Re: [PATCH v1 1/3] mmc: core: Add raw_boot_mult field to mmc_ext_csd

From: Dmitry Osipenko
Date: Sun Mar 01 2020 - 18:09:16 EST


01.03.2020 13:50, Avri Altman ÐÐÑÐÑ:
> Hi,
>>
>>
>> In order to support parsing of NVIDIA Tegra Partition Table format, we
>> need to know the BOOT_SIZE_MULT value of the Extended CSD register
>> because
>> NVIDIA's bootloader linearizes the boot0/boot1/main partitions into a
>> single virtual space, and thus, all partition addresses are shifted by
>> the size of boot0 + boot1 partitions.
>>
>> Signed-off-by: Dmitry Osipenko <digetx@xxxxxxxxx>
>> ---
>> drivers/mmc/core/mmc.c | 2 ++
>> include/linux/mmc/card.h | 1 +
>> 2 files changed, 3 insertions(+)
>>
>> diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c
>> index f6912ded652d..88e5b4224d3c 100644
>> --- a/drivers/mmc/core/mmc.c
>> +++ b/drivers/mmc/core/mmc.c
>> @@ -417,6 +417,8 @@ static int mmc_decode_ext_csd(struct mmc_card
>> *card, u8 *ext_csd)
>> ext_csd[EXT_CSD_ERASE_TIMEOUT_MULT];
>> card->ext_csd.raw_hc_erase_grp_size =
>> ext_csd[EXT_CSD_HC_ERASE_GRP_SIZE];
>> + card->ext_csd.raw_boot_mult =
>> + ext_csd[EXT_CSD_BOOT_MULT];
> You might want at this point multiply it by 128K,
> And get rid of: part_size = ext_csd[EXT_CSD_BOOT_MULT] << 17;
> Below...

But it's not a *raw* _boot_mult anymore then. I'm not sure that it will
be a worthwhile change.