Hi Heinrich,
On Tue, 26 Nov 2024 at 02:10, Heinrich Schuchardt xypron.glpk@gmx.de wrote:
On 25.11.24 21:44, Simon Glass wrote:
The EFI-loader implementation converts things back and forth between addresses and pointers, with not much consistency in how this is done.
Within most of U-Boot a pointer is a void * and an address is a ulong
No. It is phys_addr_t that was introduced to handle the sandbox's virtual addresses.
And we should keep this sandbox stuff out of the EFI code. They are only needed for the command line interface.
No. My statement is correct and long predates sandbox. U-Boot has always used ulong. Using an address is generally much easier than a pointer, so I believe this design decision was (and remains) a good one. I certainly would not support changing it. The phys_addr_t type has nothing to do with sandbox.
This convention is very helpful, since it is obvious in common code as to whether you need to call map_sysmem() and friends, or not.
As part of cleaning up the EFI memory-management, I found it almost impossible to know in some cases whether something is an address or a pointer. I decided to give up on that and come back to it when this is resolved.
This series starts applying the normal ulong/void * convention to the EFI_loader code, so making things easier to follow.
According to the C specification size of long may be different to the size of void *. uintptr_t is the type that is guaranteed to match the size of void *.
There is no benefit in spreading the ulong abuse any further.
U-Boot specifically uses compilers where ulong can hold a pointer. Same with Linux.
Regards, Simon