drm/amdkfd: Add topology support for CPUs

Currently, the KFD topology information is generated by parsing the CRAT
(ACPI) table. However, at present CRAT table is available only for AMD
APUs. To support CPUs on systems without a CRAT table, the KFD driver will
create a Virtual CRAT (VCRAT) table and then the existing code will parse
that table to generate topology.
Signed-off-by: Harish Kasiviswanathan <Harish.Kasiviswanathan@amd.com>
Signed-off-by: Felix Kuehling <Felix.Kuehling@amd.com>
Reviewed-by: Oded Gabbay <oded.gabbay@gmail.com>
Signed-off-by: Oded Gabbay <oded.gabbay@gmail.com>

drivers/gpu/drm/amd/amdkfd/kfd_crat.h

@@ -44,6 +44,10 @@
 
 #define CRAT_OEMID_64BIT_MASK ((1ULL << (CRAT_OEMID_LENGTH * 8)) - 1)
 
+/* Compute Unit flags */
+#define COMPUTE_UNIT_CPU	(1 << 0)  /* Create Virtual CRAT for CPU */
+#define COMPUTE_UNIT_GPU	(1 << 1)  /* Create Virtual CRAT for GPU */
+
 struct crat_header {
 	uint32_t	signature;
 	uint32_t	length;
@@ -302,9 +306,14 @@ struct cdit_header {
 
 #pragma pack()
 
+struct kfd_dev;
+
 int kfd_create_crat_image_acpi(void **crat_image, size_t *size);
 void kfd_destroy_crat_image(void *crat_image);
 int kfd_parse_crat_table(void *crat_image, struct list_head *device_list,
 			 uint32_t proximity_domain);
+int kfd_create_crat_image_virtual(void **crat_image, size_t *size,
+				  int flags, struct kfd_dev *kdev,
+				  uint32_t proximity_domain);
 
 #endif /* KFD_CRAT_H_INCLUDED */

drivers/gpu/drm/amd/amdkfd/kfd_priv.h

@@ -671,6 +671,7 @@ int kfd_topology_remove_device(struct kfd_dev *gpu);
 struct kfd_dev *kfd_device_by_id(uint32_t gpu_id);
 struct kfd_dev *kfd_device_by_pci_dev(const struct pci_dev *pdev);
 int kfd_topology_enum_kfd_devices(uint8_t idx, struct kfd_dev **kdev);
+int kfd_numa_node_to_apic_id(int numa_node_id);
 
 /* Interrupts */
 int kfd_interrupt_init(struct kfd_dev *dev);

drivers/gpu/drm/amd/amdkfd/kfd_topology.c

@@ -28,6 +28,8 @@
 #include <linux/hash.h>
 #include <linux/cpufreq.h>
 #include <linux/log2.h>
+#include <linux/dmi.h>
+#include <linux/atomic.h>
 
 #include "kfd_priv.h"
 #include "kfd_crat.h"
@@ -36,9 +38,10 @@
 
 /* topology_device_list - Master list of all topology devices */
 static struct list_head topology_device_list;
-struct kfd_system_properties sys_props;
+static struct kfd_system_properties sys_props;
 
 static DECLARE_RWSEM(topology_lock);
+static atomic_t topology_crat_proximity_domain;
 
 struct kfd_dev *kfd_device_by_id(uint32_t gpu_id)
 {
@@ -691,12 +694,92 @@ static void kfd_topology_update_device_list(struct list_head *temp_list,
 	}
 }
 
+static void kfd_debug_print_topology(void)
+{
+	struct kfd_topology_device *dev;
+
+	down_read(&topology_lock);
+
+	dev = list_last_entry(&topology_device_list,
+			struct kfd_topology_device, list);
+	if (dev) {
+		if (dev->node_props.cpu_cores_count &&
+				dev->node_props.simd_count) {
+			pr_info("Topology: Add APU node [0x%0x:0x%0x]\n",
+				dev->node_props.device_id,
+				dev->node_props.vendor_id);
+		} else if (dev->node_props.cpu_cores_count)
+			pr_info("Topology: Add CPU node\n");
+		else if (dev->node_props.simd_count)
+			pr_info("Topology: Add dGPU node [0x%0x:0x%0x]\n",
+				dev->node_props.device_id,
+				dev->node_props.vendor_id);
+	}
+	up_read(&topology_lock);
+}
+
+/* Helper function for intializing platform_xx members of
+ * kfd_system_properties. Uses OEM info from the last CPU/APU node.
+ */
+static void kfd_update_system_properties(void)
+{
+	struct kfd_topology_device *dev;
+
+	down_read(&topology_lock);
+	dev = list_last_entry(&topology_device_list,
+			struct kfd_topology_device, list);
+	if (dev) {
+		sys_props.platform_id =
+			(*((uint64_t *)dev->oem_id)) & CRAT_OEMID_64BIT_MASK;
+		sys_props.platform_oem = *((uint64_t *)dev->oem_table_id);
+		sys_props.platform_rev = dev->oem_revision;
+	}
+	up_read(&topology_lock);
+}
+
+static void find_system_memory(const struct dmi_header *dm,
+	void *private)
+{
+	struct kfd_mem_properties *mem;
+	u16 mem_width, mem_clock;
+	struct kfd_topology_device *kdev =
+		(struct kfd_topology_device *)private;
+	const u8 *dmi_data = (const u8 *)(dm + 1);
+
+	if (dm->type == DMI_ENTRY_MEM_DEVICE && dm->length >= 0x15) {
+		mem_width = (u16)(*(const u16 *)(dmi_data + 0x6));
+		mem_clock = (u16)(*(const u16 *)(dmi_data + 0x11));
+		list_for_each_entry(mem, &kdev->mem_props, list) {
+			if (mem_width != 0xFFFF && mem_width != 0)
+				mem->width = mem_width;
+			if (mem_clock != 0)
+				mem->mem_clk_max = mem_clock;
+		}
+	}
+}
+/* kfd_add_non_crat_information - Add information that is not currently
+ *	defined in CRAT but is necessary for KFD topology
+ * @dev - topology device to which addition info is added
+ */
+static void kfd_add_non_crat_information(struct kfd_topology_device *kdev)
+{
+	/* Check if CPU only node. */
+	if (!kdev->gpu) {
+		/* Add system memory information */
+		dmi_walk(find_system_memory, kdev);
+	}
+	/* TODO: For GPU node, rearrange code from kfd_topology_add_device */
+}
+
 int kfd_topology_init(void)
 {
 	void *crat_image = NULL;
 	size_t image_size = 0;
 	int ret;
 	struct list_head temp_topology_device_list;
+	int cpu_only_node = 0;
+	struct kfd_topology_device *kdev;
+	int proximity_domain;
 
 	/* topology_device_list - Master list of all topology devices
 	 * temp_topology_device_list - temporary list created while parsing CRAT
@@ -711,36 +794,78 @@ int kfd_topology_init(void)
 
 	memset(&sys_props, 0, sizeof(sys_props));
 
+	/* Proximity domains in ACPI CRAT tables start counting at
+	 * 0. The same should be true for virtual CRAT tables created
+	 * at this stage. GPUs added later in kfd_topology_add_device
+	 * use a counter.
+	 */
+	proximity_domain = 0;
+
 	/*
-	 * Get the CRAT image from the ACPI
+	 * Get the CRAT image from the ACPI. If ACPI doesn't have one
+	 * create a virtual CRAT.
+	 * NOTE: The current implementation expects all AMD APUs to have
+	 *	CRAT. If no CRAT is available, it is assumed to be a CPU
 	 */
 	ret = kfd_create_crat_image_acpi(&crat_image, &image_size);
 	if (!ret) {
 		ret = kfd_parse_crat_table(crat_image,
-					   &temp_topology_device_list, 0);
-		if (ret)
+					   &temp_topology_device_list,
+					   proximity_domain);
+		if (ret) {
+			kfd_release_topology_device_list(
+				&temp_topology_device_list);
+			kfd_destroy_crat_image(crat_image);
+			crat_image = NULL;
+		}
+	}
+
+	if (!crat_image) {
+		ret = kfd_create_crat_image_virtual(&crat_image, &image_size,
+						    COMPUTE_UNIT_CPU, NULL,
+						    proximity_domain);
+		cpu_only_node = 1;
+		if (ret) {
+			pr_err("Error creating VCRAT table for CPU\n");
+			return ret;
+		}
+
+		ret = kfd_parse_crat_table(crat_image,
+					   &temp_topology_device_list,
+					   proximity_domain);
+		if (ret) {
+			pr_err("Error parsing VCRAT table for CPU\n");
 			goto err;
-	} else if (ret == -ENODATA) {
-		/* TODO: Create fake CRAT table */
-		ret = 0;
-		goto err;
-	} else {
-		pr_err("Couldn't get CRAT table size from ACPI\n");
-		goto err;
+		}
 	}
 
 	down_write(&topology_lock);
 	kfd_topology_update_device_list(&temp_topology_device_list,
 					&topology_device_list);
+	atomic_set(&topology_crat_proximity_domain, sys_props.num_devices-1);
 	ret = kfd_topology_update_sysfs();
 	up_write(&topology_lock);
 
 	if (!ret) {
 		sys_props.generation_count++;
+		kfd_update_system_properties();
+		kfd_debug_print_topology();
 		pr_info("Finished initializing topology\n");
 	} else
 		pr_err("Failed to update topology in sysfs ret=%d\n", ret);
 
+	/* For nodes with GPU, this information gets added
+	 * when GPU is detected (kfd_topology_add_device).
+	 */
+	if (cpu_only_node) {
+		/* Add additional information to CPU only node created above */
+		down_write(&topology_lock);
+		kdev = list_first_entry(&topology_device_list,
+				struct kfd_topology_device, list);
+		up_write(&topology_lock);
+		kfd_add_non_crat_information(kdev);
+	}
+
 err:
 	kfd_destroy_crat_image(crat_image);
 	return ret;
@@ -754,21 +879,6 @@ void kfd_topology_shutdown(void)
 	up_write(&topology_lock);
 }
 
-static void kfd_debug_print_topology(void)
-{
-	struct kfd_topology_device *dev;
-	uint32_t i = 0;
-
-	pr_info("DEBUG PRINT OF TOPOLOGY:");
-	list_for_each_entry(dev, &topology_device_list, list) {
-		pr_info("Node: %d\n", i);
-		pr_info("\tGPU assigned: %s\n", (dev->gpu ? "yes" : "no"));
-		pr_info("\tCPU count: %d\n", dev->node_props.cpu_cores_count);
-		pr_info("\tSIMD count: %d\n", dev->node_props.simd_count);
-		i++;
-	}
-}
-
 static uint32_t kfd_generate_gpu_id(struct kfd_dev *gpu)
 {
 	uint32_t hashout;
@@ -954,6 +1064,34 @@ int kfd_topology_enum_kfd_devices(uint8_t idx, struct kfd_dev **kdev)
 
 }
 
+static int kfd_cpumask_to_apic_id(const struct cpumask *cpumask)
+{
+	const struct cpuinfo_x86 *cpuinfo;
+	int first_cpu_of_numa_node;
+
+	if (!cpumask || cpumask == cpu_none_mask)
+		return -1;
+	first_cpu_of_numa_node = cpumask_first(cpumask);
+	if (first_cpu_of_numa_node >= nr_cpu_ids)
+		return -1;
+	cpuinfo = &cpu_data(first_cpu_of_numa_node);
+
+	return cpuinfo->apicid;
+}
+
+/* kfd_numa_node_to_apic_id - Returns the APIC ID of the first logical processor
+ *	of the given NUMA node (numa_node_id)
+ * Return -1 on failure
+ */
+int kfd_numa_node_to_apic_id(int numa_node_id)
+{
+	if (numa_node_id == -1) {
+		pr_warn("Invalid NUMA Node. Use online CPU mask\n");
+		return kfd_cpumask_to_apic_id(cpu_online_mask);
+	}
+	return kfd_cpumask_to_apic_id(cpumask_of_node(numa_node_id));
+}
+
 #if defined(CONFIG_DEBUG_FS)
 
 int kfd_debugfs_hqds_by_device(struct seq_file *m, void *data)

drivers/gpu/drm/amd/amdkfd/kfd_topology.h

@@ -148,6 +148,9 @@ struct kfd_topology_device {
 	struct attribute		attr_gpuid;
 	struct attribute		attr_name;
 	struct attribute		attr_props;
+	uint8_t				oem_id[CRAT_OEMID_LENGTH];
+	uint8_t				oem_table_id[CRAT_OEMTABLEID_LENGTH];
+	uint32_t			oem_revision;
 };
 
 struct kfd_system_properties {