Re: [Qemu-devel] [PATCH v2 04/14] sdcard: Extract sd_frame48/136_calc_checksum()

[Alistair Francis]

On Wed, May 9, 2018 at 12:15 PM, Philippe Mathieu-Daudé <address@hidden> wrote:
> Hi Alistair,
>
> On 05/09/2018 03:00 PM, Alistair Francis wrote:
>> On Tue, May 8, 2018 at 8:46 PM, Philippe Mathieu-Daudé <address@hidden> 
>> wrote:
>>> It will help when moving this around for qtesting in the next commit.
>>>
>>> Signed-off-by: Philippe Mathieu-Daudé <address@hidden>
>>> ---
>>>  hw/sd/sd.c | 21 ++++++++++++++++++---
>>>  1 file changed, 18 insertions(+), 3 deletions(-)
>>>
>>> diff --git a/hw/sd/sd.c b/hw/sd/sd.c
>>> index 27a70896cd..06607115a7 100644
>>> --- a/hw/sd/sd.c
>>> +++ b/hw/sd/sd.c
>>> @@ -273,6 +273,21 @@ static uint16_t sd_crc16(const void *message, size_t 
>>> width)
>>>      return shift_reg;
>>>  }
>>>
>>> +enum {
>>> +    F48_CONTENT_LENGTH  = 1 /* command */ + 4 /* argument */,
>>> +    F136_CONTENT_LENGTH = 15,
>>> +};
>>> +
>>> +static uint8_t sd_frame48_calc_checksum(const void *content)
>>> +{
>>> +    return sd_crc7(content, F48_CONTENT_LENGTH);
>>> +}
>>> +
>>> +static uint8_t sd_frame136_calc_checksum(const void *content)
>>> +{
>>> +    return (sd_crc7(content, F136_CONTENT_LENGTH) << 1) | 1;
>>> +}
>>> +
>>>  #define OCR_POWER_DELAY_NS      500000 /* 0.5ms */
>>>
>>>  FIELD(OCR, VDD_VOLTAGE_WINDOW,          0, 24)
>>> @@ -352,7 +367,7 @@ static void sd_set_cid(SDState *sd)
>>>      sd->cid[13] = 0x00 |       /* Manufacture date (MDT) */
>>>          ((MDT_YR - 2000) / 10);
>>>      sd->cid[14] = ((MDT_YR % 10) << 4) | MDT_MON;
>>> -    sd->cid[15] = (sd_crc7(sd->cid, 15) << 1) | 1;
>>> +    sd->cid[15] = sd_frame136_calc_checksum(sd->cid);
>>>  }
>>>
>>>  #define HWBLOCK_SHIFT  9                       /* 512 bytes */
>>> @@ -416,7 +431,7 @@ static void sd_set_csd(SDState *sd, uint64_t size)
>>>          sd->csd[13] = 0x40;
>>>          sd->csd[14] = 0x00;
>>>      }
>>> -    sd->csd[15] = (sd_crc7(sd->csd, 15) << 1) | 1;
>>> +    sd->csd[15] = sd_frame136_calc_checksum(sd->csd);
>>>  }
>>>
>>>  static void sd_set_rca(SDState *sd)
>>> @@ -491,7 +506,7 @@ static int sd_req_crc_validate(SDRequest *req)
>>>      buffer[0] = 0x40 | req->cmd;
>>>      stl_be_p(&buffer[1], req->arg);
>>>      return 0;
>>> -    return sd_crc7(buffer, 5) != req->crc;     /* TODO */
>>> +    return sd_frame48_calc_checksum(buffer) != req->crc; /* TODO */
>>
>> This 5 has changed to a 15. Is that on purpose? It should be mentioned
>> in the commit message if it is.
>
> I just extracted this function:
>
>   static uint8_t sd_frame48_calc_checksum(const void *content)
>   {
>       return sd_crc7(content, F48_CONTENT_LENGTH);
>   }
>
> Having:
>
>   enum {
>       F48_CONTENT_LENGTH  = 1 /* command */ + 4 /* argument */,
>
> So F48_CONTENT_LENGTH = 5 as previous.

Ah, I missed the '+ 4 '. I just stopped reading at the comment.

Looks good then:

Reviewed-by: Alistair Francis <address@hidden>

Alistair

>
> This function is later verified with tests from patch 12 of this series.
>
>>
>> Alistair
>>
>>>  }
>>>
>>>  static void sd_response_r1_make(SDState *sd, uint8_t *response)
>>> --
>>> 2.17.0
>>>
>>>