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

[Alistair Francis]

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.

Alistair

>  }
>
>  static void sd_response_r1_make(SDState *sd, uint8_t *response)
> --
> 2.17.0
>
>