Hi Stefano,
On 05/10/2012 10:16, Lukasz Majewski wrote:
It is necessary to introduce a new system wide function- power_board_init()
It turns out, that power initialization must be done as early as possible. In the case of PMIC framework redesign, which aims to support multiple instances of PMIC devices the initialization shall be performed just after malloc configuration.
The arch_early_init_r() could be used instead, but it doesn't reflect that the "power" subsystem is going to be initialized.
Signed-off-by: Lukasz Majewski l.majewski@samsung.com Signed-off-by: Kyungmin Park kyungmin.park@samsung.com
Changes for v2:
- None
Hi Lucasz,
only to make some order. We have already several entries that calls board specific functions.
There is at least board_init() and board_late_init(). The last one was use mostly for the pmic initialization up nowm because it is called after malloc_init().
Now you want to add a new one. This means we have cases where the PMIC must be initialized before flash, right ?
The case is that PMIC (and other devices) needs to be setup after malloc init and before MMC (in our case). The board_init() is before malloc init and board_late_init() is after MMC initialization for which working PMIC is necessary. PMIC_v1 works since there is a single, static instance of PMIC device (no lists needed).
Filling the above gap was my motivation to define special callback for power.
In the ./arch/arm/lib/board.c there is #ifdef CONFIG_ARCH_EARLY_INIT_R arch_early_init_r(); #endif
Which could be used and defined at e.g. ./boards/samsung/trats.c However it is only ARM specific (not available at PPC) and the name is a bit misleading. (frankly speaking it is a dead code).
We use often the "weak" mechanism to avoid that a board maintainer is constrained to implement an empty function only to make happy the linker. It is better to declare the function as weak and call it with the same schema, such as board_power_init() (several board_* are weak)
Correct me if I'm wrong, but weren't we recently trying to remove functions defined as weak? One of arguments was that weak function will allow to build a u-boot.bin, which then crash at null pointer dereference when proper CONFIG not selected.
arch/arm/lib/board.c | 4 ++++ include/common.h | 3 +++ 2 files changed, 7 insertions(+), 0 deletions(-)
diff --git a/arch/arm/lib/board.c b/arch/arm/lib/board.c index 109a1ac..431ef5b 100644 --- a/arch/arm/lib/board.c +++ b/arch/arm/lib/board.c @@ -513,6 +513,10 @@ void board_init_r(gd_t *id, ulong dest_addr) arch_early_init_r(); #endif
+#ifdef CONFIG_POWER_INIT
- power_board_init();
Do we need a config option only for calling this ? I think that the decision can be taken with CONFIG_PMIC, declaring the function as weak.
This is one of options -> __weak power_board_init() would be defined when no CONFIG_PMIC defined. Good idea, since one CONFIG_POWER_* option would be removed.
+#endif
#if !defined(CONFIG_SYS_NO_FLASH) puts("Flash: ");
diff --git a/include/common.h b/include/common.h index a7fb05e..5cc859f 100644 --- a/include/common.h +++ b/include/common.h @@ -487,6 +487,9 @@ int board_late_init (void); int board_postclk_init (void); /* after clocks/timebase, before env/serial */ int board_early_init_r (void); void board_poweroff (void); +#ifdef CONFIG_POWER_INIT +int power_board_init(void); +#endif
#if defined(CONFIG_SYS_DRAM_TEST) int testdram(void);
Best regards, Stefano Babic