There has been talk on and off of a pre-relocation malloc() implementation. Driver model needs this so that it can work before relocation.
A previous implementation was sent in a v1 series.
This implementation works by allocating space on the stack. The benefit is that boards do not need to specify the address of the malloc() area, only the size. The down-side is that due to the way board_init_f() is called, architecture-specific code needs to be used to allocate the space.
No clever algorithms are used to allocate space, free() is a nop and realloc() is not supported. This fits well with the desire to avoid wasting space on bucket tables and the hassle of supporting BSS data before relocation. We don't expect 'churn' in the pre-relocation case - we just want to allocate small amounts of memory temporarily.
After relocation a new malloc() pool is created and the old one is lost, although pointers into it will survive the immediate process of relocation.
Implementations are provided for sandbox and arm.
A related change is made to the early init for each arch to make this work.
Changes in v2: - Tidy up commit message typo
Simon Glass (9): Remove form-feeds from dlmalloc.c arm: Set up global data before board_init_f() sandbox: Set up global data before board_init_f() Add a simple malloc() implementation for pre-relocation arm: Support pre-relocation malloc() exynos: Enable pre-relocation malloc() sandbox: Support pre-relocation malloc() sandbox: config: Enable pre-relocation malloc() sandbox: Always enable malloc debug
README | 16 ++++++++ arch/arm/include/asm/config.h | 2 - arch/arm/lib/crt0.S | 11 +++++ arch/sandbox/cpu/start.c | 8 ++++ arch/sandbox/include/asm/config.h | 1 - common/board_f.c | 12 ++++++ common/board_r.c | 4 ++ common/dlmalloc.c | 85 ++++++++++++++++++++++++++++----------- include/asm-generic/global_data.h | 5 +++ include/configs/exynos5-dt.h | 4 +- include/configs/sandbox.h | 5 ++- lib/asm-offsets.c | 3 ++ 12 files changed, 127 insertions(+), 29 deletions(-)