Re: [PATCH V3 3/6] MTD : add the database for the NANDs

[Huang Shijie <b32955@freescale.com>]

Hi Florian:

> Hello Huang,
>
> On Wednesday 30 March 2011 11:05:59 Huang Shijie wrote:
>> Hi Florian:
>>
>> thanks for a so quick reply. :)
>>
>>> Hello Huang,
>>>
>>> On Wednesday 30 March 2011 10:40:10 Huang Shijie wrote:
>>>> This is a new database for the NANDs which is searched by the id_bytes.
>>> drivers/mtd//nand/nand_base.c will be able to detect all of your chips
>>> listed below based on the ids present in drivers/mtd/nand/nand_ids.c
>> yes.
>>
>> But I will use the new database to replace the old one.
>>
>> I will  submit new patches to modify the generic code if my driver is
>> accepted.
> I think you can start right away submitting patches to modify generic code,
> this can either be a premilinary patch series to the GPMI driver, or in the
> same patch series as the GPMI driver.
>
I prefer to change the generic code after the driver is merged.
thanks.

I am too busy to change it right now.
>>> If you have new chips to support in the future, you should add them in
>>> drivers/mtd/nand/nand_ids.c and not keep this file.
>> The data structure  nand_flash_dev{} does not contain enough information.
>> So I want to the nand_device_info{} to replace it in future.
> Ok, you should have written that in the patch description, otherwise it is
> misleading and I though you just duplicated code without knowing what the
> existing code could do.
>
my fault.

>>> I still do not understand why this would be needed, is it because the
>>> generic code does not provide enough informations for your driver?
>> yes.
>>
>> IMHO, the generic code is somehow trapped in a wrong way. :(
>> Paring the id bytes is not sufficient to get all the information you
>> need which is faced by me.
>>
>> What's more, I think the paring code is ugly, see the
>> nand_get_flash_type().
>>
>> Why not create a new database which contains all the necessary
>> information for a nand, and can be easy
>> find by the id bytes as the keyword?
> The idea is to hardcode as little information as possible, and let the rest be
> detected at runtime when possible. I think this it the right approach, because
> it is more future proof.
>
thanks.
>> I wish David and Artem give some advice about this.
> I would also like them to jump into this discussion.
>
me too:)
>>>> Signed-off-by: Huang Shijie<b32955@freescale.com>
>>>> ---
>>>>
>>>>    drivers/mtd/nand/nand_device_info.c |  157
>>>>
>>>> +++++++++++++++++++++++++++++++++++ drivers/mtd/nand/nand_device_info.h
>>>> |
>>>>
>>>>    88 +++++++++++++++++++
>>>>    2 files changed, 245 insertions(+), 0 deletions(-)
>>>>    create mode 100644 drivers/mtd/nand/nand_device_info.c
>>>>    create mode 100644 drivers/mtd/nand/nand_device_info.h
>>>>
>>>> diff --git a/drivers/mtd/nand/nand_device_info.c
>>>> b/drivers/mtd/nand/nand_device_info.c new file mode 100644
>>>> index 0000000..757ed89
>>>> --- /dev/null
>>>> +++ b/drivers/mtd/nand/nand_device_info.c
>>>> @@ -0,0 +1,157 @@
>>>> +/*
>>>> + * Copyright (C) 2011 Freescale Semiconductor, Inc. All Rights
>>>> Reserved. + */
>>>> +
>>>> +/*
>>>> + * The code contained herein is licensed under the GNU General Public
>>>> + * License. You may obtain a copy of the GNU General Public License
>>>> + * Version 2 or later at the following locations:
>>>> + *
>>>> + * http://www.opensource.org/licenses/gpl-license.html
>>>> + * http://www.gnu.org/copyleft/gpl.html
>>>> + */
>>>> +#include<asm/sizes.h>
>>>> +#include<linux/mtd/nand.h>
>>>> +
>>>> +#include "nand_device_info.h"
>>>> +
>>>> +static const struct nand_device_info samsung_nand[] = {
>>>> +	{
>>>> +		.id	= { 0xec, 0xd3, 0x14, 0x25, 0x64, 0xec, 0xd3, 0x14 },
>>>> +		.id_len	= 8,
>>>> +		.desc	= "K9G8G08U0M, K9HAG08U1M",
>>>> +		.attr	= ATTR(MLC, NAND_BUSWIDTH_8, 1LL * SZ_1G, 128,
>>>> +				2 * SZ_1K + 64, 8, 512),
>>>> +	}, {
>>>> +		.id	= { 0xec, 0xd7, 0xd5, 0x29, 0x38, 0x41, 0xec, 0xd7 },
>>>> +		.id_len	= 8,
>>>> +		.desc	= "K9LBG08U0D",
>>>> +		.attr	= ATTR(MLC, NAND_BUSWIDTH_8, 4LL * SZ_1G, 128,
>>>> +				4 * SZ_1K + 218, 16, 512),
>>>> +	}, {
>>>> +		.id	= { 0xec, 0xd5, 0x14, 0xb6, 0x74, 0xec, 0xd5, 0x14 },
>>>> +		.id_len	= 8,
>>>> +		.desc	= "K9GAG08U0M",
>>>> +		.attr	= ATTR(MLC, NAND_BUSWIDTH_8, 2LL * SZ_1G, 128,
>>>> +				4 * SZ_1K + 218, 16, 512),
>>>> +	}, {
>>>> +		/* end of the table. */
>>>> +		.id	= { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 },
>>>> +	},
>>>> +};
>>>> +
>>>> +/* macro to get the id bytes */
>>>> +#define ID_GET_MFR_CODE(id)  ((id)[0])
>>>> +
>>>> +void nand_device_print_info(struct nand_device_info *info)
>>>> +{
>>>> +	unsigned    i;
>>>> +	const char  *mfr_name;
>>>> +	const char  *cell_technology_name;
>>>> +	uint64_t    chip_size;
>>>> +	const char  *chip_size_units;
>>>> +	unsigned    page_size;
>>>> +	unsigned    oob_size;
>>>> +	struct nand_attr *attr		=&info->attr;
>>>> +
>>>> +	/* Prepare the manufacturer name. */
>>>> +	mfr_name = "Unknown";
>>>> +	for (i = 0; nand_manuf_ids[i].id; i++) {
>>>> +		if (nand_manuf_ids[i].id == ID_GET_MFR_CODE(info->id)) {
>>>> +			mfr_name = nand_manuf_ids[i].name;
>>>> +			break;
>>>> +		}
>>>> +	}
>>>> +
>>>> +	/* Prepare the name of the cell technology. */
>>>> +	switch (attr->cell_technology) {
>>>> +	case SLC:
>>>> +		cell_technology_name = "SLC";
>>>> +		break;
>>>> +	case MLC:
>>>> +		cell_technology_name = "MLC";
>>>> +		break;
>>>> +	default:
>>>> +		cell_technology_name = "Unknown";
>>>> +		break;
>>>> +	}
>>>> +
>>>> +	/* Prepare the chip size. */
>>>> +	if ((attr->chip_size_in_bytes>= SZ_1G)&&
>>>> +					!(attr->chip_size_in_bytes % SZ_1G)) {
>>>> +		chip_size       = attr->chip_size_in_bytes / ((uint64_t)
> SZ_1G);
>>>> +		chip_size_units = "GiB";
>>>> +	} else if ((attr->chip_size_in_bytes>= SZ_1M)&&
>>>> +					!(attr->chip_size_in_bytes % SZ_1M)) {
>>>> +		chip_size       = attr->chip_size_in_bytes / ((uint64_t)
> SZ_1M);
>>>> +		chip_size_units = "MiB";
>>>> +	} else {
>>>> +		chip_size       = attr->chip_size_in_bytes;
>>>> +		chip_size_units = "B";
>>>> +	}
>>>> +
>>>> +	/* Prepare the page geometry. */
>>>> +	page_size = (1<<   (fls(attr->page_total_size_in_bytes) - 1));
>>>> +	oob_size  = attr->page_total_size_in_bytes - page_size;
>>>> +
>>>> +	/* Print the infomation. */
>>>> +	pr_info("--------------------------------------\n");
>>>> +	pr_info("	NAND device infomation (RAW)\n");
>>>> +	pr_info("--------------------------------------\n");
>>>> +	pr_info("Manufacturer      : %s (0x%02x)\n", mfr_name, info->id[0]);
>>>> +	pr_info("Device Code       : 0x%02x\n", info->id[1]);
>>>> +	pr_info("Cell Technology   : %s\n", cell_technology_name);
>>>> +	pr_info("Chip Size         : %llu %s\n", chip_size,
> chip_size_units);
>>>> +	pr_info("Pages per Block   : %u\n", attr->block_size_in_pages);
>>>> +	pr_info("Page Geometry     : %u+%u\n", page_size, oob_size);
>>>> +	pr_info("ECC Strength      : %u bits\n", attr-
>> ecc_strength_in_bits);
>>>> +	pr_info("ECC Size          : %u B\n", attr->ecc_size_in_bytes);
>>>> +	pr_info("Description       : %s\n", info->desc);
>>>> +}
>>>> +
>>>> +static struct nand_device_info * __init
>>>> +search_table(const struct nand_device_info *table, const uint8_t id[])
>>>> +{
>>>> +	struct nand_device_info *info = (struct nand_device_info *)table;
>>>> +
>>>> +	while (ID_GET_MFR_CODE(info->id)) {
>>>> +		int i;
>>>> +
>>>> +		/* match all the valid id bytes. Is it too strict? */
>>>> +		for (i = 0; i<   info->id_len; i++)
>>>> +			if (info->id[i] != id[i])
>>>> +				break;
>>>> +
>>>> +		/* found it */
>>>> +		if (i == info->id_len)
>>>> +			return info;
>>>> +		info++;
>>>> +	}
>>>> +	return NULL;
>>>> +}
>>>> +
>>>> +struct nand_device_mfr_info {
>>>> +	uint8_t                  id;
>>>> +	const struct nand_device_info  *table;
>>>> +};
>>>> +
>>>> +static const struct nand_device_mfr_info  nand_device_mfr_directory[] =
>>>> { +	{ NAND_MFR_SAMSUNG, samsung_nand },
>>>> +	{ 0, NULL },
>>>> +};
>>>> +
>>>> +struct nand_device_info *nand_device_get_info(const uint8_t id[])
>>>> +{
>>>> +	uint8_t mfr_id = ID_GET_MFR_CODE(id);
>>>> +	unsigned i;
>>>> +
>>>> +	for (i = 0; nand_device_mfr_directory[i].id; i++) {
>>>> +		if (nand_device_mfr_directory[i].id == mfr_id) {
>>>> +			const struct nand_device_info  *table;
>>>> +
>>>> +			table = nand_device_mfr_directory[i].table;
>>>> +			return search_table(table, id);
>>>> +		}
>>>> +	}
>>>> +	return NULL;
>>>> +}
>>>> diff --git a/drivers/mtd/nand/nand_device_info.h
>>>> b/drivers/mtd/nand/nand_device_info.h new file mode 100644
>>>> index 0000000..15f688d
>>>> --- /dev/null
>>>> +++ b/drivers/mtd/nand/nand_device_info.h
>>>> @@ -0,0 +1,88 @@
>>>> +/*
>>>> + * Copyright 2011 Freescale Semiconductor, Inc. All Rights Reserved.
>>>> + */
>>>> +
>>>> +/*
>>>> + * The code contained herein is licensed under the GNU General Public
>>>> + * License. You may obtain a copy of the GNU General Public License
>>>> + * Version 2 or later at the following locations:
>>>> + *
>>>> + * http://www.opensource.org/licenses/gpl-license.html
>>>> + * http://www.gnu.org/copyleft/gpl.html
>>>> + */
>>>> +#ifndef __DRIVERS_NAND_DEVICE_INFO_H
>>>> +#define __DRIVERS_NAND_DEVICE_INFO_H
>>>> +
>>>> +enum nand_device_cell_technology {
>>>> +	SLC = 0,
>>>> +	MLC = 1,
>>>> +};
>>>> +
>>>> +/**
>>>> + * @cell_technology:		The storage cell technology.
>>>> + * @busw:			The bus width of the NAND.
>>>> + * @chip_size_in_bytes:		The total size of the storage behind a
> single
>>>> + *				chip select, in bytes. Notice that this is *not*
>>>> + *				necessarily the total size of the storage in a
>>>> + *				*package*, which may contain several chips.
>>>> + * @block_size_in_pages:	The number of pages in a block.
>>>> + * @page_total_size_in_bytes:	The total size of a page, in bytes,
>>>> including + *				both the data and the OOB.
>>>> + * @ecc_strength_in_bits:	The strength of the ECC called for by the
>>>> + *				manufacturer, in number of correctable bits.
>>>> + * @ecc_size_in_bytes:		The size of the data block over which the
>>>> + *				manufacturer calls for the given ECC algorithm
>>>> + *				and strength.
>>>> + */
>>>> +struct nand_attr {
>>>> +	/* Technology */
>>>> +	enum nand_device_cell_technology  cell_technology;
>>>> +
>>>> +	/* bus width */
>>>> +#define NAND_BUSWIDTH_8	0
>>>> +	uint32_t	busw;
>>>> +
>>>> +	/* Geometry */
>>>> +	uint64_t	chip_size_in_bytes;
>>>> +	uint32_t	block_size_in_pages;
>>>> +	uint32_t	page_total_size_in_bytes;
>>>> +
>>>> +	/* ECC */
>>>> +	uint16_t	ecc_strength_in_bits;
>>>> +	uint16_t	ecc_size_in_bytes;
>>>> +};
>>>> +
>>>> +#define ID_BYTES	(8)
>>>> +/*
>>>> + * struct nand_device_info - Information about a single NAND Flash
>>>> device. + *
>>>> + * This structure contains all the *essential* information about a NAND
>>>> Flash + * device, derived from the device's data sheet.
>>>> + */
>>>> +struct nand_device_info {
>>>> +	/* id */
>>>> +	uint8_t			id[ID_BYTES];
>>>> +	unsigned int		id_len;
>>>> +
>>>> +	/* Description */
>>>> +	const char		*desc;
>>>> +
>>>> +	/* attribute*/
>>>> +	struct nand_attr	attr;
>>>> +};
>>>> +
>>>> +/* macro for the NAND attribute */
>>>> +#define ATTR(_a, _b, _c, _d, _e, _f, _g)		\
>>>> +	{						\
>>>> +		.cell_technology		= (_a),	\
>>>> +		.busw				= (_b),	\
>>>> +		.chip_size_in_bytes		= (_c),	\
>>>> +		.block_size_in_pages		= (_d),	\
>>>> +		.page_total_size_in_bytes	= (_e),	\
>>>> +		.ecc_strength_in_bits		= (_f),	\
>>>> +		.ecc_size_in_bytes		= (_g),	\
>>>> +	}
>>>> +
>>>> +struct nand_device_info *nand_device_get_info(const uint8_t
>>>> id_bytes[]); +void nand_device_print_info(struct nand_device_info
>>>> *info);
>>>> +#endif
>> Best Regards
>> Huang Shijie
>>
>>
>>
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>> linux-arm-kernel mailing list
>> linux-arm-kernel@lists.infradead.org
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Best Regards
Huang Shijie