[PATCH v5 07/12] phy: rockchip: samsung-hdptx: Avoid Hz<->hHz unit conversion overhead

Dmitry Baryshkov dmitry.baryshkov at linaro.org
Sun Mar 9 01:22:50 PST 2025


On Sat, 8 Mar 2025 at 14:21, Cristian Ciocaltea
<cristian.ciocaltea at collabora.com> wrote:
>
> The ropll_tmds_cfg table used to identify the configuration params for
> the supported rates expects the search key, i.e. bit_rate member of
> struct ropll_config, to be provided in hHz rather than Hz (1 hHz = 100
> Hz).  This requires multiple conversions between these units being
> performed at runtime.
>
> Improve implementation clarity and efficiency by consistently using the
> Hz unit throughout driver's internal data structures and functions.
> Also rename the rather misleading struct member.
>
> Signed-off-by: Cristian Ciocaltea <cristian.ciocaltea at collabora.com>
> ---
>  drivers/phy/rockchip/phy-rockchip-samsung-hdptx.c | 79 +++++++++++------------
>  1 file changed, 39 insertions(+), 40 deletions(-)
>
> diff --git a/drivers/phy/rockchip/phy-rockchip-samsung-hdptx.c b/drivers/phy/rockchip/phy-rockchip-samsung-hdptx.c
> index 2bf525514c1991a1299265d12e1e85f66333c604..e58a01bdb3ce82d66acdcb02c06de2816288b574 100644
> --- a/drivers/phy/rockchip/phy-rockchip-samsung-hdptx.c
> +++ b/drivers/phy/rockchip/phy-rockchip-samsung-hdptx.c
> @@ -330,7 +330,7 @@ enum dp_link_rate {
>  };
>
>  struct ropll_config {
> -       u32 bit_rate;
> +       u32 rate;

unsigned long long, please, to match the tmds_char_rate type.

>         u8 pms_mdiv;
>         u8 pms_mdiv_afc;
>         u8 pms_pdiv;
> @@ -410,45 +410,45 @@ struct rk_hdptx_phy {
>  };
>
>  static const struct ropll_config ropll_tmds_cfg[] = {
> -       { 5940000, 124, 124, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 62, 1, 16, 5, 0,
> +       { 594000000, 124, 124, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 62, 1, 16, 5, 0,

Use ULL suffix

>           1, 1, 0, 0x20, 0x0c, 1, 0x0e, 0, 0, },
> -       { 3712500, 155, 155, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 62, 1, 16, 5, 0,
> +       { 371250000, 155, 155, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 62, 1, 16, 5, 0,
>           1, 1, 0, 0x20, 0x0c, 1, 0x0e, 0, 0, },
> -       { 2970000, 124, 124, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 62, 1, 16, 5, 0,
> +       { 297000000, 124, 124, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 62, 1, 16, 5, 0,
>           1, 1, 0, 0x20, 0x0c, 1, 0x0e, 0, 0, },
> -       { 1620000, 135, 135, 1, 1, 3, 1, 1, 0, 1, 1, 1, 1, 4, 0, 3, 5, 5, 0x10,
> +       { 162000000, 135, 135, 1, 1, 3, 1, 1, 0, 1, 1, 1, 1, 4, 0, 3, 5, 5, 0x10,
>           1, 0, 0x20, 0x0c, 1, 0x0e, 0, 0, },
> -       { 1856250, 155, 155, 1, 1, 3, 1, 1, 1, 1, 1, 1, 1, 62, 1, 16, 5, 0,
> +       { 185625000, 155, 155, 1, 1, 3, 1, 1, 1, 1, 1, 1, 1, 62, 1, 16, 5, 0,
>           1, 1, 0, 0x20, 0x0c, 1, 0x0e, 0, 0, },
> -       { 1540000, 193, 193, 1, 1, 5, 1, 1, 1, 1, 1, 1, 1, 193, 1, 32, 2, 1,
> +       { 154000000, 193, 193, 1, 1, 5, 1, 1, 1, 1, 1, 1, 1, 193, 1, 32, 2, 1,
>           1, 1, 0, 0x20, 0x0c, 1, 0x0e, 0, 0, },
> -       { 1485000, 0x7b, 0x7b, 1, 1, 3, 1, 1, 1, 1, 1, 1, 1, 4, 0, 3, 5, 5,
> +       { 148500000, 0x7b, 0x7b, 1, 1, 3, 1, 1, 1, 1, 1, 1, 1, 4, 0, 3, 5, 5,
>           0x10, 1, 0, 0x20, 0x0c, 1, 0x0e, 0, 0, },
> -       { 1462500, 122, 122, 1, 1, 3, 1, 1, 1, 1, 1, 1, 1, 244, 1, 16, 2, 1, 1,
> +       { 146250000, 122, 122, 1, 1, 3, 1, 1, 1, 1, 1, 1, 1, 244, 1, 16, 2, 1, 1,
>           1, 0, 0x20, 0x0c, 1, 0x0e, 0, 0, },
> -       { 1190000, 149, 149, 1, 1, 5, 1, 1, 1, 1, 1, 1, 1, 149, 1, 16, 2, 1, 1,
> +       { 119000000, 149, 149, 1, 1, 5, 1, 1, 1, 1, 1, 1, 1, 149, 1, 16, 2, 1, 1,
>           1, 0, 0x20, 0x0c, 1, 0x0e, 0, 0, },
> -       { 1065000, 89, 89, 1, 1, 3, 1, 1, 1, 1, 1, 1, 1, 89, 1, 16, 1, 0, 1,
> +       { 106500000, 89, 89, 1, 1, 3, 1, 1, 1, 1, 1, 1, 1, 89, 1, 16, 1, 0, 1,
>           1, 0, 0x20, 0x0c, 1, 0x0e, 0, 0, },
> -       { 1080000, 135, 135, 1, 1, 5, 1, 1, 0, 1, 0, 1, 1, 0x9, 0, 0x05, 0,
> +       { 108000000, 135, 135, 1, 1, 5, 1, 1, 0, 1, 0, 1, 1, 0x9, 0, 0x05, 0,
>           0x14, 0x18, 1, 0, 0x20, 0x0c, 1, 0x0e, 0, 0, },
> -       { 855000, 214, 214, 1, 1, 11, 1, 1, 1, 1, 1, 1, 1, 214, 1, 16, 2, 1,
> +       { 85500000, 214, 214, 1, 1, 11, 1, 1, 1, 1, 1, 1, 1, 214, 1, 16, 2, 1,
>           1, 1, 0, 0x20, 0x0c, 1, 0x0e, 0, 0, },
> -       { 835000, 105, 105, 1, 1, 5, 1, 1, 1, 1, 1, 1, 1, 42, 1, 16, 1, 0,
> +       { 83500000, 105, 105, 1, 1, 5, 1, 1, 1, 1, 1, 1, 1, 42, 1, 16, 1, 0,
>           1, 1, 0, 0x20, 0x0c, 1, 0x0e, 0, 0, },
> -       { 928125, 155, 155, 1, 1, 7, 1, 1, 1, 1, 1, 1, 1, 62, 1, 16, 5, 0,
> +       { 92812500, 155, 155, 1, 1, 7, 1, 1, 1, 1, 1, 1, 1, 62, 1, 16, 5, 0,
>           1, 1, 0, 0x20, 0x0c, 1, 0x0e, 0, 0, },
> -       { 742500, 124, 124, 1, 1, 7, 1, 1, 1, 1, 1, 1, 1, 62, 1, 16, 5, 0,
> +       { 74250000, 124, 124, 1, 1, 7, 1, 1, 1, 1, 1, 1, 1, 62, 1, 16, 5, 0,
>           1, 1, 0, 0x20, 0x0c, 1, 0x0e, 0, 0, },
> -       { 650000, 162, 162, 1, 1, 11, 1, 1, 1, 1, 1, 1, 1, 54, 0, 16, 4, 1,
> +       { 65000000, 162, 162, 1, 1, 11, 1, 1, 1, 1, 1, 1, 1, 54, 0, 16, 4, 1,
>           1, 1, 0, 0x20, 0x0c, 1, 0x0e, 0, 0, },
> -       { 337500, 0x70, 0x70, 1, 1, 0xf, 1, 1, 1, 1, 1, 1, 1, 0x2, 0, 0x01, 5,
> +       { 33750000, 0x70, 0x70, 1, 1, 0xf, 1, 1, 1, 1, 1, 1, 1, 0x2, 0, 0x01, 5,
>           1, 1, 1, 0, 0x20, 0x0c, 1, 0x0e, 0, 0, },
> -       { 400000, 100, 100, 1, 1, 11, 1, 1, 0, 1, 0, 1, 1, 0x9, 0, 0x05, 0,
> +       { 40000000, 100, 100, 1, 1, 11, 1, 1, 0, 1, 0, 1, 1, 0x9, 0, 0x05, 0,
>           0x14, 0x18, 1, 0, 0x20, 0x0c, 1, 0x0e, 0, 0, },
> -       { 270000, 0x5a, 0x5a, 1, 1, 0xf, 1, 1, 0, 1, 0, 1, 1, 0x9, 0, 0x05, 0,
> +       { 27000000, 0x5a, 0x5a, 1, 1, 0xf, 1, 1, 0, 1, 0, 1, 1, 0x9, 0, 0x05, 0,
>           0x14, 0x18, 1, 0, 0x20, 0x0c, 1, 0x0e, 0, 0, },
> -       { 251750, 84, 84, 1, 1, 0xf, 1, 1, 1, 1, 1, 1, 1, 168, 1, 16, 4, 1, 1,
> +       { 25175000, 84, 84, 1, 1, 0xf, 1, 1, 1, 1, 1, 1, 1, 168, 1, 16, 4, 1, 1,
>           1, 0, 0x20, 0x0c, 1, 0x0e, 0, 0, },
>  };
>
> @@ -894,10 +894,10 @@ static void rk_hdptx_phy_disable(struct rk_hdptx_phy *hdptx)
>         regmap_write(hdptx->grf, GRF_HDPTX_CON0, val);
>  }
>
> -static bool rk_hdptx_phy_clk_pll_calc(unsigned int data_rate,
> +static bool rk_hdptx_phy_clk_pll_calc(unsigned long rate,

here and further, unsigned long long
Also, is it tmds_char_rate?

>                                       struct ropll_config *cfg)
>  {
> -       const unsigned int fout = data_rate / 2, fref = 24000;
> +       const unsigned int fout = rate / 200, fref = 24000;
>         unsigned long k = 0, lc, k_sub, lc_sub;
>         unsigned int fvco, sdc;
>         u32 mdiv, sdiv, n = 8;

-- 
With best wishes
Dmitry



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