diff options
Diffstat (limited to 'drivers/video')
| -rw-r--r-- | drivers/video/Kconfig | 12 | ||||
| -rw-r--r-- | drivers/video/video-uclass.c | 54 |
2 files changed, 66 insertions, 0 deletions
diff --git a/drivers/video/Kconfig b/drivers/video/Kconfig index 0cf13adc7d..366e9ab465 100644 --- a/drivers/video/Kconfig +++ b/drivers/video/Kconfig @@ -22,6 +22,18 @@ config BACKLIGHT This provides backlight uclass driver that enables basic panel backlight support. +config VIDEO_COPY + bool "Enable copying the frame buffer to a hardware copy" + depends on DM_VIDEO + help + On some machines (e.g. x86), reading from the frame buffer is very + slow because it is uncached. To improve performance, this feature + allows the frame buffer to be kept in cached memory (allocated by + U-Boot) and then copied to the hardware frame-buffer as needed. + + To use this, your video driver must set @copy_base in + struct video_uc_platdata. + config BACKLIGHT_PWM bool "Generic PWM based Backlight Driver" depends on BACKLIGHT && DM_PWM diff --git a/drivers/video/video-uclass.c b/drivers/video/video-uclass.c index 1f2874554a..341db68e38 100644 --- a/drivers/video/video-uclass.c +++ b/drivers/video/video-uclass.c @@ -4,6 +4,7 @@ */ #include <common.h> +#include <console.h> #include <cpu_func.h> #include <dm.h> #include <log.h> @@ -201,6 +202,59 @@ int video_get_ysize(struct udevice *dev) return priv->ysize; } +#ifdef CONFIG_VIDEO_COPY +int video_sync_copy(struct udevice *dev, void *from, void *to) +{ + struct video_priv *priv = dev_get_uclass_priv(dev); + + if (priv->copy_fb) { + long offset, size; + + /* Find the offset of the first byte to copy */ + if ((ulong)to > (ulong)from) { + size = to - from; + offset = from - priv->fb; + } else { + size = from - to; + offset = to - priv->fb; + } + + /* + * Allow a bit of leeway for valid requests somewhere near the + * frame buffer + */ + if (offset < -priv->fb_size || offset > 2 * priv->fb_size) { +#ifdef DEBUG + char str[80]; + + snprintf(str, sizeof(str), + "[sync_copy fb=%p, from=%p, to=%p, offset=%lx]", + priv->fb, from, to, offset); + console_puts_select_stderr(true, str); +#endif + return -EFAULT; + } + + /* + * Silently crop the memcpy. This allows callers to avoid doing + * this themselves. It is common for the end pointer to go a + * few lines after the end of the frame buffer, since most of + * the update algorithms terminate a line after their last write + */ + if (offset + size > priv->fb_size) { + size = priv->fb_size - offset; + } else if (offset < 0) { + size += offset; + offset = 0; + } + + memcpy(priv->copy_fb + offset, priv->fb + offset, size); + } + + return 0; +} +#endif + /* Set up the colour map */ static int video_pre_probe(struct udevice *dev) { |