Re: JEDEC support broken?

Re: JEDEC support broken?

[Erwin Authried]

Alice Hennessy[SMTP:ahennessy@mvista.com] wrote:
> I have a board that needs support for both cfi and jedec flashes.   So,
> the approach
> I have taken is to use physmap.c with an array of "physmap_info" structures
> that describe the window
> address, window size, buswidth and number of partitions for each flash.  I
> also use a double array of
> mtd_partition structures to divide each flash into partitions (making use
> of mtdpart.c).   This allows multiple
> flashes to be described in one mapping file so the file is really a
> description of a particular board.  There is
> a probe for a cfi flash  and if that fails, then a probe for a jedec
> flash.    This eliminates the use of
> CONFIG_MTD_PHYSMAP_START  (and len and buswidth).   Is this in keeping with
> the intent
> of the map file?
> 
> Alice
> 
I'd like to spin your idea a little bit further: Instead of having a description of a particular
board, I'd prefer to have one "generic" linear mapping file that is able to probe for 
flash in an adress range that is specified during configuration (starting adress and
length or end of the adress range, and possibly the adress increments for probing, e.g. 1MB).
This way, you would be able to support virtually all boards that carry linear, non-banked flash
without needing a specialized file for every board. That would be especially useful for uClinux ...

-erwin



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RE: JEDEC support broken?

[quine]

I'm not sure how I got on your email list,  please remove my email address
quine@ftel.net

-----Original Message-----
From: David Woodhouse [mailto:dwmw2@infradead.org]
Sent: Tuesday, November 14, 2000 5:44 PM
To: Alice Hennessy
Cc: Erwin Authried; 'mtd@infradead.org'
Subject: Re: JEDEC support broken?


On Tue, 14 Nov 2000, Alice Hennessy wrote:

> Do you mean to use map->size instead of bank_size (to spread the
> individual start offsets over if there are gaps between chips)

Nope, discard the concept of bank_size altogether. Each chip needs its own
information structure, much like the 'struct flchip' in
include/mtd/flashchip.h, which contains the start offset of the chip in
the map.

It's reasonable to assume that all chips in the array will be the same
size. You have an array of struct flchip (or your equivalent if you don't
want to use struct flchip) and you index into that by dividing by the
individual chip size - and then just address the chip you've selected by
using the start offset listed for it.

> Also,  is spin_lock support going to be added in jedec.c?

It certainly _needs_ doing. Feel free :)

> I have a board that needs support for both cfi and jedec flashes.
> So, the approach I have taken is to use physmap.c with an array of
> "physmap_info" structures that describe the window address, window
> size, buswidth and number of partitions for each flash.
 < ... deletia ... >

> Is this in keeping with the intent of the map file?

Sounds like it. Show us the code though.

-- 
dwmw2




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JEDEC support broken?

[Erwin Authried]

With several patches, I'm able to compile most of the MTD devices and chip drivers 
for uClinux now. There are problems with jedec.c, the compiler complains about 
the missing "bank_size" in the "map_info" structure. What's wrong with jedec.c?

Is there a driver that is able to use a physically mapped flash that doesn't support
CFI? I think it would be best to probe for CFI, and then for JEDEC in physmap.c.

-Erwin





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Re: JEDEC support broken?

[David Woodhouse]

eauth@softsys.co.at said:
> With several patches, I'm able to compile most of the MTD devices and
> chip drivers  for uClinux now. There are problems with jedec.c, the
> compiler complains about  the missing "bank_size" in the "map_info"
> structure. What's wrong with jedec.c?

It's been half-ported to the map stuff, but not completely. Remove all 
references to bank_size and keep a start offset in the individual flash 
chip structures.

> Is there a driver that is able to use a physically mapped flash that
> doesn't support CFI? I think it would be best to probe for CFI, and
> then for JEDEC in physmap.c.

Agreed. Let me finish merging the inter_module_xxx() stuff before you do 
that, though.

--
dwmw2




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Re: JEDEC support broken?

[Alice Hennessy]

David Woodhouse wrote:

> eauth@softsys.co.at said
> > With several patches, I'm able to compile most of the MTD devices and
> > chip drivers  for uClinux now. There are problems with jedec.c, the
> > compiler complains about  the missing "bank_size" in the "map_info"
> > structure. What's wrong with jedec.c?
>
> It's been half-ported to the map stuff, but not completely. Remove all
> references to bank_size and keep a start offset in the individual flash
> chip structures.

I am using jedec.c after making a few quick changes, ie making
bank_size a static variable and setting to map->size and setting
priv.size to bank_size, fleshing out jedec_probe8() and making a few other
small changes.
I'm using mtdpart.c for partitioning of the flash.    It seems to work fine
but only
because I have one flash chip.    Do you mean to use map->size instead of
bank_size (to spread the individual start offsets over if there are gaps
between chips)  and
start offset instead of bank_fill[0] to skip over gaps in flash_write and
jedec_read_banked?
Also,  is spin_lock support going to be added in jedec.c?




>
>
> > Is there a driver that is able to use a physically mapped flash that
> > doesn't support CFI? I think it would be best to probe for CFI, and
> > then for JEDEC in physmap.c.
>
> Agreed. Let me finish merging the inter_module_xxx() stuff before you do
> that, though.
>
> --
> dwmw2
>
> To unsubscribe, send "unsubscribe mtd" to majordomo@infradead.org

I have a board that needs support for both cfi and jedec flashes.   So,
the approach
I have taken is to use physmap.c with an array of "physmap_info" structures
that describe the window
address, window size, buswidth and number of partitions for each flash.  I
also use a double array of
mtd_partition structures to divide each flash into partitions (making use
of mtdpart.c).   This allows multiple
flashes to be described in one mapping file so the file is really a
description of a particular board.  There is
a probe for a cfi flash  and if that fails, then a probe for a jedec
flash.    This eliminates the use of
CONFIG_MTD_PHYSMAP_START  (and len and buswidth).   Is this in keeping with
the intent
of the map file?

Alice







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Re: JEDEC support broken?

[David Woodhouse]

On Tue, 14 Nov 2000, Alice Hennessy wrote:

> Do you mean to use map->size instead of bank_size (to spread the
> individual start offsets over if there are gaps between chips)

Nope, discard the concept of bank_size altogether. Each chip needs its own
information structure, much like the 'struct flchip' in
include/mtd/flashchip.h, which contains the start offset of the chip in
the map.

It's reasonable to assume that all chips in the array will be the same
size. You have an array of struct flchip (or your equivalent if you don't
want to use struct flchip) and you index into that by dividing by the
individual chip size - and then just address the chip you've selected by
using the start offset listed for it.

> Also,  is spin_lock support going to be added in jedec.c?

It certainly _needs_ doing. Feel free :)

> I have a board that needs support for both cfi and jedec flashes.
> So, the approach I have taken is to use physmap.c with an array of
> "physmap_info" structures that describe the window address, window
> size, buswidth and number of partitions for each flash.
 < ... deletia ... >

> Is this in keeping with the intent of the map file?

Sounds like it. Show us the code though.

-- 
dwmw2




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Re: JEDEC support broken?

[Alice Hennessy]

[-- Attachment #1: Type: text/plain, Size: 1395 bytes --]

David Woodhouse wrote:

> On Tue, 14 Nov 2000, Alice Hennessy wrote:
>
> > Do you mean to use map->size instead of bank_size (to spread the
> > individual start offsets over if there are gaps between chips)
>
> Nope, discard the concept of bank_size altogether. Each chip needs its own
> information structure, much like the 'struct flchip' in
> include/mtd/flashchip.h, which contains the start offset of the chip in
> the map.
>
> It's reasonable to assume that all chips in the array will be the same
> size. You have an array of struct flchip (or your equivalent if you don't
> want to use struct flchip) and you index into that by dividing by the
> individual chip size - and then just address the chip you've selected by
> using the start offset listed for it.
>
> > Also,  is spin_lock support going to be added in jedec.c?
>
> It certainly _needs_ doing. Feel free :)
>
> > I have a board that needs support for both cfi and jedec flashes.
> > So, the approach I have taken is to use physmap.c with an array of
> > "physmap_info" structures that describe the window address, window
> > size, buswidth and number of partitions for each flash.
>  < ... deletia ... >
>
> > Is this in keeping with the intent of the map file?
>
> Sounds like it. Show us the code though.
>
> --
> dwmw2
>
> To unsubscribe, send "unsubscribe mtd" to majordomo@infradead.org

Attached is my physmap.c.

Alice

[-- Attachment #2: physmap.c --]
[-- Type: text/plain, Size: 5034 bytes --]

/*
 * $Id: physmap.c,v 1.3 2000/07/20 14:18:02 dwmw2 Exp $
 *
 * Normal mappings of chips in physical memory
 */

#include <linux/module.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <asm/io.h>
#include <linux/mtd/mtd.h>
#include <linux/mtd/map.h>
#include <linux/mtd/partitions.h>
#include <linux/config.h>

__u8 physmap_read8(struct map_info *map, unsigned long ofs)
{
//	printk("physmap_read8 at %x\n",map->map_priv_1 + ofs);
	return readb(map->map_priv_1 + ofs);
}

__u16 physmap_read16(struct map_info *map, unsigned long ofs)
{
	return readw(map->map_priv_1 + ofs);
}

__u32 physmap_read32(struct map_info *map, unsigned long ofs)
{
	return readl(map->map_priv_1 + ofs);
}

void physmap_copy_from(struct map_info *map, void *to, unsigned long from, ssize_t len)
{
	memcpy_fromio(to, map->map_priv_1 + from, len);
}

void physmap_write8(struct map_info *map, __u8 d, unsigned long adr)
{
//	printk("physmap_write8 %x at %x\n",d,map->map_priv_1 + adr);
	writeb(d, map->map_priv_1 + adr);
}

void physmap_write16(struct map_info *map, __u16 d, unsigned long adr)
{
	writew(d, map->map_priv_1 + adr);
}

void physmap_write32(struct map_info *map, __u32 d, unsigned long adr)
{
	//printk("physmap_write32 %x at %x\n",d,map->map_priv_1 + adr);
	writel(d, map->map_priv_1 + adr);
}

void physmap_copy_to(struct map_info *map, unsigned long to, const void *from, ssize_t len)
{
	memcpy_toio(map->map_priv_1 + to, from, len);
}

void physmap_set_vpp(int vpp)
{
}

const struct map_info basic_physmap_map = {
	NULL,
	0,
	0,
	physmap_read8,
	physmap_read16,
	physmap_read32,
	physmap_copy_from,
	physmap_write8,
	physmap_write16,
	physmap_write32,
	physmap_copy_to,
        physmap_set_vpp,
	0,
	0
};

/* board and partition description */

#define MAX_PHYSMAP_PARTITIONS    8
struct physmap_info {
	char *name;
	unsigned long window_addr;
	unsigned long window_size;
	int buswidth;
	int num_partitions;
};

#define PHYSMAP_NUMBER  2  // number of physmap_info structs needed
const struct physmap_info physmap_board_desc[PHYSMAP_NUMBER] = 
{
    {   // Am29DL323D in 2x16 configuration
        "big flash",     // name
	0x40000000,      // window_addr
	0x00800000,      // window_size
        4,               // buswidth
	2,               // num_partitions
    },
    {   // Am29W040B in 1x8 configuration
        "boot flash",    // name
	0xfff80000,      // window_addr
	0x00060000,      // window_size
        1,               // buswidth
	2,               // num_partitions
    },

};
static struct mtd_partition physmap_partitions[PHYSMAP_NUMBER][MAX_PHYSMAP_PARTITIONS] = {
{  // Am29DL323D in 2x16 configuration
	{
		name: "big flash 128k sectors",
		size: 0x007E0000, // 63 x (2 x 64k) byte sectors
		offset: 0,
	},
	{
		name: "big flash 16k sectors",
		size: 0x00020000, // 8  x (2 x 8k)  byte sectors
		offset: 0x007E0000,
	},
},
{  // Am29W040B in 1x8 configuration  
	{
		name: "boot environment",
		size: 0x00010000, // 1 x 64k byte sectors
		offset: 0
	},
	{
		name: "boot flash sectors",
		size: 0x00050000, // 5 x 64k byte sectors
		offset: 0x10000
	},
}
};

struct map_info physmap_map[PHYSMAP_NUMBER];

int __init init_physmap(void)
{
	int i;
        struct mtd_info *mymtd;
        struct mtd_partition *parts;

	/* Initialize mapping */
	for (i=0;i<PHYSMAP_NUMBER;i++) {
		printk(KERN_NOTICE "physmap flash device: %x at %x\n", (unsigned int)physmap_board_desc[i].window_size, (unsigned int)physmap_board_desc[i].window_addr);
                memcpy((char *)&physmap_map[i],(char *)&basic_physmap_map,sizeof(struct map_info));
		physmap_map[i].map_priv_1 = (unsigned long)ioremap(physmap_board_desc[i].window_addr, physmap_board_desc[i].window_size);
		if (!physmap_map[i].map_priv_1) {
			printk(KERN_WARNING "Failed to ioremap\n");
			return -EIO;
	        }
		physmap_map[i].name = physmap_board_desc[i].name;
		physmap_map[i].size = physmap_board_desc[i].window_size;
		physmap_map[i].buswidth = physmap_board_desc[i].buswidth;
		printk(KERN_NOTICE "physmap: ioremap is %x\n",(unsigned int)(physmap_map[i].map_priv_1));
	}

	for (i=0;i<PHYSMAP_NUMBER;i++) {
                parts = &physmap_partitions[i][0];
		mymtd = do_cfi_probe(&physmap_map[i]);
		if (!mymtd) {
			mymtd = do_jedec_probe(&physmap_map[i]);
		}
		if (mymtd) {
#ifdef MODULE
			mymtd->module = &__this_module;
#endif
			/* save mymtd for cleanup */
	                physmap_map[i].map_priv_2 = (unsigned long)mymtd;
		        add_mtd_partitions(mymtd, parts, physmap_board_desc[i].num_partitions);
		}
		else
	           return -ENXIO;
	}
	return 0;
}

static void __exit cleanup_physmap(void)
{
	int i;
        struct mtd_info *mymtd;

	for (i=0;i<PHYSMAP_NUMBER;i++) {
	        mymtd = (struct mtd_info *)physmap_map[i].map_priv_2;
		if (mymtd) {
			del_mtd_partitions(mymtd);
			map_destroy(mymtd);
		}
		if (physmap_map[i].map_priv_1) {
			iounmap((void *)physmap_map[i].map_priv_1);
			physmap_map[i].map_priv_1 = 0;
		}
	}
}

#if LINUX_VERSION_CODE > 0x20300
module_init(init_physmap);
module_exit(cleanup_physmap);
#endif