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SubjectRe: MMC block addressing mode.
On 04/20/2017 09:18 AM, Ulf Hansson wrote:
>> The Cavium hardware requires knowledge of the card addressing mode.
>> We need to either restore mmc_card_blockaddr(), or create another
>> way to generate the same information. You previously suggested use
>> of the 'blksz' value, however, it has the same value regardless of
>> the card capacity. What would you suggest? Cheers.
> Right. Can you explain what the Cavium hardware need it for?

In Cavium's MMC controller, the DMA engine requires software to
specify the addressing mode of the card. For DMA write operations,
the CARD_ADDR field in the MIO_EMM_DMA register is programmed with
a byte address if the media card <= 2GB. If the card is > 2GB, the
address is interpreted as a 512 byte sector address. The SECTOR bit
tells the controller how to interpret the address in CARD_ADDR. If
set to 1, use 512 byte sector addressing, otherwise it is set to 0
and byte addressing is used.


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