[PATCH v3 1/1] bloblist: Fix bloblist convention checking.

[Raymond Mao]

Hi Levi,

On Tue, 9 Jul 2024 at 16:21, Levi Yun <yeoreum.yun at arm.com> wrote:

> According to recently firmware handsoff spec [1]'s "Register usage at
> handoff
> boundary", Transfer List's signature value was changed from 0x40_b10b
> (3 bytes) to 4a0f_b10b (4 bytes).
>
> As updating of TL's signature, register value of x1/r1 should be:
>
> In aarch32's r1 value should be
>     R1[23:0]: set to the TL signature (4a0f_b10b -> masked range value:
> 0f_b10b)
>     R1[31:24]: version of the register convention ==  1
>
> and
>
> In aarch64's x1 value should be
>     X1[31:0]: set to the TL signature (4a0f_b10b)
>     X1[39:32]: version of the register convention ==  1
>     X1[63:40]: MBZ
> (See the [2] and [3]).
>
> This patch fix problems:
>    1. breaking X1 value with updated specification in aarch64
>         - change of length of signature field.
>
>    2. previous error value set in R1 in arm32.
>         - length of signature should be 24, but it uses 32bit signature.
>
> [1] https://github.com/FirmwareHandoff/firmware_handoff
> [2] https://github.com/FirmwareHandoff/firmware_handoff/issues/32
> [3]
> https://github.com/FirmwareHandoff/firmware_handoff/commit/5aa7aa1d3a1db75213e458d392b751f0707de027
>
> Signed-off-by: Levi Yun <yeoreum.yun at arm.com>
> ---
> v3:
>   - Restore arch/arm/lib/xferlist.c.
>
> v2:
>   - Modify commit message.
>   - Remove wrong swaping check in xferlist_from_boot_arg().
>
>  common/bloblist.c  | 11 ++++++++++-
>  include/bloblist.h |  5 ++++-
>  2 files changed, 14 insertions(+), 2 deletions(-)
>
> diff --git a/common/bloblist.c b/common/bloblist.c
> index 11d6422b69..2008ab4d25 100644
> --- a/common/bloblist.c
> +++ b/common/bloblist.c
> @@ -576,7 +576,16 @@ int bloblist_maybe_init(void)
>
>  int bloblist_check_reg_conv(ulong rfdt, ulong rzero, ulong rsig)
>  {
> -       if (rzero || rsig != (BLOBLIST_MAGIC | BLOBLIST_REGCONV_VER) ||
> +       ulong version = BLOBLIST_REGCONV_VER;
> +       ulong sigval;
> +
> +       sigval = (IS_ENABLED(CONFIG_64BIT)) ?
> +                       ((BLOBLIST_MAGIC & ((1UL <<
> BLOBLIST_REGCONV_SHIFT_64) - 1)) |
> +                        ((version  & BLOBLIST_REGCONV_MASK) <<
> BLOBLIST_REGCONV_SHIFT_64)) :
> +                       ((BLOBLIST_MAGIC & ((1UL <<
> BLOBLIST_REGCONV_SHIFT_32) - 1)) |
> +                        ((version  & BLOBLIST_REGCONV_MASK) <<
> BLOBLIST_REGCONV_SHIFT_32));
> +
> +       if (rzero || rsig != sigval ||
>             rfdt != (ulong)bloblist_find(BLOBLISTT_CONTROL_FDT, 0)) {
>                 gd->bloblist = NULL;  /* Reset the gd bloblist pointer */
>                 return -EIO;
> diff --git a/include/bloblist.h b/include/bloblist.h
> index 7fbdd622bc..f4849f22a0 100644
> --- a/include/bloblist.h
> +++ b/include/bloblist.h
> @@ -83,7 +83,10 @@ enum {
>          * Register convention version should be placed into a higher byte
>          * https://github.com/FirmwareHandoff/firmware_handoff/issues/32
>          */
> -       BLOBLIST_REGCONV_VER    = 1 << 24,
> +       BLOBLIST_REGCONV_SHIFT_64 = 32,
> +       BLOBLIST_REGCONV_SHIFT_32 = 24,
> +       BLOBLIST_REGCONV_MASK = 0xff,
> +       BLOBLIST_REGCONV_VER = 1,
>
> Please remove the "FIXME" on top of your changes.
It was a reminder for the bug of the FW handoff spec.
We don't need it anymore once your patch is merged.

BTW, you might need to resend the patch with a new
subject "[PATCH v2 ....]" instead of following the original
topic when you send a new version.

Regards,
Raymond