From: Nicholas Kazlauskas Date: Thu, 9 May 2019 16:14:58 +0000 (-0400) Subject: drm/amd/display: Rework CRTC color management X-Git-Url: http://git.cdn.openwrt.org/?a=commitdiff_plain;h=cf020d49b3c4ef6ab6f26be3dbf2f36b3df9f797;p=openwrt%2Fstaging%2Fblogic.git drm/amd/display: Rework CRTC color management [Why] To prepare for the upcoming DRM plane color management properties we need to correct a lot of wrong behavior and assumptions made for CRTC color management. The documentation added by this commit in amdgpu_dm_color explains how the HW color pipeline works and its limitations with the DRM interface. The current implementation does the following wrong: - Implicit sRGB DGM when no CRTC DGM is set - Implicit sRGB RGM when no CRTC RGM is set - No way to specify a non-linear DGM matrix that produces correct output - No way to specify a correct RGM when a linear DGM is used We had workarounds for passing kms_color tests but not all of the behavior we had wrong was covered by these tests (especially when it comes to non-linear DGM). Testing both DGM and RGM at the same time isn't something kms_color tests well either. [How] The specifics for how color management works in AMDGPU and the new behavior can be found by reading the documentation added to amdgpu_dm_color.c from this patch. All of the incorrect cases from the old implementation have been addressed for the atomic interface, but there still a few TODOs for the legacy one. Note: this does cause regressions for kms_color@pipe-a-ctm-* over HDMI. The result looks correct from visual inspection but the CRC no longer matches. For reference, the test was previously doing the following: linear degamma -> CTM -> sRGB regamma -> RGB to YUV (709) -> ... Now the test is doing: linear degamma -> CTM -> linear regamma -> RGB to YUV (709) -> ... Signed-off-by: Nicholas Kazlauskas Reviewed-by: Sun peng Li Acked-by: Bhawanpreet Lakha Signed-off-by: Alex Deucher --- diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c index 07967497fb34..58d7bbc5ada7 100644 --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c @@ -2878,6 +2878,7 @@ static int fill_dc_plane_attributes(struct amdgpu_device *adev, struct drm_plane_state *plane_state, struct drm_crtc_state *crtc_state) { + struct dm_crtc_state *dm_crtc_state = to_dm_crtc_state(crtc_state); const struct amdgpu_framebuffer *amdgpu_fb = to_amdgpu_framebuffer(plane_state->fb); struct dc_scaling_info scaling_info; @@ -2922,13 +2923,11 @@ static int fill_dc_plane_attributes(struct amdgpu_device *adev, * Always set input transfer function, since plane state is refreshed * every time. */ - ret = amdgpu_dm_set_degamma_lut(crtc_state, dc_plane_state); - if (ret) { - dc_transfer_func_release(dc_plane_state->in_transfer_func); - dc_plane_state->in_transfer_func = NULL; - } + ret = amdgpu_dm_update_plane_color_mgmt(dm_crtc_state, dc_plane_state); + if (ret) + return ret; - return ret; + return 0; } static void update_stream_scaling_settings(const struct drm_display_mode *mode, @@ -3517,6 +3516,8 @@ dm_crtc_duplicate_state(struct drm_crtc *crtc) state->vrr_supported = cur->vrr_supported; state->freesync_config = cur->freesync_config; state->crc_enabled = cur->crc_enabled; + state->cm_has_degamma = cur->cm_has_degamma; + state->cm_is_degamma_srgb = cur->cm_is_degamma_srgb; /* TODO Duplicate dc_stream after objects are stream object is flattened */ @@ -5674,8 +5675,18 @@ static void amdgpu_dm_commit_planes(struct drm_atomic_state *state, bundle->stream_update.dst = acrtc_state->stream->dst; } - if (new_pcrtc_state->color_mgmt_changed) - bundle->stream_update.out_transfer_func = acrtc_state->stream->out_transfer_func; + if (new_pcrtc_state->color_mgmt_changed) { + /* + * TODO: This isn't fully correct since we've actually + * already modified the stream in place. + */ + bundle->stream_update.gamut_remap = + &acrtc_state->stream->gamut_remap_matrix; + bundle->stream_update.output_csc_transform = + &acrtc_state->stream->csc_color_matrix; + bundle->stream_update.out_transfer_func = + acrtc_state->stream->out_transfer_func; + } acrtc_state->stream->abm_level = acrtc_state->abm_level; if (acrtc_state->abm_level != dm_old_crtc_state->abm_level) @@ -6525,10 +6536,9 @@ skip_modeset: */ if (dm_new_crtc_state->base.color_mgmt_changed || drm_atomic_crtc_needs_modeset(new_crtc_state)) { - ret = amdgpu_dm_set_regamma_lut(dm_new_crtc_state); + ret = amdgpu_dm_update_crtc_color_mgmt(dm_new_crtc_state); if (ret) goto fail; - amdgpu_dm_set_ctm(dm_new_crtc_state); } /* Update Freesync settings. */ @@ -6831,6 +6841,8 @@ dm_determine_update_type_for_commit(struct amdgpu_display_manager *dm, new_dm_plane_state->dc_state->in_transfer_func; stream_update.gamut_remap = &new_dm_crtc_state->stream->gamut_remap_matrix; + stream_update.output_csc_transform = + &new_dm_crtc_state->stream->csc_color_matrix; stream_update.out_transfer_func = new_dm_crtc_state->stream->out_transfer_func; } diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h index 59d2584e556e..b2ae6560279c 100644 --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h @@ -278,6 +278,9 @@ struct dm_crtc_state { struct drm_crtc_state base; struct dc_stream_state *stream; + bool cm_has_degamma; + bool cm_is_degamma_srgb; + int active_planes; bool interrupts_enabled; @@ -367,10 +370,9 @@ void amdgpu_dm_crtc_handle_crc_irq(struct drm_crtc *crtc); #define MAX_COLOR_LEGACY_LUT_ENTRIES 256 void amdgpu_dm_init_color_mod(void); -int amdgpu_dm_set_degamma_lut(struct drm_crtc_state *crtc_state, - struct dc_plane_state *dc_plane_state); -void amdgpu_dm_set_ctm(struct dm_crtc_state *crtc); -int amdgpu_dm_set_regamma_lut(struct dm_crtc_state *crtc); +int amdgpu_dm_update_crtc_color_mgmt(struct dm_crtc_state *crtc); +int amdgpu_dm_update_plane_color_mgmt(struct dm_crtc_state *crtc, + struct dc_plane_state *dc_plane_state); extern const struct drm_encoder_helper_funcs amdgpu_dm_encoder_helper_funcs; diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_color.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_color.c index 75b6a2ac910b..b43bb7f90e4e 100644 --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_color.c +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_color.c @@ -27,6 +27,47 @@ #include "amdgpu_dm.h" #include "dc.h" #include "modules/color/color_gamma.h" +#include "basics/conversion.h" + +/* + * The DC interface to HW gives us the following color management blocks + * per pipe (surface): + * + * - Input gamma LUT (de-normalized) + * - Input CSC (normalized) + * - Surface degamma LUT (normalized) + * - Surface CSC (normalized) + * - Surface regamma LUT (normalized) + * - Output CSC (normalized) + * + * But these aren't a direct mapping to DRM color properties. The current DRM + * interface exposes CRTC degamma, CRTC CTM and CRTC regamma while our hardware + * is essentially giving: + * + * Plane CTM -> Plane degamma -> Plane CTM -> Plane regamma -> Plane CTM + * + * The input gamma LUT block isn't really applicable here since it operates + * on the actual input data itself rather than the HW fp representation. The + * input and output CSC blocks are technically available to use as part of + * the DC interface but are typically used internally by DC for conversions + * between color spaces. These could be blended together with user + * adjustments in the future but for now these should remain untouched. + * + * The pipe blending also happens after these blocks so we don't actually + * support any CRTC props with correct blending with multiple planes - but we + * can still support CRTC color management properties in DM in most single + * plane cases correctly with clever management of the DC interface in DM. + * + * As per DRM documentation, blocks should be in hardware bypass when their + * respective property is set to NULL. A linear DGM/RGM LUT should also + * considered as putting the respective block into bypass mode. + * + * This means that the following + * configuration is assumed to be the default: + * + * Plane DGM Bypass -> Plane CTM Bypass -> Plane RGM Bypass -> ... + * CRTC DGM Bypass -> CRTC CTM Bypass -> CRTC RGM Bypass + */ #define MAX_DRM_LUT_VALUE 0xFFFF @@ -41,6 +82,13 @@ void amdgpu_dm_init_color_mod(void) setup_x_points_distribution(); } +/* Extracts the DRM lut and lut size from a blob. */ +static const struct drm_color_lut * +__extract_blob_lut(const struct drm_property_blob *blob, uint32_t *size) +{ + *size = blob ? drm_color_lut_size(blob) : 0; + return blob ? (struct drm_color_lut *)blob->data : NULL; +} /* * Return true if the given lut is a linear mapping of values, i.e. it acts @@ -50,7 +98,7 @@ void amdgpu_dm_init_color_mod(void) * f(a) = (0xFF00/MAX_COLOR_LUT_ENTRIES-1)a; for integer a in * [0, MAX_COLOR_LUT_ENTRIES) */ -static bool __is_lut_linear(struct drm_color_lut *lut, uint32_t size) +static bool __is_lut_linear(const struct drm_color_lut *lut, uint32_t size) { int i; uint32_t expected; @@ -75,9 +123,8 @@ static bool __is_lut_linear(struct drm_color_lut *lut, uint32_t size) * Convert the drm_color_lut to dc_gamma. The conversion depends on the size * of the lut - whether or not it's legacy. */ -static void __drm_lut_to_dc_gamma(struct drm_color_lut *lut, - struct dc_gamma *gamma, - bool is_legacy) +static void __drm_lut_to_dc_gamma(const struct drm_color_lut *lut, + struct dc_gamma *gamma, bool is_legacy) { uint32_t r, g, b; int i; @@ -107,103 +154,16 @@ static void __drm_lut_to_dc_gamma(struct drm_color_lut *lut, } } -/** - * amdgpu_dm_set_regamma_lut: Set regamma lut for the given CRTC. - * @crtc: amdgpu_dm crtc state - * - * Update the underlying dc_stream_state's output transfer function (OTF) in - * preparation for hardware commit. If no lut is specified by user, we default - * to SRGB. - * - * RETURNS: - * 0 on success, -ENOMEM if memory cannot be allocated to calculate the OTF. - */ -int amdgpu_dm_set_regamma_lut(struct dm_crtc_state *crtc) -{ - struct drm_property_blob *blob = crtc->base.gamma_lut; - struct dc_stream_state *stream = crtc->stream; - struct amdgpu_device *adev = (struct amdgpu_device *) - crtc->base.state->dev->dev_private; - struct drm_color_lut *lut; - uint32_t lut_size; - struct dc_gamma *gamma = NULL; - enum dc_transfer_func_type old_type = stream->out_transfer_func->type; - - bool ret; - - if (!blob && adev->asic_type <= CHIP_RAVEN) { - /* By default, use the SRGB predefined curve.*/ - stream->out_transfer_func->type = TF_TYPE_PREDEFINED; - stream->out_transfer_func->tf = TRANSFER_FUNCTION_SRGB; - return 0; - } - - if (blob) { - lut = (struct drm_color_lut *)blob->data; - lut_size = blob->length / sizeof(struct drm_color_lut); - - gamma = dc_create_gamma(); - if (!gamma) - return -ENOMEM; - - gamma->num_entries = lut_size; - if (gamma->num_entries == MAX_COLOR_LEGACY_LUT_ENTRIES) - gamma->type = GAMMA_RGB_256; - else if (gamma->num_entries == MAX_COLOR_LUT_ENTRIES) - gamma->type = GAMMA_CS_TFM_1D; - else { - /* Invalid lut size */ - dc_gamma_release(&gamma); - return -EINVAL; - } - - /* Convert drm_lut into dc_gamma */ - __drm_lut_to_dc_gamma(lut, gamma, gamma->type == GAMMA_RGB_256); - } - - /* predefined gamma ROM only exist for RAVEN and pre-RAVEN ASIC, - * set canRomBeUsed accordingly - */ - stream->out_transfer_func->type = TF_TYPE_DISTRIBUTED_POINTS; - ret = mod_color_calculate_regamma_params(stream->out_transfer_func, - gamma, true, adev->asic_type <= CHIP_NAVI10, NULL); - - if (gamma) - dc_gamma_release(&gamma); - - if (!ret) { - stream->out_transfer_func->type = old_type; - DRM_ERROR("Out of memory when calculating regamma params\n"); - return -ENOMEM; - } - - return 0; -} - -/** - * amdgpu_dm_set_ctm: Set the color transform matrix for the given CRTC. - * @crtc: amdgpu_dm crtc state - * - * Update the underlying dc_stream_state's gamut remap matrix in preparation - * for hardware commit. If no matrix is specified by user, gamut remap will be - * disabled. +/* + * Converts a DRM CTM to a DC CSC float matrix. + * The matrix needs to be a 3x4 (12 entry) matrix. */ -void amdgpu_dm_set_ctm(struct dm_crtc_state *crtc) +static void __drm_ctm_to_dc_matrix(const struct drm_color_ctm *ctm, + struct fixed31_32 *matrix) { - - struct drm_property_blob *blob = crtc->base.ctm; - struct dc_stream_state *stream = crtc->stream; - struct drm_color_ctm *ctm; int64_t val; int i; - if (!blob) { - stream->gamut_remap_matrix.enable_remap = false; - return; - } - - stream->gamut_remap_matrix.enable_remap = true; - ctm = (struct drm_color_ctm *)blob->data; /* * DRM gives a 3x3 matrix, but DC wants 3x4. Assuming we're operating * with homogeneous coordinates, augment the matrix with 0's. @@ -215,83 +175,306 @@ void amdgpu_dm_set_ctm(struct dm_crtc_state *crtc) for (i = 0; i < 12; i++) { /* Skip 4th element */ if (i % 4 == 3) { - stream->gamut_remap_matrix.matrix[i] = dc_fixpt_zero; + matrix[i] = dc_fixpt_zero; continue; } /* gamut_remap_matrix[i] = ctm[i - floor(i/4)] */ - val = ctm->matrix[i - (i/4)]; + val = ctm->matrix[i - (i / 4)]; /* If negative, convert to 2's complement. */ if (val & (1ULL << 63)) val = -(val & ~(1ULL << 63)); - stream->gamut_remap_matrix.matrix[i].value = val; + matrix[i].value = val; } } +/* Calculates the legacy transfer function - only for sRGB input space. */ +static int __set_legacy_tf(struct dc_transfer_func *func, + const struct drm_color_lut *lut, uint32_t lut_size, + bool has_rom) +{ + struct dc_gamma *gamma = NULL; + bool res; -/** - * amdgpu_dm_set_degamma_lut: Set degamma lut for the given CRTC. - * @crtc: amdgpu_dm crtc state - * - * Update the underlying dc_stream_state's input transfer function (ITF) in - * preparation for hardware commit. If no lut is specified by user, we default - * to SRGB degamma. - * - * We support degamma bypass, predefined SRGB, and custom degamma - * - * RETURNS: - * 0 on success - * -EINVAL if crtc_state has a degamma_lut of invalid size - * -ENOMEM if gamma allocation fails - */ -int amdgpu_dm_set_degamma_lut(struct drm_crtc_state *crtc_state, - struct dc_plane_state *dc_plane_state) + ASSERT(lut && lut_size == MAX_COLOR_LEGACY_LUT_ENTRIES); + + gamma = dc_create_gamma(); + if (!gamma) + return -ENOMEM; + + gamma->type = GAMMA_RGB_256; + gamma->num_entries = lut_size; + __drm_lut_to_dc_gamma(lut, gamma, true); + + res = mod_color_calculate_regamma_params(func, gamma, true, has_rom, + NULL); + + return res ? 0 : -ENOMEM; +} + +/* Calculates the output transfer function based on expected input space. */ +static int __set_output_tf(struct dc_transfer_func *func, + const struct drm_color_lut *lut, uint32_t lut_size, + bool has_rom) { - struct drm_property_blob *blob = crtc_state->degamma_lut; - struct drm_color_lut *lut; - uint32_t lut_size; - struct dc_gamma *gamma; - bool ret; - - if (!blob) { - /* Default to SRGB */ - dc_plane_state->in_transfer_func->type = TF_TYPE_PREDEFINED; - dc_plane_state->in_transfer_func->tf = TRANSFER_FUNCTION_SRGB; - return 0; - } + struct dc_gamma *gamma = NULL; + bool res; - lut = (struct drm_color_lut *)blob->data; - if (__is_lut_linear(lut, MAX_COLOR_LUT_ENTRIES)) { - dc_plane_state->in_transfer_func->type = TF_TYPE_BYPASS; - dc_plane_state->in_transfer_func->tf = TRANSFER_FUNCTION_LINEAR; - return 0; - } + ASSERT(lut && lut_size == MAX_COLOR_LUT_ENTRIES); gamma = dc_create_gamma(); if (!gamma) return -ENOMEM; - lut_size = blob->length / sizeof(struct drm_color_lut); gamma->num_entries = lut_size; - if (gamma->num_entries == MAX_COLOR_LUT_ENTRIES) + __drm_lut_to_dc_gamma(lut, gamma, false); + + if (func->tf == TRANSFER_FUNCTION_LINEAR) { + /* + * Color module doesn't like calculating regamma params + * on top of a linear input. But degamma params can be used + * instead to simulate this. + */ gamma->type = GAMMA_CUSTOM; - else { - dc_gamma_release(&gamma); - return -EINVAL; + res = mod_color_calculate_degamma_params(func, gamma, true); + } else { + /* + * Assume sRGB. The actual mapping will depend on whether the + * input was legacy or not. + */ + gamma->type = GAMMA_CS_TFM_1D; + res = mod_color_calculate_regamma_params(func, gamma, false, + has_rom, NULL); } + dc_gamma_release(&gamma); + + return res ? 0 : -ENOMEM; +} + +/* Caculates the input transfer function based on expected input space. */ +static int __set_input_tf(struct dc_transfer_func *func, + const struct drm_color_lut *lut, uint32_t lut_size) +{ + struct dc_gamma *gamma = NULL; + bool res; + + gamma = dc_create_gamma(); + if (!gamma) + return -ENOMEM; + + gamma->type = GAMMA_CUSTOM; + gamma->num_entries = lut_size; + __drm_lut_to_dc_gamma(lut, gamma, false); - dc_plane_state->in_transfer_func->type = TF_TYPE_DISTRIBUTED_POINTS; - ret = mod_color_calculate_degamma_params(dc_plane_state->in_transfer_func, gamma, true); + res = mod_color_calculate_degamma_params(func, gamma, true); dc_gamma_release(&gamma); - if (!ret) { - dc_plane_state->in_transfer_func->type = TF_TYPE_BYPASS; - DRM_ERROR("Out of memory when calculating degamma params\n"); - return -ENOMEM; + + return res ? 0 : -ENOMEM; +} + +/** + * amdgpu_dm_update_crtc_color_mgmt: Maps DRM color management to DC stream. + * @crtc: amdgpu_dm crtc state + * + * With no plane level color management properties we're free to use any + * of the HW blocks as long as the CRTC CTM always comes before the + * CRTC RGM and after the CRTC DGM. + * + * The CRTC RGM block will be placed in the RGM LUT block if it is non-linear. + * The CRTC DGM block will be placed in the DGM LUT block if it is non-linear. + * The CRTC CTM will be placed in the gamut remap block if it is non-linear. + * + * The RGM block is typically more fully featured and accurate across + * all ASICs - DCE can't support a custom non-linear CRTC DGM. + * + * For supporting both plane level color management and CRTC level color + * management at once we have to either restrict the usage of CRTC properties + * or blend adjustments together. + * + * Returns 0 on success. + */ +int amdgpu_dm_update_crtc_color_mgmt(struct dm_crtc_state *crtc) +{ + struct dc_stream_state *stream = crtc->stream; + struct amdgpu_device *adev = + (struct amdgpu_device *)crtc->base.state->dev->dev_private; + bool has_rom = adev->asic_type <= CHIP_RAVEN; + struct drm_color_ctm *ctm = NULL; + const struct drm_color_lut *degamma_lut, *regamma_lut; + uint32_t degamma_size, regamma_size; + bool has_regamma, has_degamma; + bool is_legacy; + int r; + + degamma_lut = __extract_blob_lut(crtc->base.degamma_lut, °amma_size); + if (degamma_lut && degamma_size != MAX_COLOR_LUT_ENTRIES) + return -EINVAL; + + regamma_lut = __extract_blob_lut(crtc->base.gamma_lut, ®amma_size); + if (regamma_lut && regamma_size != MAX_COLOR_LUT_ENTRIES && + regamma_size != MAX_COLOR_LEGACY_LUT_ENTRIES) + return -EINVAL; + + has_degamma = + degamma_lut && !__is_lut_linear(degamma_lut, degamma_size); + + has_regamma = + regamma_lut && !__is_lut_linear(regamma_lut, regamma_size); + + is_legacy = regamma_size == MAX_COLOR_LEGACY_LUT_ENTRIES; + + /* Reset all adjustments. */ + crtc->cm_has_degamma = false; + crtc->cm_is_degamma_srgb = false; + + /* Setup regamma and degamma. */ + if (is_legacy) { + /* + * Legacy regamma forces us to use the sRGB RGM as a base. + * This also means we can't use linear DGM since DGM needs + * to use sRGB as a base as well, resulting in incorrect CRTC + * DGM and CRTC CTM. + * + * TODO: Just map this to the standard regamma interface + * instead since this isn't really right. One of the cases + * where this setup currently fails is trying to do an + * inverse color ramp in legacy userspace. + */ + crtc->cm_is_degamma_srgb = true; + stream->out_transfer_func->type = TF_TYPE_DISTRIBUTED_POINTS; + stream->out_transfer_func->tf = TRANSFER_FUNCTION_SRGB; + + r = __set_legacy_tf(stream->out_transfer_func, regamma_lut, + regamma_size, has_rom); + if (r) + return r; + } else if (has_regamma) { + /* CRTC RGM goes into RGM LUT. */ + stream->out_transfer_func->type = TF_TYPE_DISTRIBUTED_POINTS; + stream->out_transfer_func->tf = TRANSFER_FUNCTION_LINEAR; + + r = __set_output_tf(stream->out_transfer_func, regamma_lut, + regamma_size, has_rom); + if (r) + return r; + } else { + /* + * No CRTC RGM means we can just put the block into bypass + * since we don't have any plane level adjustments using it. + */ + stream->out_transfer_func->type = TF_TYPE_BYPASS; + stream->out_transfer_func->tf = TRANSFER_FUNCTION_LINEAR; + } + + /* + * CRTC DGM goes into DGM LUT. It would be nice to place it + * into the RGM since it's a more featured block but we'd + * have to place the CTM in the OCSC in that case. + */ + crtc->cm_has_degamma = has_degamma; + + /* Setup CRTC CTM. */ + if (crtc->base.ctm) { + ctm = (struct drm_color_ctm *)crtc->base.ctm->data; + + /* + * Gamut remapping must be used for gamma correction + * since it comes before the regamma correction. + * + * OCSC could be used for gamma correction, but we'd need to + * blend the adjustments together with the required output + * conversion matrix - so just use the gamut remap block + * for now. + */ + __drm_ctm_to_dc_matrix(ctm, stream->gamut_remap_matrix.matrix); + + stream->gamut_remap_matrix.enable_remap = true; + stream->csc_color_matrix.enable_adjustment = false; + } else { + /* Bypass CTM. */ + stream->gamut_remap_matrix.enable_remap = false; + stream->csc_color_matrix.enable_adjustment = false; } return 0; } +/** + * amdgpu_dm_update_plane_color_mgmt: Maps DRM color management to DC plane. + * @crtc: amdgpu_dm crtc state + * @ dc_plane_state: target DC surface + * + * Update the underlying dc_stream_state's input transfer function (ITF) in + * preparation for hardware commit. The transfer function used depends on + * the prepartion done on the stream for color management. + * + * Returns 0 on success. + */ +int amdgpu_dm_update_plane_color_mgmt(struct dm_crtc_state *crtc, + struct dc_plane_state *dc_plane_state) +{ + const struct drm_color_lut *degamma_lut; + uint32_t degamma_size; + int r; + + if (crtc->cm_has_degamma) { + degamma_lut = __extract_blob_lut(crtc->base.degamma_lut, + °amma_size); + ASSERT(degamma_size == MAX_COLOR_LUT_ENTRIES); + + dc_plane_state->in_transfer_func->type = + TF_TYPE_DISTRIBUTED_POINTS; + + /* + * This case isn't fully correct, but also fairly + * uncommon. This is userspace trying to use a + * legacy gamma LUT + atomic degamma LUT + * at the same time. + * + * Legacy gamma requires the input to be in linear + * space, so that means we need to apply an sRGB + * degamma. But color module also doesn't support + * a user ramp in this case so the degamma will + * be lost. + * + * Even if we did support it, it's still not right: + * + * Input -> CRTC DGM -> sRGB DGM -> CRTC CTM -> + * sRGB RGM -> CRTC RGM -> Output + * + * The CSC will be done in the wrong space since + * we're applying an sRGB DGM on top of the CRTC + * DGM. + * + * TODO: Don't use the legacy gamma interface and just + * map these to the atomic one instead. + */ + if (crtc->cm_is_degamma_srgb) + dc_plane_state->in_transfer_func->tf = + TRANSFER_FUNCTION_SRGB; + else + dc_plane_state->in_transfer_func->tf = + TRANSFER_FUNCTION_LINEAR; + + r = __set_input_tf(dc_plane_state->in_transfer_func, + degamma_lut, degamma_size); + if (r) + return r; + } else if (crtc->cm_is_degamma_srgb) { + /* + * For legacy gamma support we need the regamma input + * in linear space. Assume that the input is sRGB. + */ + dc_plane_state->in_transfer_func->type = TF_TYPE_PREDEFINED; + dc_plane_state->in_transfer_func->tf = TRANSFER_FUNCTION_SRGB; + } else { + /* ...Otherwise we can just bypass the DGM block. */ + dc_plane_state->in_transfer_func->type = TF_TYPE_BYPASS; + dc_plane_state->in_transfer_func->tf = TRANSFER_FUNCTION_LINEAR; + } + + return 0; +}