Fallback to kfd node when VRAM sysfs not available

The driver may not expose VRAM sysfs in certain system. Add a
fallback to it.

Change-Id: Ib3be71b4f4d2c79318d5026b0a97f3657d8a97b6

include/rocm_smi/kfd_ioctl.h

@@ -36,6 +36,12 @@ struct kfd_ioctl_get_version_args {
   __u32 minor_version;  /* from KFD */
 };
 
+struct kfd_ioctl_get_available_memory_args {
+    __u64 available;    /* from KFD */
+    __u32 gpu_id;       /* to KFD */
+    __u32 pad;
+};
+
 /* For kfd_ioctl_create_queue_args.queue_type. */
 #define KFD_IOC_QUEUE_TYPE_COMPUTE    0x0
 #define KFD_IOC_QUEUE_TYPE_SDMA      0x1
@@ -726,6 +732,10 @@ struct kfd_ioctl_cross_memory_copy_args {
 #define AMDKFD_IOC_CROSS_MEMORY_COPY    \
     AMDKFD_IOWR(0x22, struct kfd_ioctl_cross_memory_copy_args)
 
+
+#define AMDKFD_IOC_AVAILABLE_MEMORY     \
+        AMDKFD_IOWR(0x23, struct kfd_ioctl_get_available_memory_args)
+
 #define AMDKFD_COMMAND_START    0x01
 #undef AMDKFD_COMMAND_END
 #define AMDKFD_COMMAND_END    0x22

include/rocm_smi/rocm_smi_kfd.h

@@ -80,6 +80,10 @@ class KFDNode {
     uint32_t amdgpu_dev_index(void) const {return amdgpu_dev_index_;}
     void set_amdgpu_dev_index(uint32_t val) {amdgpu_dev_index_ = val;}
 
+    // Get memory from kfd
+    int get_total_memory(uint64_t* total);
+    int get_used_memory(uint64_t* used);
+
  private:
     uint32_t node_indx_;
     uint32_t amdgpu_dev_index_;