xref: /openbmc/linux/drivers/fpga/dfl-pci.c (revision b21a5763)
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 /* VF Device */
78 #define PCIE_DEVICE_ID_VF_INT_5_X		0xBCBF
79 #define PCIE_DEVICE_ID_VF_INT_6_X		0xBCC1
80 #define PCIE_DEVICE_ID_VF_DSC_1_X		0x09C5
81 #define PCIE_DEVICE_ID_INTEL_PAC_D5005_VF	0x0B2C
82 
83 static struct pci_device_id cci_pcie_id_tbl[] = {
84 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCIE_DEVICE_ID_PF_INT_5_X),},
85 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCIE_DEVICE_ID_VF_INT_5_X),},
86 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCIE_DEVICE_ID_PF_INT_6_X),},
87 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCIE_DEVICE_ID_VF_INT_6_X),},
88 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCIE_DEVICE_ID_PF_DSC_1_X),},
89 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCIE_DEVICE_ID_VF_DSC_1_X),},
90 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCIE_DEVICE_ID_INTEL_PAC_N3000),},
91 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCIE_DEVICE_ID_INTEL_PAC_D5005),},
92 	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCIE_DEVICE_ID_INTEL_PAC_D5005_VF),},
93 	{0,}
94 };
95 MODULE_DEVICE_TABLE(pci, cci_pcie_id_tbl);
96 
97 static int cci_init_drvdata(struct pci_dev *pcidev)
98 {
99 	struct cci_drvdata *drvdata;
100 
101 	drvdata = devm_kzalloc(&pcidev->dev, sizeof(*drvdata), GFP_KERNEL);
102 	if (!drvdata)
103 		return -ENOMEM;
104 
105 	pci_set_drvdata(pcidev, drvdata);
106 
107 	return 0;
108 }
109 
110 static void cci_remove_feature_devs(struct pci_dev *pcidev)
111 {
112 	struct cci_drvdata *drvdata = pci_get_drvdata(pcidev);
113 
114 	/* remove all children feature devices */
115 	dfl_fpga_feature_devs_remove(drvdata->cdev);
116 	cci_pci_free_irq(pcidev);
117 }
118 
119 static int *cci_pci_create_irq_table(struct pci_dev *pcidev, unsigned int nvec)
120 {
121 	unsigned int i;
122 	int *table;
123 
124 	table = kcalloc(nvec, sizeof(int), GFP_KERNEL);
125 	if (!table)
126 		return table;
127 
128 	for (i = 0; i < nvec; i++)
129 		table[i] = pci_irq_vector(pcidev, i);
130 
131 	return table;
132 }
133 
134 static int find_dfls_by_vsec(struct pci_dev *pcidev, struct dfl_fpga_enum_info *info)
135 {
136 	u32 bir, offset, vndr_hdr, dfl_cnt, dfl_res;
137 	int dfl_res_off, i, bars, voff = 0;
138 	resource_size_t start, len;
139 
140 	while ((voff = pci_find_next_ext_capability(pcidev, voff, PCI_EXT_CAP_ID_VNDR))) {
141 		vndr_hdr = 0;
142 		pci_read_config_dword(pcidev, voff + PCI_VNDR_HEADER, &vndr_hdr);
143 
144 		if (PCI_VNDR_HEADER_ID(vndr_hdr) == PCI_VSEC_ID_INTEL_DFLS &&
145 		    pcidev->vendor == PCI_VENDOR_ID_INTEL)
146 			break;
147 	}
148 
149 	if (!voff) {
150 		dev_dbg(&pcidev->dev, "%s no DFL VSEC found\n", __func__);
151 		return -ENODEV;
152 	}
153 
154 	dfl_cnt = 0;
155 	pci_read_config_dword(pcidev, voff + PCI_VNDR_DFLS_CNT, &dfl_cnt);
156 	if (dfl_cnt > PCI_STD_NUM_BARS) {
157 		dev_err(&pcidev->dev, "%s too many DFLs %d > %d\n",
158 			__func__, dfl_cnt, PCI_STD_NUM_BARS);
159 		return -EINVAL;
160 	}
161 
162 	dfl_res_off = voff + PCI_VNDR_DFLS_RES;
163 	if (dfl_res_off + (dfl_cnt * sizeof(u32)) > PCI_CFG_SPACE_EXP_SIZE) {
164 		dev_err(&pcidev->dev, "%s DFL VSEC too big for PCIe config space\n",
165 			__func__);
166 		return -EINVAL;
167 	}
168 
169 	for (i = 0, bars = 0; i < dfl_cnt; i++, dfl_res_off += sizeof(u32)) {
170 		dfl_res = GENMASK(31, 0);
171 		pci_read_config_dword(pcidev, dfl_res_off, &dfl_res);
172 
173 		bir = dfl_res & PCI_VNDR_DFLS_RES_BAR_MASK;
174 		if (bir >= PCI_STD_NUM_BARS) {
175 			dev_err(&pcidev->dev, "%s bad bir number %d\n",
176 				__func__, bir);
177 			return -EINVAL;
178 		}
179 
180 		if (bars & BIT(bir)) {
181 			dev_err(&pcidev->dev, "%s DFL for BAR %d already specified\n",
182 				__func__, bir);
183 			return -EINVAL;
184 		}
185 
186 		bars |= BIT(bir);
187 
188 		len = pci_resource_len(pcidev, bir);
189 		offset = dfl_res & PCI_VNDR_DFLS_RES_OFF_MASK;
190 		if (offset >= len) {
191 			dev_err(&pcidev->dev, "%s bad offset %u >= %pa\n",
192 				__func__, offset, &len);
193 			return -EINVAL;
194 		}
195 
196 		dev_dbg(&pcidev->dev, "%s BAR %d offset 0x%x\n", __func__, bir, offset);
197 
198 		len -= offset;
199 
200 		start = pci_resource_start(pcidev, bir) + offset;
201 
202 		dfl_fpga_enum_info_add_dfl(info, start, len);
203 	}
204 
205 	return 0;
206 }
207 
208 /* default method of finding dfls starting at offset 0 of bar 0 */
209 static int find_dfls_by_default(struct pci_dev *pcidev,
210 				struct dfl_fpga_enum_info *info)
211 {
212 	int port_num, bar, i, ret = 0;
213 	resource_size_t start, len;
214 	void __iomem *base;
215 	u32 offset;
216 	u64 v;
217 
218 	/* start to find Device Feature List from Bar 0 */
219 	base = cci_pci_ioremap_bar0(pcidev);
220 	if (!base)
221 		return -ENOMEM;
222 
223 	/*
224 	 * PF device has FME and Ports/AFUs, and VF device only has one
225 	 * Port/AFU. Check them and add related "Device Feature List" info
226 	 * for the next step enumeration.
227 	 */
228 	if (dfl_feature_is_fme(base)) {
229 		start = pci_resource_start(pcidev, 0);
230 		len = pci_resource_len(pcidev, 0);
231 
232 		dfl_fpga_enum_info_add_dfl(info, start, len);
233 
234 		/*
235 		 * find more Device Feature Lists (e.g. Ports) per information
236 		 * indicated by FME module.
237 		 */
238 		v = readq(base + FME_HDR_CAP);
239 		port_num = FIELD_GET(FME_CAP_NUM_PORTS, v);
240 
241 		WARN_ON(port_num > MAX_DFL_FPGA_PORT_NUM);
242 
243 		for (i = 0; i < port_num; i++) {
244 			v = readq(base + FME_HDR_PORT_OFST(i));
245 
246 			/* skip ports which are not implemented. */
247 			if (!(v & FME_PORT_OFST_IMP))
248 				continue;
249 
250 			/*
251 			 * add Port's Device Feature List information for next
252 			 * step enumeration.
253 			 */
254 			bar = FIELD_GET(FME_PORT_OFST_BAR_ID, v);
255 			offset = FIELD_GET(FME_PORT_OFST_DFH_OFST, v);
256 			start = pci_resource_start(pcidev, bar) + offset;
257 			len = pci_resource_len(pcidev, bar) - offset;
258 
259 			dfl_fpga_enum_info_add_dfl(info, start, len);
260 		}
261 	} else if (dfl_feature_is_port(base)) {
262 		start = pci_resource_start(pcidev, 0);
263 		len = pci_resource_len(pcidev, 0);
264 
265 		dfl_fpga_enum_info_add_dfl(info, start, len);
266 	} else {
267 		ret = -ENODEV;
268 	}
269 
270 	/* release I/O mappings for next step enumeration */
271 	pcim_iounmap_regions(pcidev, BIT(0));
272 
273 	return ret;
274 }
275 
276 /* enumerate feature devices under pci device */
277 static int cci_enumerate_feature_devs(struct pci_dev *pcidev)
278 {
279 	struct cci_drvdata *drvdata = pci_get_drvdata(pcidev);
280 	struct dfl_fpga_enum_info *info;
281 	struct dfl_fpga_cdev *cdev;
282 	int nvec, ret = 0;
283 	int *irq_table;
284 
285 	/* allocate enumeration info via pci_dev */
286 	info = dfl_fpga_enum_info_alloc(&pcidev->dev);
287 	if (!info)
288 		return -ENOMEM;
289 
290 	/* add irq info for enumeration if the device support irq */
291 	nvec = cci_pci_alloc_irq(pcidev);
292 	if (nvec < 0) {
293 		dev_err(&pcidev->dev, "Fail to alloc irq %d.\n", nvec);
294 		ret = nvec;
295 		goto enum_info_free_exit;
296 	} else if (nvec) {
297 		irq_table = cci_pci_create_irq_table(pcidev, nvec);
298 		if (!irq_table) {
299 			ret = -ENOMEM;
300 			goto irq_free_exit;
301 		}
302 
303 		ret = dfl_fpga_enum_info_add_irq(info, nvec, irq_table);
304 		kfree(irq_table);
305 		if (ret)
306 			goto irq_free_exit;
307 	}
308 
309 	ret = find_dfls_by_vsec(pcidev, info);
310 	if (ret == -ENODEV)
311 		ret = find_dfls_by_default(pcidev, info);
312 
313 	if (ret)
314 		goto irq_free_exit;
315 
316 	/* start enumeration with prepared enumeration information */
317 	cdev = dfl_fpga_feature_devs_enumerate(info);
318 	if (IS_ERR(cdev)) {
319 		dev_err(&pcidev->dev, "Enumeration failure\n");
320 		ret = PTR_ERR(cdev);
321 		goto irq_free_exit;
322 	}
323 
324 	drvdata->cdev = cdev;
325 
326 irq_free_exit:
327 	if (ret)
328 		cci_pci_free_irq(pcidev);
329 enum_info_free_exit:
330 	dfl_fpga_enum_info_free(info);
331 
332 	return ret;
333 }
334 
335 static
336 int cci_pci_probe(struct pci_dev *pcidev, const struct pci_device_id *pcidevid)
337 {
338 	int ret;
339 
340 	ret = pcim_enable_device(pcidev);
341 	if (ret < 0) {
342 		dev_err(&pcidev->dev, "Failed to enable device %d.\n", ret);
343 		return ret;
344 	}
345 
346 	ret = pci_enable_pcie_error_reporting(pcidev);
347 	if (ret && ret != -EINVAL)
348 		dev_info(&pcidev->dev, "PCIE AER unavailable %d.\n", ret);
349 
350 	pci_set_master(pcidev);
351 
352 	if (!pci_set_dma_mask(pcidev, DMA_BIT_MASK(64))) {
353 		ret = pci_set_consistent_dma_mask(pcidev, DMA_BIT_MASK(64));
354 		if (ret)
355 			goto disable_error_report_exit;
356 	} else if (!pci_set_dma_mask(pcidev, DMA_BIT_MASK(32))) {
357 		ret = pci_set_consistent_dma_mask(pcidev, DMA_BIT_MASK(32));
358 		if (ret)
359 			goto disable_error_report_exit;
360 	} else {
361 		ret = -EIO;
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