+ * omap_enable_hwecc - configures GPMC as per ECC scheme before read/write
+ * @mtd: MTD device structure
+ * @mode: Read/Write mode
+ */
+__maybe_unused
+static void omap_enable_hwecc(struct mtd_info *mtd, int32_t mode)
+{
+ struct nand_chip *nand = mtd->priv;
+ struct omap_nand_info *info = nand->priv;
+ unsigned int dev_width = (nand->options & NAND_BUSWIDTH_16) ? 1 : 0;
+ unsigned int ecc_algo = 0;
+ unsigned int bch_type = 0;
+ unsigned int eccsize1 = 0x00, eccsize0 = 0x00, bch_wrapmode = 0x00;
+ u32 ecc_size_config_val = 0;
+ u32 ecc_config_val = 0;
+ int cs = info->cs;
+
+ /* configure GPMC for specific ecc-scheme */
+ switch (info->ecc_scheme) {
+ case OMAP_ECC_HAM1_CODE_SW:
+ return;
+ case OMAP_ECC_HAM1_CODE_HW:
+ ecc_algo = 0x0;
+ bch_type = 0x0;
+ bch_wrapmode = 0x00;
+ eccsize0 = 0xFF;
+ eccsize1 = 0xFF;
+ break;
+ case OMAP_ECC_BCH8_CODE_HW_DETECTION_SW:
+ case OMAP_ECC_BCH8_CODE_HW:
+ ecc_algo = 0x1;
+ bch_type = 0x1;
+ if (mode == NAND_ECC_WRITE) {
+ bch_wrapmode = 0x01;
+ eccsize0 = 0; /* extra bits in nibbles per sector */
+ eccsize1 = 28; /* OOB bits in nibbles per sector */
+ } else {
+ bch_wrapmode = 0x01;
+ eccsize0 = 26; /* ECC bits in nibbles per sector */
+ eccsize1 = 2; /* non-ECC bits in nibbles per sector */
+ }
+ break;
+ case OMAP_ECC_BCH16_CODE_HW:
+ ecc_algo = 0x1;
+ bch_type = 0x2;
+ if (mode == NAND_ECC_WRITE) {
+ bch_wrapmode = 0x01;
+ eccsize0 = 0; /* extra bits in nibbles per sector */
+ eccsize1 = 52; /* OOB bits in nibbles per sector */
+ } else {
+ bch_wrapmode = 0x01;
+ eccsize0 = 52; /* ECC bits in nibbles per sector */
+ eccsize1 = 0; /* non-ECC bits in nibbles per sector */
+ }
+ break;
+ default:
+ return;
+ }
+ /* Clear ecc and enable bits */
+ writel(ECCCLEAR | ECCRESULTREG1, &gpmc_cfg->ecc_control);
+ /* Configure ecc size for BCH */
+ ecc_size_config_val = (eccsize1 << 22) | (eccsize0 << 12);
+ writel(ecc_size_config_val, &gpmc_cfg->ecc_size_config);
+
+ /* Configure device details for BCH engine */
+ ecc_config_val = ((ecc_algo << 16) | /* HAM1 | BCHx */
+ (bch_type << 12) | /* BCH4/BCH8/BCH16 */
+ (bch_wrapmode << 8) | /* wrap mode */
+ (dev_width << 7) | /* bus width */
+ (0x0 << 4) | /* number of sectors */
+ (cs << 1) | /* ECC CS */
+ (0x1)); /* enable ECC */
+ writel(ecc_config_val, &gpmc_cfg->ecc_config);
+}
+
+/*
+ * omap_calculate_ecc - Read ECC result
+ * @mtd: MTD structure
+ * @dat: unused
+ * @ecc_code: ecc_code buffer