Hi Simon, Stephen,
On Mon, 23 Feb 2015 10:44:54 -0700 Simon Glass sjg@chromium.org wrote:
Hi Stephen,
On 23 February 2015 at 10:33, Stephen Warren swarren@wwwdotorg.org wrote:
On 02/23/2015 07:02 AM, Simon Glass wrote:
Hi Masahiro,
On 20 February 2015 at 19:37, Masahiro YAMADA yamada.m@jp.panasonic.com wrote:
Hi Simon,
2015-02-21 11:28 GMT+09:00 Simon Glass sjg@chromium.org:
Hi Masahiro,
On 20 February 2015 at 17:54, Masahiro YAMADA yamada.m@jp.panasonic.com wrote:
Hi Simon, Stephen,
2015-02-21 3:39 GMT+09:00 Simon Glass sjg@chromium.org: > > Hi, > > On 20 February 2015 at 10:54, Stephen Warren swarren@wwwdotorg.org > wrote: >> >> On 02/20/2015 10:06 AM, Simon Glass wrote: >>> >>> >>> +Stephen >>> >>> Hi Masahiro, >>> >>> On 19 February 2015 at 22:25, Masahiro Yamada >>> yamada.m@jp.panasonic.com >>> wrote: >>>> >>>> >>>> Now CONFIG_SPL_BUILD is not defined in Kconfig, so >>>> "!depends on SPL_BUILD" and "if !SPL_BUILD" are redundant. >> >> >> >>>> diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig >>>> index 41f3220..700e2a8 100644 >>>> --- a/arch/arm/Kconfig >>>> +++ b/arch/arm/Kconfig >>>> @@ -739,9 +739,8 @@ config TEGRA >>>> bool "NVIDIA Tegra" >>>> select SUPPORT_SPL >>>> select SPL >>>> - select OF_CONTROL if !SPL_BUILD >>>> - select CPU_ARM720T if SPL_BUILD >>>> - select CPU_V7 if !SPL_BUILD >>>> + select OF_CONTROL >>>> + select CPU_V7 >>> >>> >>> >>> Sorry if I have missed something here. On Tegra most unfortunately >>> the >>> SPL uses ARMv4t and U-Boot proper uses ARMv7. In fact that is the >>> only >>> reason that Tegra has SPL. Doesn't this change with this commit?
No. I think behavior is still the same as before.
In a single .config, we cannot define two CPUs in Kconfig.
So, we only define CPU_V7, for the main processors.
For SPL, we override the "CPU" in config.mk
ifdef CONFIG_SPL_BUILD ifdef CONFIG_TEGRA CPU := arm720t endif endif
I know what you might be saying is, this is too ugly. Yes.
I think we can do a little better with further rafactoring, but the basic idea is, SPL of Tegra is a special case.
Yes I saw that, I understand now. So SPL_BUILD is no longer available in Kconfig, but is still available in Makefiles, right?
Yes, exactly!
This all works fine on Tegra for me. However I like to suggest dropping a few patches in this series.
I don't think it is worth using ARCH_MALLOC_F_LEN. In fact for me the Tegra defconfig looks OK and SPL is built correctly.
My remaining question is about that Tegra seems to want USE_PRIVATE_LIBGCC for SPL but not for U-Boot. I'm not sure why, nor whether it matters. It seems to work find using it for both.
Depending on the toolchain, we actively need USE_PRIVATE_LIBGCC for SPL, and don't /need/ it for non-SPL. However, enabling USE_PRIVATE_LIBGCC for non-SPL likely won't hurt.
The issue is that the libgcc bundled with most compilers is for ARMv7 (since we tend to use ARMv7 compilers, since the main U-boot is built for ARMv7). That bundled libgcc won't work on the ARMv4 that runs the SPL, so we need USE_PRIVATE_LIBGCC there. The private libgcc bundled with U-Boot should work fine when built for either CPU, so it is OK to always use it, rather than only use it when strictly needed.
Ah yes, I think I knew that once. So in short Masahiro's patch here should be fine.
Yes, Stephen explained all about my intention.
I think CONFIG_USE_PRIVATE_LIBGCC is also necessary for Raspberry Pi 1 for example.
Moreover, I had already posted this patch: http://patchwork.ozlabs.org/patch/438360/
I'd like to expand the private library to all the ARM boards.
Linux Kernel includes the library in its source tree.
I think it is generally a good idea to reduce the depencendy on particular toolchains. Agree?
Best Regards Masahiro Yamada