1 /* 2 * Copyright 2014 IBM Corp. 3 * 4 * This program is free software; you can redistribute it and/or 5 * modify it under the terms of the GNU General Public License 6 * as published by the Free Software Foundation; either version 7 * 2 of the License, or (at your option) any later version. 8 */ 9 10 #include <linux/spinlock.h> 11 #include <linux/kernel.h> 12 #include <linux/module.h> 13 #include <linux/device.h> 14 #include <linux/mutex.h> 15 #include <linux/init.h> 16 #include <linux/list.h> 17 #include <linux/mm.h> 18 #include <linux/of.h> 19 #include <linux/slab.h> 20 #include <linux/idr.h> 21 #include <linux/pci.h> 22 #include <linux/sched/task.h> 23 24 #include <asm/cputable.h> 25 #include <misc/cxl-base.h> 26 27 #include "cxl.h" 28 #include "trace.h" 29 30 static DEFINE_SPINLOCK(adapter_idr_lock); 31 static DEFINE_IDR(cxl_adapter_idr); 32 33 uint cxl_verbose; 34 module_param_named(verbose, cxl_verbose, uint, 0600); 35 MODULE_PARM_DESC(verbose, "Enable verbose dmesg output"); 36 37 const struct cxl_backend_ops *cxl_ops; 38 39 int cxl_afu_slbia(struct cxl_afu *afu) 40 { 41 unsigned long timeout = jiffies + (HZ * CXL_TIMEOUT); 42 43 pr_devel("cxl_afu_slbia issuing SLBIA command\n"); 44 cxl_p2n_write(afu, CXL_SLBIA_An, CXL_TLB_SLB_IQ_ALL); 45 while (cxl_p2n_read(afu, CXL_SLBIA_An) & CXL_TLB_SLB_P) { 46 if (time_after_eq(jiffies, timeout)) { 47 dev_warn(&afu->dev, "WARNING: CXL AFU SLBIA timed out!\n"); 48 return -EBUSY; 49 } 50 /* If the adapter has gone down, we can assume that we 51 * will PERST it and that will invalidate everything. 52 */ 53 if (!cxl_ops->link_ok(afu->adapter, afu)) 54 return -EIO; 55 cpu_relax(); 56 } 57 return 0; 58 } 59 60 static inline void _cxl_slbia(struct cxl_context *ctx, struct mm_struct *mm) 61 { 62 struct task_struct *task; 63 unsigned long flags; 64 if (!(task = get_pid_task(ctx->pid, PIDTYPE_PID))) { 65 pr_devel("%s unable to get task %i\n", 66 __func__, pid_nr(ctx->pid)); 67 return; 68 } 69 70 if (task->mm != mm) 71 goto out_put; 72 73 pr_devel("%s matched mm - card: %i afu: %i pe: %i\n", __func__, 74 ctx->afu->adapter->adapter_num, ctx->afu->slice, ctx->pe); 75 76 spin_lock_irqsave(&ctx->sste_lock, flags); 77 trace_cxl_slbia(ctx); 78 memset(ctx->sstp, 0, ctx->sst_size); 79 spin_unlock_irqrestore(&ctx->sste_lock, flags); 80 mb(); 81 cxl_afu_slbia(ctx->afu); 82 out_put: 83 put_task_struct(task); 84 } 85 86 static inline void cxl_slbia_core(struct mm_struct *mm) 87 { 88 struct cxl *adapter; 89 struct cxl_afu *afu; 90 struct cxl_context *ctx; 91 int card, slice, id; 92 93 pr_devel("%s called\n", __func__); 94 95 spin_lock(&adapter_idr_lock); 96 idr_for_each_entry(&cxl_adapter_idr, adapter, card) { 97 /* XXX: Make this lookup faster with link from mm to ctx */ 98 spin_lock(&adapter->afu_list_lock); 99 for (slice = 0; slice < adapter->slices; slice++) { 100 afu = adapter->afu[slice]; 101 if (!afu || !afu->enabled) 102 continue; 103 rcu_read_lock(); 104 idr_for_each_entry(&afu->contexts_idr, ctx, id) 105 _cxl_slbia(ctx, mm); 106 rcu_read_unlock(); 107 } 108 spin_unlock(&adapter->afu_list_lock); 109 } 110 spin_unlock(&adapter_idr_lock); 111 } 112 113 static struct cxl_calls cxl_calls = { 114 .cxl_slbia = cxl_slbia_core, 115 .cxl_pci_associate_default_context = _cxl_pci_associate_default_context, 116 .cxl_pci_disable_device = _cxl_pci_disable_device, 117 .cxl_next_msi_hwirq = _cxl_next_msi_hwirq, 118 .cxl_cx4_setup_msi_irqs = _cxl_cx4_setup_msi_irqs, 119 .cxl_cx4_teardown_msi_irqs = _cxl_cx4_teardown_msi_irqs, 120 .owner = THIS_MODULE, 121 }; 122 123 int cxl_alloc_sst(struct cxl_context *ctx) 124 { 125 unsigned long vsid; 126 u64 ea_mask, size, sstp0, sstp1; 127 128 sstp0 = 0; 129 sstp1 = 0; 130 131 ctx->sst_size = PAGE_SIZE; 132 ctx->sst_lru = 0; 133 ctx->sstp = (struct cxl_sste *)get_zeroed_page(GFP_KERNEL); 134 if (!ctx->sstp) { 135 pr_err("cxl_alloc_sst: Unable to allocate segment table\n"); 136 return -ENOMEM; 137 } 138 pr_devel("SSTP allocated at 0x%p\n", ctx->sstp); 139 140 vsid = get_kernel_vsid((u64)ctx->sstp, mmu_kernel_ssize) << 12; 141 142 sstp0 |= (u64)mmu_kernel_ssize << CXL_SSTP0_An_B_SHIFT; 143 sstp0 |= (SLB_VSID_KERNEL | mmu_psize_defs[mmu_linear_psize].sllp) << 50; 144 145 size = (((u64)ctx->sst_size >> 8) - 1) << CXL_SSTP0_An_SegTableSize_SHIFT; 146 if (unlikely(size & ~CXL_SSTP0_An_SegTableSize_MASK)) { 147 WARN(1, "Impossible segment table size\n"); 148 return -EINVAL; 149 } 150 sstp0 |= size; 151 152 if (mmu_kernel_ssize == MMU_SEGSIZE_256M) 153 ea_mask = 0xfffff00ULL; 154 else 155 ea_mask = 0xffffffff00ULL; 156 157 sstp0 |= vsid >> (50-14); /* Top 14 bits of VSID */ 158 sstp1 |= (vsid << (64-(50-14))) & ~ea_mask; 159 sstp1 |= (u64)ctx->sstp & ea_mask; 160 sstp1 |= CXL_SSTP1_An_V; 161 162 pr_devel("Looked up %#llx: slbfee. %#llx (ssize: %x, vsid: %#lx), copied to SSTP0: %#llx, SSTP1: %#llx\n", 163 (u64)ctx->sstp, (u64)ctx->sstp & ESID_MASK, mmu_kernel_ssize, vsid, sstp0, sstp1); 164 165 /* Store calculated sstp hardware points for use later */ 166 ctx->sstp0 = sstp0; 167 ctx->sstp1 = sstp1; 168 169 return 0; 170 } 171 172 /* print buffer content as integers when debugging */ 173 void cxl_dump_debug_buffer(void *buf, size_t buf_len) 174 { 175 #ifdef DEBUG 176 int i, *ptr; 177 178 /* 179 * We want to regroup up to 4 integers per line, which means they 180 * need to be in the same pr_devel() statement 181 */ 182 ptr = (int *) buf; 183 for (i = 0; i * 4 < buf_len; i += 4) { 184 if ((i + 3) * 4 < buf_len) 185 pr_devel("%.8x %.8x %.8x %.8x\n", ptr[i], ptr[i + 1], 186 ptr[i + 2], ptr[i + 3]); 187 else if ((i + 2) * 4 < buf_len) 188 pr_devel("%.8x %.8x %.8x\n", ptr[i], ptr[i + 1], 189 ptr[i + 2]); 190 else if ((i + 1) * 4 < buf_len) 191 pr_devel("%.8x %.8x\n", ptr[i], ptr[i + 1]); 192 else 193 pr_devel("%.8x\n", ptr[i]); 194 } 195 #endif /* DEBUG */ 196 } 197 198 /* Find a CXL adapter by it's number and increase it's refcount */ 199 struct cxl *get_cxl_adapter(int num) 200 { 201 struct cxl *adapter; 202 203 spin_lock(&adapter_idr_lock); 204 if ((adapter = idr_find(&cxl_adapter_idr, num))) 205 get_device(&adapter->dev); 206 spin_unlock(&adapter_idr_lock); 207 208 return adapter; 209 } 210 211 static int cxl_alloc_adapter_nr(struct cxl *adapter) 212 { 213 int i; 214 215 idr_preload(GFP_KERNEL); 216 spin_lock(&adapter_idr_lock); 217 i = idr_alloc(&cxl_adapter_idr, adapter, 0, 0, GFP_NOWAIT); 218 spin_unlock(&adapter_idr_lock); 219 idr_preload_end(); 220 if (i < 0) 221 return i; 222 223 adapter->adapter_num = i; 224 225 return 0; 226 } 227 228 void cxl_remove_adapter_nr(struct cxl *adapter) 229 { 230 idr_remove(&cxl_adapter_idr, adapter->adapter_num); 231 } 232 233 struct cxl *cxl_alloc_adapter(void) 234 { 235 struct cxl *adapter; 236 237 if (!(adapter = kzalloc(sizeof(struct cxl), GFP_KERNEL))) 238 return NULL; 239 240 spin_lock_init(&adapter->afu_list_lock); 241 242 if (cxl_alloc_adapter_nr(adapter)) 243 goto err1; 244 245 if (dev_set_name(&adapter->dev, "card%i", adapter->adapter_num)) 246 goto err2; 247 248 /* start with context lock taken */ 249 atomic_set(&adapter->contexts_num, -1); 250 251 return adapter; 252 err2: 253 cxl_remove_adapter_nr(adapter); 254 err1: 255 kfree(adapter); 256 return NULL; 257 } 258 259 struct cxl_afu *cxl_alloc_afu(struct cxl *adapter, int slice) 260 { 261 struct cxl_afu *afu; 262 263 if (!(afu = kzalloc(sizeof(struct cxl_afu), GFP_KERNEL))) 264 return NULL; 265 266 afu->adapter = adapter; 267 afu->dev.parent = &adapter->dev; 268 afu->dev.release = cxl_ops->release_afu; 269 afu->slice = slice; 270 idr_init(&afu->contexts_idr); 271 mutex_init(&afu->contexts_lock); 272 spin_lock_init(&afu->afu_cntl_lock); 273 atomic_set(&afu->configured_state, -1); 274 afu->prefault_mode = CXL_PREFAULT_NONE; 275 afu->irqs_max = afu->adapter->user_irqs; 276 277 return afu; 278 } 279 280 int cxl_afu_select_best_mode(struct cxl_afu *afu) 281 { 282 if (afu->modes_supported & CXL_MODE_DIRECTED) 283 return cxl_ops->afu_activate_mode(afu, CXL_MODE_DIRECTED); 284 285 if (afu->modes_supported & CXL_MODE_DEDICATED) 286 return cxl_ops->afu_activate_mode(afu, CXL_MODE_DEDICATED); 287 288 dev_warn(&afu->dev, "No supported programming modes available\n"); 289 /* We don't fail this so the user can inspect sysfs */ 290 return 0; 291 } 292 293 int cxl_adapter_context_get(struct cxl *adapter) 294 { 295 int rc; 296 297 rc = atomic_inc_unless_negative(&adapter->contexts_num); 298 return rc >= 0 ? 0 : -EBUSY; 299 } 300 301 void cxl_adapter_context_put(struct cxl *adapter) 302 { 303 atomic_dec_if_positive(&adapter->contexts_num); 304 } 305 306 int cxl_adapter_context_lock(struct cxl *adapter) 307 { 308 int rc; 309 /* no active contexts -> contexts_num == 0 */ 310 rc = atomic_cmpxchg(&adapter->contexts_num, 0, -1); 311 return rc ? -EBUSY : 0; 312 } 313 314 void cxl_adapter_context_unlock(struct cxl *adapter) 315 { 316 int val = atomic_cmpxchg(&adapter->contexts_num, -1, 0); 317 318 /* 319 * contexts lock taken -> contexts_num == -1 320 * If not true then show a warning and force reset the lock. 321 * This will happen when context_unlock was requested without 322 * doing a context_lock. 323 */ 324 if (val != -1) { 325 atomic_set(&adapter->contexts_num, 0); 326 WARN(1, "Adapter context unlocked with %d active contexts", 327 val); 328 } 329 } 330 331 static int __init init_cxl(void) 332 { 333 int rc = 0; 334 335 if ((rc = cxl_file_init())) 336 return rc; 337 338 cxl_debugfs_init(); 339 340 if ((rc = register_cxl_calls(&cxl_calls))) 341 goto err; 342 343 if (cpu_has_feature(CPU_FTR_HVMODE)) { 344 cxl_ops = &cxl_native_ops; 345 rc = pci_register_driver(&cxl_pci_driver); 346 } 347 #ifdef CONFIG_PPC_PSERIES 348 else { 349 cxl_ops = &cxl_guest_ops; 350 rc = platform_driver_register(&cxl_of_driver); 351 } 352 #endif 353 if (rc) 354 goto err1; 355 356 return 0; 357 err1: 358 unregister_cxl_calls(&cxl_calls); 359 err: 360 cxl_debugfs_exit(); 361 cxl_file_exit(); 362 363 return rc; 364 } 365 366 static void exit_cxl(void) 367 { 368 if (cpu_has_feature(CPU_FTR_HVMODE)) 369 pci_unregister_driver(&cxl_pci_driver); 370 #ifdef CONFIG_PPC_PSERIES 371 else 372 platform_driver_unregister(&cxl_of_driver); 373 #endif 374 375 cxl_debugfs_exit(); 376 cxl_file_exit(); 377 unregister_cxl_calls(&cxl_calls); 378 idr_destroy(&cxl_adapter_idr); 379 } 380 381 module_init(init_cxl); 382 module_exit(exit_cxl); 383 384 MODULE_DESCRIPTION("IBM Coherent Accelerator"); 385 MODULE_AUTHOR("Ian Munsie <imunsie@au1.ibm.com>"); 386 MODULE_LICENSE("GPL"); 387