1 // SPDX-License-Identifier: GPL-2.0
2 /* Copyright(c) 2023 Advanced Micro Devices, Inc */
3 
4 #include <linux/pci.h>
5 
6 #include "core.h"
7 #include <linux/pds/pds_auxbus.h>
8 
9 /**
10  * pds_client_register - Link the client to the firmware
11  * @pf:		ptr to the PF driver's private data struct
12  * @devname:	name that includes service into, e.g. pds_core.vDPA
13  *
14  * Return: positive client ID (ci) on success, or
15  *         negative for error
16  */
pds_client_register(struct pdsc * pf,char * devname)17 int pds_client_register(struct pdsc *pf, char *devname)
18 {
19 	union pds_core_adminq_comp comp = {};
20 	union pds_core_adminq_cmd cmd = {};
21 	int err;
22 	u16 ci;
23 
24 	cmd.client_reg.opcode = PDS_AQ_CMD_CLIENT_REG;
25 	strscpy(cmd.client_reg.devname, devname,
26 		sizeof(cmd.client_reg.devname));
27 
28 	err = pdsc_adminq_post(pf, &cmd, &comp, false);
29 	if (err) {
30 		dev_info(pf->dev, "register dev_name %s with DSC failed, status %d: %pe\n",
31 			 devname, comp.status, ERR_PTR(err));
32 		return err;
33 	}
34 
35 	ci = le16_to_cpu(comp.client_reg.client_id);
36 	if (!ci) {
37 		dev_err(pf->dev, "%s: device returned null client_id\n",
38 			__func__);
39 		return -EIO;
40 	}
41 
42 	dev_dbg(pf->dev, "%s: device returned client_id %d for %s\n",
43 		__func__, ci, devname);
44 
45 	return ci;
46 }
47 EXPORT_SYMBOL_GPL(pds_client_register);
48 
49 /**
50  * pds_client_unregister - Unlink the client from the firmware
51  * @pf:		ptr to the PF driver's private data struct
52  * @client_id:	id returned from pds_client_register()
53  *
54  * Return: 0 on success, or
55  *         negative for error
56  */
pds_client_unregister(struct pdsc * pf,u16 client_id)57 int pds_client_unregister(struct pdsc *pf, u16 client_id)
58 {
59 	union pds_core_adminq_comp comp = {};
60 	union pds_core_adminq_cmd cmd = {};
61 	int err;
62 
63 	cmd.client_unreg.opcode = PDS_AQ_CMD_CLIENT_UNREG;
64 	cmd.client_unreg.client_id = cpu_to_le16(client_id);
65 
66 	err = pdsc_adminq_post(pf, &cmd, &comp, false);
67 	if (err)
68 		dev_info(pf->dev, "unregister client_id %d failed, status %d: %pe\n",
69 			 client_id, comp.status, ERR_PTR(err));
70 
71 	return err;
72 }
73 EXPORT_SYMBOL_GPL(pds_client_unregister);
74 
75 /**
76  * pds_client_adminq_cmd - Process an adminq request for the client
77  * @padev:   ptr to the client device
78  * @req:     ptr to buffer with request
79  * @req_len: length of actual struct used for request
80  * @resp:    ptr to buffer where answer is to be copied
81  * @flags:   optional flags from pds_core_adminq_flags
82  *
83  * Return: 0 on success, or
84  *         negative for error
85  *
86  * Client sends pointers to request and response buffers
87  * Core copies request data into pds_core_client_request_cmd
88  * Core sets other fields as needed
89  * Core posts to AdminQ
90  * Core copies completion data into response buffer
91  */
pds_client_adminq_cmd(struct pds_auxiliary_dev * padev,union pds_core_adminq_cmd * req,size_t req_len,union pds_core_adminq_comp * resp,u64 flags)92 int pds_client_adminq_cmd(struct pds_auxiliary_dev *padev,
93 			  union pds_core_adminq_cmd *req,
94 			  size_t req_len,
95 			  union pds_core_adminq_comp *resp,
96 			  u64 flags)
97 {
98 	union pds_core_adminq_cmd cmd = {};
99 	struct pci_dev *pf_pdev;
100 	struct pdsc *pf;
101 	size_t cp_len;
102 	int err;
103 
104 	pf_pdev = pci_physfn(padev->vf_pdev);
105 	pf = pci_get_drvdata(pf_pdev);
106 
107 	dev_dbg(pf->dev, "%s: %s opcode %d\n",
108 		__func__, dev_name(&padev->aux_dev.dev), req->opcode);
109 
110 	if (pf->state)
111 		return -ENXIO;
112 
113 	/* Wrap the client's request */
114 	cmd.client_request.opcode = PDS_AQ_CMD_CLIENT_CMD;
115 	cmd.client_request.client_id = cpu_to_le16(padev->client_id);
116 	cp_len = min_t(size_t, req_len, sizeof(cmd.client_request.client_cmd));
117 	memcpy(cmd.client_request.client_cmd, req, cp_len);
118 
119 	err = pdsc_adminq_post(pf, &cmd, resp,
120 			       !!(flags & PDS_AQ_FLAG_FASTPOLL));
121 	if (err && err != -EAGAIN)
122 		dev_info(pf->dev, "client admin cmd failed: %pe\n",
123 			 ERR_PTR(err));
124 
125 	return err;
126 }
127 EXPORT_SYMBOL_GPL(pds_client_adminq_cmd);
128 
pdsc_auxbus_dev_release(struct device * dev)129 static void pdsc_auxbus_dev_release(struct device *dev)
130 {
131 	struct pds_auxiliary_dev *padev =
132 		container_of(dev, struct pds_auxiliary_dev, aux_dev.dev);
133 
134 	kfree(padev);
135 }
136 
pdsc_auxbus_dev_register(struct pdsc * cf,struct pdsc * pf,u16 client_id,char * name)137 static struct pds_auxiliary_dev *pdsc_auxbus_dev_register(struct pdsc *cf,
138 							  struct pdsc *pf,
139 							  u16 client_id,
140 							  char *name)
141 {
142 	struct auxiliary_device *aux_dev;
143 	struct pds_auxiliary_dev *padev;
144 	int err;
145 
146 	padev = kzalloc(sizeof(*padev), GFP_KERNEL);
147 	if (!padev)
148 		return ERR_PTR(-ENOMEM);
149 
150 	padev->vf_pdev = cf->pdev;
151 	padev->client_id = client_id;
152 
153 	aux_dev = &padev->aux_dev;
154 	aux_dev->name = name;
155 	aux_dev->id = cf->uid;
156 	aux_dev->dev.parent = cf->dev;
157 	aux_dev->dev.release = pdsc_auxbus_dev_release;
158 
159 	err = auxiliary_device_init(aux_dev);
160 	if (err < 0) {
161 		dev_warn(cf->dev, "auxiliary_device_init of %s failed: %pe\n",
162 			 name, ERR_PTR(err));
163 		goto err_out;
164 	}
165 
166 	err = auxiliary_device_add(aux_dev);
167 	if (err) {
168 		dev_warn(cf->dev, "auxiliary_device_add of %s failed: %pe\n",
169 			 name, ERR_PTR(err));
170 		goto err_out_uninit;
171 	}
172 
173 	return padev;
174 
175 err_out_uninit:
176 	auxiliary_device_uninit(aux_dev);
177 err_out:
178 	kfree(padev);
179 	return ERR_PTR(err);
180 }
181 
pdsc_auxbus_dev_del(struct pdsc * cf,struct pdsc * pf)182 int pdsc_auxbus_dev_del(struct pdsc *cf, struct pdsc *pf)
183 {
184 	struct pds_auxiliary_dev *padev;
185 	int err = 0;
186 
187 	mutex_lock(&pf->config_lock);
188 
189 	padev = pf->vfs[cf->vf_id].padev;
190 	if (padev) {
191 		pds_client_unregister(pf, padev->client_id);
192 		auxiliary_device_delete(&padev->aux_dev);
193 		auxiliary_device_uninit(&padev->aux_dev);
194 		padev->client_id = 0;
195 	}
196 	pf->vfs[cf->vf_id].padev = NULL;
197 
198 	mutex_unlock(&pf->config_lock);
199 	return err;
200 }
201 
pdsc_auxbus_dev_add(struct pdsc * cf,struct pdsc * pf)202 int pdsc_auxbus_dev_add(struct pdsc *cf, struct pdsc *pf)
203 {
204 	struct pds_auxiliary_dev *padev;
205 	enum pds_core_vif_types vt;
206 	char devname[PDS_DEVNAME_LEN];
207 	u16 vt_support;
208 	int client_id;
209 	int err = 0;
210 
211 	mutex_lock(&pf->config_lock);
212 
213 	/* We only support vDPA so far, so it is the only one to
214 	 * be verified that it is available in the Core device and
215 	 * enabled in the devlink param.  In the future this might
216 	 * become a loop for several VIF types.
217 	 */
218 
219 	/* Verify that the type is supported and enabled.  It is not
220 	 * an error if there is no auxbus device support for this
221 	 * VF, it just means something else needs to happen with it.
222 	 */
223 	vt = PDS_DEV_TYPE_VDPA;
224 	vt_support = !!le16_to_cpu(pf->dev_ident.vif_types[vt]);
225 	if (!(vt_support &&
226 	      pf->viftype_status[vt].supported &&
227 	      pf->viftype_status[vt].enabled))
228 		goto out_unlock;
229 
230 	/* Need to register with FW and get the client_id before
231 	 * creating the aux device so that the aux client can run
232 	 * adminq commands as part its probe
233 	 */
234 	snprintf(devname, sizeof(devname), "%s.%s.%d",
235 		 PDS_CORE_DRV_NAME, pf->viftype_status[vt].name, cf->uid);
236 	client_id = pds_client_register(pf, devname);
237 	if (client_id < 0) {
238 		err = client_id;
239 		goto out_unlock;
240 	}
241 
242 	padev = pdsc_auxbus_dev_register(cf, pf, client_id,
243 					 pf->viftype_status[vt].name);
244 	if (IS_ERR(padev)) {
245 		pds_client_unregister(pf, client_id);
246 		err = PTR_ERR(padev);
247 		goto out_unlock;
248 	}
249 	pf->vfs[cf->vf_id].padev = padev;
250 
251 out_unlock:
252 	mutex_unlock(&pf->config_lock);
253 	return err;
254 }
255