drm/i915: Clarify VLV PLL p1 limits

For some reason there's a sort of off by one issue with the p1 divider.
The actual p1 limits according to
VLV2_DPLL_mphy_hsdpll_frequency_table_ww6_rev1p1.xlsm is 2-3, so we should
just say that instead of saying 1-3 and avoiding the 1 via the choice of
comparison operator.

I don't know why we're using different p1 limits for intel_limits_vlv_dac
and intel_limits_vlv_hdmi, but let's preserve that for now.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
This commit is contained in:
Ville Syrjälä 2013-09-24 21:26:25 +03:00 committed by Daniel Vetter
parent 27e639bf02
commit 811bbf0544
1 changed files with 3 additions and 3 deletions

View File

@ -317,7 +317,7 @@ static const intel_limit_t intel_limits_vlv_dac = {
.m1 = { .min = 2, .max = 3 },
.m2 = { .min = 11, .max = 156 },
.p = { .min = 10, .max = 30 },
.p1 = { .min = 1, .max = 3 },
.p1 = { .min = 2, .max = 3 },
.p2 = { .dot_limit = 270000,
.p2_slow = 2, .p2_fast = 20 },
};
@ -330,7 +330,7 @@ static const intel_limit_t intel_limits_vlv_hdmi = {
.m1 = { .min = 2, .max = 3 },
.m2 = { .min = 11, .max = 156 },
.p = { .min = 10, .max = 30 },
.p1 = { .min = 2, .max = 3 },
.p1 = { .min = 3, .max = 3 },
.p2 = { .dot_limit = 270000,
.p2_slow = 2, .p2_fast = 20 },
};
@ -688,7 +688,7 @@ vlv_find_best_dpll(const intel_limit_t *limit, struct drm_crtc *crtc,
/* based on hardware requirement, prefer smaller n to precision */
for (clock.n = limit->n.min; clock.n <= max_n; clock.n++) {
for (clock.p1 = limit->p1.max; clock.p1 > limit->p1.min; clock.p1--) {
for (clock.p1 = limit->p1.max; clock.p1 >= limit->p1.min; clock.p1--) {
for (clock.p2 = limit->p2.p2_fast; clock.p2 > 0;
clock.p2 -= clock.p2 > 10 ? 2 : 1) {
clock.p = clock.p1 * clock.p2;