Re: [PATCH 1/2]: OMAP: SDP: Introducing 'board-sdp-flash.c' for flash init

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Tue, Dec 8, 2009 at 12:06 AM, Tony Lindgren <tony@xxxxxxxxxxx> wrote:
> * Vimal Singh <vimal.newwork@xxxxxxxxx> [091206 22:39]:
>> On Sat, Dec 5, 2009 at 3:47 AM, Tony Lindgren <tony@xxxxxxxxxxx> wrote:
>> > Hi,
>> >
>> > * Vimal Singh <vimal.newwork@xxxxxxxxx> [091203 06:09]:
>> >> From 13d52884956a26f93826c443e2b8bd78615f74d6 Mon Sep 17 00:00:00 2001
>> >> From: Vimal Singh <vimalsingh@xxxxxx>
>> >> Date: Thu, 26 Nov 2009 16:10:24 +0530
>> >> Subject: [PATCH] OMAP: SDP: Introducing 'board-sdp-flash.c' for flash init
>> >>
>> >> This patch adds 'board-sdp-flash.c', which could be utilized
>> >> by boards similar to 3430SDP. (For ex: 2430sdp, 36030sdp).
>> >>
>> >> This file does initialization for all three flash devices present
>> >> in SDP boards (NOR, NAND, OneNAND), by finding there 'cs' number
>> >> dynamically using switch setting information (S8: 1-4).
>> >> This also expects partition information from core board files (for
>> >> ex: board-3430sdp.c). Which allows to choose different default
>> >> partitions for different boards.
>> >>
>> >> A new structure is created for this purpose: 'flash_partitions'
>> >> in 'mach/board-sdp.h'. This has two members:
>> >> 1. struct mtd_partition *parts
>> >> 2. int nr_parts
>> >>
>> >> A board file is expected to fill this structure and pass it to
>> >> 'sdp-flsash-init'. Partition information should be passed in
>> >> structure array of 'flash_partitions'. Partition information should
>> >> be passed in below sequence in array:
>> >> NOR
>> >> OneNAND
>> >> NAND
>> >>
>> >> Signed-off-by: Vimal Singh <vimalsingh@xxxxxx>
>> >> ---
>> >>  arch/arm/mach-omap2/board-sdp-flash.c        |  246 ++++++++++++++++++++++++++
>> >>  arch/arm/mach-omap2/include/mach/board-sdp.h |   22 +++
>> >>  arch/arm/plat-omap/include/plat/gpmc.h       |    2 +
>> >>  3 files changed, 270 insertions(+), 0 deletions(-)
>> >>  create mode 100644 arch/arm/mach-omap2/board-sdp-flash.c
>> >>  create mode 100644 arch/arm/mach-omap2/include/mach/board-sdp.h
>> >>
>> >> diff --git a/arch/arm/mach-omap2/board-sdp-flash.c
>> >> b/arch/arm/mach-omap2/board-sdp-flash.c
>> >> new file mode 100644
>> >> index 0000000..fbbcd0e
>> >> --- /dev/null
>> >> +++ b/arch/arm/mach-omap2/board-sdp-flash.c
>> >
>> > <snip>
>> >
>> >> +__init board_nand_init(struct flash_partitions sdp_nand_parts, u8 cs)
>> >> +{
>> >> +     sdp_nand_data.cs                = cs;
>> >> +     sdp_nand_data.parts             = sdp_nand_parts.parts;
>> >> +     sdp_nand_data.nr_parts          = sdp_nand_parts.nr_parts;
>> >> +
>> >> +     sdp_nand_data.gpmc_cs_baseaddr  = (void *)(OMAP34XX_GPMC_VIRT +
>> >> +                                                     GPMC_CS0_BASE +
>> >> +                                                     cs * GPMC_CS_SIZE);
>> >> +     sdp_nand_data.gpmc_baseaddr      = (void *) (OMAP34XX_GPMC_VIRT);
>> >> +
>> >> +     gpmc_nand_init(&sdp_nand_data);
>> >> +}
>> >
>> > This does not look right. You're supposed to use gpmc_cs_request()
>> > for allocating the GPMC area based on the chip select and size.
>>
>> I guess you are getting confuse a bit here:
>> gpmc_baseaddr: is the virtual address for GPMC_REVISION (which is also
>> base address for GPMC).
>> gpmc_cs_baseaddr : This is offset from above to 'GPMC_CONFIG(cs)' for
>> specified cs number.
>>
>> These are needed by nand driver.
>
> Right.. Looks like drivers/mtd/nand/omap2.c needs to be fixed so we
> can get rid of this.
>
> And looks like we already are doing it all over the place anyways :(
>
>> While 'gpmc_cs_request' gives physical address to the device resource.
>> And this is done in 'nand/omap2.c'. This is done in driver itself so
>> that we don't allocate a resource even before driver gets loaded.
>
> Yuk.. The nand driver should be generic.
>
>> >> --- a/arch/arm/plat-omap/include/plat/gpmc.h
>> >> +++ b/arch/arm/plat-omap/include/plat/gpmc.h
>> >> @@ -27,6 +27,8 @@
>> >>
>> >>  #define GPMC_CONFIG          0x50
>> >>  #define GPMC_STATUS          0x54
>> >> +#define GPMC_CS0_BASE                0x60
>> >> +#define GPMC_CS_SIZE         0x30
>> >
>> > The GPMC_CS0_BASE and GPMC_CS_SIZE seem to be values specic to
>> > your board, not for the GPMC hardware.
>>
>> These are offsets and very much specific to GPMC hardware.
>>
>> GPMC_CS0_BASE: is offset from GPMC base to first cs GPMC_CONFIG1 register.
>> GPMC_CS_SIZE : is offset (gap) between next cs config registers, e.i.
>> size for cs config registers.
>
> Let's keep it local until drivers/mtd/nand/omap2.c is fixed.
>
> Care to take a look at using some generic nand driver instead
> if we merge this for now?

To me it seems ok, for now, to get this merged and later we can work
on cleaning 'nand/omap2.c' driver.

-- 
Regards,
Vimal Singh
--
To unsubscribe from this list: send the line "unsubscribe linux-omap" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html

[Index of Archives]     [Linux Arm (vger)]     [ARM Kernel]     [ARM MSM]     [Linux Tegra]     [Linux WPAN Networking]     [Linux Wireless Networking]     [Maemo Users]     [Linux USB Devel]     [Video for Linux]     [Linux Audio Users]     [Yosemite Trails]     [Linux Kernel]     [Linux SCSI]

  Powered by Linux