edid: Add helper function to calculate bits-per-pixel dependent values

Coreboot and most payloads support three basic pixel widths for the
framebuffer. It assumes 32 by default, but several chipsets need to
override that value with whatever else they're supporting. Our struct
edid contains multiple convenience values that are directly derived from
this (and other properties), so changing the bits per pixel always
requires recalculating all those dependents in the chipset code. This
patch provides a small convenience wrapper that can be used to
consistently update the whole struct edid with a new pixel width
instead, so we no longer need to duplicate those calculations
everywhere.

BUG=None
TEST=Booted Oak in all three pixel widths (which it conveniently all
supports), confirmed that images looked good.

Change-Id: I5376dd4e28cf107ac2fba1dc418f5e1c5a2e2de6
Signed-off-by: Julius Werner <jwerner@chromium.org>
Reviewed-on: https://review.coreboot.org/14158
Tested-by: build bot (Jenkins)
Reviewed-by: Patrick Georgi <pgeorgi@google.com>

4 files changed, 16 insertions, 23 deletions

diff --git a/src/soc/nvidia/tegra124/display.c b/src/soc/nvidia/tegra124/display.c
index ac1b950b0b..74202bad23 100644
--- a/src/soc/nvidia/tegra124/display.c
+++ b/src/soc/nvidia/tegra124/display.c
@@ -331,10 +331,9 @@ void display_startup(device_t dev)
 	/* tell depthcharge ...
 	 */
 	struct edid edid;
-	edid.bytes_per_line = ((config->xres * config->framebuffer_bits_per_pixel / 8 + 31) /
-				32 * 32);
-	edid.x_resolution = edid.bytes_per_line / (config->framebuffer_bits_per_pixel / 8);
-	edid.y_resolution = config->yres;
-	edid.framebuffer_bits_per_pixel = config->framebuffer_bits_per_pixel;
+	edid.mode.va = config->yres;
+	edid.mode.ha = config->xres;
+	edid_set_framebuffer_bits_per_pixel(&edid,
+					    config->framebuffer_bits_per_pixel);
 	set_vbe_mode_info_valid(&edid, (uintptr_t)(framebuffer_base_mb*MiB));
 }
diff --git a/src/soc/nvidia/tegra132/dc.c b/src/soc/nvidia/tegra132/dc.c
index 2b1687b631..562061a1d3 100644
--- a/src/soc/nvidia/tegra132/dc.c
+++ b/src/soc/nvidia/tegra132/dc.c
@@ -226,13 +226,11 @@ void pass_mode_info_to_payload(
 			struct soc_nvidia_tegra132_config *config)
 {
 	struct edid edid;
-	/* Align bytes_per_line to 64 bytes as required by dc */
-	edid.bytes_per_line = ALIGN_UP((config->display_xres *
-				config->framebuffer_bits_per_pixel / 8), 64);
-	edid.x_resolution = edid.bytes_per_line /
-				(config->framebuffer_bits_per_pixel / 8);
-	edid.y_resolution = config->display_yres;
-	edid.framebuffer_bits_per_pixel = config->framebuffer_bits_per_pixel;
+
+	edid.mode.va = config->display_yres;
+	edid.mode.ha = config->display_xres;
+	edid_set_framebuffer_bits_per_pixel(&edid,
+					    config->framebuffer_bits_per_pixel);
 
 	printk(BIOS_INFO, "%s: bytes_per_line: %d, bits_per_pixel: %d\n "
 			"               x_res x y_res: %d x %d, size: %d\n",
diff --git a/src/soc/nvidia/tegra210/dc.c b/src/soc/nvidia/tegra210/dc.c
index 5dad92e6b8..72f1bcb3fa 100644
--- a/src/soc/nvidia/tegra210/dc.c
+++ b/src/soc/nvidia/tegra210/dc.c
@@ -226,13 +226,11 @@ void pass_mode_info_to_payload(
 			struct soc_nvidia_tegra210_config *config)
 {
 	struct edid edid;
-	/* Align bytes_per_line to 64 bytes as required by dc */
-	edid.bytes_per_line = ALIGN_UP((config->display_xres *
-				config->framebuffer_bits_per_pixel / 8), 64);
-	edid.x_resolution = edid.bytes_per_line /
-				(config->framebuffer_bits_per_pixel / 8);
-	edid.y_resolution = config->display_yres;
-	edid.framebuffer_bits_per_pixel = config->framebuffer_bits_per_pixel;
+
+	edid.mode.va = config->display_yres;
+	edid.mode.ha = config->display_xres;
+	edid_set_framebuffer_bits_per_pixel(&edid,
+					    config->framebuffer_bits_per_pixel);
 
 	printk(BIOS_INFO, "%s: bytes_per_line: %d, bits_per_pixel: %d\n "
 			"               x_res x y_res: %d x %d, size: %d\n",
diff --git a/src/soc/rockchip/rk3288/display.c b/src/soc/rockchip/rk3288/display.c
index 56eea076f8..66b2edc5b8 100644
--- a/src/soc/rockchip/rk3288/display.c
+++ b/src/soc/rockchip/rk3288/display.c
@@ -94,10 +94,8 @@ void rk_display_init(device_t dev, u32 lcdbase,
 		return;
 	}
 
-	edid.framebuffer_bits_per_pixel = conf->framebuffer_bits_per_pixel;
-	edid.bytes_per_line = edid.mode.ha * conf->framebuffer_bits_per_pixel / 8;
-	edid.x_resolution = edid.mode.ha;
-	edid.y_resolution = edid.mode.va;
+	edid_set_framebuffer_bits_per_pixel(&edid,
+					    conf->framebuffer_bits_per_pixel);
 	rkvop_mode_set(conf->vop_id, &edid, detected_mode);
 
 	rkvop_enable(conf->vop_id, lcdbase, &edid);