u-boot/include/asm-generic
Rasmus Villemoes 50128aeb0f cyclic: get rid of cyclic_init()
Currently, we must call cyclic_init() at some point before
cyclic_register() becomes possible. That turns out to be somewhat
awkward, especially with SPL, and has resulted in a watchdog callback
not being registered, thus causing the board to prematurely reset.

We already rely on gd->cyclic reliably being set to NULL by the asm
code that clears all of gd. Now that the cyclic list is a hlist, and
thus an empty list is represented by a NULL head pointer, and struct
cyclic_drv has no other members, we can just as well drop a level of
indirection and put the hlist_head directly in struct
global_data. This doesn't increase the size of struct global_data,
gets rid of an early malloc(), and generates slightly smaller code.

But primarily, this avoids having to call cyclic_init() early; the cyclic
infrastructure is simply ready to register callbacks as soon as we
enter C code.

We can still end up with schedule() being called from asm very early,
so we still need to check that gd itself has been properly initialized
[*], but once it has, gd->cyclic_list is perfectly fine to access, and
will just be an empty list.

As for cyclic_uninit(), it was never really the opposite of
cyclic_init() since it didn't free the struct cyclic_drv nor set
gd->cyclic to NULL. Rename it to cyclic_unregister_all() and use that
in test/, and also insert a call at the end of the board_init_f
sequence so that gd->cyclic_list is a fresh empty list before we enter
board_init_r().

A small piece of ugliness is that I had to add a cast in
cyclic_get_list() to silence a "discards 'volatile' qualifier"
warning, but that is completely equivalent to the existing handling of
the uclass_root_s list_head member.

[*] I'm not really sure where we guarantee that the register used for
gd contains 0 until it gets explicitly initialized, but that must be
the case, otherwise testing gd for being NULL would not make much sense.

Signed-off-by: Rasmus Villemoes <rasmus.villemoes@prevas.dk>
Reviewed-by: Stefan Roese <sr@denx.de>
Tested-by: Stefan Roese <sr@denx.de>
Tested-by: Tim Harvey <tharvey@gateworks.com> # imx8mm-venice-*
2022-11-02 08:42:03 +01:00
..
bitops include: Add generic bitops headers 2015-11-05 10:51:57 -05:00
atomic-long.h atomic-long: Fix warnings on arm64 2018-01-28 09:39:05 -05:00
atomic.h Add include/asm-generic/atomic.h 2018-09-25 21:49:18 -04:00
bitsperlong.h linux/bitops.h: GENMASK copy from linux 2015-10-21 09:14:07 -04:00
global_data.h cyclic: get rid of cyclic_init() 2022-11-02 08:42:03 +01:00
gpio.h gpio: sandbox: Add GPIOD_IS_AF for gpio configured in alternate function 2022-09-15 09:55:30 -04:00
int-ll64.h arch: types.h: factor out fixed width typedefs to int-ll64.h 2018-09-10 20:48:16 -04:00
io.h SPDX: Convert all of our single license tags to Linux Kernel style 2018-05-07 09:34:12 -04:00
ioctl.h x86: Fix support for booting bzImage 2010-05-06 00:17:01 +02:00
pe.h efi_loader: add Linux magic to aarch64 crt0 2021-01-29 20:22:40 +01:00
sections.h Revert "efi_capsule: Move signature from DTB to .rodata" 2021-09-18 03:47:50 -06:00
signal.h asm-generic/signal.h: import from linux 2010-01-17 20:36:05 -05:00
types.h arch: types.h: factor out fixed width typedefs to int-ll64.h 2018-09-10 20:48:16 -04:00
u-boot.h common/board_r.c: drop legacy and unused bi_enetaddr 2022-06-06 18:01:21 -04:00
unaligned.h efi_loader: allow unaligned memory access 2018-06-03 15:27:21 +02:00