| Message ID | 20210926224058.1252-12-digetx@gmail.com (mailing list archive) |
|---|---|
| State | Not Applicable, archived |
| Headers | show |
| Series | NVIDIA Tegra power management patches for 5.16 | expand |
On Mon, 27 Sept 2021 at 00:42, Dmitry Osipenko <digetx@gmail.com> wrote: > > Add OPP and SoC core voltage scaling support to the display controller > driver. This is required for enabling system-wide DVFS on pre-Tegra186 > SoCs. > > Tested-by: Peter Geis <pgwipeout@gmail.com> # Ouya T30 > Tested-by: Paul Fertser <fercerpav@gmail.com> # PAZ00 T20 > Tested-by: Nicolas Chauvet <kwizart@gmail.com> # PAZ00 T20 and TK1 T124 > Tested-by: Matt Merhar <mattmerhar@protonmail.com> # Ouya T30 > Signed-off-by: Dmitry Osipenko <digetx@gmail.com> > --- > drivers/gpu/drm/tegra/dc.c | 74 ++++++++++++++++++++++++++++++++++++++ > drivers/gpu/drm/tegra/dc.h | 2 ++ > 2 files changed, 76 insertions(+) > > diff --git a/drivers/gpu/drm/tegra/dc.c b/drivers/gpu/drm/tegra/dc.c > index a29d64f87563..d4047a14e2b6 100644 > --- a/drivers/gpu/drm/tegra/dc.c > +++ b/drivers/gpu/drm/tegra/dc.c > @@ -11,9 +11,12 @@ > #include <linux/interconnect.h> > #include <linux/module.h> > #include <linux/of_device.h> > +#include <linux/pm_domain.h> > +#include <linux/pm_opp.h> > #include <linux/pm_runtime.h> > #include <linux/reset.h> > > +#include <soc/tegra/common.h> > #include <soc/tegra/pmc.h> > > #include <drm/drm_atomic.h> > @@ -1762,6 +1765,47 @@ int tegra_dc_state_setup_clock(struct tegra_dc *dc, > return 0; > } > > +static void tegra_dc_update_voltage_state(struct tegra_dc *dc, > + struct tegra_dc_state *state) > +{ > + unsigned long rate, pstate; > + struct dev_pm_opp *opp; > + int err; > + > + if (!dc->has_opp_table) > + return; > + > + /* calculate actual pixel clock rate which depends on internal divider */ > + rate = DIV_ROUND_UP(clk_get_rate(dc->clk) * 2, state->div + 2); > + > + /* find suitable OPP for the rate */ > + opp = dev_pm_opp_find_freq_ceil(dc->dev, &rate); > + > + if (opp == ERR_PTR(-ERANGE)) > + opp = dev_pm_opp_find_freq_floor(dc->dev, &rate); > + > + if (IS_ERR(opp)) { > + dev_err(dc->dev, "failed to find OPP for %luHz: %pe\n", > + rate, opp); > + return; > + } > + > + pstate = dev_pm_opp_get_required_pstate(opp, 0); > + dev_pm_opp_put(opp); > + > + /* > + * The minimum core voltage depends on the pixel clock rate (which > + * depends on internal clock divider of the CRTC) and not on the > + * rate of the display controller clock. This is why we're not using > + * dev_pm_opp_set_rate() API and instead controlling the power domain > + * directly. > + */ > + err = dev_pm_genpd_set_performance_state(dc->dev, pstate); > + if (err) > + dev_err(dc->dev, "failed to set power domain state to %lu: %d\n", > + pstate, err); Yeah, the above code looks very similar to the code I pointed to in patch6. Perhaps we need to discuss with Viresh, whether it makes sense to fold in a patch adding an opp helper function after all, to avoid the open coding. Viresh? [...] Kind regards Uffe
01.10.2021 16:27, Ulf Hansson пишет: > On Mon, 27 Sept 2021 at 00:42, Dmitry Osipenko <digetx@gmail.com> wrote: >> >> Add OPP and SoC core voltage scaling support to the display controller >> driver. This is required for enabling system-wide DVFS on pre-Tegra186 >> SoCs. >> >> Tested-by: Peter Geis <pgwipeout@gmail.com> # Ouya T30 >> Tested-by: Paul Fertser <fercerpav@gmail.com> # PAZ00 T20 >> Tested-by: Nicolas Chauvet <kwizart@gmail.com> # PAZ00 T20 and TK1 T124 >> Tested-by: Matt Merhar <mattmerhar@protonmail.com> # Ouya T30 >> Signed-off-by: Dmitry Osipenko <digetx@gmail.com> >> --- >> drivers/gpu/drm/tegra/dc.c | 74 ++++++++++++++++++++++++++++++++++++++ >> drivers/gpu/drm/tegra/dc.h | 2 ++ >> 2 files changed, 76 insertions(+) >> >> diff --git a/drivers/gpu/drm/tegra/dc.c b/drivers/gpu/drm/tegra/dc.c >> index a29d64f87563..d4047a14e2b6 100644 >> --- a/drivers/gpu/drm/tegra/dc.c >> +++ b/drivers/gpu/drm/tegra/dc.c >> @@ -11,9 +11,12 @@ >> #include <linux/interconnect.h> >> #include <linux/module.h> >> #include <linux/of_device.h> >> +#include <linux/pm_domain.h> >> +#include <linux/pm_opp.h> >> #include <linux/pm_runtime.h> >> #include <linux/reset.h> >> >> +#include <soc/tegra/common.h> >> #include <soc/tegra/pmc.h> >> >> #include <drm/drm_atomic.h> >> @@ -1762,6 +1765,47 @@ int tegra_dc_state_setup_clock(struct tegra_dc *dc, >> return 0; >> } >> >> +static void tegra_dc_update_voltage_state(struct tegra_dc *dc, >> + struct tegra_dc_state *state) >> +{ >> + unsigned long rate, pstate; >> + struct dev_pm_opp *opp; >> + int err; >> + >> + if (!dc->has_opp_table) >> + return; >> + >> + /* calculate actual pixel clock rate which depends on internal divider */ >> + rate = DIV_ROUND_UP(clk_get_rate(dc->clk) * 2, state->div + 2); >> + >> + /* find suitable OPP for the rate */ >> + opp = dev_pm_opp_find_freq_ceil(dc->dev, &rate); >> + >> + if (opp == ERR_PTR(-ERANGE)) >> + opp = dev_pm_opp_find_freq_floor(dc->dev, &rate); >> + >> + if (IS_ERR(opp)) { >> + dev_err(dc->dev, "failed to find OPP for %luHz: %pe\n", >> + rate, opp); >> + return; >> + } >> + >> + pstate = dev_pm_opp_get_required_pstate(opp, 0); >> + dev_pm_opp_put(opp); >> + >> + /* >> + * The minimum core voltage depends on the pixel clock rate (which >> + * depends on internal clock divider of the CRTC) and not on the >> + * rate of the display controller clock. This is why we're not using >> + * dev_pm_opp_set_rate() API and instead controlling the power domain >> + * directly. >> + */ >> + err = dev_pm_genpd_set_performance_state(dc->dev, pstate); >> + if (err) >> + dev_err(dc->dev, "failed to set power domain state to %lu: %d\n", >> + pstate, err); > > Yeah, the above code looks very similar to the code I pointed to in > patch6. Perhaps we need to discuss with Viresh, whether it makes sense > to fold in a patch adding an opp helper function after all, to avoid > the open coding. > > Viresh? I'll keep it open-coded for now. This code is specific to Tegra because normally ceil error shouldn't fall back to the floor, but for Tegra it's expected to happen and it's a normal condition.
diff --git a/drivers/gpu/drm/tegra/dc.c b/drivers/gpu/drm/tegra/dc.c index a29d64f87563..d4047a14e2b6 100644 --- a/drivers/gpu/drm/tegra/dc.c +++ b/drivers/gpu/drm/tegra/dc.c @@ -11,9 +11,12 @@ #include <linux/interconnect.h> #include <linux/module.h> #include <linux/of_device.h> +#include <linux/pm_domain.h> +#include <linux/pm_opp.h> #include <linux/pm_runtime.h> #include <linux/reset.h> +#include <soc/tegra/common.h> #include <soc/tegra/pmc.h> #include <drm/drm_atomic.h> @@ -1762,6 +1765,47 @@ int tegra_dc_state_setup_clock(struct tegra_dc *dc, return 0; } +static void tegra_dc_update_voltage_state(struct tegra_dc *dc, + struct tegra_dc_state *state) +{ + unsigned long rate, pstate; + struct dev_pm_opp *opp; + int err; + + if (!dc->has_opp_table) + return; + + /* calculate actual pixel clock rate which depends on internal divider */ + rate = DIV_ROUND_UP(clk_get_rate(dc->clk) * 2, state->div + 2); + + /* find suitable OPP for the rate */ + opp = dev_pm_opp_find_freq_ceil(dc->dev, &rate); + + if (opp == ERR_PTR(-ERANGE)) + opp = dev_pm_opp_find_freq_floor(dc->dev, &rate); + + if (IS_ERR(opp)) { + dev_err(dc->dev, "failed to find OPP for %luHz: %pe\n", + rate, opp); + return; + } + + pstate = dev_pm_opp_get_required_pstate(opp, 0); + dev_pm_opp_put(opp); + + /* + * The minimum core voltage depends on the pixel clock rate (which + * depends on internal clock divider of the CRTC) and not on the + * rate of the display controller clock. This is why we're not using + * dev_pm_opp_set_rate() API and instead controlling the power domain + * directly. + */ + err = dev_pm_genpd_set_performance_state(dc->dev, pstate); + if (err) + dev_err(dc->dev, "failed to set power domain state to %lu: %d\n", + pstate, err); +} + static void tegra_dc_commit_state(struct tegra_dc *dc, struct tegra_dc_state *state) { @@ -1801,6 +1845,8 @@ static void tegra_dc_commit_state(struct tegra_dc *dc, value = SHIFT_CLK_DIVIDER(state->div) | PIXEL_CLK_DIVIDER_PCD1; tegra_dc_writel(dc, value, DC_DISP_DISP_CLOCK_CONTROL); } + + tegra_dc_update_voltage_state(dc, state); } static void tegra_dc_stop(struct tegra_dc *dc) @@ -1991,6 +2037,13 @@ static void tegra_crtc_atomic_disable(struct drm_crtc *crtc, err = host1x_client_suspend(&dc->client); if (err < 0) dev_err(dc->dev, "failed to suspend: %d\n", err); + + if (dc->has_opp_table) { + err = dev_pm_genpd_set_performance_state(dc->dev, 0); + if (err) + dev_err(dc->dev, + "failed to clear power domain state: %d\n", err); + } } static void tegra_crtc_atomic_enable(struct drm_crtc *crtc, @@ -2973,6 +3026,23 @@ static int tegra_dc_couple(struct tegra_dc *dc) return 0; } +static int tegra_dc_init_opp_table(struct tegra_dc *dc) +{ + struct tegra_core_opp_params opp_params = {}; + int err; + + err = devm_tegra_core_dev_init_opp_table(dc->dev, &opp_params); + if (err && err != -ENODEV) + return err; + + if (err) + dc->has_opp_table = false; + else + dc->has_opp_table = true; + + return 0; +} + static int tegra_dc_probe(struct platform_device *pdev) { u64 dma_mask = dma_get_mask(pdev->dev.parent); @@ -3038,6 +3108,10 @@ static int tegra_dc_probe(struct platform_device *pdev) tegra_powergate_power_off(dc->powergate); } + err = tegra_dc_init_opp_table(dc); + if (err < 0) + return err; + dc->regs = devm_platform_ioremap_resource(pdev, 0); if (IS_ERR(dc->regs)) return PTR_ERR(dc->regs); diff --git a/drivers/gpu/drm/tegra/dc.h b/drivers/gpu/drm/tegra/dc.h index 40378308d527..871cfb0cd31c 100644 --- a/drivers/gpu/drm/tegra/dc.h +++ b/drivers/gpu/drm/tegra/dc.h @@ -100,6 +100,8 @@ struct tegra_dc { struct drm_info_list *debugfs_files; const struct tegra_dc_soc_info *soc; + + bool has_opp_table; }; static inline struct tegra_dc *