region_info_user and otp_info

region_info_user and otp_info

[Anand Patil]

Hi,
       I am new bee to MTD user land,

      1)  Iam not getting what region information refers to in MTD?
            ---------------------------
            struct region_info_user {
            uint32_t offset;                /* At which this region starts,
                                         * from the beginning of the MTD */
            uint32_t erasesize;             /* For this region */
            uint32_t numblocks;             /* Number of blocks in this 
region */
            uint32_t regionindex;
            };
           ---------------------------

    2) I did'nt get the purpose of the below strucuture defined and its 
usage ?
        ---------------------------
        struct otp_info {
                uint32_t start;
                uint32_t length;
                uint32_t locked;
        };

        ---------------------------

Warm Regards,
Anand Patil 

Re: region_info_user and otp_info

[Josh Boyer]

On Tue, 2006-11-07 at 09:20 +0530, Anand Patil wrote:
> Hi,
>        I am new bee to MTD user land,
> 
>       1)  Iam not getting what region information refers to in MTD?

Some chips have multiple erase regions.  These regions can have
eraseblocks of different size than the rest of the chip.  That is what
the structure is reporting.


>     2) I did'nt get the purpose of the below strucuture defined and its 
> usage ?

OTP stands for One Time Programmable.  Some chips have an area that is
only writable once.  It can be used to store serial numbers, or whatever
you'd like to store as long as you only need to write that information a
single time.  That is what this structure is referring to.

josh

Re: region_info_user and otp_info

[Anand Patil]

Josh,
           I got a AMD NOR Flash AM29LV256M,
           It supports a feature called as Secured Silicon Sector (i.e. a 
256 byte region which can be programmed only once)
           To access the above feature a particular command sequence has to 
be issued
            How can I  know whether the above feature is already 
incorporated in the MTD release OR
            else we need to support it at the driver layer?


Warm Regards,
Anand Patil
----- Original Message ----- 
From: "Josh Boyer" <jwboyer@linux.vnet.ibm.com>
To: "Anand Patil" <anandpatil@ti.com>
Cc: <linux-mtd@lists.infradead.org>
Sent: Tuesday, November 07, 2006 5:15 PM
Subject: Re: region_info_user and otp_info


> On Tue, 2006-11-07 at 09:20 +0530, Anand Patil wrote:
>> Hi,
>>        I am new bee to MTD user land,
>>
>>       1)  Iam not getting what region information refers to in MTD?
>
> Some chips have multiple erase regions.  These regions can have
> eraseblocks of different size than the rest of the chip.  That is what
> the structure is reporting.
>
>
>>     2) I did'nt get the purpose of the below strucuture defined and its
>> usage ?
>
> OTP stands for One Time Programmable.  Some chips have an area that is
> only writable once.  It can be used to store serial numbers, or whatever
> you'd like to store as long as you only need to write that information a
> single time.  That is what this structure is referring to.
>
> josh
>
>