Re: [PATCH v1 12/12] fpga: add max10 get_hw_errinfo callback func

[Russ Weight]

On 9/6/20 10:14 AM, Tom Rix wrote:
> On 9/4/20 4:53 PM, Russ Weight wrote:
>> Extend the MAX10 BMC Security Engine driver to include
>> a function that returns 64 bits of additional HW specific
>> data for errors that require additional information.
>> This callback function enables the hw_errinfo sysfs
>> node in the Intel Security Manager class driver.
>>
>> Signed-off-by: Russ Weight <russell.h.weight@xxxxxxxxx>
>> Reviewed-by: Wu Hao <hao.wu@xxxxxxxxx>
>> ---
>>  drivers/fpga/intel-m10-bmc-secure.c | 27 ++++++++++++++++++++++++++-
>>  1 file changed, 26 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/fpga/intel-m10-bmc-secure.c b/drivers/fpga/intel-m10-bmc-secure.c
>> index 4a66c2d448eb..7fb1c805f654 100644
>> --- a/drivers/fpga/intel-m10-bmc-secure.c
>> +++ b/drivers/fpga/intel-m10-bmc-secure.c
>> @@ -450,6 +450,30 @@ static enum ifpga_sec_err m10bmc_sec_cancel(struct ifpga_sec_mgr *imgr)
>>  	return ret ? IFPGA_SEC_ERR_RW_ERROR : IFPGA_SEC_ERR_NONE;
>>  }
>>  
>> +static u64 m10bmc_sec_hw_errinfo(struct ifpga_sec_mgr *imgr)
>> +{
>> +	struct m10bmc_sec *sec = imgr->priv;
>> +	u32 doorbell = 0, auth_result = 0;
>> +	u64 hw_errinfo = 0;
> hw_errinfo should be initialized to some poison value like -1
>
> to cover the case if either of sys_read's fail.
Yes - that is a good idea. I'll make a change for the next patch version.

- Russ
>
> Tom
>
>> +
>> +	switch (imgr->err_code) {
>> +	case IFPGA_SEC_ERR_HW_ERROR:
>> +	case IFPGA_SEC_ERR_TIMEOUT:
>> +	case IFPGA_SEC_ERR_BUSY:
>> +	case IFPGA_SEC_ERR_WEAROUT:
>> +		if (!m10bmc_sys_read(sec->m10bmc, M10BMC_DOORBELL, &doorbell))
>> +			hw_errinfo = (u64)doorbell << 32;
>> +
>> +		if (!m10bmc_sys_read(sec->m10bmc, M10BMC_AUTH_RESULT,
>> +				     &auth_result))
>> +			hw_errinfo |= (u64)auth_result;
>> +
>> +		return hw_errinfo;
>> +	default:
>> +		return 0;
>> +	}
>> +}
>> +
>>  static const struct ifpga_sec_mgr_ops m10bmc_iops = {
>>  	.user_flash_count = get_qspi_flash_count,
>>  	.bmc_root_entry_hash = get_bmc_root_entry_hash,
>> @@ -467,7 +491,8 @@ static const struct ifpga_sec_mgr_ops m10bmc_iops = {
>>  	.prepare = m10bmc_sec_prepare,
>>  	.write_blk = m10bmc_sec_write_blk,
>>  	.poll_complete = m10bmc_sec_poll_complete,
>> -	.cancel = m10bmc_sec_cancel
>> +	.cancel = m10bmc_sec_cancel,
>> +	.get_hw_errinfo = m10bmc_sec_hw_errinfo
>>  };
>>  
>>  static void ifpga_sec_mgr_uinit(struct m10bmc_sec *sec)