1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * Probing flash chips with QINFO records.
4 * (C) 2008 Korolev Alexey <akorolev@infradead.org>
5 * (C) 2008 Vasiliy Leonenko <vasiliy.leonenko@gmail.com>
6 */
7 #include <linux/module.h>
8 #include <linux/types.h>
9 #include <linux/kernel.h>
10 #include <linux/init.h>
11 #include <linux/errno.h>
12 #include <linux/slab.h>
13 #include <linux/interrupt.h>
14
15 #include <linux/mtd/xip.h>
16 #include <linux/mtd/map.h>
17 #include <linux/mtd/pfow.h>
18 #include <linux/mtd/qinfo.h>
19
20 static int lpddr_chip_setup(struct map_info *map, struct lpddr_private *lpddr);
21 struct mtd_info *lpddr_probe(struct map_info *map);
22 static struct lpddr_private *lpddr_probe_chip(struct map_info *map);
23 static int lpddr_pfow_present(struct map_info *map,
24 struct lpddr_private *lpddr);
25
26 static struct qinfo_query_info qinfo_array[] = {
27 /* General device info */
28 {0, 0, "DevSizeShift", "Device size 2^n bytes"},
29 {0, 3, "BufSizeShift", "Program buffer size 2^n bytes"},
30 /* Erase block information */
31 {1, 1, "TotalBlocksNum", "Total number of blocks"},
32 {1, 2, "UniformBlockSizeShift", "Uniform block size 2^n bytes"},
33 /* Partition information */
34 {2, 1, "HWPartsNum", "Number of hardware partitions"},
35 /* Optional features */
36 {5, 1, "SuspEraseSupp", "Suspend erase supported"},
37 /* Operation typical time */
38 {10, 0, "SingleWordProgTime", "Single word program 2^n u-sec"},
39 {10, 1, "ProgBufferTime", "Program buffer write 2^n u-sec"},
40 {10, 2, "BlockEraseTime", "Block erase 2^n m-sec"},
41 {10, 3, "FullChipEraseTime", "Full chip erase 2^n m-sec"},
42 };
43
lpddr_get_qinforec_pos(struct map_info * map,char * id_str)44 static long lpddr_get_qinforec_pos(struct map_info *map, char *id_str)
45 {
46 int qinfo_lines = ARRAY_SIZE(qinfo_array);
47 int i;
48 int bankwidth = map_bankwidth(map) * 8;
49 int major, minor;
50
51 for (i = 0; i < qinfo_lines; i++) {
52 if (strcmp(id_str, qinfo_array[i].id_str) == 0) {
53 major = qinfo_array[i].major & ((1 << bankwidth) - 1);
54 minor = qinfo_array[i].minor & ((1 << bankwidth) - 1);
55 return minor | (major << bankwidth);
56 }
57 }
58 printk(KERN_ERR"%s qinfo id string is wrong! \n", map->name);
59 BUG();
60 return -1;
61 }
62
lpddr_info_query(struct map_info * map,char * id_str)63 static uint16_t lpddr_info_query(struct map_info *map, char *id_str)
64 {
65 unsigned int dsr, val;
66 int bits_per_chip = map_bankwidth(map) * 8;
67 unsigned long adr = lpddr_get_qinforec_pos(map, id_str);
68 int attempts = 20;
69
70 /* Write a request for the PFOW record */
71 map_write(map, CMD(LPDDR_INFO_QUERY),
72 map->pfow_base + PFOW_COMMAND_CODE);
73 map_write(map, CMD(adr & ((1 << bits_per_chip) - 1)),
74 map->pfow_base + PFOW_COMMAND_ADDRESS_L);
75 map_write(map, CMD(adr >> bits_per_chip),
76 map->pfow_base + PFOW_COMMAND_ADDRESS_H);
77 map_write(map, CMD(LPDDR_START_EXECUTION),
78 map->pfow_base + PFOW_COMMAND_EXECUTE);
79
80 while ((attempts--) > 0) {
81 dsr = CMDVAL(map_read(map, map->pfow_base + PFOW_DSR));
82 if (dsr & DSR_READY_STATUS)
83 break;
84 udelay(10);
85 }
86
87 val = CMDVAL(map_read(map, map->pfow_base + PFOW_COMMAND_DATA));
88 return val;
89 }
90
lpddr_pfow_present(struct map_info * map,struct lpddr_private * lpddr)91 static int lpddr_pfow_present(struct map_info *map, struct lpddr_private *lpddr)
92 {
93 map_word pfow_val[4];
94
95 /* Check identification string */
96 pfow_val[0] = map_read(map, map->pfow_base + PFOW_QUERY_STRING_P);
97 pfow_val[1] = map_read(map, map->pfow_base + PFOW_QUERY_STRING_F);
98 pfow_val[2] = map_read(map, map->pfow_base + PFOW_QUERY_STRING_O);
99 pfow_val[3] = map_read(map, map->pfow_base + PFOW_QUERY_STRING_W);
100
101 if (!map_word_equal(map, CMD('P'), pfow_val[0]))
102 goto out;
103
104 if (!map_word_equal(map, CMD('F'), pfow_val[1]))
105 goto out;
106
107 if (!map_word_equal(map, CMD('O'), pfow_val[2]))
108 goto out;
109
110 if (!map_word_equal(map, CMD('W'), pfow_val[3]))
111 goto out;
112
113 return 1; /* "PFOW" is found */
114 out:
115 printk(KERN_WARNING"%s: PFOW string at 0x%lx is not found \n",
116 map->name, map->pfow_base);
117 return 0;
118 }
119
lpddr_chip_setup(struct map_info * map,struct lpddr_private * lpddr)120 static int lpddr_chip_setup(struct map_info *map, struct lpddr_private *lpddr)
121 {
122
123 lpddr->qinfo = kzalloc(sizeof(struct qinfo_chip), GFP_KERNEL);
124 if (!lpddr->qinfo)
125 return 0;
126
127 /* Get the ManuID */
128 lpddr->ManufactId = CMDVAL(map_read(map, map->pfow_base + PFOW_MANUFACTURER_ID));
129 /* Get the DeviceID */
130 lpddr->DevId = CMDVAL(map_read(map, map->pfow_base + PFOW_DEVICE_ID));
131 /* read parameters from chip qinfo table */
132 lpddr->qinfo->DevSizeShift = lpddr_info_query(map, "DevSizeShift");
133 lpddr->qinfo->TotalBlocksNum = lpddr_info_query(map, "TotalBlocksNum");
134 lpddr->qinfo->BufSizeShift = lpddr_info_query(map, "BufSizeShift");
135 lpddr->qinfo->HWPartsNum = lpddr_info_query(map, "HWPartsNum");
136 lpddr->qinfo->UniformBlockSizeShift =
137 lpddr_info_query(map, "UniformBlockSizeShift");
138 lpddr->qinfo->SuspEraseSupp = lpddr_info_query(map, "SuspEraseSupp");
139 lpddr->qinfo->SingleWordProgTime =
140 lpddr_info_query(map, "SingleWordProgTime");
141 lpddr->qinfo->ProgBufferTime = lpddr_info_query(map, "ProgBufferTime");
142 lpddr->qinfo->BlockEraseTime = lpddr_info_query(map, "BlockEraseTime");
143 return 1;
144 }
lpddr_probe_chip(struct map_info * map)145 static struct lpddr_private *lpddr_probe_chip(struct map_info *map)
146 {
147 struct lpddr_private lpddr;
148 struct lpddr_private *retlpddr;
149 int numvirtchips;
150
151
152 if ((map->pfow_base + 0x1000) >= map->size) {
153 printk(KERN_NOTICE"%s Probe at base (0x%08lx) past the end of"
154 "the map(0x%08lx)\n", map->name,
155 (unsigned long)map->pfow_base, map->size - 1);
156 return NULL;
157 }
158 memset(&lpddr, 0, sizeof(struct lpddr_private));
159 if (!lpddr_pfow_present(map, &lpddr))
160 return NULL;
161
162 if (!lpddr_chip_setup(map, &lpddr))
163 return NULL;
164
165 /* Ok so we found a chip */
166 lpddr.chipshift = lpddr.qinfo->DevSizeShift;
167 lpddr.numchips = 1;
168
169 numvirtchips = lpddr.numchips * lpddr.qinfo->HWPartsNum;
170 retlpddr = kzalloc(struct_size(retlpddr, chips, numvirtchips),
171 GFP_KERNEL);
172 if (!retlpddr)
173 return NULL;
174
175 memcpy(retlpddr, &lpddr, sizeof(struct lpddr_private));
176
177 retlpddr->numchips = numvirtchips;
178 retlpddr->chipshift = retlpddr->qinfo->DevSizeShift -
179 __ffs(retlpddr->qinfo->HWPartsNum);
180
181 return retlpddr;
182 }
183
lpddr_probe(struct map_info * map)184 struct mtd_info *lpddr_probe(struct map_info *map)
185 {
186 struct mtd_info *mtd = NULL;
187 struct lpddr_private *lpddr;
188
189 /* First probe the map to see if we havecan open PFOW here */
190 lpddr = lpddr_probe_chip(map);
191 if (!lpddr)
192 return NULL;
193
194 map->fldrv_priv = lpddr;
195 mtd = lpddr_cmdset(map);
196 if (mtd) {
197 if (mtd->size > map->size) {
198 printk(KERN_WARNING "Reducing visibility of %ldKiB chip"
199 "to %ldKiB\n", (unsigned long)mtd->size >> 10,
200 (unsigned long)map->size >> 10);
201 mtd->size = map->size;
202 }
203 return mtd;
204 }
205
206 kfree(lpddr->qinfo);
207 kfree(lpddr);
208 map->fldrv_priv = NULL;
209 return NULL;
210 }
211
212 static struct mtd_chip_driver lpddr_chipdrv = {
213 .probe = lpddr_probe,
214 .name = "qinfo_probe",
215 .module = THIS_MODULE
216 };
217
lpddr_probe_init(void)218 static int __init lpddr_probe_init(void)
219 {
220 register_mtd_chip_driver(&lpddr_chipdrv);
221 return 0;
222 }
223
lpddr_probe_exit(void)224 static void __exit lpddr_probe_exit(void)
225 {
226 unregister_mtd_chip_driver(&lpddr_chipdrv);
227 }
228
229 module_init(lpddr_probe_init);
230 module_exit(lpddr_probe_exit);
231
232 MODULE_LICENSE("GPL");
233 MODULE_AUTHOR("Vasiliy Leonenko <vasiliy.leonenko@gmail.com>");
234 MODULE_DESCRIPTION("Driver to probe qinfo flash chips");
235
236