[PATCH v2 1/1] fastboot: fb_getvar: Add getvar_logical_blocksize for NXP mfgtool

[Angus Ainslie]

Hi Sean,

On 2021-12-28 08:59, Sean Anderson wrote:
> Hi Angus,
> 
>> NXP's mfgtool queies the mmc blocksize and splits a sparse image into
>> blocksize size pieces for the upload.
> 
> It's still not clear to me why this is necessary. fastboot (for 
> example)
> transfers in blocks of max-download-size. Using the actual block size
> seems like it would result in unnecessary overhead.
> 

The version of uuu that we are using requires the block-size for the 
sparse upload

https://source.puri.sm/Librem5/mfgtools/-/blob/pureos/amber/libuuu/fastboot.cpp#L501

It looks like the upstream version will default to 4096 if the 
block-size is not provided

https://github.com/NXPmicro/mfgtools/blob/5397913ad97db422c1d70f314dedff4cb7d976b9/libuuu/fastboot.cpp#L642

Instead of making assumptions about the block size wouldn't it be better 
to provide one if requested ?

We could also remove that being a required parameter from the uuu that 
we are using but that still leaves versions out there that won't work 
with a mainline u-boot.

Thanks
Angus

> --Sean
> 
>> Signed-off-by: Angus Ainslie <angus at akkea.ca>
>> ---
>>   drivers/fastboot/fb_getvar.c | 21 +++++++++++++++++++++
>>   1 file changed, 21 insertions(+)
>> 
>> diff --git a/drivers/fastboot/fb_getvar.c 
>> b/drivers/fastboot/fb_getvar.c
>> index d43f2cfee6..3cb72b8a54 100644
>> --- a/drivers/fastboot/fb_getvar.c
>> +++ b/drivers/fastboot/fb_getvar.c
>> @@ -26,6 +26,7 @@ static void getvar_has_slot(char *var_parameter, 
>> char *response);
>>   #endif
>>   #if CONFIG_IS_ENABLED(FASTBOOT_FLASH_MMC)
>>   static void getvar_partition_type(char *part_name, char *response);
>> +static void getvar_logical_blocksize(char *var_parameter, char 
>> *response);
>>   #endif
>>   #if CONFIG_IS_ENABLED(FASTBOOT_FLASH)
>>   static void getvar_partition_size(char *part_name, char *response);
>> @@ -72,6 +73,9 @@ static const struct {
>>   	}, {
>>   		.variable = "partition-type",
>>   		.dispatch = getvar_partition_type
>> +	}, {
>> +		.variable = "logical-block-size",
>> +		.dispatch = getvar_logical_blocksize
>>   #endif
>>   #if CONFIG_IS_ENABLED(FASTBOOT_FLASH)
>>   	}, {
>> @@ -232,6 +236,23 @@ static void getvar_partition_type(char 
>> *part_name, char *response)
>>   			fastboot_okay(fs_get_type_name(), response);
>>   	}
>>   }
>> +
>> +static void getvar_logical_blocksize(char *var_parameter, char 
>> *response)
>> +{
>> +	u32 blksz;
>> +	struct blk_desc *dev_desc;
>> +
>> +	dev_desc = blk_get_dev("mmc", CONFIG_FASTBOOT_FLASH_MMC_DEV);
>> +
>> +	if (!dev_desc) {
>> +		pr_err("** Block device mmc %d not supported\n",
>> +		       CONFIG_FASTBOOT_FLASH_MMC_DEV);
>> +		fastboot_fail("Get logical_blocksize failed", response);
>> +		return;
>> +	}
>> +
>> +	fastboot_response("OKAY", response, "0x%08x", dev_desc->blksz);
>> +}
>>   #endif
>> 
>>   #if CONFIG_IS_ENABLED(FASTBOOT_FLASH)
>>