1 | // SPDX-License-Identifier: GPL-2.0-or-later |
2 | /* |
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 | |
28 | static DEFINE_SPINLOCK(adapter_idr_lock); |
29 | static DEFINE_IDR(cxl_adapter_idr); |
30 | |
31 | uint cxl_verbose; |
32 | module_param_named(verbose, cxl_verbose, uint, 0600); |
33 | MODULE_PARM_DESC(verbose, "Enable verbose dmesg output" ); |
34 | |
35 | const struct cxl_backend_ops *cxl_ops; |
36 | |
37 | int 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, reg: CXL_SLBIA_An, CXL_TLB_SLB_IQ_ALL); |
43 | while (cxl_p2n_read(afu, reg: 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 we |
49 | * 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 | |
58 | static 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(lock: &ctx->sste_lock, flags); |
72 | mb(); |
73 | cxl_afu_slbia(afu: ctx->afu); |
74 | } |
75 | |
76 | static 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(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(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(lock: &adapter->afu_list_lock); |
99 | } |
100 | spin_unlock(lock: &adapter_idr_lock); |
101 | } |
102 | |
103 | static struct cxl_calls cxl_calls = { |
104 | .cxl_slbia = cxl_slbia_core, |
105 | .owner = THIS_MODULE, |
106 | }; |
107 | |
108 | int 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 | else |
140 | 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 */ |
158 | void cxl_dump_debug_buffer(void *buf, size_t buf_len) |
159 | { |
160 | #ifdef DEBUG |
161 | int i, *ptr; |
162 | |
163 | /* |
164 | * We want to regroup up to 4 integers per line, which means they |
165 | * need to be in the same pr_devel() statement |
166 | */ |
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 | else |
178 | 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 */ |
184 | struct cxl *get_cxl_adapter(int num) |
185 | { |
186 | struct cxl *adapter; |
187 | |
188 | spin_lock(lock: &adapter_idr_lock); |
189 | if ((adapter = idr_find(&cxl_adapter_idr, id: num))) |
190 | get_device(dev: &adapter->dev); |
191 | spin_unlock(lock: &adapter_idr_lock); |
192 | |
193 | return adapter; |
194 | } |
195 | |
196 | static int cxl_alloc_adapter_nr(struct cxl *adapter) |
197 | { |
198 | int i; |
199 | |
200 | idr_preload(GFP_KERNEL); |
201 | spin_lock(lock: &adapter_idr_lock); |
202 | i = idr_alloc(&cxl_adapter_idr, ptr: adapter, start: 0, end: 0, GFP_NOWAIT); |
203 | spin_unlock(lock: &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 | |
213 | void cxl_remove_adapter_nr(struct cxl *adapter) |
214 | { |
215 | idr_remove(&cxl_adapter_idr, id: adapter->adapter_num); |
216 | } |
217 | |
218 | struct cxl *cxl_alloc_adapter(void) |
219 | { |
220 | struct cxl *adapter; |
221 | |
222 | if (!(adapter = kzalloc(size: 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(dev: &adapter->dev, name: "card%i" , adapter->adapter_num)) |
231 | goto err2; |
232 | |
233 | /* start with context lock taken */ |
234 | atomic_set(v: &adapter->contexts_num, i: -1); |
235 | |
236 | return adapter; |
237 | err2: |
238 | cxl_remove_adapter_nr(adapter); |
239 | err1: |
240 | kfree(objp: adapter); |
241 | return NULL; |
242 | } |
243 | |
244 | struct cxl_afu *cxl_alloc_afu(struct cxl *adapter, int slice) |
245 | { |
246 | struct cxl_afu *afu; |
247 | |
248 | if (!(afu = kzalloc(size: 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(idr: &afu->contexts_idr); |
256 | mutex_init(&afu->contexts_lock); |
257 | spin_lock_init(&afu->afu_cntl_lock); |
258 | atomic_set(v: &afu->configured_state, i: -1); |
259 | afu->prefault_mode = CXL_PREFAULT_NONE; |
260 | afu->irqs_max = afu->adapter->user_irqs; |
261 | |
262 | return afu; |
263 | } |
264 | |
265 | int 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 | |
278 | int cxl_adapter_context_get(struct cxl *adapter) |
279 | { |
280 | int rc; |
281 | |
282 | rc = atomic_inc_unless_negative(v: &adapter->contexts_num); |
283 | return rc ? 0 : -EBUSY; |
284 | } |
285 | |
286 | void cxl_adapter_context_put(struct cxl *adapter) |
287 | { |
288 | atomic_dec_if_positive(v: &adapter->contexts_num); |
289 | } |
290 | |
291 | int cxl_adapter_context_lock(struct cxl *adapter) |
292 | { |
293 | int rc; |
294 | /* no active contexts -> contexts_num == 0 */ |
295 | rc = atomic_cmpxchg(v: &adapter->contexts_num, old: 0, new: -1); |
296 | return rc ? -EBUSY : 0; |
297 | } |
298 | |
299 | void cxl_adapter_context_unlock(struct cxl *adapter) |
300 | { |
301 | int val = atomic_cmpxchg(v: &adapter->contexts_num, old: -1, new: 0); |
302 | |
303 | /* |
304 | * contexts lock taken -> contexts_num == -1 |
305 | * If not true then show a warning and force reset the lock. |
306 | * This will happen when context_unlock was requested without |
307 | * doing a context_lock. |
308 | */ |
309 | if (val != -1) { |
310 | atomic_set(v: &adapter->contexts_num, i: 0); |
311 | WARN(1, "Adapter context unlocked with %d active contexts" , |
312 | val); |
313 | } |
314 | } |
315 | |
316 | static 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 only |
330 | * used for the PSL8 MMU and CX4. |
331 | */ |
332 | if (cxl_is_power8()) { |
333 | rc = register_cxl_calls(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_PSERIES |
343 | else { |
344 | cxl_ops = &cxl_guest_ops; |
345 | rc = platform_driver_register(&cxl_of_driver); |
346 | } |
347 | #endif |
348 | if (rc) |
349 | goto err1; |
350 | |
351 | return 0; |
352 | err1: |
353 | if (cxl_is_power8()) |
354 | unregister_cxl_calls(calls: &cxl_calls); |
355 | err: |
356 | cxl_debugfs_exit(); |
357 | cxl_file_exit(); |
358 | |
359 | return rc; |
360 | } |
361 | |
362 | static void exit_cxl(void) |
363 | { |
364 | if (cpu_has_feature(CPU_FTR_HVMODE)) |
365 | pci_unregister_driver(dev: &cxl_pci_driver); |
366 | #ifdef CONFIG_PPC_PSERIES |
367 | else |
368 | platform_driver_unregister(&cxl_of_driver); |
369 | #endif |
370 | |
371 | cxl_debugfs_exit(); |
372 | cxl_file_exit(); |
373 | if (cxl_is_power8()) |
374 | unregister_cxl_calls(calls: &cxl_calls); |
375 | idr_destroy(&cxl_adapter_idr); |
376 | } |
377 | |
378 | module_init(init_cxl); |
379 | module_exit(exit_cxl); |
380 | |
381 | MODULE_DESCRIPTION("IBM Coherent Accelerator" ); |
382 | MODULE_AUTHOR("Ian Munsie <imunsie@au1.ibm.com>" ); |
383 | MODULE_LICENSE("GPL" ); |
384 | |