xref: /openbmc/linux/drivers/cxl/pmem.c (revision e761cc20)
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(ND_CMD_GET_CONFIG_SIZE, &cmd_mask);
80 	set_bit(ND_CMD_GET_CONFIG_DATA, &cmd_mask);
81 	set_bit(ND_CMD_SET_CONFIG_DATA, &cmd_mask);
82 	nvdimm = __nvdimm_create(cxl_nvb->nvdimm_bus, cxl_nvd,
83 				 cxl_dimm_attribute_groups, flags,
84 				 cmd_mask, 0, NULL, cxl_nvd->dev_id,
85 				 cxl_security_ops, NULL);
86 	if (!nvdimm)
87 		return -ENOMEM;
88 
89 	dev_set_drvdata(dev, nvdimm);
90 	return devm_add_action_or_reset(dev, unregister_nvdimm, nvdimm);
91 }
92 
93 static struct cxl_driver cxl_nvdimm_driver = {
94 	.name = "cxl_nvdimm",
95 	.probe = cxl_nvdimm_probe,
96 	.id = CXL_DEVICE_NVDIMM,
97 	.drv = {
98 		.suppress_bind_attrs = true,
99 	},
100 };
101 
102 static int cxl_pmem_get_config_size(struct cxl_dev_state *cxlds,
103 				    struct nd_cmd_get_config_size *cmd,
104 				    unsigned int buf_len)
105 {
106 	if (sizeof(*cmd) > buf_len)
107 		return -EINVAL;
108 
109 	*cmd = (struct nd_cmd_get_config_size) {
110 		 .config_size = cxlds->lsa_size,
111 		 .max_xfer = cxlds->payload_size - sizeof(struct cxl_mbox_set_lsa),
112 	};
113 
114 	return 0;
115 }
116 
117 static int cxl_pmem_get_config_data(struct cxl_dev_state *cxlds,
118 				    struct nd_cmd_get_config_data_hdr *cmd,
119 				    unsigned int buf_len)
120 {
121 	struct cxl_mbox_get_lsa get_lsa;
122 	struct cxl_mbox_cmd mbox_cmd;
123 	int rc;
124 
125 	if (sizeof(*cmd) > buf_len)
126 		return -EINVAL;
127 	if (struct_size(cmd, out_buf, cmd->in_length) > buf_len)
128 		return -EINVAL;
129 
130 	get_lsa = (struct cxl_mbox_get_lsa) {
131 		.offset = cpu_to_le32(cmd->in_offset),
132 		.length = cpu_to_le32(cmd->in_length),
133 	};
134 	mbox_cmd = (struct cxl_mbox_cmd) {
135 		.opcode = CXL_MBOX_OP_GET_LSA,
136 		.payload_in = &get_lsa,
137 		.size_in = sizeof(get_lsa),
138 		.size_out = cmd->in_length,
139 		.payload_out = cmd->out_buf,
140 	};
141 
142 	rc = cxl_internal_send_cmd(cxlds, &mbox_cmd);
143 	cmd->status = 0;
144 
145 	return rc;
146 }
147 
148 static int cxl_pmem_set_config_data(struct cxl_dev_state *cxlds,
149 				    struct nd_cmd_set_config_hdr *cmd,
150 				    unsigned int buf_len)
151 {
152 	struct cxl_mbox_set_lsa *set_lsa;
153 	struct cxl_mbox_cmd mbox_cmd;
154 	int rc;
155 
156 	if (sizeof(*cmd) > buf_len)
157 		return -EINVAL;
158 
159 	/* 4-byte status follows the input data in the payload */
160 	if (size_add(struct_size(cmd, in_buf, cmd->in_length), 4) > buf_len)
161 		return -EINVAL;
162 
163 	set_lsa =
164 		kvzalloc(struct_size(set_lsa, data, cmd->in_length), GFP_KERNEL);
165 	if (!set_lsa)
166 		return -ENOMEM;
167 
168 	*set_lsa = (struct cxl_mbox_set_lsa) {
169 		.offset = cpu_to_le32(cmd->in_offset),
170 	};
171 	memcpy(set_lsa->data, cmd->in_buf, cmd->in_length);
172 	mbox_cmd = (struct cxl_mbox_cmd) {
173 		.opcode = CXL_MBOX_OP_SET_LSA,
174 		.payload_in = set_lsa,
175 		.size_in = struct_size(set_lsa, data, cmd->in_length),
176 	};
177 
178 	rc = cxl_internal_send_cmd(cxlds, &mbox_cmd);
179 
180 	/*
181 	 * Set "firmware" status (4-packed bytes at the end of the input
182 	 * payload.
183 	 */
184 	put_unaligned(0, (u32 *) &cmd->in_buf[cmd->in_length]);
185 	kvfree(set_lsa);
186 
187 	return rc;
188 }
189 
190 static int cxl_pmem_nvdimm_ctl(struct nvdimm *nvdimm, unsigned int cmd,
191 			       void *buf, unsigned int buf_len)
192 {
193 	struct cxl_nvdimm *cxl_nvd = nvdimm_provider_data(nvdimm);
194 	unsigned long cmd_mask = nvdimm_cmd_mask(nvdimm);
195 	struct cxl_memdev *cxlmd = cxl_nvd->cxlmd;
196 	struct cxl_dev_state *cxlds = cxlmd->cxlds;
197 
198 	if (!test_bit(cmd, &cmd_mask))
199 		return -ENOTTY;
200 
201 	switch (cmd) {
202 	case ND_CMD_GET_CONFIG_SIZE:
203 		return cxl_pmem_get_config_size(cxlds, buf, buf_len);
204 	case ND_CMD_GET_CONFIG_DATA:
205 		return cxl_pmem_get_config_data(cxlds, buf, buf_len);
206 	case ND_CMD_SET_CONFIG_DATA:
207 		return cxl_pmem_set_config_data(cxlds, buf, buf_len);
208 	default:
209 		return -ENOTTY;
210 	}
211 }
212 
213 static int cxl_pmem_ctl(struct nvdimm_bus_descriptor *nd_desc,
214 			struct nvdimm *nvdimm, unsigned int cmd, void *buf,
215 			unsigned int buf_len, int *cmd_rc)
216 {
217 	/*
218 	 * No firmware response to translate, let the transport error
219 	 * code take precedence.
220 	 */
221 	*cmd_rc = 0;
222 
223 	if (!nvdimm)
224 		return -ENOTTY;
225 	return cxl_pmem_nvdimm_ctl(nvdimm, cmd, buf, buf_len);
226 }
227 
228 static int detach_nvdimm(struct device *dev, void *data)
229 {
230 	struct cxl_nvdimm *cxl_nvd;
231 	bool release = false;
232 
233 	if (!is_cxl_nvdimm(dev))
234 		return 0;
235 
236 	device_lock(dev);
237 	if (!dev->driver)
238 		goto out;
239 
240 	cxl_nvd = to_cxl_nvdimm(dev);
241 	if (cxl_nvd->cxlmd && cxl_nvd->cxlmd->cxl_nvb == data)
242 		release = true;
243 out:
244 	device_unlock(dev);
245 	if (release)
246 		device_release_driver(dev);
247 	return 0;
248 }
249 
250 static void unregister_nvdimm_bus(void *_cxl_nvb)
251 {
252 	struct cxl_nvdimm_bridge *cxl_nvb = _cxl_nvb;
253 	struct nvdimm_bus *nvdimm_bus = cxl_nvb->nvdimm_bus;
254 
255 	bus_for_each_dev(&cxl_bus_type, NULL, cxl_nvb, detach_nvdimm);
256 
257 	cxl_nvb->nvdimm_bus = NULL;
258 	nvdimm_bus_unregister(nvdimm_bus);
259 }
260 
261 static int cxl_nvdimm_bridge_probe(struct device *dev)
262 {
263 	struct cxl_nvdimm_bridge *cxl_nvb = to_cxl_nvdimm_bridge(dev);
264 
265 	cxl_nvb->nd_desc = (struct nvdimm_bus_descriptor) {
266 		.provider_name = "CXL",
267 		.module = THIS_MODULE,
268 		.ndctl = cxl_pmem_ctl,
269 	};
270 
271 	cxl_nvb->nvdimm_bus =
272 		nvdimm_bus_register(&cxl_nvb->dev, &cxl_nvb->nd_desc);
273 
274 	if (!cxl_nvb->nvdimm_bus)
275 		return -ENOMEM;
276 
277 	return devm_add_action_or_reset(dev, unregister_nvdimm_bus, cxl_nvb);
278 }
279 
280 static struct cxl_driver cxl_nvdimm_bridge_driver = {
281 	.name = "cxl_nvdimm_bridge",
282 	.probe = cxl_nvdimm_bridge_probe,
283 	.id = CXL_DEVICE_NVDIMM_BRIDGE,
284 	.drv = {
285 		.suppress_bind_attrs = true,
286 	},
287 };
288 
289 static void unregister_nvdimm_region(void *nd_region)
290 {
291 	nvdimm_region_delete(nd_region);
292 }
293 
294 static void cxlr_pmem_remove_resource(void *res)
295 {
296 	remove_resource(res);
297 }
298 
299 struct cxl_pmem_region_info {
300 	u64 offset;
301 	u64 serial;
302 };
303 
304 static int cxl_pmem_region_probe(struct device *dev)
305 {
306 	struct nd_mapping_desc mappings[CXL_DECODER_MAX_INTERLEAVE];
307 	struct cxl_pmem_region *cxlr_pmem = to_cxl_pmem_region(dev);
308 	struct cxl_region *cxlr = cxlr_pmem->cxlr;
309 	struct cxl_nvdimm_bridge *cxl_nvb = cxlr->cxl_nvb;
310 	struct cxl_pmem_region_info *info = NULL;
311 	struct nd_interleave_set *nd_set;
312 	struct nd_region_desc ndr_desc;
313 	struct cxl_nvdimm *cxl_nvd;
314 	struct nvdimm *nvdimm;
315 	struct resource *res;
316 	int rc, i = 0;
317 
318 	memset(&mappings, 0, sizeof(mappings));
319 	memset(&ndr_desc, 0, sizeof(ndr_desc));
320 
321 	res = devm_kzalloc(dev, sizeof(*res), GFP_KERNEL);
322 	if (!res)
323 		return -ENOMEM;
324 
325 	res->name = "Persistent Memory";
326 	res->start = cxlr_pmem->hpa_range.start;
327 	res->end = cxlr_pmem->hpa_range.end;
328 	res->flags = IORESOURCE_MEM;
329 	res->desc = IORES_DESC_PERSISTENT_MEMORY;
330 
331 	rc = insert_resource(&iomem_resource, res);
332 	if (rc)
333 		return rc;
334 
335 	rc = devm_add_action_or_reset(dev, cxlr_pmem_remove_resource, res);
336 	if (rc)
337 		return rc;
338 
339 	ndr_desc.res = res;
340 	ndr_desc.provider_data = cxlr_pmem;
341 
342 	ndr_desc.numa_node = memory_add_physaddr_to_nid(res->start);
343 	ndr_desc.target_node = phys_to_target_node(res->start);
344 	if (ndr_desc.target_node == NUMA_NO_NODE) {
345 		ndr_desc.target_node = ndr_desc.numa_node;
346 		dev_dbg(&cxlr->dev, "changing target node from %d to %d",
347 			NUMA_NO_NODE, ndr_desc.target_node);
348 	}
349 
350 	nd_set = devm_kzalloc(dev, sizeof(*nd_set), GFP_KERNEL);
351 	if (!nd_set)
352 		return -ENOMEM;
353 
354 	ndr_desc.memregion = cxlr->id;
355 	set_bit(ND_REGION_CXL, &ndr_desc.flags);
356 	set_bit(ND_REGION_PERSIST_MEMCTRL, &ndr_desc.flags);
357 
358 	info = kmalloc_array(cxlr_pmem->nr_mappings, sizeof(*info), GFP_KERNEL);
359 	if (!info)
360 		return -ENOMEM;
361 
362 	for (i = 0; i < cxlr_pmem->nr_mappings; i++) {
363 		struct cxl_pmem_region_mapping *m = &cxlr_pmem->mapping[i];
364 		struct cxl_memdev *cxlmd = m->cxlmd;
365 		struct cxl_dev_state *cxlds = cxlmd->cxlds;
366 
367 		cxl_nvd = cxlmd->cxl_nvd;
368 		nvdimm = dev_get_drvdata(&cxl_nvd->dev);
369 		if (!nvdimm) {
370 			dev_dbg(dev, "[%d]: %s: no nvdimm found\n", i,
371 				dev_name(&cxlmd->dev));
372 			rc = -ENODEV;
373 			goto out_nvd;
374 		}
375 
376 		m->cxl_nvd = cxl_nvd;
377 		mappings[i] = (struct nd_mapping_desc) {
378 			.nvdimm = nvdimm,
379 			.start = m->start,
380 			.size = m->size,
381 			.position = i,
382 		};
383 		info[i].offset = m->start;
384 		info[i].serial = cxlds->serial;
385 	}
386 	ndr_desc.num_mappings = cxlr_pmem->nr_mappings;
387 	ndr_desc.mapping = mappings;
388 
389 	/*
390 	 * TODO enable CXL labels which skip the need for 'interleave-set cookie'
391 	 */
392 	nd_set->cookie1 =
393 		nd_fletcher64(info, sizeof(*info) * cxlr_pmem->nr_mappings, 0);
394 	nd_set->cookie2 = nd_set->cookie1;
395 	ndr_desc.nd_set = nd_set;
396 
397 	cxlr_pmem->nd_region =
398 		nvdimm_pmem_region_create(cxl_nvb->nvdimm_bus, &ndr_desc);
399 	if (!cxlr_pmem->nd_region) {
400 		rc = -ENOMEM;
401 		goto out_nvd;
402 	}
403 
404 	rc = devm_add_action_or_reset(dev, unregister_nvdimm_region,
405 				      cxlr_pmem->nd_region);
406 out_nvd:
407 	kfree(info);
408 
409 	return rc;
410 }
411 
412 static struct cxl_driver cxl_pmem_region_driver = {
413 	.name = "cxl_pmem_region",
414 	.probe = cxl_pmem_region_probe,
415 	.id = CXL_DEVICE_PMEM_REGION,
416 	.drv = {
417 		.suppress_bind_attrs = true,
418 	},
419 };
420 
421 static __init int cxl_pmem_init(void)
422 {
423 	int rc;
424 
425 	set_bit(CXL_MEM_COMMAND_ID_SET_SHUTDOWN_STATE, exclusive_cmds);
426 	set_bit(CXL_MEM_COMMAND_ID_SET_LSA, exclusive_cmds);
427 
428 	rc = cxl_driver_register(&cxl_nvdimm_bridge_driver);
429 	if (rc)
430 		return rc;
431 
432 	rc = cxl_driver_register(&cxl_nvdimm_driver);
433 	if (rc)
434 		goto err_nvdimm;
435 
436 	rc = cxl_driver_register(&cxl_pmem_region_driver);
437 	if (rc)
438 		goto err_region;
439 
440 	return 0;
441 
442 err_region:
443 	cxl_driver_unregister(&cxl_nvdimm_driver);
444 err_nvdimm:
445 	cxl_driver_unregister(&cxl_nvdimm_bridge_driver);
446 	return rc;
447 }
448 
449 static __exit void cxl_pmem_exit(void)
450 {
451 	cxl_driver_unregister(&cxl_pmem_region_driver);
452 	cxl_driver_unregister(&cxl_nvdimm_driver);
453 	cxl_driver_unregister(&cxl_nvdimm_bridge_driver);
454 }
455 
456 MODULE_LICENSE("GPL v2");
457 module_init(cxl_pmem_init);
458 module_exit(cxl_pmem_exit);
459 MODULE_IMPORT_NS(CXL);
460 MODULE_ALIAS_CXL(CXL_DEVICE_NVDIMM_BRIDGE);
461 MODULE_ALIAS_CXL(CXL_DEVICE_NVDIMM);
462 MODULE_ALIAS_CXL(CXL_DEVICE_PMEM_REGION);
463