xref: /linux/arch/s390/pci/pci_clp.c (revision c4ee0af3fa0dc65f690fc908f02b8355f9576ea0)
1 /*
2  * Copyright IBM Corp. 2012
3  *
4  * Author(s):
5  *   Jan Glauber <jang@linux.vnet.ibm.com>
6  */
7 
8 #define COMPONENT "zPCI"
9 #define pr_fmt(fmt) COMPONENT ": " fmt
10 
11 #include <linux/kernel.h>
12 #include <linux/slab.h>
13 #include <linux/err.h>
14 #include <linux/delay.h>
15 #include <linux/pci.h>
16 #include <asm/pci_debug.h>
17 #include <asm/pci_clp.h>
18 
19 static inline void zpci_err_clp(unsigned int rsp, int rc)
20 {
21 	struct {
22 		unsigned int rsp;
23 		int rc;
24 	} __packed data = {rsp, rc};
25 
26 	zpci_err_hex(&data, sizeof(data));
27 }
28 
29 /*
30  * Call Logical Processor
31  * Retry logic is handled by the caller.
32  */
33 static inline u8 clp_instr(void *data)
34 {
35 	struct { u8 _[CLP_BLK_SIZE]; } *req = data;
36 	u64 ignored;
37 	u8 cc;
38 
39 	asm volatile (
40 		"	.insn	rrf,0xb9a00000,%[ign],%[req],0x0,0x2\n"
41 		"	ipm	%[cc]\n"
42 		"	srl	%[cc],28\n"
43 		: [cc] "=d" (cc), [ign] "=d" (ignored), "+m" (*req)
44 		: [req] "a" (req)
45 		: "cc");
46 	return cc;
47 }
48 
49 static void *clp_alloc_block(gfp_t gfp_mask)
50 {
51 	return (void *) __get_free_pages(gfp_mask, get_order(CLP_BLK_SIZE));
52 }
53 
54 static void clp_free_block(void *ptr)
55 {
56 	free_pages((unsigned long) ptr, get_order(CLP_BLK_SIZE));
57 }
58 
59 static void clp_store_query_pci_fngrp(struct zpci_dev *zdev,
60 				      struct clp_rsp_query_pci_grp *response)
61 {
62 	zdev->tlb_refresh = response->refresh;
63 	zdev->dma_mask = response->dasm;
64 	zdev->msi_addr = response->msia;
65 	zdev->fmb_update = response->mui;
66 
67 	switch (response->version) {
68 	case 1:
69 		zdev->max_bus_speed = PCIE_SPEED_5_0GT;
70 		break;
71 	default:
72 		zdev->max_bus_speed = PCI_SPEED_UNKNOWN;
73 		break;
74 	}
75 }
76 
77 static int clp_query_pci_fngrp(struct zpci_dev *zdev, u8 pfgid)
78 {
79 	struct clp_req_rsp_query_pci_grp *rrb;
80 	int rc;
81 
82 	rrb = clp_alloc_block(GFP_KERNEL);
83 	if (!rrb)
84 		return -ENOMEM;
85 
86 	memset(rrb, 0, sizeof(*rrb));
87 	rrb->request.hdr.len = sizeof(rrb->request);
88 	rrb->request.hdr.cmd = CLP_QUERY_PCI_FNGRP;
89 	rrb->response.hdr.len = sizeof(rrb->response);
90 	rrb->request.pfgid = pfgid;
91 
92 	rc = clp_instr(rrb);
93 	if (!rc && rrb->response.hdr.rsp == CLP_RC_OK)
94 		clp_store_query_pci_fngrp(zdev, &rrb->response);
95 	else {
96 		zpci_err("Q PCI FGRP:\n");
97 		zpci_err_clp(rrb->response.hdr.rsp, rc);
98 		rc = -EIO;
99 	}
100 	clp_free_block(rrb);
101 	return rc;
102 }
103 
104 static int clp_store_query_pci_fn(struct zpci_dev *zdev,
105 				  struct clp_rsp_query_pci *response)
106 {
107 	int i;
108 
109 	for (i = 0; i < PCI_BAR_COUNT; i++) {
110 		zdev->bars[i].val = le32_to_cpu(response->bar[i]);
111 		zdev->bars[i].size = response->bar_size[i];
112 	}
113 	zdev->start_dma = response->sdma;
114 	zdev->end_dma = response->edma;
115 	zdev->pchid = response->pchid;
116 	zdev->pfgid = response->pfgid;
117 	return 0;
118 }
119 
120 static int clp_query_pci_fn(struct zpci_dev *zdev, u32 fh)
121 {
122 	struct clp_req_rsp_query_pci *rrb;
123 	int rc;
124 
125 	rrb = clp_alloc_block(GFP_KERNEL);
126 	if (!rrb)
127 		return -ENOMEM;
128 
129 	memset(rrb, 0, sizeof(*rrb));
130 	rrb->request.hdr.len = sizeof(rrb->request);
131 	rrb->request.hdr.cmd = CLP_QUERY_PCI_FN;
132 	rrb->response.hdr.len = sizeof(rrb->response);
133 	rrb->request.fh = fh;
134 
135 	rc = clp_instr(rrb);
136 	if (!rc && rrb->response.hdr.rsp == CLP_RC_OK) {
137 		rc = clp_store_query_pci_fn(zdev, &rrb->response);
138 		if (rc)
139 			goto out;
140 		if (rrb->response.pfgid)
141 			rc = clp_query_pci_fngrp(zdev, rrb->response.pfgid);
142 	} else {
143 		zpci_err("Q PCI FN:\n");
144 		zpci_err_clp(rrb->response.hdr.rsp, rc);
145 		rc = -EIO;
146 	}
147 out:
148 	clp_free_block(rrb);
149 	return rc;
150 }
151 
152 int clp_add_pci_device(u32 fid, u32 fh, int configured)
153 {
154 	struct zpci_dev *zdev;
155 	int rc;
156 
157 	zpci_dbg(3, "add fid:%x, fh:%x, c:%d\n", fid, fh, configured);
158 	zdev = kzalloc(sizeof(*zdev), GFP_KERNEL);
159 	if (!zdev)
160 		return -ENOMEM;
161 
162 	zdev->fh = fh;
163 	zdev->fid = fid;
164 
165 	/* Query function properties and update zdev */
166 	rc = clp_query_pci_fn(zdev, fh);
167 	if (rc)
168 		goto error;
169 
170 	if (configured)
171 		zdev->state = ZPCI_FN_STATE_CONFIGURED;
172 	else
173 		zdev->state = ZPCI_FN_STATE_STANDBY;
174 
175 	rc = zpci_create_device(zdev);
176 	if (rc)
177 		goto error;
178 	return 0;
179 
180 error:
181 	kfree(zdev);
182 	return rc;
183 }
184 
185 /*
186  * Enable/Disable a given PCI function defined by its function handle.
187  */
188 static int clp_set_pci_fn(u32 *fh, u8 nr_dma_as, u8 command)
189 {
190 	struct clp_req_rsp_set_pci *rrb;
191 	int rc, retries = 100;
192 
193 	rrb = clp_alloc_block(GFP_KERNEL);
194 	if (!rrb)
195 		return -ENOMEM;
196 
197 	do {
198 		memset(rrb, 0, sizeof(*rrb));
199 		rrb->request.hdr.len = sizeof(rrb->request);
200 		rrb->request.hdr.cmd = CLP_SET_PCI_FN;
201 		rrb->response.hdr.len = sizeof(rrb->response);
202 		rrb->request.fh = *fh;
203 		rrb->request.oc = command;
204 		rrb->request.ndas = nr_dma_as;
205 
206 		rc = clp_instr(rrb);
207 		if (rrb->response.hdr.rsp == CLP_RC_SETPCIFN_BUSY) {
208 			retries--;
209 			if (retries < 0)
210 				break;
211 			msleep(20);
212 		}
213 	} while (rrb->response.hdr.rsp == CLP_RC_SETPCIFN_BUSY);
214 
215 	if (!rc && rrb->response.hdr.rsp == CLP_RC_OK)
216 		*fh = rrb->response.fh;
217 	else {
218 		zpci_err("Set PCI FN:\n");
219 		zpci_err_clp(rrb->response.hdr.rsp, rc);
220 		rc = -EIO;
221 	}
222 	clp_free_block(rrb);
223 	return rc;
224 }
225 
226 int clp_enable_fh(struct zpci_dev *zdev, u8 nr_dma_as)
227 {
228 	u32 fh = zdev->fh;
229 	int rc;
230 
231 	rc = clp_set_pci_fn(&fh, nr_dma_as, CLP_SET_ENABLE_PCI_FN);
232 	if (!rc)
233 		/* Success -> store enabled handle in zdev */
234 		zdev->fh = fh;
235 
236 	zpci_dbg(3, "ena fid:%x, fh:%x, rc:%d\n", zdev->fid, zdev->fh, rc);
237 	return rc;
238 }
239 
240 int clp_disable_fh(struct zpci_dev *zdev)
241 {
242 	u32 fh = zdev->fh;
243 	int rc;
244 
245 	if (!zdev_enabled(zdev))
246 		return 0;
247 
248 	rc = clp_set_pci_fn(&fh, 0, CLP_SET_DISABLE_PCI_FN);
249 	if (!rc)
250 		/* Success -> store disabled handle in zdev */
251 		zdev->fh = fh;
252 
253 	zpci_dbg(3, "dis fid:%x, fh:%x, rc:%d\n", zdev->fid, zdev->fh, rc);
254 	return rc;
255 }
256 
257 static int clp_list_pci(struct clp_req_rsp_list_pci *rrb,
258 			void (*cb)(struct clp_fh_list_entry *entry))
259 {
260 	u64 resume_token = 0;
261 	int entries, i, rc;
262 
263 	do {
264 		memset(rrb, 0, sizeof(*rrb));
265 		rrb->request.hdr.len = sizeof(rrb->request);
266 		rrb->request.hdr.cmd = CLP_LIST_PCI;
267 		/* store as many entries as possible */
268 		rrb->response.hdr.len = CLP_BLK_SIZE - LIST_PCI_HDR_LEN;
269 		rrb->request.resume_token = resume_token;
270 
271 		/* Get PCI function handle list */
272 		rc = clp_instr(rrb);
273 		if (rc || rrb->response.hdr.rsp != CLP_RC_OK) {
274 			zpci_err("List PCI FN:\n");
275 			zpci_err_clp(rrb->response.hdr.rsp, rc);
276 			rc = -EIO;
277 			goto out;
278 		}
279 
280 		WARN_ON_ONCE(rrb->response.entry_size !=
281 			sizeof(struct clp_fh_list_entry));
282 
283 		entries = (rrb->response.hdr.len - LIST_PCI_HDR_LEN) /
284 			rrb->response.entry_size;
285 
286 		resume_token = rrb->response.resume_token;
287 		for (i = 0; i < entries; i++)
288 			cb(&rrb->response.fh_list[i]);
289 	} while (resume_token);
290 out:
291 	return rc;
292 }
293 
294 static void __clp_add(struct clp_fh_list_entry *entry)
295 {
296 	if (!entry->vendor_id)
297 		return;
298 
299 	clp_add_pci_device(entry->fid, entry->fh, entry->config_state);
300 }
301 
302 static void __clp_rescan(struct clp_fh_list_entry *entry)
303 {
304 	struct zpci_dev *zdev;
305 
306 	if (!entry->vendor_id)
307 		return;
308 
309 	zdev = get_zdev_by_fid(entry->fid);
310 	if (!zdev) {
311 		clp_add_pci_device(entry->fid, entry->fh, entry->config_state);
312 		return;
313 	}
314 
315 	if (!entry->config_state) {
316 		/*
317 		 * The handle is already disabled, that means no iota/irq freeing via
318 		 * the firmware interfaces anymore. Need to free resources manually
319 		 * (DMA memory, debug, sysfs)...
320 		 */
321 		zpci_stop_device(zdev);
322 	}
323 }
324 
325 static void __clp_update(struct clp_fh_list_entry *entry)
326 {
327 	struct zpci_dev *zdev;
328 
329 	if (!entry->vendor_id)
330 		return;
331 
332 	zdev = get_zdev_by_fid(entry->fid);
333 	if (!zdev)
334 		return;
335 
336 	zdev->fh = entry->fh;
337 }
338 
339 int clp_scan_pci_devices(void)
340 {
341 	struct clp_req_rsp_list_pci *rrb;
342 	int rc;
343 
344 	rrb = clp_alloc_block(GFP_KERNEL);
345 	if (!rrb)
346 		return -ENOMEM;
347 
348 	rc = clp_list_pci(rrb, __clp_add);
349 
350 	clp_free_block(rrb);
351 	return rc;
352 }
353 
354 int clp_rescan_pci_devices(void)
355 {
356 	struct clp_req_rsp_list_pci *rrb;
357 	int rc;
358 
359 	rrb = clp_alloc_block(GFP_KERNEL);
360 	if (!rrb)
361 		return -ENOMEM;
362 
363 	rc = clp_list_pci(rrb, __clp_rescan);
364 
365 	clp_free_block(rrb);
366 	return rc;
367 }
368 
369 int clp_rescan_pci_devices_simple(void)
370 {
371 	struct clp_req_rsp_list_pci *rrb;
372 	int rc;
373 
374 	rrb = clp_alloc_block(GFP_NOWAIT);
375 	if (!rrb)
376 		return -ENOMEM;
377 
378 	rc = clp_list_pci(rrb, __clp_update);
379 
380 	clp_free_block(rrb);
381 	return rc;
382 }
383