3  * Support for Realtek hardware ECC engine in RTL93xx SoCs
14  * The Realtek ECC engine has two operation modes.
16  * - BCH6  : Generate 10 ECC bytes from 512 data bytes plus 6 free bytes
17  * - BCH12 : Generate 20 ECC bytes from 512 data bytes plus 6 free bytes
20  * are only two known devices in the wild that have NAND flash and make use of this ECC engine
25  * This driver aligns with kernel ECC naming conventions. Neverthless a short notice on the
28  * - BBI      : Bad block indicator. The first two bytes of OOB. Protected by ECC!
29  * - tag      : 6 User/free bytes. First tag "contains" 2 bytes BBI. Protected by ECC!
30  * - syndrome : ECC/parity bytes
37  * | data | data | data | data | BBI | free | free | free | free | ECC | ECC | ECC | ECC |
101 	return nand->ecc.ctx.priv;  in nand_to_ctx()
106 	struct nand_ecc_engine *eng = nand->ecc.engine;  in nand_to_rtlc()
145 	.ecc = rtl_ecc_ooblayout_ecc,
168 	 * The ECC engine needs 6-8 us to encode/decode a BCH6 syndrome for 512 bytes of data  in rtl_ecc_wait_for_engine()
250 		dev_dbg(rtlc->dev, "ECC calculation failed\n");  in rtl_ecc_prepare_io_req()
280 			/* ECC totally fails for bitflips in erased blocks */  in rtl_ecc_finish_io_req()
301 		dev_dbg(rtlc->dev, "ECC correction failed\n");  in rtl_ecc_finish_io_req()
311 	struct device *dev = nand->ecc.engine->dev;  in rtl_ecc_check_support()
320 	if (nand->ecc.user_conf.algo != NAND_ECC_ALGO_BCH ||  in rtl_ecc_check_support()
321 	    nand->ecc.user_conf.strength != RTL_ECC_ALLOWED_STRENGTH ||  in rtl_ecc_check_support()
322 	    nand->ecc.user_conf.placement != NAND_ECC_PLACEMENT_OOB ||  in rtl_ecc_check_support()
323 	    nand->ecc.user_conf.step_size != RTL_ECC_BLOCK_SIZE) {  in rtl_ecc_check_support()
334 	struct nand_ecc_props *conf = &nand->ecc.ctx.conf;  in rtl_ecc_init_ctx()
337 	int strength = nand->ecc.user_conf.strength;  in rtl_ecc_init_ctx()
338 	struct device *dev = nand->ecc.engine->dev;  in rtl_ecc_init_ctx()
350 	nand->ecc.ctx.priv = ctx;  in rtl_ecc_init_ctx()
447 		.compatible = "realtek,rtl9301-ecc",
454 		.name = "rtl-nand-ecc-engine",
464 MODULE_DESCRIPTION("Realtek NAND hardware ECC controller");