Re: [PATCH] misc: aspeed_scu: Update AST2600 silicon id register

[Cédric Le Goater]

On 9/16/20 10:20 AM, Joel Stanley wrote:
> Aspeed have released an updated datasheet (v7) containing the silicon id
> for the AST2600 A2. It looks like this:
> 
>               SCU004      SCU014
>   AST2600-A0  0x05000303  0x05000303
>   AST2600-A1  0x05010303  0x05010303
>   AST2600-A2  0x05010303  0x05020303
>   AST2620-A1  0x05010203  0x05010203
>   AST2620-A2  0x05010203  0x05020203
> 
> The SCU004 (silicon id 1) value matches SCU014 for A0, but for
> subsequent revisions it is hard coded to the A1 value.
> 
> Qemu effectively dropped support for the A0 in 7582591ae745 ("aspeed:
> Support AST2600A1 silicon revision") as the A0 reset table was removed,
> so it makes sense to only support the behaviour of A1 and onwards.
> 
> Signed-off-by: Joel Stanley <joel@jms.id.au>

Reviewed-by: Cédric Le Goater <clg@kaod.org>

> ---
>  hw/misc/aspeed_scu.c | 7 ++++++-
>  1 file changed, 6 insertions(+), 1 deletion(-)
> 
> diff --git a/hw/misc/aspeed_scu.c b/hw/misc/aspeed_scu.c
> index dc6dd87c22f4..40a38ebd8549 100644
> --- a/hw/misc/aspeed_scu.c
> +++ b/hw/misc/aspeed_scu.c
> @@ -670,7 +670,12 @@ static void aspeed_ast2600_scu_reset(DeviceState *dev)
>  
>      memcpy(s->regs, asc->resets, asc->nr_regs * 4);
>  
> -    s->regs[AST2600_SILICON_REV] = s->silicon_rev;
> +    /*
> +     * A0 reports A0 in _REV, but subsequent revisions report A1 regardless
> +     * of actual revision. QEMU and Linux only support A1 onwards so this is
> +     * sufficient.
> +     */
> +    s->regs[AST2600_SILICON_REV] = AST2600_A1_SILICON_REV;
>      s->regs[AST2600_SILICON_REV2] = s->silicon_rev;
>      s->regs[AST2600_HW_STRAP1] = s->hw_strap1;
>      s->regs[AST2600_HW_STRAP2] = s->hw_strap2;
>