1/*
2 * Sonics Silicon Backplane
3 * ChipCommon serial flash interface
4 *
5 * Licensed under the GNU/GPL. See COPYING for details.
6 */
7
8#include <linux/ssb/ssb.h>
9
10#include "ssb_private.h"
11
12static struct resource ssb_sflash_resource = {
13	.name	= "ssb_sflash",
14	.start	= SSB_FLASH2,
15	.end	= 0,
16	.flags  = IORESOURCE_MEM | IORESOURCE_READONLY,
17};
18
19struct platform_device ssb_sflash_dev = {
20	.name		= "ssb_sflash",
21	.resource	= &ssb_sflash_resource,
22	.num_resources	= 1,
23};
24
25struct ssb_sflash_tbl_e {
26	char *name;
27	u32 id;
28	u32 blocksize;
29	u16 numblocks;
30};
31
32static const struct ssb_sflash_tbl_e ssb_sflash_st_tbl[] = {
33	{ "M25P20", 0x11, 0x10000, 4, },
34	{ "M25P40", 0x12, 0x10000, 8, },
35
36	{ "M25P16", 0x14, 0x10000, 32, },
37	{ "M25P32", 0x15, 0x10000, 64, },
38	{ "M25P64", 0x16, 0x10000, 128, },
39	{ "M25FL128", 0x17, 0x10000, 256, },
40	{ NULL },
41};
42
43static const struct ssb_sflash_tbl_e ssb_sflash_sst_tbl[] = {
44	{ "SST25WF512", 1, 0x1000, 16, },
45	{ "SST25VF512", 0x48, 0x1000, 16, },
46	{ "SST25WF010", 2, 0x1000, 32, },
47	{ "SST25VF010", 0x49, 0x1000, 32, },
48	{ "SST25WF020", 3, 0x1000, 64, },
49	{ "SST25VF020", 0x43, 0x1000, 64, },
50	{ "SST25WF040", 4, 0x1000, 128, },
51	{ "SST25VF040", 0x44, 0x1000, 128, },
52	{ "SST25VF040B", 0x8d, 0x1000, 128, },
53	{ "SST25WF080", 5, 0x1000, 256, },
54	{ "SST25VF080B", 0x8e, 0x1000, 256, },
55	{ "SST25VF016", 0x41, 0x1000, 512, },
56	{ "SST25VF032", 0x4a, 0x1000, 1024, },
57	{ "SST25VF064", 0x4b, 0x1000, 2048, },
58	{ NULL },
59};
60
61static const struct ssb_sflash_tbl_e ssb_sflash_at_tbl[] = {
62	{ "AT45DB011", 0xc, 256, 512, },
63	{ "AT45DB021", 0x14, 256, 1024, },
64	{ "AT45DB041", 0x1c, 256, 2048, },
65	{ "AT45DB081", 0x24, 256, 4096, },
66	{ "AT45DB161", 0x2c, 512, 4096, },
67	{ "AT45DB321", 0x34, 512, 8192, },
68	{ "AT45DB642", 0x3c, 1024, 8192, },
69	{ NULL },
70};
71
72static void ssb_sflash_cmd(struct ssb_chipcommon *cc, u32 opcode)
73{
74	int i;
75	chipco_write32(cc, SSB_CHIPCO_FLASHCTL,
76		       SSB_CHIPCO_FLASHCTL_START | opcode);
77	for (i = 0; i < 1000; i++) {
78		if (!(chipco_read32(cc, SSB_CHIPCO_FLASHCTL) &
79		      SSB_CHIPCO_FLASHCTL_BUSY))
80			return;
81		cpu_relax();
82	}
83	pr_err("SFLASH control command failed (timeout)!\n");
84}
85
86/* Initialize serial flash access */
87int ssb_sflash_init(struct ssb_chipcommon *cc)
88{
89	struct ssb_sflash *sflash = &cc->dev->bus->mipscore.sflash;
90	const struct ssb_sflash_tbl_e *e;
91	u32 id, id2;
92
93	switch (cc->capabilities & SSB_CHIPCO_CAP_FLASHT) {
94	case SSB_CHIPCO_FLASHT_STSER:
95		ssb_sflash_cmd(cc, SSB_CHIPCO_FLASHCTL_ST_DP);
96
97		chipco_write32(cc, SSB_CHIPCO_FLASHADDR, 0);
98		ssb_sflash_cmd(cc, SSB_CHIPCO_FLASHCTL_ST_RES);
99		id = chipco_read32(cc, SSB_CHIPCO_FLASHDATA);
100
101		chipco_write32(cc, SSB_CHIPCO_FLASHADDR, 1);
102		ssb_sflash_cmd(cc, SSB_CHIPCO_FLASHCTL_ST_RES);
103		id2 = chipco_read32(cc, SSB_CHIPCO_FLASHDATA);
104
105		switch (id) {
106		case 0xbf:
107			for (e = ssb_sflash_sst_tbl; e->name; e++) {
108				if (e->id == id2)
109					break;
110			}
111			break;
112		case 0x13:
113			return -ENOTSUPP;
114		default:
115			for (e = ssb_sflash_st_tbl; e->name; e++) {
116				if (e->id == id)
117					break;
118			}
119			break;
120		}
121		if (!e->name) {
122			pr_err("Unsupported ST serial flash (id: 0x%X, id2: 0x%X)\n",
123			       id, id2);
124			return -ENOTSUPP;
125		}
126
127		break;
128	case SSB_CHIPCO_FLASHT_ATSER:
129		ssb_sflash_cmd(cc, SSB_CHIPCO_FLASHCTL_AT_STATUS);
130		id = chipco_read32(cc, SSB_CHIPCO_FLASHDATA) & 0x3c;
131
132		for (e = ssb_sflash_at_tbl; e->name; e++) {
133			if (e->id == id)
134				break;
135		}
136		if (!e->name) {
137			pr_err("Unsupported Atmel serial flash (id: 0x%X)\n",
138			       id);
139			return -ENOTSUPP;
140		}
141
142		break;
143	default:
144		pr_err("Unsupported flash type\n");
145		return -ENOTSUPP;
146	}
147
148	sflash->window = SSB_FLASH2;
149	sflash->blocksize = e->blocksize;
150	sflash->numblocks = e->numblocks;
151	sflash->size = sflash->blocksize * sflash->numblocks;
152	sflash->present = true;
153
154	pr_info("Found %s serial flash (size: %dKiB, blocksize: 0x%X, blocks: %d)\n",
155		e->name, sflash->size / 1024, e->blocksize, e->numblocks);
156
157	/* Prepare platform device, but don't register it yet. It's too early,
158	 * malloc (required by device_private_init) is not available yet. */
159	ssb_sflash_dev.resource[0].end = ssb_sflash_dev.resource[0].start +
160					 sflash->size;
161	ssb_sflash_dev.dev.platform_data = sflash;
162
163	return 0;
164}
165