xref: /openbmc/linux/drivers/fpga/dfl-pci.c (revision 7a2f6f61)
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/dma-mapping.h>
19 #include <linux/types.h>
20 #include <linux/kernel.h>
21 #include <linux/module.h>
22 #include <linux/stddef.h>
23 #include <linux/errno.h>
24 #include <linux/aer.h>
25 
26 #include "dfl.h"
27 
28 #define DRV_VERSION	"0.8"
29 #define DRV_NAME	"dfl-pci"
30 
31 #define PCI_VSEC_ID_INTEL_DFLS 0x43
32 
33 #define PCI_VNDR_DFLS_CNT 0x8
34 #define PCI_VNDR_DFLS_RES 0xc
35 
36 #define PCI_VNDR_DFLS_RES_BAR_MASK GENMASK(2, 0)
37 #define PCI_VNDR_DFLS_RES_OFF_MASK GENMASK(31, 3)
38 
39 struct cci_drvdata {
40 	struct dfl_fpga_cdev *cdev;	/* container device */
41 };
42 
43 static void __iomem *cci_pci_ioremap_bar0(struct pci_dev *pcidev)
44 {
45 	if (pcim_iomap_regions(pcidev, BIT(0), DRV_NAME))
46 		return NULL;
47 
48 	return pcim_iomap_table(pcidev)[0];
49 }
50 
51 static int cci_pci_alloc_irq(struct pci_dev *pcidev)
52 {
53 	int ret, nvec = pci_msix_vec_count(pcidev);
54 
55 	if (nvec <= 0) {
56 		dev_dbg(&pcidev->dev, "fpga interrupt not supported\n");
57 		return 0;
58 	}
59 
60 	ret = pci_alloc_irq_vectors(pcidev, nvec, nvec, PCI_IRQ_MSIX);
61 	if (ret < 0)
62 		return ret;
63 
64 	return nvec;
65 }
66 
67 static void cci_pci_free_irq(struct pci_dev *pcidev)
68 {
69 	pci_free_irq_vectors(pcidev);
70 }
71 
72 /* PCI Device ID */
73 #define PCIE_DEVICE_ID_PF_INT_5_X		0xBCBD
74 #define PCIE_DEVICE_ID_PF_INT_6_X		0xBCC0
75 #define PCIE_DEVICE_ID_PF_DSC_1_X		0x09C4
76 #define PCIE_DEVICE_ID_INTEL_PAC_N3000		0x0B30
77 #define PCIE_DEVICE_ID_INTEL_PAC_D5005		0x0B2B
78 #define PCIE_DEVICE_ID_SILICOM_PAC_N5010	0x1000
79 #define PCIE_DEVICE_ID_SILICOM_PAC_N5011	0x1001
80 
81 /* VF Device */
82 #define PCIE_DEVICE_ID_VF_INT_5_X		0xBCBF
83 #define PCIE_DEVICE_ID_VF_INT_6_X		0xBCC1
84 #define PCIE_DEVICE_ID_VF_DSC_1_X		0x09C5
85 #define PCIE_DEVICE_ID_INTEL_PAC_D5005_VF	0x0B2C
86 
87 static struct pci_device_id cci_pcie_id_tbl[] = {
88 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCIE_DEVICE_ID_PF_INT_5_X),},
89 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCIE_DEVICE_ID_VF_INT_5_X),},
90 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCIE_DEVICE_ID_PF_INT_6_X),},
91 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCIE_DEVICE_ID_VF_INT_6_X),},
92 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCIE_DEVICE_ID_PF_DSC_1_X),},
93 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCIE_DEVICE_ID_VF_DSC_1_X),},
94 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCIE_DEVICE_ID_INTEL_PAC_N3000),},
95 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCIE_DEVICE_ID_INTEL_PAC_D5005),},
96 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCIE_DEVICE_ID_INTEL_PAC_D5005_VF),},
97 	{PCI_DEVICE(PCI_VENDOR_ID_SILICOM_DENMARK, PCIE_DEVICE_ID_SILICOM_PAC_N5010),},
98 	{PCI_DEVICE(PCI_VENDOR_ID_SILICOM_DENMARK, PCIE_DEVICE_ID_SILICOM_PAC_N5011),},
99 	{0,}
100 };
101 MODULE_DEVICE_TABLE(pci, cci_pcie_id_tbl);
102 
103 static int cci_init_drvdata(struct pci_dev *pcidev)
104 {
105 	struct cci_drvdata *drvdata;
106 
107 	drvdata = devm_kzalloc(&pcidev->dev, sizeof(*drvdata), GFP_KERNEL);
108 	if (!drvdata)
109 		return -ENOMEM;
110 
111 	pci_set_drvdata(pcidev, drvdata);
112 
113 	return 0;
114 }
115 
116 static void cci_remove_feature_devs(struct pci_dev *pcidev)
117 {
118 	struct cci_drvdata *drvdata = pci_get_drvdata(pcidev);
119 
120 	/* remove all children feature devices */
121 	dfl_fpga_feature_devs_remove(drvdata->cdev);
122 	cci_pci_free_irq(pcidev);
123 }
124 
125 static int *cci_pci_create_irq_table(struct pci_dev *pcidev, unsigned int nvec)
126 {
127 	unsigned int i;
128 	int *table;
129 
130 	table = kcalloc(nvec, sizeof(int), GFP_KERNEL);
131 	if (!table)
132 		return table;
133 
134 	for (i = 0; i < nvec; i++)
135 		table[i] = pci_irq_vector(pcidev, i);
136 
137 	return table;
138 }
139 
140 static int find_dfls_by_vsec(struct pci_dev *pcidev, struct dfl_fpga_enum_info *info)
141 {
142 	u32 bir, offset, vndr_hdr, dfl_cnt, dfl_res;
143 	int dfl_res_off, i, bars, voff = 0;
144 	resource_size_t start, len;
145 
146 	while ((voff = pci_find_next_ext_capability(pcidev, voff, PCI_EXT_CAP_ID_VNDR))) {
147 		vndr_hdr = 0;
148 		pci_read_config_dword(pcidev, voff + PCI_VNDR_HEADER, &vndr_hdr);
149 
150 		if (PCI_VNDR_HEADER_ID(vndr_hdr) == PCI_VSEC_ID_INTEL_DFLS &&
151 		    pcidev->vendor == PCI_VENDOR_ID_INTEL)
152 			break;
153 	}
154 
155 	if (!voff) {
156 		dev_dbg(&pcidev->dev, "%s no DFL VSEC found\n", __func__);
157 		return -ENODEV;
158 	}
159 
160 	dfl_cnt = 0;
161 	pci_read_config_dword(pcidev, voff + PCI_VNDR_DFLS_CNT, &dfl_cnt);
162 	if (dfl_cnt > PCI_STD_NUM_BARS) {
163 		dev_err(&pcidev->dev, "%s too many DFLs %d > %d\n",
164 			__func__, dfl_cnt, PCI_STD_NUM_BARS);
165 		return -EINVAL;
166 	}
167 
168 	dfl_res_off = voff + PCI_VNDR_DFLS_RES;
169 	if (dfl_res_off + (dfl_cnt * sizeof(u32)) > PCI_CFG_SPACE_EXP_SIZE) {
170 		dev_err(&pcidev->dev, "%s DFL VSEC too big for PCIe config space\n",
171 			__func__);
172 		return -EINVAL;
173 	}
174 
175 	for (i = 0, bars = 0; i < dfl_cnt; i++, dfl_res_off += sizeof(u32)) {
176 		dfl_res = GENMASK(31, 0);
177 		pci_read_config_dword(pcidev, dfl_res_off, &dfl_res);
178 
179 		bir = dfl_res & PCI_VNDR_DFLS_RES_BAR_MASK;
180 		if (bir >= PCI_STD_NUM_BARS) {
181 			dev_err(&pcidev->dev, "%s bad bir number %d\n",
182 				__func__, bir);
183 			return -EINVAL;
184 		}
185 
186 		if (bars & BIT(bir)) {
187 			dev_err(&pcidev->dev, "%s DFL for BAR %d already specified\n",
188 				__func__, bir);
189 			return -EINVAL;
190 		}
191 
192 		bars |= BIT(bir);
193 
194 		len = pci_resource_len(pcidev, bir);
195 		offset = dfl_res & PCI_VNDR_DFLS_RES_OFF_MASK;
196 		if (offset >= len) {
197 			dev_err(&pcidev->dev, "%s bad offset %u >= %pa\n",
198 				__func__, offset, &len);
199 			return -EINVAL;
200 		}
201 
202 		dev_dbg(&pcidev->dev, "%s BAR %d offset 0x%x\n", __func__, bir, offset);
203 
204 		len -= offset;
205 
206 		start = pci_resource_start(pcidev, bir) + offset;
207 
208 		dfl_fpga_enum_info_add_dfl(info, start, len);
209 	}
210 
211 	return 0;
212 }
213 
214 /* default method of finding dfls starting at offset 0 of bar 0 */
215 static int find_dfls_by_default(struct pci_dev *pcidev,
216 				struct dfl_fpga_enum_info *info)
217 {
218 	int port_num, bar, i, ret = 0;
219 	resource_size_t start, len;
220 	void __iomem *base;
221 	u32 offset;
222 	u64 v;
223 
224 	/* start to find Device Feature List from Bar 0 */
225 	base = cci_pci_ioremap_bar0(pcidev);
226 	if (!base)
227 		return -ENOMEM;
228 
229 	/*
230 	 * PF device has FME and Ports/AFUs, and VF device only has one
231 	 * Port/AFU. Check them and add related "Device Feature List" info
232 	 * for the next step enumeration.
233 	 */
234 	if (dfl_feature_is_fme(base)) {
235 		start = pci_resource_start(pcidev, 0);
236 		len = pci_resource_len(pcidev, 0);
237 
238 		dfl_fpga_enum_info_add_dfl(info, start, len);
239 
240 		/*
241 		 * find more Device Feature Lists (e.g. Ports) per information
242 		 * indicated by FME module.
243 		 */
244 		v = readq(base + FME_HDR_CAP);
245 		port_num = FIELD_GET(FME_CAP_NUM_PORTS, v);
246 
247 		WARN_ON(port_num > MAX_DFL_FPGA_PORT_NUM);
248 
249 		for (i = 0; i < port_num; i++) {
250 			v = readq(base + FME_HDR_PORT_OFST(i));
251 
252 			/* skip ports which are not implemented. */
253 			if (!(v & FME_PORT_OFST_IMP))
254 				continue;
255 
256 			/*
257 			 * add Port's Device Feature List information for next
258 			 * step enumeration.
259 			 */
260 			bar = FIELD_GET(FME_PORT_OFST_BAR_ID, v);
261 			offset = FIELD_GET(FME_PORT_OFST_DFH_OFST, v);
262 			start = pci_resource_start(pcidev, bar) + offset;
263 			len = pci_resource_len(pcidev, bar) - offset;
264 
265 			dfl_fpga_enum_info_add_dfl(info, start, len);
266 		}
267 	} else if (dfl_feature_is_port(base)) {
268 		start = pci_resource_start(pcidev, 0);
269 		len = pci_resource_len(pcidev, 0);
270 
271 		dfl_fpga_enum_info_add_dfl(info, start, len);
272 	} else {
273 		ret = -ENODEV;
274 	}
275 
276 	/* release I/O mappings for next step enumeration */
277 	pcim_iounmap_regions(pcidev, BIT(0));
278 
279 	return ret;
280 }
281 
282 /* enumerate feature devices under pci device */
283 static int cci_enumerate_feature_devs(struct pci_dev *pcidev)
284 {
285 	struct cci_drvdata *drvdata = pci_get_drvdata(pcidev);
286 	struct dfl_fpga_enum_info *info;
287 	struct dfl_fpga_cdev *cdev;
288 	int nvec, ret = 0;
289 	int *irq_table;
290 
291 	/* allocate enumeration info via pci_dev */
292 	info = dfl_fpga_enum_info_alloc(&pcidev->dev);
293 	if (!info)
294 		return -ENOMEM;
295 
296 	/* add irq info for enumeration if the device support irq */
297 	nvec = cci_pci_alloc_irq(pcidev);
298 	if (nvec < 0) {
299 		dev_err(&pcidev->dev, "Fail to alloc irq %d.\n", nvec);
300 		ret = nvec;
301 		goto enum_info_free_exit;
302 	} else if (nvec) {
303 		irq_table = cci_pci_create_irq_table(pcidev, nvec);
304 		if (!irq_table) {
305 			ret = -ENOMEM;
306 			goto irq_free_exit;
307 		}
308 
309 		ret = dfl_fpga_enum_info_add_irq(info, nvec, irq_table);
310 		kfree(irq_table);
311 		if (ret)
312 			goto irq_free_exit;
313 	}
314 
315 	ret = find_dfls_by_vsec(pcidev, info);
316 	if (ret == -ENODEV)
317 		ret = find_dfls_by_default(pcidev, info);
318 
319 	if (ret)
320 		goto irq_free_exit;
321 
322 	/* start enumeration with prepared enumeration information */
323 	cdev = dfl_fpga_feature_devs_enumerate(info);
324 	if (IS_ERR(cdev)) {
325 		dev_err(&pcidev->dev, "Enumeration failure\n");
326 		ret = PTR_ERR(cdev);
327 		goto irq_free_exit;
328 	}
329 
330 	drvdata->cdev = cdev;
331 
332 irq_free_exit:
333 	if (ret)
334 		cci_pci_free_irq(pcidev);
335 enum_info_free_exit:
336 	dfl_fpga_enum_info_free(info);
337 
338 	return ret;
339 }
340 
341 static
342 int cci_pci_probe(struct pci_dev *pcidev, const struct pci_device_id *pcidevid)
343 {
344 	int ret;
345 
346 	ret = pcim_enable_device(pcidev);
347 	if (ret < 0) {
348 		dev_err(&pcidev->dev, "Failed to enable device %d.\n", ret);
349 		return ret;
350 	}
351 
352 	ret = pci_enable_pcie_error_reporting(pcidev);
353 	if (ret && ret != -EINVAL)
354 		dev_info(&pcidev->dev, "PCIE AER unavailable %d.\n", ret);
355 
356 	pci_set_master(pcidev);
357 
358 	ret = dma_set_mask_and_coherent(&pcidev->dev, DMA_BIT_MASK(64));
359 	if (ret)
360 		ret = dma_set_mask_and_coherent(&pcidev->dev, DMA_BIT_MASK(32));
361 	if (ret) {
362 		dev_err(&pcidev->dev, "No suitable DMA support available.\n");
363 		goto disable_error_report_exit;
364 	}
365 
366 	ret = cci_init_drvdata(pcidev);
367 	if (ret) {
368 		dev_err(&pcidev->dev, "Fail to init drvdata %d.\n", ret);
369 		goto disable_error_report_exit;
370 	}
371 
372 	ret = cci_enumerate_feature_devs(pcidev);
373 	if (!ret)
374 		return ret;
375 
376 	dev_err(&pcidev->dev, "enumeration failure %d.\n", ret);
377 
378 disable_error_report_exit:
379 	pci_disable_pcie_error_reporting(pcidev);
380 	return ret;
381 }
382 
383 static int cci_pci_sriov_configure(struct pci_dev *pcidev, int num_vfs)
384 {
385 	struct cci_drvdata *drvdata = pci_get_drvdata(pcidev);
386 	struct dfl_fpga_cdev *cdev = drvdata->cdev;
387 
388 	if (!num_vfs) {
389 		/*
390 		 * disable SRIOV and then put released ports back to default
391 		 * PF access mode.
392 		 */
393 		pci_disable_sriov(pcidev);
394 
395 		dfl_fpga_cdev_config_ports_pf(cdev);
396 
397 	} else {
398 		int ret;
399 
400 		/*
401 		 * before enable SRIOV, put released ports into VF access mode
402 		 * first of all.
403 		 */
404 		ret = dfl_fpga_cdev_config_ports_vf(cdev, num_vfs);
405 		if (ret)
406 			return ret;
407 
408 		ret = pci_enable_sriov(pcidev, num_vfs);
409 		if (ret) {
410 			dfl_fpga_cdev_config_ports_pf(cdev);
411 			return ret;
412 		}
413 	}
414 
415 	return num_vfs;
416 }
417 
418 static void cci_pci_remove(struct pci_dev *pcidev)
419 {
420 	if (dev_is_pf(&pcidev->dev))
421 		cci_pci_sriov_configure(pcidev, 0);
422 
423 	cci_remove_feature_devs(pcidev);
424 	pci_disable_pcie_error_reporting(pcidev);
425 }
426 
427 static struct pci_driver cci_pci_driver = {
428 	.name = DRV_NAME,
429 	.id_table = cci_pcie_id_tbl,
430 	.probe = cci_pci_probe,
431 	.remove = cci_pci_remove,
432 	.sriov_configure = cci_pci_sriov_configure,
433 };
434 
435 module_pci_driver(cci_pci_driver);
436 
437 MODULE_DESCRIPTION("FPGA DFL PCIe Device Driver");
438 MODULE_AUTHOR("Intel Corporation");
439 MODULE_LICENSE("GPL v2");
440