xref: /openbmc/linux/drivers/bus/fsl-mc/mc-io.c (revision 7f904d7e1f3ec7c2de47c024a5a5c30988b54703)
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