Re: [PATCH 5/7] media: verisilicon: Add Rockchip VPU720 JPEG decoder

[Sascha Hauer]

On 2026-08-20 12:02, Nicolas Dufresne wrote:
> Hi Sascha,
> 
> Le jeudi 20 août 2026 à 10:03 +0000, Sascha Hauer a écrit :
> > On 2026-08-19 11:48, Nicolas Dufresne wrote:
> > > Hi Sascha,
> > > 
> > > Le mercredi 19 août 2026 à 12:37 +0200, Sascha Hauer a écrit :
> > > > +/* ------------------------------------------------------------------ */
> > > > +/* Register byte offsets from dec_base                                 */
> > > > +/* ------------------------------------------------------------------ */
> > > > +
> > > > +/* REG0: IP version / product ID */
> > > > +#define VDPU720_REG_VERSION		0x000
> > > > +#define VDPU720_PROD_NUM		GENMASK(31, 16)
> > > > +#define VDPU720_BIT_DEPTH		BIT(8)
> > > 
> > > Can you share a dump and share these register reset values. Looking at the
> > > layout, clearly its highly modified, but probably derived from VSI multi-codec,
> > > but I'm thinking perhaps we'll learn more from that. Its always nice to justify
> > > when adding more chips that are not strictly VSI designs (or maybe it is) to the
> > > hantro dirver.
> > 
> > Here's a full register dump right after reset:
> > 
> > 00000000: db1f0005 00000004 00120000 00000000
> 
> I've look around as much as I could, and could not find any indication that this
> is an IP from VSI or derived from a VSI core. It is entirely different from
> vdpu1 in mpp (proper G1, rk3288 and similar) and vdpu2 (modified G1 / VDPU121).
> In short, this is not a multi-codec core.
> 
> So that ball is on your end to show that this driver belongs to hantro rather
> then its own driver. In absence of evidence, this driver should be part of
> rockchip vendor folder, not vsi. Don't read me wrong, I trust that you have
> tested what the LLM have chosen, but anything can be implement in Hantro really,
> it does not mean it should be there.

I won't argue that the driver belongs to hantro because apparently it doesn't.
I don't know where the decision to integrate it into hantro is coming
from, maybe just because the Rockchip JPEG encoder is also there.
Anyway, I'll start with a fresh series with a standalone driver.

Patches 1-3 could be useful on their own though, so you might want to
take them. They are untested on real Hantro hardware, but I could give
them a go on the JPEG encoder.

Sascha


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