RE: Re: [PATCH v31 2/4] scsi: ufs: L2P map management for HPB read

[Daejun Park <daejun7.park@samsung.com>]

Hi Bean,

>On Mon, 2021-03-22 at 15:54 +0900, Daejun Park wrote:
>> +       switch (rsp_field->hpb_op) {
>> 
>> +       case HPB_RSP_REQ_REGION_UPDATE:
>> 
>> +               if (data_seg_len != DEV_DATA_SEG_LEN)
>> 
>> +                       dev_warn(&hpb->sdev_ufs_lu->sdev_dev,
>> 
>> +                                "%s: data seg length is not
>> same.\n",
>> 
>> +                                __func__);
>> 
>> +               ufshpb_rsp_req_region_update(hpb, rsp_field);
>> 
>> +               break;
>> 
>> +       case HPB_RSP_DEV_RESET:
>> 
>> +               dev_warn(&hpb->sdev_ufs_lu->sdev_dev,
>> 
>> +                        "UFS device lost HPB information during
>> PM.\n");
>> 
>> +               break;
> 
>Hi Deajun,
>This series looks good to me. Just here I have one question. You didn't

Thanks.

>handle HPB_RSP_DEV_RESET, just a warning.  Based on your SS UFS, how to
>handle HPB_RSP_DEV_RESET from the host side? Do you think we shoud
>reset host side HPB entry as well or what else?

In the JEDEC HPB spec, it as follows:

When the device is powered off by the host, the device may restore L2P map
data upon power up or build from the host’s HPB READ command.

So I think there is nothing to do, because UFS can build from host's
command. Moreover, in the case of the HPB read with invalid information by
dev reset, it just processed as normal read.

Thanks,
Daejun
> 
> 
>Bean
> 
> 
> 
>