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authorVille Syrjälä <ville.syrjala@linux.intel.com>2016-04-26 19:46:32 +0300
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2016-07-27 09:47:35 -0700
commit86383e482504c16fd2ad91a7ba4dcb250d4bdd51 (patch)
tree46fb627e5fb91e81407119da3aca164c5d97220e /drivers
parentedc185a40251e4727ba729ccb478d39cf76bfc54 (diff)
drm/i915: Update CDCLK_FREQ register on BDW after changing cdclk frequency
commit a04e23d42a1ce5d5f421692bb1c7e9352832819d upstream. Update CDCLK_FREQ on BDW after changing the cdclk frequency. Not sure if this is a late addition to the spec, or if I simply overlooked this step when writing the original code. This is what Bspec has to say about CDCLK_FREQ: "Program this field to the CD clock frequency minus one. This is used to generate a divided down clock for miscellaneous timers in display." And the "Broadwell Sequences for Changing CD Clock Frequency" section clarifies this further: "For CD clock 337.5 MHz, program 337 decimal. For CD clock 450 MHz, program 449 decimal. For CD clock 540 MHz, program 539 decimal. For CD clock 675 MHz, program 674 decimal." Cc: stable@vger.kernel.org Cc: Mika Kahola <mika.kahola@intel.com> Fixes: b432e5cfd5e9 ("drm/i915: BDW clock change support") Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Link: http://patchwork.freedesktop.org/patch/msgid/1461689194-6079-2-git-send-email-ville.syrjala@linux.intel.com Reviewed-by: Mika Kahola <mika.kahola@intel.com> (cherry picked from commit 7f1052a8fa38df635ab0dc0e6025b64ab9834824) Signed-off-by: Jani Nikula <jani.nikula@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers')
-rw-r--r--drivers/gpu/drm/i915/i915_reg.h2
-rw-r--r--drivers/gpu/drm/i915/intel_display.c2
2 files changed, 4 insertions, 0 deletions
diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index 7e461dca564c..9ed9f6dde86f 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -7357,6 +7357,8 @@ enum skl_disp_power_wells {
#define TRANS_CLK_SEL_DISABLED (0x0<<29)
#define TRANS_CLK_SEL_PORT(x) (((x)+1)<<29)
+#define CDCLK_FREQ 0x46200
+
#define TRANSA_MSA_MISC 0x60410
#define TRANSB_MSA_MISC 0x61410
#define TRANSC_MSA_MISC 0x62410
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 0f075fb3d9cb..c41bc42b6fa7 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -9689,6 +9689,8 @@ static void broadwell_set_cdclk(struct drm_device *dev, int cdclk)
sandybridge_pcode_write(dev_priv, HSW_PCODE_DE_WRITE_FREQ_REQ, data);
mutex_unlock(&dev_priv->rps.hw_lock);
+ I915_WRITE(CDCLK_FREQ, DIV_ROUND_CLOSEST(cdclk, 1000) - 1);
+
intel_update_cdclk(dev);
WARN(cdclk != dev_priv->cdclk_freq,