From 02725d31371b66b97bc58b2a81f0c6dc40970598 Mon Sep 17 00:00:00 2001 From: Mihail Atanassov Date: Wed, 1 Feb 2017 14:48:50 +0000 Subject: drm: mali-dp: enable gamma support Add gamma via the DRM GAMMA_LUT/GAMMA_LUT_SIZE CRTC properties. The expected LUT size is 4096 in order to produce as accurate a set of segments as possible. This version uses only the green channel's gamma curve to set the hardware curve on DP550/650. For the sake of simplicity, it uses the same table of coefficients for all 3 curves on DP500. Signed-off-by: Mihail Atanassov Signed-off-by: Liviu Dudau --- drivers/gpu/drm/arm/malidp_crtc.c | 122 ++++++++++++++++++++++++++++++++++++-- 1 file changed, 116 insertions(+), 6 deletions(-) (limited to 'drivers/gpu/drm/arm/malidp_crtc.c') diff --git a/drivers/gpu/drm/arm/malidp_crtc.c b/drivers/gpu/drm/arm/malidp_crtc.c index ec1396f79cbd..27ab09459b9d 100644 --- a/drivers/gpu/drm/arm/malidp_crtc.c +++ b/drivers/gpu/drm/arm/malidp_crtc.c @@ -93,6 +93,108 @@ static void malidp_crtc_disable(struct drm_crtc *crtc) } } +static const struct gamma_curve_segment { + u16 start; + u16 end; +} segments[MALIDP_COEFFTAB_NUM_COEFFS] = { + /* sector 0 */ + { 0, 0 }, { 1, 1 }, { 2, 2 }, { 3, 3 }, + { 4, 4 }, { 5, 5 }, { 6, 6 }, { 7, 7 }, + { 8, 8 }, { 9, 9 }, { 10, 10 }, { 11, 11 }, + { 12, 12 }, { 13, 13 }, { 14, 14 }, { 15, 15 }, + /* sector 1 */ + { 16, 19 }, { 20, 23 }, { 24, 27 }, { 28, 31 }, + /* sector 2 */ + { 32, 39 }, { 40, 47 }, { 48, 55 }, { 56, 63 }, + /* sector 3 */ + { 64, 79 }, { 80, 95 }, { 96, 111 }, { 112, 127 }, + /* sector 4 */ + { 128, 159 }, { 160, 191 }, { 192, 223 }, { 224, 255 }, + /* sector 5 */ + { 256, 319 }, { 320, 383 }, { 384, 447 }, { 448, 511 }, + /* sector 6 */ + { 512, 639 }, { 640, 767 }, { 768, 895 }, { 896, 1023 }, + { 1024, 1151 }, { 1152, 1279 }, { 1280, 1407 }, { 1408, 1535 }, + { 1536, 1663 }, { 1664, 1791 }, { 1792, 1919 }, { 1920, 2047 }, + { 2048, 2175 }, { 2176, 2303 }, { 2304, 2431 }, { 2432, 2559 }, + { 2560, 2687 }, { 2688, 2815 }, { 2816, 2943 }, { 2944, 3071 }, + { 3072, 3199 }, { 3200, 3327 }, { 3328, 3455 }, { 3456, 3583 }, + { 3584, 3711 }, { 3712, 3839 }, { 3840, 3967 }, { 3968, 4095 }, +}; + +#define DE_COEFTAB_DATA(a, b) ((((a) & 0xfff) << 16) | (((b) & 0xfff))) + +static void malidp_generate_gamma_table(struct drm_property_blob *lut_blob, + u32 coeffs[MALIDP_COEFFTAB_NUM_COEFFS]) +{ + struct drm_color_lut *lut = (struct drm_color_lut *)lut_blob->data; + int i; + + for (i = 0; i < MALIDP_COEFFTAB_NUM_COEFFS; ++i) { + u32 a, b, delta_in, out_start, out_end; + + delta_in = segments[i].end - segments[i].start; + /* DP has 12-bit internal precision for its LUTs. */ + out_start = drm_color_lut_extract(lut[segments[i].start].green, + 12); + out_end = drm_color_lut_extract(lut[segments[i].end].green, 12); + a = (delta_in == 0) ? 0 : ((out_end - out_start) * 256) / delta_in; + b = out_start; + coeffs[i] = DE_COEFTAB_DATA(a, b); + } +} + +/* + * Check if there is a new gamma LUT and if it is of an acceptable size. Also, + * reject any LUTs that use distinct red, green, and blue curves. + */ +static int malidp_crtc_atomic_check_gamma(struct drm_crtc *crtc, + struct drm_crtc_state *state) +{ + struct malidp_crtc_state *mc = to_malidp_crtc_state(state); + struct drm_color_lut *lut; + size_t lut_size; + int i; + + if (!state->color_mgmt_changed || !state->gamma_lut) + return 0; + + if (crtc->state->gamma_lut && + (crtc->state->gamma_lut->base.id == state->gamma_lut->base.id)) + return 0; + + if (state->gamma_lut->length % sizeof(struct drm_color_lut)) + return -EINVAL; + + lut_size = state->gamma_lut->length / sizeof(struct drm_color_lut); + if (lut_size != MALIDP_GAMMA_LUT_SIZE) + return -EINVAL; + + lut = (struct drm_color_lut *)state->gamma_lut->data; + for (i = 0; i < lut_size; ++i) + if (!((lut[i].red == lut[i].green) && + (lut[i].red == lut[i].blue))) + return -EINVAL; + + if (!state->mode_changed) { + int ret; + + state->mode_changed = true; + /* + * Kerneldoc for drm_atomic_helper_check_modeset mandates that + * it be invoked when the driver sets ->mode_changed. Since + * changing the gamma LUT doesn't depend on any external + * resources, it is safe to call it only once. + */ + ret = drm_atomic_helper_check_modeset(crtc->dev, state->state); + if (ret) + return ret; + } + + malidp_generate_gamma_table(state->gamma_lut, mc->gamma_coeffs); + return 0; +} + static int malidp_crtc_atomic_check(struct drm_crtc *crtc, struct drm_crtc_state *state) { @@ -168,7 +270,7 @@ static int malidp_crtc_atomic_check(struct drm_crtc *crtc, } } - return 0; + return malidp_crtc_atomic_check_gamma(crtc, state); } static const struct drm_crtc_helper_funcs malidp_crtc_helper_funcs = { @@ -180,16 +282,19 @@ static const struct drm_crtc_helper_funcs malidp_crtc_helper_funcs = { static struct drm_crtc_state *malidp_crtc_duplicate_state(struct drm_crtc *crtc) { - struct malidp_crtc_state *state; + struct malidp_crtc_state *state, *old_state; if (WARN_ON(!crtc->state)) return NULL; + old_state = to_malidp_crtc_state(crtc->state); state = kmalloc(sizeof(*state), GFP_KERNEL); if (!state) return NULL; __drm_atomic_helper_crtc_duplicate_state(crtc, &state->base); + memcpy(state->gamma_coeffs, old_state->gamma_coeffs, + sizeof(state->gamma_coeffs)); return &state->base; } @@ -244,6 +349,7 @@ static void malidp_crtc_disable_vblank(struct drm_crtc *crtc) } static const struct drm_crtc_funcs malidp_crtc_funcs = { + .gamma_set = drm_atomic_helper_legacy_gamma_set, .destroy = drm_crtc_cleanup, .set_config = drm_atomic_helper_set_config, .page_flip = drm_atomic_helper_page_flip, @@ -281,11 +387,15 @@ int malidp_crtc_init(struct drm_device *drm) ret = drm_crtc_init_with_planes(drm, &malidp->crtc, primary, NULL, &malidp_crtc_funcs, NULL); + if (ret) + goto crtc_cleanup_planes; - if (!ret) { - drm_crtc_helper_add(&malidp->crtc, &malidp_crtc_helper_funcs); - return 0; - } + drm_crtc_helper_add(&malidp->crtc, &malidp_crtc_helper_funcs); + drm_mode_crtc_set_gamma_size(&malidp->crtc, MALIDP_GAMMA_LUT_SIZE); + /* No inverse-gamma and color adjustments yet. */ + drm_crtc_enable_color_mgmt(&malidp->crtc, 0, false, MALIDP_GAMMA_LUT_SIZE); + + return 0; crtc_cleanup_planes: malidp_de_planes_destroy(drm); -- cgit v1.2.3-59-g8ed1b