Hi Nikhil,
On Fri, 17 Mar 2023 at 02:13, Nikhil M Jain n-jain1@ti.com wrote:
Hi Simon,
On 16/03/23 10:10, Nikhil M Jain wrote:
Hi Simon,
On 15/03/23 19:38, Simon Glass wrote:
Hi Nikhil,
On Wed, 15 Mar 2023 at 00:07, Nikhil M Jain n-jain1@ti.com wrote:
Hi Simon,
On 15/03/23 03:38, Simon Glass wrote:
Hi Nikhil,
On Mon, 13 Mar 2023 at 04:15, Nikhil M Jain n-jain1@ti.com wrote:
To enable splash screen at SPL stage move video driver and splash screen framework at SPL, which will bring up image on display very quickly and thus have early display support in SPL.
Nikhil M Jain (9): drivers: video: Kconfig: Necessary configs for video at SPL drivers: video: tidss: Kconfig: Configs to enable TIDSS at SPL cmd: Kconfig: Add necessary configs for splash screen at SPL drivers: video: Makefile: Compile video driver files at SPL drivers: video: tidss: Makefile: Add condition to compile TIDSS at SPL cmd: Makefile: Add rules to build bmp.c and read.c at SPL common: splash: Enable splash_display at SPL stage drivers: video: video-uclass: Disable u-boot logo at SPL board: ti: am62x: evm: OSPI support for splash screen
board/ti/am62x/evm.c | 6 ++++++ cmd/Kconfig | 17 +++++++++++++++++ cmd/Makefile | 2 ++ common/splash.c | 2 +- drivers/video/Kconfig | 32 ++++++++++++++++++++++++++++---- drivers/video/Makefile | 6 ++++++ drivers/video/tidss/Kconfig | 6 ++++++ drivers/video/tidss/Makefile | 1 + drivers/video/video-uclass.c | 2 +- include/splash.h | 2 +- 10 files changed, 69 insertions(+), 7 deletions(-)
I'm not necessarily arguing against this, but what is the need for this? How many milliseconds earlier does the image appear with this patch? What is the bottleneck? We should be able to get to U-Boot proper very quickly.
There is a significant difference in time, by adding support in SPL splash screen comes up by approx 650ms and at u-boot proper it comes at 2.6s, measured from first print in console as seen on AM62x. Also we plan to skip u-boot proper and load kernel directly.
Yes that really is terrible. It should be under a second for U-Boot proper!
Have you tried using bootstage to report the numbers?
No I haven't used the bootstage, I will use it to get the numbers.
Boot stage logs link: https://gist.github.com/NikMJain/beb60fe42b1e89829cdd5b8713284330
Have you tried using tracing to figure out what is wrong? Is it just slow storage?
U-boot proper comes up in one sec but the splash display is called through stdio_add_devices which is late in the board_init_r sequence defined in board_r.c.
Regards,
Simon
Thanks
On AM62x we have multi-stage boot first R5 SPL comes up then A53 SPL and u-boot proper, due to which splash screen at u-boot proper takes over 2 sec. On AM62x we have an aggressive requirement for an early splash screen. Hence we are moving splash screen support to SPL., which will bring splash screen time to approx 600 ms.
We also want to support falcon boot mode from A53 SPL, we have customers who don't want u-boot proper in production boot flow and still require splash screen, the only way to support it is to add splash screen at SPL.
u-boot logs with splash screen timings, measurement through timer_get_boot_us at u-boot proper and SPL. link: https://gist.github.com/NikMJain/3be0b6c92092678b6aec8e5fdbc46a98
I think it would be worth looking at what is taking so long. Could you add bootstage in there (which supports SPL as well) and produce a final report? Is BL31 taking a while?You can use bootstage_start()/bootstage_accum() to collect time on MMC loading, etc. even if you don't want to enable CONFIG_TRACE.
This is an important area that will affect a lot of boards. If it takes 2 seconds to get into U-Boot, everyone is going to want to avoid it.
Regards, Simon