return crc;
}
+/* Parse the Extended Parameter Page. */
+static int nand_flash_detect_ext_param_page(struct mtd_info *mtd,
+ struct nand_chip *chip, struct nand_onfi_params *p)
+{
+ struct onfi_ext_param_page *ep;
+ struct onfi_ext_section *s;
+ struct onfi_ext_ecc_info *ecc;
+ uint8_t *cursor;
+ int ret = -EINVAL;
+ int len;
+ int i;
+
+ len = le16_to_cpu(p->ext_param_page_length) * 16;
+ ep = kmalloc(len, GFP_KERNEL);
+ if (!ep) {
+ ret = -ENOMEM;
+ goto ext_out;
+ }
+
+ /* Send our own NAND_CMD_PARAM. */
+ chip->cmdfunc(mtd, NAND_CMD_PARAM, 0, -1);
+
+ /* Use the Change Read Column command to skip the ONFI param pages. */
+ chip->cmdfunc(mtd, NAND_CMD_RNDOUT,
+ sizeof(*p) * p->num_of_param_pages , -1);
+
+ /* Read out the Extended Parameter Page. */
+ chip->read_buf(mtd, (uint8_t *)ep, len);
+ if ((onfi_crc16(ONFI_CRC_BASE, ((uint8_t *)ep) + 2, len - 2)
+ != le16_to_cpu(ep->crc))) {
+ pr_debug("fail in the CRC.\n");
+ goto ext_out;
+ }
+
+ /*
+ * Check the signature.
+ * Do not strictly follow the ONFI spec, maybe changed in future.
+ */
+ if (strncmp(ep->sig, "EPPS", 4)) {
+ pr_debug("The signature is invalid.\n");
+ goto ext_out;
+ }
+
+ /* find the ECC section. */
+ cursor = (uint8_t *)(ep + 1);
+ for (i = 0; i < ONFI_EXT_SECTION_MAX; i++) {
+ s = ep->sections + i;
+ if (s->type == ONFI_SECTION_TYPE_2)
+ break;
+ cursor += s->length * 16;
+ }
+ if (i == ONFI_EXT_SECTION_MAX) {
+ pr_debug("We can not find the ECC section.\n");
+ goto ext_out;
+ }
+
+ /* get the info we want. */
+ ecc = (struct onfi_ext_ecc_info *)cursor;
+
+ if (ecc->codeword_size) {
+ chip->ecc_strength_ds = ecc->ecc_bits;
+ chip->ecc_step_ds = 1 << ecc->codeword_size;
+ }
+
+ pr_info("ONFI extended param page detected.\n");
+ return 0;
+
+ext_out:
+ kfree(ep);
+ return ret;
+}
+
/*
* Check if the NAND chip is ONFI compliant, returns 1 if it is, 0 otherwise.
*/
if (p->ecc_bits != 0xff) {
chip->ecc_strength_ds = p->ecc_bits;
chip->ecc_step_ds = 512;
+ } else if (chip->onfi_version >= 21 &&
+ (onfi_feature(chip) & ONFI_FEATURE_EXT_PARAM_PAGE)) {
+
+ /*
+ * The nand_flash_detect_ext_param_page() uses the
+ * Change Read Column command which maybe not supported
+ * by the chip->cmdfunc. So try to update the chip->cmdfunc
+ * now. We do not replace user supplied command function.
+ */
+ if (mtd->writesize > 512 && chip->cmdfunc == nand_command)
+ chip->cmdfunc = nand_command_lp;
+
+ /* The Extended Parameter Page is supported since ONFI 2.1. */
+ if (nand_flash_detect_ext_param_page(mtd, chip, p))
+ pr_info("Failed to detect the extended param page.\n");
}
pr_info("ONFI flash detected\n");