xref: /openbmc/linux/drivers/fpga/dfl-pci.c (revision d159037a)
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 #define PCIE_DEVICE_ID_INTEL_PAC_D5005		0x0B2B
77 #define PCIE_DEVICE_ID_SILICOM_PAC_N5010	0x1000
78 #define PCIE_DEVICE_ID_SILICOM_PAC_N5011	0x1001
79 
80 /* VF Device */
81 #define PCIE_DEVICE_ID_VF_INT_5_X		0xBCBF
82 #define PCIE_DEVICE_ID_VF_INT_6_X		0xBCC1
83 #define PCIE_DEVICE_ID_VF_DSC_1_X		0x09C5
84 #define PCIE_DEVICE_ID_INTEL_PAC_D5005_VF	0x0B2C
85 
86 static struct pci_device_id cci_pcie_id_tbl[] = {
87 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCIE_DEVICE_ID_PF_INT_5_X),},
88 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCIE_DEVICE_ID_VF_INT_5_X),},
89 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCIE_DEVICE_ID_PF_INT_6_X),},
90 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCIE_DEVICE_ID_VF_INT_6_X),},
91 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCIE_DEVICE_ID_PF_DSC_1_X),},
92 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCIE_DEVICE_ID_VF_DSC_1_X),},
93 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCIE_DEVICE_ID_INTEL_PAC_N3000),},
94 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCIE_DEVICE_ID_INTEL_PAC_D5005),},
95 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCIE_DEVICE_ID_INTEL_PAC_D5005_VF),},
96 	{PCI_DEVICE(PCI_VENDOR_ID_SILICOM_DENMARK, PCIE_DEVICE_ID_SILICOM_PAC_N5010),},
97 	{PCI_DEVICE(PCI_VENDOR_ID_SILICOM_DENMARK, PCIE_DEVICE_ID_SILICOM_PAC_N5011),},
98 	{0,}
99 };
100 MODULE_DEVICE_TABLE(pci, cci_pcie_id_tbl);
101 
102 static int cci_init_drvdata(struct pci_dev *pcidev)
103 {
104 	struct cci_drvdata *drvdata;
105 
106 	drvdata = devm_kzalloc(&pcidev->dev, sizeof(*drvdata), GFP_KERNEL);
107 	if (!drvdata)
108 		return -ENOMEM;
109 
110 	pci_set_drvdata(pcidev, drvdata);
111 
112 	return 0;
113 }
114 
115 static void cci_remove_feature_devs(struct pci_dev *pcidev)
116 {
117 	struct cci_drvdata *drvdata = pci_get_drvdata(pcidev);
118 
119 	/* remove all children feature devices */
120 	dfl_fpga_feature_devs_remove(drvdata->cdev);
121 	cci_pci_free_irq(pcidev);
122 }
123 
124 static int *cci_pci_create_irq_table(struct pci_dev *pcidev, unsigned int nvec)
125 {
126 	unsigned int i;
127 	int *table;
128 
129 	table = kcalloc(nvec, sizeof(int), GFP_KERNEL);
130 	if (!table)
131 		return table;
132 
133 	for (i = 0; i < nvec; i++)
134 		table[i] = pci_irq_vector(pcidev, i);
135 
136 	return table;
137 }
138 
139 static int find_dfls_by_vsec(struct pci_dev *pcidev, struct dfl_fpga_enum_info *info)
140 {
141 	u32 bir, offset, vndr_hdr, dfl_cnt, dfl_res;
142 	int dfl_res_off, i, bars, voff = 0;
143 	resource_size_t start, len;
144 
145 	while ((voff = pci_find_next_ext_capability(pcidev, voff, PCI_EXT_CAP_ID_VNDR))) {
146 		vndr_hdr = 0;
147 		pci_read_config_dword(pcidev, voff + PCI_VNDR_HEADER, &vndr_hdr);
148 
149 		if (PCI_VNDR_HEADER_ID(vndr_hdr) == PCI_VSEC_ID_INTEL_DFLS &&
150 		    pcidev->vendor == PCI_VENDOR_ID_INTEL)
151 			break;
152 	}
153 
154 	if (!voff) {
155 		dev_dbg(&pcidev->dev, "%s no DFL VSEC found\n", __func__);
156 		return -ENODEV;
157 	}
158 
159 	dfl_cnt = 0;
160 	pci_read_config_dword(pcidev, voff + PCI_VNDR_DFLS_CNT, &dfl_cnt);
161 	if (dfl_cnt > PCI_STD_NUM_BARS) {
162 		dev_err(&pcidev->dev, "%s too many DFLs %d > %d\n",
163 			__func__, dfl_cnt, PCI_STD_NUM_BARS);
164 		return -EINVAL;
165 	}
166 
167 	dfl_res_off = voff + PCI_VNDR_DFLS_RES;
168 	if (dfl_res_off + (dfl_cnt * sizeof(u32)) > PCI_CFG_SPACE_EXP_SIZE) {
169 		dev_err(&pcidev->dev, "%s DFL VSEC too big for PCIe config space\n",
170 			__func__);
171 		return -EINVAL;
172 	}
173 
174 	for (i = 0, bars = 0; i < dfl_cnt; i++, dfl_res_off += sizeof(u32)) {
175 		dfl_res = GENMASK(31, 0);
176 		pci_read_config_dword(pcidev, dfl_res_off, &dfl_res);
177 
178 		bir = dfl_res & PCI_VNDR_DFLS_RES_BAR_MASK;
179 		if (bir >= PCI_STD_NUM_BARS) {
180 			dev_err(&pcidev->dev, "%s bad bir number %d\n",
181 				__func__, bir);
182 			return -EINVAL;
183 		}
184 
185 		if (bars & BIT(bir)) {
186 			dev_err(&pcidev->dev, "%s DFL for BAR %d already specified\n",
187 				__func__, bir);
188 			return -EINVAL;
189 		}
190 
191 		bars |= BIT(bir);
192 
193 		len = pci_resource_len(pcidev, bir);
194 		offset = dfl_res & PCI_VNDR_DFLS_RES_OFF_MASK;
195 		if (offset >= len) {
196 			dev_err(&pcidev->dev, "%s bad offset %u >= %pa\n",
197 				__func__, offset, &len);
198 			return -EINVAL;
199 		}
200 
201 		dev_dbg(&pcidev->dev, "%s BAR %d offset 0x%x\n", __func__, bir, offset);
202 
203 		len -= offset;
204 
205 		start = pci_resource_start(pcidev, bir) + offset;
206 
207 		dfl_fpga_enum_info_add_dfl(info, start, len);
208 	}
209 
210 	return 0;
211 }
212 
213 /* default method of finding dfls starting at offset 0 of bar 0 */
214 static int find_dfls_by_default(struct pci_dev *pcidev,
215 				struct dfl_fpga_enum_info *info)
216 {
217 	int port_num, bar, i, ret = 0;
218 	resource_size_t start, len;
219 	void __iomem *base;
220 	u32 offset;
221 	u64 v;
222 
223 	/* start to find Device Feature List from Bar 0 */
224 	base = cci_pci_ioremap_bar0(pcidev);
225 	if (!base)
226 		return -ENOMEM;
227 
228 	/*
229 	 * PF device has FME and Ports/AFUs, and VF device only has one
230 	 * Port/AFU. Check them and add related "Device Feature List" info
231 	 * for the next step enumeration.
232 	 */
233 	if (dfl_feature_is_fme(base)) {
234 		start = pci_resource_start(pcidev, 0);
235 		len = pci_resource_len(pcidev, 0);
236 
237 		dfl_fpga_enum_info_add_dfl(info, start, len);
238 
239 		/*
240 		 * find more Device Feature Lists (e.g. Ports) per information
241 		 * indicated by FME module.
242 		 */
243 		v = readq(base + FME_HDR_CAP);
244 		port_num = FIELD_GET(FME_CAP_NUM_PORTS, v);
245 
246 		WARN_ON(port_num > MAX_DFL_FPGA_PORT_NUM);
247 
248 		for (i = 0; i < port_num; i++) {
249 			v = readq(base + FME_HDR_PORT_OFST(i));
250 
251 			/* skip ports which are not implemented. */
252 			if (!(v & FME_PORT_OFST_IMP))
253 				continue;
254 
255 			/*
256 			 * add Port's Device Feature List information for next
257 			 * step enumeration.
258 			 */
259 			bar = FIELD_GET(FME_PORT_OFST_BAR_ID, v);
260 			offset = FIELD_GET(FME_PORT_OFST_DFH_OFST, v);
261 			start = pci_resource_start(pcidev, bar) + offset;
262 			len = pci_resource_len(pcidev, bar) - offset;
263 
264 			dfl_fpga_enum_info_add_dfl(info, start, len);
265 		}
266 	} else if (dfl_feature_is_port(base)) {
267 		start = pci_resource_start(pcidev, 0);
268 		len = pci_resource_len(pcidev, 0);
269 
270 		dfl_fpga_enum_info_add_dfl(info, start, len);
271 	} else {
272 		ret = -ENODEV;
273 	}
274 
275 	/* release I/O mappings for next step enumeration */
276 	pcim_iounmap_regions(pcidev, BIT(0));
277 
278 	return ret;
279 }
280 
281 /* enumerate feature devices under pci device */
282 static int cci_enumerate_feature_devs(struct pci_dev *pcidev)
283 {
284 	struct cci_drvdata *drvdata = pci_get_drvdata(pcidev);
285 	struct dfl_fpga_enum_info *info;
286 	struct dfl_fpga_cdev *cdev;
287 	int nvec, ret = 0;
288 	int *irq_table;
289 
290 	/* allocate enumeration info via pci_dev */
291 	info = dfl_fpga_enum_info_alloc(&pcidev->dev);
292 	if (!info)
293 		return -ENOMEM;
294 
295 	/* add irq info for enumeration if the device support irq */
296 	nvec = cci_pci_alloc_irq(pcidev);
297 	if (nvec < 0) {
298 		dev_err(&pcidev->dev, "Fail to alloc irq %d.\n", nvec);
299 		ret = nvec;
300 		goto enum_info_free_exit;
301 	} else if (nvec) {
302 		irq_table = cci_pci_create_irq_table(pcidev, nvec);
303 		if (!irq_table) {
304 			ret = -ENOMEM;
305 			goto irq_free_exit;
306 		}
307 
308 		ret = dfl_fpga_enum_info_add_irq(info, nvec, irq_table);
309 		kfree(irq_table);
310 		if (ret)
311 			goto irq_free_exit;
312 	}
313 
314 	ret = find_dfls_by_vsec(pcidev, info);
315 	if (ret == -ENODEV)
316 		ret = find_dfls_by_default(pcidev, info);
317 
318 	if (ret)
319 		goto irq_free_exit;
320 
321 	/* start enumeration with prepared enumeration information */
322 	cdev = dfl_fpga_feature_devs_enumerate(info);
323 	if (IS_ERR(cdev)) {
324 		dev_err(&pcidev->dev, "Enumeration failure\n");
325 		ret = PTR_ERR(cdev);
326 		goto irq_free_exit;
327 	}
328 
329 	drvdata->cdev = cdev;
330 
331 irq_free_exit:
332 	if (ret)
333 		cci_pci_free_irq(pcidev);
334 enum_info_free_exit:
335 	dfl_fpga_enum_info_free(info);
336 
337 	return ret;
338 }
339 
340 static
341 int cci_pci_probe(struct pci_dev *pcidev, const struct pci_device_id *pcidevid)
342 {
343 	int ret;
344 
345 	ret = pcim_enable_device(pcidev);
346 	if (ret < 0) {
347 		dev_err(&pcidev->dev, "Failed to enable device %d.\n", ret);
348 		return ret;
349 	}
350 
351 	ret = pci_enable_pcie_error_reporting(pcidev);
352 	if (ret && ret != -EINVAL)
353 		dev_info(&pcidev->dev, "PCIE AER unavailable %d.\n", ret);
354 
355 	pci_set_master(pcidev);
356 
357 	if (!pci_set_dma_mask(pcidev, DMA_BIT_MASK(64))) {
358 		ret = pci_set_consistent_dma_mask(pcidev, DMA_BIT_MASK(64));
359 		if (ret)
360 			goto disable_error_report_exit;
361 	} else if (!pci_set_dma_mask(pcidev, DMA_BIT_MASK(32))) {
362 		ret = pci_set_consistent_dma_mask(pcidev, DMA_BIT_MASK(32));
363 		if (ret)
364 			goto disable_error_report_exit;
365 	} else {
366 		ret = -EIO;
367 		dev_err(&pcidev->dev, "No suitable DMA support available.\n");
368 		goto disable_error_report_exit;
369 	}
370 
371 	ret = cci_init_drvdata(pcidev);
372 	if (ret) {
373 		dev_err(&pcidev->dev, "Fail to init drvdata %d.\n", ret);
374 		goto disable_error_report_exit;
375 	}
376 
377 	ret = cci_enumerate_feature_devs(pcidev);
378 	if (!ret)
379 		return ret;
380 
381 	dev_err(&pcidev->dev, "enumeration failure %d.\n", ret);
382 
383 disable_error_report_exit:
384 	pci_disable_pcie_error_reporting(pcidev);
385 	return ret;
386 }
387 
388 static int cci_pci_sriov_configure(struct pci_dev *pcidev, int num_vfs)
389 {
390 	struct cci_drvdata *drvdata = pci_get_drvdata(pcidev);
391 	struct dfl_fpga_cdev *cdev = drvdata->cdev;
392 
393 	if (!num_vfs) {
394 		/*
395 		 * disable SRIOV and then put released ports back to default
396 		 * PF access mode.
397 		 */
398 		pci_disable_sriov(pcidev);
399 
400 		dfl_fpga_cdev_config_ports_pf(cdev);
401 
402 	} else {
403 		int ret;
404 
405 		/*
406 		 * before enable SRIOV, put released ports into VF access mode
407 		 * first of all.
408 		 */
409 		ret = dfl_fpga_cdev_config_ports_vf(cdev, num_vfs);
410 		if (ret)
411 			return ret;
412 
413 		ret = pci_enable_sriov(pcidev, num_vfs);
414 		if (ret) {
415 			dfl_fpga_cdev_config_ports_pf(cdev);
416 			return ret;
417 		}
418 	}
419 
420 	return num_vfs;
421 }
422 
423 static void cci_pci_remove(struct pci_dev *pcidev)
424 {
425 	if (dev_is_pf(&pcidev->dev))
426 		cci_pci_sriov_configure(pcidev, 0);
427 
428 	cci_remove_feature_devs(pcidev);
429 	pci_disable_pcie_error_reporting(pcidev);
430 }
431 
432 static struct pci_driver cci_pci_driver = {
433 	.name = DRV_NAME,
434 	.id_table = cci_pcie_id_tbl,
435 	.probe = cci_pci_probe,
436 	.remove = cci_pci_remove,
437 	.sriov_configure = cci_pci_sriov_configure,
438 };
439 
440 module_pci_driver(cci_pci_driver);
441 
442 MODULE_DESCRIPTION("FPGA DFL PCIe Device Driver");
443 MODULE_AUTHOR("Intel Corporation");
444 MODULE_LICENSE("GPL v2");
445