From e5fd91f1ef340da553f7a79da9540c3db711c937 Mon Sep 17 00:00:00 2001 From: André Fabian Silva Delgado Date: Tue, 8 Sep 2015 01:01:14 -0300 Subject: Linux-libre 4.2-gnu --- drivers/gpu/drm/amd/amdgpu/amdgpu_pll.c | 350 ++++++++++++++++++++++++++++++++ 1 file changed, 350 insertions(+) create mode 100644 drivers/gpu/drm/amd/amdgpu/amdgpu_pll.c (limited to 'drivers/gpu/drm/amd/amdgpu/amdgpu_pll.c') diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_pll.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_pll.c new file mode 100644 index 000000000..d15314957 --- /dev/null +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_pll.c @@ -0,0 +1,350 @@ +/* + * Copyright 2014 Advanced Micro Devices, Inc. + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sublicense, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in + * all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR + * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, + * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR + * OTHER DEALINGS IN THE SOFTWARE. + * + */ +#include +#include +#include "amdgpu.h" +#include "atom.h" +#include "atombios_encoders.h" +#include +#include + +/** + * amdgpu_pll_reduce_ratio - fractional number reduction + * + * @nom: nominator + * @den: denominator + * @nom_min: minimum value for nominator + * @den_min: minimum value for denominator + * + * Find the greatest common divisor and apply it on both nominator and + * denominator, but make nominator and denominator are at least as large + * as their minimum values. + */ +static void amdgpu_pll_reduce_ratio(unsigned *nom, unsigned *den, + unsigned nom_min, unsigned den_min) +{ + unsigned tmp; + + /* reduce the numbers to a simpler ratio */ + tmp = gcd(*nom, *den); + *nom /= tmp; + *den /= tmp; + + /* make sure nominator is large enough */ + if (*nom < nom_min) { + tmp = DIV_ROUND_UP(nom_min, *nom); + *nom *= tmp; + *den *= tmp; + } + + /* make sure the denominator is large enough */ + if (*den < den_min) { + tmp = DIV_ROUND_UP(den_min, *den); + *nom *= tmp; + *den *= tmp; + } +} + +/** + * amdgpu_pll_get_fb_ref_div - feedback and ref divider calculation + * + * @nom: nominator + * @den: denominator + * @post_div: post divider + * @fb_div_max: feedback divider maximum + * @ref_div_max: reference divider maximum + * @fb_div: resulting feedback divider + * @ref_div: resulting reference divider + * + * Calculate feedback and reference divider for a given post divider. Makes + * sure we stay within the limits. + */ +static void amdgpu_pll_get_fb_ref_div(unsigned nom, unsigned den, unsigned post_div, + unsigned fb_div_max, unsigned ref_div_max, + unsigned *fb_div, unsigned *ref_div) +{ + /* limit reference * post divider to a maximum */ + ref_div_max = min(128 / post_div, ref_div_max); + + /* get matching reference and feedback divider */ + *ref_div = min(max(DIV_ROUND_CLOSEST(den, post_div), 1u), ref_div_max); + *fb_div = DIV_ROUND_CLOSEST(nom * *ref_div * post_div, den); + + /* limit fb divider to its maximum */ + if (*fb_div > fb_div_max) { + *ref_div = DIV_ROUND_CLOSEST(*ref_div * fb_div_max, *fb_div); + *fb_div = fb_div_max; + } +} + +/** + * amdgpu_pll_compute - compute PLL paramaters + * + * @pll: information about the PLL + * @dot_clock_p: resulting pixel clock + * fb_div_p: resulting feedback divider + * frac_fb_div_p: fractional part of the feedback divider + * ref_div_p: resulting reference divider + * post_div_p: resulting reference divider + * + * Try to calculate the PLL parameters to generate the given frequency: + * dot_clock = (ref_freq * feedback_div) / (ref_div * post_div) + */ +void amdgpu_pll_compute(struct amdgpu_pll *pll, + u32 freq, + u32 *dot_clock_p, + u32 *fb_div_p, + u32 *frac_fb_div_p, + u32 *ref_div_p, + u32 *post_div_p) +{ + unsigned target_clock = pll->flags & AMDGPU_PLL_USE_FRAC_FB_DIV ? + freq : freq / 10; + + unsigned fb_div_min, fb_div_max, fb_div; + unsigned post_div_min, post_div_max, post_div; + unsigned ref_div_min, ref_div_max, ref_div; + unsigned post_div_best, diff_best; + unsigned nom, den; + + /* determine allowed feedback divider range */ + fb_div_min = pll->min_feedback_div; + fb_div_max = pll->max_feedback_div; + + if (pll->flags & AMDGPU_PLL_USE_FRAC_FB_DIV) { + fb_div_min *= 10; + fb_div_max *= 10; + } + + /* determine allowed ref divider range */ + if (pll->flags & AMDGPU_PLL_USE_REF_DIV) + ref_div_min = pll->reference_div; + else + ref_div_min = pll->min_ref_div; + + if (pll->flags & AMDGPU_PLL_USE_FRAC_FB_DIV && + pll->flags & AMDGPU_PLL_USE_REF_DIV) + ref_div_max = pll->reference_div; + else + ref_div_max = pll->max_ref_div; + + /* determine allowed post divider range */ + if (pll->flags & AMDGPU_PLL_USE_POST_DIV) { + post_div_min = pll->post_div; + post_div_max = pll->post_div; + } else { + unsigned vco_min, vco_max; + + if (pll->flags & AMDGPU_PLL_IS_LCD) { + vco_min = pll->lcd_pll_out_min; + vco_max = pll->lcd_pll_out_max; + } else { + vco_min = pll->pll_out_min; + vco_max = pll->pll_out_max; + } + + if (pll->flags & AMDGPU_PLL_USE_FRAC_FB_DIV) { + vco_min *= 10; + vco_max *= 10; + } + + post_div_min = vco_min / target_clock; + if ((target_clock * post_div_min) < vco_min) + ++post_div_min; + if (post_div_min < pll->min_post_div) + post_div_min = pll->min_post_div; + + post_div_max = vco_max / target_clock; + if ((target_clock * post_div_max) > vco_max) + --post_div_max; + if (post_div_max > pll->max_post_div) + post_div_max = pll->max_post_div; + } + + /* represent the searched ratio as fractional number */ + nom = target_clock; + den = pll->reference_freq; + + /* reduce the numbers to a simpler ratio */ + amdgpu_pll_reduce_ratio(&nom, &den, fb_div_min, post_div_min); + + /* now search for a post divider */ + if (pll->flags & AMDGPU_PLL_PREFER_MINM_OVER_MAXP) + post_div_best = post_div_min; + else + post_div_best = post_div_max; + diff_best = ~0; + + for (post_div = post_div_min; post_div <= post_div_max; ++post_div) { + unsigned diff; + amdgpu_pll_get_fb_ref_div(nom, den, post_div, fb_div_max, + ref_div_max, &fb_div, &ref_div); + diff = abs(target_clock - (pll->reference_freq * fb_div) / + (ref_div * post_div)); + + if (diff < diff_best || (diff == diff_best && + !(pll->flags & AMDGPU_PLL_PREFER_MINM_OVER_MAXP))) { + + post_div_best = post_div; + diff_best = diff; + } + } + post_div = post_div_best; + + /* get the feedback and reference divider for the optimal value */ + amdgpu_pll_get_fb_ref_div(nom, den, post_div, fb_div_max, ref_div_max, + &fb_div, &ref_div); + + /* reduce the numbers to a simpler ratio once more */ + /* this also makes sure that the reference divider is large enough */ + amdgpu_pll_reduce_ratio(&fb_div, &ref_div, fb_div_min, ref_div_min); + + /* avoid high jitter with small fractional dividers */ + if (pll->flags & AMDGPU_PLL_USE_FRAC_FB_DIV && (fb_div % 10)) { + fb_div_min = max(fb_div_min, (9 - (fb_div % 10)) * 20 + 60); + if (fb_div < fb_div_min) { + unsigned tmp = DIV_ROUND_UP(fb_div_min, fb_div); + fb_div *= tmp; + ref_div *= tmp; + } + } + + /* and finally save the result */ + if (pll->flags & AMDGPU_PLL_USE_FRAC_FB_DIV) { + *fb_div_p = fb_div / 10; + *frac_fb_div_p = fb_div % 10; + } else { + *fb_div_p = fb_div; + *frac_fb_div_p = 0; + } + + *dot_clock_p = ((pll->reference_freq * *fb_div_p * 10) + + (pll->reference_freq * *frac_fb_div_p)) / + (ref_div * post_div * 10); + *ref_div_p = ref_div; + *post_div_p = post_div; + + DRM_DEBUG_KMS("%d - %d, pll dividers - fb: %d.%d ref: %d, post %d\n", + freq, *dot_clock_p * 10, *fb_div_p, *frac_fb_div_p, + ref_div, post_div); +} + +/** + * amdgpu_pll_get_use_mask - look up a mask of which pplls are in use + * + * @crtc: drm crtc + * + * Returns the mask of which PPLLs (Pixel PLLs) are in use. + */ +u32 amdgpu_pll_get_use_mask(struct drm_crtc *crtc) +{ + struct drm_device *dev = crtc->dev; + struct drm_crtc *test_crtc; + struct amdgpu_crtc *test_amdgpu_crtc; + u32 pll_in_use = 0; + + list_for_each_entry(test_crtc, &dev->mode_config.crtc_list, head) { + if (crtc == test_crtc) + continue; + + test_amdgpu_crtc = to_amdgpu_crtc(test_crtc); + if (test_amdgpu_crtc->pll_id != ATOM_PPLL_INVALID) + pll_in_use |= (1 << test_amdgpu_crtc->pll_id); + } + return pll_in_use; +} + +/** + * amdgpu_pll_get_shared_dp_ppll - return the PPLL used by another crtc for DP + * + * @crtc: drm crtc + * + * Returns the PPLL (Pixel PLL) used by another crtc/encoder which is + * also in DP mode. For DP, a single PPLL can be used for all DP + * crtcs/encoders. + */ +int amdgpu_pll_get_shared_dp_ppll(struct drm_crtc *crtc) +{ + struct drm_device *dev = crtc->dev; + struct drm_crtc *test_crtc; + struct amdgpu_crtc *test_amdgpu_crtc; + + list_for_each_entry(test_crtc, &dev->mode_config.crtc_list, head) { + if (crtc == test_crtc) + continue; + test_amdgpu_crtc = to_amdgpu_crtc(test_crtc); + if (test_amdgpu_crtc->encoder && + ENCODER_MODE_IS_DP(amdgpu_atombios_encoder_get_encoder_mode(test_amdgpu_crtc->encoder))) { + /* for DP use the same PLL for all */ + if (test_amdgpu_crtc->pll_id != ATOM_PPLL_INVALID) + return test_amdgpu_crtc->pll_id; + } + } + return ATOM_PPLL_INVALID; +} + +/** + * amdgpu_pll_get_shared_nondp_ppll - return the PPLL used by another non-DP crtc + * + * @crtc: drm crtc + * @encoder: drm encoder + * + * Returns the PPLL (Pixel PLL) used by another non-DP crtc/encoder which can + * be shared (i.e., same clock). + */ +int amdgpu_pll_get_shared_nondp_ppll(struct drm_crtc *crtc) +{ + struct amdgpu_crtc *amdgpu_crtc = to_amdgpu_crtc(crtc); + struct drm_device *dev = crtc->dev; + struct drm_crtc *test_crtc; + struct amdgpu_crtc *test_amdgpu_crtc; + u32 adjusted_clock, test_adjusted_clock; + + adjusted_clock = amdgpu_crtc->adjusted_clock; + + if (adjusted_clock == 0) + return ATOM_PPLL_INVALID; + + list_for_each_entry(test_crtc, &dev->mode_config.crtc_list, head) { + if (crtc == test_crtc) + continue; + test_amdgpu_crtc = to_amdgpu_crtc(test_crtc); + if (test_amdgpu_crtc->encoder && + !ENCODER_MODE_IS_DP(amdgpu_atombios_encoder_get_encoder_mode(test_amdgpu_crtc->encoder))) { + /* check if we are already driving this connector with another crtc */ + if (test_amdgpu_crtc->connector == amdgpu_crtc->connector) { + /* if we are, return that pll */ + if (test_amdgpu_crtc->pll_id != ATOM_PPLL_INVALID) + return test_amdgpu_crtc->pll_id; + } + /* for non-DP check the clock */ + test_adjusted_clock = test_amdgpu_crtc->adjusted_clock; + if ((crtc->mode.clock == test_crtc->mode.clock) && + (adjusted_clock == test_adjusted_clock) && + (amdgpu_crtc->ss_enabled == test_amdgpu_crtc->ss_enabled) && + (test_amdgpu_crtc->pll_id != ATOM_PPLL_INVALID)) + return test_amdgpu_crtc->pll_id; + } + } + return ATOM_PPLL_INVALID; +} -- cgit v1.2.3-54-g00ecf