| Message ID | 20210713232510.3057750-4-martin.blumenstingl@googlemail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | clk: meson8b: video clock tree fixes and making it mutable | expand |
On Wed 14 Jul 2021 at 01:25, Martin Blumenstingl <martin.blumenstingl@googlemail.com> wrote: > The 3.10 vendor kernel uses only specific HDMI PLL M/N parameter > combinations. The PLL won't lock for values smaller than 50 if the > internal doubling (which is yet unknown how to use it) is disabled. > However, when this doubling is enabled then the values smaller than 50 > will lock just fine. The only restriction for values greater than 50 is > that the resulting frequency must not exceed the 3.0GHz limit. Hum, it's not the first time we have that type of issue. I'm thinking that, instead of using mult_range, we should probably have min and max output frequencies . The datasheet usually documents these values for PLL DCO. Something to think about ... > > These values are taken from the endlessm 3.10 kernel which includes > additional M/N combinations for some VESA and 75Hz display modes. > > Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> > --- > drivers/clk/meson/meson8b.c | 22 ++++++++++++++++++++++ > 1 file changed, 22 insertions(+) > > diff --git a/drivers/clk/meson/meson8b.c b/drivers/clk/meson/meson8b.c > index 9ccffbfe44e5..8f29d26ed726 100644 > --- a/drivers/clk/meson/meson8b.c > +++ b/drivers/clk/meson/meson8b.c > @@ -118,6 +118,27 @@ static struct clk_regmap meson8b_fixed_pll = { > }, > }; > > +static const struct pll_params_table hdmi_pll_params_table[] = { > + PLL_PARAMS(40, 1), > + PLL_PARAMS(42, 1), > + PLL_PARAMS(44, 1), > + PLL_PARAMS(45, 1), > + PLL_PARAMS(49, 1), > + PLL_PARAMS(52, 1), > + PLL_PARAMS(54, 1), > + PLL_PARAMS(56, 1), > + PLL_PARAMS(59, 1), > + PLL_PARAMS(60, 1), > + PLL_PARAMS(61, 1), > + PLL_PARAMS(62, 1), > + PLL_PARAMS(64, 1), > + PLL_PARAMS(66, 1), > + PLL_PARAMS(68, 1), > + PLL_PARAMS(71, 1), > + PLL_PARAMS(82, 1), > + { /* sentinel */ } > +}; > + > static struct clk_regmap meson8b_hdmi_pll_dco = { > .data = &(struct meson_clk_pll_data){ > .en = { > @@ -150,6 +171,7 @@ static struct clk_regmap meson8b_hdmi_pll_dco = { > .shift = 29, > .width = 1, > }, > + .table = hdmi_pll_params_table, > }, > .hw.init = &(struct clk_init_data){ > /* sometimes also called "HPLL" or "HPLL PLL" */
diff --git a/drivers/clk/meson/meson8b.c b/drivers/clk/meson/meson8b.c index 9ccffbfe44e5..8f29d26ed726 100644 --- a/drivers/clk/meson/meson8b.c +++ b/drivers/clk/meson/meson8b.c @@ -118,6 +118,27 @@ static struct clk_regmap meson8b_fixed_pll = { }, }; +static const struct pll_params_table hdmi_pll_params_table[] = { + PLL_PARAMS(40, 1), + PLL_PARAMS(42, 1), + PLL_PARAMS(44, 1), + PLL_PARAMS(45, 1), + PLL_PARAMS(49, 1), + PLL_PARAMS(52, 1), + PLL_PARAMS(54, 1), + PLL_PARAMS(56, 1), + PLL_PARAMS(59, 1), + PLL_PARAMS(60, 1), + PLL_PARAMS(61, 1), + PLL_PARAMS(62, 1), + PLL_PARAMS(64, 1), + PLL_PARAMS(66, 1), + PLL_PARAMS(68, 1), + PLL_PARAMS(71, 1), + PLL_PARAMS(82, 1), + { /* sentinel */ } +}; + static struct clk_regmap meson8b_hdmi_pll_dco = { .data = &(struct meson_clk_pll_data){ .en = { @@ -150,6 +171,7 @@ static struct clk_regmap meson8b_hdmi_pll_dco = { .shift = 29, .width = 1, }, + .table = hdmi_pll_params_table, }, .hw.init = &(struct clk_init_data){ /* sometimes also called "HPLL" or "HPLL PLL" */
The 3.10 vendor kernel uses only specific HDMI PLL M/N parameter combinations. The PLL won't lock for values smaller than 50 if the internal doubling (which is yet unknown how to use it) is disabled. However, when this doubling is enabled then the values smaller than 50 will lock just fine. The only restriction for values greater than 50 is that the resulting frequency must not exceed the 3.0GHz limit. These values are taken from the endlessm 3.10 kernel which includes additional M/N combinations for some VESA and 75Hz display modes. Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> --- drivers/clk/meson/meson8b.c | 22 ++++++++++++++++++++++ 1 file changed, 22 insertions(+)