LTDC 40100 hw version supports the YCbCr 422 output, reducing the output pins from 24 to 16. This feature is useful for some external devices like HDMI bridges.

Both ITU-R BT.601 & ITU-R BT.709 are supported.

It is also possible to choose the chrominance order between * Cb is output first (Y0Cb, then Y1Cr, Y2Cb and so on). * Cr is output first (Y0Cr, then Y1Cb, Y2Cr and so on).

Signed-off-by: Yannick Fertre yannick.fertre@foss.st.com --- drivers/gpu/drm/stm/ltdc.c | 44 +++++++++++++++++++++++++++++++++++++- drivers/gpu/drm/stm/ltdc.h | 1 + 2 files changed, 44 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/stm/ltdc.c b/drivers/gpu/drm/stm/ltdc.c index 8dad3d00aa5c..b819f4cbcc3d 100644 --- a/drivers/gpu/drm/stm/ltdc.c +++ b/drivers/gpu/drm/stm/ltdc.c @@ -76,6 +76,7 @@ #define LTDC_LIPCR 0x0040 /* Line Interrupt Position Conf. */ #define LTDC_CPSR 0x0044 /* Current Position Status */ #define LTDC_CDSR 0x0048 /* Current Display Status */ +#define LTDC_EDCR 0x0060 /* External Display Control */ #define LTDC_FUT 0x0090 /* Fifo underrun Threshold */

/* Layer register offsets */ @@ -170,6 +171,10 @@ #define ISR_TERRIF BIT(2) /* Transfer ERRor Interrupt Flag */ #define ISR_RRIF BIT(3) /* Register Reload Interrupt Flag */

+#define EDCR_OCYEN BIT(25) /* Output Conversion to YCbCr 422: ENable */ +#define EDCR_OCYSEL BIT(26) /* Output Conversion to YCbCr 422: SELection of the CCIR */ +#define EDCR_OCYCO BIT(27) /* Output Conversion to YCbCr 422: Chrominance Order */ + #define LXCR_LEN BIT(0) /* Layer ENable */ #define LXCR_COLKEN BIT(1) /* Color Keying Enable */ #define LXCR_CLUTEN BIT(4) /* Color Look-Up Table ENable */ @@ -625,6 +630,7 @@ static void ltdc_crtc_mode_set_nofb(struct drm_crtc *crtc) struct drm_display_mode *mode = &crtc->state->adjusted_mode; u32 hsync, vsync, accum_hbp, accum_vbp, accum_act_w, accum_act_h; u32 total_width, total_height; + u32 bus_formats = MEDIA_BUS_FMT_RGB888_1X24; u32 bus_flags = 0; u32 val; int ret; @@ -650,8 +656,11 @@ static void ltdc_crtc_mode_set_nofb(struct drm_crtc *crtc)

if (bridge && bridge->timings) bus_flags = bridge->timings->input_bus_flags; - else if (connector) + else if (connector) { bus_flags = connector->display_info.bus_flags; + if (connector->display_info.num_bus_formats) + bus_formats = connector->display_info.bus_formats[0]; + }

if (!pm_runtime_active(ddev->dev)) { ret = pm_runtime_get_sync(ddev->dev); @@ -716,6 +725,36 @@ static void ltdc_crtc_mode_set_nofb(struct drm_crtc *crtc) regmap_update_bits(ldev->regmap, LTDC_TWCR, TWCR_TOTALH | TWCR_TOTALW, val);

regmap_write(ldev->regmap, LTDC_LIPCR, (accum_act_h + 1)); + + /* Configure the output format (hw version dependent) */ + if (ldev->caps.ycbcr_output) { + /* Input video dynamic_range & colorimetry */ + int vic = drm_match_cea_mode(mode); + u32 val; + + if (vic == 6 || vic == 7 || vic == 21 || vic == 22 || + vic == 2 || vic == 3 || vic == 17 || vic == 18) + /* ITU-R BT.601 */ + val = 0; + else + /* ITU-R BT.709 */ + val = EDCR_OCYSEL; + + switch (bus_formats) { + case MEDIA_BUS_FMT_YUYV8_1X16: + /* enable ycbcr output converter */ + regmap_write(ldev->regmap, LTDC_EDCR, EDCR_OCYEN | val); + break; + case MEDIA_BUS_FMT_YVYU8_1X16: + /* enable ycbcr output converter & invert chrominance order */ + regmap_write(ldev->regmap, LTDC_EDCR, EDCR_OCYEN | EDCR_OCYCO | val); + break; + default: + /* disable ycbcr output converter */ + regmap_write(ldev->regmap, LTDC_EDCR, 0); + break; + } + } }

static void ltdc_crtc_atomic_flush(struct drm_crtc *crtc, @@ -1267,6 +1306,7 @@ static int ltdc_get_caps(struct drm_device *ddev) if (ldev->caps.hw_version == HWVER_10200) ldev->caps.pad_max_freq_hz = 65000000; ldev->caps.nb_irq = 2; + ldev->caps.ycbcr_output = false; break; case HWVER_20101: ldev->caps.layer_ofs = LAY_OFS_0; @@ -1275,6 +1315,7 @@ static int ltdc_get_caps(struct drm_device *ddev) ldev->caps.non_alpha_only_l1 = false; ldev->caps.pad_max_freq_hz = 150000000; ldev->caps.nb_irq = 4; + ldev->caps.ycbcr_output = false; break; case HWVER_40100: ldev->caps.layer_ofs = LAY_OFS_1; @@ -1283,6 +1324,7 @@ static int ltdc_get_caps(struct drm_device *ddev) ldev->caps.non_alpha_only_l1 = false; ldev->caps.pad_max_freq_hz = 90000000; ldev->caps.nb_irq = 2; + ldev->caps.ycbcr_output = true; break; default: return -ENODEV; diff --git a/drivers/gpu/drm/stm/ltdc.h b/drivers/gpu/drm/stm/ltdc.h index 20b3dcc7817b..f04fcebb5223 100644 --- a/drivers/gpu/drm/stm/ltdc.h +++ b/drivers/gpu/drm/stm/ltdc.h @@ -21,6 +21,7 @@ struct ltdc_caps { bool non_alpha_only_l1; /* non-native no-alpha formats on layer 1 */ int pad_max_freq_hz; /* max frequency supported by pad */ int nb_irq; /* number of hardware interrupts */ + bool ycbcr_output; /* ycbcr output converter supported */ };

#define LTDC_MAX_LAYER 4