[PATCH 3/4] cmd: mmc: display write protect state of boot partition

[Heinrich Schuchardt]

On 4/1/20 5:04 AM, Jaehoon Chung wrote:
> Hi,
>
> On 3/30/20 2:24 PM, Heinrich Schuchardt wrote:
>> Boot partitions of eMMC devices can be power on or permanently write
>> protected. Let the 'mmc info' command display the protection state.
>>
>> Signed-off-by: Heinrich Schuchardt <xypron.glpk at gmx.de>
>> ---
>>  cmd/mmc.c | 24 ++++++++++++++++++++++++
>>  1 file changed, 24 insertions(+)
>>
>> diff --git a/cmd/mmc.c b/cmd/mmc.c
>> index 6f3cb85cc0..d62c85e439 100644
>> --- a/cmd/mmc.c
>> +++ b/cmd/mmc.c
>> @@ -54,6 +54,8 @@ static void print_mmcinfo(struct mmc *mmc)
>>  	if (!IS_SD(mmc) && mmc->version >= MMC_VERSION_4_41) {
>>  		bool has_enh = (mmc->part_support & ENHNCD_SUPPORT) != 0;
>>  		bool usr_enh = has_enh && (mmc->part_attr & EXT_CSD_ENH_USR);
>> +		u8 wp, ext_csd[MMC_MAX_BLOCK_LEN];
>> +		int ret;
>>
>>  #if CONFIG_IS_ENABLED(MMC_HW_PARTITIONING)
>>  		puts("HC WP Group Size: ");
>> @@ -90,6 +92,28 @@ static void print_mmcinfo(struct mmc *mmc)
>>  					putc('\n');
>>  			}
>>  		}
>> +		ret = mmc_send_ext_csd(mmc, ext_csd);
>> +		if (ret)
>> +			return;
>
> Is it really needed to call mmc_send_ext_csd() at here.
> ext_csd register value was already read somewhere.

struct mmc does not contain the extended CSD. Performancewise it does
not make sense to carry a copy which would have to be updated after each
command that could potentially update it like SWITCH.

The call to mmc_send_ext_csd() does not lead to any visible performance
issue here.

Best regards

Heinrich

>
> Best Regards,
> Jaehoon Chung
>
>> +		wp = ext_csd[EXT_CSD_BOOT_WP_STATUS];
>> +		for (i = 0; i < 2; ++i) {
>> +			printf("Boot area %d is ", i);
>> +			switch (wp & 3) {
>> +			case 0:
>> +				printf("not write protected\n");
>> +				break;
>> +			case 1:
>> +				printf("power on protected\n");
>> +				break;
>> +			case 2:
>> +				printf("permanently protected\n");
>> +				break;
>> +			default:
>> +				printf("in reserved protection state\n");
>> +				break;
>> +			}
>> +			wp >>= 2;
>> +		}
>>  	}
>>  }
>>  static struct mmc *init_mmc_device(int dev, bool force_init)
>> --
>> 2.25.1
>>
>>
>>
>