nrLDPC_decoder_LYC.cu 15 KB
Newer Older
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552
 /*! \file PHY/CODING/nrLDPC_decoder_LYC/nrLDPC_decoder_LYC.cu
 * \brief LDPC cuda support BG1 all length
 * \author NCTU OpinConnect Terng-Yin Hsu,WEI-YING,LIN
 * \email tyhsu@cs.nctu.edu.tw
 * \date 13-05-2020
 * \version 
 * \note
 * \warning
 */

#include <stdio.h>
#include <unistd.h>
#include <cuda_runtime.h>
#include <cuda.h>
#include "PHY/CODING/nrLDPC_decoder/nrLDPC_types.h"
#include "PHY/CODING/nrLDPC_decoder/nrLDPCdecoder_defs.h"

#include "bgs/BG1_I0"
#include "bgs/BG1_I1"
#include "bgs/BG1_I2"
#include "bgs/BG1_I3"
#include "bgs/BG1_I4"
#include "bgs/BG1_I5"
#include "bgs/BG1_I6"
#include "bgs/BG1_I7"
#include "bgs/BG2_I0"
#include "bgs/BG2_I1"
#include "bgs/BG2_I2"
#include "bgs/BG2_I3"
#include "bgs/BG2_I4"
#include "bgs/BG2_I5"
#include "bgs/BG2_I6"
#include "bgs/BG2_I7"

#define MAX_ITERATION 2
#define MC	1

#define cudaCheck(ans) { cudaAssert((ans), __FILE__, __LINE__); }
inline void cudaAssert(cudaError_t code, const char *file, int line)
{
   if (code != cudaSuccess){
      fprintf(stderr,"GPUassert: %s %s %d\n", cudaGetErrorString(code), file, line);
      exit(code);
   }
}

typedef struct{
  char x;
  char y;
  short value;
} h_element;
#include "bgs/BG1_compact_in_C.h"

__device__ char dev_const_llr[68*384];
__device__ char dev_dt [46*68*384];
__device__ char dev_llr[68*384];
__device__ unsigned char dev_tmp[68*384];

h_element h_compact1 [46*19] = {};
h_element h_compact2 [68*30] = {};

__device__  h_element dev_h_compact1[46*19];  // used in kernel 1
__device__  h_element dev_h_compact2[68*30];  // used in kernel 2

// __device__ __constant__ h_element dev_h_compact1[46*19];  // used in kernel 1
// __device__ __constant__ h_element dev_h_compact2[68*30];  // used in kernel 2

// row and col element count
__device__ __constant__ char h_ele_row_bg1_count[46] = {
	19, 19, 19, 19, 3,  8,  9,  7, 10,  9,
	7,  8,  7,  6,  7,  7,  6,  6,  6,  6,  
	6,  6,  5,  5,  6,  5,  5,  4,  5,  5,  
	5,  5,  5,  5,  5,  5,  5,  4,  5,  5,  
	4,  5,  4,  5,  5,  4};
__device__ __constant__ char h_ele_col_bg1_count[68] = {
	30, 28,  7, 11,  9,  4,  8, 12,  8,  7, 
	12, 10, 12, 11, 10,  7, 10, 10, 13,  7,  
	8,  11, 12,  5,  6,  6,  1,  1,  1,  1,  
	1,   1,  1,  1,  1,  1,  1,  1,  1,  1,  
	1,   1,  1,  1,  1,  1,  1,  1,  1,  1,  
	1,   1,  1,  1,  1,  1,  1,  1,  1,  1,  
	1,   1,  1,  1,  1,  1,  1,  1};
__device__ __constant__ char h_ele_row_bg2_count[42] = { 
	8, 10,  8, 10,  4,  6,  6,  6,  4,  5, 
	5,  5,  4,  5,  5,  4,  5,  5,  4,  4,
	4,  4,  3,  4,  4,  3,  5,  3,  4,  3,
	5,  3,  4,  4,  4,  4,  4,  3,  4,  4, 
	4,  4};
__device__ __constant__ char h_ele_col_bg2_count[52] = {
	22, 23, 10,  5,  5, 14,  7, 13,  6,  8, 
	9,  16,  9, 12,  1,  1,  1,  1,  1,  1,
	1,   1,  1,  1,  1,  1,  1,  1,  1,  1,
	1,   1,  1,  1,  1,  1,  1,  1,  1,  1,
	1,   1,  1,  1,  1,  1,  1,  1,  1,  1, 
	1,   1};


__global__ void warmup()
{
	// warm up gpu for time measurement
}

extern "C"
void warmup_for_GPU(){
	
	warmup<<<20,1024 >>>();

}

extern "C"
void set_compact_BG(int Zc,short BG){
	
	int row,col;
	if(BG == 1){
		row = 46;
		col = 68;
	}
	else{
		row = 42;
		col = 52;
	}
	int compact_row = 30; 
	int compact_col = 19;
	if(BG==2){compact_row = 10, compact_col = 23;}
	int memorySize_h_compact1 = row * compact_col * sizeof(h_element);
	int memorySize_h_compact2 = compact_row * col * sizeof(h_element);
	int lift_index = 0;
	short lift_set[][9] = {
		{2,4,8,16,32,64,128,256},
		{3,6,12,24,48,96,192,384},
		{5,10,20,40,80,160,320},
		{7,14,28,56,112,224},
		{9,18,36,72,144,288},
		{11,22,44,88,176,352},
		{13,26,52,104,208},
		{15,30,60,120,240},
		{0}
	};
	
	for(int i = 0; lift_set[i][0] != 0; i++){
		for(int j = 0; lift_set[i][j] != 0; j++){
			if(Zc == lift_set[i][j]){
				lift_index = i;
				break;
			}
		}
	}
	printf("\nZc = %d BG = %d\n",Zc,BG);
	switch(lift_index){
			case 0:
				cudaCheck( cudaMemcpyToSymbol(dev_h_compact1, host_h_compact1_I0, memorySize_h_compact1) );
				cudaCheck( cudaMemcpyToSymbol(dev_h_compact2, host_h_compact2_I0, memorySize_h_compact2) );
				break;
			case 1:
				cudaCheck( cudaMemcpyToSymbol(dev_h_compact1, host_h_compact1_I1, memorySize_h_compact1) );
				cudaCheck( cudaMemcpyToSymbol(dev_h_compact2, host_h_compact2_I1, memorySize_h_compact2) );
				break;
			case 2:
				cudaCheck( cudaMemcpyToSymbol(dev_h_compact1, host_h_compact1_I2, memorySize_h_compact1) );
				cudaCheck( cudaMemcpyToSymbol(dev_h_compact2, host_h_compact2_I2, memorySize_h_compact2) );
				break;
			case 3:
				cudaCheck( cudaMemcpyToSymbol(dev_h_compact1, host_h_compact1_I3, memorySize_h_compact1) );
				cudaCheck( cudaMemcpyToSymbol(dev_h_compact2, host_h_compact2_I3, memorySize_h_compact2) );
				break;
			case 4:
				cudaCheck( cudaMemcpyToSymbol(dev_h_compact1, host_h_compact1_I4, memorySize_h_compact1) );
				cudaCheck( cudaMemcpyToSymbol(dev_h_compact2, host_h_compact2_I4, memorySize_h_compact2) );
				break;
			case 5:
				cudaCheck( cudaMemcpyToSymbol(dev_h_compact1, host_h_compact1_I5, memorySize_h_compact1) );
				cudaCheck( cudaMemcpyToSymbol(dev_h_compact2, host_h_compact2_I5, memorySize_h_compact2) );
				break;
			case 6:
				cudaCheck( cudaMemcpyToSymbol(dev_h_compact1, host_h_compact1_I6, memorySize_h_compact1) );
				cudaCheck( cudaMemcpyToSymbol(dev_h_compact2, host_h_compact2_I6, memorySize_h_compact2) );
				break;
			case 7:
				cudaCheck( cudaMemcpyToSymbol(dev_h_compact1, host_h_compact1_I7, memorySize_h_compact1) );
				cudaCheck( cudaMemcpyToSymbol(dev_h_compact2, host_h_compact2_I7, memorySize_h_compact2) );
				break;
		}
	
	// return 0;
}


// Kernel 1
__global__ void ldpc_cnp_kernel_1st_iter(/*char * dev_llr,*/ int BG, int row, int col, int Zc)
{
//	if(blockIdx.x == 0 && threadIdx.x == 1) printf("cnp %d\n", threadIdx.x);
	int iMCW = blockIdx.y;		// codeword id
	int iBlkRow = blockIdx.x;	// block row in h_base
	int iBlkCol;				// block col in h_base
	int iSubRow = threadIdx.x;	// row index in sub_block of h_base
	int iCol;					// overall col index in h_base
	int offsetR;
	int shift_t;

//	For 2-min algorithm.
	int Q_sign = 0;
	int sq;
	int Q, Q_abs;
	int R_temp;

	int sign = 1;
	int rmin1 = INT32_MAX;
	int rmin2 = INT32_MAX;
	char idx_min = 0;

	h_element h_element_t;
	int s = (BG==1)? h_ele_row_bg1_count[iBlkRow]:h_ele_row_bg2_count[iBlkRow];
	offsetR = (iMCW * row*col*Zc) + iBlkRow * Zc + iSubRow;	// row*col*Zc = size of dev_dt
//	if(blockIdx.x == 0 && threadIdx.x == 1) printf("s: %d, offset %d\n", s, offsetR);
//	The 1st recursion
	for(int i = 0; i < s; i++) // loop through all the ZxZ sub-blocks in a row
	{
		h_element_t = dev_h_compact1[i*row+iBlkRow];	// compact_col == row

		iBlkCol = h_element_t.y;
		shift_t = h_element_t.value;

		shift_t = (iSubRow + shift_t) % Zc;
		iCol = (iMCW * col*Zc) + iBlkCol * Zc + shift_t;	// col*Zc = size of llr
		Q = dev_llr[iCol];
		Q_abs = (Q>0)? Q : -Q;
		sq = Q < 0;
//		if(blockIdx.x == 0 && threadIdx.x == 1) printf("i %d, icol %d, Q: %d\n", i, iCol, Q);
		// quick version
		sign = sign * (1 - sq * 2);
		Q_sign |= sq << i;

		if (Q_abs < rmin1){
			rmin2 = rmin1;
			rmin1 = Q_abs;
			idx_min = i;
		} else if (Q_abs < rmin2){
			rmin2 = Q_abs;
		}
	}

//	if(blockIdx.x == 0 && threadIdx.x == 1)printf("min1 %d, min2 %d, min1_idx %d\n", rmin1, rmin2, idx_min);

//	The 2nd recursion
	for(int i = 0; i < s; i++){
		// v0: Best performance so far. 0.75f is the value of alpha.
		sq = 1 - 2 * ((Q_sign >> i) & 0x01);
		R_temp = 0.75f * sign * sq * (i != idx_min ? rmin1 : rmin2);
		// write results to global memory
		h_element_t = dev_h_compact1[i*row+iBlkRow];
		int addr_temp = offsetR + h_element_t.y * row * Zc;
		dev_dt[addr_temp] = R_temp;
//		if(blockIdx.x == 0 && threadIdx.x == 1)printf("R_temp %d, temp_addr %d\n", R_temp, addr_temp);
	}	
}

// Kernel_1
__global__ void ldpc_cnp_kernel(/*char * dev_llr, char * dev_dt,*/ int BG, int row, int col, int Zc)
{
//	if(blockIdx.x == 0 && threadIdx.x == 1) printf("cnp\n");
	int iMCW = blockIdx.y;
	int iBlkRow = blockIdx.x;	// block row in h_base
	int iBlkCol; 				// block col in h_base
	int iSubRow = threadIdx.x;	// row index in sub_block of h_base
	int iCol; 					// overall col index in h_base
	int offsetR;
	int shift_t;

//	For 2-min algorithm.
	int Q_sign = 0;
	int sq;
	int Q, Q_abs;
	int R_temp;

	int sign = 1;
	int rmin1 = INT32_MAX;
	int rmin2 = INT32_MAX;
	char idx_min = 0;

	h_element h_element_t;
	int s = (BG==1)? h_ele_row_bg1_count[iBlkRow]: h_ele_row_bg2_count[iBlkRow];
	offsetR = (iMCW *row*col*Zc) + iBlkRow * Zc + iSubRow;	// row * col * Zc = size of dev_dt
//	if(blockIdx.x == 0 && threadIdx.x == 1) printf("s: %d, offset %d\n", s, offsetR);
//	The 1st recursion
	for(int i = 0; i < s; i++) // loop through all the ZxZ sub-blocks in a row
	{
		h_element_t = dev_h_compact1[i*row+iBlkRow];

		iBlkCol = h_element_t.y;
		shift_t = h_element_t.value;
		shift_t = (iSubRow + shift_t) % Zc;
		iCol = iBlkCol * Zc + shift_t;
		
		R_temp = dev_dt[offsetR + iBlkCol * row * Zc];

		Q = dev_llr[iMCW * (col*Zc) + iCol] - R_temp;
		Q_abs = (Q>0)? Q : -Q;
//		if(blockIdx.x == 0 && threadIdx.x == 1) printf("i %d, icol %d, Q: %d\n", i, iCol, Q);
		sq = Q < 0;
		sign = sign * (1 - sq * 2);
		Q_sign |= sq << i;

		if (Q_abs < rmin1){
			rmin2 = rmin1;
			rmin1 = Q_abs;
			idx_min = i;
		} else if (Q_abs < rmin2){
			rmin2 = Q_abs;
		}
		
	}

//	if(blockIdx.x == 0 && threadIdx.x == 1)printf("min1 %d, min2 %d, min1_idx %d\n", rmin1, rmin2, idx_min);
	
//	The 2nd recursion
	for(int i = 0; i < s; i ++){
		sq = 1 - 2 * ((Q_sign >> i) & 0x01);
		R_temp = 0.75f * sign * sq * (i != idx_min ? rmin1 : rmin2);
		

		// write results to global memory
		h_element_t = dev_h_compact1[i*row+iBlkRow];
		int addr_temp = h_element_t.y * row * Zc + offsetR;
		dev_dt[addr_temp] = R_temp;
//		if(blockIdx.x == 0 && threadIdx.x == 1)printf("R_temp %d, temp_addr %d\n", R_temp, addr_temp);
	}
}

// Kernel 2: VNP processing
__global__ void
ldpc_vnp_kernel_normal(/*char * dev_llr, char * dev_dt, char * dev_const_llr,*/ int BG, int row, int col, int Zc)
{	
	int iMCW = blockIdx.y;
	int iBlkCol = blockIdx.x;
	int iBlkRow;
	int iSubCol = threadIdx.x;
	int iRow;
	int iCol;

	int shift_t, sf;
	int APP;

	h_element h_element_t;

	// update all the llr values
	iCol = iBlkCol * Zc + iSubCol;
	APP = dev_const_llr[iMCW *col*Zc + iCol];
	int offsetDt = iMCW *row*col*Zc + iBlkCol * row * Zc;
	int s = (BG==1)? h_ele_col_bg1_count[iBlkCol]:h_ele_col_bg2_count[iBlkCol];
	
	for(int i = 0; i < s; i++)
	{
		h_element_t = dev_h_compact2[i*col+iBlkCol];

		shift_t = h_element_t.value%Zc;
		iBlkRow = h_element_t.x;

		sf = iSubCol - shift_t;
		sf = (sf + Zc) % Zc;

		iRow = iBlkRow * Zc + sf;
		APP = APP + dev_dt[offsetDt + iRow];
	}
	if(APP > SCHAR_MAX)	APP = SCHAR_MAX;
	if(APP < SCHAR_MIN)	APP = SCHAR_MIN;
	// write back to device global memory
	dev_llr[iMCW *col*Zc + iCol] = APP;
}


__global__ void pack_decoded_bit(/*char *dev, unsigned char *host,*/ int col, int Zc)
{
	__shared__ unsigned char tmp[128];
	int iMCW = blockIdx.y;
	int tid = iMCW * col*Zc + blockIdx.x*128 + threadIdx.x;
	int btid = threadIdx.x;
	tmp[btid] = 0;
	
	if(dev_llr[tid] < 0){
		tmp[btid] = 1 << (7-(btid&7));
	}
	__syncthreads();
	
	if(threadIdx.x < 16){
		dev_tmp[iMCW * col*Zc + blockIdx.x*16+threadIdx.x] = 0;
		for(int i = 0; i < 8; i++){
			dev_tmp[iMCW * col*Zc + blockIdx.x*16+threadIdx.x] += tmp[threadIdx.x*8+i];
		}
	}
}

void read_BG(int BG, int *h, int row, int col)
{
	int compact_row = 30, compact_col = 19;
	if(BG==2){compact_row = 10, compact_col = 23;}
	
	h_element h_element_temp;

	// init the compact matrix
	for(int i = 0; i < compact_col; i++){
		for(int j = 0; j < row; j++){
			h_element_temp.x = 0;
			h_element_temp.y = 0;
			h_element_temp.value = -1;
			h_compact1[i*row+j] = h_element_temp; // h[i][0-11], the same column
        }
    }
	// scan the h matrix, and gengerate compact mode of h
	for(int i = 0; i < row; i++){
		int k = 0;
		for(int j = 0; j < col; j++){
			if(h[i*col+j] != -1){
				h_element_temp.x = i;
				h_element_temp.y = j;
				h_element_temp.value = h[i*col+j];
				h_compact1[k*row+i] = h_element_temp;
				k++;
            }
        }
    }
	
	// h_compact2
	// init the compact matrix
	for(int i = 0; i < compact_row; i++){
		for(int j = 0; j < col; j++){
			h_element_temp.x = 0;
			h_element_temp.y = 0;
			h_element_temp.value = -1;
			h_compact2[i*col+j] = h_element_temp;
        }
    }

	for(int j = 0; j < col; j++){
		int k=0;
		for(int i = 0; i < row; i++){
			if(h[i*col+j] != -1){
				// although h is transposed, the (x,y) is still (iBlkRow, iBlkCol)
				h_element_temp.x = i; 
				h_element_temp.y = j;
				h_element_temp.value = h[i*col+j];
				h_compact2[k*col+j] = h_element_temp;
				k++;
			}
		}
	}
	
	/*
	for(int i = 0; i < compact_col; i++){
		for(int j = 0; j < row; j++){
			printf("%3d, ", h_compact1[i*row+j].value);
		}
		printf("\n");
	}
	
	for(int i = 0; i < compact_row; i++){
		for(int j = 0; j < col; j++){
			printf("%3d,", h_compact2[i*col+j].value);
		}
		printf("\n");
	}
	*/
}

extern "C"
void init_LLR_DMA_for_CUDA(t_nrLDPC_dec_params* p_decParams, int8_t* p_llr, int8_t* p_out, int block_length){
	
	uint16_t Zc          = p_decParams->Z;
    uint8_t  BG         = p_decParams->BG;
	uint8_t row,col;
	if(BG == 1){
		row = 46;
		col = 68;
	}
	else{
		row = 42;
		col = 52;
	}
	unsigned char *hard_decision = (unsigned char*)p_out;
	int memorySize_llr_cuda = col * Zc * sizeof(char) * MC;
	cudaCheck( cudaMemcpyToSymbol(dev_const_llr, p_llr, memorySize_llr_cuda) );
	cudaCheck( cudaMemcpyToSymbol(dev_llr, p_llr, memorySize_llr_cuda) );
	cudaDeviceSynchronize();
	
}

extern "C"
int32_t nrLDPC_decoder_LYC(t_nrLDPC_dec_params* p_decParams, int8_t* p_llr, int8_t* p_out, int block_length, time_stats_t *time_decoder)
{


    uint16_t Zc          = p_decParams->Z;
    uint8_t  BG         = p_decParams->BG;
    uint8_t  numMaxIter = p_decParams->numMaxIter;
    e_nrLDPC_outMode outMode = p_decParams->outMode;
	cudaError_t cudaStatus;
	uint8_t row,col;
	if(BG == 1){
		row = 46;
		col = 68;
	}
	else{
		row = 42;
		col = 52;
	}

//	alloc memory
	unsigned char *hard_decision = (unsigned char*)p_out;
//	gpu
	int memorySize_llr_cuda = col * Zc * sizeof(char) * MC;
	cudaCheck( cudaMemcpyToSymbol(dev_const_llr, p_llr, memorySize_llr_cuda) );
	cudaCheck( cudaMemcpyToSymbol(dev_llr, p_llr, memorySize_llr_cuda) );
	
// Define CUDA kernel dimension
	int blockSizeX = Zc;
	dim3 dimGridKernel1(row, MC, 1); 	// dim of the thread blocks
	dim3 dimBlockKernel1(blockSizeX, 1, 1);

    dim3 dimGridKernel2(col, MC, 1);
    dim3 dimBlockKernel2(blockSizeX, 1, 1);	
	cudaDeviceSynchronize();

// lauch kernel 

	for(int ii = 0; ii < MAX_ITERATION; ii++){
		// first kernel	
		if(ii == 0){
			ldpc_cnp_kernel_1st_iter 
			<<<dimGridKernel1, dimBlockKernel1>>>
			(/*dev_llr,*/ BG, row, col, Zc);
		}else{
			ldpc_cnp_kernel
			<<<dimGridKernel1, dimBlockKernel1>>>
			(/*dev_llr,*/ BG, row, col, Zc);
		}
		// second kernel
		ldpc_vnp_kernel_normal
		<<<dimGridKernel2, dimBlockKernel2>>>
		// (dev_llr, dev_const_llr,BG, row, col, Zc);
		(BG, row, col, Zc);
	}
	
	int pack = (block_length/128)+1;
	dim3 pack_block(pack, MC, 1);
	pack_decoded_bit<<<pack_block,128>>>(/*dev_llr,*/ /*dev_tmp,*/ col, Zc);
	
	cudaCheck( cudaMemcpyFromSymbol((void*)hard_decision, (const void*)dev_tmp, (block_length/8)*sizeof(unsigned char)) );
	cudaDeviceSynchronize();
	

	return MAX_ITERATION;
	
}