xref: /openbmc/linux/drivers/mcb/mcb-parse.c (revision 98a52692)
1 // SPDX-License-Identifier: GPL-2.0-only
2 #include <linux/types.h>
3 #include <linux/ioport.h>
4 #include <linux/slab.h>
5 #include <linux/export.h>
6 #include <linux/io.h>
7 #include <linux/mcb.h>
8 
9 #include "mcb-internal.h"
10 
11 struct mcb_parse_priv {
12 	phys_addr_t mapbase;
13 	void __iomem *base;
14 };
15 
16 #define for_each_chameleon_cell(dtype, p)	\
17 	for ((dtype) = get_next_dtype((p));	\
18 	     (dtype) != CHAMELEON_DTYPE_END;	\
19 	     (dtype) = get_next_dtype((p)))
20 
21 static inline uint32_t get_next_dtype(void __iomem *p)
22 {
23 	uint32_t dtype;
24 
25 	dtype = readl(p);
26 	return dtype >> 28;
27 }
28 
29 static int chameleon_parse_bdd(struct mcb_bus *bus,
30 			struct chameleon_bar *cb,
31 			void __iomem *base)
32 {
33 	return 0;
34 }
35 
36 static int chameleon_parse_gdd(struct mcb_bus *bus,
37 			struct chameleon_bar *cb,
38 			void __iomem *base, int bar_count)
39 {
40 	struct chameleon_gdd __iomem *gdd =
41 		(struct chameleon_gdd __iomem *) base;
42 	struct mcb_device *mdev;
43 	u32 dev_mapbase;
44 	u32 offset;
45 	u32 size;
46 	int ret;
47 	__le32 reg1;
48 	__le32 reg2;
49 
50 	mdev = mcb_alloc_dev(bus);
51 	if (!mdev)
52 		return -ENOMEM;
53 
54 	reg1 = readl(&gdd->reg1);
55 	reg2 = readl(&gdd->reg2);
56 	offset = readl(&gdd->offset);
57 	size = readl(&gdd->size);
58 
59 	mdev->id = GDD_DEV(reg1);
60 	mdev->rev = GDD_REV(reg1);
61 	mdev->var = GDD_VAR(reg1);
62 	mdev->bar = GDD_BAR(reg2);
63 	mdev->group = GDD_GRP(reg2);
64 	mdev->inst = GDD_INS(reg2);
65 
66 	/*
67 	 * If the BAR is missing, dev_mapbase is zero, or if the
68 	 * device is IO mapped we just print a warning and go on with the
69 	 * next device, instead of completely stop the gdd parser
70 	 */
71 	if (mdev->bar > bar_count - 1) {
72 		pr_info("No BAR for 16z%03d\n", mdev->id);
73 		ret = 0;
74 		goto err;
75 	}
76 
77 	dev_mapbase = cb[mdev->bar].addr;
78 	if (!dev_mapbase) {
79 		pr_info("BAR not assigned for 16z%03d\n", mdev->id);
80 		ret = 0;
81 		goto err;
82 	}
83 
84 	if (dev_mapbase & 0x01) {
85 		pr_info("IO mapped Device (16z%03d) not yet supported\n",
86 			mdev->id);
87 		ret = 0;
88 		goto err;
89 	}
90 
91 	pr_debug("Found a 16z%03d\n", mdev->id);
92 
93 	mdev->irq.start = GDD_IRQ(reg1);
94 	mdev->irq.end = GDD_IRQ(reg1);
95 	mdev->irq.flags = IORESOURCE_IRQ;
96 
97 	mdev->mem.start = dev_mapbase + offset;
98 
99 	mdev->mem.end = mdev->mem.start + size - 1;
100 	mdev->mem.flags = IORESOURCE_MEM;
101 
102 	ret = mcb_device_register(bus, mdev);
103 	if (ret < 0)
104 		goto err;
105 
106 	return 0;
107 
108 err:
109 	put_device(&mdev->dev);
110 
111 	return ret;
112 }
113 
114 static void chameleon_parse_bar(void __iomem *base,
115 				struct chameleon_bar *cb, int bar_count)
116 {
117 	char __iomem *p = base;
118 	int i;
119 
120 	/* skip reg1 */
121 	p += sizeof(__le32);
122 
123 	for (i = 0; i < bar_count; i++) {
124 		cb[i].addr = readl(p);
125 		cb[i].size = readl(p + 4);
126 
127 		p += sizeof(struct chameleon_bar);
128 	}
129 }
130 
131 static int chameleon_get_bar(void __iomem **base, phys_addr_t mapbase,
132 			     struct chameleon_bar **cb)
133 {
134 	struct chameleon_bar *c;
135 	int bar_count;
136 	__le32 reg;
137 	u32 dtype;
138 
139 	/*
140 	 * For those devices which are not connected
141 	 * to the PCI Bus (e.g. LPC) there is a bar
142 	 * descriptor located directly after the
143 	 * chameleon header. This header is comparable
144 	 * to a PCI header.
145 	 */
146 	dtype = get_next_dtype(*base);
147 	if (dtype == CHAMELEON_DTYPE_BAR) {
148 		reg = readl(*base);
149 
150 		bar_count = BAR_CNT(reg);
151 		if (bar_count <= 0 || bar_count > CHAMELEON_BAR_MAX)
152 			return -ENODEV;
153 
154 		c = kcalloc(bar_count, sizeof(struct chameleon_bar),
155 			    GFP_KERNEL);
156 		if (!c)
157 			return -ENOMEM;
158 
159 		chameleon_parse_bar(*base, c, bar_count);
160 		*base += BAR_DESC_SIZE(bar_count);
161 	} else {
162 		c = kzalloc(sizeof(struct chameleon_bar), GFP_KERNEL);
163 		if (!c)
164 			return -ENOMEM;
165 
166 		bar_count = 1;
167 		c->addr = mapbase;
168 	}
169 
170 	*cb = c;
171 
172 	return bar_count;
173 }
174 
175 int chameleon_parse_cells(struct mcb_bus *bus, phys_addr_t mapbase,
176 			void __iomem *base)
177 {
178 	struct chameleon_fpga_header *header;
179 	struct chameleon_bar *cb;
180 	void __iomem *p = base;
181 	int num_cells = 0;
182 	uint32_t dtype;
183 	int bar_count;
184 	int ret;
185 	u32 hsize;
186 	u32 table_size;
187 
188 	hsize = sizeof(struct chameleon_fpga_header);
189 
190 	header = kzalloc(hsize, GFP_KERNEL);
191 	if (!header)
192 		return -ENOMEM;
193 
194 	/* Extract header information */
195 	memcpy_fromio(header, p, hsize);
196 	/* We only support chameleon v2 at the moment */
197 	header->magic = le16_to_cpu(header->magic);
198 	if (header->magic != CHAMELEONV2_MAGIC) {
199 		pr_err("Unsupported chameleon version 0x%x\n",
200 				header->magic);
201 		ret = -ENODEV;
202 		goto free_header;
203 	}
204 	p += hsize;
205 
206 	bus->revision = header->revision;
207 	bus->model = header->model;
208 	bus->minor = header->minor;
209 	snprintf(bus->name, CHAMELEON_FILENAME_LEN + 1, "%s",
210 		 header->filename);
211 
212 	bar_count = chameleon_get_bar(&p, mapbase, &cb);
213 	if (bar_count < 0) {
214 		ret = bar_count;
215 		goto free_header;
216 	}
217 
218 	for_each_chameleon_cell(dtype, p) {
219 		switch (dtype) {
220 		case CHAMELEON_DTYPE_GENERAL:
221 			ret = chameleon_parse_gdd(bus, cb, p, bar_count);
222 			if (ret < 0)
223 				goto free_bar;
224 			p += sizeof(struct chameleon_gdd);
225 			break;
226 		case CHAMELEON_DTYPE_BRIDGE:
227 			chameleon_parse_bdd(bus, cb, p);
228 			p += sizeof(struct chameleon_bdd);
229 			break;
230 		case CHAMELEON_DTYPE_END:
231 			break;
232 		default:
233 			pr_err("Invalid chameleon descriptor type 0x%x\n",
234 				dtype);
235 			ret = -EINVAL;
236 			goto free_bar;
237 		}
238 		num_cells++;
239 	}
240 
241 	if (num_cells == 0) {
242 		ret = -EINVAL;
243 		goto free_bar;
244 	}
245 
246 	table_size = p - base;
247 	pr_debug("%d cell(s) found. Chameleon table size: 0x%04x bytes\n", num_cells, table_size);
248 	kfree(cb);
249 	kfree(header);
250 	return table_size;
251 
252 free_bar:
253 	kfree(cb);
254 free_header:
255 	kfree(header);
256 
257 	return ret;
258 }
259 EXPORT_SYMBOL_NS_GPL(chameleon_parse_cells, MCB);
260