[igt-dev] [v6 i-g-t 1/3] tests/kms_color_helper: Read deep-color capability from EDID
Petri Latvala
petri.latvala at intel.com
Fri Feb 18 09:49:11 UTC 2022
On Thu, Feb 17, 2022 at 09:24:56PM +0530, Bhanuprakash Modem wrote:
> Add a helper function to read the panel's deep-color capability
> from EDID.
>
> For EDID 1.3, we need to read deep color capability from Vendor
> Specific Data Block, and for EDID 1.4 read bit depth from Video
> Input Definition.
>
> Vendor Specific Data Block for "HDMI Licensing LLC":
> ---------------------------------------------------------
> | Byte| Bit | Description |
> ---------------------------------------------------------
> | | Bit 6 | 16-bit-per-channel deep color (48-bit)|
> | 6 | Bit 5 | 12-bit-per-channel deep color (36-bit)|
> | | Bit 4 | 10-bit-per-channel deep color (30-bit)|
> ---------------------------------------------------------
>
> Video Input Definition (1-byte):
> * Video Signal Interface: Bit 7 (1:Digital, 0:Analog)
> * Color Bit Depth: Bits 6 → 4
> -----------------------------------------------------
> | 7 | 6 5 4 | 3 2 1 0 | Color Bit Depth: Bits 6 → 4 |
> |---|-------|---------|-----------------------------|
> | 1 | 0 0 0 | x x x x | Color Bit Depth is undefined|
> | 1 | 0 0 1 | x x x x | 6 Bits per Primary Color |
> | 1 | 0 1 0 | x x x x | 8 Bits per Primary Color |
> | 1 | 0 1 1 | x x x x | 10 Bits per Primary Color |
> | 1 | 1 0 0 | x x x x | 12 Bits per Primary Color |
> | 1 | 1 0 1 | x x x x | 14 Bits per Primary Color |
> | 1 | 1 1 0 | x x x x | 16 Bits per Primary Color |
> | 1 | 1 1 1 | x x x x | Reserved (Do Not Use) |
> -----------------------------------------------------
> For deep-color we need atleast 10-bits.
>
> V2:
> * Add EDID 1.3 support
> V3:
> * Fix reading VSDB flags1 for deep-color
> V4:
> * Separate functions for EDID 1.3 & EDID 1.4
> * Other minor cleanups
> V5:
> * Fine tune the logic to identify DC support for RGB format
> V6:
> * Cleanup
>
> Cc: Uma Shankar <uma.shankar at intel.com>
> Signed-off-by: Bhanuprakash Modem <bhanuprakash.modem at intel.com>
> ---
> lib/igt_edid.c | 66 ++++++++++++++++++++++++++++++++++++++++
> lib/igt_edid.h | 2 ++
> tests/kms_color_helper.c | 52 +++++++++++++++++++++++++++++++
> tests/kms_color_helper.h | 3 ++
> 4 files changed, 123 insertions(+)
>
> diff --git a/lib/igt_edid.c b/lib/igt_edid.c
> index df346c4c8c..cb31a34b7b 100644
> --- a/lib/igt_edid.c
> +++ b/lib/igt_edid.c
> @@ -349,6 +349,72 @@ size_t edid_get_size(const struct edid *edid)
> edid->extensions_len * sizeof(struct edid_ext);
> }
>
> +static int ieee_oui(uint8_t oui[CEA_VSDB_HEADER_SIZE])
> +{
> + return (oui[2] << 16) | (oui[1] << 8) | oui[0];
> +}
> +
> +/**
> + * edid_get_deep_color_from_vsdb: return the Deep Color info from Vender
> + * Specific Data Block (VSDB), if VSDB not found then return zero.
> + */
> +uint8_t edid_get_deep_color_from_vsdb(const struct edid *edid)
> +{
> + const struct edid_ext *edid_ext;
> + const struct edid_cea *edid_cea;
> + const char *cea_data;
> + uint8_t deep_color = 0;
> + int offset, i, j;
> +
> + /* Read from vendor specific data block first, if vsdb not found
> + * return 0.
> + */
> + for (i = 0; i < edid->extensions_len; i++) {
> + edid_ext = &edid->extensions[i];
> + edid_cea = &edid_ext->data.cea;
> +
> + if ((edid_ext->tag != EDID_EXT_CEA) ||
> + (edid_cea->revision != 3))
> + continue;
> +
> + offset = edid_cea->dtd_start;
> + cea_data = edid_cea->data;
> +
> + for (j = 0; j < offset; j += (cea_data[j] & 0x1F) + 1) {
> + struct edid_cea_data_block *vsdb =
> + (struct edid_cea_data_block *)(cea_data + j);
> +
> + if (((vsdb->type_len & 0xE0) >> 5) != EDID_CEA_DATA_VENDOR_SPECIFIC)
> + continue;
> +
> + if (ieee_oui(vsdb->data.vsdbs->ieee_oui) == 0x000C03)
> + deep_color = vsdb->data.vsdbs->data.hdmi.flags1;
> +
> + if (deep_color & (7 << 4))
> + return deep_color;
> +
> + }
> + }
> +
> + return 0;
> +}
> +
> +/**
> + * edid_get_bit_depth: Read from the Video Input Definition and return the
> + * Color Bit Depth if Input is a Digital Video, else return zero.
> + */
> +uint8_t edid_get_bit_depth_from_vid(const struct edid *edid)
> +{
> + /*
> + * Video Signal Interface: Bit 7 (1:Digital, 0:Analog)
> + * Color Bit Depth: Bits 6 → 4
> + */
> + if (!(edid->input & (1 << 7)))
> + return 0;
> +
> + return ((edid->input & (7 << 4)) >> 4);
> +}
> +
> /**
> * cea_sad_init_pcm:
> * @channels: the number of supported channels (max. 8)
> diff --git a/lib/igt_edid.h b/lib/igt_edid.h
> index aac2f4a208..a9251d689e 100644
> --- a/lib/igt_edid.h
> +++ b/lib/igt_edid.h
> @@ -377,6 +377,8 @@ void edid_update_checksum(struct edid *edid);
> void base_edid_update_checksum(struct edid *edid);
> size_t edid_get_size(const struct edid *edid);
> void edid_get_mfg(const struct edid *edid, char out[static 3]);
> +uint8_t edid_get_deep_color_from_vsdb(const struct edid *edid);
> +uint8_t edid_get_bit_depth_from_vid(const struct edid *edid);
> void detailed_timing_set_mode(struct detailed_timing *dt, drmModeModeInfo *mode,
> int width_mm, int height_mm);
> void detailed_timing_set_monitor_range_mode(struct detailed_timing *dt,
> diff --git a/tests/kms_color_helper.c b/tests/kms_color_helper.c
> index d71e7bb2e6..6b3af02b00 100644
> --- a/tests/kms_color_helper.c
> +++ b/tests/kms_color_helper.c
> @@ -24,6 +24,58 @@
>
> #include "kms_color_helper.h"
>
> +bool
> +is_panel_supports_deep_color(int fd, drmModeConnector *connector)
> +{
> + uint64_t edid_blob_id;
> + uint8_t bit_depth, rev;
> + const struct edid *edid;
> + bool result;
> + drmModePropertyBlobPtr edid_blob = NULL;
> +
> + igt_assert(kmstest_get_property(fd, connector->connector_id,
> + DRM_MODE_OBJECT_CONNECTOR, "EDID", NULL,
> + &edid_blob_id, NULL));
> + edid_blob = drmModeGetPropertyBlob(fd, edid_blob_id);
> + igt_require_f(edid_blob, "EDID blob is NULL\n");
> +
> + edid = (const struct edid *) edid_blob->data;
> + rev = edid->revision;
> +
> + if (rev >= 4) {
> + bit_depth = edid_get_bit_depth_from_vid(edid);
> +
> + if (bit_depth > 0 && bit_depth < 7)
> + igt_info("Max supported bit depth: %d\n", ((bit_depth << 1) + 4));
> + else
> + igt_info("Max supported bit depth: Undefined\n");
> +
> + result = (bit_depth >= 3) && (bit_depth < 7);
> + } else {
> + bit_depth = edid_get_deep_color_from_vsdb(edid);
> +
> + if (bit_depth & HDMI_VSDB_DC_48BIT)
> + igt_info("Max supported bit depth: 16\n");
> + else if (bit_depth & HDMI_VSDB_DC_36BIT)
> + igt_info("Max supported bit depth: 12\n");
> + else if (bit_depth & HDMI_VSDB_DC_30BIT)
> + igt_info("Max supported bit depth: 10\n");
> + else
> + igt_info("Max supported bit depth: Undefined\n");
> +
> + result = !!(bit_depth & (7 << 4));
> + }
> + drmModeFreePropertyBlob(edid_blob);
> +
> + return result;
> +}
> +
> +bool is_max_bpc_supported(igt_output_t *output)
> +{
> + return igt_output_has_prop(output, IGT_CONNECTOR_MAX_BPC) &&
> + igt_output_get_prop(output, IGT_CONNECTOR_MAX_BPC);
> +}
> +
> void paint_gradient_rectangles(data_t *data,
> drmModeModeInfo *mode,
> color_t *colors,
> diff --git a/tests/kms_color_helper.h b/tests/kms_color_helper.h
> index bb6f0054f3..992087ac9c 100644
> --- a/tests/kms_color_helper.h
> +++ b/tests/kms_color_helper.h
> @@ -36,6 +36,7 @@
> #include "drm.h"
> #include "drmtest.h"
> #include "igt.h"
> +#include "igt_edid.h"
>
>
> /* Internal */
> @@ -64,6 +65,8 @@ typedef struct {
> color_t coeffs[];
> } gamma_lut_t;
>
> +bool is_panel_supports_deep_color(int fd, drmModeConnector *connector);
Double verb here, "is" + "supports". panel_supports_deep_color()
--
Petri Latvala
> +bool is_max_bpc_supported(igt_output_t *output);
> void paint_gradient_rectangles(data_t *data,
> drmModeModeInfo *mode,
> color_t *colors,
> --
> 2.35.0
>
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