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 unsigned long flags; 63 64 if (ctx->mm != mm) 65 return; 66 67 pr_devel("%s matched mm - card: %i afu: %i pe: %i\n", __func__, 68 ctx->afu->adapter->adapter_num, ctx->afu->slice, ctx->pe); 69 70 spin_lock_irqsave(&ctx->sste_lock, flags); 71 trace_cxl_slbia(ctx); 72 memset(ctx->sstp, 0, ctx->sst_size); 73 spin_unlock_irqrestore(&ctx->sste_lock, flags); 74 mb(); 75 cxl_afu_slbia(ctx->afu); 76 } 77 78 static inline void cxl_slbia_core(struct mm_struct *mm) 79 { 80 struct cxl *adapter; 81 struct cxl_afu *afu; 82 struct cxl_context *ctx; 83 int card, slice, id; 84 85 pr_devel("%s called\n", __func__); 86 87 spin_lock(&adapter_idr_lock); 88 idr_for_each_entry(&cxl_adapter_idr, adapter, card) { 89 /* XXX: Make this lookup faster with link from mm to ctx */ 90 spin_lock(&adapter->afu_list_lock); 91 for (slice = 0; slice < adapter->slices; slice++) { 92 afu = adapter->afu[slice]; 93 if (!afu || !afu->enabled) 94 continue; 95 rcu_read_lock(); 96 idr_for_each_entry(&afu->contexts_idr, ctx, id) 97 _cxl_slbia(ctx, mm); 98 rcu_read_unlock(); 99 } 100 spin_unlock(&adapter->afu_list_lock); 101 } 102 spin_unlock(&adapter_idr_lock); 103 } 104 105 static struct cxl_calls cxl_calls = { 106 .cxl_slbia = cxl_slbia_core, 107 .cxl_pci_associate_default_context = _cxl_pci_associate_default_context, 108 .cxl_pci_disable_device = _cxl_pci_disable_device, 109 .cxl_next_msi_hwirq = _cxl_next_msi_hwirq, 110 .cxl_cx4_setup_msi_irqs = _cxl_cx4_setup_msi_irqs, 111 .cxl_cx4_teardown_msi_irqs = _cxl_cx4_teardown_msi_irqs, 112 .owner = THIS_MODULE, 113 }; 114 115 int cxl_alloc_sst(struct cxl_context *ctx) 116 { 117 unsigned long vsid; 118 u64 ea_mask, size, sstp0, sstp1; 119 120 sstp0 = 0; 121 sstp1 = 0; 122 123 ctx->sst_size = PAGE_SIZE; 124 ctx->sst_lru = 0; 125 ctx->sstp = (struct cxl_sste *)get_zeroed_page(GFP_KERNEL); 126 if (!ctx->sstp) { 127 pr_err("cxl_alloc_sst: Unable to allocate segment table\n"); 128 return -ENOMEM; 129 } 130 pr_devel("SSTP allocated at 0x%p\n", ctx->sstp); 131 132 vsid = get_kernel_vsid((u64)ctx->sstp, mmu_kernel_ssize) << 12; 133 134 sstp0 |= (u64)mmu_kernel_ssize << CXL_SSTP0_An_B_SHIFT; 135 sstp0 |= (SLB_VSID_KERNEL | mmu_psize_defs[mmu_linear_psize].sllp) << 50; 136 137 size = (((u64)ctx->sst_size >> 8) - 1) << CXL_SSTP0_An_SegTableSize_SHIFT; 138 if (unlikely(size & ~CXL_SSTP0_An_SegTableSize_MASK)) { 139 WARN(1, "Impossible segment table size\n"); 140 return -EINVAL; 141 } 142 sstp0 |= size; 143 144 if (mmu_kernel_ssize == MMU_SEGSIZE_256M) 145 ea_mask = 0xfffff00ULL; 146 else 147 ea_mask = 0xffffffff00ULL; 148 149 sstp0 |= vsid >> (50-14); /* Top 14 bits of VSID */ 150 sstp1 |= (vsid << (64-(50-14))) & ~ea_mask; 151 sstp1 |= (u64)ctx->sstp & ea_mask; 152 sstp1 |= CXL_SSTP1_An_V; 153 154 pr_devel("Looked up %#llx: slbfee. %#llx (ssize: %x, vsid: %#lx), copied to SSTP0: %#llx, SSTP1: %#llx\n", 155 (u64)ctx->sstp, (u64)ctx->sstp & ESID_MASK, mmu_kernel_ssize, vsid, sstp0, sstp1); 156 157 /* Store calculated sstp hardware points for use later */ 158 ctx->sstp0 = sstp0; 159 ctx->sstp1 = sstp1; 160 161 return 0; 162 } 163 164 /* print buffer content as integers when debugging */ 165 void cxl_dump_debug_buffer(void *buf, size_t buf_len) 166 { 167 #ifdef DEBUG 168 int i, *ptr; 169 170 /* 171 * We want to regroup up to 4 integers per line, which means they 172 * need to be in the same pr_devel() statement 173 */ 174 ptr = (int *) buf; 175 for (i = 0; i * 4 < buf_len; i += 4) { 176 if ((i + 3) * 4 < buf_len) 177 pr_devel("%.8x %.8x %.8x %.8x\n", ptr[i], ptr[i + 1], 178 ptr[i + 2], ptr[i + 3]); 179 else if ((i + 2) * 4 < buf_len) 180 pr_devel("%.8x %.8x %.8x\n", ptr[i], ptr[i + 1], 181 ptr[i + 2]); 182 else if ((i + 1) * 4 < buf_len) 183 pr_devel("%.8x %.8x\n", ptr[i], ptr[i + 1]); 184 else 185 pr_devel("%.8x\n", ptr[i]); 186 } 187 #endif /* DEBUG */ 188 } 189 190 /* Find a CXL adapter by it's number and increase it's refcount */ 191 struct cxl *get_cxl_adapter(int num) 192 { 193 struct cxl *adapter; 194 195 spin_lock(&adapter_idr_lock); 196 if ((adapter = idr_find(&cxl_adapter_idr, num))) 197 get_device(&adapter->dev); 198 spin_unlock(&adapter_idr_lock); 199 200 return adapter; 201 } 202 203 static int cxl_alloc_adapter_nr(struct cxl *adapter) 204 { 205 int i; 206 207 idr_preload(GFP_KERNEL); 208 spin_lock(&adapter_idr_lock); 209 i = idr_alloc(&cxl_adapter_idr, adapter, 0, 0, GFP_NOWAIT); 210 spin_unlock(&adapter_idr_lock); 211 idr_preload_end(); 212 if (i < 0) 213 return i; 214 215 adapter->adapter_num = i; 216 217 return 0; 218 } 219 220 void cxl_remove_adapter_nr(struct cxl *adapter) 221 { 222 idr_remove(&cxl_adapter_idr, adapter->adapter_num); 223 } 224 225 struct cxl *cxl_alloc_adapter(void) 226 { 227 struct cxl *adapter; 228 229 if (!(adapter = kzalloc(sizeof(struct cxl), GFP_KERNEL))) 230 return NULL; 231 232 spin_lock_init(&adapter->afu_list_lock); 233 234 if (cxl_alloc_adapter_nr(adapter)) 235 goto err1; 236 237 if (dev_set_name(&adapter->dev, "card%i", adapter->adapter_num)) 238 goto err2; 239 240 /* start with context lock taken */ 241 atomic_set(&adapter->contexts_num, -1); 242 243 return adapter; 244 err2: 245 cxl_remove_adapter_nr(adapter); 246 err1: 247 kfree(adapter); 248 return NULL; 249 } 250 251 struct cxl_afu *cxl_alloc_afu(struct cxl *adapter, int slice) 252 { 253 struct cxl_afu *afu; 254 255 if (!(afu = kzalloc(sizeof(struct cxl_afu), GFP_KERNEL))) 256 return NULL; 257 258 afu->adapter = adapter; 259 afu->dev.parent = &adapter->dev; 260 afu->dev.release = cxl_ops->release_afu; 261 afu->slice = slice; 262 idr_init(&afu->contexts_idr); 263 mutex_init(&afu->contexts_lock); 264 spin_lock_init(&afu->afu_cntl_lock); 265 atomic_set(&afu->configured_state, -1); 266 afu->prefault_mode = CXL_PREFAULT_NONE; 267 afu->irqs_max = afu->adapter->user_irqs; 268 269 return afu; 270 } 271 272 int cxl_afu_select_best_mode(struct cxl_afu *afu) 273 { 274 if (afu->modes_supported & CXL_MODE_DIRECTED) 275 return cxl_ops->afu_activate_mode(afu, CXL_MODE_DIRECTED); 276 277 if (afu->modes_supported & CXL_MODE_DEDICATED) 278 return cxl_ops->afu_activate_mode(afu, CXL_MODE_DEDICATED); 279 280 dev_warn(&afu->dev, "No supported programming modes available\n"); 281 /* We don't fail this so the user can inspect sysfs */ 282 return 0; 283 } 284 285 int cxl_adapter_context_get(struct cxl *adapter) 286 { 287 int rc; 288 289 rc = atomic_inc_unless_negative(&adapter->contexts_num); 290 return rc >= 0 ? 0 : -EBUSY; 291 } 292 293 void cxl_adapter_context_put(struct cxl *adapter) 294 { 295 atomic_dec_if_positive(&adapter->contexts_num); 296 } 297 298 int cxl_adapter_context_lock(struct cxl *adapter) 299 { 300 int rc; 301 /* no active contexts -> contexts_num == 0 */ 302 rc = atomic_cmpxchg(&adapter->contexts_num, 0, -1); 303 return rc ? -EBUSY : 0; 304 } 305 306 void cxl_adapter_context_unlock(struct cxl *adapter) 307 { 308 int val = atomic_cmpxchg(&adapter->contexts_num, -1, 0); 309 310 /* 311 * contexts lock taken -> contexts_num == -1 312 * If not true then show a warning and force reset the lock. 313 * This will happen when context_unlock was requested without 314 * doing a context_lock. 315 */ 316 if (val != -1) { 317 atomic_set(&adapter->contexts_num, 0); 318 WARN(1, "Adapter context unlocked with %d active contexts", 319 val); 320 } 321 } 322 323 static int __init init_cxl(void) 324 { 325 int rc = 0; 326 327 if ((rc = cxl_file_init())) 328 return rc; 329 330 cxl_debugfs_init(); 331 332 /* 333 * we don't register the callback on P9. slb callack is only 334 * used for the PSL8 MMU and CX4. 335 */ 336 if (cxl_is_power8()) { 337 rc = register_cxl_calls(&cxl_calls); 338 if (rc) 339 goto err; 340 } 341 342 if (cpu_has_feature(CPU_FTR_HVMODE)) { 343 cxl_ops = &cxl_native_ops; 344 rc = pci_register_driver(&cxl_pci_driver); 345 } 346 #ifdef CONFIG_PPC_PSERIES 347 else { 348 cxl_ops = &cxl_guest_ops; 349 rc = platform_driver_register(&cxl_of_driver); 350 } 351 #endif 352 if (rc) 353 goto err1; 354 355 return 0; 356 err1: 357 if (cxl_is_power8()) 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 if (cxl_is_power8()) 378 unregister_cxl_calls(&cxl_calls); 379 idr_destroy(&cxl_adapter_idr); 380 } 381 382 module_init(init_cxl); 383 module_exit(exit_cxl); 384 385 MODULE_DESCRIPTION("IBM Coherent Accelerator"); 386 MODULE_AUTHOR("Ian Munsie <imunsie@au1.ibm.com>"); 387 MODULE_LICENSE("GPL"); 388