drivers/raw/ioat/rte_idxd_rawdev_fns.h

   1 /* SPDX-License-Identifier: BSD-3-Clause
   2  * Copyright(c) 2021 Intel Corporation
   3  */
   4 #ifndef _RTE_IDXD_RAWDEV_FNS_H_
   5 #define _RTE_IDXD_RAWDEV_FNS_H_
   6
   7 /**
   8  * @file
   9  * This header file contains the implementation of the various ioat
  10  * rawdev functions for DSA hardware. The API specification and key
  11  * public structures are defined in "rte_ioat_rawdev.h".
  12  *
  13  * This file should not be included directly, but instead applications should
  14  * include "rte_ioat_rawdev.h", which then includes this file - and the
  15  * IOAT/CBDMA equivalent header - in turn.
  16  */
  17
  18 #include <stdint.h>
  19
  20 /*
  21  * Defines used in the data path for interacting with IDXD hardware.
  22  */
  23 #define IDXD_CMD_OP_SHIFT 24
  24 enum rte_idxd_ops {
  25         idxd_op_nop = 0,
  26         idxd_op_batch,
  27         idxd_op_drain,
  28         idxd_op_memmove,
  29         idxd_op_fill
  30 };
  31
  32 #define IDXD_FLAG_FENCE                 (1 << 0)
  33 #define IDXD_FLAG_COMPLETION_ADDR_VALID (1 << 2)
  34 #define IDXD_FLAG_REQUEST_COMPLETION    (1 << 3)
  35 #define IDXD_FLAG_CACHE_CONTROL         (1 << 8)
  36
  37 #define IOAT_COMP_UPDATE_SHIFT  3
  38 #define IOAT_CMD_OP_SHIFT       24
  39 enum rte_ioat_ops {
  40         ioat_op_copy = 0,       /* Standard DMA Operation */
  41         ioat_op_fill            /* Block Fill */
  42 };
  43
  44 /**
  45  * Hardware descriptor used by DSA hardware, for both bursts and
  46  * for individual operations.
  47  */
  48 struct rte_idxd_hw_desc {
  49         uint32_t pasid;
  50         uint32_t op_flags;
  51         rte_iova_t completion;
  52
  53         RTE_STD_C11
  54         union {
  55                 rte_iova_t src;      /* source address for copy ops etc. */
  56                 rte_iova_t desc_addr; /* descriptor pointer for batch */
  57         };
  58         rte_iova_t dst;
  59
  60         uint32_t size;    /* length of data for op, or batch size */
  61
  62         uint16_t intr_handle; /* completion interrupt handle */
  63
  64         /* remaining 26 bytes are reserved */
  65         uint16_t __reserved[13];
  66 } __rte_aligned(64);
  67
  68 /**
  69  * Completion record structure written back by DSA
  70  */
  71 struct rte_idxd_completion {
  72         uint8_t status;
  73         uint8_t result;
  74         /* 16-bits pad here */
  75         uint32_t completed_size; /* data length, or descriptors for batch */
  76
  77         rte_iova_t fault_address;
  78         uint32_t invalid_flags;
  79 } __rte_aligned(32);
  80
  81 /**
  82  * structure used to save the "handles" provided by the user to be
  83  * returned to the user on job completion.
  84  */
  85 struct rte_idxd_user_hdl {
  86         uint64_t src;
  87         uint64_t dst;
  88 };
  89
  90 /**
  91  * @internal
  92  * Structure representing an IDXD device instance
  93  */
  94 struct rte_idxd_rawdev {
  95         enum rte_ioat_dev_type type;
  96         struct rte_ioat_xstats xstats;
  97
  98         void *portal; /* address to write the batch descriptor */
  99
 100         struct rte_ioat_rawdev_config cfg;
 101         rte_iova_t desc_iova; /* base address of desc ring, needed for completions */
 102
 103         /* counters to track the batches */
 104         unsigned short max_batches;
 105         unsigned short batch_idx_read;
 106         unsigned short batch_idx_write;
 107         unsigned short *batch_idx_ring; /* store where each batch ends */
 108
 109         /* track descriptors and handles */
 110         unsigned short desc_ring_mask;
 111         unsigned short hdls_avail; /* handles for ops completed */
 112         unsigned short hdls_read; /* the read pointer for hdls/desc rings */
 113         unsigned short batch_start; /* start+size == write pointer for hdls/desc */
 114         unsigned short batch_size;
 115
 116         struct rte_idxd_hw_desc *desc_ring;
 117         struct rte_idxd_user_hdl *hdl_ring;
 118         /* flags to indicate handle validity. Kept separate from ring, to avoid
 119          * using 8 bytes per flag. Upper 8 bits holds error code if any.
 120          */
 121         uint16_t *hdl_ring_flags;
 122 };
 123
 124 #define RTE_IDXD_HDL_NORMAL     0
 125 #define RTE_IDXD_HDL_INVALID    (1 << 0) /* no handle stored for this element */
 126 #define RTE_IDXD_HDL_OP_FAILED  (1 << 1) /* return failure for this one */
 127 #define RTE_IDXD_HDL_OP_SKIPPED (1 << 2) /* this op was skipped */
 128
 129 static __rte_always_inline uint16_t
 130 __idxd_burst_capacity(int dev_id)
 131 {
 132         struct rte_idxd_rawdev *idxd =
 133                         (struct rte_idxd_rawdev *)rte_rawdevs[dev_id].dev_private;
 134         uint16_t write_idx = idxd->batch_start + idxd->batch_size;
 135         uint16_t used_space;
 136
 137         /* Check for space in the batch ring */
 138         if ((idxd->batch_idx_read == 0 && idxd->batch_idx_write == idxd->max_batches) ||
 139                         idxd->batch_idx_write + 1 == idxd->batch_idx_read)
 140                 return 0;
 141
 142         /* for descriptors, check for wrap-around on write but not read */
 143         if (idxd->hdls_read > write_idx)
 144                 write_idx += idxd->desc_ring_mask + 1;
 145         used_space = write_idx - idxd->hdls_read;
 146
 147         /* Return amount of free space in the descriptor ring
 148          * subtract 1 for space for batch descriptor and 1 for possible null desc
 149          */
 150         return idxd->desc_ring_mask - used_space - 2;
 151 }
 152
 153 static __rte_always_inline rte_iova_t
 154 __desc_idx_to_iova(struct rte_idxd_rawdev *idxd, uint16_t n)
 155 {
 156         return idxd->desc_iova + (n * sizeof(struct rte_idxd_hw_desc));
 157 }
 158
 159 static __rte_always_inline int
 160 __idxd_write_desc(int dev_id,
 161                 const uint32_t op_flags,
 162                 const rte_iova_t src,
 163                 const rte_iova_t dst,
 164                 const uint32_t size,
 165                 const struct rte_idxd_user_hdl *hdl)
 166 {
 167         struct rte_idxd_rawdev *idxd =
 168                         (struct rte_idxd_rawdev *)rte_rawdevs[dev_id].dev_private;
 169         uint16_t write_idx = idxd->batch_start + idxd->batch_size;
 170         uint16_t mask = idxd->desc_ring_mask;
 171
 172         /* first check batch ring space then desc ring space */
 173         if ((idxd->batch_idx_read == 0 && idxd->batch_idx_write == idxd->max_batches) ||
 174                         idxd->batch_idx_write + 1 == idxd->batch_idx_read)
 175                 goto failed;
 176         /* for descriptor ring, we always need a slot for batch completion */
 177         if (((write_idx + 2) & mask) == idxd->hdls_read)
 178                 goto failed;
 179
 180         /* write desc and handle. Note, descriptors don't wrap */
 181         idxd->desc_ring[write_idx].pasid = 0;
 182         idxd->desc_ring[write_idx].op_flags = op_flags | IDXD_FLAG_COMPLETION_ADDR_VALID;
 183         idxd->desc_ring[write_idx].completion = __desc_idx_to_iova(idxd, write_idx & mask);
 184         idxd->desc_ring[write_idx].src = src;
 185         idxd->desc_ring[write_idx].dst = dst;
 186         idxd->desc_ring[write_idx].size = size;
 187
 188         if (hdl == NULL)
 189                 idxd->hdl_ring_flags[write_idx & mask] = RTE_IDXD_HDL_INVALID;
 190         else
 191                 idxd->hdl_ring[write_idx & mask] = *hdl;
 192         idxd->batch_size++;
 193
 194         idxd->xstats.enqueued++;
 195
 196         rte_prefetch0_write(&idxd->desc_ring[write_idx + 1]);
 197         return 1;
 198
 199 failed:
 200         idxd->xstats.enqueue_failed++;
 201         rte_errno = ENOSPC;
 202         return 0;
 203 }
 204
 205 static __rte_always_inline int
 206 __idxd_enqueue_fill(int dev_id, uint64_t pattern, rte_iova_t dst,
 207                 unsigned int length, uintptr_t dst_hdl)
 208 {
 209         const struct rte_idxd_user_hdl hdl = {
 210                         .dst = dst_hdl
 211         };
 212         return __idxd_write_desc(dev_id,
 213                         (idxd_op_fill << IDXD_CMD_OP_SHIFT) | IDXD_FLAG_CACHE_CONTROL,
 214                         pattern, dst, length, &hdl);
 215 }
 216
 217 static __rte_always_inline int
 218 __idxd_enqueue_copy(int dev_id, rte_iova_t src, rte_iova_t dst,
 219                 unsigned int length, uintptr_t src_hdl, uintptr_t dst_hdl)
 220 {
 221         const struct rte_idxd_user_hdl hdl = {
 222                         .src = src_hdl,
 223                         .dst = dst_hdl
 224         };
 225         return __idxd_write_desc(dev_id,
 226                         (idxd_op_memmove << IDXD_CMD_OP_SHIFT) | IDXD_FLAG_CACHE_CONTROL,
 227                         src, dst, length, &hdl);
 228 }
 229
 230 static __rte_always_inline int
 231 __idxd_fence(int dev_id)
 232 {
 233         /* only op field needs filling - zero src, dst and length */
 234         return __idxd_write_desc(dev_id, IDXD_FLAG_FENCE, 0, 0, 0, NULL);
 235 }
 236
 237 static __rte_always_inline void
 238 __idxd_movdir64b(volatile void *dst, const struct rte_idxd_hw_desc *src)
 239 {
 240         asm volatile (".byte 0x66, 0x0f, 0x38, 0xf8, 0x02"
 241                         :
 242                         : "a" (dst), "d" (src)
 243                         : "memory");
 244 }
 245
 246 static __rte_always_inline int
 247 __idxd_perform_ops(int dev_id)
 248 {
 249         struct rte_idxd_rawdev *idxd =
 250                         (struct rte_idxd_rawdev *)rte_rawdevs[dev_id].dev_private;
 251
 252         if (!idxd->cfg.no_prefetch_completions)
 253                 rte_prefetch1(&idxd->desc_ring[idxd->batch_idx_ring[idxd->batch_idx_read]]);
 254
 255         if (idxd->batch_size == 0)
 256                 return 0;
 257
 258         if (idxd->batch_size == 1)
 259                 /* use a fence as a null descriptor, so batch_size >= 2 */
 260                 if (__idxd_fence(dev_id) != 1)
 261                         return -1;
 262
 263         /* write completion beyond last desc in the batch */
 264         uint16_t comp_idx = (idxd->batch_start + idxd->batch_size) & idxd->desc_ring_mask;
 265         *((uint64_t *)&idxd->desc_ring[comp_idx]) = 0; /* zero start of desc */
 266         idxd->hdl_ring_flags[comp_idx] = RTE_IDXD_HDL_INVALID;
 267
 268         const struct rte_idxd_hw_desc batch_desc = {
 269                         .op_flags = (idxd_op_batch << IDXD_CMD_OP_SHIFT) |
 270                                 IDXD_FLAG_COMPLETION_ADDR_VALID |
 271                                 IDXD_FLAG_REQUEST_COMPLETION,
 272                         .desc_addr = __desc_idx_to_iova(idxd, idxd->batch_start),
 273                         .completion = __desc_idx_to_iova(idxd, comp_idx),
 274                         .size = idxd->batch_size,
 275         };
 276
 277         _mm_sfence(); /* fence before writing desc to device */
 278         __idxd_movdir64b(idxd->portal, &batch_desc);
 279         idxd->xstats.started += idxd->batch_size;
 280
 281         idxd->batch_start += idxd->batch_size + 1;
 282         idxd->batch_start &= idxd->desc_ring_mask;
 283         idxd->batch_size = 0;
 284
 285         idxd->batch_idx_ring[idxd->batch_idx_write++] = comp_idx;
 286         if (idxd->batch_idx_write > idxd->max_batches)
 287                 idxd->batch_idx_write = 0;
 288
 289         return 0;
 290 }
 291
 292 static __rte_always_inline int
 293 __idxd_completed_ops(int dev_id, uint8_t max_ops, uint32_t *status, uint8_t *num_unsuccessful,
 294                 uintptr_t *src_hdls, uintptr_t *dst_hdls)
 295 {
 296         struct rte_idxd_rawdev *idxd =
 297                         (struct rte_idxd_rawdev *)rte_rawdevs[dev_id].dev_private;
 298         unsigned short n, h_idx;
 299
 300         while (idxd->batch_idx_read != idxd->batch_idx_write) {
 301                 uint16_t idx_to_chk = idxd->batch_idx_ring[idxd->batch_idx_read];
 302                 volatile struct rte_idxd_completion *comp_to_chk =
 303                                 (struct rte_idxd_completion *)&idxd->desc_ring[idx_to_chk];
 304                 uint8_t batch_status = comp_to_chk->status;
 305                 if (batch_status == 0)
 306                         break;
 307                 comp_to_chk->status = 0;
 308                 if (unlikely(batch_status > 1)) {
 309                         /* error occurred somewhere in batch, start where last checked */
 310                         uint16_t desc_count = comp_to_chk->completed_size;
 311                         uint16_t batch_start = idxd->hdls_avail;
 312                         uint16_t batch_end = idx_to_chk;
 313
 314                         if (batch_start > batch_end)
 315                                 batch_end += idxd->desc_ring_mask + 1;
 316                         /* go through each batch entry and see status */
 317                         for (n = 0; n < desc_count; n++) {
 318                                 uint16_t idx = (batch_start + n) & idxd->desc_ring_mask;
 319                                 volatile struct rte_idxd_completion *comp =
 320                                         (struct rte_idxd_completion *)&idxd->desc_ring[idx];
 321                                 if (comp->status != 0 &&
 322                                                 idxd->hdl_ring_flags[idx] == RTE_IDXD_HDL_NORMAL) {
 323                                         idxd->hdl_ring_flags[idx] = RTE_IDXD_HDL_OP_FAILED;
 324                                         idxd->hdl_ring_flags[idx] |= (comp->status << 8);
 325                                         comp->status = 0; /* clear error for next time */
 326                                 }
 327                         }
 328                         /* if batch is incomplete, mark rest as skipped */
 329                         for ( ; n < batch_end - batch_start; n++) {
 330                                 uint16_t idx = (batch_start + n) & idxd->desc_ring_mask;
 331                                 if (idxd->hdl_ring_flags[idx] == RTE_IDXD_HDL_NORMAL)
 332                                         idxd->hdl_ring_flags[idx] = RTE_IDXD_HDL_OP_SKIPPED;
 333                         }
 334                 }
 335                 /* avail points to one after the last one written */
 336                 idxd->hdls_avail = (idx_to_chk + 1) & idxd->desc_ring_mask;
 337                 idxd->batch_idx_read++;
 338                 if (idxd->batch_idx_read > idxd->max_batches)
 339                         idxd->batch_idx_read = 0;
 340         }
 341
 342         if (idxd->cfg.hdls_disable && status == NULL) {
 343                 n = (idxd->hdls_avail < idxd->hdls_read) ?
 344                                 (idxd->hdls_avail + idxd->desc_ring_mask + 1 - idxd->hdls_read) :
 345                                 (idxd->hdls_avail - idxd->hdls_read);
 346                 idxd->hdls_read = idxd->hdls_avail;
 347                 goto out;
 348         }
 349
 350         n = 0;
 351         h_idx = idxd->hdls_read;
 352         while (h_idx != idxd->hdls_avail) {
 353                 uint16_t flag = idxd->hdl_ring_flags[h_idx];
 354                 if (flag != RTE_IDXD_HDL_INVALID) {
 355                         if (!idxd->cfg.hdls_disable) {
 356                                 src_hdls[n] = idxd->hdl_ring[h_idx].src;
 357                                 dst_hdls[n] = idxd->hdl_ring[h_idx].dst;
 358                         }
 359                         if (unlikely(flag != RTE_IDXD_HDL_NORMAL)) {
 360                                 if (status != NULL)
 361                                         status[n] = flag == RTE_IDXD_HDL_OP_SKIPPED ?
 362                                                         RTE_IOAT_OP_SKIPPED :
 363                                                         /* failure case, return err code */
 364                                                         idxd->hdl_ring_flags[h_idx] >> 8;
 365                                 if (num_unsuccessful != NULL)
 366                                         *num_unsuccessful += 1;
 367                         }
 368                         n++;
 369                 }
 370                 idxd->hdl_ring_flags[h_idx] = RTE_IDXD_HDL_NORMAL;
 371                 if (++h_idx > idxd->desc_ring_mask)
 372                         h_idx = 0;
 373                 if (n >= max_ops)
 374                         break;
 375         }
 376
 377         /* skip over any remaining blank elements, e.g. batch completion */
 378         while (idxd->hdl_ring_flags[h_idx] == RTE_IDXD_HDL_INVALID && h_idx != idxd->hdls_avail) {
 379                 idxd->hdl_ring_flags[h_idx] = RTE_IDXD_HDL_NORMAL;
 380                 if (++h_idx > idxd->desc_ring_mask)
 381                         h_idx = 0;
 382         }
 383         idxd->hdls_read = h_idx;
 384
 385 out:
 386         idxd->xstats.completed += n;
 387         return n;
 388 }
 389
 390 #endif