drm/amdgpu: Add NPS switch support for GC 9.4.3

Add dynamic NPS switch support for GC 9.4.3 variants. Only GC v9.4.3 and
GC v9.4.4 currently support this. NPS switch is only supported if an SOC
supports multiple NPS modes.

Signed-off-by: Lijo Lazar <[e-mail]>
Signed-off-by: Rajneesh Bhardwaj <[e-mail]>
Reviewed-by: Feifei Xu <[e-mail]>
Reviewed-by: Hawking Zhang <[e-mail]>
Signed-off-by: Alex Deucher <[e-mail]>

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

···
 	int (*get_compute_partition_mode)(struct amdgpu_device *adev);
 	u32 (*get_memory_partition_mode)(struct amdgpu_device *adev,
 					 u32 *supp_modes);
+	bool (*is_nps_switch_requested)(struct amdgpu_device *adev);
 	u64 (*get_pcie_replay_count)(struct amdgpu_device *adev);
 	void (*set_reg_remap)(struct amdgpu_device *adev);
 };

drivers/gpu/drm/amd/amdgpu/gmc_v9_0.c

···
 	return gmc_v9_0_get_memory_partition(adev, NULL);
 }
 
+static bool gmc_v9_0_need_reset_on_init(struct amdgpu_device *adev)
+{
+	if (adev->nbio.funcs && adev->nbio.funcs->is_nps_switch_requested &&
+	    adev->nbio.funcs->is_nps_switch_requested(adev)) {
+		adev->gmc.reset_flags |= AMDGPU_GMC_INIT_RESET_NPS;
+		return true;
+	}
+
+	return false;
+}
+
 static const struct amdgpu_gmc_funcs gmc_v9_0_gmc_funcs = {
 	.flush_gpu_tlb = gmc_v9_0_flush_gpu_tlb,
 	.flush_gpu_tlb_pasid = gmc_v9_0_flush_gpu_tlb_pasid,
···
 	.override_vm_pte_flags = gmc_v9_0_override_vm_pte_flags,
 	.get_vbios_fb_size = gmc_v9_0_get_vbios_fb_size,
 	.query_mem_partition_mode = &gmc_v9_0_query_memory_partition,
+	.request_mem_partition_mode = &amdgpu_gmc_request_memory_partition,
+	.need_reset_on_init = &gmc_v9_0_need_reset_on_init,
 };
 
 static void gmc_v9_0_set_gmc_funcs(struct amdgpu_device *adev)
···
 {
 	if (!adev->gmc.xgmi.connected_to_cpu)
 		adev->gmc.xgmi.ras = &xgmi_ras;
+}
+
+static void gmc_v9_0_init_nps_details(struct amdgpu_device *adev)
+{
+	adev->gmc.supported_nps_modes = 0;
+
+	if (amdgpu_sriov_vf(adev) || (adev->flags & AMD_IS_APU))
+		return;
+
+	/*TODO: Check PSP version also which supports NPS switch. Otherwise keep
+	 * supported modes as 0.
+	 */
+	switch (amdgpu_ip_version(adev, GC_HWIP, 0)) {
+	case IP_VERSION(9, 4, 3):
+	case IP_VERSION(9, 4, 4):
+		adev->gmc.supported_nps_modes =
+			BIT(AMDGPU_NPS1_PARTITION_MODE) |
+			BIT(AMDGPU_NPS4_PARTITION_MODE);
+		break;
+	default:
+		break;
+	}
 }
 
 static int gmc_v9_0_early_init(struct amdgpu_ip_block *ip_block)
···
 	if (r)
 		return r;
 
+	gmc_v9_0_init_nps_details(adev);
 	/*
 	 * number of VMs
 	 * VMID 0 is reserved for System
···
 
 static int gmc_v9_0_resume(struct amdgpu_ip_block *ip_block)
 {
+	struct amdgpu_device *adev = ip_block->adev;
 	int r;
+
+	/* If a reset is done for NPS mode switch, read the memory range
+	 * information again.
+	 */
+	if (adev->gmc.reset_flags & AMDGPU_GMC_INIT_RESET_NPS) {
+		gmc_v9_0_init_sw_mem_ranges(adev, adev->gmc.mem_partitions);
+		adev->gmc.reset_flags &= ~AMDGPU_GMC_INIT_RESET_NPS;
+	}
 
 	r = gmc_v9_0_hw_init(ip_block);
 	if (r)

drivers/gpu/drm/amd/amdgpu/nbio_v7_9.c

···
 	return px;
 }
 
+static bool nbio_v7_9_is_nps_switch_requested(struct amdgpu_device *adev)
+{
+	u32 tmp;
+
+	tmp = RREG32_SOC15(NBIO, 0, regBIF_BX_PF0_PARTITION_MEM_STATUS);
+	tmp = REG_GET_FIELD(tmp, BIF_BX_PF0_PARTITION_MEM_STATUS,
+			    CHANGE_STATUE);
+
+	/* 0x8 - NPS switch requested */
+	return (tmp == 0x8);
+}
 static u32 nbio_v7_9_get_memory_partition_mode(struct amdgpu_device *adev,
 					       u32 *supp_modes)
 {
···
 	.remap_hdp_registers = nbio_v7_9_remap_hdp_registers,
 	.get_compute_partition_mode = nbio_v7_9_get_compute_partition_mode,
 	.get_memory_partition_mode = nbio_v7_9_get_memory_partition_mode,
+	.is_nps_switch_requested = nbio_v7_9_is_nps_switch_requested,
 	.init_registers = nbio_v7_9_init_registers,
 	.get_pcie_replay_count = nbio_v7_9_get_pcie_replay_count,
 	.set_reg_remap = nbio_v7_9_set_reg_remap,