[lkml]   [2012]   [Apr]   [13]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
    SubjectRe: [PATCH v4 0/7] Add TI EMIF SDRAM controller driver
    On Thu, Apr 12, 2012 at 08:50:55PM +0200, Cousson, Benoit wrote:
    > + Felipe,
    > Hi Paul,
    > On 4/12/2012 7:00 PM, Paul Walmsley wrote:
    > >Hi
    > >
    > >On Thu, 12 Apr 2012, Mohammed, Afzal wrote:
    > >
    > >>On Thu, Apr 12, 2012 at 18:40:45, Greg KH wrote:
    > >>>On Thu, Apr 12, 2012 at 12:17:49PM +0530, Santosh Shilimkar wrote:
    > >>>>I was hoping that we will have some thing like drivers/memory/*
    > >>>>but since it doesn't exist, we used drivers/misc.
    > >>>
    > >>>Why not create it? I have no objection to that, it makes it more
    > >>>obvious as to what this really is.
    > >>
    > >>There is another memory controller used in a few TI SoCs,
    > >>namely GPMC [1], do you prefer having it too there.
    > >>
    > >>As of now it is not a driver, platform code handles GPMC, a patch
    > >>series for converting it into a driver (but still residing in
    > >>platform folder) was sent a few days back [2,3].
    > >
    > >Probably the GPMC driver should go into a slightly different place than
    > >SDRC/EMIF.
    > >
    > >GPMC is actually a general-purpose parallel bus driver. It's used to
    > >interface Ethernet controllers, UARTs, FPGAs, NAND/NOR flash, SRAM, etc.
    > >It cannot be used to control DRAM, at least not without a separate DRAM
    > >controller chip.
    > >
    > >SDRC/EMIF are both DRAM controllers. That's all they do. They can't be
    > >used to control anything else. They implement DRAM refresh, etc.
    > The LPDDR2 spec does consider as well NVM (Non Volatile Memory), so I
    > think we should stick to driver/memory for EMIF.
    > >So perhaps something like drivers/memory/dram/ for the SDRAM controllers,
    > >and maybe drivers/memory/ for the GPMC?
    > In fact Felipe was considering something else for that kind of
    > general purpose bus driver like GMPC, C2C and LLI...
    > ... But I do not remember the name :-)

    the name matters very little :-) But the idea was to avoid writing yet
    another bus driver and just use the platform_bus instead. We would do
    all the channel/port setup before hand and far-end device driver
    wouldn't have to know if it's integrated into the SoC or plugged though

    From the driver's perspective it would look the same.

    [unhandled content-type:application/pgp-signature]
     \ /
      Last update: 2012-04-13 11:11    [W:0.026 / U:1.264 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site