xref: /openbmc/linux/drivers/cxl/pmem.c (revision 25879d7b)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /* Copyright(c) 2021 Intel Corporation. All rights reserved. */
3 #include <linux/libnvdimm.h>
4 #include <asm/unaligned.h>
5 #include <linux/device.h>
6 #include <linux/module.h>
7 #include <linux/ndctl.h>
8 #include <linux/async.h>
9 #include <linux/slab.h>
10 #include <linux/nd.h>
11 #include "cxlmem.h"
12 #include "cxl.h"
13 
14 extern const struct nvdimm_security_ops *cxl_security_ops;
15 
16 static __read_mostly DECLARE_BITMAP(exclusive_cmds, CXL_MEM_COMMAND_ID_MAX);
17 
18 static void clear_exclusive(void *cxlds)
19 {
20 	clear_exclusive_cxl_commands(cxlds, exclusive_cmds);
21 }
22 
23 static void unregister_nvdimm(void *nvdimm)
24 {
25 	nvdimm_delete(nvdimm);
26 }
27 
28 static ssize_t provider_show(struct device *dev, struct device_attribute *attr, char *buf)
29 {
30 	struct nvdimm *nvdimm = to_nvdimm(dev);
31 	struct cxl_nvdimm *cxl_nvd = nvdimm_provider_data(nvdimm);
32 
33 	return sysfs_emit(buf, "%s\n", dev_name(&cxl_nvd->dev));
34 }
35 static DEVICE_ATTR_RO(provider);
36 
37 static ssize_t id_show(struct device *dev, struct device_attribute *attr, char *buf)
38 {
39 	struct nvdimm *nvdimm = to_nvdimm(dev);
40 	struct cxl_nvdimm *cxl_nvd = nvdimm_provider_data(nvdimm);
41 	struct cxl_dev_state *cxlds = cxl_nvd->cxlmd->cxlds;
42 
43 	return sysfs_emit(buf, "%lld\n", cxlds->serial);
44 }
45 static DEVICE_ATTR_RO(id);
46 
47 static struct attribute *cxl_dimm_attributes[] = {
48 	&dev_attr_id.attr,
49 	&dev_attr_provider.attr,
50 	NULL
51 };
52 
53 static const struct attribute_group cxl_dimm_attribute_group = {
54 	.name = "cxl",
55 	.attrs = cxl_dimm_attributes,
56 };
57 
58 static const struct attribute_group *cxl_dimm_attribute_groups[] = {
59 	&cxl_dimm_attribute_group,
60 	NULL
61 };
62 
63 static int cxl_nvdimm_probe(struct device *dev)
64 {
65 	struct cxl_nvdimm *cxl_nvd = to_cxl_nvdimm(dev);
66 	struct cxl_memdev *cxlmd = cxl_nvd->cxlmd;
67 	struct cxl_nvdimm_bridge *cxl_nvb = cxlmd->cxl_nvb;
68 	unsigned long flags = 0, cmd_mask = 0;
69 	struct cxl_dev_state *cxlds = cxlmd->cxlds;
70 	struct nvdimm *nvdimm;
71 	int rc;
72 
73 	set_exclusive_cxl_commands(cxlds, exclusive_cmds);
74 	rc = devm_add_action_or_reset(dev, clear_exclusive, cxlds);
75 	if (rc)
76 		return rc;
77 
78 	set_bit(NDD_LABELING, &flags);
79 	set_bit(NDD_REGISTER_SYNC, &flags);
80 	set_bit(ND_CMD_GET_CONFIG_SIZE, &cmd_mask);
81 	set_bit(ND_CMD_GET_CONFIG_DATA, &cmd_mask);
82 	set_bit(ND_CMD_SET_CONFIG_DATA, &cmd_mask);
83 	nvdimm = __nvdimm_create(cxl_nvb->nvdimm_bus, cxl_nvd,
84 				 cxl_dimm_attribute_groups, flags,
85 				 cmd_mask, 0, NULL, cxl_nvd->dev_id,
86 				 cxl_security_ops, NULL);
87 	if (!nvdimm)
88 		return -ENOMEM;
89 
90 	dev_set_drvdata(dev, nvdimm);
91 	return devm_add_action_or_reset(dev, unregister_nvdimm, nvdimm);
92 }
93 
94 static struct cxl_driver cxl_nvdimm_driver = {
95 	.name = "cxl_nvdimm",
96 	.probe = cxl_nvdimm_probe,
97 	.id = CXL_DEVICE_NVDIMM,
98 	.drv = {
99 		.suppress_bind_attrs = true,
100 	},
101 };
102 
103 static int cxl_pmem_get_config_size(struct cxl_dev_state *cxlds,
104 				    struct nd_cmd_get_config_size *cmd,
105 				    unsigned int buf_len)
106 {
107 	if (sizeof(*cmd) > buf_len)
108 		return -EINVAL;
109 
110 	*cmd = (struct nd_cmd_get_config_size) {
111 		 .config_size = cxlds->lsa_size,
112 		 .max_xfer = cxlds->payload_size - sizeof(struct cxl_mbox_set_lsa),
113 	};
114 
115 	return 0;
116 }
117 
118 static int cxl_pmem_get_config_data(struct cxl_dev_state *cxlds,
119 				    struct nd_cmd_get_config_data_hdr *cmd,
120 				    unsigned int buf_len)
121 {
122 	struct cxl_mbox_get_lsa get_lsa;
123 	struct cxl_mbox_cmd mbox_cmd;
124 	int rc;
125 
126 	if (sizeof(*cmd) > buf_len)
127 		return -EINVAL;
128 	if (struct_size(cmd, out_buf, cmd->in_length) > buf_len)
129 		return -EINVAL;
130 
131 	get_lsa = (struct cxl_mbox_get_lsa) {
132 		.offset = cpu_to_le32(cmd->in_offset),
133 		.length = cpu_to_le32(cmd->in_length),
134 	};
135 	mbox_cmd = (struct cxl_mbox_cmd) {
136 		.opcode = CXL_MBOX_OP_GET_LSA,
137 		.payload_in = &get_lsa,
138 		.size_in = sizeof(get_lsa),
139 		.size_out = cmd->in_length,
140 		.payload_out = cmd->out_buf,
141 	};
142 
143 	rc = cxl_internal_send_cmd(cxlds, &mbox_cmd);
144 	cmd->status = 0;
145 
146 	return rc;
147 }
148 
149 static int cxl_pmem_set_config_data(struct cxl_dev_state *cxlds,
150 				    struct nd_cmd_set_config_hdr *cmd,
151 				    unsigned int buf_len)
152 {
153 	struct cxl_mbox_set_lsa *set_lsa;
154 	struct cxl_mbox_cmd mbox_cmd;
155 	int rc;
156 
157 	if (sizeof(*cmd) > buf_len)
158 		return -EINVAL;
159 
160 	/* 4-byte status follows the input data in the payload */
161 	if (size_add(struct_size(cmd, in_buf, cmd->in_length), 4) > buf_len)
162 		return -EINVAL;
163 
164 	set_lsa =
165 		kvzalloc(struct_size(set_lsa, data, cmd->in_length), GFP_KERNEL);
166 	if (!set_lsa)
167 		return -ENOMEM;
168 
169 	*set_lsa = (struct cxl_mbox_set_lsa) {
170 		.offset = cpu_to_le32(cmd->in_offset),
171 	};
172 	memcpy(set_lsa->data, cmd->in_buf, cmd->in_length);
173 	mbox_cmd = (struct cxl_mbox_cmd) {
174 		.opcode = CXL_MBOX_OP_SET_LSA,
175 		.payload_in = set_lsa,
176 		.size_in = struct_size(set_lsa, data, cmd->in_length),
177 	};
178 
179 	rc = cxl_internal_send_cmd(cxlds, &mbox_cmd);
180 
181 	/*
182 	 * Set "firmware" status (4-packed bytes at the end of the input
183 	 * payload.
184 	 */
185 	put_unaligned(0, (u32 *) &cmd->in_buf[cmd->in_length]);
186 	kvfree(set_lsa);
187 
188 	return rc;
189 }
190 
191 static int cxl_pmem_nvdimm_ctl(struct nvdimm *nvdimm, unsigned int cmd,
192 			       void *buf, unsigned int buf_len)
193 {
194 	struct cxl_nvdimm *cxl_nvd = nvdimm_provider_data(nvdimm);
195 	unsigned long cmd_mask = nvdimm_cmd_mask(nvdimm);
196 	struct cxl_memdev *cxlmd = cxl_nvd->cxlmd;
197 	struct cxl_dev_state *cxlds = cxlmd->cxlds;
198 
199 	if (!test_bit(cmd, &cmd_mask))
200 		return -ENOTTY;
201 
202 	switch (cmd) {
203 	case ND_CMD_GET_CONFIG_SIZE:
204 		return cxl_pmem_get_config_size(cxlds, buf, buf_len);
205 	case ND_CMD_GET_CONFIG_DATA:
206 		return cxl_pmem_get_config_data(cxlds, buf, buf_len);
207 	case ND_CMD_SET_CONFIG_DATA:
208 		return cxl_pmem_set_config_data(cxlds, buf, buf_len);
209 	default:
210 		return -ENOTTY;
211 	}
212 }
213 
214 static int cxl_pmem_ctl(struct nvdimm_bus_descriptor *nd_desc,
215 			struct nvdimm *nvdimm, unsigned int cmd, void *buf,
216 			unsigned int buf_len, int *cmd_rc)
217 {
218 	/*
219 	 * No firmware response to translate, let the transport error
220 	 * code take precedence.
221 	 */
222 	*cmd_rc = 0;
223 
224 	if (!nvdimm)
225 		return -ENOTTY;
226 	return cxl_pmem_nvdimm_ctl(nvdimm, cmd, buf, buf_len);
227 }
228 
229 static int detach_nvdimm(struct device *dev, void *data)
230 {
231 	struct cxl_nvdimm *cxl_nvd;
232 	bool release = false;
233 
234 	if (!is_cxl_nvdimm(dev))
235 		return 0;
236 
237 	device_lock(dev);
238 	if (!dev->driver)
239 		goto out;
240 
241 	cxl_nvd = to_cxl_nvdimm(dev);
242 	if (cxl_nvd->cxlmd && cxl_nvd->cxlmd->cxl_nvb == data)
243 		release = true;
244 out:
245 	device_unlock(dev);
246 	if (release)
247 		device_release_driver(dev);
248 	return 0;
249 }
250 
251 static void unregister_nvdimm_bus(void *_cxl_nvb)
252 {
253 	struct cxl_nvdimm_bridge *cxl_nvb = _cxl_nvb;
254 	struct nvdimm_bus *nvdimm_bus = cxl_nvb->nvdimm_bus;
255 
256 	bus_for_each_dev(&cxl_bus_type, NULL, cxl_nvb, detach_nvdimm);
257 
258 	cxl_nvb->nvdimm_bus = NULL;
259 	nvdimm_bus_unregister(nvdimm_bus);
260 }
261 
262 static int cxl_nvdimm_bridge_probe(struct device *dev)
263 {
264 	struct cxl_nvdimm_bridge *cxl_nvb = to_cxl_nvdimm_bridge(dev);
265 
266 	cxl_nvb->nd_desc = (struct nvdimm_bus_descriptor) {
267 		.provider_name = "CXL",
268 		.module = THIS_MODULE,
269 		.ndctl = cxl_pmem_ctl,
270 	};
271 
272 	cxl_nvb->nvdimm_bus =
273 		nvdimm_bus_register(&cxl_nvb->dev, &cxl_nvb->nd_desc);
274 
275 	if (!cxl_nvb->nvdimm_bus)
276 		return -ENOMEM;
277 
278 	return devm_add_action_or_reset(dev, unregister_nvdimm_bus, cxl_nvb);
279 }
280 
281 static struct cxl_driver cxl_nvdimm_bridge_driver = {
282 	.name = "cxl_nvdimm_bridge",
283 	.probe = cxl_nvdimm_bridge_probe,
284 	.id = CXL_DEVICE_NVDIMM_BRIDGE,
285 	.drv = {
286 		.suppress_bind_attrs = true,
287 	},
288 };
289 
290 static void unregister_nvdimm_region(void *nd_region)
291 {
292 	nvdimm_region_delete(nd_region);
293 }
294 
295 static void cxlr_pmem_remove_resource(void *res)
296 {
297 	remove_resource(res);
298 }
299 
300 struct cxl_pmem_region_info {
301 	u64 offset;
302 	u64 serial;
303 };
304 
305 static int cxl_pmem_region_probe(struct device *dev)
306 {
307 	struct nd_mapping_desc mappings[CXL_DECODER_MAX_INTERLEAVE];
308 	struct cxl_pmem_region *cxlr_pmem = to_cxl_pmem_region(dev);
309 	struct cxl_region *cxlr = cxlr_pmem->cxlr;
310 	struct cxl_nvdimm_bridge *cxl_nvb = cxlr->cxl_nvb;
311 	struct cxl_pmem_region_info *info = NULL;
312 	struct nd_interleave_set *nd_set;
313 	struct nd_region_desc ndr_desc;
314 	struct cxl_nvdimm *cxl_nvd;
315 	struct nvdimm *nvdimm;
316 	struct resource *res;
317 	int rc, i = 0;
318 
319 	memset(&mappings, 0, sizeof(mappings));
320 	memset(&ndr_desc, 0, sizeof(ndr_desc));
321 
322 	res = devm_kzalloc(dev, sizeof(*res), GFP_KERNEL);
323 	if (!res)
324 		return -ENOMEM;
325 
326 	res->name = "Persistent Memory";
327 	res->start = cxlr_pmem->hpa_range.start;
328 	res->end = cxlr_pmem->hpa_range.end;
329 	res->flags = IORESOURCE_MEM;
330 	res->desc = IORES_DESC_PERSISTENT_MEMORY;
331 
332 	rc = insert_resource(&iomem_resource, res);
333 	if (rc)
334 		return rc;
335 
336 	rc = devm_add_action_or_reset(dev, cxlr_pmem_remove_resource, res);
337 	if (rc)
338 		return rc;
339 
340 	ndr_desc.res = res;
341 	ndr_desc.provider_data = cxlr_pmem;
342 
343 	ndr_desc.numa_node = memory_add_physaddr_to_nid(res->start);
344 	ndr_desc.target_node = phys_to_target_node(res->start);
345 	if (ndr_desc.target_node == NUMA_NO_NODE) {
346 		ndr_desc.target_node = ndr_desc.numa_node;
347 		dev_dbg(&cxlr->dev, "changing target node from %d to %d",
348 			NUMA_NO_NODE, ndr_desc.target_node);
349 	}
350 
351 	nd_set = devm_kzalloc(dev, sizeof(*nd_set), GFP_KERNEL);
352 	if (!nd_set)
353 		return -ENOMEM;
354 
355 	ndr_desc.memregion = cxlr->id;
356 	set_bit(ND_REGION_CXL, &ndr_desc.flags);
357 	set_bit(ND_REGION_PERSIST_MEMCTRL, &ndr_desc.flags);
358 
359 	info = kmalloc_array(cxlr_pmem->nr_mappings, sizeof(*info), GFP_KERNEL);
360 	if (!info)
361 		return -ENOMEM;
362 
363 	for (i = 0; i < cxlr_pmem->nr_mappings; i++) {
364 		struct cxl_pmem_region_mapping *m = &cxlr_pmem->mapping[i];
365 		struct cxl_memdev *cxlmd = m->cxlmd;
366 		struct cxl_dev_state *cxlds = cxlmd->cxlds;
367 
368 		cxl_nvd = cxlmd->cxl_nvd;
369 		nvdimm = dev_get_drvdata(&cxl_nvd->dev);
370 		if (!nvdimm) {
371 			dev_dbg(dev, "[%d]: %s: no nvdimm found\n", i,
372 				dev_name(&cxlmd->dev));
373 			rc = -ENODEV;
374 			goto out_nvd;
375 		}
376 
377 		m->cxl_nvd = cxl_nvd;
378 		mappings[i] = (struct nd_mapping_desc) {
379 			.nvdimm = nvdimm,
380 			.start = m->start,
381 			.size = m->size,
382 			.position = i,
383 		};
384 		info[i].offset = m->start;
385 		info[i].serial = cxlds->serial;
386 	}
387 	ndr_desc.num_mappings = cxlr_pmem->nr_mappings;
388 	ndr_desc.mapping = mappings;
389 
390 	/*
391 	 * TODO enable CXL labels which skip the need for 'interleave-set cookie'
392 	 */
393 	nd_set->cookie1 =
394 		nd_fletcher64(info, sizeof(*info) * cxlr_pmem->nr_mappings, 0);
395 	nd_set->cookie2 = nd_set->cookie1;
396 	ndr_desc.nd_set = nd_set;
397 
398 	cxlr_pmem->nd_region =
399 		nvdimm_pmem_region_create(cxl_nvb->nvdimm_bus, &ndr_desc);
400 	if (!cxlr_pmem->nd_region) {
401 		rc = -ENOMEM;
402 		goto out_nvd;
403 	}
404 
405 	rc = devm_add_action_or_reset(dev, unregister_nvdimm_region,
406 				      cxlr_pmem->nd_region);
407 out_nvd:
408 	kfree(info);
409 
410 	return rc;
411 }
412 
413 static struct cxl_driver cxl_pmem_region_driver = {
414 	.name = "cxl_pmem_region",
415 	.probe = cxl_pmem_region_probe,
416 	.id = CXL_DEVICE_PMEM_REGION,
417 	.drv = {
418 		.suppress_bind_attrs = true,
419 	},
420 };
421 
422 static __init int cxl_pmem_init(void)
423 {
424 	int rc;
425 
426 	set_bit(CXL_MEM_COMMAND_ID_SET_SHUTDOWN_STATE, exclusive_cmds);
427 	set_bit(CXL_MEM_COMMAND_ID_SET_LSA, exclusive_cmds);
428 
429 	rc = cxl_driver_register(&cxl_nvdimm_bridge_driver);
430 	if (rc)
431 		return rc;
432 
433 	rc = cxl_driver_register(&cxl_nvdimm_driver);
434 	if (rc)
435 		goto err_nvdimm;
436 
437 	rc = cxl_driver_register(&cxl_pmem_region_driver);
438 	if (rc)
439 		goto err_region;
440 
441 	return 0;
442 
443 err_region:
444 	cxl_driver_unregister(&cxl_nvdimm_driver);
445 err_nvdimm:
446 	cxl_driver_unregister(&cxl_nvdimm_bridge_driver);
447 	return rc;
448 }
449 
450 static __exit void cxl_pmem_exit(void)
451 {
452 	cxl_driver_unregister(&cxl_pmem_region_driver);
453 	cxl_driver_unregister(&cxl_nvdimm_driver);
454 	cxl_driver_unregister(&cxl_nvdimm_bridge_driver);
455 }
456 
457 MODULE_LICENSE("GPL v2");
458 module_init(cxl_pmem_init);
459 module_exit(cxl_pmem_exit);
460 MODULE_IMPORT_NS(CXL);
461 MODULE_ALIAS_CXL(CXL_DEVICE_NVDIMM_BRIDGE);
462 MODULE_ALIAS_CXL(CXL_DEVICE_NVDIMM);
463 MODULE_ALIAS_CXL(CXL_DEVICE_PMEM_REGION);
464