xref: /openbmc/linux/drivers/vdpa/ifcvf/ifcvf_base.c (revision 12cecbf9) 
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 struct ifcvf_adapter *vf_to_adapter(struct ifcvf_hw *hw)
14 {
15 	return container_of(hw, struct ifcvf_adapter, vf);
16 }
17 
18 u16 ifcvf_set_vq_vector(struct ifcvf_hw *hw, u16 qid, int vector)
19 {
20 	struct virtio_pci_common_cfg __iomem *cfg = hw->common_cfg;
21 
22 	vp_iowrite16(qid, &cfg->queue_select);
23 	vp_iowrite16(vector, &cfg->queue_msix_vector);
24 
25 	return vp_ioread16(&cfg->queue_msix_vector);
26 }
27 
28 u16 ifcvf_set_config_vector(struct ifcvf_hw *hw, int vector)
29 {
30 	struct virtio_pci_common_cfg __iomem *cfg = hw->common_cfg;
31 
32 	vp_iowrite16(vector,  &cfg->msix_config);
33 
34 	return vp_ioread16(&cfg->msix_config);
35 }
36 
37 static void __iomem *get_cap_addr(struct ifcvf_hw *hw,
38 				  struct virtio_pci_cap *cap)
39 {
40 	struct ifcvf_adapter *ifcvf;
41 	struct pci_dev *pdev;
42 	u32 length, offset;
43 	u8 bar;
44 
45 	length = le32_to_cpu(cap->length);
46 	offset = le32_to_cpu(cap->offset);
47 	bar = cap->bar;
48 
49 	ifcvf= vf_to_adapter(hw);
50 	pdev = ifcvf->pdev;
51 
52 	if (bar >= IFCVF_PCI_MAX_RESOURCE) {
53 		IFCVF_DBG(pdev,
54 			  "Invalid bar number %u to get capabilities\n", bar);
55 		return NULL;
56 	}
57 
58 	if (offset + length > pci_resource_len(pdev, bar)) {
59 		IFCVF_DBG(pdev,
60 			  "offset(%u) + len(%u) overflows bar%u's capability\n",
61 			  offset, length, bar);
62 		return NULL;
63 	}
64 
65 	return hw->base[bar] + offset;
66 }
67 
68 static int ifcvf_read_config_range(struct pci_dev *dev,
69 				   uint32_t *val, int size, int where)
70 {
71 	int ret, i;
72 
73 	for (i = 0; i < size; i += 4) {
74 		ret = pci_read_config_dword(dev, where + i, val + i / 4);
75 		if (ret < 0)
76 			return ret;
77 	}
78 
79 	return 0;
80 }
81 
82 int ifcvf_init_hw(struct ifcvf_hw *hw, struct pci_dev *pdev)
83 {
84 	struct virtio_pci_cap cap;
85 	u16 notify_off;
86 	int ret;
87 	u8 pos;
88 	u32 i;
89 
90 	ret = pci_read_config_byte(pdev, PCI_CAPABILITY_LIST, &pos);
91 	if (ret < 0) {
92 		IFCVF_ERR(pdev, "Failed to read PCI capability list\n");
93 		return -EIO;
94 	}
95 
96 	while (pos) {
97 		ret = ifcvf_read_config_range(pdev, (u32 *)&cap,
98 					      sizeof(cap), pos);
99 		if (ret < 0) {
100 			IFCVF_ERR(pdev,
101 				  "Failed to get PCI capability at %x\n", pos);
102 			break;
103 		}
104 
105 		if (cap.cap_vndr != PCI_CAP_ID_VNDR)
106 			goto next;
107 
108 		switch (cap.cfg_type) {
109 		case VIRTIO_PCI_CAP_COMMON_CFG:
110 			hw->common_cfg = get_cap_addr(hw, &cap);
111 			IFCVF_DBG(pdev, "hw->common_cfg = %p\n",
112 				  hw->common_cfg);
113 			break;
114 		case VIRTIO_PCI_CAP_NOTIFY_CFG:
115 			pci_read_config_dword(pdev, pos + sizeof(cap),
116 					      &hw->notify_off_multiplier);
117 			hw->notify_bar = cap.bar;
118 			hw->notify_base = get_cap_addr(hw, &cap);
119 			hw->notify_base_pa = pci_resource_start(pdev, cap.bar) +
120 					le32_to_cpu(cap.offset);
121 			IFCVF_DBG(pdev, "hw->notify_base = %p\n",
122 				  hw->notify_base);
123 			break;
124 		case VIRTIO_PCI_CAP_ISR_CFG:
125 			hw->isr = get_cap_addr(hw, &cap);
126 			IFCVF_DBG(pdev, "hw->isr = %p\n", hw->isr);
127 			break;
128 		case VIRTIO_PCI_CAP_DEVICE_CFG:
129 			hw->dev_cfg = get_cap_addr(hw, &cap);
130 			hw->cap_dev_config_size = le32_to_cpu(cap.length);
131 			IFCVF_DBG(pdev, "hw->dev_cfg = %p\n", hw->dev_cfg);
132 			break;
133 		}
134 
135 next:
136 		pos = cap.cap_next;
137 	}
138 
139 	if (hw->common_cfg == NULL || hw->notify_base == NULL ||
140 	    hw->isr == NULL || hw->dev_cfg == NULL) {
141 		IFCVF_ERR(pdev, "Incomplete PCI capabilities\n");
142 		return -EIO;
143 	}
144 
145 	hw->nr_vring = vp_ioread16(&hw->common_cfg->num_queues);
146 
147 	for (i = 0; i < hw->nr_vring; i++) {
148 		vp_iowrite16(i, &hw->common_cfg->queue_select);
149 		notify_off = vp_ioread16(&hw->common_cfg->queue_notify_off);
150 		hw->vring[i].notify_addr = hw->notify_base +
151 			notify_off * hw->notify_off_multiplier;
152 		hw->vring[i].notify_pa = hw->notify_base_pa +
153 			notify_off * hw->notify_off_multiplier;
154 		hw->vring[i].irq = -EINVAL;
155 	}
156 
157 	hw->lm_cfg = hw->base[IFCVF_LM_BAR];
158 
159 	IFCVF_DBG(pdev,
160 		  "PCI capability mapping: common cfg: %p, notify base: %p\n, isr cfg: %p, device cfg: %p, multiplier: %u\n",
161 		  hw->common_cfg, hw->notify_base, hw->isr,
162 		  hw->dev_cfg, hw->notify_off_multiplier);
163 
164 	hw->vqs_reused_irq = -EINVAL;
165 	hw->config_irq = -EINVAL;
166 
167 	return 0;
168 }
169 
170 u8 ifcvf_get_status(struct ifcvf_hw *hw)
171 {
172 	return vp_ioread8(&hw->common_cfg->device_status);
173 }
174 
175 void ifcvf_set_status(struct ifcvf_hw *hw, u8 status)
176 {
177 	vp_iowrite8(status, &hw->common_cfg->device_status);
178 }
179 
180 void ifcvf_reset(struct ifcvf_hw *hw)
181 {
182 	hw->config_cb.callback = NULL;
183 	hw->config_cb.private = NULL;
184 
185 	ifcvf_set_status(hw, 0);
186 	/* flush set_status, make sure VF is stopped, reset */
187 	ifcvf_get_status(hw);
188 }
189 
190 static void ifcvf_add_status(struct ifcvf_hw *hw, u8 status)
191 {
192 	if (status != 0)
193 		status |= ifcvf_get_status(hw);
194 
195 	ifcvf_set_status(hw, status);
196 	ifcvf_get_status(hw);
197 }
198 
199 u64 ifcvf_get_hw_features(struct ifcvf_hw *hw)
200 {
201 	struct virtio_pci_common_cfg __iomem *cfg = hw->common_cfg;
202 	u32 features_lo, features_hi;
203 	u64 features;
204 
205 	vp_iowrite32(0, &cfg->device_feature_select);
206 	features_lo = vp_ioread32(&cfg->device_feature);
207 
208 	vp_iowrite32(1, &cfg->device_feature_select);
209 	features_hi = vp_ioread32(&cfg->device_feature);
210 
211 	features = ((u64)features_hi << 32) | features_lo;
212 
213 	return features;
214 }
215 
216 u64 ifcvf_get_features(struct ifcvf_hw *hw)
217 {
218 	return hw->hw_features;
219 }
220 
221 int ifcvf_verify_min_features(struct ifcvf_hw *hw, u64 features)
222 {
223 	struct ifcvf_adapter *ifcvf = vf_to_adapter(hw);
224 
225 	if (!(features & BIT_ULL(VIRTIO_F_ACCESS_PLATFORM)) && features) {
226 		IFCVF_ERR(ifcvf->pdev, "VIRTIO_F_ACCESS_PLATFORM is not negotiated\n");
227 		return -EINVAL;
228 	}
229 
230 	return 0;
231 }
232 
233 u32 ifcvf_get_config_size(struct ifcvf_hw *hw)
234 {
235 	struct ifcvf_adapter *adapter;
236 	u32 net_config_size = sizeof(struct virtio_net_config);
237 	u32 blk_config_size = sizeof(struct virtio_blk_config);
238 	u32 cap_size = hw->cap_dev_config_size;
239 	u32 config_size;
240 
241 	adapter = vf_to_adapter(hw);
242 	/* If the onboard device config space size is greater than
243 	 * the size of struct virtio_net/blk_config, only the spec
244 	 * implementing contents size is returned, this is very
245 	 * unlikely, defensive programming.
246 	 */
247 	switch (hw->dev_type) {
248 	case VIRTIO_ID_NET:
249 		config_size = min(cap_size, net_config_size);
250 		break;
251 	case VIRTIO_ID_BLOCK:
252 		config_size = min(cap_size, blk_config_size);
253 		break;
254 	default:
255 		config_size = 0;
256 		IFCVF_ERR(adapter->pdev, "VIRTIO ID %u not supported\n", hw->dev_type);
257 	}
258 
259 	return config_size;
260 }
261 
262 void ifcvf_read_dev_config(struct ifcvf_hw *hw, u64 offset,
263 			   void *dst, int length)
264 {
265 	u8 old_gen, new_gen, *p;
266 	int i;
267 
268 	WARN_ON(offset + length > hw->config_size);
269 	do {
270 		old_gen = vp_ioread8(&hw->common_cfg->config_generation);
271 		p = dst;
272 		for (i = 0; i < length; i++)
273 			*p++ = vp_ioread8(hw->dev_cfg + offset + i);
274 
275 		new_gen = vp_ioread8(&hw->common_cfg->config_generation);
276 	} while (old_gen != new_gen);
277 }
278 
279 void ifcvf_write_dev_config(struct ifcvf_hw *hw, u64 offset,
280 			    const void *src, int length)
281 {
282 	const u8 *p;
283 	int i;
284 
285 	p = src;
286 	WARN_ON(offset + length > hw->config_size);
287 	for (i = 0; i < length; i++)
288 		vp_iowrite8(*p++, hw->dev_cfg + offset + i);
289 }
290 
291 static void ifcvf_set_features(struct ifcvf_hw *hw, u64 features)
292 {
293 	struct virtio_pci_common_cfg __iomem *cfg = hw->common_cfg;
294 
295 	vp_iowrite32(0, &cfg->guest_feature_select);
296 	vp_iowrite32((u32)features, &cfg->guest_feature);
297 
298 	vp_iowrite32(1, &cfg->guest_feature_select);
299 	vp_iowrite32(features >> 32, &cfg->guest_feature);
300 }
301 
302 static int ifcvf_config_features(struct ifcvf_hw *hw)
303 {
304 	struct ifcvf_adapter *ifcvf;
305 
306 	ifcvf = vf_to_adapter(hw);
307 	ifcvf_set_features(hw, hw->req_features);
308 	ifcvf_add_status(hw, VIRTIO_CONFIG_S_FEATURES_OK);
309 
310 	if (!(ifcvf_get_status(hw) & VIRTIO_CONFIG_S_FEATURES_OK)) {
311 		IFCVF_ERR(ifcvf->pdev, "Failed to set FEATURES_OK status\n");
312 		return -EIO;
313 	}
314 
315 	return 0;
316 }
317 
318 u16 ifcvf_get_vq_state(struct ifcvf_hw *hw, u16 qid)
319 {
320 	struct ifcvf_lm_cfg __iomem *ifcvf_lm;
321 	void __iomem *avail_idx_addr;
322 	u16 last_avail_idx;
323 	u32 q_pair_id;
324 
325 	ifcvf_lm = (struct ifcvf_lm_cfg __iomem *)hw->lm_cfg;
326 	q_pair_id = qid / hw->nr_vring;
327 	avail_idx_addr = &ifcvf_lm->vring_lm_cfg[q_pair_id].idx_addr[qid % 2];
328 	last_avail_idx = vp_ioread16(avail_idx_addr);
329 
330 	return last_avail_idx;
331 }
332 
333 int ifcvf_set_vq_state(struct ifcvf_hw *hw, u16 qid, u16 num)
334 {
335 	struct ifcvf_lm_cfg __iomem *ifcvf_lm;
336 	void __iomem *avail_idx_addr;
337 	u32 q_pair_id;
338 
339 	ifcvf_lm = (struct ifcvf_lm_cfg __iomem *)hw->lm_cfg;
340 	q_pair_id = qid / hw->nr_vring;
341 	avail_idx_addr = &ifcvf_lm->vring_lm_cfg[q_pair_id].idx_addr[qid % 2];
342 	hw->vring[qid].last_avail_idx = num;
343 	vp_iowrite16(num, avail_idx_addr);
344 
345 	return 0;
346 }
347 
348 static int ifcvf_hw_enable(struct ifcvf_hw *hw)
349 {
350 	struct virtio_pci_common_cfg __iomem *cfg;
351 	u32 i;
352 
353 	cfg = hw->common_cfg;
354 	for (i = 0; i < hw->nr_vring; i++) {
355 		if (!hw->vring[i].ready)
356 			break;
357 
358 		vp_iowrite16(i, &cfg->queue_select);
359 		vp_iowrite64_twopart(hw->vring[i].desc, &cfg->queue_desc_lo,
360 				     &cfg->queue_desc_hi);
361 		vp_iowrite64_twopart(hw->vring[i].avail, &cfg->queue_avail_lo,
362 				      &cfg->queue_avail_hi);
363 		vp_iowrite64_twopart(hw->vring[i].used, &cfg->queue_used_lo,
364 				     &cfg->queue_used_hi);
365 		vp_iowrite16(hw->vring[i].size, &cfg->queue_size);
366 		ifcvf_set_vq_state(hw, i, hw->vring[i].last_avail_idx);
367 		vp_iowrite16(1, &cfg->queue_enable);
368 	}
369 
370 	return 0;
371 }
372 
373 static void ifcvf_hw_disable(struct ifcvf_hw *hw)
374 {
375 	u32 i;
376 
377 	ifcvf_set_config_vector(hw, VIRTIO_MSI_NO_VECTOR);
378 	for (i = 0; i < hw->nr_vring; i++) {
379 		ifcvf_set_vq_vector(hw, i, VIRTIO_MSI_NO_VECTOR);
380 	}
381 }
382 
383 int ifcvf_start_hw(struct ifcvf_hw *hw)
384 {
385 	ifcvf_reset(hw);
386 	ifcvf_add_status(hw, VIRTIO_CONFIG_S_ACKNOWLEDGE);
387 	ifcvf_add_status(hw, VIRTIO_CONFIG_S_DRIVER);
388 
389 	if (ifcvf_config_features(hw) < 0)
390 		return -EINVAL;
391 
392 	if (ifcvf_hw_enable(hw) < 0)
393 		return -EINVAL;
394 
395 	ifcvf_add_status(hw, VIRTIO_CONFIG_S_DRIVER_OK);
396 
397 	return 0;
398 }
399 
400 void ifcvf_stop_hw(struct ifcvf_hw *hw)
401 {
402 	ifcvf_hw_disable(hw);
403 	ifcvf_reset(hw);
404 }
405 
406 void ifcvf_notify_queue(struct ifcvf_hw *hw, u16 qid)
407 {
408 	vp_iowrite16(qid, hw->vring[qid].notify_addr);
409 }
410