 
 /**

drivers/gpu/drm/amd/include/discovery.h

@@ -25,7 +25,6 @@
 #define _DISCOVERY_H_
 
 #define PSP_HEADER_SIZE                 256
-#define BINARY_MAX_SIZE                 (64 << 10)
 #define BINARY_SIGNATURE                0x28211407
 #define DISCOVERY_TABLE_SIGNATURE       0x53445049