On Tue, Nov 15, 2022 at 09:12:54AM +0100, Krzysztof Kozlowski wrote: > On 14/11/2022 18:08, Johan Hovold wrote: > >> > >> Which is also fine. I don't understand still why it is a problem - even > >> if you have multiple files, one for each SoC/phy. If USB4 brings here 10 > >> more clocks and other SoCs/phys might bring many more options, then what > >> else can you do? Grow the binding file with big text-based mapping of > >> IDs? It's not a viable solution. Header or headers is the only > >> maintainable way for such cases. > > > > So then we must add per-SoC (and PHY type) headers even if we can > > possibly reuse defines from one platform for another as long as they > > appear to be similar enough? > > No, you don't have to. I just got impression that future devices will > bring so many changes that anyway you will end up with per-SoC defines. > > > For example, using a "SC7180_USB3_DP" infix > > for the current platforms and add a new series of indexes for SC8280XP: > > > > QMP_SC7180_USB3_DP_USB3_PIPE 0 > > QMP_SC7180_USB3_DP_DP_LINK 1 > > QMP_SC7180_USB3_DP_DP_VCO_DIV 2 > > > > QMP_SC8280XP_USB4_USB3_DP_USB3_PIPE 0 > > QMP_SC8280XP_USB4_USB3_DP_DP_LINK 1 > > QMP_SC8280XP_USB4_USB3_DP_DP_VCO_DIV 2 > > QMP_SC8280XP_USB4_USB3_DP_USB4_PCIE_PIPE 3 > > ... > > QMP_SC8280XP_USB4_USB3_DP_USB4_RX1 9 > > The names are just a names, you can even use QMP_SC7180_* on SC8280XP. > You can skip the SoC part and have something shared. We already have > such patterns - although maybe more often for outside components (like > PMICs). The differences are: > 1. For per-SoC name it's quite obvious which clock is supported on fiven > SoC, > 2. With shared names, you should document somewhere mapping between > supported clocks and SoCs. Also what to do if new device comes with 10 > new clocks entirely different - re-use/map existing defines or add > completely new set of 10 of them? Ok, thanks. I'll go with a common prefix per PHY type for now, and we can worry about hypothetical hardware revisions later. I'll use a "QMP_USB43DP_" prefix for the new SC8280XP binding, which can be reused also for the older SoCs with USB3-DP PHYs if/when we convert them as their indexes will be a subset of the SC8280XP ones: /* QMP USB4-USB3-DP clocks */ #define QMP_USB43DP_USB3_PIPE_CLK 0 #define QMP_USB43DP_DP_LINK_CLK 1 #define QMP_USB43DP_DP_VCO_DIV_CLK 2 Since I'm adding a new header anyway, I decided to go with dedicated indexes also for the PHY selection (instead of using the PHY_TYPE defines): /* QMP USB4-USB3-DP PHYs */ #define QMP_USB43DP_USB3_PHY 0 #define QMP_USB43DP_DP_PHY 1 I'll add these to a common dt-bindings/phy/phy-qcom-qmp.h header so that it can be used also for the UFS clocks (with a "QMP_UFS_" prefix). Johan
