> -----Original Message----- > From: Krzysztof Kozlowski [mailto:krzysztof.kozlowski@xxxxxxxxxx] > Sent: 18 August 2023 14:57 > To: Sriranjani P <sriranjani.p@xxxxxxxxxxx>; davem@xxxxxxxxxxxxx; > edumazet@xxxxxxxxxx; kuba@xxxxxxxxxx; pabeni@xxxxxxxxxx; > robh+dt@xxxxxxxxxx; krzysztof.kozlowski+dt@xxxxxxxxxx; > conor+dt@xxxxxxxxxx; richardcochran@xxxxxxxxx; > alexandre.torgue@xxxxxxxxxxx; joabreu@xxxxxxxxxxxx; > mcoquelin.stm32@xxxxxxxxx; alim.akhtar@xxxxxxxxxxx; linux- > fsd@xxxxxxxxx; pankaj.dubey@xxxxxxxxxxx; swathi.ks@xxxxxxxxxxx; > ravi.patel@xxxxxxxxxxx > Cc: netdev@xxxxxxxxxxxxxxx; devicetree@xxxxxxxxxxxxxxx; linux- > kernel@xxxxxxxxxxxxxxx; linux-samsung-soc@xxxxxxxxxxxxxxx; linux-arm- > kernel@xxxxxxxxxxxxxxxxxxx; 'Chandrasekar R' <rcsekar@xxxxxxxxxxx>; > 'Suresh Siddha' <ssiddha@xxxxxxxxx> > Subject: Re: [PATCH v3 2/4] net: stmmac: dwc-qos: Add FSD EQoS support > > On 16/08/2023 08:38, Sriranjani P wrote: > > > > > >> -----Original Message----- > >> From: Krzysztof Kozlowski [mailto:krzysztof.kozlowski@xxxxxxxxxx] > >> Sent: 15 August 2023 01:21 > >> To: Sriranjani P <sriranjani.p@xxxxxxxxxxx>; davem@xxxxxxxxxxxxx; > >> edumazet@xxxxxxxxxx; kuba@xxxxxxxxxx; pabeni@xxxxxxxxxx; > >> robh+dt@xxxxxxxxxx; krzysztof.kozlowski+dt@xxxxxxxxxx; > >> conor+dt@xxxxxxxxxx; richardcochran@xxxxxxxxx; > >> alexandre.torgue@xxxxxxxxxxx; joabreu@xxxxxxxxxxxx; > >> mcoquelin.stm32@xxxxxxxxx; alim.akhtar@xxxxxxxxxxx; linux- > >> fsd@xxxxxxxxx; pankaj.dubey@xxxxxxxxxxx; swathi.ks@xxxxxxxxxxx; > >> ravi.patel@xxxxxxxxxxx > >> Cc: netdev@xxxxxxxxxxxxxxx; devicetree@xxxxxxxxxxxxxxx; linux- > >> kernel@xxxxxxxxxxxxxxx; linux-samsung-soc@xxxxxxxxxxxxxxx; linux-arm- > >> kernel@xxxxxxxxxxxxxxxxxxx; Chandrasekar R <rcsekar@xxxxxxxxxxx>; > >> Suresh Siddha <ssiddha@xxxxxxxxx> > >> Subject: Re: [PATCH v3 2/4] net: stmmac: dwc-qos: Add FSD EQoS > >> support > >> > >> On 14/08/2023 13:25, Sriranjani P wrote: > >>> The FSD SoC contains two instance of the Synopsys DWC ethernet QOS > >>> IP > >> core. > >>> The binding that it uses is slightly different from existing ones > >>> because of the integration (clocks, resets). > >>> > >>> For FSD SoC, a mux switch is needed between internal and external > clocks. > >>> By default after reset internal clock is used but for receiving > >>> packets properly, external clock is needed. Mux switch to external > >>> clock happens only when the external clock is present. > >>> > >>> Signed-off-by: Chandrasekar R <rcsekar@xxxxxxxxxxx> > >>> Signed-off-by: Suresh Siddha <ssiddha@xxxxxxxxx> > >>> Signed-off-by: Swathi K S <swathi.ks@xxxxxxxxxxx> > >>> Signed-off-by: Sriranjani P <sriranjani.p@xxxxxxxxxxx> > >>> --- > >> > >> > >>> +static int dwc_eqos_setup_rxclock(struct platform_device *pdev, int > >>> +ins_num) { > >>> + struct device_node *np = pdev->dev.of_node; > >>> + struct regmap *syscon; > >>> + unsigned int reg; > >>> + > >>> + if (np && of_property_read_bool(np, "fsd-rx-clock-skew")) { > >>> + syscon = syscon_regmap_lookup_by_phandle_args(np, > >>> + "fsd-rx-clock- > >> skew", > >>> + 1, ®); > >>> + if (IS_ERR(syscon)) { > >>> + dev_err(&pdev->dev, > >>> + "couldn't get the rx-clock-skew syscon!\n"); > >>> + return PTR_ERR(syscon); > >>> + } > >>> + > >>> + regmap_write(syscon, reg, rx_clock_skew_val[ins_num]); > >>> + } > >>> + > >>> + return 0; > >>> +} > >>> + > >>> +static int fsd_eqos_clk_init(struct fsd_eqos_plat_data *plat, > >>> + struct plat_stmmacenet_data *data) { > >>> + int ret = 0, i; > >>> + > >>> + const struct fsd_eqos_variant *fsd_eqos_v_data = > >>> + plat->fsd_eqos_inst_var; > >>> + > >>> + plat->clks = devm_kcalloc(plat->dev, fsd_eqos_v_data->num_clks, > >>> + sizeof(*plat->clks), GFP_KERNEL); > >>> + if (!plat->clks) > >>> + return -ENOMEM; > >>> + > >>> + for (i = 0; i < fsd_eqos_v_data->num_clks; i++) > >>> + plat->clks[i].id = fsd_eqos_v_data->clk_list[i]; > >>> + > >>> + ret = devm_clk_bulk_get(plat->dev, fsd_eqos_v_data->num_clks, > >>> + plat->clks); > >> > >> Instead of duplicating entire clock management with existing code, > >> you should extend/rework existing one. > >> > >> This code is unfortunately great example how not to stuff vendor code > >> into upstream project. :( > > > > I will check again if I can extend existing one to support FSD platform > specific requirement. > > > >> > >>> + > >>> + return ret; > >>> +} > >>> + > >>> +static int fsd_clks_endisable(void *priv, bool enabled) { > >>> + int ret, num_clks; > >>> + struct fsd_eqos_plat_data *plat = priv; > >>> + > >>> + num_clks = plat->fsd_eqos_inst_var->num_clks; > >>> + > >>> + if (enabled) { > >>> + ret = clk_bulk_prepare_enable(num_clks, plat->clks); > >>> + if (ret) { > >>> + dev_err(plat->dev, "Clock enable failed, err = %d\n", > >> ret); > >>> + return ret; > >>> + } > >>> + } else { > >>> + clk_bulk_disable_unprepare(num_clks, plat->clks); > >>> + } > >>> + > >>> + return 0; > >>> +} > >>> + > >>> +static int fsd_eqos_probe(struct platform_device *pdev, > >>> + struct plat_stmmacenet_data *data, > >>> + struct stmmac_resources *res) > >>> +{ > >>> + struct fsd_eqos_plat_data *priv_plat; > >>> + struct device_node *np = pdev->dev.of_node; > >>> + int ret = 0; > >>> + > >>> + priv_plat = devm_kzalloc(&pdev->dev, sizeof(*priv_plat), > >> GFP_KERNEL); > >>> + if (!priv_plat) { > >>> + ret = -ENOMEM; > >> > >> return -ENOMEM > > > > Will fix this in v4. > > > >> > >>> + goto error; > >>> + } > >>> + > >>> + priv_plat->dev = &pdev->dev; > >>> + data->bus_id = of_alias_get_id(np, "eth"); > >> > >> No, you cannot do like this. Aliases are board specific and are based > >> on labeling on the board. > > > > So if I understood this correctly, I need to move alias in the board > > specific DTS file > > This part: yes > > > and I can use this, because we have to handle rx-clock-skew differently for > the two instances in the FSD platform. > > Not really. Do you expect it to work correctly if given EQoS instance receives > different alias, e.g. 5? > > > Another approach we took in v1, by specifying the value to be programmed > in rx-clock-skew property itself, but it seems it is not a preferred approach. > > I can see that in drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c > +436 common code is already using this API and getting alias id, so I can > probably use the same rather getting same again here, but I have to specify > alias in DTS file. > > Getting alias ID is okay in general. It is used to provide user-visible ID of the > devices (see mmc). Using such alias to configure hardware is abuse of the > alias, because of the reasons I said - how is it supposed to work if alias is 5 > (this is perfectly valid alias)? > > I suspect that all this is to substitute missing abstractions, like clocks, phys or > resets... Will avoid using the API to get alias id to configure the HW. Will share the new implementation in v4. > > Best regards, > Krzysztof Regards, Swathi
