xref: /openbmc/linux/drivers/vdpa/ifcvf/ifcvf_base.c (revision 950ac86c)
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 static u16 ifcvf_get_vq_size(struct ifcvf_hw *hw, u16 qid)
73 {
74 	u16 queue_size;
75 
76 	vp_iowrite16(qid, &hw->common_cfg->queue_select);
77 	queue_size = vp_ioread16(&hw->common_cfg->queue_size);
78 
79 	return queue_size;
80 }
81 
82 /* This function returns the max allowed safe size for
83  * all virtqueues. It is the minimal size that can be
84  * suppprted by all virtqueues.
85  */
86 u16 ifcvf_get_max_vq_size(struct ifcvf_hw *hw)
87 {
88 	u16 queue_size, max_size, qid;
89 
90 	max_size = ifcvf_get_vq_size(hw, 0);
91 	for (qid = 1; qid < hw->nr_vring; qid++) {
92 		queue_size = ifcvf_get_vq_size(hw, qid);
93 		/* 0 means the queue is unavailable */
94 		if (!queue_size)
95 			continue;
96 
97 		max_size = min(queue_size, max_size);
98 	}
99 
100 	return max_size;
101 }
102 
103 int ifcvf_init_hw(struct ifcvf_hw *hw, struct pci_dev *pdev)
104 {
105 	struct virtio_pci_cap cap;
106 	u16 notify_off;
107 	int ret;
108 	u8 pos;
109 	u32 i;
110 
111 	ret = pci_read_config_byte(pdev, PCI_CAPABILITY_LIST, &pos);
112 	if (ret) {
113 		IFCVF_ERR(pdev, "Failed to read PCI capability list\n");
114 		return -EIO;
115 	}
116 	hw->pdev = pdev;
117 
118 	while (pos) {
119 		ret = ifcvf_read_config_range(pdev, (u32 *)&cap,
120 					      sizeof(cap), pos);
121 		if (ret < 0) {
122 			IFCVF_ERR(pdev,
123 				  "Failed to get PCI capability at %x\n", pos);
124 			break;
125 		}
126 
127 		if (cap.cap_vndr != PCI_CAP_ID_VNDR)
128 			goto next;
129 
130 		switch (cap.cfg_type) {
131 		case VIRTIO_PCI_CAP_COMMON_CFG:
132 			hw->common_cfg = get_cap_addr(hw, &cap);
133 			IFCVF_DBG(pdev, "hw->common_cfg = %p\n",
134 				  hw->common_cfg);
135 			break;
136 		case VIRTIO_PCI_CAP_NOTIFY_CFG:
137 			pci_read_config_dword(pdev, pos + sizeof(cap),
138 					      &hw->notify_off_multiplier);
139 			hw->notify_bar = cap.bar;
140 			hw->notify_base = get_cap_addr(hw, &cap);
141 			hw->notify_base_pa = pci_resource_start(pdev, cap.bar) +
142 					le32_to_cpu(cap.offset);
143 			IFCVF_DBG(pdev, "hw->notify_base = %p\n",
144 				  hw->notify_base);
145 			break;
146 		case VIRTIO_PCI_CAP_ISR_CFG:
147 			hw->isr = get_cap_addr(hw, &cap);
148 			IFCVF_DBG(pdev, "hw->isr = %p\n", hw->isr);
149 			break;
150 		case VIRTIO_PCI_CAP_DEVICE_CFG:
151 			hw->dev_cfg = get_cap_addr(hw, &cap);
152 			hw->cap_dev_config_size = le32_to_cpu(cap.length);
153 			IFCVF_DBG(pdev, "hw->dev_cfg = %p\n", hw->dev_cfg);
154 			break;
155 		}
156 
157 next:
158 		pos = cap.cap_next;
159 	}
160 
161 	if (hw->common_cfg == NULL || hw->notify_base == NULL ||
162 	    hw->isr == NULL || hw->dev_cfg == NULL) {
163 		IFCVF_ERR(pdev, "Incomplete PCI capabilities\n");
164 		return -EIO;
165 	}
166 
167 	hw->nr_vring = vp_ioread16(&hw->common_cfg->num_queues);
168 	hw->vring = kzalloc(sizeof(struct vring_info) * hw->nr_vring, GFP_KERNEL);
169 	if (!hw->vring)
170 		return -ENOMEM;
171 
172 	for (i = 0; i < hw->nr_vring; i++) {
173 		vp_iowrite16(i, &hw->common_cfg->queue_select);
174 		notify_off = vp_ioread16(&hw->common_cfg->queue_notify_off);
175 		hw->vring[i].notify_addr = hw->notify_base +
176 			notify_off * hw->notify_off_multiplier;
177 		hw->vring[i].notify_pa = hw->notify_base_pa +
178 			notify_off * hw->notify_off_multiplier;
179 		hw->vring[i].irq = -EINVAL;
180 	}
181 
182 	hw->lm_cfg = hw->base[IFCVF_LM_BAR];
183 
184 	IFCVF_DBG(pdev,
185 		  "PCI capability mapping: common cfg: %p, notify base: %p\n, isr cfg: %p, device cfg: %p, multiplier: %u\n",
186 		  hw->common_cfg, hw->notify_base, hw->isr,
187 		  hw->dev_cfg, hw->notify_off_multiplier);
188 
189 	hw->vqs_reused_irq = -EINVAL;
190 	hw->config_irq = -EINVAL;
191 
192 	return 0;
193 }
194 
195 u8 ifcvf_get_status(struct ifcvf_hw *hw)
196 {
197 	return vp_ioread8(&hw->common_cfg->device_status);
198 }
199 
200 void ifcvf_set_status(struct ifcvf_hw *hw, u8 status)
201 {
202 	vp_iowrite8(status, &hw->common_cfg->device_status);
203 }
204 
205 void ifcvf_reset(struct ifcvf_hw *hw)
206 {
207 	ifcvf_set_status(hw, 0);
208 	while (ifcvf_get_status(hw))
209 		msleep(1);
210 }
211 
212 u64 ifcvf_get_hw_features(struct ifcvf_hw *hw)
213 {
214 	struct virtio_pci_common_cfg __iomem *cfg = hw->common_cfg;
215 	u32 features_lo, features_hi;
216 	u64 features;
217 
218 	vp_iowrite32(0, &cfg->device_feature_select);
219 	features_lo = vp_ioread32(&cfg->device_feature);
220 
221 	vp_iowrite32(1, &cfg->device_feature_select);
222 	features_hi = vp_ioread32(&cfg->device_feature);
223 
224 	features = ((u64)features_hi << 32) | features_lo;
225 
226 	return features;
227 }
228 
229 /* return provisioned vDPA dev features */
230 u64 ifcvf_get_dev_features(struct ifcvf_hw *hw)
231 {
232 	return hw->dev_features;
233 }
234 
235 u64 ifcvf_get_driver_features(struct ifcvf_hw *hw)
236 {
237 	struct virtio_pci_common_cfg __iomem *cfg = hw->common_cfg;
238 	u32 features_lo, features_hi;
239 	u64 features;
240 
241 	vp_iowrite32(0, &cfg->device_feature_select);
242 	features_lo = vp_ioread32(&cfg->guest_feature);
243 
244 	vp_iowrite32(1, &cfg->device_feature_select);
245 	features_hi = vp_ioread32(&cfg->guest_feature);
246 
247 	features = ((u64)features_hi << 32) | features_lo;
248 
249 	return features;
250 }
251 
252 int ifcvf_verify_min_features(struct ifcvf_hw *hw, u64 features)
253 {
254 	if (!(features & BIT_ULL(VIRTIO_F_ACCESS_PLATFORM)) && features) {
255 		IFCVF_ERR(hw->pdev, "VIRTIO_F_ACCESS_PLATFORM is not negotiated\n");
256 		return -EINVAL;
257 	}
258 
259 	return 0;
260 }
261 
262 u32 ifcvf_get_config_size(struct ifcvf_hw *hw)
263 {
264 	u32 net_config_size = sizeof(struct virtio_net_config);
265 	u32 blk_config_size = sizeof(struct virtio_blk_config);
266 	u32 cap_size = hw->cap_dev_config_size;
267 	u32 config_size;
268 
269 	/* If the onboard device config space size is greater than
270 	 * the size of struct virtio_net/blk_config, only the spec
271 	 * implementing contents size is returned, this is very
272 	 * unlikely, defensive programming.
273 	 */
274 	switch (hw->dev_type) {
275 	case VIRTIO_ID_NET:
276 		config_size = min(cap_size, net_config_size);
277 		break;
278 	case VIRTIO_ID_BLOCK:
279 		config_size = min(cap_size, blk_config_size);
280 		break;
281 	default:
282 		config_size = 0;
283 		IFCVF_ERR(hw->pdev, "VIRTIO ID %u not supported\n", hw->dev_type);
284 	}
285 
286 	return config_size;
287 }
288 
289 void ifcvf_read_dev_config(struct ifcvf_hw *hw, u64 offset,
290 			   void *dst, int length)
291 {
292 	u8 old_gen, new_gen, *p;
293 	int i;
294 
295 	WARN_ON(offset + length > hw->config_size);
296 	do {
297 		old_gen = vp_ioread8(&hw->common_cfg->config_generation);
298 		p = dst;
299 		for (i = 0; i < length; i++)
300 			*p++ = vp_ioread8(hw->dev_cfg + offset + i);
301 
302 		new_gen = vp_ioread8(&hw->common_cfg->config_generation);
303 	} while (old_gen != new_gen);
304 }
305 
306 void ifcvf_write_dev_config(struct ifcvf_hw *hw, u64 offset,
307 			    const void *src, int length)
308 {
309 	const u8 *p;
310 	int i;
311 
312 	p = src;
313 	WARN_ON(offset + length > hw->config_size);
314 	for (i = 0; i < length; i++)
315 		vp_iowrite8(*p++, hw->dev_cfg + offset + i);
316 }
317 
318 void ifcvf_set_driver_features(struct ifcvf_hw *hw, u64 features)
319 {
320 	struct virtio_pci_common_cfg __iomem *cfg = hw->common_cfg;
321 
322 	vp_iowrite32(0, &cfg->guest_feature_select);
323 	vp_iowrite32((u32)features, &cfg->guest_feature);
324 
325 	vp_iowrite32(1, &cfg->guest_feature_select);
326 	vp_iowrite32(features >> 32, &cfg->guest_feature);
327 }
328 
329 u16 ifcvf_get_vq_state(struct ifcvf_hw *hw, u16 qid)
330 {
331 	struct ifcvf_lm_cfg  __iomem *lm_cfg = hw->lm_cfg;
332 	u16 last_avail_idx;
333 
334 	last_avail_idx = vp_ioread16(&lm_cfg->vq_state_region + qid * 2);
335 
336 	return last_avail_idx;
337 }
338 
339 int ifcvf_set_vq_state(struct ifcvf_hw *hw, u16 qid, u16 num)
340 {
341 	struct ifcvf_lm_cfg  __iomem *lm_cfg = hw->lm_cfg;
342 
343 	vp_iowrite16(num, &lm_cfg->vq_state_region + qid * 2);
344 
345 	return 0;
346 }
347 
348 void ifcvf_set_vq_num(struct ifcvf_hw *hw, u16 qid, u32 num)
349 {
350 	struct virtio_pci_common_cfg __iomem *cfg = hw->common_cfg;
351 
352 	vp_iowrite16(qid, &cfg->queue_select);
353 	vp_iowrite16(num, &cfg->queue_size);
354 }
355 
356 int ifcvf_set_vq_address(struct ifcvf_hw *hw, u16 qid, u64 desc_area,
357 			 u64 driver_area, u64 device_area)
358 {
359 	struct virtio_pci_common_cfg __iomem *cfg = hw->common_cfg;
360 
361 	vp_iowrite16(qid, &cfg->queue_select);
362 	vp_iowrite64_twopart(desc_area, &cfg->queue_desc_lo,
363 			     &cfg->queue_desc_hi);
364 	vp_iowrite64_twopart(driver_area, &cfg->queue_avail_lo,
365 			     &cfg->queue_avail_hi);
366 	vp_iowrite64_twopart(device_area, &cfg->queue_used_lo,
367 			     &cfg->queue_used_hi);
368 
369 	return 0;
370 }
371 
372 bool ifcvf_get_vq_ready(struct ifcvf_hw *hw, u16 qid)
373 {
374 	struct virtio_pci_common_cfg __iomem *cfg = hw->common_cfg;
375 	u16 queue_enable;
376 
377 	vp_iowrite16(qid, &cfg->queue_select);
378 	queue_enable = vp_ioread16(&cfg->queue_enable);
379 
380 	return (bool)queue_enable;
381 }
382 
383 void ifcvf_set_vq_ready(struct ifcvf_hw *hw, u16 qid, bool ready)
384 {
385 	struct virtio_pci_common_cfg __iomem *cfg = hw->common_cfg;
386 
387 	vp_iowrite16(qid, &cfg->queue_select);
388 	vp_iowrite16(ready, &cfg->queue_enable);
389 }
390 
391 static void ifcvf_reset_vring(struct ifcvf_hw *hw)
392 {
393 	u16 qid;
394 
395 	for (qid = 0; qid < hw->nr_vring; qid++) {
396 		hw->vring[qid].cb.callback = NULL;
397 		hw->vring[qid].cb.private = NULL;
398 		ifcvf_set_vq_vector(hw, qid, VIRTIO_MSI_NO_VECTOR);
399 	}
400 }
401 
402 static void ifcvf_reset_config_handler(struct ifcvf_hw *hw)
403 {
404 	hw->config_cb.callback = NULL;
405 	hw->config_cb.private = NULL;
406 	ifcvf_set_config_vector(hw, VIRTIO_MSI_NO_VECTOR);
407 }
408 
409 static void ifcvf_synchronize_irq(struct ifcvf_hw *hw)
410 {
411 	u32 nvectors = hw->num_msix_vectors;
412 	struct pci_dev *pdev = hw->pdev;
413 	int i, irq;
414 
415 	for (i = 0; i < nvectors; i++) {
416 		irq = pci_irq_vector(pdev, i);
417 		if (irq >= 0)
418 			synchronize_irq(irq);
419 	}
420 }
421 
422 void ifcvf_stop(struct ifcvf_hw *hw)
423 {
424 	ifcvf_synchronize_irq(hw);
425 	ifcvf_reset_vring(hw);
426 	ifcvf_reset_config_handler(hw);
427 }
428 
429 void ifcvf_notify_queue(struct ifcvf_hw *hw, u16 qid)
430 {
431 	vp_iowrite16(qid, hw->vring[qid].notify_addr);
432 }
433