13575 loader: use display pixel density for font autoselection

Reviewed by: Yuri Pankov <yuripv@yuripv.dev>
Approved by: Robert Mustacchi <rm@fingolfin.org>

5 files changed, 127 insertions, 11 deletions

diff --git a/usr/src/boot/Makefile.version b/usr/src/boot/Makefile.version
index 486e265893..656a8a3d08 100644
--- a/usr/src/boot/Makefile.version
+++ b/usr/src/boot/Makefile.version
@@ -34,4 +34,4 @@ LOADER_VERSION = 1.1
 # Use date like formatting here, YYYY.MM.DD.XX, without leading zeroes.
 # The version is processed from left to right, the version number can only
 # be increased.
-BOOT_VERSION = $(LOADER_VERSION)-2021.03.12.1
+BOOT_VERSION = $(LOADER_VERSION)-2021.03.16.1
diff --git a/usr/src/boot/sys/boot/common/gfx_fb.c b/usr/src/boot/sys/boot/common/gfx_fb.c
index 6331a28ab7..09875a85f1 100644
--- a/usr/src/boot/sys/boot/common/gfx_fb.c
+++ b/usr/src/boot/sys/boot/common/gfx_fb.c
@@ -1727,6 +1727,113 @@ gfx_fb_putimage(png_t *png, uint32_t ux1, uint32_t uy1, uint32_t ux2,
 	return (0);
 }
 
+/* Return  w^2 + h^2 or 0, if the dimensions are unknown */
+static unsigned
+edid_diagonal_squared(void)
+{
+	unsigned w, h;
+
+	if (edid_info == NULL)
+		return (0);
+
+	w = edid_info->display.max_horizontal_image_size;
+	h = edid_info->display.max_vertical_image_size;
+
+	/* If either one is 0, we have aspect ratio, not size */
+	if (w == 0 || h == 0)
+		return (0);
+
+	/*
+	 * some monitors encode the aspect ratio instead of the physical size.
+	 */
+	if ((w == 16 && h == 9) || (w == 16 && h == 10) ||
+	    (w == 4 && h == 3) || (w == 5 && h == 4))
+		return (0);
+
+	/*
+	 * translate cm to inch, note we scale by 100 here.
+	 */
+	w = w * 100 / 254;
+	h = h * 100 / 254;
+
+	/* Return w^2 + h^2 */
+	return (w * w + h * h);
+}
+
+/*
+ * calculate pixels per inch.
+ */
+static unsigned
+gfx_get_ppi(void)
+{
+	unsigned dp, di;
+
+	di = edid_diagonal_squared();
+	if (di == 0)
+		return (0);
+
+	dp = gfx_fb.framebuffer_common.framebuffer_width *
+	    gfx_fb.framebuffer_common.framebuffer_width +
+	    gfx_fb.framebuffer_common.framebuffer_height *
+	    gfx_fb.framebuffer_common.framebuffer_height;
+
+	return (isqrt(dp / di));
+}
+
+/*
+ * Calculate font size from density independent pixels (dp):
+ * ((16dp * ppi) / 160) * display_factor.
+ * Here we are using fixed constants: 1dp == 160 ppi and
+ * display_factor 2.
+ *
+ * We are rounding font size up and are searching for font which is
+ * not smaller than calculated size value.
+ */
+bitmap_data_t *
+gfx_get_font(void)
+{
+	unsigned ppi, size;
+	bitmap_data_t *font = NULL;
+	struct fontlist *fl, *next;
+
+	/* Text mode is not supported here. */
+	if (gfx_fb.framebuffer_common.framebuffer_type ==
+	    MULTIBOOT_FRAMEBUFFER_TYPE_EGA_TEXT)
+		return (NULL);
+
+	ppi = gfx_get_ppi();
+	if (ppi == 0)
+		return (NULL);
+
+	/*
+	 * We will search for 16dp font.
+	 * We are using scale up by 10 for roundup.
+	 */
+	size = (16 * ppi * 10) / 160;
+	/* Apply display factor 2.  */
+	size = roundup(size * 2, 10) / 10;
+
+	STAILQ_FOREACH(fl, &fonts, font_next) {
+		next = STAILQ_NEXT(fl, font_next);
+		/*
+		 * If this is last font or, if next font is smaller,
+		 * we have our font. Make sure, it actually is loaded.
+		 */
+		if (next == NULL || next->font_data->height < size) {
+			font = fl->font_data;
+			if (font->font == NULL ||
+			    fl->font_flags == FONT_RELOAD) {
+				if (fl->font_load != NULL &&
+				    fl->font_name != NULL)
+					font = fl->font_load(fl->font_name);
+			}
+			break;
+		}
+	}
+
+	return (font);
+}
+
 static int
 load_mapping(int fd, struct font *fp, int n)
 {
diff --git a/usr/src/boot/sys/boot/common/gfx_fb.h b/usr/src/boot/sys/boot/common/gfx_fb.h
index 3fb7fcc3af..8d20dcf162 100644
--- a/usr/src/boot/sys/boot/common/gfx_fb.h
+++ b/usr/src/boot/sys/boot/common/gfx_fb.h
@@ -95,6 +95,8 @@ struct vesa_edid_info {
 	uint8_t checksum;
 } __packed;
 
+extern struct vesa_edid_info *edid_info;
+
 #define	STD_TIMINGS	8
 #define	DET_TIMINGS	4
 
diff --git a/usr/src/boot/sys/boot/efi/loader/framebuffer.c b/usr/src/boot/sys/boot/efi/loader/framebuffer.c
index 799678b222..bd86ea3e43 100644
--- a/usr/src/boot/sys/boot/efi/loader/framebuffer.c
+++ b/usr/src/boot/sys/boot/efi/loader/framebuffer.c
@@ -58,7 +58,7 @@ static EFI_HANDLE gop_handle;
 /* Saved initial GOP mode. */
 static uint32_t default_mode = UINT32_MAX;
 /* Cached EDID. */
-static struct vesa_edid_info *edid_info = NULL;
+struct vesa_edid_info *edid_info = NULL;
 
 static uint32_t gop_default_mode(void);
 static int efifb_set_mode(EFI_GRAPHICS_OUTPUT *, uint_t);
diff --git a/usr/src/boot/sys/boot/i386/libi386/vbe.c b/usr/src/boot/sys/boot/i386/libi386/vbe.c
index c48427f5f4..a0514aebec 100644
--- a/usr/src/boot/sys/boot/i386/libi386/vbe.c
+++ b/usr/src/boot/sys/boot/i386/libi386/vbe.c
@@ -49,6 +49,7 @@ static struct modeinfoblock *vbe_mode =
 	(struct modeinfoblock *)&vbestate.vbe_mode_info;
 static uint16_t *vbe_mode_list;
 static size_t vbe_mode_list_size;
+struct vesa_edid_info *edid_info = NULL;
 multiboot_color_t *cmap;
 /* The default VGA color palette format is 6 bits per primary color. */
 int palette_format = 6;
@@ -573,34 +574,40 @@ vbe_dump_mode(int modenum, struct modeinfoblock *mi)
 static bool
 vbe_get_edid(edid_res_list_t *res)
 {
-	struct vesa_edid_info *edid_info;
+	struct vesa_edid_info *edidp;
 	const uint8_t magic[] = EDID_MAGIC;
 	int ddc_caps;
 	bool ret = false;
 
+	if (edid_info != NULL)
+		return (gfx_get_edid_resolution(edid_info, res));
+
 	ddc_caps = biosvbe_ddc_caps();
 	if (ddc_caps == 0) {
 		return (ret);
 	}
 
-	edid_info = bio_alloc(sizeof (*edid_info));
-	if (edid_info == NULL)
+	edidp = bio_alloc(sizeof (*edidp));
+	if (edidp == NULL)
 		return (ret);
-	memset(edid_info, 0, sizeof (*edid_info));
+	memset(edidp, 0, sizeof (*edidp));
 
-	if (VBE_ERROR(biosvbe_ddc_read_edid(0, edid_info)))
+	if (VBE_ERROR(biosvbe_ddc_read_edid(0, edidp)))
 		goto done;
 
-	if (memcmp(edid_info, magic, sizeof (magic)) != 0)
+	if (memcmp(edidp, magic, sizeof (magic)) != 0)
 		goto done;
 
 	/* Unknown EDID version. */
-	if (edid_info->header.version != 1)
+	if (edidp->header.version != 1)
 		goto done;
 
-	ret = gfx_get_edid_resolution(edid_info, res);
+	ret = gfx_get_edid_resolution(edidp, res);
+	edid_info = malloc(sizeof (*edid_info));
+	if (edid_info != NULL)
+		memcpy(edid_info, edidp, sizeof (*edid_info));
 done:
-	bio_free(edid_info, sizeof (*edid_info));
+	bio_free(edidp, sizeof (*edidp));
 	return (ret);
 }