drm/i915/skl: Factor out computing the DPLL paramaters from the dividers

This part doesn't depend on how we compute the DPLL dividers (p and
p0/p1/p2) and can be reused even if we change the algorithm to do so.
(something that is planned for a followup patch)

Signed-off-by: Damien Lespiau <damien.lespiau@intel.com>
Reviewed-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
This commit is contained in:
Damien Lespiau 2015-05-07 18:38:42 +01:00 committed by Daniel Vetter
parent 9c2367538d
commit 76516fbc29

View file

@ -1115,6 +1115,75 @@ struct skl_wrpll_params {
uint32_t central_freq;
};
static void skl_wrpll_params_populate(struct skl_wrpll_params *params,
uint64_t afe_clock,
uint64_t central_freq,
uint32_t p0, uint32_t p1, uint32_t p2)
{
uint64_t dco_freq;
params->central_freq = central_freq;
switch (central_freq) {
case 9600000000ULL:
params->central_freq = 0;
break;
case 9000000000ULL:
params->central_freq = 1;
break;
case 8400000000ULL:
params->central_freq = 3;
}
switch (p0) {
case 1:
params->pdiv = 0;
break;
case 2:
params->pdiv = 1;
break;
case 3:
params->pdiv = 2;
break;
case 7:
params->pdiv = 4;
break;
default:
WARN(1, "Incorrect PDiv\n");
}
switch (p2) {
case 5:
params->kdiv = 0;
break;
case 2:
params->kdiv = 1;
break;
case 3:
params->kdiv = 2;
break;
case 1:
params->kdiv = 3;
break;
default:
WARN(1, "Incorrect KDiv\n");
}
params->qdiv_ratio = p1;
params->qdiv_mode = (params->qdiv_ratio == 1) ? 0 : 1;
dco_freq = p0 * p1 * p2 * afe_clock;
/*
* Intermediate values are in Hz.
* Divide by MHz to match bsepc
*/
params->dco_integer = div_u64(dco_freq, (24 * MHz(1)));
params->dco_fraction =
div_u64(((div_u64(dco_freq, 24) -
params->dco_integer * MHz(1)) * 0x8000), MHz(1));
}
static bool
skl_ddi_calculate_wrpll(int clock /* in Hz */,
struct skl_wrpll_params *wrpll_params)
@ -1134,7 +1203,6 @@ skl_ddi_calculate_wrpll(int clock /* in Hz */,
uint32_t dco_central_freq_deviation[3];
uint32_t i, P1, k, dco_count;
bool retry_with_odd = false;
uint64_t dco_freq;
/* Determine P0, P1 or P2 */
for (dco_count = 0; dco_count < 3; dco_count++) {
@ -1197,69 +1265,12 @@ found:
"No valid parameters found for pixel clock: %dHz\n", clock))
return false;
wrpll_params->central_freq = dco_central_freq[min_dco_index];
switch (dco_central_freq[min_dco_index]) {
case 9600000000ULL:
wrpll_params->central_freq = 0;
break;
case 9000000000ULL:
wrpll_params->central_freq = 1;
break;
case 8400000000ULL:
wrpll_params->central_freq = 3;
}
switch (candidate_p0[min_dco_index]) {
case 1:
wrpll_params->pdiv = 0;
break;
case 2:
wrpll_params->pdiv = 1;
break;
case 3:
wrpll_params->pdiv = 2;
break;
case 7:
wrpll_params->pdiv = 4;
break;
default:
WARN(1, "Incorrect PDiv\n");
}
switch (candidate_p2[min_dco_index]) {
case 5:
wrpll_params->kdiv = 0;
break;
case 2:
wrpll_params->kdiv = 1;
break;
case 3:
wrpll_params->kdiv = 2;
break;
case 1:
wrpll_params->kdiv = 3;
break;
default:
WARN(1, "Incorrect KDiv\n");
}
wrpll_params->qdiv_ratio = candidate_p1[min_dco_index];
wrpll_params->qdiv_mode =
(wrpll_params->qdiv_ratio == 1) ? 0 : 1;
dco_freq = candidate_p0[min_dco_index] *
candidate_p1[min_dco_index] *
candidate_p2[min_dco_index] * afe_clock;
/*
* Intermediate values are in Hz.
* Divide by MHz to match bsepc
*/
wrpll_params->dco_integer = div_u64(dco_freq, (24 * MHz(1)));
wrpll_params->dco_fraction =
div_u64(((div_u64(dco_freq, 24) -
wrpll_params->dco_integer * MHz(1)) * 0x8000), MHz(1));
skl_wrpll_params_populate(wrpll_params,
afe_clock,
dco_central_freq[min_dco_index],
candidate_p0[min_dco_index],
candidate_p1[min_dco_index],
candidate_p2[min_dco_index]);
return true;
}