[U-Boot] Flash Erase and Write timeout for S29GL512P

[U-Boot] Flash Erase and Write timeout for S29GL512P

[prakash bedge]

Hi All,

I am using 64MB CFI compliant flash on my board. For that I need to
configure the erase and write timeout for this chip in configs/boardname.h
file

Flash chip I am using is S29GL512P and as per datasheet flash erase time is
1024 Seconds and flash program time is 492 Seconds.

So  CONFIG_SYS_FLASH_ERASE_TOUT   should be 1024000 ms and
CONFIG_SYS_FLASH_WRITE_TOUT
should be 492000 ms.

 But, in Uboot, I am seeing that most boards have  configured
CONFIG_SYS_FLASH_ERASE_TOUT
to 240000 ms and  CONFIG_SYS_FLASH_WRITE_TOUT   to 200-400 ms range for
flash of size 1GB or moroe.

Can anyone please tell what value I should use for my chip.

Regards,
Prakash

[U-Boot] Flash Erase and Write timeout for S29GL512P

[Wolfgang Denk]

Dear prakash bedge,

In message <AANLkTil9bEkSR6MOcuCbgkxhJN-VKKdOAEMnHIYjqNVj@mail.gmail.com> you wrote:
>
> Flash chip I am using is S29GL512P and as per datasheet flash erase time is
> 1024 Seconds and flash program time is 492 Seconds.

Be careful. 1024 s is chip erase time, but we use sector erase only,
so it's only 3.5 seconds.

Same for the 492 s - this is Chip Program Time which does not matter
here.

>  But, in Uboot, I am seeing that most boards have  configured
> CONFIG_SYS_FLASH_ERASE_TOUT
> to 240000 ms and  CONFIG_SYS_FLASH_WRITE_TOUT   to 200-400 ms range for
> flash of size 1GB or moroe.
> 
> Can anyone please tell what value I should use for my chip.

The CFI driver accesses the flash in sectors only, so sector times
apply, not chip times.

Best regards,

Wolfgang Denk

-- 
DENX Software Engineering GmbH,     MD: Wolfgang Denk & Detlev Zundel
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
Even if you aren't in doubt, consider the mental welfare of the  per-
son who has to maintain the code after you, and who will probably put
parens in the wrong place.          - Larry Wall in the perl man page

[U-Boot] Flash Erase and Write timeout for S29GL512P

[prakash bedge]

Hi,

>> Be careful. 1024 s is chip erase time, but we use sector erase only, so
it's only 3.5 seconds.
It would be really helpful if you please explain how 3.5 seconds come; since
the S29GL512P datasheet says sector erase operation time is 0.5 seconds and
program operation time is 64 microseconds.

 What values I should put in my config file?
#define CONFIG_SYS_FLASH_ERASE_TOUT ??  /* Timeout for Flash Erase (in
ms) */
#define CONFIG_SYS_FLASH_WRITE_TOUT ?? /* Timeout for Flash Write (in ms) */

I seen canyonlands.h and I think it is also 64 MB flash.

/*-----------------------------------------------------------------------
 * FLASH related
 *----------------------------------------------------------------------*/
#define CONFIG_SYS_FLASH_CFI   /* The flash is CFI compatible */
#define CONFIG_FLASH_CFI_DRIVER  /* Use common CFI driver */

#define CONFIG_SYS_FLASH_CFI_AMD_RESET 1 /* Use AMD (Spansion) reset cmd */
#define CONFIG_SYS_FLASH_BANKS_LIST    {CONFIG_SYS_FLASH_BASE}
#define CONFIG_SYS_MAX_FLASH_BANKS 1 /* max number of memory banks  */
#define CONFIG_SYS_MAX_FLASH_SECT 512 /* max number of sectors on one
chip */


#define CONFIG_SYS_FLASH_ERASE_TOUT 120000 /* Timeout for Flash Erase (in
ms) */
#define CONFIG_SYS_FLASH_WRITE_TOUT 500 /* Timeout for Flash Write (in
ms) */

But I myself is not geting satsifed why I should use these values since they
are not as per the flash datasheet.


Regards,
Prakash




On Fri, May 21, 2010 at 12:46 PM, Wolfgang Denk <wd@denx.de> wrote:

> Dear prakash bedge,
>
> In message <AANLkTil9bEkSR6MOcuCbgkxhJN-VKKdOAEMnHIYjqNVj@mail.gmail.com>
> you wrote:
> >
> > Flash chip I am using is S29GL512P and as per datasheet flash erase time
> is
> > 1024 Seconds and flash program time is 492 Seconds.
>
> Be careful. 1024 s is chip erase time, but we use sector erase only,
> so it's only 3.5 seconds.
>
> Same for the 492 s - this is Chip Program Time which does not matter
> here.
>
> >  But, in Uboot, I am seeing that most boards have  configured
> > CONFIG_SYS_FLASH_ERASE_TOUT
> > to 240000 ms and  CONFIG_SYS_FLASH_WRITE_TOUT   to 200-400 ms range for
> > flash of size 1GB or moroe.
> >
> > Can anyone please tell what value I should use for my chip.
>
> The CFI driver accesses the flash in sectors only, so sector times
> apply, not chip times.
>
> Best regards,
>
> Wolfgang Denk
>
> --
> DENX Software Engineering GmbH,     MD: Wolfgang Denk & Detlev Zundel
> HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
> Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
> Even if you aren't in doubt, consider the mental welfare of the  per-
> son who has to maintain the code after you, and who will probably put
> parens in the wrong place.          - Larry Wall in the perl man page
>

[U-Boot] Flash Erase and Write timeout for S29GL512P

[Andreas Bießmann]

Hi,

Am 25.05.2010 10:31, schrieb prakash bedge:
> Hi,
> 
>>> Be careful. 1024 s is chip erase time, but we use sector erase only, so
> it's only 3.5 seconds.
> It would be really helpful if you please explain how 3.5 seconds come; since
> the S29GL512P datasheet says sector erase operation time is 0.5 seconds and
> program operation time is 64 microseconds.

Please see Datasheet 11.7.5: Sector Erase Time Typ = 0.5; max = 3.5 Unit
= sec

regards

Andreas Bie?mann

[U-Boot] Flash Erase and Write timeout for S29GL512P

[Wolfgang Denk]

Dear prakash bedge,

In message <AANLkTilsrQ2jt8A2d9Lczd1uJHRa_3BcofQOjphinnyT@mail.gmail.com> you wrote:
>
> >> Be careful. 1024 s is chip erase time, but we use sector erase only, so
> it's only 3.5 seconds.
> It would be really helpful if you please explain how 3.5 seconds come; since
> the S29GL512P datasheet says sector erase operation time is 0.5 seconds and
> program operation time is 64 microseconds.

The data sheet "S29GL-P MirrorBit? Flash Family" (see
http://www.spansion.com/Support/Datasheets/S29GL-P_00_A12_e.pdf) reads
in "Table 11.8 Erase And Programming Performance" (page 67):

Parameter		Typ	Max	Unit	Comments
Sector Erase Time	0.5	3.5	sec

So the 0.5 seconds you are referring to is the "Typical program and
erase times assume the following conditions: 25?C, 3.6 V VCC, 10,000
cycles, checkerboard pattern."

The 3.5 seconds I listed was " Under worst case conditions of -40?C,
VCC = 3.0 V, 100,000 cycles."

Obviously it is necessary to adjust this timeout for worst case
conditions.

>  What values I should put in my config file?
> #define CONFIG_SYS_FLASH_ERASE_TOUT ??  /* Timeout for Flash Erase (in
> ms) */

I would use 5000 here (i. e. 5 seconds, which is 3.5 plus some safety
margin).

> #define CONFIG_SYS_FLASH_WRITE_TOUT ?? /* Timeout for Flash Write (in ms) */

Here we have to calculate the timing based on the  Write Buffer
Programming Time.

> I seen canyonlands.h and I think it is also 64 MB flash.
...
> #define CONFIG_SYS_FLASH_ERASE_TOUT 120000 /* Timeout for Flash Erase (in
> ms) */
> #define CONFIG_SYS_FLASH_WRITE_TOUT 500 /* Timeout for Flash Write (in
> ms) */

So - did you try using these values? And did they not work for you?

> But I myself is not geting satsifed why I should use these values since they
> are not as per the flash datasheet.

They are timeouts, and they are most ptobably defensively set.


I don't understand your problem. Keep in mind that these timeouts
don't play any role as long as the chip is working normally - they
apply only in the error case. And if your flash chip cannot be erased
or programmed any more it does not really matter if you find out
after 3.5 or after 5 or even after 12 seconds - you will lose much
more time after that ;-)

Best regards,

Wolfgang Denk

-- 
DENX Software Engineering GmbH,     MD: Wolfgang Denk & Detlev Zundel
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
Death. Destruction. Disease. Horror. That's what war  is  all  about.
That's what makes it a thing to be avoided.
	-- Kirk, "A Taste of Armageddon", stardate 3193.0

[U-Boot] Flash Erase and Write timeout for S29GL512P

[prakash bedge]

Hi,

I got the answers.

It was my negligence to miss the table. Sorry for taking your time.:)

Thanks & regards,
Prakash Bedge
On Tue, May 25, 2010 at 5:11 PM, Wolfgang Denk <wd@denx.de> wrote:

> Dear prakash bedge,
>
> In message <AANLkTilsrQ2jt8A2d9Lczd1uJHRa_3BcofQOjphinnyT@mail.gmail.com>
> you wrote:
> >
> > >> Be careful. 1024 s is chip erase time, but we use sector erase only,
> so
> > it's only 3.5 seconds.
> > It would be really helpful if you please explain how 3.5 seconds come;
> since
> > the S29GL512P datasheet says sector erase operation time is 0.5 seconds
> and
> > program operation time is 64 microseconds.
>
> The data sheet "S29GL-P MirrorBit? Flash Family" (see
> http://www.spansion.com/Support/Datasheets/S29GL-P_00_A12_e.pdf) reads
> in "Table 11.8 Erase And Programming Performance" (page 67):
>
> Parameter               Typ     Max     Unit    Comments
> Sector Erase Time       0.5     3.5     sec
>
> So the 0.5 seconds you are referring to is the "Typical program and
> erase times assume the following conditions: 25?C, 3.6 V VCC, 10,000
> cycles, checkerboard pattern."
>
> The 3.5 seconds I listed was " Under worst case conditions of -40?C,
> VCC = 3.0 V, 100,000 cycles."
>
> Obviously it is necessary to adjust this timeout for worst case
> conditions.
>
> >  What values I should put in my config file?
> > #define CONFIG_SYS_FLASH_ERASE_TOUT ??  /* Timeout for Flash Erase (in
> > ms) */
>
> I would use 5000 here (i. e. 5 seconds, which is 3.5 plus some safety
> margin).
>
> > #define CONFIG_SYS_FLASH_WRITE_TOUT ?? /* Timeout for Flash Write (in ms)
> */
>
> Here we have to calculate the timing based on the  Write Buffer
> Programming Time.
>
> > I seen canyonlands.h and I think it is also 64 MB flash.
> ...
> > #define CONFIG_SYS_FLASH_ERASE_TOUT 120000 /* Timeout for Flash Erase (in
> > ms) */
> > #define CONFIG_SYS_FLASH_WRITE_TOUT 500 /* Timeout for Flash Write (in
> > ms) */
>
> So - did you try using these values? And did they not work for you?
>
> > But I myself is not geting satsifed why I should use these values since
> they
> > are not as per the flash datasheet.
>
> They are timeouts, and they are most ptobably defensively set.
>
>
> I don't understand your problem. Keep in mind that these timeouts
> don't play any role as long as the chip is working normally - they
> apply only in the error case. And if your flash chip cannot be erased
> or programmed any more it does not really matter if you find out
> after 3.5 or after 5 or even after 12 seconds - you will lose much
> more time after that ;-)
>
> Best regards,
>
> Wolfgang Denk
>
> --
> DENX Software Engineering GmbH,     MD: Wolfgang Denk & Detlev Zundel
> HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
> Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
> Death. Destruction. Disease. Horror. That's what war  is  all  about.
> That's what makes it a thing to be avoided.
>        -- Kirk, "A Taste of Armageddon", stardate 3193.0
>