Re: mmc ioctl for hw reset ,partitiing, enhanced area setting, boot partition update.

[NamJae Jeon <linkinjeon@gmail.com>]

Hi. Andrei.

Can I know current status of progress accepting partition mangement patch ?

Thanks.

2011년 4월 4일 오후 9:13, Andrei Warkentin <andreiw@motorola.com>님의 말:
> When the boot partitioning patch is accepted, there will be a short
> patch to add GP partitions in.
>
> Thanks,
> A
>
> 2011/4/4 NamJae Jeon <linkinjeon@gmail.com>:
>> Hi. Andrei
>>
>> I checked this patch [RFC] MMC: MMC boot partitions support). Can it
>> support gerneal purpose partition ? Boot partition be only supported
>> in this patch.
>>
>> Is there another patch for general purpose partitions ?
>>
>> Thanks.
>>
>> 2011년 4월 3일 오후 12:03, NamJae Jeon <linkinjeon@gmail.com>님의 말:
>>> Thanks for your reply.
>>>
>>> 2011. 4. 1. 오후 4:58에 "Andrei Warkentin" <andreiw@motorola.com>님이 작성:
>>>
>>>>
>>>> I highly suggest you read the relevant section in JEDEC eMMC spec, which
>>>> is free.
>>>>
>>>> Writeable attributes in EXT_CSD are manipulated through CMD6.
>>>>
>>>> Thanks,
>>>> A
>>>>
>>>> On Apr 1, 2011 2:51 AM, "NamJae Jeon" <linkinjeon@gmail.com> wrote:
>>>> > Hi. Andrei.
>>>> >
>>>> > For partitioning, you suggest I try to use ioctl of ACMD.
>>>> >
>>>> > I don't understand your means. because EXT_CSD is changed for
>>>> > partitioning not CMD.
>>>> >
>>>> > Would you plz explain more ?
>>>> >
>>>> > Thanks.
>>>> >
>>>> > 2011/3/31 NamJae Jeon <linkinjeon@gmail.com>:
>>>> >> Hi, Andrei.
>>>> >>
>>>> >> Thanks. I will check your information.
>>>> >>
>>>> >>
>>>> >> 2011/3/31 Andrei Warkentin <andreiw@motorola.com>:
>>>> >>> Hi,
>>>> >>>
>>>> >>> On Wed, Mar 30, 2011 at 10:11 AM, NamJae Jeon <linkinjeon@gmail.com>
>>>> >>> wrote:
>>>> >>>> usally, bootloader is stored in boot partition. I suggested ioctl to
>>>> >>>> update bootloader in boot partition not modifing boot partition size.
>>>> >>>>
>>>> >>>
>>>> >>> Maybe I didn't explain myself clearly enough, sorry. The patch I have
>>>> >>> exposes the boot partitions
>>>> >>> as block devices and you can read and write to them without affecting
>>>> >>> the rest of the MMC card.
>>>> >>>
>>>> >>>> and moviNAND(samsung) is needed by boot parittion size setting. and
>>>> >>>> when boot parition size is changed, all user data will be reset, it
>>>> >>>> will be initial status.
>>>> >>>>
>>>> >>>> but iNAND(sandisk) is not needed it. boot partition size is
>>>> >>>> fixed(1MB).
>>>> >>>>
>>>> >>>
>>>> >>> I am unsure what you're talking about. The eMMC 4.41 spec (see 7.2)
>>>> >>> does not allow changing boot partition size.
>>>> >>> It is fixed to a certain size, and that size is specified by the
>>>> >>> BOOT_SIZE_MULTI field in EXT_CSD. For the Toshiba devices
>>>> >>> I have around me (MMC08G, MMC16G and MMC32G), each boot partition (two
>>>> >>> total) is 2MB in size.
>>>> >>>
>>>> >>> I don't think ioctl for accessing device partitions is a good idea,
>>>> >>> because the device partitions are just block devices, so they should
>>>> >>> be exposed as such.
>>>> >>>
>>>> >>
>>>> >>> For device partitioning, to support create General Purpose partitions
>>>> >>> (up to 4), an ioctl is probably needed. You could look at "[PATCH
>>>> >>> resend] mmc: Added ioctl to let userspace apps send ACMDs" by John
>>>> >>> Calixto which was last send March 17th. That's generic enough to
>>>> >>> support partitioning (which is a one time programming procedure
>>>> >>> anyway...so there may be no value of adding a specific ioctl for it,
>>>> >>> considering how dangerous of an operation it is).
>>>> >>>
>>>> >>> A
>>>> >>>
>>>> >>
>>>
>>
>