Boot Block and Uniform Block Flash Memory and Executin In Place(XIP) - Embedded

This is a discussion on Boot Block and Uniform Block Flash Memory and Executin In Place(XIP) - Embedded ; Hi, I understand that boot block Flash Memory have "protected boot blocks" so they can not be erased accidentally unless special functions are used to do that. Further, Top Boot Block Flash memory are intended for microprocessors that begin execution ...

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Thread: Boot Block and Uniform Block Flash Memory and Executin In Place(XIP)

  1. Boot Block and Uniform Block Flash Memory and Executin In Place(XIP)

    Hi,

    I understand that boot block Flash Memory have "protected boot blocks"
    so they can not be erased accidentally unless special functions are
    used to do that.

    Further, Top Boot Block Flash memory are intended for microprocessors
    that begin
    execution by reading from the top of their memory space. And vice
    versa for Bottom
    Boot Bloc Flash Memory. Here, the Boot Block is positioned at the
    bottom of the
    Flash's address space for many microprocessors that have their Reset
    vector at 0000h.
    So, my mapping the Flash to address 0000h of the processor's address
    space, the
    processor can boot from the Flash's Boot Block.

    I find that some some major processor makers use Bottom Boot(ST10,
    Motorola 68000 series, Power PC) and others use Top Boot(Intel i960,
    80x86 ).

    My Queries are :-
    1) But, What is the advantage of Top Boot Flash Memory and
    What is the advantage of Bottom Boot Flash memory ?

    2) Apart from protection to the Boot Block, what are the other
    differences between
    these Boot Block based Flash memories and Normal Flash Memories
    (Uniform
    Block Flash Memory)?

    3) Which is cost-effective (Boot Block based Flash or Normal Flash
    ( Uniform Block
    Flash Memory) ) ?

    4) Is the lifetime (Number of programmable / erase cycles) of the Boot
    Block lesser
    than or equivalent to that of the Normal Blocks (Application Code,
    User
    Parameters and User Data.) ?

    5) Can that Boot Block area used for other purporses w.r.t security of
    the application ?

    6) I understand that for systems with small amounts of memory, XIP is
    very good that
    each instance of that program uses system RAM, only for their
    stack, BSS, and
    data segments while the shared text segment remains in Flash
    Memory.
    But, Is there any specific Block for text segment while
    performing XIP ?

    7) Is there any other specific configuration to look for while
    selecting the Flash
    Memory while going in for XIP ?

    Thx in advans,
    Karthik Balaguru


  2. Re: Boot Block and Uniform Block Flash Memory and Executin In Place(XIP)

    Hi,

    Re-posting it as it was misaligned in the firs post.

    I understand that boot block Flash Memory have "protected
    boot blocks" so they can not be erased accidentally unless
    special functions are used to do that.

    Further, Top Boot Block Flash memory are intended for
    microprocessors that begin execution by reading from the top
    of their memory space. And vice versa for Bottom Boot Block
    Flash Memory. Here, the Boot Block is positioned at the bottom
    of the Flash's address space for many microprocessors that
    have their Reset vector at 0000h. So, my mapping the Flash to
    address 0000h of the processor's address space, the processor
    can boot from the Flash's Boot Block.

    I find that some some major processor makers use Bottom
    Boot(ST10, Motorola 68000 series, Power PC) and others use
    Top Boot(Intel i960, 80x86 ).

    My Queries are :-
    1) But, What is the advantage of Top Boot Flash Memory and
    What is the advantage of Bottom Boot Flash memory ?

    2) Apart from protection to the Boot Block, what are the other
    differences between these Boot Block based Flash memories
    and Normal Flash Memories (Uniform Block Flash Memory)?

    3) Which is cost-effective (Boot Block based Flash or Normal
    Flash ( Uniform Block Flash Memory) ) ?

    4) Is the lifetime (Number of programmable / erase cycles)
    of the Boot Block lesser than or equivalent to that of
    the Normal Blocks (Application Code, User
    Parameters and User Data)?

    5) Can that Boot Block area used for other purporses w.r.t
    security of the application ?

    6) I understand that for systems with small amounts of memory,
    XIP is very good that each instance of that program uses
    system RAM, only for their stack, BSS, and data segments
    while the shared text segment remains in Flash Memory.

    But, Is there any specific Block dedicated for text segment
    while performing XIP in either Boot Block Flash Memories
    or Uniform Block Flash Memories(Normal Flash Memories)?

    7) Is there any other specific configuration to look for while
    selecting the Flash Memory while going in for XIP ?

    Thx in advans,
    Karthik Balaguru


  3. Re: Boot Block and Uniform Block Flash Memory and Executin In Place(XIP)

    Hi,

    karthikbalaguru wrote:
    > My Queries are :-
    > 1) But, What is the advantage of Top Boot Flash Memory and
    > What is the advantage of Bottom Boot Flash memory ?


    Sometimes these special blocks are smaller than the others. This might be an
    advantage, when you have to store some kind of variable information in it.
    You waste less space in this case (the bootloader u-boot does so. Sometimes
    you must waste 256kiB (one sector), but you only need 3kiB for the real
    data).

    > 2) Apart from protection to the Boot Block, what are the other
    > differences between these Boot Block based Flash memories
    > and Normal Flash Memories (Uniform Block Flash Memory)?


    AFAIK no other difference.

    > 3) Which is cost-effective (Boot Block based Flash or Normal
    > Flash ( Uniform Block Flash Memory) ) ?


    Prepare your hardware and software to handle both types. Then you can always
    buy the cheaper one.

    > 4) Is the lifetime (Number of programmable / erase cycles)
    > of the Boot Block lesser than or equivalent to that of
    > the Normal Blocks (Application Code, User
    > Parameters and User Data)?


    AFAIK no.

    > 5) Can that Boot Block area used for other purporses w.r.t
    > security of the application ?


    To store data the user can setup at runtime.

    > 6) I understand that for systems with small amounts of memory,
    > XIP is very good that each instance of that program uses
    > system RAM, only for their stack, BSS, and data segments
    > while the shared text segment remains in Flash Memory.
    >
    > But, Is there any specific Block dedicated for text segment
    > while performing XIP in either Boot Block Flash Memories
    > or Uniform Block Flash Memories(Normal Flash Memories)?


    The sizes of the sectors are only important, when you are going to erase
    them (or when you want to run a real filesystem on top of it, like JFFS2).
    When you read this memory type (=run code from it), they are unimportant.

    Hope it helps
    Juergen

  4. Re: Boot Block and Uniform Block Flash Memory and Executin In Place(XIP)

    I have the following queries based on the Flash Memory.

    1) What is the advantage of Top Boot Flash Memory and
    What is the advantage of Bottom Boot Flash memory ?

    2) Apart from protection to the Boot Block, what are the other
    differences between these Boot Block based Flash memories
    and Normal Flash Memories (Uniform Block Flash Memory)?

    3) Which is cost-effective (Boot Block based Flash or Normal
    Flash ( Uniform Block Flash Memory) ) ?

    4) Is the lifetime (Number of programmable / erase cycles)
    of the Boot Block lesser than or equivalent to that of
    the Normal Blocks (Application Code, User
    Parameters and User Data)?

    5) Can that Boot Block area used for other purporses w.r.t
    security of the application ?

    6) I understand that for systems with small amounts of memory,
    XIP is very good that each instance of that program uses
    system RAM, only for their stack, BSS, and data segments
    while the shared text segment remains in Flash Memory.

    But, Is there any specific Block dedicated for text segment
    while performing XIP in either Boot Block Flash Memories
    or Uniform Block Flash Memories(Normal Flash Memories)?

    7) Is there any other specific configuration to look for while
    selecting the Flash Memory while going in for XIP ?

    Any ideas / link / pdf ?

    Thx in advans,
    Karthik Balaguru


  5. Re: Boot Block and Uniform Block Flash Memory and Executin In Place(XIP)

    On Oct 27, 4:40 pm, karthikbalaguru
    wrote:
    > I have the following queries based on the Flash Memory.
    >
    > 1) What is the advantage of Top Boot Flash Memory and
    > What is the advantage of Bottom Boot Flash memory ?
    >
    > 2) Apart from protection to the Boot Block, what are the other
    > differences between these Boot Block based Flash memories
    > and Normal Flash Memories (Uniform Block Flash Memory)?
    >
    > 3) Which is cost-effective (Boot Block based Flash or Normal
    > Flash ( Uniform Block Flash Memory) ) ?
    >
    > 4) Is the lifetime (Number of programmable / erase cycles)
    > of the Boot Block lesser than or equivalent to that of
    > the Normal Blocks (Application Code, User
    > Parameters and User Data)?
    >
    > 5) Can that Boot Block area used for other purporses w.r.t
    > security of the application ?
    >
    > 6) I understand that for systems with small amounts of memory,
    > XIP is very good that each instance of that program uses
    > system RAM, only for their stack, BSS, and data segments
    > while the shared text segment remains in Flash Memory.
    >
    > But, Is there any specific Block dedicated for text segment
    > while performing XIP in either Boot Block Flash Memories
    > or Uniform Block Flash Memories(Normal Flash Memories)?
    >
    > 7) Is there any other specific configuration to look for while
    > selecting the Flash Memory while going in for XIP ?
    >
    > Any ideas / link / pdf ?
    >


    I posted it 3 days back , but did not get any answers.
    Any problem in the post ?
    Is there any pdf / some links that discusses about these ?

    Thx in advans,
    Karthik Balaguru


  6. Re: Boot Block and Uniform Block Flash Memory and Executin In Place(XIP)

    karthikbalaguru wrote:
    > On Oct 27, 4:40 pm, karthikbalaguru
    > wrote:
    >
    >>I have the following queries based on the Flash Memory.
    >>
    >> 1) What is the advantage of Top Boot Flash Memory and
    >> What is the advantage of Bottom Boot Flash memory ?
    >>
    >> 2) Apart from protection to the Boot Block, what are the other
    >> differences between these Boot Block based Flash memories
    >> and Normal Flash Memories (Uniform Block Flash Memory)?
    >>
    >> 3) Which is cost-effective (Boot Block based Flash or Normal
    >> Flash ( Uniform Block Flash Memory) ) ?
    >>
    >> 4) Is the lifetime (Number of programmable / erase cycles)
    >> of the Boot Block lesser than or equivalent to that of
    >> the Normal Blocks (Application Code, User
    >> Parameters and User Data)?
    >>
    >> 5) Can that Boot Block area used for other purporses w.r.t
    >> security of the application ?
    >>
    >> 6) I understand that for systems with small amounts of memory,
    >> XIP is very good that each instance of that program uses
    >> system RAM, only for their stack, BSS, and data segments
    >> while the shared text segment remains in Flash Memory.
    >>
    >> But, Is there any specific Block dedicated for text segment
    >> while performing XIP in either Boot Block Flash Memories
    >> or Uniform Block Flash Memories(Normal Flash Memories)?
    >>
    >> 7) Is there any other specific configuration to look for while
    >> selecting the Flash Memory while going in for XIP ?
    >>
    >>Any ideas / link / pdf ?
    >>

    >
    >
    > I posted it 3 days back , but did not get any answers.
    > Any problem in the post ?
    > Is there any pdf / some links that discusses about these ?
    >
    > Thx in advans,
    > Karthik Balaguru
    >

    The problem is that you need to do you own home work / research.

    Gmail account are ingorded here.

    sorry,

    ( no I'm not )

  7. Re: Boot Block and Uniform Block Flash Memory and Executin In Place(XIP)

    donald wrote:
    > karthikbalaguru wrote:
    >

    .... snip ...
    >
    >> I posted it 3 days back , but did not get any answers.
    >> Any problem in the post ?
    >> Is there any pdf / some links that discusses about these ?

    >
    > The problem is that you need to do you own home work / research.
    >
    > Gmail account are ingorded here.


    I think he means plonked. In addition, the excessive cross-posting
    without setting follow-ups is also likely to trigger various
    blocks.

    The cure - post to one newsgroup, and get a real news-reader.

    --
    Chuck F (cbfalconer at maineline dot net)
    Available for consulting/temporary embedded and systems.




    --
    Posted via a free Usenet account from http://www.teranews.com


  8. Re: Boot Block and Uniform Block Flash Memory and Executin In Place(XIP)

    On Oct 27, 10:04 pm, CBFalconer wrote:
    > donald wrote:
    > > karthikbalaguru wrote:

    >
    > ... snip ...
    >
    > >> I posted it 3 days back , but did not get any answers.
    > >> Any problem in the post ?
    > >> Is there any pdf / some links that discusses about these ?

    >
    > > The problem is that you need to do you own home work / research.

    >
    > > Gmail account are ingorded here.

    >
    > I think he means plonked. In addition, the excessive cross-posting
    > without setting follow-ups is also likely to trigger various
    > blocks.
    >
    > The cure - post to one newsgroup, and get a real news-reader.
    >


    Ok, Thx for that information

    Karthik Balaguru


  9. Re: Boot Block and Uniform Block Flash Memory and Executin In Place(XIP)

    On Oct 27, 7:46 pm, karthikbalaguru
    wrote:
    > On Oct 27, 4:40 pm, karthikbalaguru
    > wrote:
    >
    >
    >
    > > I have the following queries based on the Flash Memory.

    >
    > > 1) What is the advantage of Top Boot Flash Memory and
    > > What is the advantage of Bottom Boot Flash memory ?

    >
    > > 2) Apart from protection to the Boot Block, what are the other
    > > differences between these Boot Block based Flash memories
    > > and Normal Flash Memories (Uniform Block Flash Memory)?

    >
    > > 3) Which is cost-effective (Boot Block based Flash or Normal
    > > Flash ( Uniform Block Flash Memory) ) ?

    >
    > > 4) Is the lifetime (Number of programmable / erase cycles)
    > > of the Boot Block lesser than or equivalent to that of
    > > the Normal Blocks (Application Code, User
    > > Parameters and User Data)?

    >
    > > 5) Can that Boot Block area used for other purporses w.r.t
    > > security of the application ?

    >
    > > 6) I understand that for systems with small amounts of memory,
    > > XIP is very good that each instance of that program uses
    > > system RAM, only for their stack, BSS, and data segments
    > > while the shared text segment remains in Flash Memory.

    >
    > > But, Is there any specific Block dedicated for text segment
    > > while performing XIP in either Boot Block Flash Memories
    > > or Uniform Block Flash Memories(Normal Flash Memories)?

    >
    > > 7) Is there any other specific configuration to look for while
    > > selecting the Flash Memory while going in for XIP ?

    >
    > > Any ideas / link / pdf ?

    >
    > I posted it 3 days back , but did not get any answers.
    > Any problem in the post ?
    > Is there any pdf / some links that discusses about these ?
    >
    > Thx in advans,
    > Karthik Balaguru


    --snip--
    > Any problem in the post ?

    Yes, too many questions marks.

    > Is there any pdf / some links that discusses about these ?


    I would suggest Adobe.


    ali


  10. Re: Boot Block and Uniform Block Flash Memory and Executin In Place(XIP)

    CBFalconer wrote:
    > donald wrote:
    >> karthikbalaguru wrote:
    >>

    > ... snip ...
    >>> I posted it 3 days back , but did not get any answers.
    >>> Any problem in the post ?
    >>> Is there any pdf / some links that discusses about these ?

    >> The problem is that you need to do you own home work / research.
    >>
    >> Gmail account are ingorded here.

    >
    > I think he means plonked. In addition, the excessive cross-posting
    > without setting follow-ups is also likely to trigger various
    > blocks.
    >
    > The cure - post to one newsgroup, and get a real news-reader.


    Is someone confusing gmail with google groups? I see nothing wrong with
    either. I use groups.google.com when I'm away from home, and a gmail
    account isn't fundamentally different from AOL or Yahoo. I think
    Google's spam policies are deplorable and I agree than they're home to
    trolls and the clueless, but son't blame the service for the foibles of
    its users. IIRC, Rune Alnor uses gmail. Whoever ignores him loses much.

    karthikbalaguru: I ignored your question because I had no answer. Maybe
    I'm not alone in that.

    Jerry
    --
    Engineering is the art of making what you want from things you can get.
    ŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻ ŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻ

  11. Re: Boot Block and Uniform Block Flash Memory and Executin In Place(XIP)

    On Oct 28, 2:31 am, Jerry Avins wrote:
    > CBFalconer wrote:
    > > donald wrote:
    > >> karthikbalaguru wrote:

    >
    > > ... snip ...
    > >>> I posted it 3 days back , but did not get any answers.
    > >>> Any problem in the post ?
    > >>> Is there any pdf / some links that discusses about these ?
    > >> The problem is that you need to do you own home work / research.

    >
    > >> Gmail account are ingorded here.

    >
    > > I think he means plonked. In addition, the excessive cross-posting
    > > without setting follow-ups is also likely to trigger various
    > > blocks.

    >
    > > The cure - post to one newsgroup, and get a real news-reader.

    >
    > Is someone confusing gmail with google groups? I see nothing wrong with
    > either. I use groups.google.com when I'm away from home, and a gmail
    > account isn't fundamentally different from AOL or Yahoo. I think
    > Google's spam policies are deplorable and I agree than they're home to
    > trolls and the clueless, but son't blame the service for the foibles of
    > its users. IIRC, Rune Alnor uses gmail. Whoever ignores him loses much.
    >
    > karthikbalaguru: I ignored your question because I had no answer. Maybe
    > I'm not alone in that.
    >
    > Jerry
    > --
    > Engineering is the art of making what you want from things you can get.
    > ŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻ ŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻ



    --snip--
    > Is someone confusing gmail with google groups? I see nothing wrong with
    > either. I use groups.google.com when I'm away from home, and a gmail
    > account isn't fundamentally different from AOL or Yahoo.


    So do I!

    Actually while ago i tried to switch to some _dedicated_ software to
    access the usenet (a.k.a news reader). But yoiu know I ened up with
    nothing. Because google.groups does provide you lots of goodies that
    ANY standard reader is simply unable to provide. Unless you have *
    huge storage and enough processing to store and archive the things
    that might happen anywhere at anytime.

    I'm telling you its super easy to search the discussions and day to
    day issuse via google's interface (google groups). Sure, news readers
    are fine if you are focusing defined domains and don't have dynamic
    areas to explore.


    ali



  12. Re: Boot Block and Uniform Block Flash Memory and Executin In Place(XIP)

    Jerry Avins wrote:
    > CBFalconer wrote:
    >> donald wrote:
    >>> karthikbalaguru wrote:
    >>>

    >> ... snip ...
    >>>
    >>>> I posted it 3 days back , but did not get any answers.
    >>>> Any problem in the post ?
    >>>> Is there any pdf / some links that discusses about these ?
    >>>
    >>> The problem is that you need to do you own home work / research.
    >>>
    >>> Gmail account are ingorded here.

    >>
    >> I think he means plonked. In addition, the excessive cross-posting
    >> without setting follow-ups is also likely to trigger various
    >> blocks.
    >>
    >> The cure - post to one newsgroup, and get a real news-reader.

    >
    > Is someone confusing gmail with google groups? I see nothing wrong
    > with either. I use groups.google.com when I'm away from home, and
    > a gmail account isn't fundamentally different from AOL or Yahoo. I
    > think Google's spam policies are deplorable and I agree than
    > they're home to trolls and the clueless, but son't blame the
    > service for the foibles of its users. IIRC, Rune Alnor uses gmail.
    > Whoever ignores him loses much.


    I was not criticizing him, just pointing out the effects he is
    causing. He is posting through google groups - see the
    Organization header.

    --
    Chuck F (cbfalconer at maineline dot net)
    Available for consulting/temporary embedded and systems.




    --
    Posted via a free Usenet account from http://www.teranews.com


  13. Re: Boot Block and Uniform Block Flash Memory and Executin In Place(XIP)

    CBFalconer wrote:

    ...

    > I was not criticizing him, just pointing out the effects he is
    > causing. He is posting through google groups - see the
    > Organization header.


    Many of us do some of the time. McLuhan to the contrary, it's not the
    medium and the message aren't one and the same. the message.

    Jerry
    --
    Engineering is the art of making what you want from things you can get.
    ŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻ ŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻ

  14. Re: Boot Block and Uniform Block Flash Memory and Executin In Place(XIP)

    Jerry Avins wrote:
    > CBFalconer wrote:
    >
    > ...
    >
    >> I was not criticizing him, just pointing out the effects he is
    >> causing. He is posting through google groups - see the
    >> Organization header.

    >
    > Many of us do some of the time. McLuhan to the contrary, it's not the
    > medium and the message aren't one and the same. the message.


    Eh? That's not what I wrote. I wrote

    McLuhan to the contrary, the medium and the message aren't one and the
    same.

    Jerry
    --
    Engineering is the art of making what you want from things you can get.
    ŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻ ŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻŻ

  15. Re: Boot Block and Uniform Block Flash Memory and Executin In Place(XIP)

    On Oct 27, 11:31 pm, Jerry Avins wrote:
    > CBFalconer wrote:
    > > donald wrote:
    > >> karthikbalaguru wrote:

    >
    > > ... snip ...
    > >>> I posted it 3 days back , but did not get any answers.
    > >>> Any problem in the post ?
    > >>> Is there any pdf / some links that discusses about these ?
    > >> The problem is that you need to do you own home work / research.

    >
    > >> Gmail account are ingorded here.

    >
    > > I think he means plonked. In addition, the excessive cross-posting
    > > without setting follow-ups is also likely to trigger various
    > > blocks.

    >
    > > The cure - post to one newsgroup, and get a real news-reader.

    >
    > Is someone confusing gmail with google groups? I see nothing wrong with
    > either. I use groups.google.com when I'm away from home, and a gmail
    > account isn't fundamentally different from AOL or Yahoo. I think
    > Google's spam policies are deplorable and I agree than they're home to
    > trolls and the clueless, but son't blame the service for the foibles of
    > its users. IIRC, Rune Alnor uses gmail. Whoever ignores him loses much.
    >
    > karthikbalaguru: I ignored your question because I had no answer. Maybe
    > I'm not alone in that.
    >


    Ok, Thx for the information .

    Karthik Balaguru


  16. Re: Boot Block and Uniform Block Flash Memory and Executin In Place(XIP)

    On Oct 27, 11:31 pm, Jerry Avins wrote:
    > CBFalconer wrote:
    > > donald wrote:
    > >> karthikbalaguru wrote:

    >
    > > ... snip ...
    > >>> I posted it 3 days back , but did not get any answers.
    > >>> Any problem in the post ?
    > >>> Is there any pdf / some links that discusses about these ?
    > >> The problem is that you need to do you own home work / research.

    >
    > >> Gmail account are ingorded here.

    >
    > > I think he means plonked. In addition, the excessive cross-posting
    > > without setting follow-ups is also likely to trigger various
    > > blocks.

    >
    > > The cure - post to one newsgroup, and get a real news-reader.

    >
    > Is someone confusing gmail with google groups? I see nothing wrong with
    > either. I use groups.google.com when I'm away from home, and a gmail
    > account isn't fundamentally different from AOL or Yahoo. I think
    > Google's spam policies are deplorable and I agree than they're home to
    > trolls and the clueless, but son't blame the service for the foibles of
    > its users. IIRC, Rune Alnor uses gmail. Whoever ignores him loses much.
    >
    > karthikbalaguru: I ignored your question because I had no answer. Maybe
    > I'm not alone in that.
    >


    Ok, Thx of that information.

    Karthik Balaguru


  17. Re: Boot Block and Uniform Block Flash Memory and Executin In Place(XIP)

    karthikbalaguru wrote:
    > I have the following queries based on the Flash Memory.
    >
    > 1) What is the advantage of Top Boot Flash Memory and
    > What is the advantage of Bottom Boot Flash memory ?
    >
    > 2) Apart from protection to the Boot Block, what are the other
    > differences between these Boot Block based Flash memories
    > and Normal Flash Memories (Uniform Block Flash Memory)?
    >
    > 3) Which is cost-effective (Boot Block based Flash or Normal
    > Flash ( Uniform Block Flash Memory) ) ?
    >
    > 4) Is the lifetime (Number of programmable / erase cycles)
    > of the Boot Block lesser than or equivalent to that of
    > the Normal Blocks (Application Code, User
    > Parameters and User Data)?
    >
    > 5) Can that Boot Block area used for other purporses w.r.t
    > security of the application ?
    >
    > 6) I understand that for systems with small amounts of memory,
    > XIP is very good that each instance of that program uses
    > system RAM, only for their stack, BSS, and data segments
    > while the shared text segment remains in Flash Memory.
    >
    > But, Is there any specific Block dedicated for text segment
    > while performing XIP in either Boot Block Flash Memories
    > or Uniform Block Flash Memories(Normal Flash Memories)?
    >
    > 7) Is there any other specific configuration to look for while
    > selecting the Flash Memory while going in for XIP ?
    >
    > Any ideas / link / pdf ?
    >
    > Thx in advans,
    > Karthik Balaguru
    >




    Did you already see the "Uniform versus boot block Flash architectures"
    document from STMicroelectronics.
    you can find it here:
    http://www.st.com/stonline/products/...re/an/7105.pdf

    ---
    NvB

  18. Re: Boot Block and Uniform Block Flash Memory and Executin In Place(XIP)

    On Nov 1, 2:16 pm, Norbert van Bolhuis wrote:
    > karthikbalaguru wrote:
    > > I have the following queries based on the Flash Memory.

    >
    > > 1) What is the advantage of Top Boot Flash Memory and
    > > What is the advantage of Bottom Boot Flash memory ?

    >
    > > 2) Apart from protection to the Boot Block, what are the other
    > > differences between these Boot Block based Flash memories
    > > and Normal Flash Memories (Uniform Block Flash Memory)?

    >
    > > 3) Which is cost-effective (Boot Block based Flash or Normal
    > > Flash ( Uniform Block Flash Memory) ) ?

    >
    > > 4) Is the lifetime (Number of programmable / erase cycles)
    > > of the Boot Block lesser than or equivalent to that of
    > > the Normal Blocks (Application Code, User
    > > Parameters and User Data)?

    >
    > > 5) Can that Boot Block area used for other purporses w.r.t
    > > security of the application ?

    >
    > > 6) I understand that for systems with small amounts of memory,
    > > XIP is very good that each instance of that program uses
    > > system RAM, only for their stack, BSS, and data segments
    > > while the shared text segment remains in Flash Memory.

    >
    > > But, Is there any specific Block dedicated for text segment
    > > while performing XIP in either Boot Block Flash Memories
    > > or Uniform Block Flash Memories(Normal Flash Memories)?

    >
    > > 7) Is there any other specific configuration to look for while
    > > selecting the Flash Memory while going in for XIP ?

    >
    > > Any ideas / link / pdf ?

    >
    > > Thx in advans,
    > > Karthik Balaguru

    >
    > Did you already see the "Uniform versus boot block Flash architectures"
    > document from STMicroelectronics.
    > you can find it here:http://www.st.com/stonline/products/...re/an/7105.pdf
    >


    That document is very interesting.
    Thx for that link/document.

    But, it did not address my queries regarding XIP(Execute in Place) &
    cost factors.

    a) Is there any other specific configuration to look for while
    selecting the Flash Memory while going in for XIP ?

    b) Is there any specific Block dedicated for performing XIP
    in either Boot Block Flash Memories or Uniform Block
    Flash Memories(Normal Flash Memories)?

    c) Cost factors

    Karthik Balaguru


  19. Re: Boot Block and Uniform Block Flash Memory and Executin In Place(XIP)

    On Oct 25, 11:51 am, Juergen Beisert wrote:
    > Hi,
    >
    > karthikbalaguru wrote:
    > > My Queries are :-
    > > 1) But, What is the advantage of Top Boot Flash Memory and
    > > What is the advantage of Bottom Boot Flash memory ?

    >
    > Sometimes these special blocks are smaller than the others. This might be an
    > advantage, when you have to store some kind of variable information in it.
    > You waste less space in this case (the bootloader u-boot does so. Sometimes
    > you must waste 256kiB (one sector), but you only need 3kiB for the real
    > data).
    >
    > > 2) Apart from protection to the Boot Block, what are the other
    > > differences between these Boot Block based Flash memories
    > > and Normal Flash Memories (Uniform Block Flash Memory)?

    >
    > AFAIK no other difference.
    >
    > > 3) Which is cost-effective (Boot Block based Flash or Normal
    > > Flash ( Uniform Block Flash Memory) ) ?

    >
    > Prepare your hardware and software to handle both types. Then you can always
    > buy the cheaper one.
    >
    > > 4) Is the lifetime (Number of programmable / erase cycles)
    > > of the Boot Block lesser than or equivalent to that of
    > > the Normal Blocks (Application Code, User
    > > Parameters and User Data)?

    >
    > AFAIK no.
    >
    > > 5) Can that Boot Block area used for other purporses w.r.t
    > > security of the application ?

    >
    > To store data the user can setup at runtime.
    >
    > > 6) I understand that for systems with small amounts of memory,
    > > XIP is very good that each instance of that program uses
    > > system RAM, only for their stack, BSS, and data segments
    > > while the shared text segment remains in Flash Memory.

    >
    > > But, Is there any specific Block dedicated for text segment
    > > while performing XIP in either Boot Block Flash Memories
    > > or Uniform Block Flash Memories(Normal Flash Memories)?

    >
    > The sizes of the sectors are only important, when you are going to erase
    > them (or when you want to run a real filesystem on top of it, like JFFS2).
    > When you read this memory type (=run code from it), they are unimportant.
    >


    Thx for the information provided by you , Norbert van Bolhuis and
    others in all
    these groups. It has given me some good information .

    Karthik Balaguru


  20. Re: Boot Block and Uniform Block Flash Memory and Executin In Place(XIP)

    karthikbalaguru wrote:

    > But, it did not address my queries regarding XIP(Execute in Place) &
    > cost factors.
    >
    > a) Is there any other specific configuration to look for while
    > selecting the Flash Memory while going in for XIP ?


    Yes.

    Speed!

    Any recent microcontroller needs a fast source of code. For XIP, your flash
    should have a asychronous or synchronous page mode.

    regards

    Wolfgang



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