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From: Maxime Jourdan <mjourdan@baylibre.com>
To: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Cc: devicetree@vger.kernel.org,
	Neil Armstrong <narmstrong@baylibre.com>,
	linux-kernel@vger.kernel.org, linux-amlogic@lists.infradead.org,
	linux-clk@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
	Jerome Brunet <jbrunet@baylibre.com>
Subject: Re: [PATCH 2/2] clk: meson: meson8b: add the video decoder clock trees
Date: Wed, 20 Mar 2019 12:16:19 +0100	[thread overview]
Message-ID: <CAMO6nawKpBRrp0oBtrGY8KskD6tUX9ZCNeDqSGPB-kMnm27HnA@mail.gmail.com> (raw)
In-Reply-To: <20190319220012.31065-3-martin.blumenstingl@googlemail.com>

Hi Martin, thanks for looking into the video decoder for meson8!
On Tue, Mar 19, 2019 at 11:00 PM Martin Blumenstingl
<martin.blumenstingl@googlemail.com> wrote:
>
> This adds the four video decoder clock trees.
>
> VDEC_1 is split into two paths on Meson8b and Meson8m2:
> - input mux called "vdec_1_sel"
> - two dividers ("vdec_1_1_div" and "vdec_1_2_div") and gates ("vdec_1_1"
>   and "vdec_1_2")
> - and an output mux (probably glitch-free) called "vdec_1"

Yes, all vdec clocks have a glitch-free mux to be able to safely
adjust the frequency on the fly, although in practice it's barely
used.

> On Meson8 the VDEC_1 tree is simpler because there's only one path:
> - input mux called "vdec_1_sel"
> - divider ("vdec_1_1_div") and gate ("vdec_1_1")
> - (the gate is used as output directly, there's no mux)
>
> The VDEC_HCODEC and VDEC_2 clocks are simple composite clocks each
> consisting of an input mux, divider and a gate.
>
> The VDEC_HEVC clock seems to have two paths similar to the VDEC_1 clock.
> However, the register offsets of the second clock path is not known.
> Amlogic's 3.10 kernel (which is used as reference) sets
> HHI_VDEC2_CLK_CNTL[31] to 1 before changing the VDEC_HEVC clock and back
> to 0 afterwards. For now, leave a TODO comment and only add the first
> path.
>

Looking at aml-3.10/drivers/amlogic/amports/m8b/vdec_clk.c, it's weird
indeed. They seem to copy the divider's value to the same place
(HHI_VDEC2_CLK_CNTL[16~23]), and the only thing that stands out is
enabling HHI_VDEC2_CLK_CNTL[31].

Then again they don't make use of that codepath at all, so who knows..

> Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
> ---
>  drivers/clk/meson/meson8b.c | 312 ++++++++++++++++++++++++++++++++++++
>  drivers/clk/meson/meson8b.h |  17 +-
>  2 files changed, 328 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/clk/meson/meson8b.c b/drivers/clk/meson/meson8b.c
> index 8e091c2d10e6..37cf0f01bb5d 100644
> --- a/drivers/clk/meson/meson8b.c
> +++ b/drivers/clk/meson/meson8b.c
> @@ -1902,6 +1902,257 @@ static struct clk_regmap meson8b_vpu = {
>         },
>  };
>
> +static const char * const meson8b_vdec_parent_names[] = {
> +       "fclk_div4", "fclk_div3", "fclk_div5", "fclk_div7", "mpll2", "mpll1"
> +};
> +
> +static struct clk_regmap meson8b_vdec_1_sel = {
> +       .data = &(struct clk_regmap_mux_data){
> +               .offset = HHI_VDEC_CLK_CNTL,
> +               .mask = 0x3,
> +               .shift = 9,
> +               .flags = CLK_MUX_ROUND_CLOSEST,
> +       },
> +       .hw.init = &(struct clk_init_data){
> +               .name = "vdec_1_sel",
> +               .ops = &clk_regmap_mux_ops,
> +               .parent_names = meson8b_vdec_parent_names,
> +               .num_parents = ARRAY_SIZE(meson8b_vdec_parent_names),
> +               .flags = CLK_SET_RATE_PARENT,
> +       },
> +};
> +
> +static struct clk_regmap meson8b_vdec_1_1_div = {
> +       .data = &(struct clk_regmap_div_data){
> +               .offset = HHI_VDEC_CLK_CNTL,
> +               .shift = 0,
> +               .width = 7,
> +               .flags = CLK_DIVIDER_ROUND_CLOSEST,
> +       },
> +       .hw.init = &(struct clk_init_data){
> +               .name = "vdec_1_1_div",
> +               .ops = &clk_regmap_divider_ops,
> +               .parent_names = (const char *[]){ "vdec_1_sel" },
> +               .num_parents = 1,
> +               .flags = CLK_SET_RATE_PARENT,
> +       },
> +};
> +
> +static struct clk_regmap meson8b_vdec_1_1 = {
> +       .data = &(struct clk_regmap_gate_data){
> +               .offset = HHI_VDEC_CLK_CNTL,
> +               .bit_idx = 8,
> +       },
> +       .hw.init = &(struct clk_init_data) {
> +               .name = "vdec_1_1",
> +               .ops = &clk_regmap_gate_ops,
> +               .parent_names = (const char *[]){ "vdec_1_1_div" },
> +               .num_parents = 1,
> +               .flags = CLK_SET_RATE_PARENT,
> +       },
> +};
> +
> +static struct clk_regmap meson8b_vdec_1_2_div = {
> +       .data = &(struct clk_regmap_div_data){
> +               .offset = HHI_VDEC3_CLK_CNTL,
> +               .shift = 0,
> +               .width = 7,
> +               .flags = CLK_DIVIDER_ROUND_CLOSEST,
> +       },
> +       .hw.init = &(struct clk_init_data){
> +               .name = "vdec_1_2_div",
> +               .ops = &clk_regmap_divider_ops,
> +               .parent_names = (const char *[]){ "vdec_1_sel" },
> +               .num_parents = 1,
> +               .flags = CLK_SET_RATE_PARENT,
> +       },
> +};
> +
> +static struct clk_regmap meson8b_vdec_1_2 = {
> +       .data = &(struct clk_regmap_gate_data){
> +               .offset = HHI_VDEC3_CLK_CNTL,
> +               .bit_idx = 8,
> +       },
> +       .hw.init = &(struct clk_init_data) {
> +               .name = "vdec_1_2",
> +               .ops = &clk_regmap_gate_ops,
> +               .parent_names = (const char *[]){ "vdec_1_2_div" },
> +               .num_parents = 1,
> +               .flags = CLK_SET_RATE_PARENT,
> +       },
> +};
> +
> +static struct clk_regmap meson8b_vdec_1 = {
> +       .data = &(struct clk_regmap_mux_data){
> +               .offset = HHI_VDEC3_CLK_CNTL,
> +               .mask = 0x1,
> +               .shift = 15,
> +               .flags = CLK_MUX_ROUND_CLOSEST,
> +       },
> +       .hw.init = &(struct clk_init_data){
> +               .name = "vdec_1",
> +               .ops = &clk_regmap_mux_ops,
> +               .parent_names = (const char *[]){ "vdec_1_1", "vdec_1_2" },
> +               .num_parents = 2,
> +               .flags = CLK_SET_RATE_PARENT,
> +       },
> +};
> +
> +static struct clk_regmap meson8b_vdec_hcodec_sel = {
> +       .data = &(struct clk_regmap_mux_data){
> +               .offset = HHI_VDEC_CLK_CNTL,
> +               .mask = 0x3,
> +               .shift = 25,
> +               .flags = CLK_MUX_ROUND_CLOSEST,
> +       },
> +       .hw.init = &(struct clk_init_data){
> +               .name = "vdec_hcodec_sel",
> +               .ops = &clk_regmap_mux_ops,
> +               .parent_names = meson8b_vdec_parent_names,
> +               .num_parents = ARRAY_SIZE(meson8b_vdec_parent_names),
> +               .flags = CLK_SET_RATE_PARENT,
> +       },
> +};
> +
> +static struct clk_regmap meson8b_vdec_hcodec_div = {
> +       .data = &(struct clk_regmap_div_data){
> +               .offset = HHI_VDEC_CLK_CNTL,
> +               .shift = 16,
> +               .width = 7,
> +               .flags = CLK_DIVIDER_ROUND_CLOSEST,
> +       },
> +       .hw.init = &(struct clk_init_data){
> +               .name = "vdec_hcodec_div",
> +               .ops = &clk_regmap_divider_ops,
> +               .parent_names = (const char *[]){ "vdec_hcodec_sel" },
> +               .num_parents = 1,
> +               .flags = CLK_SET_RATE_PARENT,
> +       },
> +};
> +
> +static struct clk_regmap meson8b_vdec_hcodec = {
> +       .data = &(struct clk_regmap_gate_data){
> +               .offset = HHI_VDEC_CLK_CNTL,
> +               .bit_idx = 24,
> +       },
> +       .hw.init = &(struct clk_init_data) {
> +               .name = "vdec_hcodec",
> +               .ops = &clk_regmap_gate_ops,
> +               .parent_names = (const char *[]){ "vdec_hcodec_div" },
> +               .num_parents = 1,
> +               .flags = CLK_SET_RATE_PARENT,
> +       },
> +};
> +
> +static struct clk_regmap meson8b_vdec_2_sel = {
> +       .data = &(struct clk_regmap_mux_data){
> +               .offset = HHI_VDEC2_CLK_CNTL,
> +               .mask = 0x3,
> +               .shift = 9,
> +               .flags = CLK_MUX_ROUND_CLOSEST,
> +       },
> +       .hw.init = &(struct clk_init_data){
> +               .name = "vdec_2_sel",
> +               .ops = &clk_regmap_mux_ops,
> +               .parent_names = meson8b_vdec_parent_names,
> +               .num_parents = ARRAY_SIZE(meson8b_vdec_parent_names),
> +               .flags = CLK_SET_RATE_PARENT,
> +       },
> +};
> +
> +static struct clk_regmap meson8b_vdec_2_div = {
> +       .data = &(struct clk_regmap_div_data){
> +               .offset = HHI_VDEC2_CLK_CNTL,
> +               .shift = 0,
> +               .width = 7,
> +               .flags = CLK_DIVIDER_ROUND_CLOSEST,
> +       },
> +       .hw.init = &(struct clk_init_data){
> +               .name = "vdec_2_div",
> +               .ops = &clk_regmap_divider_ops,
> +               .parent_names = (const char *[]){ "vdec_2_sel" },
> +               .num_parents = 1,
> +               .flags = CLK_SET_RATE_PARENT,
> +       },
> +};
> +
> +static struct clk_regmap meson8b_vdec_2 = {
> +       .data = &(struct clk_regmap_gate_data){
> +               .offset = HHI_VDEC2_CLK_CNTL,
> +               .bit_idx = 8,
> +       },
> +       .hw.init = &(struct clk_init_data) {
> +               .name = "vdec_2",
> +               .ops = &clk_regmap_gate_ops,
> +               .parent_names = (const char *[]){ "vdec_2_div" },
> +               .num_parents = 1,
> +               .flags = CLK_SET_RATE_PARENT,
> +       },
> +};
> +
> +static struct clk_regmap meson8b_vdec_hevc_sel = {
> +       .data = &(struct clk_regmap_mux_data){
> +               .offset = HHI_VDEC2_CLK_CNTL,
> +               .mask = 0x3,
> +               .shift = 25,
> +               .flags = CLK_MUX_ROUND_CLOSEST,
> +       },
> +       .hw.init = &(struct clk_init_data){
> +               .name = "vdec_hevc_sel",
> +               .ops = &clk_regmap_mux_ops,
> +               .parent_names = meson8b_vdec_parent_names,
> +               .num_parents = ARRAY_SIZE(meson8b_vdec_parent_names),
> +               .flags = CLK_SET_RATE_PARENT,
> +       },
> +};
> +
> +static struct clk_regmap meson8b_vdec_hevc_div = {
> +       .data = &(struct clk_regmap_div_data){
> +               .offset = HHI_VDEC2_CLK_CNTL,
> +               .shift = 16,
> +               .width = 7,
> +               .flags = CLK_DIVIDER_ROUND_CLOSEST,
> +       },
> +       .hw.init = &(struct clk_init_data){
> +               .name = "vdec_hevc_div",
> +               .ops = &clk_regmap_divider_ops,
> +               .parent_names = (const char *[]){ "vdec_hevc_sel" },
> +               .num_parents = 1,
> +               .flags = CLK_SET_RATE_PARENT,
> +       },
> +};
> +
> +static struct clk_regmap meson8b_vdec_hevc_en = {
> +       .data = &(struct clk_regmap_gate_data){
> +               .offset = HHI_VDEC2_CLK_CNTL,
> +               .bit_idx = 24,
> +       },
> +       .hw.init = &(struct clk_init_data) {
> +               .name = "vdec_hevc_en",
> +               .ops = &clk_regmap_gate_ops,
> +               .parent_names = (const char *[]){ "vdec_hevc_div" },
> +               .num_parents = 1,
> +               .flags = CLK_SET_RATE_PARENT,
> +       },
> +};
> +
> +static struct clk_regmap meson8b_vdec_hevc = {
> +       .data = &(struct clk_regmap_mux_data){
> +               .offset = HHI_VDEC2_CLK_CNTL,
> +               .mask = 0x1,
> +               .shift = 31,
> +               .flags = CLK_MUX_ROUND_CLOSEST,
> +       },
> +       .hw.init = &(struct clk_init_data){
> +               .name = "vdec_hevc",
> +               .ops = &clk_regmap_mux_ops,
> +               /* TODO: The second parent is currently unknown */
> +               .parent_names = (const char *[]){ "vdec_hevc_en" },
> +               .num_parents = 1,
> +               .flags = CLK_SET_RATE_PARENT,
> +       },
> +};
> +
>  /* Everything Else (EE) domain gates */
>
>  static MESON_GATE(meson8b_ddr, HHI_GCLK_MPEG0, 0);
> @@ -2168,6 +2419,19 @@ static struct clk_hw_onecell_data meson8_hw_onecell_data = {
>                 [CLKID_VPU_0_SEL]           = &meson8b_vpu_0_sel.hw,
>                 [CLKID_VPU_0_DIV]           = &meson8b_vpu_0_div.hw,
>                 [CLKID_VPU]                 = &meson8b_vpu_0.hw,
> +               [CLKID_VDEC_1_SEL]          = &meson8b_vdec_1_sel.hw,
> +               [CLKID_VDEC_1_1_DIV]        = &meson8b_vdec_1_1_div.hw,
> +               [CLKID_VDEC_1]              = &meson8b_vdec_1_1.hw,
> +               [CLKID_VDEC_HCODEC_SEL]     = &meson8b_vdec_hcodec_sel.hw,
> +               [CLKID_VDEC_HCODEC_DIV]     = &meson8b_vdec_hcodec_div.hw,
> +               [CLKID_VDEC_HCODEC]         = &meson8b_vdec_hcodec.hw,
> +               [CLKID_VDEC_2_SEL]          = &meson8b_vdec_2_sel.hw,
> +               [CLKID_VDEC_2_DIV]          = &meson8b_vdec_2_div.hw,
> +               [CLKID_VDEC_2]              = &meson8b_vdec_2.hw,
> +               [CLKID_VDEC_HEVC_SEL]       = &meson8b_vdec_hevc_sel.hw,
> +               [CLKID_VDEC_HEVC_DIV]       = &meson8b_vdec_hevc_div.hw,
> +               [CLKID_VDEC_HEVC_EN]        = &meson8b_vdec_hevc_en.hw,
> +               [CLKID_VDEC_HEVC]           = &meson8b_vdec_hevc.hw,
>                 [CLK_NR_CLKS]               = NULL,
>         },
>         .num = CLK_NR_CLKS,
> @@ -2361,6 +2625,22 @@ static struct clk_hw_onecell_data meson8b_hw_onecell_data = {
>                 [CLKID_VPU_1_DIV]           = &meson8b_vpu_1_div.hw,
>                 [CLKID_VPU_1]               = &meson8b_vpu_1.hw,
>                 [CLKID_VPU]                 = &meson8b_vpu.hw,
> +               [CLKID_VDEC_1_SEL]          = &meson8b_vdec_1_sel.hw,
> +               [CLKID_VDEC_1_1_DIV]        = &meson8b_vdec_1_1_div.hw,
> +               [CLKID_VDEC_1_1]            = &meson8b_vdec_1_1.hw,
> +               [CLKID_VDEC_1_2_DIV]        = &meson8b_vdec_1_2_div.hw,
> +               [CLKID_VDEC_1_2]            = &meson8b_vdec_1_2.hw,
> +               [CLKID_VDEC_1]              = &meson8b_vdec_1.hw,
> +               [CLKID_VDEC_HCODEC_SEL]     = &meson8b_vdec_hcodec_sel.hw,
> +               [CLKID_VDEC_HCODEC_DIV]     = &meson8b_vdec_hcodec_div.hw,
> +               [CLKID_VDEC_HCODEC]         = &meson8b_vdec_hcodec.hw,
> +               [CLKID_VDEC_2_SEL]          = &meson8b_vdec_2_sel.hw,
> +               [CLKID_VDEC_2_DIV]          = &meson8b_vdec_2_div.hw,
> +               [CLKID_VDEC_2]              = &meson8b_vdec_2.hw,
> +               [CLKID_VDEC_HEVC_SEL]       = &meson8b_vdec_hevc_sel.hw,
> +               [CLKID_VDEC_HEVC_DIV]       = &meson8b_vdec_hevc_div.hw,
> +               [CLKID_VDEC_HEVC_EN]        = &meson8b_vdec_hevc_en.hw,
> +               [CLKID_VDEC_HEVC]           = &meson8b_vdec_hevc.hw,
>                 [CLK_NR_CLKS]               = NULL,
>         },
>         .num = CLK_NR_CLKS,
> @@ -2556,6 +2836,22 @@ static struct clk_hw_onecell_data meson8m2_hw_onecell_data = {
>                 [CLKID_VPU_1_DIV]           = &meson8b_vpu_1_div.hw,
>                 [CLKID_VPU_1]               = &meson8b_vpu_1.hw,
>                 [CLKID_VPU]                 = &meson8b_vpu.hw,
> +               [CLKID_VDEC_1_SEL]          = &meson8b_vdec_1_sel.hw,
> +               [CLKID_VDEC_1_1_DIV]        = &meson8b_vdec_1_1_div.hw,
> +               [CLKID_VDEC_1_1]            = &meson8b_vdec_1_1.hw,
> +               [CLKID_VDEC_1_2_DIV]        = &meson8b_vdec_1_2_div.hw,
> +               [CLKID_VDEC_1_2]            = &meson8b_vdec_1_2.hw,
> +               [CLKID_VDEC_1]              = &meson8b_vdec_1.hw,
> +               [CLKID_VDEC_HCODEC_SEL]     = &meson8b_vdec_hcodec_sel.hw,
> +               [CLKID_VDEC_HCODEC_DIV]     = &meson8b_vdec_hcodec_div.hw,
> +               [CLKID_VDEC_HCODEC]         = &meson8b_vdec_hcodec.hw,
> +               [CLKID_VDEC_2_SEL]          = &meson8b_vdec_2_sel.hw,
> +               [CLKID_VDEC_2_DIV]          = &meson8b_vdec_2_div.hw,
> +               [CLKID_VDEC_2]              = &meson8b_vdec_2.hw,
> +               [CLKID_VDEC_HEVC_SEL]       = &meson8b_vdec_hevc_sel.hw,
> +               [CLKID_VDEC_HEVC_DIV]       = &meson8b_vdec_hevc_div.hw,
> +               [CLKID_VDEC_HEVC_EN]        = &meson8b_vdec_hevc_en.hw,
> +               [CLKID_VDEC_HEVC]           = &meson8b_vdec_hevc.hw,
>                 [CLK_NR_CLKS]               = NULL,
>         },
>         .num = CLK_NR_CLKS,
> @@ -2729,6 +3025,22 @@ static struct clk_regmap *const meson8b_clk_regmaps[] = {
>         &meson8b_vpu_1_div,
>         &meson8b_vpu_1,
>         &meson8b_vpu,
> +       &meson8b_vdec_1_sel,
> +       &meson8b_vdec_1_1_div,
> +       &meson8b_vdec_1_1,
> +       &meson8b_vdec_1_2_div,
> +       &meson8b_vdec_1_2,
> +       &meson8b_vdec_1,
> +       &meson8b_vdec_hcodec_sel,
> +       &meson8b_vdec_hcodec_div,
> +       &meson8b_vdec_hcodec,
> +       &meson8b_vdec_2_sel,
> +       &meson8b_vdec_2_div,
> +       &meson8b_vdec_2,
> +       &meson8b_vdec_hevc_sel,
> +       &meson8b_vdec_hevc_div,
> +       &meson8b_vdec_hevc_en,
> +       &meson8b_vdec_hevc,
>  };
>
>  static const struct meson8b_clk_reset_line {
> diff --git a/drivers/clk/meson/meson8b.h b/drivers/clk/meson/meson8b.h
> index e775f91ccce9..ed37196187e6 100644
> --- a/drivers/clk/meson/meson8b.h
> +++ b/drivers/clk/meson/meson8b.h
> @@ -37,6 +37,9 @@
>  #define HHI_MALI_CLK_CNTL              0x1b0 /* 0x6c offset in data sheet */
>  #define HHI_VPU_CLK_CNTL               0x1bc /* 0x6f offset in data sheet */
>  #define HHI_HDMI_CLK_CNTL              0x1cc /* 0x73 offset in data sheet */
> +#define HHI_VDEC_CLK_CNTL              0x1e0 /* 0x78 offset in data sheet */
> +#define HHI_VDEC2_CLK_CNTL             0x1e4 /* 0x79 offset in data sheet */
> +#define HHI_VDEC3_CLK_CNTL             0x1e8 /* 0x7a offset in data sheet */
>  #define HHI_NAND_CLK_CNTL              0x25c /* 0x97 offset in data sheet */
>  #define HHI_MPLL_CNTL                  0x280 /* 0xa0 offset in data sheet */
>  #define HHI_SYS_PLL_CNTL               0x300 /* 0xc0 offset in data sheet */
> @@ -156,8 +159,20 @@
>  #define CLKID_VPU_1_SEL                186
>  #define CLKID_VPU_1_DIV                187
>  #define CLKID_VPU_1            189
> +#define CLKID_VDEC_1_SEL       191
> +#define CLKID_VDEC_1_1_DIV     192
> +#define CLKID_VDEC_1_1         193
> +#define CLKID_VDEC_1_2_DIV     194
> +#define CLKID_VDEC_1_2         195

In order to make use of the glitch-free mux by the driver, shouldn't
CLKID_VDEC_1_1 and CLKID_VDEC_1_2 be exported in the bindings ?

> +#define CLKID_VDEC_HCODEC_SEL  197
> +#define CLKID_VDEC_HCODEC_DIV  198
> +#define CLKID_VDEC_2_SEL       200
> +#define CLKID_VDEC_2_DIV       201
> +#define CLKID_VDEC_HEVC_SEL    203
> +#define CLKID_VDEC_HEVC_DIV    204
> +#define CLKID_VDEC_HEVC_EN     205
>
> -#define CLK_NR_CLKS            191
> +#define CLK_NR_CLKS            207
>
>  /*
>   * include the CLKID and RESETID that have
> --
> 2.21.0
>

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  parent reply	other threads:[~2019-03-20 11:16 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-03-19 22:00 [PATCH 0/2] clk: meson8b: add the video decoder clocks Martin Blumenstingl
2019-03-19 22:00 ` [PATCH 1/2] dt-bindings: clock: meson8b: export " Martin Blumenstingl
2019-03-19 22:00 ` [PATCH 2/2] clk: meson: meson8b: add the video decoder clock trees Martin Blumenstingl
2019-03-20  8:20   ` Neil Armstrong
2019-03-20 11:16   ` Maxime Jourdan [this message]
2019-03-20 20:53     ` Martin Blumenstingl
2019-03-21 11:42       ` Maxime Jourdan

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