xref: /openbmc/linux/drivers/bus/fsl-mc/mc-io.c (revision b830f94f)
1 // SPDX-License-Identifier: (GPL-2.0+ OR BSD-3-Clause)
2 /*
3  * Copyright 2013-2016 Freescale Semiconductor Inc.
4  *
5  */
6 
7 #include <linux/io.h>
8 #include <linux/fsl/mc.h>
9 
10 #include "fsl-mc-private.h"
11 
12 static int fsl_mc_io_set_dpmcp(struct fsl_mc_io *mc_io,
13 			       struct fsl_mc_device *dpmcp_dev)
14 {
15 	int error;
16 
17 	if (mc_io->dpmcp_dev)
18 		return -EINVAL;
19 
20 	if (dpmcp_dev->mc_io)
21 		return -EINVAL;
22 
23 	error = dpmcp_open(mc_io,
24 			   0,
25 			   dpmcp_dev->obj_desc.id,
26 			   &dpmcp_dev->mc_handle);
27 	if (error < 0)
28 		return error;
29 
30 	mc_io->dpmcp_dev = dpmcp_dev;
31 	dpmcp_dev->mc_io = mc_io;
32 	return 0;
33 }
34 
35 static void fsl_mc_io_unset_dpmcp(struct fsl_mc_io *mc_io)
36 {
37 	int error;
38 	struct fsl_mc_device *dpmcp_dev = mc_io->dpmcp_dev;
39 
40 	error = dpmcp_close(mc_io,
41 			    0,
42 			    dpmcp_dev->mc_handle);
43 	if (error < 0) {
44 		dev_err(&dpmcp_dev->dev, "dpmcp_close() failed: %d\n",
45 			error);
46 	}
47 
48 	mc_io->dpmcp_dev = NULL;
49 	dpmcp_dev->mc_io = NULL;
50 }
51 
52 /**
53  * Creates an MC I/O object
54  *
55  * @dev: device to be associated with the MC I/O object
56  * @mc_portal_phys_addr: physical address of the MC portal to use
57  * @mc_portal_size: size in bytes of the MC portal
58  * @dpmcp-dev: Pointer to the DPMCP object associated with this MC I/O
59  * object or NULL if none.
60  * @flags: flags for the new MC I/O object
61  * @new_mc_io: Area to return pointer to newly created MC I/O object
62  *
63  * Returns '0' on Success; Error code otherwise.
64  */
65 int __must_check fsl_create_mc_io(struct device *dev,
66 				  phys_addr_t mc_portal_phys_addr,
67 				  u32 mc_portal_size,
68 				  struct fsl_mc_device *dpmcp_dev,
69 				  u32 flags, struct fsl_mc_io **new_mc_io)
70 {
71 	int error;
72 	struct fsl_mc_io *mc_io;
73 	void __iomem *mc_portal_virt_addr;
74 	struct resource *res;
75 
76 	mc_io = devm_kzalloc(dev, sizeof(*mc_io), GFP_KERNEL);
77 	if (!mc_io)
78 		return -ENOMEM;
79 
80 	mc_io->dev = dev;
81 	mc_io->flags = flags;
82 	mc_io->portal_phys_addr = mc_portal_phys_addr;
83 	mc_io->portal_size = mc_portal_size;
84 	if (flags & FSL_MC_IO_ATOMIC_CONTEXT_PORTAL)
85 		spin_lock_init(&mc_io->spinlock);
86 	else
87 		mutex_init(&mc_io->mutex);
88 
89 	res = devm_request_mem_region(dev,
90 				      mc_portal_phys_addr,
91 				      mc_portal_size,
92 				      "mc_portal");
93 	if (!res) {
94 		dev_err(dev,
95 			"devm_request_mem_region failed for MC portal %pa\n",
96 			&mc_portal_phys_addr);
97 		return -EBUSY;
98 	}
99 
100 	mc_portal_virt_addr = devm_ioremap_nocache(dev,
101 						   mc_portal_phys_addr,
102 						   mc_portal_size);
103 	if (!mc_portal_virt_addr) {
104 		dev_err(dev,
105 			"devm_ioremap_nocache failed for MC portal %pa\n",
106 			&mc_portal_phys_addr);
107 		return -ENXIO;
108 	}
109 
110 	mc_io->portal_virt_addr = mc_portal_virt_addr;
111 	if (dpmcp_dev) {
112 		error = fsl_mc_io_set_dpmcp(mc_io, dpmcp_dev);
113 		if (error < 0)
114 			goto error_destroy_mc_io;
115 	}
116 
117 	*new_mc_io = mc_io;
118 	return 0;
119 
120 error_destroy_mc_io:
121 	fsl_destroy_mc_io(mc_io);
122 	return error;
123 }
124 
125 /**
126  * Destroys an MC I/O object
127  *
128  * @mc_io: MC I/O object to destroy
129  */
130 void fsl_destroy_mc_io(struct fsl_mc_io *mc_io)
131 {
132 	struct fsl_mc_device *dpmcp_dev = mc_io->dpmcp_dev;
133 
134 	if (dpmcp_dev)
135 		fsl_mc_io_unset_dpmcp(mc_io);
136 
137 	devm_iounmap(mc_io->dev, mc_io->portal_virt_addr);
138 	devm_release_mem_region(mc_io->dev,
139 				mc_io->portal_phys_addr,
140 				mc_io->portal_size);
141 
142 	mc_io->portal_virt_addr = NULL;
143 	devm_kfree(mc_io->dev, mc_io);
144 }
145 
146 /**
147  * fsl_mc_portal_allocate - Allocates an MC portal
148  *
149  * @mc_dev: MC device for which the MC portal is to be allocated
150  * @mc_io_flags: Flags for the fsl_mc_io object that wraps the allocated
151  * MC portal.
152  * @new_mc_io: Pointer to area where the pointer to the fsl_mc_io object
153  * that wraps the allocated MC portal is to be returned
154  *
155  * This function allocates an MC portal from the device's parent DPRC,
156  * from the corresponding MC bus' pool of MC portals and wraps
157  * it in a new fsl_mc_io object. If 'mc_dev' is a DPRC itself, the
158  * portal is allocated from its own MC bus.
159  */
160 int __must_check fsl_mc_portal_allocate(struct fsl_mc_device *mc_dev,
161 					u16 mc_io_flags,
162 					struct fsl_mc_io **new_mc_io)
163 {
164 	struct fsl_mc_device *mc_bus_dev;
165 	struct fsl_mc_bus *mc_bus;
166 	phys_addr_t mc_portal_phys_addr;
167 	size_t mc_portal_size;
168 	struct fsl_mc_device *dpmcp_dev;
169 	int error = -EINVAL;
170 	struct fsl_mc_resource *resource = NULL;
171 	struct fsl_mc_io *mc_io = NULL;
172 
173 	if (mc_dev->flags & FSL_MC_IS_DPRC) {
174 		mc_bus_dev = mc_dev;
175 	} else {
176 		if (!dev_is_fsl_mc(mc_dev->dev.parent))
177 			return error;
178 
179 		mc_bus_dev = to_fsl_mc_device(mc_dev->dev.parent);
180 	}
181 
182 	mc_bus = to_fsl_mc_bus(mc_bus_dev);
183 	*new_mc_io = NULL;
184 	error = fsl_mc_resource_allocate(mc_bus, FSL_MC_POOL_DPMCP, &resource);
185 	if (error < 0)
186 		return error;
187 
188 	error = -EINVAL;
189 	dpmcp_dev = resource->data;
190 
191 	if (dpmcp_dev->obj_desc.ver_major < DPMCP_MIN_VER_MAJOR ||
192 	    (dpmcp_dev->obj_desc.ver_major == DPMCP_MIN_VER_MAJOR &&
193 	     dpmcp_dev->obj_desc.ver_minor < DPMCP_MIN_VER_MINOR)) {
194 		dev_err(&dpmcp_dev->dev,
195 			"ERROR: Version %d.%d of DPMCP not supported.\n",
196 			dpmcp_dev->obj_desc.ver_major,
197 			dpmcp_dev->obj_desc.ver_minor);
198 		error = -ENOTSUPP;
199 		goto error_cleanup_resource;
200 	}
201 
202 	mc_portal_phys_addr = dpmcp_dev->regions[0].start;
203 	mc_portal_size = resource_size(dpmcp_dev->regions);
204 
205 	error = fsl_create_mc_io(&mc_bus_dev->dev,
206 				 mc_portal_phys_addr,
207 				 mc_portal_size, dpmcp_dev,
208 				 mc_io_flags, &mc_io);
209 	if (error < 0)
210 		goto error_cleanup_resource;
211 
212 	dpmcp_dev->consumer_link = device_link_add(&mc_dev->dev,
213 						   &dpmcp_dev->dev,
214 						   DL_FLAG_AUTOREMOVE_CONSUMER);
215 	if (!dpmcp_dev->consumer_link) {
216 		error = -EINVAL;
217 		goto error_cleanup_mc_io;
218 	}
219 
220 	*new_mc_io = mc_io;
221 	return 0;
222 
223 error_cleanup_mc_io:
224 	fsl_destroy_mc_io(mc_io);
225 error_cleanup_resource:
226 	fsl_mc_resource_free(resource);
227 	return error;
228 }
229 EXPORT_SYMBOL_GPL(fsl_mc_portal_allocate);
230 
231 /**
232  * fsl_mc_portal_free - Returns an MC portal to the pool of free MC portals
233  * of a given MC bus
234  *
235  * @mc_io: Pointer to the fsl_mc_io object that wraps the MC portal to free
236  */
237 void fsl_mc_portal_free(struct fsl_mc_io *mc_io)
238 {
239 	struct fsl_mc_device *dpmcp_dev;
240 	struct fsl_mc_resource *resource;
241 
242 	/*
243 	 * Every mc_io obtained by calling fsl_mc_portal_allocate() is supposed
244 	 * to have a DPMCP object associated with.
245 	 */
246 	dpmcp_dev = mc_io->dpmcp_dev;
247 
248 	resource = dpmcp_dev->resource;
249 	if (!resource || resource->type != FSL_MC_POOL_DPMCP)
250 		return;
251 
252 	if (resource->data != dpmcp_dev)
253 		return;
254 
255 	fsl_destroy_mc_io(mc_io);
256 	fsl_mc_resource_free(resource);
257 
258 	device_link_del(dpmcp_dev->consumer_link);
259 	dpmcp_dev->consumer_link = NULL;
260 }
261 EXPORT_SYMBOL_GPL(fsl_mc_portal_free);
262 
263 /**
264  * fsl_mc_portal_reset - Resets the dpmcp object for a given fsl_mc_io object
265  *
266  * @mc_io: Pointer to the fsl_mc_io object that wraps the MC portal to free
267  */
268 int fsl_mc_portal_reset(struct fsl_mc_io *mc_io)
269 {
270 	int error;
271 	struct fsl_mc_device *dpmcp_dev = mc_io->dpmcp_dev;
272 
273 	error = dpmcp_reset(mc_io, 0, dpmcp_dev->mc_handle);
274 	if (error < 0) {
275 		dev_err(&dpmcp_dev->dev, "dpmcp_reset() failed: %d\n", error);
276 		return error;
277 	}
278 
279 	return 0;
280 }
281 EXPORT_SYMBOL_GPL(fsl_mc_portal_reset);
282