On Tue, 26 Dec 2023 19:00:58 -0800 (PST) "K. James" <kirby.nankiv...@gmail.com> wrote:
Hi, please try to avoid HTML email on lists, that makes it hard to reply inline and messes up the text view - and there is little need to provide links to every identifier anyway. > Hi All, > > Been working on getting T113-s3 on mainline as I prepare to update a > project from a v3s. One of the benefits has been the ability to move from a > 18bit RGB LCD to a MIPI-DSI display, with the interface available on the > T113-s3 , which has given some better display choices. > > The DSI driver was on mainline from 6.2, however building from sources on > init I am getting the following error: > > *"sun6i-mipi-dsi 5450000.dsi: Couldn't get the DSI mod clock"* > > Its tripping at the following init in sun6i_mipi_dsi.c > <https://elixir.bootlin.com/linux/v6.6.2/source/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c#L1155> > > > if (variant-> has_mod_clk) { > dsi->mod_clk = devm_clk_get(dev, "mod"); > if (IS_ERR (dsi->mod_clk)) { > dev_err(dev, "Couldn't get the DSI mod clock\n"); > ret = PTR_ERR(dsi->mod_clk); > goto err_attach_clk; >} But since this comes from the DSI driver, this refers to the DT node of the DSI device, not the DE2 clock, doesn't it? > The display modclock is registered from the following DTS node in > sunxi-d1s-t113.dtsi > <https://elixir.bootlin.com/linux/v6.6.2/source/arch/riscv/boot/dts/allwinner/sunxi-d1s-t113.dtsi#L641> > > > display_clocks: clock-controller@5000000 { > compatible = "allwinner,sun20i-d1-de2-clk", > "allwinner,sun50i-h5-de2-clk"; > reg = <0x5000000 0x10000>; > clocks = <&ccu CLK_BUS_DE>, <&ccu CLK_DE>; > clock-names = "bus", *"mod"*; > resets = <&ccu RST_BUS_DE>; > #clock-cells = <1>; > #reset-cells = <1>; > }; So those are the clocks from: dsi: dsi@5450000 { ... clocks = <&ccu CLK_BUS_MIPI_DSI>, <&tcon_top CLK_TCON_TOP_DSI>; clock-names = "bus", "mod"; ... }; So the "mod" clock here points to the tcon_top device, the one with the "allwinner,sun20i-d1-tcon-top" compatible string. Which is implemented by drivers/gpu/drm/sun4i/sun8i_tcon_top.c, controlled by the DRM_SUN8I_TCON_TOP Kconfig symbol. Do you have that enabled? You can check /sys/kernel/debug/clk/clk_summary (with debugfs mounted) to see what clocks are there and how they are used. Cheers, Andre > I checked the buildroot config and the CCU for sun8i DE2 is being > built and included, the registration should occur and give an > exception if it's not happening: ccu-sun8i-de2.c > <https://elixir.bootlin.com/linux/v6.6.2/source/drivers/clk/sunxi-ng/ccu-sun8i-de2.c#L263> > > mod_clk <https://elixir.bootlin.com/linux/v6.6.2/C/ident/mod_clk> = > devm_clk_get > <https://elixir.bootlin.com/linux/v6.6.2/C/ident/devm_clk_get>( > &pdev->dev, "mod"); if (IS_ERR > <https://elixir.bootlin.com/linux/v6.6.2/C/ident/IS_ERR>(mod_clk > <https://elixir.bootlin.com/linux/v6.6.2/C/ident/mod_clk>)) return > dev_err_probe > <https://elixir.bootlin.com/linux/v6.6.2/C/ident/dev_err_probe>(&pdev->dev, > PTR_ERR > <https://elixir.bootlin.com/linux/v6.6.2/C/ident/PTR_ERR>(mod_clk > <https://elixir.bootlin.com/linux/v6.6.2/C/ident/mod_clk>), "Couldn't > get mod clk\n"); > > ret = clk_prepare_enable > <https://elixir.bootlin.com/linux/v6.6.2/C/ident/clk_prepare_enable>(mod_clk > <https://elixir.bootlin.com/linux/v6.6.2/C/ident/mod_clk>); if (ret) > { dev_err > <https://elixir.bootlin.com/linux/v6.6.2/C/ident/dev_err>(&pdev->dev > , "Couldn't enable mod clk: %d\n", ret); goto err_disable_bus_clk; } > > I don't see dmesg print any clock errors, but at the same time, I > understand that linux common clock framework also won't print > anything by default. > > I can't see anything in either driver that would cause an error other > than the clock not existing, if anyone has any ideas - i'm all ears. > > At the moment I am leaning towards the clock-controller; Is there a > userspace or debug option to check (mod) clock status' under the > common clock framework? > > Thanks > -- You received this message because you are subscribed to the Google Groups "linux-sunxi" group. To unsubscribe from this group and stop receiving emails from it, send an email to linux-sunxi+unsubscr...@googlegroups.com. To view this discussion on the web, visit https://groups.google.com/d/msgid/linux-sunxi/20231227232842.5c1c9ed8%40minigeek.lan.
