On Thu, 2025-03-06 at 10:19 +0100, AngeloGioacchino Del Regno wrote: > External email : Please do not click links or open attachments until > you have verified the sender or the content. > > > Il 06/03/25 09:48, Axe Yang ha scritto: > > Add 'mediatek,disable-single-burst' setting. This property can be > > used to switch bus burst type, from single burst to INCR, which is > > determined by the bus type within the IP. Some versions of the IP > > are using AXI bus, thus this switch is necessary as 'single' is not > > the burst type supported by the bus. > > > > Signed-off-by: Axe Yang <axe.yang@xxxxxxxxxxxx> > > I am mostly sure that this is not something to put in devicetree, but > as > platform data for specific SoC(s), as much as I'm mostly sure that > all of > the instances of the MSDC IP in one SoC will be *all* using either > single > or INCR. No, actually MSDC IPs in one SoC are using different versions. Usually MSDC1 (index from 1) is used as eMMC host, the left hosts are used as SD/SDIO hosts. They have similar designs, but there are still difference. > > So, I think I know the answer but I'll still ask just to be extremely > sure: > > is there any MediaTek SoC that has different IP versions for > different MSDC > instances, and that hence require single burst on one instance and > INCR on > another instance? Yes. Actually every SoC has different IP versions for eMMC and SD/SDIO host as I said. e.g. For MT8168, signel burst bit should be set to 1 for eMMC Host, but 0 for SD/SDIO Host. > > And if there is - is there a pattern? Is it always SDIO requiring > INCR or > always eMMC/SD requiring it? > > No, there is no pattern. Both eMMC and SD/SDIO hosts need to be configured base on IP version. There is no binding relationship between eMMC/SD/SDIO and the burst type. eMMC burst type might be INCR or single, same as SD/SDIO. Regards, Axe > > > --- > > Documentation/devicetree/bindings/mmc/mtk-sd.yaml | 8 ++++++++ > > 1 file changed, 8 insertions(+) > > > > diff --git a/Documentation/devicetree/bindings/mmc/mtk-sd.yaml > > b/Documentation/devicetree/bindings/mmc/mtk-sd.yaml > > index 0debccbd6519..6076aff0a689 100644 > > --- a/Documentation/devicetree/bindings/mmc/mtk-sd.yaml > > +++ b/Documentation/devicetree/bindings/mmc/mtk-sd.yaml > > @@ -100,6 +100,14 @@ properties: > > minimum: 0 > > maximum: 0xffffffff > > > > + mediatek,disable-single-burst: > > + $ref: /schemas/types.yaml#/definitions/flag > > + description: > > + Burst type setting. For some versions of the IP that do not > > use > > + AHB bus, the burst type need to be switched to INCR. > > + If present, use INCR burst type. > > + If not present, use single burst type. > > + > > mediatek,hs200-cmd-int-delay: > > $ref: /schemas/types.yaml#/definitions/uint32 > > description: > > >
