Hi Lin, On 26 October 2015 at 18:27, hl <h...@rock-chips.com> wrote: > Hi Simon, > > > On 26/10/15 12:12, Simon Glass wrote: > > Hi, > > On Oct 22, 2015 7:22 PM, "hl" <h...@rock-chips.com> wrote: >> >> Hi Simon, >> >> >> On 23/10/15 09:04, Simon Glass wrote: >>> >>> Hi Eddie, >>> >>> On 22 October 2015 at 18:54, Eddie Cai <eddie....@rock-chips.com> wrote: >>>> >>>> Hi Simon >>>> >>>> 2015-10-23 0:30 GMT+08:00 Simon Glass <s...@chromium.org>: >>>>> >>>>> Hi Eddie, >>>>> >>>>> On 22 October 2015 at 10:01, Eddie Cai <eddie....@rock-chips.com> >>>>> wrote: >>>>>> >>>>>> Hi Simon >>>>>> >>>>>> 2015-10-22 22:07 GMT+08:00 Simon Glass <s...@chromium.org>: >>>>>>> >>>>>>> Hi Lin, >>>>>>> >>>>>>> On 20 October 2015 at 20:37, Lin Huang <h...@rock-chips.com> wrote: >>>>>>>> >>>>>>>> it may not use SPL in other rockchip SOC, so move SUPPORT_SPL and >>>>>>>> SPL config to rk3288 configuration. >>>>>>>> >>>>>>>> Signed-off-by: Lin Huang <h...@rock-chips.com> >>>>>>>> --- >>>>>>>> Changes in v1: None >>>>>>>> >>>>>>>> arch/arm/Kconfig | 2 -- >>>>>>>> arch/arm/mach-rockchip/Kconfig | 2 ++ >>>>>>>> 2 files changed, 2 insertions(+), 2 deletions(-) >>>>>>>> >>>>>>>> diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig >>>>>>>> index 194fb7b..40fa741 100644 >>>>>>>> --- a/arch/arm/Kconfig >>>>>>>> +++ b/arch/arm/Kconfig >>>>>>>> @@ -831,8 +831,6 @@ config TARGET_STM32F429_DISCOVERY >>>>>>>> >>>>>>>> config ARCH_ROCKCHIP >>>>>>>> bool "Support Rockchip SoCs" >>>>>>>> - select SUPPORT_SPL >>>>>>>> - select SPL >>>>>>>> select OF_CONTROL >>>>>>>> select CPU_V7 >>>>>>>> select DM >>>>>>>> diff --git a/arch/arm/mach-rockchip/Kconfig >>>>>>>> b/arch/arm/mach-rockchip/Kconfig >>>>>>>> index ab50f4e..15cd380 100644 >>>>>>>> --- a/arch/arm/mach-rockchip/Kconfig >>>>>>>> +++ b/arch/arm/mach-rockchip/Kconfig >>>>>>>> @@ -2,6 +2,8 @@ if ARCH_ROCKCHIP >>>>>>>> >>>>>>>> config ROCKCHIP_RK3288 >>>>>>>> bool "Support Rockchip RK3288" >>>>>>>> + select SUPPORT_SPL >>>>>>>> + select SPL >>>>>>>> help >>>>>>>> The Rockchip RK3288 is a ARM-based SoC with a quad-core >>>>>>>> Cortex-A17 >>>>>>>> including NEON and GPU, 1MB L2 cache, Mali-T7 graphics, >>>>>>>> two >>>>>>>> -- >>>>>>>> 1.9.1 >>>>>>>> >>>>>>> We should avoid little binary blobs for booting the chip. I think we >>>>>>> can live with this as a stepping stone to having a proper SPL, but >>>>>>> what is the plan for a proper SPL in U-Boot? >>>>>> >>>>>> RK3036 have only 8k sram. 4k used by boot rom. The ddr initialize code >>>>>> is >>>>>> almost 4k. So i don't think we can do SPL. >>>>> >>>>> How does U-Boot get loaded in this case? Does it use ROM code? If so >>>> >>>> Yes, it use boot rom code to load U-Boot >>>>> >>>>> then I think we should create an SPL that handles the DDR init and >>>>> then returns to the ROM code for loading U-Boot. Also we should >>>>> document how this works in the README. >>>> >>>> It is a good news you agree we can return to boot rom from SPL. Do you >>>> know >>>> what size of sram a smallest SPL need? >>> >>> Exynos does something a little similar - it has a jump table of ROM >>> routines that SPL can call. >>> >>> You can essentially write your own code for SPL. I very much hope you >>> can use start.S and cro0.S, but these add up to a tiny amount of code >>> so should not cause problems. You should be able to put all of your >>> code into your implementation of board_init_f(), using most of the 4KB >>> available. U-Boot's SPL framework does add some overhead, but if you >>> leave out the board_init_r() implementation this is very small. >>> >>> If you do get stuck and find the size if over 4KB we should discuss it >>> and see what can be done. >> >> >> Okay, i will reference exynos to see how to do, thank you. >> > > One last point... U-Boot is written in C so as much as possible of this > should be C, rather than assembler. > > > Thank you for pointing that. I try to get a clean SPL(only timer and > uart driver), and it can work now, > it take about 600 bytes, i will start to port ddr driver.
Sounds good! Thanks, Simon _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot