1/*- 2 * SPDX-License-Identifier: BSD-2-Clause 3 * 4 * Copyright (c) 2021 Microsoft Corp. 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 19 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 20 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 21 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 22 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 23 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 24 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 28 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 29 */ 30 31#include <sys/param.h> 32#include <sys/types.h> 33#include <sys/systm.h> 34#include <sys/bus.h> 35 36#include "mana.h" 37#include "shm_channel.h" 38#include "gdma_util.h" 39 40#define PAGE_FRAME_L48_WIDTH_BYTES 6 41#define PAGE_FRAME_L48_WIDTH_BITS (PAGE_FRAME_L48_WIDTH_BYTES * 8) 42#define PAGE_FRAME_L48_MASK 0x0000FFFFFFFFFFFF 43#define PAGE_FRAME_H4_WIDTH_BITS 4 44#define VECTOR_MASK 0xFFFF 45#define SHMEM_VF_RESET_STATE ((uint32_t)-1) 46 47#define SMC_MSG_TYPE_ESTABLISH_HWC 1 48#define SMC_MSG_TYPE_ESTABLISH_HWC_VERSION 0 49 50#define SMC_MSG_TYPE_DESTROY_HWC 2 51#define SMC_MSG_TYPE_DESTROY_HWC_VERSION 0 52 53#define SMC_MSG_DIRECTION_REQUEST 0 54#define SMC_MSG_DIRECTION_RESPONSE 1 55 56/* Structures labeled with "HW DATA" are exchanged with the hardware. All of 57 * them are naturally aligned and hence don't need __packed. 58 */ 59 60/* Shared memory channel protocol header 61 * 62 * msg_type: set on request and response; response matches request. 63 * msg_version: newer PF writes back older response (matching request) 64 * older PF acts on latest version known and sets that version in result 65 * (less than request). 66 * direction: 0 for request, VF->PF; 1 for response, PF->VF. 67 * status: 0 on request, 68 * operation result on response (success = 0, failure = 1 or greater). 69 * reset_vf: If set on either establish or destroy request, indicates perform 70 * FLR before/after the operation. 71 * owner_is_pf: 1 indicates PF owned, 0 indicates VF owned. 72 */ 73union smc_proto_hdr { 74 uint32_t as_uint32; 75 76 struct { 77 uint8_t msg_type : 3; 78 uint8_t msg_version : 3; 79 uint8_t reserved_1 : 1; 80 uint8_t direction : 1; 81 82 uint8_t status; 83 84 uint8_t reserved_2; 85 86 uint8_t reset_vf : 1; 87 uint8_t reserved_3 : 6; 88 uint8_t owner_is_pf : 1; 89 }; 90}; /* HW DATA */ 91 92#define SMC_APERTURE_BITS 256 93#define SMC_BASIC_UNIT (sizeof(uint32_t)) 94#define SMC_APERTURE_DWORDS (SMC_APERTURE_BITS / (SMC_BASIC_UNIT * 8)) 95#define SMC_LAST_DWORD (SMC_APERTURE_DWORDS - 1) 96 97static int 98mana_smc_poll_register(void __iomem *base, bool reset) 99{ 100 void __iomem *ptr = (uint8_t *)base + SMC_LAST_DWORD * SMC_BASIC_UNIT; 101 volatile uint32_t last_dword; 102 int i; 103 104 /* Poll the hardware for the ownership bit. This should be pretty fast, 105 * but let's do it in a loop just in case the hardware or the PF 106 * driver are temporarily busy. 107 */ 108 for (i = 0; i < 20 * 1000; i++) { 109 last_dword = readl(ptr); 110 111 /* shmem reads as 0xFFFFFFFF in the reset case */ 112 if (reset && last_dword == SHMEM_VF_RESET_STATE) 113 return 0; 114 115 /* If bit_31 is set, the PF currently owns the SMC. */ 116 if (!(last_dword & BIT(31))) 117 return 0; 118 119 DELAY(1000); 120 } 121 122 return ETIMEDOUT; 123} 124 125static int 126mana_smc_read_response(struct shm_channel *sc, uint32_t msg_type, 127 uint32_t msg_version, bool reset_vf) 128{ 129 void __iomem *base = sc->base; 130 union smc_proto_hdr hdr; 131 int err; 132 133 /* Wait for PF to respond. */ 134 err = mana_smc_poll_register(base, reset_vf); 135 if (err) 136 return err; 137 138 hdr.as_uint32 = 139 readl((uint8_t *)base + SMC_LAST_DWORD * SMC_BASIC_UNIT); 140 mana_dbg(NULL, "shm response 0x%x\n", hdr.as_uint32); 141 142 if (reset_vf && hdr.as_uint32 == SHMEM_VF_RESET_STATE) 143 return 0; 144 145 /* Validate protocol fields from the PF driver */ 146 if (hdr.msg_type != msg_type || hdr.msg_version > msg_version || 147 hdr.direction != SMC_MSG_DIRECTION_RESPONSE) { 148 device_printf(sc->dev, 149 "Wrong SMC response 0x%x, type=%d, ver=%d\n", 150 hdr.as_uint32, msg_type, msg_version); 151 return EPROTO; 152 } 153 154 /* Validate the operation result */ 155 if (hdr.status != 0) { 156 device_printf(sc->dev, 157 "SMC operation failed: 0x%x\n", hdr.status); 158 return EPROTO; 159 } 160 161 return 0; 162} 163 164void 165mana_smc_init(struct shm_channel *sc, device_t dev, void __iomem *base) 166{ 167 sc->dev = dev; 168 sc->base = base; 169} 170 171int 172mana_smc_setup_hwc(struct shm_channel *sc, bool reset_vf, uint64_t eq_addr, 173 uint64_t cq_addr, uint64_t rq_addr, uint64_t sq_addr, 174 uint32_t eq_msix_index) 175{ 176 union smc_proto_hdr *hdr; 177 uint16_t all_addr_h4bits = 0; 178 uint16_t frame_addr_seq = 0; 179 uint64_t frame_addr = 0; 180 uint8_t shm_buf[32]; 181 uint64_t *shmem; 182 uint32_t *dword; 183 uint8_t *ptr; 184 int err; 185 int i; 186 187 /* Ensure VF already has possession of shared memory */ 188 err = mana_smc_poll_register(sc->base, false); 189 if (err) { 190 device_printf(sc->dev, 191 "Timeout when setting up HWC: %d\n", err); 192 return err; 193 } 194 195 if (!IS_ALIGNED(eq_addr, PAGE_SIZE) || 196 !IS_ALIGNED(cq_addr, PAGE_SIZE) || 197 !IS_ALIGNED(rq_addr, PAGE_SIZE) || 198 !IS_ALIGNED(sq_addr, PAGE_SIZE)) 199 return EINVAL; 200 201 if ((eq_msix_index & VECTOR_MASK) != eq_msix_index) 202 return EINVAL; 203 204 /* Scheme for packing four addresses and extra info into 256 bits. 205 * 206 * Addresses must be page frame aligned, so only frame address bits 207 * are transferred. 208 * 209 * 52-bit frame addresses are split into the lower 48 bits and upper 210 * 4 bits. Lower 48 bits of 4 address are written sequentially from 211 * the start of the 256-bit shared memory region followed by 16 bits 212 * containing the upper 4 bits of the 4 addresses in sequence. 213 * 214 * A 16 bit EQ vector number fills out the next-to-last 32-bit dword. 215 * 216 * The final 32-bit dword is used for protocol control information as 217 * defined in smc_proto_hdr. 218 */ 219 220 memset(shm_buf, 0, sizeof(shm_buf)); 221 ptr = shm_buf; 222 223 /* EQ addr: low 48 bits of frame address */ 224 shmem = (uint64_t *)ptr; 225 frame_addr = PHYS_PFN(eq_addr); 226 *shmem = frame_addr & PAGE_FRAME_L48_MASK; 227 all_addr_h4bits |= (frame_addr >> PAGE_FRAME_L48_WIDTH_BITS) << 228 (frame_addr_seq++ * PAGE_FRAME_H4_WIDTH_BITS); 229 ptr += PAGE_FRAME_L48_WIDTH_BYTES; 230 231 /* CQ addr: low 48 bits of frame address */ 232 shmem = (uint64_t *)ptr; 233 frame_addr = PHYS_PFN(cq_addr); 234 *shmem = frame_addr & PAGE_FRAME_L48_MASK; 235 all_addr_h4bits |= (frame_addr >> PAGE_FRAME_L48_WIDTH_BITS) << 236 (frame_addr_seq++ * PAGE_FRAME_H4_WIDTH_BITS); 237 ptr += PAGE_FRAME_L48_WIDTH_BYTES; 238 239 /* RQ addr: low 48 bits of frame address */ 240 shmem = (uint64_t *)ptr; 241 frame_addr = PHYS_PFN(rq_addr); 242 *shmem = frame_addr & PAGE_FRAME_L48_MASK; 243 all_addr_h4bits |= (frame_addr >> PAGE_FRAME_L48_WIDTH_BITS) << 244 (frame_addr_seq++ * PAGE_FRAME_H4_WIDTH_BITS); 245 ptr += PAGE_FRAME_L48_WIDTH_BYTES; 246 247 /* SQ addr: low 48 bits of frame address */ 248 shmem = (uint64_t *)ptr; 249 frame_addr = PHYS_PFN(sq_addr); 250 *shmem = frame_addr & PAGE_FRAME_L48_MASK; 251 all_addr_h4bits |= (frame_addr >> PAGE_FRAME_L48_WIDTH_BITS) << 252 (frame_addr_seq++ * PAGE_FRAME_H4_WIDTH_BITS); 253 ptr += PAGE_FRAME_L48_WIDTH_BYTES; 254 255 /* High 4 bits of the four frame addresses */ 256 *((uint16_t *)ptr) = all_addr_h4bits; 257 ptr += sizeof(uint16_t); 258 259 /* EQ MSIX vector number */ 260 *((uint16_t *)ptr) = (uint16_t)eq_msix_index; 261 ptr += sizeof(uint16_t); 262 263 /* 32-bit protocol header in final dword */ 264 *((uint32_t *)ptr) = 0; 265 266 hdr = (union smc_proto_hdr *)ptr; 267 hdr->msg_type = SMC_MSG_TYPE_ESTABLISH_HWC; 268 hdr->msg_version = SMC_MSG_TYPE_ESTABLISH_HWC_VERSION; 269 hdr->direction = SMC_MSG_DIRECTION_REQUEST; 270 hdr->reset_vf = reset_vf; 271 272 /* Write 256-message buffer to shared memory (final 32-bit write 273 * triggers HW to set possession bit to PF). 274 */ 275 dword = (uint32_t *)shm_buf; 276 for (i = 0; i < SMC_APERTURE_DWORDS; i++) { 277 mana_dbg(NULL, "write shm_buf %d, val: 0x%x\n", 278 i, *dword); 279 writel((char *)sc->base + i * SMC_BASIC_UNIT, *dword++); 280 } 281 282 /* Read shmem response (polling for VF possession) and validate. 283 * For setup, waiting for response on shared memory is not strictly 284 * necessary, since wait occurs later for results to appear in EQE's. 285 */ 286 err = mana_smc_read_response(sc, SMC_MSG_TYPE_ESTABLISH_HWC, 287 SMC_MSG_TYPE_ESTABLISH_HWC_VERSION, reset_vf); 288 if (err) { 289 device_printf(sc->dev, 290 "Error when setting up HWC: %d\n", err); 291 return err; 292 } 293 294 return 0; 295} 296 297int 298mana_smc_teardown_hwc(struct shm_channel *sc, bool reset_vf) 299{ 300 union smc_proto_hdr hdr = {}; 301 int err; 302 303 /* Ensure already has possession of shared memory */ 304 err = mana_smc_poll_register(sc->base, false); 305 if (err) { 306 device_printf(sc->dev, "Timeout when tearing down HWC\n"); 307 return err; 308 } 309 310 /* Set up protocol header for HWC destroy message */ 311 hdr.msg_type = SMC_MSG_TYPE_DESTROY_HWC; 312 hdr.msg_version = SMC_MSG_TYPE_DESTROY_HWC_VERSION; 313 hdr.direction = SMC_MSG_DIRECTION_REQUEST; 314 hdr.reset_vf = reset_vf; 315 316 /* Write message in high 32 bits of 256-bit shared memory, causing HW 317 * to set possession bit to PF. 318 */ 319 writel((char *)sc->base + SMC_LAST_DWORD * SMC_BASIC_UNIT, 320 hdr.as_uint32); 321 322 /* Read shmem response (polling for VF possession) and validate. 323 * For teardown, waiting for response is required to ensure hardware 324 * invalidates MST entries before software frees memory. 325 */ 326 err = mana_smc_read_response(sc, SMC_MSG_TYPE_DESTROY_HWC, 327 SMC_MSG_TYPE_DESTROY_HWC_VERSION, reset_vf); 328 if (err) { 329 device_printf(sc->dev, 330 "Error when tearing down HWC: %d\n", err); 331 return err; 332 } 333 334 return 0; 335} 336