xref: /linux/drivers/vdpa/ifcvf/ifcvf_base.c (revision 0e9ab8e4d44ae9d9aaf213bfd2c90bbe7289337b)
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 int ifcvf_init_hw(struct ifcvf_hw *hw, struct pci_dev *pdev)
73 {
74 	struct virtio_pci_cap cap;
75 	u16 notify_off;
76 	int ret;
77 	u8 pos;
78 	u32 i;
79 
80 	ret = pci_read_config_byte(pdev, PCI_CAPABILITY_LIST, &pos);
81 	if (ret < 0) {
82 		IFCVF_ERR(pdev, "Failed to read PCI capability list\n");
83 		return -EIO;
84 	}
85 	hw->pdev = pdev;
86 
87 	while (pos) {
88 		ret = ifcvf_read_config_range(pdev, (u32 *)&cap,
89 					      sizeof(cap), pos);
90 		if (ret < 0) {
91 			IFCVF_ERR(pdev,
92 				  "Failed to get PCI capability at %x\n", pos);
93 			break;
94 		}
95 
96 		if (cap.cap_vndr != PCI_CAP_ID_VNDR)
97 			goto next;
98 
99 		switch (cap.cfg_type) {
100 		case VIRTIO_PCI_CAP_COMMON_CFG:
101 			hw->common_cfg = get_cap_addr(hw, &cap);
102 			IFCVF_DBG(pdev, "hw->common_cfg = %p\n",
103 				  hw->common_cfg);
104 			break;
105 		case VIRTIO_PCI_CAP_NOTIFY_CFG:
106 			pci_read_config_dword(pdev, pos + sizeof(cap),
107 					      &hw->notify_off_multiplier);
108 			hw->notify_bar = cap.bar;
109 			hw->notify_base = get_cap_addr(hw, &cap);
110 			hw->notify_base_pa = pci_resource_start(pdev, cap.bar) +
111 					le32_to_cpu(cap.offset);
112 			IFCVF_DBG(pdev, "hw->notify_base = %p\n",
113 				  hw->notify_base);
114 			break;
115 		case VIRTIO_PCI_CAP_ISR_CFG:
116 			hw->isr = get_cap_addr(hw, &cap);
117 			IFCVF_DBG(pdev, "hw->isr = %p\n", hw->isr);
118 			break;
119 		case VIRTIO_PCI_CAP_DEVICE_CFG:
120 			hw->dev_cfg = get_cap_addr(hw, &cap);
121 			hw->cap_dev_config_size = le32_to_cpu(cap.length);
122 			IFCVF_DBG(pdev, "hw->dev_cfg = %p\n", hw->dev_cfg);
123 			break;
124 		}
125 
126 next:
127 		pos = cap.cap_next;
128 	}
129 
130 	if (hw->common_cfg == NULL || hw->notify_base == NULL ||
131 	    hw->isr == NULL || hw->dev_cfg == NULL) {
132 		IFCVF_ERR(pdev, "Incomplete PCI capabilities\n");
133 		return -EIO;
134 	}
135 
136 	hw->nr_vring = vp_ioread16(&hw->common_cfg->num_queues);
137 
138 	for (i = 0; i < hw->nr_vring; i++) {
139 		vp_iowrite16(i, &hw->common_cfg->queue_select);
140 		notify_off = vp_ioread16(&hw->common_cfg->queue_notify_off);
141 		hw->vring[i].notify_addr = hw->notify_base +
142 			notify_off * hw->notify_off_multiplier;
143 		hw->vring[i].notify_pa = hw->notify_base_pa +
144 			notify_off * hw->notify_off_multiplier;
145 		hw->vring[i].irq = -EINVAL;
146 	}
147 
148 	hw->lm_cfg = hw->base[IFCVF_LM_BAR];
149 
150 	IFCVF_DBG(pdev,
151 		  "PCI capability mapping: common cfg: %p, notify base: %p\n, isr cfg: %p, device cfg: %p, multiplier: %u\n",
152 		  hw->common_cfg, hw->notify_base, hw->isr,
153 		  hw->dev_cfg, hw->notify_off_multiplier);
154 
155 	hw->vqs_reused_irq = -EINVAL;
156 	hw->config_irq = -EINVAL;
157 
158 	return 0;
159 }
160 
161 u8 ifcvf_get_status(struct ifcvf_hw *hw)
162 {
163 	return vp_ioread8(&hw->common_cfg->device_status);
164 }
165 
166 void ifcvf_set_status(struct ifcvf_hw *hw, u8 status)
167 {
168 	vp_iowrite8(status, &hw->common_cfg->device_status);
169 }
170 
171 void ifcvf_reset(struct ifcvf_hw *hw)
172 {
173 	hw->config_cb.callback = NULL;
174 	hw->config_cb.private = NULL;
175 
176 	ifcvf_set_status(hw, 0);
177 	/* flush set_status, make sure VF is stopped, reset */
178 	ifcvf_get_status(hw);
179 }
180 
181 static void ifcvf_add_status(struct ifcvf_hw *hw, u8 status)
182 {
183 	if (status != 0)
184 		status |= ifcvf_get_status(hw);
185 
186 	ifcvf_set_status(hw, status);
187 	ifcvf_get_status(hw);
188 }
189 
190 u64 ifcvf_get_hw_features(struct ifcvf_hw *hw)
191 {
192 	struct virtio_pci_common_cfg __iomem *cfg = hw->common_cfg;
193 	u32 features_lo, features_hi;
194 	u64 features;
195 
196 	vp_iowrite32(0, &cfg->device_feature_select);
197 	features_lo = vp_ioread32(&cfg->device_feature);
198 
199 	vp_iowrite32(1, &cfg->device_feature_select);
200 	features_hi = vp_ioread32(&cfg->device_feature);
201 
202 	features = ((u64)features_hi << 32) | features_lo;
203 
204 	return features;
205 }
206 
207 u64 ifcvf_get_features(struct ifcvf_hw *hw)
208 {
209 	return hw->dev_features;
210 }
211 
212 int ifcvf_verify_min_features(struct ifcvf_hw *hw, u64 features)
213 {
214 	if (!(features & BIT_ULL(VIRTIO_F_ACCESS_PLATFORM)) && features) {
215 		IFCVF_ERR(hw->pdev, "VIRTIO_F_ACCESS_PLATFORM is not negotiated\n");
216 		return -EINVAL;
217 	}
218 
219 	return 0;
220 }
221 
222 u32 ifcvf_get_config_size(struct ifcvf_hw *hw)
223 {
224 	u32 net_config_size = sizeof(struct virtio_net_config);
225 	u32 blk_config_size = sizeof(struct virtio_blk_config);
226 	u32 cap_size = hw->cap_dev_config_size;
227 	u32 config_size;
228 
229 	/* If the onboard device config space size is greater than
230 	 * the size of struct virtio_net/blk_config, only the spec
231 	 * implementing contents size is returned, this is very
232 	 * unlikely, defensive programming.
233 	 */
234 	switch (hw->dev_type) {
235 	case VIRTIO_ID_NET:
236 		config_size = min(cap_size, net_config_size);
237 		break;
238 	case VIRTIO_ID_BLOCK:
239 		config_size = min(cap_size, blk_config_size);
240 		break;
241 	default:
242 		config_size = 0;
243 		IFCVF_ERR(hw->pdev, "VIRTIO ID %u not supported\n", hw->dev_type);
244 	}
245 
246 	return config_size;
247 }
248 
249 void ifcvf_read_dev_config(struct ifcvf_hw *hw, u64 offset,
250 			   void *dst, int length)
251 {
252 	u8 old_gen, new_gen, *p;
253 	int i;
254 
255 	WARN_ON(offset + length > hw->config_size);
256 	do {
257 		old_gen = vp_ioread8(&hw->common_cfg->config_generation);
258 		p = dst;
259 		for (i = 0; i < length; i++)
260 			*p++ = vp_ioread8(hw->dev_cfg + offset + i);
261 
262 		new_gen = vp_ioread8(&hw->common_cfg->config_generation);
263 	} while (old_gen != new_gen);
264 }
265 
266 void ifcvf_write_dev_config(struct ifcvf_hw *hw, u64 offset,
267 			    const void *src, int length)
268 {
269 	const u8 *p;
270 	int i;
271 
272 	p = src;
273 	WARN_ON(offset + length > hw->config_size);
274 	for (i = 0; i < length; i++)
275 		vp_iowrite8(*p++, hw->dev_cfg + offset + i);
276 }
277 
278 static void ifcvf_set_features(struct ifcvf_hw *hw, u64 features)
279 {
280 	struct virtio_pci_common_cfg __iomem *cfg = hw->common_cfg;
281 
282 	vp_iowrite32(0, &cfg->guest_feature_select);
283 	vp_iowrite32((u32)features, &cfg->guest_feature);
284 
285 	vp_iowrite32(1, &cfg->guest_feature_select);
286 	vp_iowrite32(features >> 32, &cfg->guest_feature);
287 }
288 
289 static int ifcvf_config_features(struct ifcvf_hw *hw)
290 {
291 	ifcvf_set_features(hw, hw->req_features);
292 	ifcvf_add_status(hw, VIRTIO_CONFIG_S_FEATURES_OK);
293 
294 	if (!(ifcvf_get_status(hw) & VIRTIO_CONFIG_S_FEATURES_OK)) {
295 		IFCVF_ERR(hw->pdev, "Failed to set FEATURES_OK status\n");
296 		return -EIO;
297 	}
298 
299 	return 0;
300 }
301 
302 u16 ifcvf_get_vq_state(struct ifcvf_hw *hw, u16 qid)
303 {
304 	struct ifcvf_lm_cfg __iomem *ifcvf_lm;
305 	void __iomem *avail_idx_addr;
306 	u16 last_avail_idx;
307 	u32 q_pair_id;
308 
309 	ifcvf_lm = (struct ifcvf_lm_cfg __iomem *)hw->lm_cfg;
310 	q_pair_id = qid / 2;
311 	avail_idx_addr = &ifcvf_lm->vring_lm_cfg[q_pair_id].idx_addr[qid % 2];
312 	last_avail_idx = vp_ioread16(avail_idx_addr);
313 
314 	return last_avail_idx;
315 }
316 
317 int ifcvf_set_vq_state(struct ifcvf_hw *hw, u16 qid, u16 num)
318 {
319 	struct ifcvf_lm_cfg __iomem *ifcvf_lm;
320 	void __iomem *avail_idx_addr;
321 	u32 q_pair_id;
322 
323 	ifcvf_lm = (struct ifcvf_lm_cfg __iomem *)hw->lm_cfg;
324 	q_pair_id = qid / 2;
325 	avail_idx_addr = &ifcvf_lm->vring_lm_cfg[q_pair_id].idx_addr[qid % 2];
326 	hw->vring[qid].last_avail_idx = num;
327 	vp_iowrite16(num, avail_idx_addr);
328 
329 	return 0;
330 }
331 
332 static int ifcvf_hw_enable(struct ifcvf_hw *hw)
333 {
334 	struct virtio_pci_common_cfg __iomem *cfg;
335 	u32 i;
336 
337 	cfg = hw->common_cfg;
338 	for (i = 0; i < hw->nr_vring; i++) {
339 		if (!hw->vring[i].ready)
340 			break;
341 
342 		vp_iowrite16(i, &cfg->queue_select);
343 		vp_iowrite64_twopart(hw->vring[i].desc, &cfg->queue_desc_lo,
344 				     &cfg->queue_desc_hi);
345 		vp_iowrite64_twopart(hw->vring[i].avail, &cfg->queue_avail_lo,
346 				      &cfg->queue_avail_hi);
347 		vp_iowrite64_twopart(hw->vring[i].used, &cfg->queue_used_lo,
348 				     &cfg->queue_used_hi);
349 		vp_iowrite16(hw->vring[i].size, &cfg->queue_size);
350 		ifcvf_set_vq_state(hw, i, hw->vring[i].last_avail_idx);
351 		vp_iowrite16(1, &cfg->queue_enable);
352 	}
353 
354 	return 0;
355 }
356 
357 static void ifcvf_hw_disable(struct ifcvf_hw *hw)
358 {
359 	u32 i;
360 
361 	ifcvf_set_config_vector(hw, VIRTIO_MSI_NO_VECTOR);
362 	for (i = 0; i < hw->nr_vring; i++) {
363 		ifcvf_set_vq_vector(hw, i, VIRTIO_MSI_NO_VECTOR);
364 	}
365 }
366 
367 int ifcvf_start_hw(struct ifcvf_hw *hw)
368 {
369 	ifcvf_reset(hw);
370 	ifcvf_add_status(hw, VIRTIO_CONFIG_S_ACKNOWLEDGE);
371 	ifcvf_add_status(hw, VIRTIO_CONFIG_S_DRIVER);
372 
373 	if (ifcvf_config_features(hw) < 0)
374 		return -EINVAL;
375 
376 	if (ifcvf_hw_enable(hw) < 0)
377 		return -EINVAL;
378 
379 	ifcvf_add_status(hw, VIRTIO_CONFIG_S_DRIVER_OK);
380 
381 	return 0;
382 }
383 
384 void ifcvf_stop_hw(struct ifcvf_hw *hw)
385 {
386 	ifcvf_hw_disable(hw);
387 	ifcvf_reset(hw);
388 }
389 
390 void ifcvf_notify_queue(struct ifcvf_hw *hw, u16 qid)
391 {
392 	vp_iowrite16(qid, hw->vring[qid].notify_addr);
393 }
394