On 23 October 2022 05:11:41 IST, Hal Feng <hal.feng@xxxxxxxxxxxxxxxxxxxxxx> wrote: >On Wed, 12 Oct 2022 16:05:23 -0700, Stephen Boyd wrote: >> Quoting Emil Renner Berthing (2022-10-05 06:14:44) >> > > > @@ -295,11 +296,13 @@ static int __init clk_starfive_jh7100_probe(struct platform_device *pdev) >> > > > if (!priv) >> > > > return -ENOMEM; >> > > > >> > > > - spin_lock_init(&priv->rmw_lock); >> > > > priv->dev = &pdev->dev; >> > > > - priv->base = devm_platform_ioremap_resource(pdev, 0); >> > > > - if (IS_ERR(priv->base)) >> > > > - return PTR_ERR(priv->base); >> > > > + priv->regmap = device_node_to_regmap(priv->dev->of_node); >> > > >> > > This is sad. Why do we need to make a syscon? Can we instead use the >> > > auxiliary bus to make a reset device that either gets a regmap made here >> > > in this driver or uses a void __iomem * mapped with ioremap >> > > (priv->base)? >> > >> > In my original code the clock driver just registers the resets too >> > similar to other combined clock and reset drivers. I wonder what you >> > think about that approach: >> > https://github.com/esmil/linux/commit/36f15e1b827b02d7f493dc5fce31060b21976e68 >> > and >> > https://github.com/esmil/linux/commit/4ccafadb72968480aa3dd28c227fcccae411c13b#diff-ffec81f902f810cb210012c25e8d88217ea5b4021419a4206d1fd4dd19edfce8R471 >> >> I think we should use auxiliary bus and split the driver logically into >> a reset driver in drivers/reset and a clk driver in drivers/clk. That >> way the appropriate maintainers can review the code. There is only one >> platform device with a single reg property and node in DT, but there are >> two drivers. > >Yes, I agree that the reset driver and the clock driver should be split. >However, I think using auxiliary bus is a little bit complicated in this >case, because the reset is not a part of functionality of the clock in >JH7110. They just share a common register base address. I think it is >better to use ioremap for the same address, and the dt will be like > >syscrg_clk: clock-controller@13020000 { > compatible = "starfive,jh7110-clkgen-sys"; > reg = <0x0 0x13020000 0x0 0x10000>; > ... >}; >syscrg_rst: reset-controller@13020000 { > compatible = "starfive,jh7110-reset-sys"; > reg = <0x0 0x13020000 0x0 0x10000>; > ... >}; > >What do you think of this approach? I would appreciate your suggestions. No, the dtb checks will all start warning for this. Aux bus is not that difficult, you can likely copy much of what I did recently in clk-mpfs.c > >Best regards, >Hal
