[Intel-gfx] [PATCH] drm/i915/bxt: Port PLL programming BUN
Imre Deak
imre.deak at intel.com
Tue May 5 09:49:10 PDT 2015
On ti, 2015-05-05 at 22:14 +0530, Kannan, Vandana wrote:
>
> On 5/5/2015 9:14 PM, Imre Deak wrote:
> > On ma, 2015-05-04 at 20:50 +0530, Vandana Kannan wrote:
> >> BUN 1: prop_coeff, int_coeff, tdctargetcnt programming updated and tied to
> >> VCO frequencies. Program i_lockthresh in PORT_PLL_9.
> >>
> >> VCO calculated based on the formula:
> >> Desired Output = Port bit rate in MHz (DisplayPort HBR2 is 5400 MHz)
> >> Fast Clock = Desired Output / 2
> >> VCO = Fast Clock * P1 * P2
> >>
> >> Prop_coeff, int_coeff, and tdctargetcnt modified according to above
> >> calculation.
> >>
> >> BUN 2: Port PLLs require additional programming at certain frequencies -
> >> DCO amplitude in PORT_PLL_10
> >>
> >> Review comments from Siva which were addressed in the initial version of the
> >> patch.
> >> - Change PORT_PLL_LOCK_THRESHOLD to PORT_PLL_LOCK_THRESHOLD_MASK
> >> - Calculate for HDMI
> >> - Correct values for vco = 5.4
> >> - return in case of invalid vco range
> >>
> >> Signed-off-by: Vandana Kannan <vandana.kannan at intel.com>
> >> Cc: Sivakumar Thulasimani <sivakumar.thulasimani at intel.com>
> >> ---
> >> drivers/gpu/drm/i915/i915_drv.h | 2 +-
> >> drivers/gpu/drm/i915/i915_reg.h | 6 ++++
> >> drivers/gpu/drm/i915/intel_ddi.c | 72 +++++++++++++++++++++++++++++++---------
> >> 3 files changed, 63 insertions(+), 17 deletions(-)
> >>
>
> [...]
>
> >>
> >> /* Recalibrate with new settings */
> >> temp = I915_READ(BXT_PORT_PLL_EBB_4(port));
> >> @@ -2415,6 +2454,7 @@ static bool bxt_ddi_pll_get_hw_state(struct drm_i915_private *dev_priv,
> >> hw_state->pll3 = I915_READ(BXT_PORT_PLL(port, 3));
> >> hw_state->pll6 = I915_READ(BXT_PORT_PLL(port, 6));
> >> hw_state->pll8 = I915_READ(BXT_PORT_PLL(port, 8));
> >> + hw_state->pll10 = I915_READ(BXT_PORT_PLL(port, 10));
> >> /*
> >> * While we write to the group register to program all lanes at once we
> >> * can read only lane registers. We configure all lanes the same way, so
> >
> > We should also read out pll10 in bxt_ddi_pll_get_hw_state() for
> > consistency.
> >
> I have added a readout above for pll10 or am I missing something ?
> Agree with all other comments, will resend the patch with the changes made.
Ah sorry, I was blind. Ignore my comment about it.
--Imre
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