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1// SPDX-License-Identifier: GPL-2.0-or-later2/*3 * Copyright 2014 IBM Corp.4 */5 6#include <linux/spinlock.h>7#include <linux/kernel.h>8#include <linux/module.h>9#include <linux/device.h>10#include <linux/mutex.h>11#include <linux/init.h>12#include <linux/list.h>13#include <linux/mm.h>14#include <linux/of.h>15#include <linux/slab.h>16#include <linux/idr.h>17#include <linux/pci.h>18#include <linux/platform_device.h>19#include <linux/sched/task.h>20 21#include <asm/cputable.h>22#include <asm/mmu.h>23#include <misc/cxl-base.h>24 25#include "cxl.h"26#include "trace.h"27 28static DEFINE_SPINLOCK(adapter_idr_lock);29static DEFINE_IDR(cxl_adapter_idr);30 31uint cxl_verbose;32module_param_named(verbose, cxl_verbose, uint, 0600);33MODULE_PARM_DESC(verbose, "Enable verbose dmesg output");34 35const struct cxl_backend_ops *cxl_ops;36 37int cxl_afu_slbia(struct cxl_afu *afu)38{39 unsigned long timeout = jiffies + (HZ * CXL_TIMEOUT);40 41 pr_devel("cxl_afu_slbia issuing SLBIA command\n");42 cxl_p2n_write(afu, CXL_SLBIA_An, CXL_TLB_SLB_IQ_ALL);43 while (cxl_p2n_read(afu, CXL_SLBIA_An) & CXL_TLB_SLB_P) {44 if (time_after_eq(jiffies, timeout)) {45 dev_warn(&afu->dev, "WARNING: CXL AFU SLBIA timed out!\n");46 return -EBUSY;47 }48 /* If the adapter has gone down, we can assume that we49 * will PERST it and that will invalidate everything.50 */51 if (!cxl_ops->link_ok(afu->adapter, afu))52 return -EIO;53 cpu_relax();54 }55 return 0;56}57 58static inline void _cxl_slbia(struct cxl_context *ctx, struct mm_struct *mm)59{60 unsigned long flags;61 62 if (ctx->mm != mm)63 return;64 65 pr_devel("%s matched mm - card: %i afu: %i pe: %i\n", __func__,66 ctx->afu->adapter->adapter_num, ctx->afu->slice, ctx->pe);67 68 spin_lock_irqsave(&ctx->sste_lock, flags);69 trace_cxl_slbia(ctx);70 memset(ctx->sstp, 0, ctx->sst_size);71 spin_unlock_irqrestore(&ctx->sste_lock, flags);72 mb();73 cxl_afu_slbia(ctx->afu);74}75 76static inline void cxl_slbia_core(struct mm_struct *mm)77{78 struct cxl *adapter;79 struct cxl_afu *afu;80 struct cxl_context *ctx;81 int card, slice, id;82 83 pr_devel("%s called\n", __func__);84 85 spin_lock(&adapter_idr_lock);86 idr_for_each_entry(&cxl_adapter_idr, adapter, card) {87 /* XXX: Make this lookup faster with link from mm to ctx */88 spin_lock(&adapter->afu_list_lock);89 for (slice = 0; slice < adapter->slices; slice++) {90 afu = adapter->afu[slice];91 if (!afu || !afu->enabled)92 continue;93 rcu_read_lock();94 idr_for_each_entry(&afu->contexts_idr, ctx, id)95 _cxl_slbia(ctx, mm);96 rcu_read_unlock();97 }98 spin_unlock(&adapter->afu_list_lock);99 }100 spin_unlock(&adapter_idr_lock);101}102 103static struct cxl_calls cxl_calls = {104 .cxl_slbia = cxl_slbia_core,105 .owner = THIS_MODULE,106};107 108int cxl_alloc_sst(struct cxl_context *ctx)109{110 unsigned long vsid;111 u64 ea_mask, size, sstp0, sstp1;112 113 sstp0 = 0;114 sstp1 = 0;115 116 ctx->sst_size = PAGE_SIZE;117 ctx->sst_lru = 0;118 ctx->sstp = (struct cxl_sste *)get_zeroed_page(GFP_KERNEL);119 if (!ctx->sstp) {120 pr_err("cxl_alloc_sst: Unable to allocate segment table\n");121 return -ENOMEM;122 }123 pr_devel("SSTP allocated at 0x%p\n", ctx->sstp);124 125 vsid = get_kernel_vsid((u64)ctx->sstp, mmu_kernel_ssize) << 12;126 127 sstp0 |= (u64)mmu_kernel_ssize << CXL_SSTP0_An_B_SHIFT;128 sstp0 |= (SLB_VSID_KERNEL | mmu_psize_defs[mmu_linear_psize].sllp) << 50;129 130 size = (((u64)ctx->sst_size >> 8) - 1) << CXL_SSTP0_An_SegTableSize_SHIFT;131 if (unlikely(size & ~CXL_SSTP0_An_SegTableSize_MASK)) {132 WARN(1, "Impossible segment table size\n");133 return -EINVAL;134 }135 sstp0 |= size;136 137 if (mmu_kernel_ssize == MMU_SEGSIZE_256M)138 ea_mask = 0xfffff00ULL;139 else140 ea_mask = 0xffffffff00ULL;141 142 sstp0 |= vsid >> (50-14); /* Top 14 bits of VSID */143 sstp1 |= (vsid << (64-(50-14))) & ~ea_mask;144 sstp1 |= (u64)ctx->sstp & ea_mask;145 sstp1 |= CXL_SSTP1_An_V;146 147 pr_devel("Looked up %#llx: slbfee. %#llx (ssize: %x, vsid: %#lx), copied to SSTP0: %#llx, SSTP1: %#llx\n",148 (u64)ctx->sstp, (u64)ctx->sstp & ESID_MASK, mmu_kernel_ssize, vsid, sstp0, sstp1);149 150 /* Store calculated sstp hardware points for use later */151 ctx->sstp0 = sstp0;152 ctx->sstp1 = sstp1;153 154 return 0;155}156 157/* print buffer content as integers when debugging */158void cxl_dump_debug_buffer(void *buf, size_t buf_len)159{160#ifdef DEBUG161 int i, *ptr;162 163 /*164 * We want to regroup up to 4 integers per line, which means they165 * need to be in the same pr_devel() statement166 */167 ptr = (int *) buf;168 for (i = 0; i * 4 < buf_len; i += 4) {169 if ((i + 3) * 4 < buf_len)170 pr_devel("%.8x %.8x %.8x %.8x\n", ptr[i], ptr[i + 1],171 ptr[i + 2], ptr[i + 3]);172 else if ((i + 2) * 4 < buf_len)173 pr_devel("%.8x %.8x %.8x\n", ptr[i], ptr[i + 1],174 ptr[i + 2]);175 else if ((i + 1) * 4 < buf_len)176 pr_devel("%.8x %.8x\n", ptr[i], ptr[i + 1]);177 else178 pr_devel("%.8x\n", ptr[i]);179 }180#endif /* DEBUG */181}182 183/* Find a CXL adapter by it's number and increase it's refcount */184struct cxl *get_cxl_adapter(int num)185{186 struct cxl *adapter;187 188 spin_lock(&adapter_idr_lock);189 if ((adapter = idr_find(&cxl_adapter_idr, num)))190 get_device(&adapter->dev);191 spin_unlock(&adapter_idr_lock);192 193 return adapter;194}195 196static int cxl_alloc_adapter_nr(struct cxl *adapter)197{198 int i;199 200 idr_preload(GFP_KERNEL);201 spin_lock(&adapter_idr_lock);202 i = idr_alloc(&cxl_adapter_idr, adapter, 0, 0, GFP_NOWAIT);203 spin_unlock(&adapter_idr_lock);204 idr_preload_end();205 if (i < 0)206 return i;207 208 adapter->adapter_num = i;209 210 return 0;211}212 213void cxl_remove_adapter_nr(struct cxl *adapter)214{215 idr_remove(&cxl_adapter_idr, adapter->adapter_num);216}217 218struct cxl *cxl_alloc_adapter(void)219{220 struct cxl *adapter;221 222 if (!(adapter = kzalloc(sizeof(struct cxl), GFP_KERNEL)))223 return NULL;224 225 spin_lock_init(&adapter->afu_list_lock);226 227 if (cxl_alloc_adapter_nr(adapter))228 goto err1;229 230 if (dev_set_name(&adapter->dev, "card%i", adapter->adapter_num))231 goto err2;232 233 /* start with context lock taken */234 atomic_set(&adapter->contexts_num, -1);235 236 return adapter;237err2:238 cxl_remove_adapter_nr(adapter);239err1:240 kfree(adapter);241 return NULL;242}243 244struct cxl_afu *cxl_alloc_afu(struct cxl *adapter, int slice)245{246 struct cxl_afu *afu;247 248 if (!(afu = kzalloc(sizeof(struct cxl_afu), GFP_KERNEL)))249 return NULL;250 251 afu->adapter = adapter;252 afu->dev.parent = &adapter->dev;253 afu->dev.release = cxl_ops->release_afu;254 afu->slice = slice;255 idr_init(&afu->contexts_idr);256 mutex_init(&afu->contexts_lock);257 spin_lock_init(&afu->afu_cntl_lock);258 atomic_set(&afu->configured_state, -1);259 afu->prefault_mode = CXL_PREFAULT_NONE;260 afu->irqs_max = afu->adapter->user_irqs;261 262 return afu;263}264 265int cxl_afu_select_best_mode(struct cxl_afu *afu)266{267 if (afu->modes_supported & CXL_MODE_DIRECTED)268 return cxl_ops->afu_activate_mode(afu, CXL_MODE_DIRECTED);269 270 if (afu->modes_supported & CXL_MODE_DEDICATED)271 return cxl_ops->afu_activate_mode(afu, CXL_MODE_DEDICATED);272 273 dev_warn(&afu->dev, "No supported programming modes available\n");274 /* We don't fail this so the user can inspect sysfs */275 return 0;276}277 278int cxl_adapter_context_get(struct cxl *adapter)279{280 int rc;281 282 rc = atomic_inc_unless_negative(&adapter->contexts_num);283 return rc ? 0 : -EBUSY;284}285 286void cxl_adapter_context_put(struct cxl *adapter)287{288 atomic_dec_if_positive(&adapter->contexts_num);289}290 291int cxl_adapter_context_lock(struct cxl *adapter)292{293 int rc;294 /* no active contexts -> contexts_num == 0 */295 rc = atomic_cmpxchg(&adapter->contexts_num, 0, -1);296 return rc ? -EBUSY : 0;297}298 299void cxl_adapter_context_unlock(struct cxl *adapter)300{301 int val = atomic_cmpxchg(&adapter->contexts_num, -1, 0);302 303 /*304 * contexts lock taken -> contexts_num == -1305 * If not true then show a warning and force reset the lock.306 * This will happen when context_unlock was requested without307 * doing a context_lock.308 */309 if (val != -1) {310 atomic_set(&adapter->contexts_num, 0);311 WARN(1, "Adapter context unlocked with %d active contexts",312 val);313 }314}315 316static int __init init_cxl(void)317{318 int rc = 0;319 320 if (!tlbie_capable)321 return -EINVAL;322 323 if ((rc = cxl_file_init()))324 return rc;325 326 cxl_debugfs_init();327 328 /*329 * we don't register the callback on P9. slb callack is only330 * used for the PSL8 MMU and CX4.331 */332 if (cxl_is_power8()) {333 rc = register_cxl_calls(&cxl_calls);334 if (rc)335 goto err;336 }337 338 if (cpu_has_feature(CPU_FTR_HVMODE)) {339 cxl_ops = &cxl_native_ops;340 rc = pci_register_driver(&cxl_pci_driver);341 }342#ifdef CONFIG_PPC_PSERIES343 else {344 cxl_ops = &cxl_guest_ops;345 rc = platform_driver_register(&cxl_of_driver);346 }347#endif348 if (rc)349 goto err1;350 351 return 0;352err1:353 if (cxl_is_power8())354 unregister_cxl_calls(&cxl_calls);355err:356 cxl_debugfs_exit();357 cxl_file_exit();358 359 return rc;360}361 362static void exit_cxl(void)363{364 if (cpu_has_feature(CPU_FTR_HVMODE))365 pci_unregister_driver(&cxl_pci_driver);366#ifdef CONFIG_PPC_PSERIES367 else368 platform_driver_unregister(&cxl_of_driver);369#endif370 371 cxl_debugfs_exit();372 cxl_file_exit();373 if (cxl_is_power8())374 unregister_cxl_calls(&cxl_calls);375 idr_destroy(&cxl_adapter_idr);376}377 378module_init(init_cxl);379module_exit(exit_cxl);380 381MODULE_DESCRIPTION("IBM Coherent Accelerator");382MODULE_AUTHOR("Ian Munsie <imunsie@au1.ibm.com>");383MODULE_LICENSE("GPL");384