From a8552c7c9b53d1d4f36b95f2c80812d8a7bb4fff Mon Sep 17 00:00:00 2001 From: Hans de Goede Date: Tue, 5 May 2015 13:13:36 +0200 Subject: console: Fix pre-console flushing via cfb_console being very slow On my A10 OlinuxIno Lime I noticed a huge (5+ seconds) delay coming from console_init_r. This turns out to be caused by the preconsole buffer flushing to the cfb_console. The Lime only has a 16 bit memory bus and that is already heavy used to scan out the 1920x1080 framebuffer. The problem is that print_pre_console_buffer() was printing the buffer once character at a time and the cfb_console code then ends up doing a cache-flush for touched display lines for each character. This commit fixes this by first building a 0 terminated buffer and then printing it in one puts() call, avoiding unnecessary cache flushes. This changes the time for the flush from 5+ seconds to not noticable. The downside of this approach is that the pre-console buffer needs to fit on the stack, this is not that much to ask since we are talking about plain text here. This commit also adjusts the sunxi CONFIG_PRE_CON_BUF_SZ to actually fit on the stack. Sunxi currently is the only user of the pre-console code so no other boards need to be adjusted. Signed-off-by: Hans de Goede Reviewed-by: Tom Rini --- include/configs/sunxi-common.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include/configs/sunxi-common.h') diff --git a/include/configs/sunxi-common.h b/include/configs/sunxi-common.h index 723067ea74..0495dc3b8c 100644 --- a/include/configs/sunxi-common.h +++ b/include/configs/sunxi-common.h @@ -336,7 +336,7 @@ extern int soft_i2c_gpio_scl; /* Enable pre-console buffer to get complete log on the VGA console */ #define CONFIG_PRE_CONSOLE_BUFFER -#define CONFIG_PRE_CON_BUF_SZ (1024 * 1024) +#define CONFIG_PRE_CON_BUF_SZ 4096 /* Aprox 2 80*25 screens */ /* Use the room between the end of bootm_size and the framebuffer */ #define CONFIG_PRE_CON_BUF_ADDR 0x4f000000 -- cgit v1.2.3