[PATCH] arm: mach-k3: am6_init: Use CONFIG_TI_I2C_BOARD_DETECT

[Bryan Brattlof]

On this day, February 14, 2022, thus sayeth Christian Gmeiner:
> Hi Bryan.
> 
> >
> > On this day, February  7, 2022, thus sayeth Christian Gmeiner:
> > > We only want to call bo_board_detect() if CONFIG_TI_I2C_BOARD_DETECT
> >
> > s/bo_board_detect/do_board_detect/
> 
> Upps..
> 
> >
> > > is set. Same as done for am64.
> > >
> > > Signed-off-by: Christian Gmeiner <christian.gmeiner at gmail.com>
> > > ---
> > >  arch/arm/mach-k3/am6_init.c | 3 ++-
> > >  1 file changed, 2 insertions(+), 1 deletion(-)
> > >
> > > diff --git a/arch/arm/mach-k3/am6_init.c b/arch/arm/mach-k3/am6_init.c
> > > index ffb7aaded2..8a6b1de764 100644
> > > --- a/arch/arm/mach-k3/am6_init.c
> > > +++ b/arch/arm/mach-k3/am6_init.c
> > > @@ -251,7 +251,8 @@ void board_init_f(ulong dummy)
> > >       k3_sysfw_print_ver();
> > >
> > >       /* Perform EEPROM-based board detection */
> > > -     do_board_detect();
> > > +     if (IS_ENABLED(CONFIG_TI_I2C_BOARD_DETECT))
> > > +             do_board_detect();
> > >
> >
> > Unless I'm mistaken the AM65 and AM64 use different do_board_detect()s.
> 
> They use the same mechanism (read a i2c eeprom and interpret these values)
> 
> > This one being defined inside board/ti/am65x/evm.c
> >
> > At least that's why I think I get this nasty error when I try to build
> > with CONFIG_TI_I2C_BOARD_DETECT turned off and your patch applied.
> >
> 
> config TARGET_AM654_A53_EVM and TARGET_AM654_R5_EVM both imply
> TI_I2C_BOARD_DETECT so
> manually disabling CONFIG_TI_I2C_BOARD_DETECT will hurt.
> 
> >
> > ard/ti/am65x/evm.c: In function ‘do_board_detect’:
> > board/ti/am65x/evm.c:136:35: error: ‘CONFIG_EEPROM_BUS_ADDRESS’ undeclared (first use in this function)
> >   136 |  ret = ti_i2c_eeprom_am6_get_base(CONFIG_EEPROM_BUS_ADDRESS,
> >       |                                   ^~~~~~~~~~~~~~~~~~~~~~~~~
> > board/ti/am65x/evm.c:136:35: note: each undeclared identifier is reported only once for each function it appears in
> > board/ti/am65x/evm.c:137:7: error: ‘CONFIG_EEPROM_CHIP_ADDRESS’ undeclared (first use in this function)
> >   137 |       CONFIG_EEPROM_CHIP_ADDRESS);
> >       |       ^~~~~~~~~~~~~~~~~~~~~~~~~~
> > board/ti/am65x/evm.c: In function ‘setup_board_eeprom_env’:
> > board/ti/am65x/evm.c:172:2: warning: implicit declaration of function ‘set_board_info_env_am6’ [-Wimplicit-function-declaration]
> >   172 |  set_board_info_env_am6(name);
> >       |  ^~~~~~~~~~~~~~~~~~~~~~
> > board/ti/am65x/evm.c: In function ‘probe_daughtercards’:
> > board/ti/am65x/evm.c:283:31: error: ‘CONFIG_EEPROM_BUS_ADDRESS’ undeclared (first use in this function)
> >   283 |   ret = ti_i2c_eeprom_am6_get(CONFIG_EEPROM_BUS_ADDRESS, i2c_addr,
> >       |                               ^~~~~~~~~~~~~~~~~~~~~~~~~
> > board/ti/am65x/evm.c: In function ‘board_late_init’:
> > board/ti/am65x/evm.c:369:2: warning: implicit declaration of function ‘board_ti_am6_set_ethaddr’ [-Wimplicit-function-declaration]
> >   369 |  board_ti_am6_set_ethaddr(1, ep->mac_addr_cnt);
> >       |  ^~~~~~~~~~~~~~~~~~~~~~~~
> >
> >
> 
> Okay.. that was expected as CONFIG_EEPROM_BUS_ADDRESS depends on
> CONFIG_TI_I2C_BOARD_DETECT
> see board/ti/common/Kconfig
> 
> > I will say I just turned CONFIG_TI_I2C_BOARD_DETECT off and chose the
> > default options defconfig offered me. The chances are high I goofed on
> > something.
> >
> 
> Okay.. so you have not used something like am65x_evm_a53_defconfig?
> 
> I am working on a custom am65 based board where I do not have an i2c
> eeprom and do not want to use TI's
> board detection thing.
> 
> AFAICT am642 does it the same way and there are no problems.
>

I'm currently building the .config like so:

  $ make ARCH=arm CROSS_COMPILE= ... am65x_evm_a53_defconfig
  $ cp .config .config.default
  $ make ARCH=arm CROSS_COMPILE= ... menuconfig

  ARM architecture -> Support for Board detection for TI platforms

Disabling CONFIG_TI_I2C_BOARD_DETECT and producing this diff

  $ diff .config.default .config
  180,182c180
  < CONFIG_TI_I2C_BOARD_DETECT=y
  < CONFIG_EEPROM_BUS_ADDRESS=0
  < CONFIG_EEPROM_CHIP_ADDRESS=0x50
  ---
  > # CONFIG_TI_I2C_BOARD_DETECT is not set

My thinking is this do_board_detect() is not protected with an #ifdef 
like the one in board/ti/am64x/evm.c which is causing the disappearance 
of CONFIG_EEPROM_BUS_ADDRESS and CONFIG_EEPROM_CHIP_ADDRESS to break my 
build.

I haven't look much further, but it seems like we need to do more to 
stop the compiler from worrying about dead code.

~Bryan