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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 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 | #include <linux/kernel.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/delay.h>
#include <linux/mtd/mtd.h>
#include <linux/platform_device.h>
#include <linux/bcma/bcma.h>
#include "bcm47xxsflash.h"
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Serial flash driver for BCMA bus");
static const char * const probes[] = { "bcm47xxpart", NULL };
/**************************************************
* Various helpers
**************************************************/
static void bcm47xxsflash_cmd(struct bcm47xxsflash *b47s, u32 opcode)
{
int i;
b47s->cc_write(b47s, BCMA_CC_FLASHCTL, BCMA_CC_FLASHCTL_START | opcode);
for (i = 0; i < 1000; i++) {
if (!(b47s->cc_read(b47s, BCMA_CC_FLASHCTL) &
BCMA_CC_FLASHCTL_BUSY))
return;
cpu_relax();
}
pr_err("Control command failed (timeout)!\n");
}
static int bcm47xxsflash_poll(struct bcm47xxsflash *b47s, int timeout)
{
unsigned long deadline = jiffies + timeout;
do {
switch (b47s->type) {
case BCM47XXSFLASH_TYPE_ST:
bcm47xxsflash_cmd(b47s, OPCODE_ST_RDSR);
if (!(b47s->cc_read(b47s, BCMA_CC_FLASHDATA) &
SR_ST_WIP))
return 0;
break;
case BCM47XXSFLASH_TYPE_ATMEL:
bcm47xxsflash_cmd(b47s, OPCODE_AT_STATUS);
if (b47s->cc_read(b47s, BCMA_CC_FLASHDATA) &
SR_AT_READY)
return 0;
break;
}
cpu_relax();
udelay(1);
} while (!time_after_eq(jiffies, deadline));
pr_err("Timeout waiting for flash to be ready!\n");
return -EBUSY;
}
/**************************************************
* MTD ops
**************************************************/
static int bcm47xxsflash_erase(struct mtd_info *mtd, struct erase_info *erase)
{
struct bcm47xxsflash *b47s = mtd->priv;
int err;
switch (b47s->type) {
case BCM47XXSFLASH_TYPE_ST:
bcm47xxsflash_cmd(b47s, OPCODE_ST_WREN);
b47s->cc_write(b47s, BCMA_CC_FLASHADDR, erase->addr);
/* Newer flashes have "sub-sectors" which can be erased
* independently with a new command: ST_SSE. The ST_SE command
* erases 64KB just as before.
*/
if (b47s->blocksize < (64 * 1024))
bcm47xxsflash_cmd(b47s, OPCODE_ST_SSE);
else
bcm47xxsflash_cmd(b47s, OPCODE_ST_SE);
break;
case BCM47XXSFLASH_TYPE_ATMEL:
b47s->cc_write(b47s, BCMA_CC_FLASHADDR, erase->addr << 1);
bcm47xxsflash_cmd(b47s, OPCODE_AT_PAGE_ERASE);
break;
}
err = bcm47xxsflash_poll(b47s, HZ);
if (err)
erase->state = MTD_ERASE_FAILED;
else
erase->state = MTD_ERASE_DONE;
if (erase->callback)
erase->callback(erase);
return err;
}
static int bcm47xxsflash_read(struct mtd_info *mtd, loff_t from, size_t len,
size_t *retlen, u_char *buf)
{
struct bcm47xxsflash *b47s = mtd->priv;
/* Check address range */
if ((from + len) > mtd->size)
return -EINVAL;
memcpy_fromio(buf, (void __iomem *)KSEG0ADDR(b47s->window + from),
len);
*retlen = len;
return len;
}
static int bcm47xxsflash_write_st(struct mtd_info *mtd, u32 offset, size_t len,
const u_char *buf)
{
struct bcm47xxsflash *b47s = mtd->priv;
int written = 0;
/* Enable writes */
bcm47xxsflash_cmd(b47s, OPCODE_ST_WREN);
/* Write first byte */
b47s->cc_write(b47s, BCMA_CC_FLASHADDR, offset);
b47s->cc_write(b47s, BCMA_CC_FLASHDATA, *buf++);
/* Program page */
if (b47s->bcma_cc->core->id.rev < 20) {
bcm47xxsflash_cmd(b47s, OPCODE_ST_PP);
return 1; /* 1B written */
}
/* Program page and set CSA (on newer chips we can continue writing) */
bcm47xxsflash_cmd(b47s, OPCODE_ST_CSA | OPCODE_ST_PP);
offset++;
len--;
written++;
while (len > 0) {
/* Page boundary, another function call is needed */
if ((offset & 0xFF) == 0)
break;
bcm47xxsflash_cmd(b47s, OPCODE_ST_CSA | *buf++);
offset++;
len--;
written++;
}
/* All done, drop CSA & poll */
b47s->cc_write(b47s, BCMA_CC_FLASHCTL, 0);
udelay(1);
if (bcm47xxsflash_poll(b47s, HZ / 10))
pr_err("Flash rejected dropping CSA\n");
return written;
}
static int bcm47xxsflash_write_at(struct mtd_info *mtd, u32 offset, size_t len,
const u_char *buf)
{
struct bcm47xxsflash *b47s = mtd->priv;
u32 mask = b47s->blocksize - 1;
u32 page = (offset & ~mask) << 1;
u32 byte = offset & mask;
int written = 0;
/* If we don't overwrite whole page, read it to the buffer first */
if (byte || (len < b47s->blocksize)) {
int err;
b47s->cc_write(b47s, BCMA_CC_FLASHADDR, page);
bcm47xxsflash_cmd(b47s, OPCODE_AT_BUF1_LOAD);
/* 250 us for AT45DB321B */
err = bcm47xxsflash_poll(b47s, HZ / 1000);
if (err) {
pr_err("Timeout reading page 0x%X info buffer\n", page);
return err;
}
}
/* Change buffer content with our data */
while (len > 0) {
/* Page boundary, another function call is needed */
if (byte == b47s->blocksize)
break;
b47s->cc_write(b47s, BCMA_CC_FLASHADDR, byte++);
b47s->cc_write(b47s, BCMA_CC_FLASHDATA, *buf++);
bcm47xxsflash_cmd(b47s, OPCODE_AT_BUF1_WRITE);
len--;
written++;
}
/* Program page with the buffer content */
b47s->cc_write(b47s, BCMA_CC_FLASHADDR, page);
bcm47xxsflash_cmd(b47s, OPCODE_AT_BUF1_PROGRAM);
return written;
}
static int bcm47xxsflash_write(struct mtd_info *mtd, loff_t to, size_t len,
size_t *retlen, const u_char *buf)
{
struct bcm47xxsflash *b47s = mtd->priv;
int written;
/* Writing functions can return without writing all passed data, for
* example when the hardware is too old or when we git page boundary.
*/
while (len > 0) {
switch (b47s->type) {
case BCM47XXSFLASH_TYPE_ST:
written = bcm47xxsflash_write_st(mtd, to, len, buf);
break;
case BCM47XXSFLASH_TYPE_ATMEL:
written = bcm47xxsflash_write_at(mtd, to, len, buf);
break;
default:
BUG_ON(1);
}
if (written < 0) {
pr_err("Error writing at offset 0x%llX\n", to);
return written;
}
to += (loff_t)written;
len -= written;
*retlen += written;
buf += written;
}
return 0;
}
static void bcm47xxsflash_fill_mtd(struct bcm47xxsflash *b47s,
struct device *dev)
{
struct mtd_info *mtd = &b47s->mtd;
mtd->priv = b47s;
mtd->dev.parent = dev;
mtd->name = "bcm47xxsflash";
mtd->type = MTD_NORFLASH;
mtd->flags = MTD_CAP_NORFLASH;
mtd->size = b47s->size;
mtd->erasesize = b47s->blocksize;
mtd->writesize = 1;
mtd->writebufsize = 1;
mtd->_erase = bcm47xxsflash_erase;
mtd->_read = bcm47xxsflash_read;
mtd->_write = bcm47xxsflash_write;
}
/**************************************************
* BCMA
**************************************************/
static int bcm47xxsflash_bcma_cc_read(struct bcm47xxsflash *b47s, u16 offset)
{
return bcma_cc_read32(b47s->bcma_cc, offset);
}
static void bcm47xxsflash_bcma_cc_write(struct bcm47xxsflash *b47s, u16 offset,
u32 value)
{
bcma_cc_write32(b47s->bcma_cc, offset, value);
}
static int bcm47xxsflash_bcma_probe(struct platform_device *pdev)
{
struct bcma_sflash *sflash = dev_get_platdata(&pdev->dev);
struct bcm47xxsflash *b47s;
int err;
b47s = devm_kzalloc(&pdev->dev, sizeof(*b47s), GFP_KERNEL);
if (!b47s)
return -ENOMEM;
sflash->priv = b47s;
b47s->bcma_cc = container_of(sflash, struct bcma_drv_cc, sflash);
b47s->cc_read = bcm47xxsflash_bcma_cc_read;
b47s->cc_write = bcm47xxsflash_bcma_cc_write;
switch (b47s->bcma_cc->capabilities & BCMA_CC_CAP_FLASHT) {
case BCMA_CC_FLASHT_STSER:
b47s->type = BCM47XXSFLASH_TYPE_ST;
break;
case BCMA_CC_FLASHT_ATSER:
b47s->type = BCM47XXSFLASH_TYPE_ATMEL;
break;
}
b47s->window = sflash->window;
b47s->blocksize = sflash->blocksize;
b47s->numblocks = sflash->numblocks;
b47s->size = sflash->size;
bcm47xxsflash_fill_mtd(b47s, &pdev->dev);
err = mtd_device_parse_register(&b47s->mtd, probes, NULL, NULL, 0);
if (err) {
pr_err("Failed to register MTD device: %d\n", err);
return err;
}
if (bcm47xxsflash_poll(b47s, HZ / 10))
pr_warn("Serial flash busy\n");
return 0;
}
static int bcm47xxsflash_bcma_remove(struct platform_device *pdev)
{
struct bcma_sflash *sflash = dev_get_platdata(&pdev->dev);
struct bcm47xxsflash *b47s = sflash->priv;
mtd_device_unregister(&b47s->mtd);
return 0;
}
static struct platform_driver bcma_sflash_driver = {
.probe = bcm47xxsflash_bcma_probe,
.remove = bcm47xxsflash_bcma_remove,
.driver = {
.name = "bcma_sflash",
},
};
/**************************************************
* Init
**************************************************/
module_platform_driver(bcma_sflash_driver);
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