Re: [PATCH 0/6] clk: meson8b: video clock tree fixes and making it mutable

[Jerome Brunet]

On Wed 14 Jul 2021 at 01:25, Martin Blumenstingl <martin.blumenstingl@xxxxxxxxxxxxxx> wrote:

> The first two patches in this series are small fixes before we can
> actually make the video clock tree mutable. One patch adds
> CLK_SET_RATE_NO_REPARENT for better rate control and the other adds
> a missing clock gate.
>
> The third and fourth patch are targeting the HDMI PLL. Add the known
> working M/N combinations. Also this PLL has some special "doubling"
> setting, which is calculated like this:
>   OUTPUT = (IN * M / N + FRAC) * 2
> Since not all register bits are known we use a copy of the 2970/2975MHz
> magic register values from the vendor driver.
>
> The fifth patch makes the clocks in the video clock tree mutable. The
> final patch in this series exports the clocks needed for rate control.
>
> For reference, this is the .dts definition for the Meson8b VPU. The
> code for the VPU driver is unfortunately not ready for upstreaming yet.
> However, I have tested with all resolutions my monitor supports and the
> clock settings are all applied correctly.
>     vpu: vpu@100000 {
>       compatible = "amlogic,meson8b-vpu";
>
>       reg = <0x100000 0x10000>;
>       reg-names = "vpu";
>
>       interrupts = <GIC_SPI 3 IRQ_TYPE_EDGE_RISING>;
>
>       amlogic,canvas = <&canvas>;
>       amlogic,hhi-sysctrl = <&hhi>;
>
>       /*
>        * The VCLK{,2}_IN path always needs to derived from
>        * the CLKID_VID_PLL_FINAL_DIV so other clocks like
>        * MPLL1 are not used (MPLL1 is reserved for audio
>        * purposes).
>        */
>       assigned-clocks = <&clkc CLKID_VCLK_IN_SEL>,
>                         <&clkc CLKID_VCLK2_IN_SEL>;
>       assigned-clock-parents = <&clkc CLKID_VID_PLL_FINAL_DIV>,
>                                <&clkc CLKID_VID_PLL_FINAL_DIV>;
>
>       clocks = <&clkc CLKID_VPU_INTR>,
>                <&clkc CLKID_HDMI_INTR_SYNC>,
>                <&clkc CLKID_GCLK_VENCI_INT>,
>                <&clkc CLKID_HDMI_PLL_HDMI_OUT>,
>                <&clkc CLKID_HDMI_TX_PIXEL>,
>                <&clkc CLKID_CTS_ENCP>,
>                <&clkc CLKID_CTS_ENCI>,
>                <&clkc CLKID_CTS_ENCT>,
>                <&clkc CLKID_CTS_ENCL>,
>                <&clkc CLKID_CTS_VDAC0>;
>       clock-names = "vpu_intr",
>                     "hdmi_intr_sync",
>                     "venci_int",
>                     "tmds",
>                     "hdmi_tx_pixel",
>                     "cts_encp",
>                     "cts_enci",
>                     "cts_enct",
>                     "cts_encl",
>                     "cts_vdac0";
>
>       resets = <&clkc CLKC_RESET_VID_DIVIDER_CNTL_RESET_N_PRE>,
>                <&clkc CLKC_RESET_VID_DIVIDER_CNTL_RESET_N_POST>,
>                <&clkc CLKC_RESET_VID_DIVIDER_CNTL_SOFT_RESET_PRE>,
>                <&clkc CLKC_RESET_VID_DIVIDER_CNTL_SOFT_RESET_POST>;
>       reset-names = "vid_pll_pre",
>                     "vid_pll_post",
>                     "vid_pll_soft_pre",
>                     "vid_pll_soft_post";
>
>       power-domains = <&pwrc PWRC_MESON8_VPU_ID>;
>
>       nvmem-cells = <&cvbs_trimming>;
>       nvmem-cell-names = "cvbs_trimming";
>
>       #address-cells = <1>;
>       #size-cells = <0>;
>
>       #sound-dai-cells = <0>;
>       sound-name-prefix = "HDMITX";
>
>       /* CVBS VDAC output port */
>       cvbs_vdac_port: port@0 {
>         reg = <0>;
>       };
>
>       /* HDMI-TX output port */
>       hdmi_tx_port: port@1 {
>         reg = <1>;
>
>         hdmi_tx_out: endpoint {
>           remote-endpoint = <&hdmi_tx_in>;
>         };
>       };
>     };
>
>
> Martin Blumenstingl (6):
>   clk: meson: meson8b: Use CLK_SET_RATE_NO_REPARENT for vclk{,2}_in_sel
>   clk: meson: meson8b: Add the vid_pll_lvds_en gate clock
>   clk: meson: meson8b: Add the HDMI PLL M/N parameters
>   clk: meson: meson8b: Initialize the HDMI PLL registers
>   clk: meson: meson8b: Make the video clock trees mutable
>   clk: meson: meson8b: Export the video clocks
>
>  drivers/clk/meson/meson8b.c              | 163 +++++++++++++++++------
>  drivers/clk/meson/meson8b.h              |  26 ++--
>  include/dt-bindings/clock/meson8b-clkc.h |  10 ++
>  3 files changed, 143 insertions(+), 56 deletions(-)

Applied, Thx