xref: /linux/drivers/vdpa/ifcvf/ifcvf_base.c (revision daa2be74b1b2302004945b2a5e32424e177cc7da)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Intel IFC VF NIC driver for virtio dataplane offloading
4  *
5  * Copyright (C) 2020 Intel Corporation.
6  *
7  * Author: Zhu Lingshan <lingshan.zhu@intel.com>
8  *
9  */
10 
11 #include "ifcvf_base.h"
12 
13 u16 ifcvf_set_vq_vector(struct ifcvf_hw *hw, u16 qid, int vector)
14 {
15 	struct virtio_pci_common_cfg __iomem *cfg = hw->common_cfg;
16 
17 	vp_iowrite16(qid, &cfg->queue_select);
18 	vp_iowrite16(vector, &cfg->queue_msix_vector);
19 
20 	return vp_ioread16(&cfg->queue_msix_vector);
21 }
22 
23 u16 ifcvf_set_config_vector(struct ifcvf_hw *hw, int vector)
24 {
25 	struct virtio_pci_common_cfg __iomem *cfg = hw->common_cfg;
26 
27 	vp_iowrite16(vector,  &cfg->msix_config);
28 
29 	return vp_ioread16(&cfg->msix_config);
30 }
31 
32 static void __iomem *get_cap_addr(struct ifcvf_hw *hw,
33 				  struct virtio_pci_cap *cap)
34 {
35 	u32 length, offset;
36 	u8 bar;
37 
38 	length = le32_to_cpu(cap->length);
39 	offset = le32_to_cpu(cap->offset);
40 	bar = cap->bar;
41 
42 	if (bar >= IFCVF_PCI_MAX_RESOURCE) {
43 		IFCVF_DBG(hw->pdev,
44 			  "Invalid bar number %u to get capabilities\n", bar);
45 		return NULL;
46 	}
47 
48 	if (offset + length > pci_resource_len(hw->pdev, bar)) {
49 		IFCVF_DBG(hw->pdev,
50 			  "offset(%u) + len(%u) overflows bar%u's capability\n",
51 			  offset, length, bar);
52 		return NULL;
53 	}
54 
55 	return hw->base[bar] + offset;
56 }
57 
58 static int ifcvf_read_config_range(struct pci_dev *dev,
59 				   uint32_t *val, int size, int where)
60 {
61 	int ret, i;
62 
63 	for (i = 0; i < size; i += 4) {
64 		ret = pci_read_config_dword(dev, where + i, val + i / 4);
65 		if (ret < 0)
66 			return ret;
67 	}
68 
69 	return 0;
70 }
71 
72 u16 ifcvf_get_vq_size(struct ifcvf_hw *hw, u16 qid)
73 {
74 	u16 queue_size;
75 
76 	if (qid >= hw->nr_vring)
77 		return 0;
78 
79 	vp_iowrite16(qid, &hw->common_cfg->queue_select);
80 	queue_size = vp_ioread16(&hw->common_cfg->queue_size);
81 
82 	return queue_size;
83 }
84 
85 u16 ifcvf_get_max_vq_size(struct ifcvf_hw *hw)
86 {
87 	u16 queue_size, max_size, qid;
88 
89 	max_size = ifcvf_get_vq_size(hw, 0);
90 	for (qid = 1; qid < hw->nr_vring; qid++) {
91 		queue_size = ifcvf_get_vq_size(hw, qid);
92 		/* 0 means the queue is unavailable */
93 		if (!queue_size)
94 			continue;
95 
96 		max_size = max(queue_size, max_size);
97 	}
98 
99 	return max_size;
100 }
101 
102 int ifcvf_init_hw(struct ifcvf_hw *hw, struct pci_dev *pdev)
103 {
104 	struct virtio_pci_cap cap;
105 	u16 notify_off;
106 	int ret;
107 	u8 pos;
108 	u32 i;
109 
110 	ret = pci_read_config_byte(pdev, PCI_CAPABILITY_LIST, &pos);
111 	if (ret < 0) {
112 		IFCVF_ERR(pdev, "Failed to read PCI capability list\n");
113 		return -EIO;
114 	}
115 	hw->pdev = pdev;
116 
117 	while (pos) {
118 		ret = ifcvf_read_config_range(pdev, (u32 *)&cap,
119 					      sizeof(cap), pos);
120 		if (ret < 0) {
121 			IFCVF_ERR(pdev,
122 				  "Failed to get PCI capability at %x\n", pos);
123 			break;
124 		}
125 
126 		if (cap.cap_vndr != PCI_CAP_ID_VNDR)
127 			goto next;
128 
129 		switch (cap.cfg_type) {
130 		case VIRTIO_PCI_CAP_COMMON_CFG:
131 			hw->common_cfg = get_cap_addr(hw, &cap);
132 			IFCVF_DBG(pdev, "hw->common_cfg = %p\n",
133 				  hw->common_cfg);
134 			break;
135 		case VIRTIO_PCI_CAP_NOTIFY_CFG:
136 			pci_read_config_dword(pdev, pos + sizeof(cap),
137 					      &hw->notify_off_multiplier);
138 			hw->notify_bar = cap.bar;
139 			hw->notify_base = get_cap_addr(hw, &cap);
140 			hw->notify_base_pa = pci_resource_start(pdev, cap.bar) +
141 					le32_to_cpu(cap.offset);
142 			IFCVF_DBG(pdev, "hw->notify_base = %p\n",
143 				  hw->notify_base);
144 			break;
145 		case VIRTIO_PCI_CAP_ISR_CFG:
146 			hw->isr = get_cap_addr(hw, &cap);
147 			IFCVF_DBG(pdev, "hw->isr = %p\n", hw->isr);
148 			break;
149 		case VIRTIO_PCI_CAP_DEVICE_CFG:
150 			hw->dev_cfg = get_cap_addr(hw, &cap);
151 			hw->cap_dev_config_size = le32_to_cpu(cap.length);
152 			IFCVF_DBG(pdev, "hw->dev_cfg = %p\n", hw->dev_cfg);
153 			break;
154 		}
155 
156 next:
157 		pos = cap.cap_next;
158 	}
159 
160 	if (hw->common_cfg == NULL || hw->notify_base == NULL ||
161 	    hw->isr == NULL || hw->dev_cfg == NULL) {
162 		IFCVF_ERR(pdev, "Incomplete PCI capabilities\n");
163 		return -EIO;
164 	}
165 
166 	hw->nr_vring = vp_ioread16(&hw->common_cfg->num_queues);
167 	hw->vring = kzalloc(sizeof(struct vring_info) * hw->nr_vring, GFP_KERNEL);
168 	if (!hw->vring)
169 		return -ENOMEM;
170 
171 	for (i = 0; i < hw->nr_vring; i++) {
172 		vp_iowrite16(i, &hw->common_cfg->queue_select);
173 		notify_off = vp_ioread16(&hw->common_cfg->queue_notify_off);
174 		hw->vring[i].notify_addr = hw->notify_base +
175 			notify_off * hw->notify_off_multiplier;
176 		hw->vring[i].notify_pa = hw->notify_base_pa +
177 			notify_off * hw->notify_off_multiplier;
178 		hw->vring[i].irq = -EINVAL;
179 	}
180 
181 	hw->lm_cfg = hw->base[IFCVF_LM_BAR];
182 
183 	IFCVF_DBG(pdev,
184 		  "PCI capability mapping: common cfg: %p, notify base: %p\n, isr cfg: %p, device cfg: %p, multiplier: %u\n",
185 		  hw->common_cfg, hw->notify_base, hw->isr,
186 		  hw->dev_cfg, hw->notify_off_multiplier);
187 
188 	hw->vqs_reused_irq = -EINVAL;
189 	hw->config_irq = -EINVAL;
190 
191 	return 0;
192 }
193 
194 u8 ifcvf_get_status(struct ifcvf_hw *hw)
195 {
196 	return vp_ioread8(&hw->common_cfg->device_status);
197 }
198 
199 void ifcvf_set_status(struct ifcvf_hw *hw, u8 status)
200 {
201 	vp_iowrite8(status, &hw->common_cfg->device_status);
202 }
203 
204 void ifcvf_reset(struct ifcvf_hw *hw)
205 {
206 	ifcvf_set_status(hw, 0);
207 	while (ifcvf_get_status(hw))
208 		msleep(1);
209 }
210 
211 u64 ifcvf_get_hw_features(struct ifcvf_hw *hw)
212 {
213 	struct virtio_pci_common_cfg __iomem *cfg = hw->common_cfg;
214 	u32 features_lo, features_hi;
215 	u64 features;
216 
217 	vp_iowrite32(0, &cfg->device_feature_select);
218 	features_lo = vp_ioread32(&cfg->device_feature);
219 
220 	vp_iowrite32(1, &cfg->device_feature_select);
221 	features_hi = vp_ioread32(&cfg->device_feature);
222 
223 	features = ((u64)features_hi << 32) | features_lo;
224 
225 	return features;
226 }
227 
228 /* return provisioned vDPA dev features */
229 u64 ifcvf_get_dev_features(struct ifcvf_hw *hw)
230 {
231 	return hw->dev_features;
232 }
233 
234 u64 ifcvf_get_driver_features(struct ifcvf_hw *hw)
235 {
236 	struct virtio_pci_common_cfg __iomem *cfg = hw->common_cfg;
237 	u32 features_lo, features_hi;
238 	u64 features;
239 
240 	vp_iowrite32(0, &cfg->device_feature_select);
241 	features_lo = vp_ioread32(&cfg->guest_feature);
242 
243 	vp_iowrite32(1, &cfg->device_feature_select);
244 	features_hi = vp_ioread32(&cfg->guest_feature);
245 
246 	features = ((u64)features_hi << 32) | features_lo;
247 
248 	return features;
249 }
250 
251 int ifcvf_verify_min_features(struct ifcvf_hw *hw, u64 features)
252 {
253 	if (!(features & BIT_ULL(VIRTIO_F_ACCESS_PLATFORM)) && features) {
254 		IFCVF_ERR(hw->pdev, "VIRTIO_F_ACCESS_PLATFORM is not negotiated\n");
255 		return -EINVAL;
256 	}
257 
258 	return 0;
259 }
260 
261 u32 ifcvf_get_config_size(struct ifcvf_hw *hw)
262 {
263 	u32 net_config_size = sizeof(struct virtio_net_config);
264 	u32 blk_config_size = sizeof(struct virtio_blk_config);
265 	u32 cap_size = hw->cap_dev_config_size;
266 	u32 config_size;
267 
268 	/* If the onboard device config space size is greater than
269 	 * the size of struct virtio_net/blk_config, only the spec
270 	 * implementing contents size is returned, this is very
271 	 * unlikely, defensive programming.
272 	 */
273 	switch (hw->dev_type) {
274 	case VIRTIO_ID_NET:
275 		config_size = min(cap_size, net_config_size);
276 		break;
277 	case VIRTIO_ID_BLOCK:
278 		config_size = min(cap_size, blk_config_size);
279 		break;
280 	default:
281 		config_size = 0;
282 		IFCVF_ERR(hw->pdev, "VIRTIO ID %u not supported\n", hw->dev_type);
283 	}
284 
285 	return config_size;
286 }
287 
288 void ifcvf_read_dev_config(struct ifcvf_hw *hw, u64 offset,
289 			   void *dst, int length)
290 {
291 	u8 old_gen, new_gen, *p;
292 	int i;
293 
294 	WARN_ON(offset + length > hw->config_size);
295 	do {
296 		old_gen = vp_ioread8(&hw->common_cfg->config_generation);
297 		p = dst;
298 		for (i = 0; i < length; i++)
299 			*p++ = vp_ioread8(hw->dev_cfg + offset + i);
300 
301 		new_gen = vp_ioread8(&hw->common_cfg->config_generation);
302 	} while (old_gen != new_gen);
303 }
304 
305 void ifcvf_write_dev_config(struct ifcvf_hw *hw, u64 offset,
306 			    const void *src, int length)
307 {
308 	const u8 *p;
309 	int i;
310 
311 	p = src;
312 	WARN_ON(offset + length > hw->config_size);
313 	for (i = 0; i < length; i++)
314 		vp_iowrite8(*p++, hw->dev_cfg + offset + i);
315 }
316 
317 void ifcvf_set_driver_features(struct ifcvf_hw *hw, u64 features)
318 {
319 	struct virtio_pci_common_cfg __iomem *cfg = hw->common_cfg;
320 
321 	vp_iowrite32(0, &cfg->guest_feature_select);
322 	vp_iowrite32((u32)features, &cfg->guest_feature);
323 
324 	vp_iowrite32(1, &cfg->guest_feature_select);
325 	vp_iowrite32(features >> 32, &cfg->guest_feature);
326 }
327 
328 u16 ifcvf_get_vq_state(struct ifcvf_hw *hw, u16 qid)
329 {
330 	struct ifcvf_lm_cfg  __iomem *lm_cfg = hw->lm_cfg;
331 	u16 last_avail_idx;
332 
333 	last_avail_idx = vp_ioread16(&lm_cfg->vq_state_region + qid * 2);
334 
335 	return last_avail_idx;
336 }
337 
338 int ifcvf_set_vq_state(struct ifcvf_hw *hw, u16 qid, u16 num)
339 {
340 	struct ifcvf_lm_cfg  __iomem *lm_cfg = hw->lm_cfg;
341 
342 	vp_iowrite16(num, &lm_cfg->vq_state_region + qid * 2);
343 
344 	return 0;
345 }
346 
347 void ifcvf_set_vq_num(struct ifcvf_hw *hw, u16 qid, u32 num)
348 {
349 	struct virtio_pci_common_cfg __iomem *cfg = hw->common_cfg;
350 
351 	vp_iowrite16(qid, &cfg->queue_select);
352 	vp_iowrite16(num, &cfg->queue_size);
353 }
354 
355 int ifcvf_set_vq_address(struct ifcvf_hw *hw, u16 qid, u64 desc_area,
356 			 u64 driver_area, u64 device_area)
357 {
358 	struct virtio_pci_common_cfg __iomem *cfg = hw->common_cfg;
359 
360 	vp_iowrite16(qid, &cfg->queue_select);
361 	vp_iowrite64_twopart(desc_area, &cfg->queue_desc_lo,
362 			     &cfg->queue_desc_hi);
363 	vp_iowrite64_twopart(driver_area, &cfg->queue_avail_lo,
364 			     &cfg->queue_avail_hi);
365 	vp_iowrite64_twopart(device_area, &cfg->queue_used_lo,
366 			     &cfg->queue_used_hi);
367 
368 	return 0;
369 }
370 
371 bool ifcvf_get_vq_ready(struct ifcvf_hw *hw, u16 qid)
372 {
373 	struct virtio_pci_common_cfg __iomem *cfg = hw->common_cfg;
374 	u16 queue_enable;
375 
376 	vp_iowrite16(qid, &cfg->queue_select);
377 	queue_enable = vp_ioread16(&cfg->queue_enable);
378 
379 	return (bool)queue_enable;
380 }
381 
382 void ifcvf_set_vq_ready(struct ifcvf_hw *hw, u16 qid, bool ready)
383 {
384 	struct virtio_pci_common_cfg __iomem *cfg = hw->common_cfg;
385 
386 	vp_iowrite16(qid, &cfg->queue_select);
387 	vp_iowrite16(ready, &cfg->queue_enable);
388 }
389 
390 static void ifcvf_reset_vring(struct ifcvf_hw *hw)
391 {
392 	u16 qid;
393 
394 	for (qid = 0; qid < hw->nr_vring; qid++) {
395 		hw->vring[qid].cb.callback = NULL;
396 		hw->vring[qid].cb.private = NULL;
397 		ifcvf_set_vq_vector(hw, qid, VIRTIO_MSI_NO_VECTOR);
398 	}
399 }
400 
401 static void ifcvf_reset_config_handler(struct ifcvf_hw *hw)
402 {
403 	hw->config_cb.callback = NULL;
404 	hw->config_cb.private = NULL;
405 	ifcvf_set_config_vector(hw, VIRTIO_MSI_NO_VECTOR);
406 }
407 
408 static void ifcvf_synchronize_irq(struct ifcvf_hw *hw)
409 {
410 	u32 nvectors = hw->num_msix_vectors;
411 	struct pci_dev *pdev = hw->pdev;
412 	int i, irq;
413 
414 	for (i = 0; i < nvectors; i++) {
415 		irq = pci_irq_vector(pdev, i);
416 		if (irq >= 0)
417 			synchronize_irq(irq);
418 	}
419 }
420 
421 void ifcvf_stop(struct ifcvf_hw *hw)
422 {
423 	ifcvf_synchronize_irq(hw);
424 	ifcvf_reset_vring(hw);
425 	ifcvf_reset_config_handler(hw);
426 }
427 
428 void ifcvf_notify_queue(struct ifcvf_hw *hw, u16 qid)
429 {
430 	vp_iowrite16(qid, hw->vring[qid].notify_addr);
431 }
432