From 3f4eb14bdbe148fcc3a8e02f506ccc9b8c955ad4 Mon Sep 17 00:00:00 2001 From: Pekon Gupta Date: Thu, 20 Mar 2014 18:48:34 +0530 Subject: mtd: devices: elm: check for hardware engine's design constraints ELM hardware engine is used by BCH ecc-schemes for detecting and locating ECC errors. This patch adds the following checks for ELM hardware engine: - ELM internal buffers are of 1K, so it cannot process data with ecc-step-size > 1K. - ELM engine can execute upto maximum of 8 threads in parallel, so in *page-mode* (when complete page is processed in single iteration), ELM cannot support ecc-steps > 8. Signed-off-by: Pekon Gupta Reviewed-by: Ezequiel Garcia Signed-off-by: Brian Norris --- drivers/mtd/nand/omap2.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) (limited to 'drivers/mtd/nand') diff --git a/drivers/mtd/nand/omap2.c b/drivers/mtd/nand/omap2.c index ab9c472456d9..6f9b339aed74 100644 --- a/drivers/mtd/nand/omap2.c +++ b/drivers/mtd/nand/omap2.c @@ -1540,6 +1540,8 @@ static int is_elm_present(struct omap_nand_info *info, struct device_node *elm_node, enum bch_ecc bch_type) { struct platform_device *pdev; + struct nand_ecc_ctrl *ecc = &info->nand.ecc; + int err; /* check whether elm-id is passed via DT */ if (!elm_node) { pr_err("nand: error: ELM DT node not found\n"); @@ -1553,9 +1555,10 @@ static int is_elm_present(struct omap_nand_info *info, } /* ELM module available, now configure it */ info->elm_dev = &pdev->dev; - if (elm_config(info->elm_dev, bch_type)) - return -ENODEV; - return 0; + err = elm_config(info->elm_dev, bch_type, + (info->mtd.writesize / ecc->size), ecc->size, ecc->bytes); + + return err; } #endif /* CONFIG_MTD_NAND_ECC_BCH */ -- cgit v1.2.3