[Intel-gfx] [PATCH v6 7/8] drm/i915: BDW clock change support
Mika Kahola
mika.kahola at intel.com
Mon Jun 29 04:36:51 PDT 2015
On Mon, 2015-06-29 at 14:24 +0300, Jani Nikula wrote:
> On Tue, 16 Jun 2015, Jani Nikula <jani.nikula at linux.intel.com> wrote:
> > On Tue, 16 Jun 2015, Jani Nikula <jani.nikula at linux.intel.com> wrote:
> >> On Wed, 03 Jun 2015, Mika Kahola <mika.kahola at intel.com> wrote:
> >>> From: Ville Syrjälä <ville.syrjala at linux.intel.com>
> >>>
> >>> Add support for changing cdclk frequency during runtime on BDW. The
> >>> procedure is quite a bit different on BDW from the one on HSW, so
> >>> add a separate function for it.
> >>>
> >>> Also with IPS enabled the actual pixel rate mustn't exceed 95% of cdclk,
> >>> so take that into account when computing the max pixel rate.
> >>>
> >>> v2: Grab rps.hw_lock around sandybridge_pcode_write()
> >>> v3: Rebase due to power well vs. .global_resources() reordering
> >>> v4: Rebased to the latest
> >>> v5: Rebased to the latest
> >>> v6: Patch order shuffle so that Broadwell CD clock change is
> >>> applied before the patch for Haswell CD clock change
> >>> v7: Fix for patch style problems
> >>>
> >>> Signed-off-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
> >>> Signed-off-by: Mika Kahola <mika.kahola at intel.com>
> >>
> >> This patch hard hangs my BDW NUC at boot when both DP and HDMI are
> >> connected. Either DP or HDMI alone are good, same with hotplugging the
> >> other afterwards. Booting to grub with both connected, and unplugging
> >> HDMI before loading the kernel also reproduces the issue.
> >>
> >> It looks like the problem boils down to the BIOS setting up a smaller
> >> resolution on the DP display when both are connected, and this patch
> >> fails to cope with that on i915 load.
> >
> > By "this patch" I obviously refer to
> >
> > commit b432e5cfd5e92127ad2dd83bfc3083f1dbce43fb
> > Author: Ville Syrjälä <ville.syrjala at linux.intel.com>
> > Date: Wed Jun 3 15:45:13 2015 +0300
> >
> > drm/i915: BDW clock change support
> >
> > and everything works for the commit before that.
>
> Anyone working on this, or should we revert?
>
> BR,
> Jani.
>
My understanding is that Ville has an idea or how to fix this.
Cheers,
Mika
>
> >
> > BR,
> > Jani.
> >
> >
> >
> >
> >
> >>
> >> BR,
> >> Jani.
> >>
> >>
> >>
> >>>
> >>> Author: Ville Syrjälä <ville.syrjala at linux.intel.com>
> >>> ---
> >>> drivers/gpu/drm/i915/i915_reg.h | 2 +
> >>> drivers/gpu/drm/i915/intel_display.c | 216 +++++++++++++++++++++++++++++++++--
> >>> 2 files changed, 208 insertions(+), 10 deletions(-)
> >>>
> >>> diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
> >>> index 7213224..0f72c0e 100644
> >>> --- a/drivers/gpu/drm/i915/i915_reg.h
> >>> +++ b/drivers/gpu/drm/i915/i915_reg.h
> >>> @@ -6705,6 +6705,7 @@ enum skl_disp_power_wells {
> >>> #define GEN6_PCODE_READ_RC6VIDS 0x5
> >>> #define GEN6_ENCODE_RC6_VID(mv) (((mv) - 245) / 5)
> >>> #define GEN6_DECODE_RC6_VID(vids) (((vids) * 5) + 245)
> >>> +#define BDW_PCODE_DISPLAY_FREQ_CHANGE_REQ 0x18
> >>> #define GEN9_PCODE_READ_MEM_LATENCY 0x6
> >>> #define GEN9_MEM_LATENCY_LEVEL_MASK 0xFF
> >>> #define GEN9_MEM_LATENCY_LEVEL_1_5_SHIFT 8
> >>> @@ -7170,6 +7171,7 @@ enum skl_disp_power_wells {
> >>> #define LCPLL_CLK_FREQ_337_5_BDW (2<<26)
> >>> #define LCPLL_CLK_FREQ_675_BDW (3<<26)
> >>> #define LCPLL_CD_CLOCK_DISABLE (1<<25)
> >>> +#define LCPLL_ROOT_CD_CLOCK_DISABLE (1<<24)
> >>> #define LCPLL_CD2X_CLOCK_DISABLE (1<<23)
> >>> #define LCPLL_POWER_DOWN_ALLOW (1<<22)
> >>> #define LCPLL_CD_SOURCE_FCLK (1<<21)
> >>> diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
> >>> index c3f01aa..b1e2069 100644
> >>> --- a/drivers/gpu/drm/i915/intel_display.c
> >>> +++ b/drivers/gpu/drm/i915/intel_display.c
> >>> @@ -5751,7 +5751,22 @@ static void intel_update_max_cdclk(struct drm_device *dev)
> >>> {
> >>> struct drm_i915_private *dev_priv = dev->dev_private;
> >>>
> >>> - if (IS_VALLEYVIEW(dev)) {
> >>> + if (IS_BROADWELL(dev)) {
> >>> + /*
> >>> + * FIXME with extra cooling we can allow
> >>> + * 540 MHz for ULX and 675 Mhz for ULT.
> >>> + * How can we know if extra cooling is
> >>> + * available? PCI ID, VTB, something else?
> >>> + */
> >>> + if (I915_READ(FUSE_STRAP) & HSW_CDCLK_LIMIT)
> >>> + dev_priv->max_cdclk_freq = 450000;
> >>> + else if (IS_BDW_ULX(dev))
> >>> + dev_priv->max_cdclk_freq = 450000;
> >>> + else if (IS_BDW_ULT(dev))
> >>> + dev_priv->max_cdclk_freq = 540000;
> >>> + else
> >>> + dev_priv->max_cdclk_freq = 675000;
> >>> + } else if (IS_VALLEYVIEW(dev)) {
> >>> dev_priv->max_cdclk_freq = 400000;
> >>> } else {
> >>> /* otherwise assume cdclk is fixed */
> >>> @@ -6621,13 +6636,11 @@ static bool pipe_config_supports_ips(struct drm_i915_private *dev_priv,
> >>> return true;
> >>>
> >>> /*
> >>> - * FIXME if we compare against max we should then
> >>> - * increase the cdclk frequency when the current
> >>> - * value is too low. The other option is to compare
> >>> - * against the cdclk frequency we're going have post
> >>> - * modeset (ie. one we computed using other constraints).
> >>> - * Need to measure whether using a lower cdclk w/o IPS
> >>> - * is better or worse than a higher cdclk w/ IPS.
> >>> + * We compare against max which means we must take
> >>> + * the increased cdclk requirement into account when
> >>> + * calculating the new cdclk.
> >>> + *
> >>> + * Should measure whether using a lower cdclk w/o IPS
> >>> */
> >>> return ilk_pipe_pixel_rate(pipe_config) <=
> >>> dev_priv->max_cdclk_freq * 95 / 100;
> >>> @@ -9608,6 +9621,182 @@ static void broxton_modeset_global_resources(struct drm_atomic_state *old_state)
> >>> broxton_set_cdclk(dev, req_cdclk);
> >>> }
> >>>
> >>> +/* compute the max rate for new configuration */
> >>> +static int ilk_max_pixel_rate(struct drm_i915_private *dev_priv)
> >>> +{
> >>> + struct drm_device *dev = dev_priv->dev;
> >>> + struct intel_crtc *intel_crtc;
> >>> + struct drm_crtc *crtc;
> >>> + int max_pixel_rate = 0;
> >>> + int pixel_rate;
> >>> +
> >>> + for_each_crtc(dev, crtc) {
> >>> + if (!crtc->state->enable)
> >>> + continue;
> >>> +
> >>> + intel_crtc = to_intel_crtc(crtc);
> >>> + pixel_rate = ilk_pipe_pixel_rate(intel_crtc->config);
> >>> +
> >>> + /* pixel rate mustn't exceed 95% of cdclk with IPS on BDW */
> >>> + if (IS_BROADWELL(dev) && intel_crtc->config->ips_enabled)
> >>> + pixel_rate = DIV_ROUND_UP(pixel_rate * 100, 95);
> >>> +
> >>> + max_pixel_rate = max(max_pixel_rate, pixel_rate);
> >>> + }
> >>> +
> >>> + return max_pixel_rate;
> >>> +}
> >>> +
> >>> +static void broadwell_set_cdclk(struct drm_device *dev, int cdclk)
> >>> +{
> >>> + struct drm_i915_private *dev_priv = dev->dev_private;
> >>> + uint32_t val, data;
> >>> + int ret;
> >>> +
> >>> + if (WARN((I915_READ(LCPLL_CTL) &
> >>> + (LCPLL_PLL_DISABLE | LCPLL_PLL_LOCK |
> >>> + LCPLL_CD_CLOCK_DISABLE | LCPLL_ROOT_CD_CLOCK_DISABLE |
> >>> + LCPLL_CD2X_CLOCK_DISABLE | LCPLL_POWER_DOWN_ALLOW |
> >>> + LCPLL_CD_SOURCE_FCLK)) != LCPLL_PLL_LOCK,
> >>> + "trying to change cdclk frequency with cdclk not enabled\n"))
> >>> + return;
> >>> +
> >>> + mutex_lock(&dev_priv->rps.hw_lock);
> >>> + ret = sandybridge_pcode_write(dev_priv,
> >>> + BDW_PCODE_DISPLAY_FREQ_CHANGE_REQ, 0x0);
> >>> + mutex_unlock(&dev_priv->rps.hw_lock);
> >>> + if (ret) {
> >>> + DRM_ERROR("failed to inform pcode about cdclk change\n");
> >>> + return;
> >>> + }
> >>> +
> >>> + val = I915_READ(LCPLL_CTL);
> >>> + val |= LCPLL_CD_SOURCE_FCLK;
> >>> + I915_WRITE(LCPLL_CTL, val);
> >>> +
> >>> + if (wait_for_atomic_us(I915_READ(LCPLL_CTL) &
> >>> + LCPLL_CD_SOURCE_FCLK_DONE, 1))
> >>> + DRM_ERROR("Switching to FCLK failed\n");
> >>> +
> >>> + val = I915_READ(LCPLL_CTL);
> >>> + val &= ~LCPLL_CLK_FREQ_MASK;
> >>> +
> >>> + switch (cdclk) {
> >>> + case 450000:
> >>> + val |= LCPLL_CLK_FREQ_450;
> >>> + data = 0;
> >>> + break;
> >>> + case 540000:
> >>> + val |= LCPLL_CLK_FREQ_54O_BDW;
> >>> + data = 1;
> >>> + break;
> >>> + case 337500:
> >>> + val |= LCPLL_CLK_FREQ_337_5_BDW;
> >>> + data = 2;
> >>> + break;
> >>> + case 675000:
> >>> + val |= LCPLL_CLK_FREQ_675_BDW;
> >>> + data = 3;
> >>> + break;
> >>> + default:
> >>> + WARN(1, "invalid cdclk frequency\n");
> >>> + return;
> >>> + }
> >>> +
> >>> + I915_WRITE(LCPLL_CTL, val);
> >>> +
> >>> + val = I915_READ(LCPLL_CTL);
> >>> + val &= ~LCPLL_CD_SOURCE_FCLK;
> >>> + I915_WRITE(LCPLL_CTL, val);
> >>> +
> >>> + if (wait_for_atomic_us((I915_READ(LCPLL_CTL) &
> >>> + LCPLL_CD_SOURCE_FCLK_DONE) == 0, 1))
> >>> + DRM_ERROR("Switching back to LCPLL failed\n");
> >>> +
> >>> + mutex_lock(&dev_priv->rps.hw_lock);
> >>> + sandybridge_pcode_write(dev_priv, HSW_PCODE_DE_WRITE_FREQ_REQ, data);
> >>> + mutex_unlock(&dev_priv->rps.hw_lock);
> >>> +
> >>> + intel_update_cdclk(dev);
> >>> +
> >>> + WARN(cdclk != dev_priv->cdclk_freq,
> >>> + "cdclk requested %d kHz but got %d kHz\n",
> >>> + cdclk, dev_priv->cdclk_freq);
> >>> +}
> >>> +
> >>> +static int broadwell_calc_cdclk(struct drm_i915_private *dev_priv,
> >>> + int max_pixel_rate)
> >>> +{
> >>> + int cdclk;
> >>> +
> >>> + /*
> >>> + * FIXME should also account for plane ratio
> >>> + * once 64bpp pixel formats are supported.
> >>> + */
> >>> + if (max_pixel_rate > 540000)
> >>> + cdclk = 675000;
> >>> + else if (max_pixel_rate > 450000)
> >>> + cdclk = 540000;
> >>> + else if (max_pixel_rate > 337500)
> >>> + cdclk = 450000;
> >>> + else
> >>> + cdclk = 337500;
> >>> +
> >>> + /*
> >>> + * FIXME move the cdclk caclulation to
> >>> + * compute_config() so we can fail gracegully.
> >>> + */
> >>> + if (cdclk > dev_priv->max_cdclk_freq) {
> >>> + DRM_ERROR("requested cdclk (%d kHz) exceeds max (%d kHz)\n",
> >>> + cdclk, dev_priv->max_cdclk_freq);
> >>> + cdclk = dev_priv->max_cdclk_freq;
> >>> + }
> >>> +
> >>> + return cdclk;
> >>> +}
> >>> +
> >>> +static int broadwell_modeset_global_pipes(struct drm_atomic_state *state)
> >>> +{
> >>> + struct drm_i915_private *dev_priv = to_i915(state->dev);
> >>> + struct drm_crtc *crtc;
> >>> + struct drm_crtc_state *crtc_state;
> >>> + int max_pixclk = ilk_max_pixel_rate(dev_priv);
> >>> + int cdclk, i;
> >>> +
> >>> + cdclk = broadwell_calc_cdclk(dev_priv, max_pixclk);
> >>> +
> >>> + if (cdclk == dev_priv->cdclk_freq)
> >>> + return 0;
> >>> +
> >>> + /* add all active pipes to the state */
> >>> + for_each_crtc(state->dev, crtc) {
> >>> + if (!crtc->state->enable)
> >>> + continue;
> >>> +
> >>> + crtc_state = drm_atomic_get_crtc_state(state, crtc);
> >>> + if (IS_ERR(crtc_state))
> >>> + return PTR_ERR(crtc_state);
> >>> + }
> >>> +
> >>> + /* disable/enable all currently active pipes while we change cdclk */
> >>> + for_each_crtc_in_state(state, crtc, crtc_state, i)
> >>> + if (crtc_state->enable)
> >>> + crtc_state->mode_changed = true;
> >>> +
> >>> + return 0;
> >>> +}
> >>> +
> >>> +static void broadwell_modeset_global_resources(struct drm_atomic_state *state)
> >>> +{
> >>> + struct drm_device *dev = state->dev;
> >>> + struct drm_i915_private *dev_priv = dev->dev_private;
> >>> + int max_pixel_rate = ilk_max_pixel_rate(dev_priv);
> >>> + int req_cdclk = broadwell_calc_cdclk(dev_priv, max_pixel_rate);
> >>> +
> >>> + if (req_cdclk != dev_priv->cdclk_freq)
> >>> + broadwell_set_cdclk(dev, req_cdclk);
> >>> +}
> >>> +
> >>> static int haswell_crtc_compute_clock(struct intel_crtc *crtc,
> >>> struct intel_crtc_state *crtc_state)
> >>> {
> >>> @@ -12788,8 +12977,12 @@ static int __intel_set_mode_checks(struct drm_atomic_state *state)
> >>> * mode set on this crtc. For other crtcs we need to use the
> >>> * adjusted_mode bits in the crtc directly.
> >>> */
> >>> - if (IS_VALLEYVIEW(dev) || IS_BROXTON(dev)) {
> >>> - ret = valleyview_modeset_global_pipes(state);
> >>> + if (IS_VALLEYVIEW(dev) || IS_BROXTON(dev) || IS_BROADWELL(dev)) {
> >>> + if (IS_VALLEYVIEW(dev) || IS_BROXTON(dev))
> >>> + ret = valleyview_modeset_global_pipes(state);
> >>> + else
> >>> + ret = broadwell_modeset_global_pipes(state);
> >>> +
> >>> if (ret)
> >>> return ret;
> >>> }
> >>> @@ -14677,6 +14870,9 @@ static void intel_init_display(struct drm_device *dev)
> >>> dev_priv->display.fdi_link_train = ivb_manual_fdi_link_train;
> >>> } else if (IS_HASWELL(dev) || IS_BROADWELL(dev)) {
> >>> dev_priv->display.fdi_link_train = hsw_fdi_link_train;
> >>> + if (IS_BROADWELL(dev))
> >>> + dev_priv->display.modeset_global_resources =
> >>> + broadwell_modeset_global_resources;
> >>> } else if (IS_VALLEYVIEW(dev)) {
> >>> dev_priv->display.modeset_global_resources =
> >>> valleyview_modeset_global_resources;
> >>> --
> >>> 1.9.1
> >>>
> >>> _______________________________________________
> >>> Intel-gfx mailing list
> >>> Intel-gfx at lists.freedesktop.org
> >>> http://lists.freedesktop.org/mailman/listinfo/intel-gfx
> >>
> >> --
> >> Jani Nikula, Intel Open Source Technology Center
> >
> > --
> > Jani Nikula, Intel Open Source Technology Center
>
> --
> Jani Nikula, Intel Open Source Technology Center
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