[PATCH v2 4/4] board_f.c: Insure 16 alignment of start_addr_sp and reserved memory

[Stephen Warren]

On 1/22/20 6:52 AM, Patrick Delaunay wrote:
> Add a function reserve_sp() to reserved memory with 16 bits alignment
> after the stack pointer (gd->start_addr_sp) and use this new function
> in board_f.c to reserve all the memory area (malloc, board, gd, fdt,
> bootstage, stacks).
> 
> This 16 byte alignment is needed for cast on struct pointer
> for the reserved memory, for example:
> + x86_64 ABI: https://reviews.llvm.org/D30049: 16 bytes
> + ARMv8 Instruction Set Overview: quad word, 16 bytes
> 
> An other alignment value could be needed for other architecture.

> diff --git a/common/board_f.c b/common/board_f.c

>   
> +/*
> + * reserve after start_addr_sp the requested size and make the stack pointer
> + * 16-byte aligned, this alignment is needed for cast on the reserved memory
> + * ref = x86_64 ABI: https://reviews.llvm.org/D30049: 16 bytes
> + *     = ARMv8 Instruction Set Overview: quad word, 16 bytes
> + */
> +static unsigned long reserve_sp(size_t size)

Bikeshed: Not sure this name is very description. Perhaps 
reserve_stack_aligned() would be better. Not a big deal though. Patches 
1,4 look fine otherwise.