On 10/15/22 21:46, Simon Glass wrote:
Hi Heinrich,
On Sat, 15 Oct 2022 at 13:29, Heinrich Schuchardt xypron.glpk@gmx.de wrote:
Am 15. Oktober 2022 21:24:36 MESZ schrieb Simon Glass sjg@chromium.org:
Hi Heinrich,
On Sat, 15 Oct 2022 at 13:05, Heinrich Schuchardt xypron.glpk@gmx.de wrote:
On 10/15/22 20:39, Simon Glass wrote:
Hi Heinrich,
On Sat, 15 Oct 2022 at 12:31, Heinrich Schuchardt xypron.glpk@gmx.de wrote:
On 10/15/22 19:53, Simon Glass wrote: > Hi Michal, > > On Fri, 14 Oct 2022 at 14:53, Michal Suchanek msuchanek@suse.de wrote: >> >> Currently sandbox configuration defautls to 64bit and there is no >> automation for building 32bit sandbox on 32bit hosts. >> >> Use _LP64 macro as heuristic for detecting 64bit targets. >> >> Signed-off-by: Michal Suchanek msuchanek@suse.de >> --- >> >> Changes in v2: >> simplify and move detection to kconfig >> >> --- >> arch/sandbox/Kconfig | 18 +++--------------- >> scripts/Kconfig.include | 4 ++++ >> 2 files changed, 7 insertions(+), 15 deletions(-) > > Reviewed-by: Simon Glass sjg@chromium.org > > My only question is whether we can allow building the 32-bit version > on a 64-bit machine? That would need a separate option I think, to > say: > > I don't want you to automatically determine HOST_32/64BIT. Instead, > use 32 (or 64). > > This is along the lines of what Heinrich is saying, except that I > strongly feel that we must do the right thing by default, as your > patch does.
The whole point of phys_addr_t and phys_size_t is that it can be 64bit or 32bit on ilp32.
With this patch we cannot build with CONFIG_PHYS_64BIT=y on ilp32 and that is bad.
32 bit phys_addr_t on lp64 is irrelevant for actual hardware but this is what we currently test with sandbox_defconfig on Gitlab CI.
My patch is ending up in the same behavior as Michal's patch except that it allows to have 64bit phys_addr_t on ilp32.
It needs to automatically default to 32 or 64 bit depending on the host. If the user wants to fiddle with Kconfig to force it to the other one, that should be possible to.
It looks like your patch requires manual configuration, but perhaps I just misunderstood it?
__LP64__ is a symbol defined by the compiler when compiling for 64bit and not defined when compiling for 32bit systems. There is nothing manual about it.
My patch uses this symbol to replace HOST_32BIT and HOST_64BIT.
Michal's patch compiles a program tools/bits-per-long.c that ends up returning 64 on 64 bit systems (where __LP64__ is defined) and 32 on 32 bit systems (where __LP64__ is not defined) and then chooses HOST_32BIT and HOST_64BIT accordingly. This part of Michal's patch is not wrong. The solution is only overly complicated.
What has to be chosen manually with both patches is PHYS_64BIT e.g. by selecting sandbox64_defconfig instead of sandbox_defconfig.
Unfortunately Michal did not understand that PHYS_64BIT=y, HOST_32BIT=y is a necessary test scenario and introduced an invalid dependency.
With my patch sandbox64_defconfig on a 32bit system uses 64bit phys_addr_t.
With Michal's patch sandbox64_defconfig on a 32bit system uses 32bit phys_addr_t.
That's all great, thank you, but please can you address my actual question?
Your question in this thread was if my patch requires extra manual configuration compared to Michal's patch and the answer was no.
What other question do you have?
"It needs to automatically default to 32 or 64 bit depending on the host. If the user wants to fiddle with Kconfig to force it to the other one, that should be possible to."
The user forces 32bit or 64bit by selecting a 32bit or 64bit compiler not with Kconfig. PHYS_64BIT is the only thing that needs to be selected via Kconfig.
I am not talking about anyone's patch, actually, just trying to state what I think should happen.
The physical systems that U-Boot has to deal with are:
* 32bit without physical address extension (PAE) Here phys_addr_t must be 32 bit. * 32bit with physical address extension. Here phys_addr_t must be 64 bit. * 64bit systems without PAE. Here phys_addr_t must be 64 bit.
We want to model these three scenarios with the sandbox.
So we have to build:
* Sandbox with PHYS_64BIT=n using a 32bit compiler. * Sandbox with PHYS_64BIT=y using a 32bit compiler. * Sandbox with PHYS_64BIT=y using a 64bit compiler.
Sandbox with PHYS_64BIT=n and using a 64bit compiler is irrelevant as it does not match any physical system.
PHYS_64BIT selecting HOST_64BIT=y was always wrong.
Best regards
Heinrich