[PATCH v11 2/4] MTD: at91: add dt parameters for Atmel PMECC
Josh Wu
josh.wu at atmel.com
Tue Jun 26 02:05:10 EDT 2012
On 6/25/2012 6:35 PM, Richard Genoud wrote:
> 2012/6/25 Josh Wu <josh.wu at atmel.com>:
>> Add DT support for PMECC parameters.
>>
>> Signed-off-by: Hong Xu <hong.xu at atmel.com>
>> Signed-off-by: Josh Wu <josh.wu at atmel.com>
>> ---
>> .../devicetree/bindings/mtd/atmel-nand.txt | 9 ++++
>> drivers/mtd/nand/atmel_nand.c | 52 +++++++++++++++++++-
>> 2 files changed, 60 insertions(+), 1 deletion(-)
>>
>> diff --git a/Documentation/devicetree/bindings/mtd/atmel-nand.txt b/Documentation/devicetree/bindings/mtd/atmel-nand.txt
>> index a200695..ed6927a 100644
>> --- a/Documentation/devicetree/bindings/mtd/atmel-nand.txt
>> +++ b/Documentation/devicetree/bindings/mtd/atmel-nand.txt
>> @@ -16,6 +16,15 @@ Optional properties:
>> - nand-ecc-mode : String, operation mode of the NAND ecc mode, soft by default.
>> Supported values are: "none", "soft", "hw", "hw_syndrome", "hw_oob_first",
>> "soft_bch".
>> +- atmel,has-pmecc : boolean to enable Programmable Multibit ECC hardware.
>> + Only supported by at91sam9x5 or later sam9 product.
>> +- atmel,pmecc-cap : error correct capability for Programmable Multibit ECC
>> + Controller. Supported values are: 2, 4, 8, 12, 24.
>> +- atmel,pmecc-sector-size : sector size for ECC computation. Supported values
>> + are: 512, 1024.
>> +- atmel,pmecc-lookup-table-offset : includes two offsets of lookup table in ROM
>> + for different sector size. First one is for sector size 512, the next is for
>> + sector size 1024.
>> - nand-bus-width : 8 or 16 bus width if not present 8
>> - nand-on-flash-bbt: boolean to enable on flash bbt option if not present false
>>
> Maybe you should update the reg parameter documentation with the
> needed resources.
>
I will update the reg parameter documentation and add one example for
PMECC setting. thanks.
>> diff --git a/drivers/mtd/nand/atmel_nand.c b/drivers/mtd/nand/atmel_nand.c
>> index 7a41a04..b97ad9f 100644
>> --- a/drivers/mtd/nand/atmel_nand.c
>> +++ b/drivers/mtd/nand/atmel_nand.c
>> @@ -93,6 +93,11 @@ struct atmel_nand_host {
>>
>> struct completion comp;
>> struct dma_chan *dma_chan;
>> +
>> + bool has_pmecc;
>> + u8 pmecc_corr_cap;
>> + u16 pmecc_sector_size;
>> + u32 pmecc_lookup_table_offset;
>> };
>>
>> static int cpu_has_dma(void)
>> @@ -481,7 +486,8 @@ static void atmel_nand_hwctl(struct mtd_info *mtd, int mode)
>> static int __devinit atmel_of_init_port(struct atmel_nand_host *host,
>> struct device_node *np)
>> {
>> - u32 val;
>> + u32 val, table_offset;
>> + u32 offset[2];
>> int ecc_mode;
>> struct atmel_nand_data *board = &host->board;
>> enum of_gpio_flags flags;
>> @@ -517,6 +523,50 @@ static int __devinit atmel_of_init_port(struct atmel_nand_host *host,
>> board->enable_pin = of_get_gpio(np, 1);
>> board->det_pin = of_get_gpio(np, 2);
>>
>> + host->has_pmecc = of_property_read_bool(np, "atmel,has-pmecc");
>> +
>> + if (!(board->ecc_mode == NAND_ECC_HW) || !host->has_pmecc)
>> + return 0; /* Not using PMECC */
>> +
>> + /* use PMECC, get correction capability, sector size and lookup
>> + * table offset.
>> + */
>> + if (of_property_read_u32(np, "atmel,pmecc-cap", &val) != 0) {
>> + dev_err(host->dev, "Cannot decide PMECC Capability\n");
>> + return -EINVAL;
>> + } else if ((val != 2) && (val != 4) && (val != 8) && (val != 12) &&
>> + (val != 24)) {
>> + dev_err(host->dev,
>> + "Unsupported PMECC correction capability: %d; should be 2, 4, 8, 12 or 24\n",
>> + val);
>> + return -EINVAL;
>> + }
>> + host->pmecc_corr_cap = (u8)val;
>> +
>> + if (of_property_read_u32(np, "atmel,pmecc-sector-size", &val) != 0) {
>> + dev_err(host->dev, "Cannot decide PMECC Sector Size\n");
>> + return -EINVAL;
>> + } else if ((val != 512) && (val != 1024)) {
>> + dev_err(host->dev,
>> + "Unsupported PMECC sector size: %d; should be 512 or 1024 bytes\n",
>> + val);
>> + return -EINVAL;
>> + }
>> + host->pmecc_sector_size = (u16)val;
>> +
>> + if (of_property_read_u32_array(np, "atmel,pmecc-lookup-table-offset",
>> + offset, 2) != 0) {
>> + dev_err(host->dev, "Cannot get PMECC lookup table offset\n");
>> + return -EINVAL;
>> + }
>> + table_offset = host->pmecc_sector_size == 512 ? offset[0] : offset[1];
>> +
>> + if (!table_offset) {
>> + dev_err(host->dev, "Invalid PMECC lookup table offset\n");
>> + return -EINVAL;
>> + }
>> + host->pmecc_lookup_table_offset = table_offset;
>> +
>> return 0;
>> }
>> #else
>> --
>> 1.7.9.5
>>
>>
>> ______________________________________________________
>> Linux MTD discussion mailing list
>> http://lists.infradead.org/mailman/listinfo/linux-mtd/
> Richard.
>
Best Regards,
Josh Wu
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