[PATCH v5 4/6] drm/log: Color the timestamp, to improve readability

[Jocelyn Falempe]

Color the timesamp prefix, similar to dmesg.

Signed-off-by: Jocelyn Falempe <jfale...@redhat.com>
---
 drivers/gpu/drm/drm_log.c | 27 +++++++++++++++++++++------
 1 file changed, 21 insertions(+), 6 deletions(-)

diff --git a/drivers/gpu/drm/drm_log.c b/drivers/gpu/drm/drm_log.c
index 226e206e8b6a3..635dff7b37ce5 100644
--- a/drivers/gpu/drm/drm_log.c
+++ b/drivers/gpu/drm/drm_log.c
@@ -42,6 +42,7 @@ struct drm_log_scanout {
        u32 format;
        u32 px_width;
        u32 front_color;
+       u32 prefix_color;
 };
 
 struct drm_log {
@@ -97,7 +98,7 @@ static void drm_log_clear_line(struct drm_log_scanout 
*scanout, u32 line)
 }
 
 static void drm_log_draw_line(struct drm_log_scanout *scanout, const char *s,
-                             unsigned int len)
+                             unsigned int len, unsigned int prefix_len)
 {
        struct drm_framebuffer *fb = scanout->buffer->fb;
        struct iosys_map map;
@@ -114,9 +115,10 @@ static void drm_log_draw_line(struct drm_log_scanout 
*scanout, const char *s,
 
        iosys_map_incr(&map, r.y1 * fb->pitches[0]);
        for (i = 0; i < len && i < scanout->columns; i++) {
+               u32 color = (i < prefix_len) ? scanout->prefix_color : 
scanout->front_color;
                src = drm_draw_get_char_bitmap(font, s[i], font_pitch);
                drm_log_blit(&map, fb->pitches[0], src, font_pitch, 
font->height, font->width,
-                            1, px_width, scanout->front_color);
+                            1, px_width, color);
                iosys_map_incr(&map, font->width * px_width);
        }
 
@@ -128,7 +130,7 @@ static void drm_log_draw_line(struct drm_log_scanout 
*scanout, const char *s,
 }
 
 static void drm_log_draw_new_line(struct drm_log_scanout *scanout,
-                                 const char *s, unsigned int len)
+                                 const char *s, unsigned int len, unsigned int 
prefix_len)
 {
        if (scanout->line == 0) {
                drm_log_clear_line(scanout, 0);
@@ -137,23 +139,35 @@ static void drm_log_draw_new_line(struct drm_log_scanout 
*scanout,
        } else if (scanout->line + 2 < scanout->rows)
                drm_log_clear_line(scanout, scanout->line + 2);
 
-       drm_log_draw_line(scanout, s, len);
+       drm_log_draw_line(scanout, s, len, prefix_len);
 }
 
+/*
+ * Depends on print_time() in printk.c
+ * Timestamp is written with "[%5lu.%06lu]"
+ */
+#define TS_PREFIX_LEN 13
+
 static void drm_log_draw_kmsg_record(struct drm_log_scanout *scanout,
                                     const char *s, unsigned int len)
 {
+       u32 prefix_len = 0;
+
+       if (len > TS_PREFIX_LEN && s[0] == '[' && s[6] == '.' && 
s[TS_PREFIX_LEN] == ']')
+               prefix_len = TS_PREFIX_LEN + 1;
+
        /* do not print the ending \n character */
        if (s[len - 1] == '\n')
                len--;
 
        while (len > scanout->columns) {
-               drm_log_draw_new_line(scanout, s, scanout->columns);
+               drm_log_draw_new_line(scanout, s, scanout->columns, prefix_len);
                s += scanout->columns;
                len -= scanout->columns;
+               prefix_len = 0;
        }
        if (len)
-               drm_log_draw_new_line(scanout, s, len);
+               drm_log_draw_new_line(scanout, s, len, prefix_len);
 }
 
 static u32 drm_log_find_usable_format(struct drm_plane *plane)
@@ -193,6 +207,7 @@ static int drm_log_setup_modeset(struct drm_client_dev 
*client,
        scanout->rows = height / scanout->font->height;
        scanout->columns = width / scanout->font->width;
        scanout->front_color = drm_draw_color_from_xrgb8888(0xffffff, format);
+       scanout->prefix_color = drm_draw_color_from_xrgb8888(0x4e9a06, format);
        return 0;
 }
 
-- 
2.47.0