drm/i915: Update RAWCLK_FREQ register on VLV/CHV

I just noticed that VLV/CHV have a RAWCLK_FREQ register just like PCH
platforms. It lives in the display power well, so we should update it
when enabling the power well.

Interestingly the BIOS seems to leave it at the reset value (125) which
doesn't match the rawclk frequency on VLV/CHV (200 MHz). As always with
these register, the spec is extremely vague what the register does. All
it says is: "This is used to generate a divided down clock for
miscellaneous timers in display." Based on a quick test, at least AUX
and PWM appear to be unaffected by this.

But since the register is there, let's configure it in accordance with
the spec.

Note that we have to move intel_update_rawclk() to occur before we
touch the power wells, so that the dev_priv->rawclk_freq is already
populated when the disp2 enable hook gets called for the first time.
I think this should be safe to do on other platforms as well.

Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1461768202-17544-1-git-send-email-ville.syrjala@linux.intel.com
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
This commit is contained in:
Ville Syrjälä 2016-04-27 17:43:22 +03:00
parent d1877c0f07
commit 19ab4ed329
5 changed files with 13 additions and 2 deletions

View file

@ -454,6 +454,9 @@ static int i915_load_modeset_init(struct drm_device *dev)
if (ret)
goto cleanup_vga_client;
/* must happen before intel_power_domains_init_hw() on VLV/CHV */
intel_update_rawclk(dev_priv);
intel_power_domains_init_hw(dev_priv, false);
intel_csr_ucode_init(dev_priv);

View file

@ -2449,6 +2449,8 @@ enum skl_disp_power_wells {
#define DPLL_MD_VGA_UDI_MULTIPLIER_MASK 0x0000003f
#define DPLL_MD_VGA_UDI_MULTIPLIER_SHIFT 0
#define RAWCLK_FREQ_VLV _MMIO(VLV_DISPLAY_BASE + 0x6024)
#define _FPA0 0x6040
#define _FPA1 0x6044
#define _FPB0 0x6048

View file

@ -185,6 +185,7 @@ intel_pch_rawclk(struct drm_i915_private *dev_priv)
static int
intel_vlv_hrawclk(struct drm_i915_private *dev_priv)
{
/* RAWCLK_FREQ_VLV register updated from power well code */
return vlv_get_cck_clock_hpll(dev_priv, "hrawclk",
CCK_DISPLAY_REF_CLOCK_CONTROL);
}
@ -218,7 +219,7 @@ intel_g4x_hrawclk(struct drm_i915_private *dev_priv)
}
}
static void intel_update_rawclk(struct drm_i915_private *dev_priv)
void intel_update_rawclk(struct drm_i915_private *dev_priv)
{
if (HAS_PCH_SPLIT(dev_priv))
dev_priv->rawclk_freq = intel_pch_rawclk(dev_priv);
@ -15455,7 +15456,6 @@ void intel_modeset_init(struct drm_device *dev)
}
intel_update_czclk(dev_priv);
intel_update_rawclk(dev_priv);
intel_update_cdclk(dev);
intel_shared_dpll_init(dev);

View file

@ -1110,6 +1110,7 @@ void i915_audio_component_init(struct drm_i915_private *dev_priv);
void i915_audio_component_cleanup(struct drm_i915_private *dev_priv);
/* intel_display.c */
void intel_update_rawclk(struct drm_i915_private *dev_priv);
int vlv_get_cck_clock(struct drm_i915_private *dev_priv,
const char *name, u32 reg, int ref_freq);
extern const struct drm_plane_funcs intel_plane_funcs;

View file

@ -948,6 +948,11 @@ static void vlv_init_display_clock_gating(struct drm_i915_private *dev_priv)
*/
I915_WRITE(MI_ARB_VLV, MI_ARB_DISPLAY_TRICKLE_FEED_DISABLE);
I915_WRITE(CBR1_VLV, 0);
WARN_ON(dev_priv->rawclk_freq == 0);
I915_WRITE(RAWCLK_FREQ_VLV,
DIV_ROUND_CLOSEST(dev_priv->rawclk_freq, 1000));
}
static void vlv_display_power_well_init(struct drm_i915_private *dev_priv)