hexagon: optimization for HMX mat_mul (#21554)

* hexagon: add async HMX worker

Introduce hmx-worker (dedicated thread for HMX compute) to overlap HMX
matmul with HVX dequant/DMA stages in the pipeline path, replacing the
previous synchronous HMX calls that blocked the main thread.

* hexagon: cost-based VTCM chunk search for out-stationary matmul

* hexagon: fix futex race in hmx_worker_drain
Store the boolean to local variable avoid atomic load twice

* hex-mm: hmx optimize scatter/transpose and use HMX intrinsics

* hex-vmem: drop vmem limit a touch under 3GB on v73

* hexagon: add fwd declaration of htp_context

* hex-hmx: replace hmx-worker with hmx-queue that mimics dma-queue interface

Simplifies the overall implemantion, reduces thread wakeup roundtrips.

* hex-mm: add debug log to hmx work func called from hmx-queue

* Update hmx-queue.h

Co-authored-by: Max Krasnyansky <max.krasnyansky@gmail.com>

---------

Co-authored-by: Kim-Chyan Gan <kgan@qti.qualcomm.com>
Co-authored-by: Max Krasnyansky <maxk@qti.qualcomm.com>
Co-authored-by: Max Krasnyansky <max.krasnyansky@gmail.com>
This commit is contained in:
Yiwei Shao
2026-04-14 14:09:03 -07:00
committed by GitHub
co-authored by Max Krasnyansky Kim-Chyan Gan Max Krasnyansky
parent fae3a28070
commit 5d14e5d19b
10 changed files with 589 additions and 197 deletions
+251 -137
View File
@@ -16,14 +16,16 @@
#include "ggml-common.h"
#include "hex-dma.h"
#include "worker-pool.h"
#include "hvx-utils.h"
#include "hvx-dump.h"
#include "worker-pool.h"
#include "htp-ctx.h"
#include "htp-ops.h"
#include "hmx-utils.h"
#include "hmx-ops.h"
#include "hmx-utils.h"
#include "hmx-queue.h"
#include "hmx-profile.h"
static const __fp16 q4_0_to_fp16_lut[64] __attribute__((aligned(VLEN))) = {
@@ -47,7 +49,8 @@ static const __fp16 iq4_nl_to_fp16_lut[64] __attribute__((aligned(VLEN))) = {
static const int32_t weight_transpose_scatter_offsets[32] __attribute__((aligned(VLEN))) = {
0*128, 1*128, 2*128, 3*128, 4*128, 5*128, 6*128, 7*128,
8*128, 9*128, 10*128, 11*128, 12*128, 13*128, 14*128, 15*128,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
16*128, 17*128, 18*128, 19*128, 20*128, 21*128, 22*128, 23*128,
24*128, 25*128, 26*128, 27*128, 28*128, 29*128, 30*128, 31*128
};
// Scales per x4x2 logical block: 8 × sizeof(__fp16) = 16 bytes
@@ -109,36 +112,45 @@ static inline bool hmx_add_overflow(size_t a, size_t b, size_t *out) {
return false;
}
// Search for optimal (mc, nc) chunk sizes that maximize mc * nc within VTCM budget.
// Search for optimal (mc, nc) chunk sizes within VTCM budget.
//
// Cost model: total = nc * per_n_cost + mc * per_m_cost + mc * nc * per_mn_cost + overhead
// per_n_cost: bytes per nc column (weight + scratch buffers)
// per_m_cost: bytes per mc row (activation)
// per_mn_cost: bytes per mc*nc element (output)
// overhead: fixed bytes (scales 256B, eye_tile 2048B, etc.)
// VTCM model: nc * per_n_cost + mc * per_m_cost + mc * nc * per_mn_cost + overhead
//
// Minimize ceil(m/mc) * m_block_cost + ceil(n/nc) * n_block_cost.
// All matmul paths repeat weight processing per M-block and activation loading
// per N-block, so discrete block counts drive total overhead.
// Tie-break: when cost is equal, prefer larger mc * nc.
//
// Caller-provided coefficients:
// m_block_cost: penalty per extra M-block (weight redundancy, scales with n).
// n_block_cost: penalty per extra N-block (activation redundancy, scales with m).
//
// Algorithm: nc sweeps from n_max down by 32, analytically solving for mc_max.
// Returns 0 on success, -1 if VTCM is insufficient.
static int hmx_compute_chunks(
size_t vtcm_total, size_t overhead,
size_t per_n_cost, size_t per_m_cost, size_t per_mn_cost,
int m, int n,
size_t *m_chunk_out, size_t *n_chunk_out,
size_t *total_out)
{
static int hmx_compute_chunks(size_t vtcm_total,
size_t overhead,
size_t per_n_cost,
size_t per_m_cost,
size_t per_mn_cost,
int m,
int n,
size_t m_block_cost,
size_t n_block_cost,
size_t * m_chunk_out,
size_t * n_chunk_out,
size_t * total_out) {
if (m <= 0 || n <= 0) return -1;
if (vtcm_total <= overhead) return -1;
if (per_n_cost == 0 || per_m_cost == 0 || per_mn_cost == 0) return -1;
const size_t usable = vtcm_total - overhead;
size_t best_mn = 0, best_m = 0, best_n = 0;
size_t best_cost = SIZE_MAX;
size_t best_mn = 0;
size_t best_m = 0, best_n = 0;
const size_t n_max = hex_align_down((size_t)n, HMX_FP16_TILE_N_COLS);
for (size_t nc = n_max; nc >= HMX_FP16_TILE_N_COLS; nc -= HMX_FP16_TILE_N_COLS) {
// Early exit: if nc * m_max cannot beat best, smaller nc won't either
if (nc * hex_align_down((size_t)m, HMX_FP16_TILE_N_ROWS) <= best_mn)
break;
size_t n_fixed = 0, ncmn = 0, mc_denom = 0;
if (hmx_mul_overflow(nc, per_n_cost, &n_fixed)) continue;
if (n_fixed >= usable) goto next_nc;
@@ -152,10 +164,19 @@ static int hmx_compute_chunks(
mc = hex_align_down(mc, HMX_FP16_TILE_N_ROWS);
mc = hex_smin(mc, (size_t)m);
if (mc > 0 && mc * nc > best_mn) {
best_mn = mc * nc;
best_m = mc;
best_n = nc;
if (mc == 0) {
goto next_nc;
}
size_t mblocks = ((size_t) m + mc - 1) / mc;
size_t nblocks = ((size_t) n + nc - 1) / nc;
size_t cost = mblocks * m_block_cost + nblocks * n_block_cost;
size_t mn = mc * nc;
if (cost < best_cost || (cost == best_cost && mn > best_mn)) {
best_cost = cost;
best_mn = mn;
best_m = mc;
best_n = nc;
}
}
@@ -233,7 +254,7 @@ static inline HVX_Vector dequantize_x4x2_q4_0_group_hvx(
const HVX_Vector mask_h4 = Q6_Vb_vsplat_R(0x0F);
HVX_Vector v_scales = hvx_vec_splat_f16(*scale);
// q4x4x2 stores two int4 values per byte. Keep only the selected nibble.
HVX_Vector v_quants = upper_nibbles ? Q6_Vub_vlsr_VubR(vq, 4) : vq;
HVX_Vector v_quants = Q6_Vub_vlsr_VubR(vq, 4 * upper_nibbles);
v_quants = Q6_V_vand_VV(v_quants, mask_h4);
// Shuffle before LUT
v_quants = Q6_Vb_vshuff_Vb(v_quants);
@@ -257,7 +278,7 @@ static inline void dequantize_x4x2_q4_0_x4groups_hvx(
// Load all 128 packed bytes (4 contiguous 32-byte groups)
HVX_Vector vq = hvx_vmemu(packed_128);
const HVX_Vector mask_h4 = Q6_Vb_vsplat_R(0x0F);
HVX_Vector v_quants = upper_nibbles ? Q6_Vub_vlsr_VubR(vq, 4) : vq;
HVX_Vector v_quants = Q6_Vub_vlsr_VubR(vq, 4 * upper_nibbles);
v_quants = Q6_V_vand_VV(v_quants, mask_h4);
// Shuffle before LUT
@@ -277,10 +298,8 @@ static inline void dequantize_x4x2_q4_0_x4groups_hvx(
v_hi = Q6_Vhf_equals_Vqf16(Q6_Vqf16_vmpy_VhfVhf(v_hi, v_sc23));
// Extract individual groups: scatter uses q_mask64 so only first 64 bytes matter
out[0] = v_lo; // group0 already in [0:63]
out[1] = Q6_V_vror_VR(v_lo, 64); // group1 rotated to [0:63]
out[2] = v_hi; // group2 already in [0:63]
out[3] = Q6_V_vror_VR(v_hi, 64); // group3 rotated to [0:63]
out[0] = v_lo; // group0 already in [0:63]
out[1] = v_hi; // group2 already in [0:63]
}
// Dequantize one x4x2 Q8_0 group (32 int8 quants) -> 32 FP16 in first 64 bytes.
@@ -384,8 +403,9 @@ static void dequantize_x4x2_weight_to_fp16_tiles_task(
size_t row_stride, int weight_type,
int start_tile, int end_tile) {
const int n_k_tiles = k_block / HMX_FP16_TILE_N_COLS;
const int qrow_size = (weight_type == HTP_TYPE_Q8_0) ? k_block : (k_block / 2);
const int n_k_tiles = (unsigned)k_block / HMX_FP16_TILE_N_COLS;
const bool is_q4 = (weight_type == HTP_TYPE_Q4_0 || weight_type == HTP_TYPE_IQ4_NL);
const int qrow_size = is_q4 ? ((unsigned)k_block / 2) : k_block;
const HVX_Vector vlut_cvt = (weight_type == HTP_TYPE_IQ4_NL) ? hvx_vmem(iq4_nl_to_fp16_lut) :
(weight_type == HTP_TYPE_MXFP4) ? hvx_vmem(mxfp4_to_fp16_lut) :
@@ -398,47 +418,46 @@ static void dequantize_x4x2_weight_to_fp16_tiles_task(
const HVX_Vector v_scat_step = Q6_V_vsplat_R(4); // 4 bytes = 1 column step
const HVX_VectorPred q_mask64 = Q6_Q_vsetq_R(64); // first 16 words (64 bytes)
for (int t = start_tile; t < end_tile; ) {
int ct = t / n_k_tiles; // column tile index
int kt = t % n_k_tiles; // K tile index
unsigned ct = (unsigned)start_tile / n_k_tiles; // column tile index
unsigned kt = (unsigned)start_tile % n_k_tiles; // K tile index
for (unsigned t = start_tile; t < end_tile; ) {
if (kt >= n_k_tiles) { kt = 0; ct++; }
// --- Batch-4 fast path for Q4_0/IQ4_NL: process 4 contiguous K-tiles with one vlut16 per row ---
if ((weight_type == HTP_TYPE_Q4_0 || weight_type == HTP_TYPE_IQ4_NL) && (kt % 4 == 0) && (t + 4 <= end_tile) &&
((t + 3) / n_k_tiles == ct)) {
int blk_idx = (kt * 32) / QK_Q4_0x4x2;
int sub_blk_base = ((kt * 32) % QK_Q4_0x4x2) / 32; // 0 or 4
bool upper = (sub_blk_base >= 4);
int packed_off = blk_idx * (QK_Q4_0x4x2 / 2); // 128 contiguous packed bytes
int scale_off = qrow_size + blk_idx * HMX_X4X2_DBLK_SIZE
+ sub_blk_base * (int)sizeof(__fp16); // 4 consecutive scales
// --- Batch-4 fast path for Q4: process 4 contiguous K-tiles with one vlut16 per row ---
if (is_q4 && (kt % 4 == 0) && (t + 4 <= end_tile) && ((t + 3) / n_k_tiles == ct)) {
unsigned blk_idx = (kt * 32) / QK_Q4_0x4x2;
unsigned sub_blk_base = ((kt * 32) % QK_Q4_0x4x2) / 32; // 0 or 4
bool upper = (sub_blk_base >= 4);
unsigned packed_off = blk_idx * (QK_Q4_0x4x2 / 2); // 128 contiguous packed bytes
unsigned scale_off = qrow_size + blk_idx * HMX_X4X2_DBLK_SIZE
+ sub_blk_base * (int)sizeof(__fp16); // 4 consecutive scales
__fp16 *tile_bases[4];
for (int g = 0; g < 4; g++) { tile_bases[g] = vtcm_dst + (t + g) * HMX_FP16_TILE_N_ELMS; }
for (unsigned g = 0; g < 4; g++) { tile_bases[g] = vtcm_dst + (t + g) * HMX_FP16_TILE_N_ELMS; }
HVX_Vector v_off = v_scat_base;
for (int r = 0; r < HMX_FP16_TILE_N_ROWS; r += 2) {
int row0 = ct * HMX_FP16_TILE_N_COLS + r;
int row1 = row0 + 1;
const uint8_t *r0 = vtcm_src + row0 * row_stride;
const uint8_t *r1 = vtcm_src + row1 * row_stride;
HVX_Vector v0[4], v1[4];
unsigned row_offset = ct * HMX_FP16_TILE_N_COLS * row_stride;
unsigned row1 = ct * HMX_FP16_TILE_N_COLS + 1;
for (int r = 0; r < HMX_FP16_TILE_N_ROWS; r += 2, row1 += 2) {
HVX_Vector v0[2];
const uint8_t *r0 = vtcm_src + row_offset; row_offset += row_stride;
dequantize_x4x2_q4_0_x4groups_hvx(r0 + packed_off, upper, (const __fp16 *)(r0 + scale_off), vlut_cvt, v0);
if (row1 < n_cols) {
dequantize_x4x2_q4_0_x4groups_hvx(r1 + packed_off, upper, (const __fp16 *)(r1 + scale_off), vlut_cvt, v1);
} else {
v1[0] = v1[1] = v1[2] = v1[3] = Q6_V_vzero();
}
for (int g = 0; g < 4; g++) { Q6_vscatter_QRMVwV(q_mask64, (size_t)tile_bases[g], HMX_FP16_TILE_SIZE - 1, v_off, v0[g]); }
Q6_vscatter_RMVwV((size_t)tile_bases[0], 2 * HMX_FP16_TILE_SIZE - 1, v_off, v0[0]);
Q6_vscatter_RMVwV((size_t)tile_bases[2], 2 * HMX_FP16_TILE_SIZE - 1, v_off, v0[1]);
v_off = Q6_Vw_vadd_VwVw(v_off, v_scat_step);
for (int g = 0; g < 4; g++) { Q6_vscatter_QRMVwV(q_mask64, (size_t)tile_bases[g], HMX_FP16_TILE_SIZE - 1, v_off, v1[g]); }
r0 = vtcm_src + row_offset; row_offset += row_stride;
dequantize_x4x2_q4_0_x4groups_hvx(r0 + packed_off, upper, (const __fp16 *)(r0 + scale_off), vlut_cvt, v0);
Q6_vscatter_RMVwV((size_t)tile_bases[0], 2 * HMX_FP16_TILE_SIZE - 1, v_off, v0[0]);
Q6_vscatter_RMVwV((size_t)tile_bases[2], 2 * HMX_FP16_TILE_SIZE - 1, v_off, v0[1]);
v_off = Q6_Vw_vadd_VwVw(v_off, v_scat_step);
}
for (int g = 0; g < 4; g++) { (void) *(volatile HVX_Vector *)(tile_bases[g]); }
t += 4;
t += 4; kt += 4;
continue;
}
@@ -495,20 +514,19 @@ static void dequantize_x4x2_weight_to_fp16_tiles_task(
// --- Single-tile fallback ---
__fp16 *tile_base = vtcm_dst + t * HMX_FP16_TILE_N_ELMS;
if (weight_type == HTP_TYPE_Q4_0 || weight_type == HTP_TYPE_IQ4_NL) {
int blk_idx = (kt * 32) / QK_Q4_0x4x2;
int sub_blk = ((kt * 32) % QK_Q4_0x4x2) / 32;
bool upper = (sub_blk >= 4);
int byte_off = blk_idx * (QK_Q4_0x4x2 / 2) + (upper ? (sub_blk - 4) : sub_blk) * 32;
int scale_off = qrow_size + blk_idx * HMX_X4X2_DBLK_SIZE + sub_blk * (int)sizeof(__fp16);
if (is_q4) {
unsigned blk_idx = (kt * 32) / QK_Q4_0x4x2;
unsigned sub_blk = ((kt * 32) % QK_Q4_0x4x2) / 32;
bool upper = (sub_blk >= 4);
unsigned byte_off = blk_idx * (QK_Q4_0x4x2 / 2) + (upper ? (sub_blk - 4) : sub_blk) * 32;
unsigned scale_off = qrow_size + blk_idx * HMX_X4X2_DBLK_SIZE + sub_blk * (int)sizeof(__fp16);
HVX_Vector v_off = v_scat_base; // reset to column 0
for (int r = 0; r < HMX_FP16_TILE_N_ROWS; r += 2) {
int row0 = ct * HMX_FP16_TILE_N_COLS + r;
int row1 = row0 + 1;
const uint8_t *r0 = vtcm_src + row0 * row_stride;
const uint8_t *r1 = vtcm_src + row1 * row_stride;
unsigned row_offset = ct * HMX_FP16_TILE_N_COLS * row_stride;
unsigned row1 = ct * HMX_FP16_TILE_N_COLS + 1;
for (int r = 0; r < HMX_FP16_TILE_N_ROWS; r += 2, row1 += 2) {
const uint8_t *r0 = vtcm_src + row_offset; row_offset += row_stride;
const uint8_t *r1 = vtcm_src + row_offset; row_offset += row_stride;
HVX_Vector v0 = dequantize_x4x2_q4_0_group_hvx(
r0 + byte_off, upper, (const __fp16 *)(r0 + scale_off), vlut_cvt);
@@ -585,7 +603,7 @@ static void dequantize_x4x2_weight_to_fp16_tiles_task(
}
(void) *(volatile HVX_Vector *)(tile_base);
}
++t;
++t; ++kt;
}
// Drain HVX scatter write buffer: a vmem load on the same HW thread retires
@@ -653,9 +671,13 @@ static void dequantize_x4x2_weight_chunk_to_fp16_tiles(
// --- End x4x2 dequantizers ---
// requires external HMX lock
static void core_dot_chunk_fp16(__fp16 *output, const __fp16 *activation, const __fp16 *weight, const __fp16 *scales,
static void core_dot_chunk_fp16(__fp16 *restrict output, const __fp16 *restrict activation, const __fp16 *restrict weight, const __fp16 *restrict scales,
int n_row_tiles, int n_col_tiles, int n_dot_tiles) {
hmx_set_output_scales(scales);
__builtin_assume(n_row_tiles > 0);
__builtin_assume(n_col_tiles > 0);
__builtin_assume(n_dot_tiles > 0);
Q6_bias_mxmem2_A((void *)scales);
for (int r = 0; r < n_row_tiles; ++r) {
for (int c = 0; c < n_col_tiles; ++c) {
@@ -665,16 +687,55 @@ static void core_dot_chunk_fp16(__fp16 *output, const __fp16 *activation, const
const __fp16 *col_tiles = weight + c * n_dot_tiles * HMX_FP16_TILE_N_ELMS;
for (int k = 0; k < n_dot_tiles; ++k) {
int offset = k * HMX_FP16_TILE_N_ELMS;
hmx_load_tile_pair_fp16(row_tiles + offset, col_tiles + offset);
Q6_activation_hf_mxmem_RR((unsigned int)row_tiles, 2047);
Q6_weight_hf_mxmem_RR((unsigned int)col_tiles, 2047);
row_tiles += HMX_FP16_TILE_N_ELMS;
col_tiles += HMX_FP16_TILE_N_ELMS;
}
__fp16 *out_tile = output + (r * n_col_tiles + c) * HMX_FP16_TILE_N_ELMS;
hmx_consume_accumulator_fp16(out_tile);
Q6_mxmem_AR_after_hf(out_tile, 0);
}
}
}
// --- Async HMX matmul job (for pipeline overlap) ---
typedef struct {
__fp16 * output;
const __fp16 * activation;
const __fp16 * weight;
const __fp16 * scales;
uint32_t n_row_tiles;
uint32_t n_col_tiles;
uint32_t n_dot_tiles;
} hmx_matmul_job_t;
static void hmx_matmul_worker_fn(void * data) {
hmx_matmul_job_t * job = (hmx_matmul_job_t *) data;
FARF(HIGH, "hmx-mm-job: n_row_tiles %u n_col_tiles %u n_dot_tiles %u", job->n_row_tiles, job->n_col_tiles, job->n_dot_tiles);
core_dot_chunk_fp16(job->output, job->activation, job->weight, job->scales, job->n_row_tiles, job->n_col_tiles, job->n_dot_tiles);
}
static inline void hmx_matmul_job_init(hmx_matmul_job_t * job,
__fp16 * output,
const __fp16 * activation,
const __fp16 * weight,
const __fp16 * scales,
int n_row_tiles,
int n_col_tiles,
int n_dot_tiles) {
job->output = output;
job->activation = activation;
job->weight = weight;
job->scales = scales;
job->n_row_tiles = n_row_tiles;
job->n_col_tiles = n_col_tiles;
job->n_dot_tiles = n_dot_tiles;
}
// --- End async HMX matmul job ---
static void transfer_output_chunk_fp16_to_fp32(float *restrict dst, const __fp16 *restrict vtcm_src, int n_rows, int n_cols, int n) {
assert(n_cols % HMX_FP16_TILE_N_COLS == 0);
const int n_col_tiles = n_cols / HMX_FP16_TILE_N_COLS;
@@ -832,12 +893,13 @@ int hmx_mat_mul_permuted_w16a32_batched(struct htp_context *ctx, const hmx_matmu
const size_t f32_scratch_per_m = use_dma_activation ? (size_t) params->k * sizeof(float) : 0;
size_t m_chunk_n_rows = 0, n_chunk_n_cols = 0, vtcm_used = 0;
// FP16 weight: interleave and activation load have similar per-element cost.
if (hmx_compute_chunks(vtcm_budget, /*overhead=*/256,
/*per_n=*/3 * vec_dot_size,
/*per_m=*/group_size * vec_dot_size + f32_scratch_per_m,
/*per_mn=*/sizeof(__fp16),
params->m, params->n,
&m_chunk_n_rows, &n_chunk_n_cols, &vtcm_used) != 0) {
/*per_n=*/3 * vec_dot_size,
/*per_m=*/group_size * vec_dot_size + f32_scratch_per_m,
/*per_mn=*/sizeof(__fp16), params->m, params->n,
/*m_block_cost=*/(size_t) params->n,
/*n_block_cost=*/(size_t) params->m, &m_chunk_n_rows, &n_chunk_n_cols, &vtcm_used) != 0) {
FARF(HIGH, "%s: grouped path does not fit VTCM, falling back to legacy batched loop", __func__);
return hmx_mat_mul_permuted_w16a32_batched_legacy(ctx, params);
}
@@ -1006,13 +1068,15 @@ int hmx_mat_mul_permuted_w16a32(struct htp_context *ctx, float *restrict dst, co
const size_t f32_scratch_per_m = use_dma_activation ? (size_t) k * sizeof(float) : 0;
size_t m_chunk_n_rows = 0, n_chunk_n_cols = 0, vtcm_used = 0;
// FP16 weight: interleave and activation load have similar per-element cost.
if (hmx_compute_chunks(vtcm_budget,
/*overhead=*/ 256,
/*per_n=*/ 3 * vec_dot_size, // W + S0 + S1
/*per_m=*/ vec_dot_size + f32_scratch_per_m, // A + optional F32 scratch
/*per_mn=*/ sizeof(__fp16), // O
m, n,
&m_chunk_n_rows, &n_chunk_n_cols, &vtcm_used) != 0) {
/*overhead=*/256,
/*per_n=*/3 * vec_dot_size, // W + S0 + S1
/*per_m=*/vec_dot_size + f32_scratch_per_m, // A + optional F32 scratch
/*per_mn=*/sizeof(__fp16), // O
m, n,
/*m_block_cost=*/(size_t) n,
/*n_block_cost=*/(size_t) m, &m_chunk_n_rows, &n_chunk_n_cols, &vtcm_used) != 0) {
FARF(HIGH, "%s: VTCM too small (m=%d k=%d n=%d budget=%zu)", __func__, m, k, n, vtcm_budget);
return -1;
}
@@ -1157,6 +1221,8 @@ int hmx_mat_mul_permuted_w16a32(struct htp_context *ctx, float *restrict dst, co
int mat_mul_qk_0_d16a32_out_stationary(struct htp_context *ctx, float *restrict out, const float *restrict x, const uint8_t *restrict w, int m,
int k, int n, int w_type);
#define FALLBACK_TO_STANDARD 1
int hmx_mat_mul_permuted_qk_0_d16a32(struct htp_context *ctx, float *restrict dst, const float *restrict activation,
const uint8_t *restrict permuted_weight, int m, int k, int n,
int weight_type) {
@@ -1169,9 +1235,12 @@ int hmx_mat_mul_permuted_qk_0_d16a32(struct htp_context *ctx, float *restrict ds
// for large m, k (e.g. prefill FFN Down), use out-stationary version
if (m >= 128 && k > n && n > 1024) {
FARF(MEDIUM, "hmx_matmul_qk: OUT-STATIONARY path m=%d k=%d n=%d type=%d (K_BLOCK=512, %d K-iters with fp16 intermediate)",
m, k, n, weight_type, (k + 511) / 512);
return mat_mul_qk_0_d16a32_out_stationary(ctx, dst, activation, permuted_weight, m, k, n, weight_type);
int rc = mat_mul_qk_0_d16a32_out_stationary(ctx, dst, activation, permuted_weight, m, k, n, weight_type);
if (rc != FALLBACK_TO_STANDARD) {
return rc; // 0 success, -1 error
}
FARF(MEDIUM, "hmx_matmul_qk: out-stationary fallback to standard m=%d k=%d n=%d", m, k, n);
// fall through to standard path
}
size_t row_stride = get_x4x2_row_stride(weight_type, k);
@@ -1197,9 +1266,10 @@ int hmx_mat_mul_permuted_qk_0_d16a32(struct htp_context *ctx, float *restrict ds
}
size_t m_chunk_n_rows = 0, n_chunk_n_cols = 0, vtcm_used = 0;
if (hmx_compute_chunks(vtcm_budget, /*overhead=*/256,
per_n_cost, /*per_m=*/vec_dot_size, per_mn_cost,
m, n, &m_chunk_n_rows, &n_chunk_n_cols, &vtcm_used) != 0) {
// Quantized weight: dequant ~1.5x more expensive per element than activation load.
if (hmx_compute_chunks(vtcm_budget, /*overhead=*/256, per_n_cost, /*per_m=*/vec_dot_size, per_mn_cost, m, n,
/*m_block_cost=*/(size_t) n * 3,
/*n_block_cost=*/(size_t) m * 2, &m_chunk_n_rows, &n_chunk_n_cols, &vtcm_used) != 0) {
FARF(HIGH, "%s: VTCM too small (m=%d k=%d n=%d pipe=%d budget=%zu)",
__func__, m, k, n, use_pipeline, vtcm_budget);
return -1;
@@ -1256,9 +1326,8 @@ int hmx_mat_mul_permuted_qk_0_d16a32(struct htp_context *ctx, float *restrict ds
use_pipeline ? "PIPELINE" : "SEQUENTIAL", m_chunk_n_rows, n_chunk_n_cols,
(size_t)(vtcm_ptr - (uint8_t *)ctx->vtcm_base), vtcm_budget);
HAP_compute_res_hmx_lock(ctx->vtcm_rctx);
if (!use_pipeline) {
HAP_compute_res_hmx_lock(ctx->vtcm_rctx);
for (size_t mr = 0; mr < m; mr += m_chunk_n_rows) {
// transfer activation matrix chunk into VTCM
size_t n_rows = hex_smin(m - mr, m_chunk_n_rows);
@@ -1318,20 +1387,22 @@ int hmx_mat_mul_permuted_qk_0_d16a32(struct htp_context *ctx, float *restrict ds
TIMER_STOP(output_store);
}
}
HAP_compute_res_hmx_unlock(ctx->vtcm_rctx);
} else {
// 4-stage pipeline: DMA load (A), dequantize (B), HMX matmul (C), store (D)
// stage B and D (dequantize and store) are expected to be on the critical path
// HMX compute (C) runs on dedicated worker thread, overlapping with HVX stages (B, D).
// A --> B: vtcm_qweight, 1 buffer
// B --> C: vtcm_weight0/vtcm_weight1, 2 buffers
// C --> D: vtcm_output0/vtcm_output1, 2 buffers
//
// LD ||A3| | B3 ||
// MM || C2 ||
// ST || D1 | ||
// Async timeline (C overlaps B+D):
// main+HVX: [A0][Act][B0][A1][sub C0][B1‖C0][A2][wait,sub C1][D0+B2‖C1][wait,sub C2][D1‖C2][wait][D2]
// HMX queue: [████ C0 ████████][████ C1 ████████████][████ C2 ████████]
int n_chunk_cnt = hmx_ceil_div(n, n_chunk_n_cols);
hmx_matmul_job_t job_slots[2]; // persistent double-buffered job descriptors
for (size_t mr = 0; mr < m; mr += m_chunk_n_rows) {
const size_t n_rows = hex_smin(m - mr, m_chunk_n_rows);
@@ -1352,31 +1423,34 @@ int hmx_mat_mul_permuted_qk_0_d16a32(struct htp_context *ctx, float *restrict ds
transfer_activation_chunk_threaded(ctx, vtcm_activation, activation_chunk, n_rows, k, k);
}
// prologue: B0, A1, C0, B1
// prologue: B0, A1, submit C0 (async), B1 (overlaps C0)
{
// B0
// B0: wait for DMA, dequant weight chunk 0
dma_queue_pop(ctx->dma[0]);
dequantize_x4x2_weight_chunk_to_fp16_tiles(ctx, vtcm_weight_bufs[0], vtcm_qweight, n_cols_A0, k, row_stride, weight_type);
// A1
// A1: issue DMA for weight chunk 1
const size_t n_cols_A1 = hex_smin(n - 1 * n_chunk_n_cols, n_chunk_n_cols);
if (1 < n_chunk_cnt) {
const uint8_t *qweight_chunk_A1 = permuted_weight + n_chunk_n_cols * row_stride;
dma_queue_push(ctx->dma[0], dma_make_ptr(vtcm_qweight, qweight_chunk_A1), row_stride, row_stride, row_stride, n_cols_A1);
}
// C0
core_dot_chunk_fp16((__fp16 *) vtcm_output_bufs[0], (__fp16 *) vtcm_activation, (__fp16 *) vtcm_weight_bufs[0], vtcm_scales,
hmx_ceil_div(n_rows, HMX_FP16_TILE_N_ROWS), hmx_ceil_div(n_cols_A0, HMX_FP16_TILE_N_COLS), k / HMX_FP16_TILE_N_ROWS);
// submit C0 (non-blocking — HMX worker executes in parallel)
hmx_matmul_job_init(&job_slots[0], (__fp16 *) vtcm_output_bufs[0], (__fp16 *) vtcm_activation,
(__fp16 *) vtcm_weight_bufs[0], vtcm_scales,
hmx_ceil_div(n_rows, HMX_FP16_TILE_N_ROWS),
hmx_ceil_div(n_cols_A0, HMX_FP16_TILE_N_COLS), k / HMX_FP16_TILE_N_ROWS);
hmx_queue_push(ctx->hmx_queue, hmx_queue_make_desc(hmx_matmul_worker_fn, &job_slots[0]));
// B1
// B1: DMA pop + dequant (runs in parallel with C0 on HMX worker)
if (1 < n_chunk_cnt) {
dma_queue_pop(ctx->dma[0]);
dequantize_x4x2_weight_chunk_to_fp16_tiles(ctx, vtcm_weight_bufs[1], vtcm_qweight, n_cols_A1, k, row_stride, weight_type);
}
}
// main loop
// main loop: wait C_i → submit C_{i+1} → D_i + B_{i+2} (parallel with C_{i+1})
for (int i = 0; i < n_chunk_cnt; ++i) {
const size_t nc = i * n_chunk_n_cols;
const size_t nc_p1 = nc + 1 * n_chunk_n_cols;
@@ -1386,36 +1460,41 @@ int hmx_mat_mul_permuted_qk_0_d16a32(struct htp_context *ctx, float *restrict ds
const size_t n_cols_p1 = hex_smin(n - nc_p1, n_chunk_n_cols);
const size_t n_cols_p2 = hex_smin(n - nc_p2, n_chunk_n_cols);
// issue A_{i+2}
// issue A_{i+2}: DMA push (non-blocking)
if (i + 2 < n_chunk_cnt) {
const uint8_t *qweight_chunk_p2 = permuted_weight + nc_p2 * row_stride;
dma_queue_push(ctx->dma[0], dma_make_ptr(vtcm_qweight, qweight_chunk_p2), row_stride, row_stride, row_stride, n_cols_p2);
}
// wait for HMX (C_{i}) -- C_{i} is done
// wait C_i: block until prologue/previous C completes
hmx_queue_pop(ctx->hmx_queue);
// result of B_{i+1} (input of C_{i+1}) should be ready now
// issue C_{i+1}
// submit C_{i+1} (non-blocking, overlaps with D_i + B_{i+2} below)
// job_slots[(i+1)%2] is safe: C_i just completed, freeing slot i%2's
// counterpart — and (i+1)%2 was last used by C_{i-1} which completed
// before C_i was submitted.
if (i + 1 < n_chunk_cnt) {
core_dot_chunk_fp16((__fp16 *) vtcm_output_bufs[(i + 1) % 2], (__fp16 *) vtcm_activation, (__fp16 *) vtcm_weight_bufs[(i + 1) % 2], vtcm_scales,
hmx_ceil_div(n_rows, HMX_FP16_TILE_N_ROWS), hmx_ceil_div(n_cols_p1, HMX_FP16_TILE_N_COLS), k / HMX_FP16_TILE_N_ROWS);
hmx_matmul_job_init(&job_slots[(i + 1) % 2], (__fp16 *) vtcm_output_bufs[(i + 1) % 2],
(__fp16 *) vtcm_activation, (__fp16 *) vtcm_weight_bufs[(i + 1) % 2],
vtcm_scales, hmx_ceil_div(n_rows, HMX_FP16_TILE_N_ROWS),
hmx_ceil_div(n_cols_p1, HMX_FP16_TILE_N_COLS), k / HMX_FP16_TILE_N_ROWS);
hmx_queue_push(ctx->hmx_queue, hmx_queue_make_desc(hmx_matmul_worker_fn, &job_slots[(i + 1) % 2]));
}
// compute D_{i}
// D_i: store output (multi-thread HVX, parallel with C_{i+1})
float *output_chunk = dst + (mr * n + nc);
transfer_output_chunk_threaded(ctx, output_chunk, vtcm_output_bufs[i % 2], n_rows, n_cols, n);
// wait for DMA (A_{i+2}), compute B_{i+2}
// B_{i+2}: DMA pop + dequant (multi-thread HVX, parallel with C_{i+1})
if (i + 2 < n_chunk_cnt) {
dma_queue_pop(ctx->dma[0]);
dequantize_x4x2_weight_chunk_to_fp16_tiles(ctx, vtcm_weight_bufs[(i + 2) % 2], vtcm_qweight, n_cols_p2, k, row_stride, weight_type);
}
}
}
}
HAP_compute_res_hmx_unlock(ctx->vtcm_rctx);
hmx_queue_suspend(ctx->hmx_queue);
}
TIMER_STOP(total);
@@ -1434,10 +1513,13 @@ int hmx_mat_mul_permuted_qk_0_d16a32(struct htp_context *ctx, float *restrict ds
}
// C += AB
void core_mma_chunk_fp16(__fp16 *c, const __fp16 *a, const __fp16 *b, const __fp16 *col_scales, const __fp16 *eye_tile,
void core_mma_chunk_fp16(__fp16 *restrict c, const __fp16 *restrict a, const __fp16 *restrict b, const __fp16 *restrict col_scales, const __fp16 *restrict eye_tile,
int n_row_tiles, int n_col_tiles, int n_dot_tiles, bool zero_init) {
__builtin_assume(n_row_tiles > 0);
__builtin_assume(n_col_tiles > 0);
__builtin_assume(n_dot_tiles > 0);
hmx_set_output_scales(col_scales);
Q6_bias_mxmem2_A((void *)col_scales);
for (int i = 0; i < n_row_tiles; ++i) {
for (int j = 0; j < n_col_tiles; ++j) {
@@ -1448,15 +1530,17 @@ void core_mma_chunk_fp16(__fp16 *c, const __fp16 *a, const __fp16 *b, const __fp
__fp16 *accum_tile = c + (i * n_col_tiles + j) * HMX_FP16_TILE_N_ELMS;
if (!zero_init) {
hmx_load_tile_pair_fp16(accum_tile, eye_tile);
Q6_activation_hf_mxmem_RR((unsigned int)accum_tile, 2047);
Q6_weight_hf_mxmem_RR((unsigned int)eye_tile, 2047);
}
for (int k = 0; k < n_dot_tiles; ++k) {
int offset = k * HMX_FP16_TILE_N_ELMS;
hmx_load_tile_pair_fp16(row_tiles + offset, col_tiles + offset);
Q6_activation_hf_mxmem_RR((unsigned int)row_tiles, 2047);
Q6_weight_hf_mxmem_RR((unsigned int)col_tiles, 2047);
row_tiles += HMX_FP16_TILE_N_ELMS;
col_tiles += HMX_FP16_TILE_N_ELMS;
}
hmx_consume_accumulator_fp16(accum_tile);
Q6_mxmem_AR_after_hf(accum_tile, 0);
}
}
}
@@ -1540,12 +1624,41 @@ int mat_mul_qk_0_d16a32_out_stationary(struct htp_context *ctx, float *restrict
const size_t vtcm_budget = ctx->vtcm_size;
const size_t M_BLOCK_SIZE = 512;
const size_t N_BLOCK_SIZE = 512;
const size_t K_BLOCK_SIZE = 512;
const size_t K_BLOCK_SIZE = 1024;
// Compute precise buffer sizes
// Fallback: if k doesn't need K-blocking, out-stationary has no advantage
const size_t k_iters_check = (k + K_BLOCK_SIZE - 1) / K_BLOCK_SIZE;
if (k_iters_check <= 1) {
FARF(MEDIUM, "%s: K_BLK=%zu >= k=%d, fallback to standard path", __func__, K_BLOCK_SIZE, k);
return FALLBACK_TO_STANDARD;
}
// Dynamic M,N search via hmx_compute_chunks
const size_t sub_row_stride_alloc = get_x4x2_row_stride(weight_type, K_BLOCK_SIZE);
const size_t per_m = K_BLOCK_SIZE * sizeof(float) // scratch1: M×K×4 (act DMA staging F32)
+ K_BLOCK_SIZE * sizeof(__fp16); // activation: M×K×2 (F16 tiles)
const size_t per_n = sub_row_stride_alloc // scratch0: N×sub_row(K) (packed quant)
+ K_BLOCK_SIZE * sizeof(__fp16); // weight: N×K×2 (F16 tiles)
const size_t per_mn = sizeof(__fp16); // output: M×N×2 (out-stationary)
// Alignment margin: hex_align_up can add up to 2047 bytes per buffer;
// scratch1 (mc×6144) is naturally 2048-aligned, remaining 4 buffers need margin
const size_t align_margin = 4 * HMX_FP16_TILE_SIZE;
const size_t overhead = HMX_FP16_TILE_SIZE + 256 + align_margin; // eye_tile + scales + alignment
size_t M_BLOCK_SIZE, N_BLOCK_SIZE, vtcm_used;
// Cost-based search: minimize ceil(m/mc)*m_block_cost + ceil(n/nc)*n_block_cost.
// From profiling: wt_dequant per element ≈ 1.5× activation load per element.
// m_block_cost = n*3: each extra M-block re-dequants all N×K weight (expensive).
// n_block_cost = m*2: each extra N-block re-loads all M×K activation (cheaper).
const size_t m_block_cost = (size_t) n * 3;
const size_t n_block_cost = (size_t) m * 2;
if (hmx_compute_chunks(vtcm_budget, overhead, per_n, per_m, per_mn, m, n, m_block_cost, n_block_cost, &M_BLOCK_SIZE,
&N_BLOCK_SIZE, &vtcm_used) != 0) {
FARF(HIGH, "%s: VTCM too small (m=%d k=%d n=%d budget=%zu)", __func__, m, k, n, vtcm_budget);
return -1;
}
// Compute precise buffer sizes from searched M,N and fixed K
const size_t weight_size = hex_align_up(N_BLOCK_SIZE * K_BLOCK_SIZE * sizeof(__fp16), HMX_FP16_TILE_SIZE);
const size_t act_size = hex_align_up(M_BLOCK_SIZE * K_BLOCK_SIZE * sizeof(__fp16), HMX_FP16_TILE_SIZE);
const size_t out_size = hex_align_up(M_BLOCK_SIZE * N_BLOCK_SIZE * sizeof(__fp16), HMX_FP16_TILE_SIZE);
@@ -1554,7 +1667,8 @@ int mat_mul_qk_0_d16a32_out_stationary(struct htp_context *ctx, float *restrict
const size_t total_vtcm = weight_size + act_size + out_size + scratch0_sz + scratch1_sz + HMX_FP16_TILE_SIZE + 256;
if (total_vtcm > vtcm_budget) {
FARF(HIGH, "%s: VTCM too small: need %zu have %zu (m=%d k=%d n=%d)", __func__, total_vtcm, vtcm_budget, m, k, n);
FARF(HIGH, "%s: VTCM overflow after search: need %zu have %zu (M=%zu N=%zu K=%zu)", __func__, total_vtcm,
vtcm_budget, M_BLOCK_SIZE, N_BLOCK_SIZE, K_BLOCK_SIZE);
return -1;
}
@@ -1568,8 +1682,8 @@ int mat_mul_qk_0_d16a32_out_stationary(struct htp_context *ctx, float *restrict
__fp16 *vtcm_scales = (__fp16 *) vtcm_seq_alloc(&vtcm_ptr, 256);
assert((size_t)(vtcm_ptr - (uint8_t *)ctx->vtcm_base) <= vtcm_budget);
FARF(MEDIUM, "%s: m=%d k=%d n=%d wtype=%d vtcm=%zu/%zu", __func__, m, k, n, weight_type,
(size_t)(vtcm_ptr - (uint8_t *)ctx->vtcm_base), vtcm_budget);
FARF(HIGH, "hmx-mm: m=%d k=%d n=%d wtype=%d block M=%zu N=%zu K=%zu vtcm=%zu/%zu", __func__, m, k, n, weight_type,
M_BLOCK_SIZE, N_BLOCK_SIZE, K_BLOCK_SIZE, (size_t) (vtcm_ptr - (uint8_t *) ctx->vtcm_base), vtcm_budget);
// initialize eye tile (32x32 identity matrix)
{