[Intel-gfx] [PATCH v6 7/8] drm/i915: BDW clock change support
Jani Nikula
jani.nikula at linux.intel.com
Mon Jun 29 04:24:54 PDT 2015
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.
>
> 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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