[U-Boot] [PATCH v1 3/7] nand: add nand mtd concat support

[Heiko Schocher]

Hello Scott,

Am 25.05.2016 um 07:30 schrieb Scott Wood:
> On 05/25/2016 12:07 AM, Heiko Schocher wrote:
>> add for nand devices mtd concat support. Generic MTD concat
>> support is already ported to mainline, and used in the cfi_mtd
>> driver. This patch adds it similiar for nand devices.
>>
>> Signed-off-by: Heiko Schocher <hs at denx.de>
>> ---
>>
>>   drivers/mtd/nand/nand.c | 29 +++++++++++++++++++++++++++++
>>   1 file changed, 29 insertions(+)
>>
>> diff --git a/drivers/mtd/nand/nand.c b/drivers/mtd/nand/nand.c
>> index 8f0a921..5413123 100644
>> --- a/drivers/mtd/nand/nand.c
>> +++ b/drivers/mtd/nand/nand.c
>> @@ -9,6 +9,7 @@
>>   #include <common.h>
>>   #include <nand.h>
>>   #include <errno.h>
>> +#include <linux/mtd/concat.h>
>>
>>   #ifndef CONFIG_SYS_NAND_BASE_LIST
>>   #define CONFIG_SYS_NAND_BASE_LIST { CONFIG_SYS_NAND_BASE }
>> @@ -30,6 +31,12 @@ static char dev_name[CONFIG_SYS_MAX_NAND_DEVICE][8];
>>
>>   static unsigned long total_nand_size; /* in kiB */
>>
>> +#ifdef CONFIG_MTD_CONCAT
>> +static int nand_devices_found;
>> +static struct mtd_info *mtd_nand_list[CONFIG_SYS_MAX_NAND_DEVICE];
>> +static char c_mtd_name[16];
>> +#endif
>
> Why is c_mtd_name file-scope rather than local?

fixed.

>> +
>>   /* Register an initialized NAND mtd device with the U-Boot NAND command. */
>>   int nand_register(int devnum)
>>   {
>> @@ -49,6 +56,9 @@ int nand_register(int devnum)
>>   	 * via the mtdcore infrastructure (e.g. ubi).
>>   	 */
>>   	add_mtd_device(mtd);
>> +#ifdef CONFIG_MTD_CONCAT
>> +	mtd_nand_list[nand_devices_found++] = mtd;
>> +#endif
>
> Why do we need another list of NAND devices?  Use nand_info[].

Ah, correct ... struct nand_info_t == struct mtd_info ... Hmm...
why we need a "struct nand_info_t" ?

>>   #endif
>>
>>   	total_nand_size += mtd->size / 1024;
>> @@ -102,4 +112,23 @@ void nand_init(void)
>>   	 */
>>   	board_nand_select_device(nand_info[nand_curr_device].priv, nand_curr_device);
>>   #endif
>> +
>> +#ifdef CONFIG_MTD_CONCAT
>> +	if (nand_devices_found > 1) {
>> +		struct mtd_info *mtd;
>> +
>> +		/*
>> +		 * We detected multiple devices. Concatenate them together.
>> +		 */
>> +		sprintf(c_mtd_name, "nand%d", nand_devices_found);
>> +		mtd = mtd_concat_create(mtd_nand_list, nand_devices_found,
>> +					c_mtd_name);
>> +
>> +		if (mtd == NULL)
>> +			return;
>> +
>> +		if (add_mtd_device(mtd))
>> +			return;
>> +	}
>> +#endif /* CONFIG_MTD_CONCAT */
>>   }
>
> Please don't add new features that depend on the old-style NAND init.

Hmm... my add works for the "#ifdef CONFIG_SYS_NAND_SELF_INIT" case
and the "else" case ... where would be the appropriate place?

bye,
Heiko
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