[PATCH v5 04/15] drm/edid: Use new encoded panel id style for quirks matching

From: Douglas Anderson
Date: Tue Sep 14 2021 - 16:22:34 EST


In the patch ("drm/edid: Allow the querying/working with the panel ID
from the EDID") we introduced a different way of working with the
panel ID stored in the EDID. Let's use this new way for the quirks
code.

Advantages of the new style:
* Smaller data structure size. Saves 4 bytes per panel.
* Iterate through quirks structure with just "==" instead of strncmp()
* In-kernel storage is more similar to what's stored in the EDID
itself making it easier to grok that they are referring to the same
value.

Signed-off-by: Douglas Anderson <dianders@xxxxxxxxxxxx>
Reviewed-by: Jani Nikula <jani.nikula@xxxxxxxxx>
---
This commit is only compile-tested. I don't have any DP panels that
exercise this code. Transition from the old table to the new one was
done with a regexp.

Changes in v5:
- Prettier encode panel ID function (thanks Andrzej!)

Changes in v4:
- ("Use new encoded panel id style for quirks matching") new for v4.

drivers/gpu/drm/drm_edid.c | 156 +++++++++++++++++--------------------
1 file changed, 70 insertions(+), 86 deletions(-)

diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c
index f84e0dd264f4..53b342c058be 100644
--- a/drivers/gpu/drm/drm_edid.c
+++ b/drivers/gpu/drm/drm_edid.c
@@ -100,122 +100,127 @@ struct detailed_mode_closure {
#define LEVEL_GTF2 2
#define LEVEL_CVT 3

+#define EDID_QUIRK(vend, product_id, _quirks) \
+{ \
+ .panel_id = drm_edid_encode_panel_id(vend, product_id), \
+ .quirks = _quirks \
+}
+
static const struct edid_quirk {
- char vendor[4];
- int product_id;
+ u32 panel_id;
u32 quirks;
} edid_quirk_list[] = {
/* Acer AL1706 */
- { "ACR", 44358, EDID_QUIRK_PREFER_LARGE_60 },
+ EDID_QUIRK("ACR", 44358, EDID_QUIRK_PREFER_LARGE_60),
/* Acer F51 */
- { "API", 0x7602, EDID_QUIRK_PREFER_LARGE_60 },
+ EDID_QUIRK("API", 0x7602, EDID_QUIRK_PREFER_LARGE_60),

/* AEO model 0 reports 8 bpc, but is a 6 bpc panel */
- { "AEO", 0, EDID_QUIRK_FORCE_6BPC },
+ EDID_QUIRK("AEO", 0, EDID_QUIRK_FORCE_6BPC),

/* BOE model on HP Pavilion 15-n233sl reports 8 bpc, but is a 6 bpc panel */
- { "BOE", 0x78b, EDID_QUIRK_FORCE_6BPC },
+ EDID_QUIRK("BOE", 0x78b, EDID_QUIRK_FORCE_6BPC),

/* CPT panel of Asus UX303LA reports 8 bpc, but is a 6 bpc panel */
- { "CPT", 0x17df, EDID_QUIRK_FORCE_6BPC },
+ EDID_QUIRK("CPT", 0x17df, EDID_QUIRK_FORCE_6BPC),

/* SDC panel of Lenovo B50-80 reports 8 bpc, but is a 6 bpc panel */
- { "SDC", 0x3652, EDID_QUIRK_FORCE_6BPC },
+ EDID_QUIRK("SDC", 0x3652, EDID_QUIRK_FORCE_6BPC),

/* BOE model 0x0771 reports 8 bpc, but is a 6 bpc panel */
- { "BOE", 0x0771, EDID_QUIRK_FORCE_6BPC },
+ EDID_QUIRK("BOE", 0x0771, EDID_QUIRK_FORCE_6BPC),

/* Belinea 10 15 55 */
- { "MAX", 1516, EDID_QUIRK_PREFER_LARGE_60 },
- { "MAX", 0x77e, EDID_QUIRK_PREFER_LARGE_60 },
+ EDID_QUIRK("MAX", 1516, EDID_QUIRK_PREFER_LARGE_60),
+ EDID_QUIRK("MAX", 0x77e, EDID_QUIRK_PREFER_LARGE_60),

/* Envision Peripherals, Inc. EN-7100e */
- { "EPI", 59264, EDID_QUIRK_135_CLOCK_TOO_HIGH },
+ EDID_QUIRK("EPI", 59264, EDID_QUIRK_135_CLOCK_TOO_HIGH),
/* Envision EN2028 */
- { "EPI", 8232, EDID_QUIRK_PREFER_LARGE_60 },
+ EDID_QUIRK("EPI", 8232, EDID_QUIRK_PREFER_LARGE_60),

/* Funai Electronics PM36B */
- { "FCM", 13600, EDID_QUIRK_PREFER_LARGE_75 |
- EDID_QUIRK_DETAILED_IN_CM },
+ EDID_QUIRK("FCM", 13600, EDID_QUIRK_PREFER_LARGE_75 |
+ EDID_QUIRK_DETAILED_IN_CM),

/* LGD panel of HP zBook 17 G2, eDP 10 bpc, but reports unknown bpc */
- { "LGD", 764, EDID_QUIRK_FORCE_10BPC },
+ EDID_QUIRK("LGD", 764, EDID_QUIRK_FORCE_10BPC),

/* LG Philips LCD LP154W01-A5 */
- { "LPL", 0, EDID_QUIRK_DETAILED_USE_MAXIMUM_SIZE },
- { "LPL", 0x2a00, EDID_QUIRK_DETAILED_USE_MAXIMUM_SIZE },
+ EDID_QUIRK("LPL", 0, EDID_QUIRK_DETAILED_USE_MAXIMUM_SIZE),
+ EDID_QUIRK("LPL", 0x2a00, EDID_QUIRK_DETAILED_USE_MAXIMUM_SIZE),

/* Samsung SyncMaster 205BW. Note: irony */
- { "SAM", 541, EDID_QUIRK_DETAILED_SYNC_PP },
+ EDID_QUIRK("SAM", 541, EDID_QUIRK_DETAILED_SYNC_PP),
/* Samsung SyncMaster 22[5-6]BW */
- { "SAM", 596, EDID_QUIRK_PREFER_LARGE_60 },
- { "SAM", 638, EDID_QUIRK_PREFER_LARGE_60 },
+ EDID_QUIRK("SAM", 596, EDID_QUIRK_PREFER_LARGE_60),
+ EDID_QUIRK("SAM", 638, EDID_QUIRK_PREFER_LARGE_60),

/* Sony PVM-2541A does up to 12 bpc, but only reports max 8 bpc */
- { "SNY", 0x2541, EDID_QUIRK_FORCE_12BPC },
+ EDID_QUIRK("SNY", 0x2541, EDID_QUIRK_FORCE_12BPC),

/* ViewSonic VA2026w */
- { "VSC", 5020, EDID_QUIRK_FORCE_REDUCED_BLANKING },
+ EDID_QUIRK("VSC", 5020, EDID_QUIRK_FORCE_REDUCED_BLANKING),

/* Medion MD 30217 PG */
- { "MED", 0x7b8, EDID_QUIRK_PREFER_LARGE_75 },
+ EDID_QUIRK("MED", 0x7b8, EDID_QUIRK_PREFER_LARGE_75),

/* Lenovo G50 */
- { "SDC", 18514, EDID_QUIRK_FORCE_6BPC },
+ EDID_QUIRK("SDC", 18514, EDID_QUIRK_FORCE_6BPC),

/* Panel in Samsung NP700G7A-S01PL notebook reports 6bpc */
- { "SEC", 0xd033, EDID_QUIRK_FORCE_8BPC },
+ EDID_QUIRK("SEC", 0xd033, EDID_QUIRK_FORCE_8BPC),

/* Rotel RSX-1058 forwards sink's EDID but only does HDMI 1.1*/
- { "ETR", 13896, EDID_QUIRK_FORCE_8BPC },
+ EDID_QUIRK("ETR", 13896, EDID_QUIRK_FORCE_8BPC),

/* Valve Index Headset */
- { "VLV", 0x91a8, EDID_QUIRK_NON_DESKTOP },
- { "VLV", 0x91b0, EDID_QUIRK_NON_DESKTOP },
- { "VLV", 0x91b1, EDID_QUIRK_NON_DESKTOP },
- { "VLV", 0x91b2, EDID_QUIRK_NON_DESKTOP },
- { "VLV", 0x91b3, EDID_QUIRK_NON_DESKTOP },
- { "VLV", 0x91b4, EDID_QUIRK_NON_DESKTOP },
- { "VLV", 0x91b5, EDID_QUIRK_NON_DESKTOP },
- { "VLV", 0x91b6, EDID_QUIRK_NON_DESKTOP },
- { "VLV", 0x91b7, EDID_QUIRK_NON_DESKTOP },
- { "VLV", 0x91b8, EDID_QUIRK_NON_DESKTOP },
- { "VLV", 0x91b9, EDID_QUIRK_NON_DESKTOP },
- { "VLV", 0x91ba, EDID_QUIRK_NON_DESKTOP },
- { "VLV", 0x91bb, EDID_QUIRK_NON_DESKTOP },
- { "VLV", 0x91bc, EDID_QUIRK_NON_DESKTOP },
- { "VLV", 0x91bd, EDID_QUIRK_NON_DESKTOP },
- { "VLV", 0x91be, EDID_QUIRK_NON_DESKTOP },
- { "VLV", 0x91bf, EDID_QUIRK_NON_DESKTOP },
+ EDID_QUIRK("VLV", 0x91a8, EDID_QUIRK_NON_DESKTOP),
+ EDID_QUIRK("VLV", 0x91b0, EDID_QUIRK_NON_DESKTOP),
+ EDID_QUIRK("VLV", 0x91b1, EDID_QUIRK_NON_DESKTOP),
+ EDID_QUIRK("VLV", 0x91b2, EDID_QUIRK_NON_DESKTOP),
+ EDID_QUIRK("VLV", 0x91b3, EDID_QUIRK_NON_DESKTOP),
+ EDID_QUIRK("VLV", 0x91b4, EDID_QUIRK_NON_DESKTOP),
+ EDID_QUIRK("VLV", 0x91b5, EDID_QUIRK_NON_DESKTOP),
+ EDID_QUIRK("VLV", 0x91b6, EDID_QUIRK_NON_DESKTOP),
+ EDID_QUIRK("VLV", 0x91b7, EDID_QUIRK_NON_DESKTOP),
+ EDID_QUIRK("VLV", 0x91b8, EDID_QUIRK_NON_DESKTOP),
+ EDID_QUIRK("VLV", 0x91b9, EDID_QUIRK_NON_DESKTOP),
+ EDID_QUIRK("VLV", 0x91ba, EDID_QUIRK_NON_DESKTOP),
+ EDID_QUIRK("VLV", 0x91bb, EDID_QUIRK_NON_DESKTOP),
+ EDID_QUIRK("VLV", 0x91bc, EDID_QUIRK_NON_DESKTOP),
+ EDID_QUIRK("VLV", 0x91bd, EDID_QUIRK_NON_DESKTOP),
+ EDID_QUIRK("VLV", 0x91be, EDID_QUIRK_NON_DESKTOP),
+ EDID_QUIRK("VLV", 0x91bf, EDID_QUIRK_NON_DESKTOP),

/* HTC Vive and Vive Pro VR Headsets */
- { "HVR", 0xaa01, EDID_QUIRK_NON_DESKTOP },
- { "HVR", 0xaa02, EDID_QUIRK_NON_DESKTOP },
+ EDID_QUIRK("HVR", 0xaa01, EDID_QUIRK_NON_DESKTOP),
+ EDID_QUIRK("HVR", 0xaa02, EDID_QUIRK_NON_DESKTOP),

/* Oculus Rift DK1, DK2, CV1 and Rift S VR Headsets */
- { "OVR", 0x0001, EDID_QUIRK_NON_DESKTOP },
- { "OVR", 0x0003, EDID_QUIRK_NON_DESKTOP },
- { "OVR", 0x0004, EDID_QUIRK_NON_DESKTOP },
- { "OVR", 0x0012, EDID_QUIRK_NON_DESKTOP },
+ EDID_QUIRK("OVR", 0x0001, EDID_QUIRK_NON_DESKTOP),
+ EDID_QUIRK("OVR", 0x0003, EDID_QUIRK_NON_DESKTOP),
+ EDID_QUIRK("OVR", 0x0004, EDID_QUIRK_NON_DESKTOP),
+ EDID_QUIRK("OVR", 0x0012, EDID_QUIRK_NON_DESKTOP),

/* Windows Mixed Reality Headsets */
- { "ACR", 0x7fce, EDID_QUIRK_NON_DESKTOP },
- { "HPN", 0x3515, EDID_QUIRK_NON_DESKTOP },
- { "LEN", 0x0408, EDID_QUIRK_NON_DESKTOP },
- { "LEN", 0xb800, EDID_QUIRK_NON_DESKTOP },
- { "FUJ", 0x1970, EDID_QUIRK_NON_DESKTOP },
- { "DEL", 0x7fce, EDID_QUIRK_NON_DESKTOP },
- { "SEC", 0x144a, EDID_QUIRK_NON_DESKTOP },
- { "AUS", 0xc102, EDID_QUIRK_NON_DESKTOP },
+ EDID_QUIRK("ACR", 0x7fce, EDID_QUIRK_NON_DESKTOP),
+ EDID_QUIRK("HPN", 0x3515, EDID_QUIRK_NON_DESKTOP),
+ EDID_QUIRK("LEN", 0x0408, EDID_QUIRK_NON_DESKTOP),
+ EDID_QUIRK("LEN", 0xb800, EDID_QUIRK_NON_DESKTOP),
+ EDID_QUIRK("FUJ", 0x1970, EDID_QUIRK_NON_DESKTOP),
+ EDID_QUIRK("DEL", 0x7fce, EDID_QUIRK_NON_DESKTOP),
+ EDID_QUIRK("SEC", 0x144a, EDID_QUIRK_NON_DESKTOP),
+ EDID_QUIRK("AUS", 0xc102, EDID_QUIRK_NON_DESKTOP),

/* Sony PlayStation VR Headset */
- { "SNY", 0x0704, EDID_QUIRK_NON_DESKTOP },
+ EDID_QUIRK("SNY", 0x0704, EDID_QUIRK_NON_DESKTOP),

/* Sensics VR Headsets */
- { "SEN", 0x1019, EDID_QUIRK_NON_DESKTOP },
+ EDID_QUIRK("SEN", 0x1019, EDID_QUIRK_NON_DESKTOP),

/* OSVR HDK and HDK2 VR Headsets */
- { "SVR", 0x1019, EDID_QUIRK_NON_DESKTOP },
+ EDID_QUIRK("SVR", 0x1019, EDID_QUIRK_NON_DESKTOP),
};

/*
@@ -2090,9 +2095,8 @@ EXPORT_SYMBOL(drm_get_edid);
static u32 edid_extract_panel_id(const struct edid *edid)
{
/*
- * In theory we could try to de-obfuscate this like edid_get_quirks()
- * does, but it's easier to just deal with a 32-bit number since then
- * it can be compared with "==".
+ * We represent the ID as a 32-bit number so it can easily be compared
+ * with "==".
*
* NOTE that we deal with endianness differently for the top half
* of this ID than for the bottom half. The bottom half (the product
@@ -2197,25 +2201,6 @@ EXPORT_SYMBOL(drm_edid_duplicate);

/*** EDID parsing ***/

-/**
- * edid_vendor - match a string against EDID's obfuscated vendor field
- * @edid: EDID to match
- * @vendor: vendor string
- *
- * Returns true if @vendor is in @edid, false otherwise
- */
-static bool edid_vendor(const struct edid *edid, const char *vendor)
-{
- char edid_vendor[3];
-
- edid_vendor[0] = ((edid->mfg_id[0] & 0x7c) >> 2) + '@';
- edid_vendor[1] = (((edid->mfg_id[0] & 0x3) << 3) |
- ((edid->mfg_id[1] & 0xe0) >> 5)) + '@';
- edid_vendor[2] = (edid->mfg_id[1] & 0x1f) + '@';
-
- return !strncmp(edid_vendor, vendor, 3);
-}
-
/**
* edid_get_quirks - return quirk flags for a given EDID
* @edid: EDID to process
@@ -2224,14 +2209,13 @@ static bool edid_vendor(const struct edid *edid, const char *vendor)
*/
static u32 edid_get_quirks(const struct edid *edid)
{
+ u32 panel_id = edid_extract_panel_id(edid);
const struct edid_quirk *quirk;
int i;

for (i = 0; i < ARRAY_SIZE(edid_quirk_list); i++) {
quirk = &edid_quirk_list[i];
-
- if (edid_vendor(edid, quirk->vendor) &&
- (EDID_PRODUCT_ID(edid) == quirk->product_id))
+ if (quirk->panel_id == panel_id)
return quirk->quirks;
}

--
2.33.0.309.g3052b89438-goog