Re: [PATCH v3 13/13] drm/i915: Make SKL/KBL DPLL0 managed by the shared dpll code

Maarten Lankhorst
2016-03-03T13:34:01Z

Op 29-02-16 om 10:08 schreef Ander Conselvan de Oliveira:
> Include DPLL0 in the managed dplls for SKL/KBL. While it has to be kept
> enabled because of it driving CDCLK, it is better to special case that
> inside the DPLL code than in the higher level.
>
> v2: Use INTEL_DPLL_ALWAYS_ON flag. (Ander)
>
> Signed-off-by: Ander Conselvan de Oliveira <ander.conselvan.de.oliveira@intel.com>
>
> ---
> I wasn't able to test this patch. Would really appreciate a tested by
> from someone.
Unfortunately no skl with eDP here either. :(
> drivers/gpu/drm/i915/intel_ddi.c | 21 ------
> drivers/gpu/drm/i915/intel_dp.c | 52 +-------------
> drivers/gpu/drm/i915/intel_dpll_mgr.c | 131 +++++++++++++++++++++++++++-------
> drivers/gpu/drm/i915/intel_dpll_mgr.h | 7 +-
> 4 files changed, 109 insertions(+), 102 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/intel_ddi.c b/drivers/gpu/drm/i915/intel_ddi.c
> index 3cb9f36..8ef4d2e 100644
> --- a/drivers/gpu/drm/i915/intel_ddi.c
> +++ b/drivers/gpu/drm/i915/intel_ddi.c
> @@ -1008,9 +1008,6 @@ skl_ddi_pll_select(struct intel_crtc *intel_crtc,
> {
> struct intel_shared_dpll *pll;
>
> - if (intel_encoder->type == INTEL_OUTPUT_EDP)
> - return true;
> -
> pll = intel_get_shared_dpll(intel_crtc, crtc_state, intel_encoder);
> if (pll == NULL) {
> DRM_DEBUG_DRIVER("failed to find PLL for pipe %c\n",
> @@ -1570,24 +1567,6 @@ void intel_ddi_clk_select(struct intel_encoder *encoder,
> uint32_t dpll = pipe_config->ddi_pll_sel;
> uint32_t val;
>
> - /*
> - * DPLL0 is used for eDP and is the only "private" DPLL (as
> - * opposed to shared) on SKL
> - */
> - if (encoder->type == INTEL_OUTPUT_EDP) {
> - WARN_ON(dpll != SKL_DPLL0);
> -
> - val = I915_READ(DPLL_CTRL1);
> -
> - val &= ~(DPLL_CTRL1_HDMI_MODE(dpll) |
> - DPLL_CTRL1_SSC(dpll) |
> - DPLL_CTRL1_LINK_RATE_MASK(dpll));
> - val |= pipe_config->dpll_hw_state.ctrl1 << (dpll * 6);
> -
> - I915_WRITE(DPLL_CTRL1, val);
> - POSTING_READ(DPLL_CTRL1);
> - }
> -
> /* DDI -> PLL mapping */
> val = I915_READ(DPLL_CTRL2);
>
> diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
> index 5be6892..9fef877 100644
> --- a/drivers/gpu/drm/i915/intel_dp.c
> +++ b/drivers/gpu/drm/i915/intel_dp.c
> @@ -1229,52 +1229,6 @@ intel_dp_connector_unregister(struct intel_connector *intel_connector)
> intel_connector_unregister(intel_connector);
> }
>
> -static void
> -skl_edp_set_pll_config(struct intel_crtc_state *pipe_config)
> -{
> - u32 ctrl1;
> -
> - memset(&pipe_config->dpll_hw_state, 0,
> - sizeof(pipe_config->dpll_hw_state));
> -
> - pipe_config->ddi_pll_sel = SKL_DPLL0;
> - pipe_config->dpll_hw_state.cfgcr1 = 0;
> - pipe_config->dpll_hw_state.cfgcr2 = 0;
> -
> - ctrl1 = DPLL_CTRL1_OVERRIDE(SKL_DPLL0);
> - switch (pipe_config->port_clock / 2) {
> - case 81000:
> - ctrl1 |= DPLL_CTRL1_LINK_RATE(DPLL_CTRL1_LINK_RATE_810,
> - SKL_DPLL0);
> - break;
> - case 135000:
> - ctrl1 |= DPLL_CTRL1_LINK_RATE(DPLL_CTRL1_LINK_RATE_1350,
> - SKL_DPLL0);
> - break;
> - case 270000:
> - ctrl1 |= DPLL_CTRL1_LINK_RATE(DPLL_CTRL1_LINK_RATE_2700,
> - SKL_DPLL0);
> - break;
> - case 162000:
> - ctrl1 |= DPLL_CTRL1_LINK_RATE(DPLL_CTRL1_LINK_RATE_1620,
> - SKL_DPLL0);
> - break;
> - /* TBD: For DP link rates 2.16 GHz and 4.32 GHz, VCO is 8640 which
> - results in CDCLK change. Need to handle the change of CDCLK by
> - disabling pipes and re-enabling them */
> - case 108000:
> - ctrl1 |= DPLL_CTRL1_LINK_RATE(DPLL_CTRL1_LINK_RATE_1080,
> - SKL_DPLL0);
> - break;
> - case 216000:
> - ctrl1 |= DPLL_CTRL1_LINK_RATE(DPLL_CTRL1_LINK_RATE_2160,
> - SKL_DPLL0);
> - break;
> -
> - }
> - pipe_config->dpll_hw_state.ctrl1 = ctrl1;
> -}
> -
> static int
> intel_dp_sink_rates(struct intel_dp *intel_dp, const int **sink_rates)
> {
> @@ -1632,11 +1586,7 @@ found:
> &pipe_config->dp_m2_n2);
> }
>
> - if ((IS_SKYLAKE(dev) || IS_KABYLAKE(dev)) && is_edp(intel_dp))
> - skl_edp_set_pll_config(pipe_config);
> - else if (IS_BROXTON(dev) || IS_HASWELL(dev) || IS_BROADWELL(dev))
> - /* handled in ddi */;
> - else
> + if (!HAS_DDI(dev))
> intel_dp_set_clock(encoder, pipe_config);
>
> return true;
> diff --git a/drivers/gpu/drm/i915/intel_dpll_mgr.c b/drivers/gpu/drm/i915/intel_dpll_mgr.c
> index d371680..6ec7836 100644
> --- a/drivers/gpu/drm/i915/intel_dpll_mgr.c
> +++ b/drivers/gpu/drm/i915/intel_dpll_mgr.c
> @@ -785,7 +785,12 @@ struct skl_dpll_regs {
> };
>
> /* this array is indexed by the *shared* pll id */
> -static const struct skl_dpll_regs skl_dpll_regs[3] = {
> +static const struct skl_dpll_regs skl_dpll_regs[4] = {
> + {
> + /* DPLL 0 */
> + .ctl = LCPLL1_CTL,
> + /* DPLL 0 doesn't support HDMI mode */
> + },
> {
> /* DPLL 1 */
> .ctl = LCPLL2_CTL,
> @@ -806,24 +811,29 @@ static const struct skl_dpll_regs skl_dpll_regs[3] = {
> },
> };
>
> -static void skl_ddi_pll_enable(struct drm_i915_private *dev_priv,
> - struct intel_shared_dpll *pll)
> +static void skl_ddi_pll_write_ctrl1(struct drm_i915_private *dev_priv,
> + struct intel_shared_dpll *pll)
> {
> uint32_t val;
> - unsigned int dpll;
> - const struct skl_dpll_regs *regs = skl_dpll_regs;
> -
> - /* DPLL0 is not part of the shared DPLLs, so pll->id is 0 for DPLL1 */
> - dpll = pll->id + 1;
>
> val = I915_READ(DPLL_CTRL1);
>
> - val &= ~(DPLL_CTRL1_HDMI_MODE(dpll) | DPLL_CTRL1_SSC(dpll) |
> - DPLL_CTRL1_LINK_RATE_MASK(dpll));
> - val |= pll->config.hw_state.ctrl1 << (dpll * 6);
> + val &= ~(DPLL_CTRL1_HDMI_MODE(pll->id) | DPLL_CTRL1_SSC(pll->id) |
> + DPLL_CTRL1_LINK_RATE_MASK(pll->id));
> + val |= pll->config.hw_state.ctrl1 << (pll->id * 6);
>
> I915_WRITE(DPLL_CTRL1, val);
> POSTING_READ(DPLL_CTRL1);
> +}
> +
> +static void skl_ddi_pll_enable(struct drm_i915_private *dev_priv,
> + struct intel_shared_dpll *pll)
> +{
> + const struct skl_dpll_regs *regs = skl_dpll_regs;
> +
> + WARN_ON(pll->id == DPLL_ID_SKL_DPLL0);
> +
> + skl_ddi_pll_write_ctrl1(dev_priv, pll);
>
> I915_WRITE(regs[pll->id].cfgcr1, pll->config.hw_state.cfgcr1);
> I915_WRITE(regs[pll->id].cfgcr2, pll->config.hw_state.cfgcr2);
> @@ -834,8 +844,15 @@ static void skl_ddi_pll_enable(struct drm_i915_private *dev_priv,
> I915_WRITE(regs[pll->id].ctl,
> I915_READ(regs[pll->id].ctl) | LCPLL_PLL_ENABLE);
>
> - if (wait_for(I915_READ(DPLL_STATUS) & DPLL_LOCK(dpll), 5))
> - DRM_ERROR("DPLL %d not locked\n", dpll);
> + if (wait_for(I915_READ(DPLL_STATUS) & DPLL_LOCK(pll->id), 5))
> + DRM_ERROR("DPLL %d not locked\n", pll->id);
> +}
> +
> +static void skl_ddi_dpll0_enable(struct drm_i915_private *dev_priv,
> + struct intel_shared_dpll *pll)
> +{
> + WARN_ON(pll->id != DPLL_ID_SKL_DPLL0);
> + skl_ddi_pll_write_ctrl1(dev_priv, pll);
> }
>
> static void skl_ddi_pll_disable(struct drm_i915_private *dev_priv,
> @@ -849,32 +866,35 @@ static void skl_ddi_pll_disable(struct drm_i915_private *dev_priv,
> POSTING_READ(regs[pll->id].ctl);
> }
>
> +static void skl_ddi_dpll0_disable(struct drm_i915_private *dev_priv,
> + struct intel_shared_dpll *pll)
> +{
> +}
> +
> static bool skl_ddi_pll_get_hw_state(struct drm_i915_private *dev_priv,
> struct intel_shared_dpll *pll,
> struct intel_dpll_hw_state *hw_state)
> {
> uint32_t val;
> - unsigned int dpll;
> const struct skl_dpll_regs *regs = skl_dpll_regs;
> bool ret;
>
> + WARN_ON(pll->id == DPLL_ID_SKL_DPLL0);
> +
> if (!intel_display_power_get_if_enabled(dev_priv, POWER_DOMAIN_PLLS))
> return false;
>
> ret = false;
>
> - /* DPLL0 is not part of the shared DPLLs, so pll->id is 0 for DPLL1 */
> - dpll = pll->id + 1;
> -
> val = I915_READ(regs[pll->id].ctl);
> if (!(val & LCPLL_PLL_ENABLE))
> goto out;
>
> val = I915_READ(DPLL_CTRL1);
> - hw_state->ctrl1 = (val >> (dpll * 6)) & 0x3f;
> + hw_state->ctrl1 = (val >> (pll->id * 6)) & 0x3f;
>
> /* avoid reading back stale values if HDMI mode is not enabled */
> - if (val & DPLL_CTRL1_HDMI_MODE(dpll)) {
> + if (val & DPLL_CTRL1_HDMI_MODE(pll->id)) {
> hw_state->cfgcr1 = I915_READ(regs[pll->id].cfgcr1);
> hw_state->cfgcr2 = I915_READ(regs[pll->id].cfgcr2);
> }
> @@ -886,6 +906,37 @@ out:
> return ret;
> }
>
> +static bool skl_ddi_dpll0_get_hw_state(struct drm_i915_private *dev_priv,
> + struct intel_shared_dpll *pll,
> + struct intel_dpll_hw_state *hw_state)
> +{
> + uint32_t val;
> + const struct skl_dpll_regs *regs = skl_dpll_regs;
> + bool ret;
> +
> + WARN_ON(pll->id != DPLL_ID_SKL_DPLL0);
I'm all for paranoia, but how can this ever happen?

Seems pll0 has its own function pointers, so you'd have to do something like pll1->funcs->get_hw_state(pll0);

I don't think this will ever happen, so all the paranoia from these functions that are called from the function pointer can be removed.
> + if (!intel_display_power_get_if_enabled(dev_priv, POWER_DOMAIN_PLLS))
> + return false;
> +
> + ret = false;
> +
> + /* DPLL0 is always enabled since it drives CDCLK */
> + val = I915_READ(regs[pll->id].ctl);
> + if (WARN_ON(!(val & LCPLL_PLL_ENABLE)))
> + goto out;
> +
> + val = I915_READ(DPLL_CTRL1);
> + hw_state->ctrl1 = (val >> (pll->id * 6)) & 0x3f;
> +
> + ret = true;
> +
> +out:
> + intel_display_power_put(dev_priv, POWER_DOMAIN_PLLS);
> +
> + return ret;
> +}
> +
> struct skl_wrpll_context {
> uint64_t min_deviation; /* current minimal deviation */
> uint64_t central_freq; /* chosen central freq */
> @@ -1165,7 +1216,8 @@ skl_get_dpll(struct intel_crtc *crtc, struct intel_crtc_state *crtc_state,
> DPLL_CFGCR2_PDIV(wrpll_params.pdiv) |
> wrpll_params.central_freq;
> } else if (encoder->type == INTEL_OUTPUT_DISPLAYPORT ||
> - encoder->type == INTEL_OUTPUT_DP_MST) {
> + encoder->type == INTEL_OUTPUT_DP_MST ||
> + encoder->type == INTEL_OUTPUT_EDP) {
> switch (crtc_state->port_clock / 2) {
> case 81000:
> ctrl1 |= DPLL_CTRL1_LINK_RATE(DPLL_CTRL1_LINK_RATE_810, 0);
> @@ -1176,6 +1228,19 @@ skl_get_dpll(struct intel_crtc *crtc, struct intel_crtc_state *crtc_state,
> case 270000:
> ctrl1 |= DPLL_CTRL1_LINK_RATE(DPLL_CTRL1_LINK_RATE_2700, 0);
> break;
> + /* eDP 1.4 rates */
> + case 162000:
> + ctrl1 |= DPLL_CTRL1_LINK_RATE(DPLL_CTRL1_LINK_RATE_1620, 0);
> + break;
> + /* TBD: For DP link rates 2.16 GHz and 4.32 GHz, VCO is 8640 which
> + results in CDCLK change. Need to handle the change of CDCLK by
> + disabling pipes and re-enabling them */
Sounds like we really need to start supporting cdclk changes on SKL, if it's based on this pll?
modeset_calc_cdclk and modeset_commit_cdclk.

~Maarten