[U-Boot] [PATCH v4 15/16] lcd: Add CONSOLE_SCROLL_LINES option to speed console

[Lucas Stach]

Am Donnerstag, den 27.09.2012, 17:44 -0700 schrieb Simon Glass:
> When the cursor position gets to the end of the LCD console we normally
> scroll by one line. This adds an option to increase that value.
> 
> Console scrolling is often slow, and if a large amount of output is
> being sent, increasing this option to 10 or so will speed things up
> considerably.
> 
> Signed-off-by: Simon Glass <sjg at chromium.org>
> ---
> Changes in v3:
> - Fix tiny bug in mult-line lcd scrolling
> 
> Changes in v4:
> - Use CONFIG_CONSOLE_SCROLL_LINES instead of CONSOLE_SCROLL_LINES
> - Put default CONFIG_CONSOLE_SCROLL_LINES at top of file
> 
>  README       |    6 ++++++
>  common/lcd.c |   18 +++++++++++++++---
>  2 files changed, 21 insertions(+), 3 deletions(-)
> 
> diff --git a/README b/README
> index 1d0ce50..14b1f83 100644
> --- a/README
> +++ b/README
> @@ -1449,6 +1449,12 @@ The following options need to be configured:
>  		here, since it is cheaper to change data cache settings on
>  		a per-section basis.
>  
> +		CONFIG_CONSOLE_SCROLL_LINES
> +
> +		When the console need to be scrolled, this is the number of
> +		lines to scroll by. It defaults to 1. Increasing this makes
> +		the console jump but can help speed up operation when scrolling
> +		is slow.
>  
>  - Splash Screen Support: CONFIG_SPLASH_SCREEN
>  
> diff --git a/common/lcd.c b/common/lcd.c
> index 74fa3f9..460f0ca 100644
> --- a/common/lcd.c
> +++ b/common/lcd.c
> @@ -76,6 +76,11 @@
>  #define CONFIG_LCD_ALIGNMENT PAGE_SIZE
>  #endif
>  
> +/* By default we scroll by a single line */
> +#ifndef CONFIG_CONSOLE_SCROLL_LINES
> +#define CONFIG_CONSOLE_SCROLL_LINES 1
> +#endif
> +
>  DECLARE_GLOBAL_DATA_PTR;
>  
>  ulong lcd_setmem (ulong addr);
> @@ -131,12 +136,20 @@ void lcd_set_flush_dcache(int flush)
>  
>  static void console_scrollup(void)
>  {
> +	const int rows = CONFIG_CONSOLE_SCROLL_LINES;
> +
>  	/* Copy up rows ignoring the first one */
Comment is inaccurate as you possibly ignore more than the first line.

> -	memcpy(CONSOLE_ROW_FIRST, CONSOLE_ROW_SECOND, CONSOLE_SCROLL_SIZE);
> +	memcpy(CONSOLE_ROW_FIRST,
> +	       lcd_console_address + CONSOLE_ROW_SIZE * rows,
> +	       CONSOLE_SIZE - CONSOLE_ROW_SIZE * rows);
>  
>  	/* Clear the last one */
Same as above.

> -	memset(CONSOLE_ROW_LAST, COLOR_MASK(lcd_color_bg), CONSOLE_ROW_SIZE);
> +	memset(lcd_console_address + CONSOLE_SIZE - CONSOLE_ROW_SIZE * rows,
> +		COLOR_MASK(lcd_color_bg),
> +	       CONSOLE_ROW_SIZE * rows);
> +
>  	lcd_sync();
> +	console_row -= rows;
>  }
>  
>  /*----------------------------------------------------------------------*/
> @@ -165,7 +178,6 @@ static inline void console_newline(void)
>  	if (console_row >= CONSOLE_ROWS) {
>  		/* Scroll everything up */
>  		console_scrollup();
> -		--console_row;
>  	} else {
>  		lcd_sync();
>  	}