Messages in this thread | | | Date | Thu, 29 Dec 2005 15:17:19 -0400 | From | Anderson Lizardo <> | Subject | Re: [patch 0/5] Add MMC password protection (lock/unlock) support |
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On 12/15/05, Russell King <rmk+lkml@arm.linux.org.uk> wrote: > Reading through the specs I have here, block sizes seem to be all over > the place. The MMC card specs seem to imply that any block size can > be set, from 0 bytes to 2^32-1 bytes. > > The PXA MMC interface specification allows the block size to be anything > from 1 to 1023 bytes, excluding CRC. It is unclear whether a value of 0 > means 1024. > > The MMCI specification allows the block size to be specified as a power > of two, from 1 to 2048 bytes, excluding CRC.
By "allows" do you mean we can set the block size to arbitrary values on MMCI too?
The MMC specification v4.1 is clear in one thing: the SET_BLOCKLEN command should be issued prior to the actual LOCK_UNLOCK command with *exactly* the password length + 2 bytes (which contains the operation mode bits and the password length in bytes). The MMC password unlocking (and other password operations, FWIW) doesn't work on the OMAP host if the SET_BLOCKLEN command argument and the block size of the data transfer itself do not match.
-- Anderson Lizardo Embedded Linux Lab - 10LE Nokia Institute of Technology - INdT Manaus - Brazil - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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