1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
|
// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Copyright 2017 IBM Corporation
*/
#include <linux/clk.h>
#include <linux/mfd/syscon.h>
#include <linux/miscdevice.h>
#include <linux/mm.h>
#include <linux/module.h>
#include <linux/of_address.h>
#include <linux/platform_device.h>
#include <linux/poll.h>
#include <linux/regmap.h>
#include <linux/aspeed-lpc-ctrl.h>
#define DEVICE_NAME "aspeed-lpc-ctrl"
#define HICR5 0x0
#define HICR5_ENL2H BIT(8)
#define HICR5_ENFWH BIT(10)
#define HICR7 0x8
#define HICR8 0xc
struct aspeed_lpc_ctrl {
struct miscdevice miscdev;
struct regmap *regmap;
struct clk *clk;
phys_addr_t mem_base;
resource_size_t mem_size;
u32 pnor_size;
u32 pnor_base;
};
static struct aspeed_lpc_ctrl *file_aspeed_lpc_ctrl(struct file *file)
{
return container_of(file->private_data, struct aspeed_lpc_ctrl,
miscdev);
}
static int aspeed_lpc_ctrl_mmap(struct file *file, struct vm_area_struct *vma)
{
struct aspeed_lpc_ctrl *lpc_ctrl = file_aspeed_lpc_ctrl(file);
unsigned long vsize = vma->vm_end - vma->vm_start;
pgprot_t prot = vma->vm_page_prot;
if (vma->vm_pgoff + vsize > lpc_ctrl->mem_base + lpc_ctrl->mem_size)
return -EINVAL;
/* ast2400/2500 AHB accesses are not cache coherent */
prot = pgprot_noncached(prot);
if (remap_pfn_range(vma, vma->vm_start,
(lpc_ctrl->mem_base >> PAGE_SHIFT) + vma->vm_pgoff,
vsize, prot))
return -EAGAIN;
return 0;
}
static long aspeed_lpc_ctrl_ioctl(struct file *file, unsigned int cmd,
unsigned long param)
{
struct aspeed_lpc_ctrl *lpc_ctrl = file_aspeed_lpc_ctrl(file);
struct device *dev = file->private_data;
void __user *p = (void __user *)param;
struct aspeed_lpc_ctrl_mapping map;
u32 addr;
u32 size;
long rc;
if (copy_from_user(&map, p, sizeof(map)))
return -EFAULT;
if (map.flags != 0)
return -EINVAL;
switch (cmd) {
case ASPEED_LPC_CTRL_IOCTL_GET_SIZE:
/* The flash windows don't report their size */
if (map.window_type != ASPEED_LPC_CTRL_WINDOW_MEMORY)
return -EINVAL;
/* Support more than one window id in the future */
if (map.window_id != 0)
return -EINVAL;
/* If memory-region is not described in device tree */
if (!lpc_ctrl->mem_size) {
dev_dbg(dev, "Didn't find reserved memory\n");
return -ENXIO;
}
map.size = lpc_ctrl->mem_size;
return copy_to_user(p, &map, sizeof(map)) ? -EFAULT : 0;
case ASPEED_LPC_CTRL_IOCTL_MAP:
/*
* The top half of HICR7 is the MSB of the BMC address of the
* mapping.
* The bottom half of HICR7 is the MSB of the HOST LPC
* firmware space address of the mapping.
*
* The 1 bits in the top of half of HICR8 represent the bits
* (in the requested address) that should be ignored and
* replaced with those from the top half of HICR7.
* The 1 bits in the bottom half of HICR8 represent the bits
* (in the requested address) that should be kept and pass
* into the BMC address space.
*/
/*
* It doesn't make sense to talk about a size or offset with
* low 16 bits set. Both HICR7 and HICR8 talk about the top 16
* bits of addresses and sizes.
*/
if ((map.size & 0x0000ffff) || (map.offset & 0x0000ffff))
return -EINVAL;
/*
* Because of the way the masks work in HICR8 offset has to
* be a multiple of size.
*/
if (map.offset & (map.size - 1))
return -EINVAL;
if (map.window_type == ASPEED_LPC_CTRL_WINDOW_FLASH) {
if (!lpc_ctrl->pnor_size) {
dev_dbg(dev, "Didn't find host pnor flash\n");
return -ENXIO;
}
addr = lpc_ctrl->pnor_base;
size = lpc_ctrl->pnor_size;
} else if (map.window_type == ASPEED_LPC_CTRL_WINDOW_MEMORY) {
/* If memory-region is not described in device tree */
if (!lpc_ctrl->mem_size) {
dev_dbg(dev, "Didn't find reserved memory\n");
return -ENXIO;
}
addr = lpc_ctrl->mem_base;
size = lpc_ctrl->mem_size;
} else {
return -EINVAL;
}
/* Check overflow first! */
if (map.offset + map.size < map.offset ||
map.offset + map.size > size)
return -EINVAL;
if (map.size == 0 || map.size > size)
return -EINVAL;
addr += map.offset;
/*
* addr (host lpc address) is safe regardless of values. This
* simply changes the address the host has to request on its
* side of the LPC bus. This cannot impact the hosts own
* memory space by surprise as LPC specific accessors are
* required. The only strange thing that could be done is
* setting the lower 16 bits but the shift takes care of that.
*/
rc = regmap_write(lpc_ctrl->regmap, HICR7,
(addr | (map.addr >> 16)));
if (rc)
return rc;
rc = regmap_write(lpc_ctrl->regmap, HICR8,
(~(map.size - 1)) | ((map.size >> 16) - 1));
if (rc)
return rc;
/*
* Enable LPC FHW cycles. This is required for the host to
* access the regions specified.
*/
return regmap_update_bits(lpc_ctrl->regmap, HICR5,
HICR5_ENFWH | HICR5_ENL2H,
HICR5_ENFWH | HICR5_ENL2H);
}
return -EINVAL;
}
static const struct file_operations aspeed_lpc_ctrl_fops = {
.owner = THIS_MODULE,
.mmap = aspeed_lpc_ctrl_mmap,
.unlocked_ioctl = aspeed_lpc_ctrl_ioctl,
};
static int aspeed_lpc_ctrl_probe(struct platform_device *pdev)
{
struct aspeed_lpc_ctrl *lpc_ctrl;
struct device_node *node;
struct resource resm;
struct device *dev;
int rc;
dev = &pdev->dev;
lpc_ctrl = devm_kzalloc(dev, sizeof(*lpc_ctrl), GFP_KERNEL);
if (!lpc_ctrl)
return -ENOMEM;
/* If flash is described in device tree then store */
node = of_parse_phandle(dev->of_node, "flash", 0);
if (!node) {
dev_dbg(dev, "Didn't find host pnor flash node\n");
} else {
rc = of_address_to_resource(node, 1, &resm);
of_node_put(node);
if (rc) {
dev_err(dev, "Couldn't address to resource for flash\n");
return rc;
}
lpc_ctrl->pnor_size = resource_size(&resm);
lpc_ctrl->pnor_base = resm.start;
}
dev_set_drvdata(&pdev->dev, lpc_ctrl);
/* If memory-region is described in device tree then store */
node = of_parse_phandle(dev->of_node, "memory-region", 0);
if (!node) {
dev_dbg(dev, "Didn't find reserved memory\n");
} else {
rc = of_address_to_resource(node, 0, &resm);
of_node_put(node);
if (rc) {
dev_err(dev, "Couldn't address to resource for reserved memory\n");
return -ENXIO;
}
lpc_ctrl->mem_size = resource_size(&resm);
lpc_ctrl->mem_base = resm.start;
}
lpc_ctrl->regmap = syscon_node_to_regmap(
pdev->dev.parent->of_node);
if (IS_ERR(lpc_ctrl->regmap)) {
dev_err(dev, "Couldn't get regmap\n");
return -ENODEV;
}
lpc_ctrl->clk = devm_clk_get(dev, NULL);
if (IS_ERR(lpc_ctrl->clk)) {
dev_err(dev, "couldn't get clock\n");
return PTR_ERR(lpc_ctrl->clk);
}
rc = clk_prepare_enable(lpc_ctrl->clk);
if (rc) {
dev_err(dev, "couldn't enable clock\n");
return rc;
}
lpc_ctrl->miscdev.minor = MISC_DYNAMIC_MINOR;
lpc_ctrl->miscdev.name = DEVICE_NAME;
lpc_ctrl->miscdev.fops = &aspeed_lpc_ctrl_fops;
lpc_ctrl->miscdev.parent = dev;
rc = misc_register(&lpc_ctrl->miscdev);
if (rc) {
dev_err(dev, "Unable to register device\n");
goto err;
}
return 0;
err:
clk_disable_unprepare(lpc_ctrl->clk);
return rc;
}
static int aspeed_lpc_ctrl_remove(struct platform_device *pdev)
{
struct aspeed_lpc_ctrl *lpc_ctrl = dev_get_drvdata(&pdev->dev);
misc_deregister(&lpc_ctrl->miscdev);
clk_disable_unprepare(lpc_ctrl->clk);
return 0;
}
static const struct of_device_id aspeed_lpc_ctrl_match[] = {
{ .compatible = "aspeed,ast2400-lpc-ctrl" },
{ .compatible = "aspeed,ast2500-lpc-ctrl" },
{ .compatible = "aspeed,ast2600-lpc-ctrl" },
{ },
};
static struct platform_driver aspeed_lpc_ctrl_driver = {
.driver = {
.name = DEVICE_NAME,
.of_match_table = aspeed_lpc_ctrl_match,
},
.probe = aspeed_lpc_ctrl_probe,
.remove = aspeed_lpc_ctrl_remove,
};
module_platform_driver(aspeed_lpc_ctrl_driver);
MODULE_DEVICE_TABLE(of, aspeed_lpc_ctrl_match);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Cyril Bur <cyrilbur@gmail.com>");
MODULE_DESCRIPTION("Control for aspeed 2400/2500 LPC HOST to BMC mappings");
|