[QST] What is the definition and difference of two partition methods in cute?

[ziyuhuang123]

  TiledMMA tiled_mma;
  auto thr_mma = tiled_mma.get_slice(threadIdx.x);
  auto tAgA = thr_mma.partition_A(gA);  // (MMA, MMA_M, MMA_K, num_tile_k)
  auto tBgB = thr_mma.partition_B(gB);  // (MMA, MMA_N, MMA_K, num_tile_k)
  auto tCgC = thr_mma.partition_C(gC);  // (MMA, MMA_M, MMA_N)

  auto tArA = thr_mma.partition_fragment_A(gA(_, _, 0));  // (MMA, MMA_M, MMA_K)
  auto tBrB = thr_mma.partition_fragment_B(gB(_, _, 0));  // (MMA, MMA_N, MMA_K)
  auto tCrC = thr_mma.partition_fragment_C(gC(_, _));     // (MMA, MMA_M, MMA_N)

  auto tCsB = local_partition(sB, tC, threadIdx.x, Step< X,_1>{});   // (THR_N,BLK_K)
  // Partition gC (M,N) by the tile of tC
  auto tCgC = local_partition(gC, tC, threadIdx.x, Step<_1,_1>{});   // (THR_M,THR_N)

I can not find detailed doc for these two partition methods, could anyone provide usage description and difference for them? Like, I do not understand how data are allocated across threadIdx.x, if I have .y, how can I input them? How is Step works?

[mnicely]

Dup. Closing