xref: /linux/drivers/fpga/dfl-pci.c (revision 6c363eafc4d637ac4bd83d4a7dd06dd3cfbe7c5f)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Driver for FPGA Device Feature List (DFL) PCIe device
4  *
5  * Copyright (C) 2017-2018 Intel Corporation, Inc.
6  *
7  * Authors:
8  *   Zhang Yi <Yi.Z.Zhang@intel.com>
9  *   Xiao Guangrong <guangrong.xiao@linux.intel.com>
10  *   Joseph Grecco <joe.grecco@intel.com>
11  *   Enno Luebbers <enno.luebbers@intel.com>
12  *   Tim Whisonant <tim.whisonant@intel.com>
13  *   Ananda Ravuri <ananda.ravuri@intel.com>
14  *   Henry Mitchel <henry.mitchel@intel.com>
15  */
16 
17 #include <linux/pci.h>
18 #include <linux/types.h>
19 #include <linux/kernel.h>
20 #include <linux/module.h>
21 #include <linux/stddef.h>
22 #include <linux/errno.h>
23 #include <linux/aer.h>
24 
25 #include "dfl.h"
26 
27 #define DRV_VERSION	"0.8"
28 #define DRV_NAME	"dfl-pci"
29 
30 #define PCI_VSEC_ID_INTEL_DFLS 0x43
31 
32 #define PCI_VNDR_DFLS_CNT 0x8
33 #define PCI_VNDR_DFLS_RES 0xc
34 
35 #define PCI_VNDR_DFLS_RES_BAR_MASK GENMASK(2, 0)
36 #define PCI_VNDR_DFLS_RES_OFF_MASK GENMASK(31, 3)
37 
38 struct cci_drvdata {
39 	struct dfl_fpga_cdev *cdev;	/* container device */
40 };
41 
42 static void __iomem *cci_pci_ioremap_bar0(struct pci_dev *pcidev)
43 {
44 	if (pcim_iomap_regions(pcidev, BIT(0), DRV_NAME))
45 		return NULL;
46 
47 	return pcim_iomap_table(pcidev)[0];
48 }
49 
50 static int cci_pci_alloc_irq(struct pci_dev *pcidev)
51 {
52 	int ret, nvec = pci_msix_vec_count(pcidev);
53 
54 	if (nvec <= 0) {
55 		dev_dbg(&pcidev->dev, "fpga interrupt not supported\n");
56 		return 0;
57 	}
58 
59 	ret = pci_alloc_irq_vectors(pcidev, nvec, nvec, PCI_IRQ_MSIX);
60 	if (ret < 0)
61 		return ret;
62 
63 	return nvec;
64 }
65 
66 static void cci_pci_free_irq(struct pci_dev *pcidev)
67 {
68 	pci_free_irq_vectors(pcidev);
69 }
70 
71 /* PCI Device ID */
72 #define PCIE_DEVICE_ID_PF_INT_5_X	0xBCBD
73 #define PCIE_DEVICE_ID_PF_INT_6_X	0xBCC0
74 #define PCIE_DEVICE_ID_PF_DSC_1_X	0x09C4
75 #define PCIE_DEVICE_ID_INTEL_PAC_N3000	0x0B30
76 /* VF Device */
77 #define PCIE_DEVICE_ID_VF_INT_5_X	0xBCBF
78 #define PCIE_DEVICE_ID_VF_INT_6_X	0xBCC1
79 #define PCIE_DEVICE_ID_VF_DSC_1_X	0x09C5
80 
81 static struct pci_device_id cci_pcie_id_tbl[] = {
82 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCIE_DEVICE_ID_PF_INT_5_X),},
83 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCIE_DEVICE_ID_VF_INT_5_X),},
84 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCIE_DEVICE_ID_PF_INT_6_X),},
85 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCIE_DEVICE_ID_VF_INT_6_X),},
86 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCIE_DEVICE_ID_PF_DSC_1_X),},
87 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCIE_DEVICE_ID_VF_DSC_1_X),},
88 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCIE_DEVICE_ID_INTEL_PAC_N3000),},
89 	{0,}
90 };
91 MODULE_DEVICE_TABLE(pci, cci_pcie_id_tbl);
92 
93 static int cci_init_drvdata(struct pci_dev *pcidev)
94 {
95 	struct cci_drvdata *drvdata;
96 
97 	drvdata = devm_kzalloc(&pcidev->dev, sizeof(*drvdata), GFP_KERNEL);
98 	if (!drvdata)
99 		return -ENOMEM;
100 
101 	pci_set_drvdata(pcidev, drvdata);
102 
103 	return 0;
104 }
105 
106 static void cci_remove_feature_devs(struct pci_dev *pcidev)
107 {
108 	struct cci_drvdata *drvdata = pci_get_drvdata(pcidev);
109 
110 	/* remove all children feature devices */
111 	dfl_fpga_feature_devs_remove(drvdata->cdev);
112 	cci_pci_free_irq(pcidev);
113 }
114 
115 static int *cci_pci_create_irq_table(struct pci_dev *pcidev, unsigned int nvec)
116 {
117 	unsigned int i;
118 	int *table;
119 
120 	table = kcalloc(nvec, sizeof(int), GFP_KERNEL);
121 	if (!table)
122 		return table;
123 
124 	for (i = 0; i < nvec; i++)
125 		table[i] = pci_irq_vector(pcidev, i);
126 
127 	return table;
128 }
129 
130 static int find_dfls_by_vsec(struct pci_dev *pcidev, struct dfl_fpga_enum_info *info)
131 {
132 	u32 bir, offset, vndr_hdr, dfl_cnt, dfl_res;
133 	int dfl_res_off, i, bars, voff = 0;
134 	resource_size_t start, len;
135 
136 	while ((voff = pci_find_next_ext_capability(pcidev, voff, PCI_EXT_CAP_ID_VNDR))) {
137 		vndr_hdr = 0;
138 		pci_read_config_dword(pcidev, voff + PCI_VNDR_HEADER, &vndr_hdr);
139 
140 		if (PCI_VNDR_HEADER_ID(vndr_hdr) == PCI_VSEC_ID_INTEL_DFLS &&
141 		    pcidev->vendor == PCI_VENDOR_ID_INTEL)
142 			break;
143 	}
144 
145 	if (!voff) {
146 		dev_dbg(&pcidev->dev, "%s no DFL VSEC found\n", __func__);
147 		return -ENODEV;
148 	}
149 
150 	dfl_cnt = 0;
151 	pci_read_config_dword(pcidev, voff + PCI_VNDR_DFLS_CNT, &dfl_cnt);
152 	if (dfl_cnt > PCI_STD_NUM_BARS) {
153 		dev_err(&pcidev->dev, "%s too many DFLs %d > %d\n",
154 			__func__, dfl_cnt, PCI_STD_NUM_BARS);
155 		return -EINVAL;
156 	}
157 
158 	dfl_res_off = voff + PCI_VNDR_DFLS_RES;
159 	if (dfl_res_off + (dfl_cnt * sizeof(u32)) > PCI_CFG_SPACE_EXP_SIZE) {
160 		dev_err(&pcidev->dev, "%s DFL VSEC too big for PCIe config space\n",
161 			__func__);
162 		return -EINVAL;
163 	}
164 
165 	for (i = 0, bars = 0; i < dfl_cnt; i++, dfl_res_off += sizeof(u32)) {
166 		dfl_res = GENMASK(31, 0);
167 		pci_read_config_dword(pcidev, dfl_res_off, &dfl_res);
168 
169 		bir = dfl_res & PCI_VNDR_DFLS_RES_BAR_MASK;
170 		if (bir >= PCI_STD_NUM_BARS) {
171 			dev_err(&pcidev->dev, "%s bad bir number %d\n",
172 				__func__, bir);
173 			return -EINVAL;
174 		}
175 
176 		if (bars & BIT(bir)) {
177 			dev_err(&pcidev->dev, "%s DFL for BAR %d already specified\n",
178 				__func__, bir);
179 			return -EINVAL;
180 		}
181 
182 		bars |= BIT(bir);
183 
184 		len = pci_resource_len(pcidev, bir);
185 		offset = dfl_res & PCI_VNDR_DFLS_RES_OFF_MASK;
186 		if (offset >= len) {
187 			dev_err(&pcidev->dev, "%s bad offset %u >= %pa\n",
188 				__func__, offset, &len);
189 			return -EINVAL;
190 		}
191 
192 		dev_dbg(&pcidev->dev, "%s BAR %d offset 0x%x\n", __func__, bir, offset);
193 
194 		len -= offset;
195 
196 		start = pci_resource_start(pcidev, bir) + offset;
197 
198 		dfl_fpga_enum_info_add_dfl(info, start, len);
199 	}
200 
201 	return 0;
202 }
203 
204 /* default method of finding dfls starting at offset 0 of bar 0 */
205 static int find_dfls_by_default(struct pci_dev *pcidev,
206 				struct dfl_fpga_enum_info *info)
207 {
208 	int port_num, bar, i, ret = 0;
209 	resource_size_t start, len;
210 	void __iomem *base;
211 	u32 offset;
212 	u64 v;
213 
214 	/* start to find Device Feature List from Bar 0 */
215 	base = cci_pci_ioremap_bar0(pcidev);
216 	if (!base)
217 		return -ENOMEM;
218 
219 	/*
220 	 * PF device has FME and Ports/AFUs, and VF device only has one
221 	 * Port/AFU. Check them and add related "Device Feature List" info
222 	 * for the next step enumeration.
223 	 */
224 	if (dfl_feature_is_fme(base)) {
225 		start = pci_resource_start(pcidev, 0);
226 		len = pci_resource_len(pcidev, 0);
227 
228 		dfl_fpga_enum_info_add_dfl(info, start, len);
229 
230 		/*
231 		 * find more Device Feature Lists (e.g. Ports) per information
232 		 * indicated by FME module.
233 		 */
234 		v = readq(base + FME_HDR_CAP);
235 		port_num = FIELD_GET(FME_CAP_NUM_PORTS, v);
236 
237 		WARN_ON(port_num > MAX_DFL_FPGA_PORT_NUM);
238 
239 		for (i = 0; i < port_num; i++) {
240 			v = readq(base + FME_HDR_PORT_OFST(i));
241 
242 			/* skip ports which are not implemented. */
243 			if (!(v & FME_PORT_OFST_IMP))
244 				continue;
245 
246 			/*
247 			 * add Port's Device Feature List information for next
248 			 * step enumeration.
249 			 */
250 			bar = FIELD_GET(FME_PORT_OFST_BAR_ID, v);
251 			offset = FIELD_GET(FME_PORT_OFST_DFH_OFST, v);
252 			start = pci_resource_start(pcidev, bar) + offset;
253 			len = pci_resource_len(pcidev, bar) - offset;
254 
255 			dfl_fpga_enum_info_add_dfl(info, start, len);
256 		}
257 	} else if (dfl_feature_is_port(base)) {
258 		start = pci_resource_start(pcidev, 0);
259 		len = pci_resource_len(pcidev, 0);
260 
261 		dfl_fpga_enum_info_add_dfl(info, start, len);
262 	} else {
263 		ret = -ENODEV;
264 	}
265 
266 	/* release I/O mappings for next step enumeration */
267 	pcim_iounmap_regions(pcidev, BIT(0));
268 
269 	return ret;
270 }
271 
272 /* enumerate feature devices under pci device */
273 static int cci_enumerate_feature_devs(struct pci_dev *pcidev)
274 {
275 	struct cci_drvdata *drvdata = pci_get_drvdata(pcidev);
276 	struct dfl_fpga_enum_info *info;
277 	struct dfl_fpga_cdev *cdev;
278 	int nvec, ret = 0;
279 	int *irq_table;
280 
281 	/* allocate enumeration info via pci_dev */
282 	info = dfl_fpga_enum_info_alloc(&pcidev->dev);
283 	if (!info)
284 		return -ENOMEM;
285 
286 	/* add irq info for enumeration if the device support irq */
287 	nvec = cci_pci_alloc_irq(pcidev);
288 	if (nvec < 0) {
289 		dev_err(&pcidev->dev, "Fail to alloc irq %d.\n", nvec);
290 		ret = nvec;
291 		goto enum_info_free_exit;
292 	} else if (nvec) {
293 		irq_table = cci_pci_create_irq_table(pcidev, nvec);
294 		if (!irq_table) {
295 			ret = -ENOMEM;
296 			goto irq_free_exit;
297 		}
298 
299 		ret = dfl_fpga_enum_info_add_irq(info, nvec, irq_table);
300 		kfree(irq_table);
301 		if (ret)
302 			goto irq_free_exit;
303 	}
304 
305 	ret = find_dfls_by_vsec(pcidev, info);
306 	if (ret == -ENODEV)
307 		ret = find_dfls_by_default(pcidev, info);
308 
309 	if (ret)
310 		goto irq_free_exit;
311 
312 	/* start enumeration with prepared enumeration information */
313 	cdev = dfl_fpga_feature_devs_enumerate(info);
314 	if (IS_ERR(cdev)) {
315 		dev_err(&pcidev->dev, "Enumeration failure\n");
316 		ret = PTR_ERR(cdev);
317 		goto irq_free_exit;
318 	}
319 
320 	drvdata->cdev = cdev;
321 
322 irq_free_exit:
323 	if (ret)
324 		cci_pci_free_irq(pcidev);
325 enum_info_free_exit:
326 	dfl_fpga_enum_info_free(info);
327 
328 	return ret;
329 }
330 
331 static
332 int cci_pci_probe(struct pci_dev *pcidev, const struct pci_device_id *pcidevid)
333 {
334 	int ret;
335 
336 	ret = pcim_enable_device(pcidev);
337 	if (ret < 0) {
338 		dev_err(&pcidev->dev, "Failed to enable device %d.\n", ret);
339 		return ret;
340 	}
341 
342 	ret = pci_enable_pcie_error_reporting(pcidev);
343 	if (ret && ret != -EINVAL)
344 		dev_info(&pcidev->dev, "PCIE AER unavailable %d.\n", ret);
345 
346 	pci_set_master(pcidev);
347 
348 	if (!pci_set_dma_mask(pcidev, DMA_BIT_MASK(64))) {
349 		ret = pci_set_consistent_dma_mask(pcidev, DMA_BIT_MASK(64));
350 		if (ret)
351 			goto disable_error_report_exit;
352 	} else if (!pci_set_dma_mask(pcidev, DMA_BIT_MASK(32))) {
353 		ret = pci_set_consistent_dma_mask(pcidev, DMA_BIT_MASK(32));
354 		if (ret)
355 			goto disable_error_report_exit;
356 	} else {
357 		ret = -EIO;
358 		dev_err(&pcidev->dev, "No suitable DMA support available.\n");
359 		goto disable_error_report_exit;
360 	}
361 
362 	ret = cci_init_drvdata(pcidev);
363 	if (ret) {
364 		dev_err(&pcidev->dev, "Fail to init drvdata %d.\n", ret);
365 		goto disable_error_report_exit;
366 	}
367 
368 	ret = cci_enumerate_feature_devs(pcidev);
369 	if (!ret)
370 		return ret;
371 
372 	dev_err(&pcidev->dev, "enumeration failure %d.\n", ret);
373 
374 disable_error_report_exit:
375 	pci_disable_pcie_error_reporting(pcidev);
376 	return ret;
377 }
378 
379 static int cci_pci_sriov_configure(struct pci_dev *pcidev, int num_vfs)
380 {
381 	struct cci_drvdata *drvdata = pci_get_drvdata(pcidev);
382 	struct dfl_fpga_cdev *cdev = drvdata->cdev;
383 
384 	if (!num_vfs) {
385 		/*
386 		 * disable SRIOV and then put released ports back to default
387 		 * PF access mode.
388 		 */
389 		pci_disable_sriov(pcidev);
390 
391 		dfl_fpga_cdev_config_ports_pf(cdev);
392 
393 	} else {
394 		int ret;
395 
396 		/*
397 		 * before enable SRIOV, put released ports into VF access mode
398 		 * first of all.
399 		 */
400 		ret = dfl_fpga_cdev_config_ports_vf(cdev, num_vfs);
401 		if (ret)
402 			return ret;
403 
404 		ret = pci_enable_sriov(pcidev, num_vfs);
405 		if (ret) {
406 			dfl_fpga_cdev_config_ports_pf(cdev);
407 			return ret;
408 		}
409 	}
410 
411 	return num_vfs;
412 }
413 
414 static void cci_pci_remove(struct pci_dev *pcidev)
415 {
416 	if (dev_is_pf(&pcidev->dev))
417 		cci_pci_sriov_configure(pcidev, 0);
418 
419 	cci_remove_feature_devs(pcidev);
420 	pci_disable_pcie_error_reporting(pcidev);
421 }
422 
423 static struct pci_driver cci_pci_driver = {
424 	.name = DRV_NAME,
425 	.id_table = cci_pcie_id_tbl,
426 	.probe = cci_pci_probe,
427 	.remove = cci_pci_remove,
428 	.sriov_configure = cci_pci_sriov_configure,
429 };
430 
431 module_pci_driver(cci_pci_driver);
432 
433 MODULE_DESCRIPTION("FPGA DFL PCIe Device Driver");
434 MODULE_AUTHOR("Intel Corporation");
435 MODULE_LICENSE("GPL v2");
436