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 };
 119
 120 static __rte_always_inline uint16_t
 121 __idxd_burst_capacity(int dev_id)
 122 {
 123         struct rte_idxd_rawdev *idxd =
 124                         (struct rte_idxd_rawdev *)rte_rawdevs[dev_id].dev_private;
 125         uint16_t write_idx = idxd->batch_start + idxd->batch_size;
 126         uint16_t used_space;
 127
 128         /* Check for space in the batch ring */
 129         if ((idxd->batch_idx_read == 0 && idxd->batch_idx_write == idxd->max_batches) ||
 130                         idxd->batch_idx_write + 1 == idxd->batch_idx_read)
 131                 return 0;
 132
 133         /* for descriptors, check for wrap-around on write but not read */
 134         if (idxd->hdls_read > write_idx)
 135                 write_idx += idxd->desc_ring_mask + 1;
 136         used_space = write_idx - idxd->hdls_read;
 137
 138         /* Return amount of free space in the descriptor ring */
 139         return idxd->desc_ring_mask - used_space;
 140 }
 141
 142 static __rte_always_inline rte_iova_t
 143 __desc_idx_to_iova(struct rte_idxd_rawdev *idxd, uint16_t n)
 144 {
 145         return idxd->desc_iova + (n * sizeof(struct rte_idxd_hw_desc));
 146 }
 147
 148 static __rte_always_inline int
 149 __idxd_write_desc(int dev_id,
 150                 const uint32_t op_flags,
 151                 const rte_iova_t src,
 152                 const rte_iova_t dst,
 153                 const uint32_t size,
 154                 const struct rte_idxd_user_hdl *hdl)
 155 {
 156         struct rte_idxd_rawdev *idxd =
 157                         (struct rte_idxd_rawdev *)rte_rawdevs[dev_id].dev_private;
 158         uint16_t write_idx = idxd->batch_start + idxd->batch_size;
 159
 160         /* first check batch ring space then desc ring space */
 161         if ((idxd->batch_idx_read == 0 && idxd->batch_idx_write == idxd->max_batches) ||
 162                         idxd->batch_idx_write + 1 == idxd->batch_idx_read)
 163                 goto failed;
 164         if (((write_idx + 1) & idxd->desc_ring_mask) == idxd->hdls_read)
 165                 goto failed;
 166
 167         /* write desc and handle. Note, descriptors don't wrap */
 168         idxd->desc_ring[write_idx].pasid = 0;
 169         idxd->desc_ring[write_idx].op_flags = op_flags | IDXD_FLAG_COMPLETION_ADDR_VALID;
 170         idxd->desc_ring[write_idx].completion = __desc_idx_to_iova(idxd, write_idx);
 171         idxd->desc_ring[write_idx].src = src;
 172         idxd->desc_ring[write_idx].dst = dst;
 173         idxd->desc_ring[write_idx].size = size;
 174
 175         idxd->hdl_ring[write_idx & idxd->desc_ring_mask] = *hdl;
 176         idxd->batch_size++;
 177
 178         idxd->xstats.enqueued++;
 179
 180         rte_prefetch0_write(&idxd->desc_ring[write_idx + 1]);
 181         return 1;
 182
 183 failed:
 184         idxd->xstats.enqueue_failed++;
 185         rte_errno = ENOSPC;
 186         return 0;
 187 }
 188
 189 static __rte_always_inline int
 190 __idxd_enqueue_fill(int dev_id, uint64_t pattern, rte_iova_t dst,
 191                 unsigned int length, uintptr_t dst_hdl)
 192 {
 193         const struct rte_idxd_user_hdl hdl = {
 194                         .dst = dst_hdl
 195         };
 196         return __idxd_write_desc(dev_id,
 197                         (idxd_op_fill << IDXD_CMD_OP_SHIFT) | IDXD_FLAG_CACHE_CONTROL,
 198                         pattern, dst, length, &hdl);
 199 }
 200
 201 static __rte_always_inline int
 202 __idxd_enqueue_copy(int dev_id, rte_iova_t src, rte_iova_t dst,
 203                 unsigned int length, uintptr_t src_hdl, uintptr_t dst_hdl)
 204 {
 205         const struct rte_idxd_user_hdl hdl = {
 206                         .src = src_hdl,
 207                         .dst = dst_hdl
 208         };
 209         return __idxd_write_desc(dev_id,
 210                         (idxd_op_memmove << IDXD_CMD_OP_SHIFT) | IDXD_FLAG_CACHE_CONTROL,
 211                         src, dst, length, &hdl);
 212 }
 213
 214 static __rte_always_inline int
 215 __idxd_fence(int dev_id)
 216 {
 217         static const struct rte_idxd_user_hdl null_hdl;
 218         /* only op field needs filling - zero src, dst and length */
 219         return __idxd_write_desc(dev_id, IDXD_FLAG_FENCE, 0, 0, 0, &null_hdl);
 220 }
 221
 222 static __rte_always_inline void
 223 __idxd_movdir64b(volatile void *dst, const struct rte_idxd_hw_desc *src)
 224 {
 225         asm volatile (".byte 0x66, 0x0f, 0x38, 0xf8, 0x02"
 226                         :
 227                         : "a" (dst), "d" (src)
 228                         : "memory");
 229 }
 230
 231 static __rte_always_inline int
 232 __idxd_perform_ops(int dev_id)
 233 {
 234         struct rte_idxd_rawdev *idxd =
 235                         (struct rte_idxd_rawdev *)rte_rawdevs[dev_id].dev_private;
 236         /* write completion to last desc in the batch */
 237         uint16_t comp_idx = idxd->batch_start + idxd->batch_size - 1;
 238         if (comp_idx > idxd->desc_ring_mask) {
 239                 comp_idx &= idxd->desc_ring_mask;
 240                 *((uint64_t *)&idxd->desc_ring[comp_idx]) = 0; /* zero start of desc */
 241         }
 242
 243         if (idxd->batch_size == 0)
 244                 return 0;
 245
 246         _mm_sfence(); /* fence before writing desc to device */
 247         if (idxd->batch_size > 1) {
 248                 struct rte_idxd_hw_desc batch_desc = {
 249                                 .op_flags = (idxd_op_batch << IDXD_CMD_OP_SHIFT) |
 250                                         IDXD_FLAG_COMPLETION_ADDR_VALID |
 251                                         IDXD_FLAG_REQUEST_COMPLETION,
 252                                 .desc_addr = __desc_idx_to_iova(idxd, idxd->batch_start),
 253                                 .completion = __desc_idx_to_iova(idxd, comp_idx),
 254                                 .size = idxd->batch_size,
 255                 };
 256
 257                 __idxd_movdir64b(idxd->portal, &batch_desc);
 258         } else {
 259                 /* special case batch size of 1, as not allowed by HW */
 260                 /* comp_idx == batch_start */
 261                 struct rte_idxd_hw_desc *desc = &idxd->desc_ring[comp_idx];
 262                 desc->op_flags |= IDXD_FLAG_COMPLETION_ADDR_VALID |
 263                                 IDXD_FLAG_REQUEST_COMPLETION;
 264                 desc->completion = __desc_idx_to_iova(idxd, comp_idx);
 265
 266                 __idxd_movdir64b(idxd->portal, desc);
 267         }
 268
 269         idxd->xstats.started += idxd->batch_size;
 270
 271         idxd->batch_start += idxd->batch_size;
 272         idxd->batch_start &= idxd->desc_ring_mask;
 273         idxd->batch_size = 0;
 274
 275         idxd->batch_idx_ring[idxd->batch_idx_write++] = comp_idx;
 276         if (idxd->batch_idx_write > idxd->max_batches)
 277                 idxd->batch_idx_write = 0;
 278
 279         return 0;
 280 }
 281
 282 static __rte_always_inline int
 283 __idxd_completed_ops(int dev_id, uint8_t max_ops,
 284                 uintptr_t *src_hdls, uintptr_t *dst_hdls)
 285 {
 286         struct rte_idxd_rawdev *idxd =
 287                         (struct rte_idxd_rawdev *)rte_rawdevs[dev_id].dev_private;
 288         unsigned short n, h_idx;
 289
 290         while (idxd->batch_idx_read != idxd->batch_idx_write) {
 291                 uint16_t idx_to_chk = idxd->batch_idx_ring[idxd->batch_idx_read];
 292                 volatile struct rte_idxd_completion *comp_to_chk =
 293                                 (struct rte_idxd_completion *)&idxd->desc_ring[idx_to_chk];
 294                 if (comp_to_chk->status == 0)
 295                         break;
 296                 /* avail points to one after the last one written */
 297                 idxd->hdls_avail = (idx_to_chk + 1) & idxd->desc_ring_mask;
 298                 idxd->batch_idx_read++;
 299                 if (idxd->batch_idx_read > idxd->max_batches)
 300                         idxd->batch_idx_read = 0;
 301         }
 302
 303         if (idxd->cfg.hdls_disable) {
 304                 n = (idxd->hdls_avail < idxd->hdls_read) ?
 305                                 (idxd->hdls_avail + idxd->desc_ring_mask + 1 - idxd->hdls_read) :
 306                                 (idxd->hdls_avail - idxd->hdls_read);
 307                 idxd->hdls_read = idxd->hdls_avail;
 308                 goto out;
 309         }
 310
 311         for (n = 0, h_idx = idxd->hdls_read;
 312                         n < max_ops && h_idx != idxd->hdls_avail; n++) {
 313                 src_hdls[n] = idxd->hdl_ring[h_idx].src;
 314                 dst_hdls[n] = idxd->hdl_ring[h_idx].dst;
 315                 if (++h_idx > idxd->desc_ring_mask)
 316                         h_idx = 0;
 317         }
 318         idxd->hdls_read = h_idx;
 319
 320 out:
 321         idxd->xstats.completed += n;
 322         return n;
 323 }
 324
 325 #endif