xref: /openbmc/u-boot/drivers/misc/swap_case.c (revision 286a5c44)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * PCI emulation device which swaps the case of text
4  *
5  * Copyright (c) 2014 Google, Inc
6  * Written by Simon Glass <sjg@chromium.org>
7  */
8 
9 #include <common.h>
10 #include <dm.h>
11 #include <errno.h>
12 #include <pci.h>
13 #include <asm/test.h>
14 #include <linux/ctype.h>
15 
16 /**
17  * struct swap_case_platdata - platform data for this device
18  *
19  * @command:	Current PCI command value
20  * @bar:	Current base address values
21  */
22 struct swap_case_platdata {
23 	u16 command;
24 	u32 bar[6];
25 };
26 
27 #define offset_to_barnum(offset)	\
28 		(((offset) - PCI_BASE_ADDRESS_0) / sizeof(u32))
29 
30 enum {
31 	MEM_TEXT_SIZE	= 0x100,
32 };
33 
34 enum swap_case_op {
35 	OP_TO_LOWER,
36 	OP_TO_UPPER,
37 	OP_SWAP,
38 };
39 
40 static struct pci_bar {
41 	int type;
42 	u32 size;
43 } barinfo[] = {
44 	{ PCI_BASE_ADDRESS_SPACE_IO, 1 },
45 	{ PCI_BASE_ADDRESS_MEM_TYPE_32, MEM_TEXT_SIZE },
46 	{ 0, 0 },
47 	{ 0, 0 },
48 	{ 0, 0 },
49 	{ 0, 0 },
50 };
51 
52 struct swap_case_priv {
53 	enum swap_case_op op;
54 	char mem_text[MEM_TEXT_SIZE];
55 };
56 
57 static int sandbox_swap_case_get_devfn(struct udevice *dev)
58 {
59 	struct pci_child_platdata *plat = dev_get_parent_platdata(dev);
60 
61 	return plat->devfn;
62 }
63 
64 static int sandbox_swap_case_read_config(struct udevice *emul, uint offset,
65 					 ulong *valuep, enum pci_size_t size)
66 {
67 	struct swap_case_platdata *plat = dev_get_platdata(emul);
68 
69 	switch (offset) {
70 	case PCI_COMMAND:
71 		*valuep = plat->command;
72 		break;
73 	case PCI_HEADER_TYPE:
74 		*valuep = 0;
75 		break;
76 	case PCI_VENDOR_ID:
77 		*valuep = SANDBOX_PCI_VENDOR_ID;
78 		break;
79 	case PCI_DEVICE_ID:
80 		*valuep = SANDBOX_PCI_DEVICE_ID;
81 		break;
82 	case PCI_CLASS_DEVICE:
83 		if (size == PCI_SIZE_8) {
84 			*valuep = SANDBOX_PCI_CLASS_SUB_CODE;
85 		} else {
86 			*valuep = (SANDBOX_PCI_CLASS_CODE << 8) |
87 					SANDBOX_PCI_CLASS_SUB_CODE;
88 		}
89 		break;
90 	case PCI_CLASS_CODE:
91 		*valuep = SANDBOX_PCI_CLASS_CODE;
92 		break;
93 	case PCI_BASE_ADDRESS_0:
94 	case PCI_BASE_ADDRESS_1:
95 	case PCI_BASE_ADDRESS_2:
96 	case PCI_BASE_ADDRESS_3:
97 	case PCI_BASE_ADDRESS_4:
98 	case PCI_BASE_ADDRESS_5: {
99 		int barnum;
100 		u32 *bar, result;
101 
102 		barnum = offset_to_barnum(offset);
103 		bar = &plat->bar[barnum];
104 
105 		result = *bar;
106 		if (*bar == 0xffffffff) {
107 			if (barinfo[barnum].type) {
108 				result = (~(barinfo[barnum].size - 1) &
109 					PCI_BASE_ADDRESS_IO_MASK) |
110 					PCI_BASE_ADDRESS_SPACE_IO;
111 			} else {
112 				result = (~(barinfo[barnum].size - 1) &
113 					PCI_BASE_ADDRESS_MEM_MASK) |
114 					PCI_BASE_ADDRESS_MEM_TYPE_32;
115 			}
116 		}
117 		debug("r bar %d=%x\n", barnum, result);
118 		*valuep = result;
119 		break;
120 	}
121 	case PCI_CAPABILITY_LIST:
122 		*valuep = PCI_CAP_ID_PM_OFFSET;
123 		break;
124 	case PCI_CAP_ID_PM_OFFSET:
125 		*valuep = (PCI_CAP_ID_EXP_OFFSET << 8) | PCI_CAP_ID_PM;
126 		break;
127 	case PCI_CAP_ID_PM_OFFSET + PCI_CAP_LIST_NEXT:
128 		*valuep = PCI_CAP_ID_EXP_OFFSET;
129 		break;
130 	case PCI_CAP_ID_EXP_OFFSET:
131 		*valuep = (PCI_CAP_ID_MSIX_OFFSET << 8) | PCI_CAP_ID_EXP;
132 		break;
133 	case PCI_CAP_ID_EXP_OFFSET + PCI_CAP_LIST_NEXT:
134 		*valuep = PCI_CAP_ID_MSIX_OFFSET;
135 		break;
136 	case PCI_CAP_ID_MSIX_OFFSET:
137 		*valuep = PCI_CAP_ID_MSIX;
138 		break;
139 	case PCI_CAP_ID_MSIX_OFFSET + PCI_CAP_LIST_NEXT:
140 		*valuep = 0;
141 		break;
142 	case PCI_EXT_CAP_ID_ERR_OFFSET:
143 		*valuep = (PCI_EXT_CAP_ID_VC_OFFSET << 20) | PCI_EXT_CAP_ID_ERR;
144 		break;
145 	case PCI_EXT_CAP_ID_VC_OFFSET:
146 		*valuep = (PCI_EXT_CAP_ID_DSN_OFFSET << 20) | PCI_EXT_CAP_ID_VC;
147 		break;
148 	case PCI_EXT_CAP_ID_DSN_OFFSET:
149 		*valuep = PCI_EXT_CAP_ID_DSN;
150 		break;
151 	}
152 
153 	return 0;
154 }
155 
156 static int sandbox_swap_case_write_config(struct udevice *emul, uint offset,
157 					  ulong value, enum pci_size_t size)
158 {
159 	struct swap_case_platdata *plat = dev_get_platdata(emul);
160 
161 	switch (offset) {
162 	case PCI_COMMAND:
163 		plat->command = value;
164 		break;
165 	case PCI_BASE_ADDRESS_0:
166 	case PCI_BASE_ADDRESS_1: {
167 		int barnum;
168 		u32 *bar;
169 
170 		barnum = offset_to_barnum(offset);
171 		bar = &plat->bar[barnum];
172 
173 		debug("w bar %d=%lx\n", barnum, value);
174 		*bar = value;
175 		/* space indicator (bit#0) is read-only */
176 		*bar |= barinfo[barnum].type;
177 		break;
178 	}
179 	}
180 
181 	return 0;
182 }
183 
184 static int sandbox_swap_case_find_bar(struct udevice *emul, unsigned int addr,
185 				      int *barnump, unsigned int *offsetp)
186 {
187 	struct swap_case_platdata *plat = dev_get_platdata(emul);
188 	int barnum;
189 
190 	for (barnum = 0; barnum < ARRAY_SIZE(barinfo); barnum++) {
191 		unsigned int size = barinfo[barnum].size;
192 		u32 base = plat->bar[barnum] & ~PCI_BASE_ADDRESS_SPACE;
193 
194 		if (addr >= base && addr < base + size) {
195 			*barnump = barnum;
196 			*offsetp = addr - base;
197 			return 0;
198 		}
199 	}
200 	*barnump = -1;
201 
202 	return -ENOENT;
203 }
204 
205 static void sandbox_swap_case_do_op(enum swap_case_op op, char *str, int len)
206 {
207 	for (; len > 0; len--, str++) {
208 		switch (op) {
209 		case OP_TO_UPPER:
210 			*str = toupper(*str);
211 			break;
212 		case OP_TO_LOWER:
213 			*str = tolower(*str);
214 			break;
215 		case OP_SWAP:
216 			if (isupper(*str))
217 				*str = tolower(*str);
218 			else
219 				*str = toupper(*str);
220 			break;
221 		}
222 	}
223 }
224 
225 int sandbox_swap_case_read_io(struct udevice *dev, unsigned int addr,
226 			      ulong *valuep, enum pci_size_t size)
227 {
228 	struct swap_case_priv *priv = dev_get_priv(dev);
229 	unsigned int offset;
230 	int barnum;
231 	int ret;
232 
233 	ret = sandbox_swap_case_find_bar(dev, addr, &barnum, &offset);
234 	if (ret)
235 		return ret;
236 
237 	if (barnum == 0 && offset == 0)
238 		*valuep = (*valuep & ~0xff) | priv->op;
239 
240 	return 0;
241 }
242 
243 int sandbox_swap_case_write_io(struct udevice *dev, unsigned int addr,
244 			       ulong value, enum pci_size_t size)
245 {
246 	struct swap_case_priv *priv = dev_get_priv(dev);
247 	unsigned int offset;
248 	int barnum;
249 	int ret;
250 
251 	ret = sandbox_swap_case_find_bar(dev, addr, &barnum, &offset);
252 	if (ret)
253 		return ret;
254 	if (barnum == 0 && offset == 0)
255 		priv->op = value;
256 
257 	return 0;
258 }
259 
260 static int sandbox_swap_case_map_physmem(struct udevice *dev,
261 		phys_addr_t addr, unsigned long *lenp, void **ptrp)
262 {
263 	struct swap_case_priv *priv = dev_get_priv(dev);
264 	unsigned int offset, avail;
265 	int barnum;
266 	int ret;
267 
268 	ret = sandbox_swap_case_find_bar(dev, addr, &barnum, &offset);
269 	if (ret)
270 		return ret;
271 	if (barnum == 1) {
272 		*ptrp = priv->mem_text + offset;
273 		avail = barinfo[1].size - offset;
274 		if (avail > barinfo[1].size)
275 			*lenp = 0;
276 		else
277 			*lenp = min(*lenp, (ulong)avail);
278 
279 		return 0;
280 	}
281 
282 	return -ENOENT;
283 }
284 
285 static int sandbox_swap_case_unmap_physmem(struct udevice *dev,
286 					   const void *vaddr, unsigned long len)
287 {
288 	struct swap_case_priv *priv = dev_get_priv(dev);
289 
290 	sandbox_swap_case_do_op(priv->op, (void *)vaddr, len);
291 
292 	return 0;
293 }
294 
295 struct dm_pci_emul_ops sandbox_swap_case_emul_ops = {
296 	.get_devfn = sandbox_swap_case_get_devfn,
297 	.read_config = sandbox_swap_case_read_config,
298 	.write_config = sandbox_swap_case_write_config,
299 	.read_io = sandbox_swap_case_read_io,
300 	.write_io = sandbox_swap_case_write_io,
301 	.map_physmem = sandbox_swap_case_map_physmem,
302 	.unmap_physmem = sandbox_swap_case_unmap_physmem,
303 };
304 
305 static const struct udevice_id sandbox_swap_case_ids[] = {
306 	{ .compatible = "sandbox,swap-case" },
307 	{ }
308 };
309 
310 U_BOOT_DRIVER(sandbox_swap_case_emul) = {
311 	.name		= "sandbox_swap_case_emul",
312 	.id		= UCLASS_PCI_EMUL,
313 	.of_match	= sandbox_swap_case_ids,
314 	.ops		= &sandbox_swap_case_emul_ops,
315 	.priv_auto_alloc_size = sizeof(struct swap_case_priv),
316 	.platdata_auto_alloc_size = sizeof(struct swap_case_platdata),
317 };
318 
319 static struct pci_device_id sandbox_swap_case_supported[] = {
320 	{ PCI_VDEVICE(SANDBOX, SANDBOX_PCI_DEVICE_ID), SWAP_CASE_DRV_DATA },
321 	{},
322 };
323 
324 U_BOOT_PCI_DEVICE(sandbox_swap_case_emul, sandbox_swap_case_supported);
325