On Fri, Apr 11, 2025 at 12:03:03PM +0200, Konrad Dybcio wrote: > On 4/11/25 11:57 AM, Dmitry Baryshkov wrote: > > On Fri, 11 Apr 2025 at 12:49, Konrad Dybcio > > <konrad.dyb...@oss.qualcomm.com> wrote: > >> > >> On 4/9/25 5:49 PM, Konrad Dybcio wrote: > >>> On 4/9/25 5:44 PM, Dmitry Baryshkov wrote: > >>>> On 09/04/2025 17:47, Konrad Dybcio wrote: > >>>>> SMEM allows the OS to retrieve information about the DDR memory. > >>>>> Among that information, is a semi-magic value called 'HBB', or Highest > >>>>> Bank address Bit, which multimedia drivers (for hardware like Adreno > >>>>> and MDSS) must retrieve in order to program the IP blocks correctly. > >>>>> > >>>>> This series introduces an API to retrieve that value, uses it in the > >>>>> aforementioned programming sequences and exposes available DDR > >>>>> frequencies in debugfs (to e.g. pass to aoss_qmp debugfs). More > >>>>> information can be exposed in the future, as needed. > >>>> > >>>> I know that for some platforms HBB differs between GPU and DPU (as it's > >>>> being programmed currently). Is there a way to check, which values are > >>>> we going to program: > >>>> > >>>> - SM6115, SM6350, SM6375 (13 vs 14) > >> > >> SM6350 has INFO_V3 > >> SM6375 has INFO_V3_WITH_14_FREQS > > > > I'm not completely sure what you mean here. I pointed out that these > > platforms disagreed upon the HBB value between the DPU/msm_mdss.c and > > a6xx_gpu.c. > > In some cases (a610/SM6115 and a619/SM6350) that was intentional to > > fix screen corruption issues. I don't remember if it was the case for > > QCM2290 or not. > > As I said below, I couldn't get a good answer yet, as the magic value > is not provided explicitly and I'll hopefully be able to derive it from > the available data
I see... Is this data even supposed to be poked into? The foo_WITH_bar types doesn't sound like a very stable API. > > Konrad > > > > >> > >>>> - SC8180X (15 vs 16) > >> > >> So I overlooked the fact that DDR info v3 (e.g. on 8180) doesn't provide > >> the HBB value.. Need to add some more sanity checks there. > >> > >> Maybe I can think up some fallback logic based on the DDR type reported. > >> > >>>> - QCM2290 (14 vs 15) > >> > >> I don't have one on hand, could you please give it a go on your RB1? > >> I would assume both it and SM6115 also provide v3 though.. > >> > >> Konrad > > > > > > -- With best wishes Dmitry
