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 */
17int 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}
47EXPORT_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 */
57int 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}
73EXPORT_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 */
92int 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}
127EXPORT_SYMBOL_GPL(pds_client_adminq_cmd);
128
129static 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
137static 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		kfree(padev);
164		return ERR_PTR(err);
165	}
166
167	err = auxiliary_device_add(aux_dev);
168	if (err) {
169		dev_warn(cf->dev, "auxiliary_device_add of %s failed: %pe\n",
170			 name, ERR_PTR(err));
171		auxiliary_device_uninit(aux_dev);
172		return ERR_PTR(err);
173	}
174
175	return padev;
176}
177
178int pdsc_auxbus_dev_del(struct pdsc *cf, struct pdsc *pf)
179{
180	struct pds_auxiliary_dev *padev;
181	int err = 0;
182
183	if (!cf)
184		return -ENODEV;
185
186	mutex_lock(&pf->config_lock);
187
188	padev = pf->vfs[cf->vf_id].padev;
189	if (padev) {
190		pds_client_unregister(pf, padev->client_id);
191		auxiliary_device_delete(&padev->aux_dev);
192		auxiliary_device_uninit(&padev->aux_dev);
193		padev->client_id = 0;
194	}
195	pf->vfs[cf->vf_id].padev = NULL;
196
197	mutex_unlock(&pf->config_lock);
198	return err;
199}
200
201int pdsc_auxbus_dev_add(struct pdsc *cf, struct pdsc *pf)
202{
203	struct pds_auxiliary_dev *padev;
204	char devname[PDS_DEVNAME_LEN];
205	enum pds_core_vif_types vt;
206	unsigned long mask;
207	u16 vt_support;
208	int client_id;
209	int err = 0;
210
211	if (!cf)
212		return -ENODEV;
213
214	mutex_lock(&pf->config_lock);
215
216	mask = BIT_ULL(PDSC_S_FW_DEAD) |
217	       BIT_ULL(PDSC_S_STOPPING_DRIVER);
218	if (cf->state & mask) {
219		dev_err(pf->dev, "%s: can't add dev, VF client in bad state %#lx\n",
220			__func__, cf->state);
221		err = -ENXIO;
222		goto out_unlock;
223	}
224
225	/* We only support vDPA so far, so it is the only one to
226	 * be verified that it is available in the Core device and
227	 * enabled in the devlink param.  In the future this might
228	 * become a loop for several VIF types.
229	 */
230
231	/* Verify that the type is supported and enabled.  It is not
232	 * an error if there is no auxbus device support for this
233	 * VF, it just means something else needs to happen with it.
234	 */
235	vt = PDS_DEV_TYPE_VDPA;
236	vt_support = !!le16_to_cpu(pf->dev_ident.vif_types[vt]);
237	if (!(vt_support &&
238	      pf->viftype_status[vt].supported &&
239	      pf->viftype_status[vt].enabled))
240		goto out_unlock;
241
242	/* Need to register with FW and get the client_id before
243	 * creating the aux device so that the aux client can run
244	 * adminq commands as part its probe
245	 */
246	snprintf(devname, sizeof(devname), "%s.%s.%d",
247		 PDS_CORE_DRV_NAME, pf->viftype_status[vt].name, cf->uid);
248	client_id = pds_client_register(pf, devname);
249	if (client_id < 0) {
250		err = client_id;
251		goto out_unlock;
252	}
253
254	padev = pdsc_auxbus_dev_register(cf, pf, client_id,
255					 pf->viftype_status[vt].name);
256	if (IS_ERR(padev)) {
257		pds_client_unregister(pf, client_id);
258		err = PTR_ERR(padev);
259		goto out_unlock;
260	}
261	pf->vfs[cf->vf_id].padev = padev;
262
263out_unlock:
264	mutex_unlock(&pf->config_lock);
265	return err;
266}
267