[U-Boot] [RFC PATCH v2 13/20] fastboot: Merge reboot-bootloader handling

[Jocelyn Bohr <bohr@google.com>]

On Tue, May 1, 2018 at 1:21 AM Alex Kiernan <alex.kiernan@gmail.com> wrote:

> On Tue, May 1, 2018 at 8:22 AM Alex Kiernan <alex.kiernan@gmail.com>
> wrote:
>
>
> > On Tue, May 1, 2018 at 7:50 AM Jocelyn Bohr <bohr@google.com> wrote:
>
>
>
> > > On Mon, Apr 30, 2018 at 1:33 AM Alex Kiernan <alex.kiernan@gmail.com>
> > wrote:
>
> > >> Extract fb_set_reboot_flag() from USB code and ensure all the overides
> > >> are included, then make the UDP fastboot code go through this same
> > >> path.
>
> > >> Note this changes the behaviour of the fastboot net code such that
> > >> "reboot-bootloader" is no longer written to CONFIG_FASTBOOT_BUF_ADDR
> for
> > >> use as a marker on reboot (the AOSP code in
> common/android-bootloader.c
> > >> uses this marker - this code could be reinstated there if that gets
> > >> merged).
>
> > >> Signed-off-by: Alex Kiernan <alex.kiernan@gmail.com>
> > >> ---
>
> > >> Changes in v2: None
>
> > >>   arch/arm/mach-omap2/boot-common.c     |  2 +-
> > >>   arch/arm/mach-rockchip/rk3128-board.c |  2 +-
> > >>   arch/arm/mach-rockchip/rk322x-board.c |  2 +-
> > >>   drivers/fastboot/fb_common.c          |  5 +++++
> > >>   drivers/usb/gadget/f_fastboot.c       |  5 -----
> > >>   include/fastboot.h                    |  1 +
> > >>   net/fastboot.c                        | 17 +++++++++--------
> > >>   7 files changed, 18 insertions(+), 16 deletions(-)
>
> > >> diff --git a/arch/arm/mach-omap2/boot-common.c
> > b/arch/arm/mach-omap2/boot-common.c
> > >> index f9ab5da..2be5c11 100644
> > >> --- a/arch/arm/mach-omap2/boot-common.c
> > >> +++ b/arch/arm/mach-omap2/boot-common.c
> > >> @@ -238,7 +238,7 @@ void arch_preboot_os(void)
> > >>   }
> > >>   #endif
>
> > >> -#if defined(CONFIG_USB_FUNCTION_FASTBOOT) &&
> > !defined(CONFIG_ENV_IS_NOWHERE)
> > >> +#if CONFIG_IS_ENABLED(FASTBOOT) && !CONFIG_IS_ENABLED(ENV_IS_NOWHERE)
> > >>   int fb_set_reboot_flag(void)
> > >>   {
> > >>          printf("Setting reboot to fastboot flag ...\n");
> > >> diff --git a/arch/arm/mach-rockchip/rk3128-board.c
> > b/arch/arm/mach-rockchip/rk3128-board.c
> > >> index 2e8393d..00ad563 100644
> > >> --- a/arch/arm/mach-rockchip/rk3128-board.c
> > >> +++ b/arch/arm/mach-rockchip/rk3128-board.c
> > >> @@ -112,7 +112,7 @@ int board_usb_cleanup(int index, enum
> usb_init_type
> > init)
> > >>   }
> > >>   #endif
>
> > >> -#if defined(CONFIG_USB_FUNCTION_FASTBOOT)
> > >> +#if CONFIG_IS_ENABLED(FASTBOOT)
> > >>   int fb_set_reboot_flag(void)
> > >>   {
> > >>          struct rk3128_grf *grf;
> > >> diff --git a/arch/arm/mach-rockchip/rk322x-board.c
> > b/arch/arm/mach-rockchip/rk322x-board.c
> > >> index 8642a90..0ddfac8 100644
> > >> --- a/arch/arm/mach-rockchip/rk322x-board.c
> > >> +++ b/arch/arm/mach-rockchip/rk322x-board.c
> > >> @@ -140,7 +140,7 @@ int board_usb_cleanup(int index, enum
> usb_init_type
> > init)
> > >>   }
> > >>   #endif
>
> > >> -#if defined(CONFIG_USB_FUNCTION_FASTBOOT)
> > >> +#if CONFIG_IS_ENABLED(FASTBOOT)
> > >>   int fb_set_reboot_flag(void)
> > >>   {
> > >>          struct rk322x_grf *grf;
> > >> diff --git a/drivers/fastboot/fb_common.c
> b/drivers/fastboot/fb_common.c
> > >> index 8b3627b..36ef669 100644
> > >> --- a/drivers/fastboot/fb_common.c
> > >> +++ b/drivers/fastboot/fb_common.c
> > >> @@ -102,3 +102,8 @@ int fastboot_lookup_command(const char
> *cmd_string)
>
> > >>          return -1;
> > >>   }
> > >> +
> > >> +int __weak fb_set_reboot_flag(void)
> > >> +{
> > >> +       return -1;
> > >> +}
>
> > > Instead could this write the string "reboot-bootloader" to
> > CONFIG_FASTBOOT_BUF_ADDR?
>
>
> > I guess the thing you lose is you don't then get a default "I don't know
> > how to do that" response. Am I right in thinking you're only using this
> > behaviour on Raspberry Pi, or is it broader?
>
>
> Thinking about this some more... if we moved that string write into the
> default fb_set_reboot_flag implementation and then guarded the
> reboot-bootloader command with a new Kconfig symbol, you could get the "I
> don't know how to do that" behaviour by disabling the command?
>

The "reboot-bootloader" behavior isn't RPi specific, it's part of the
fastboot
protocol and is required by all Android bootloaders that support fastboot.

https://android.googlesource.com/platform/system/core/+/master/fastboot/

So my thinking was that since it's part of the protocol, the weak function
could
have some default implementation. I can't think of a reason for a device to
support fastboot but not the "reboot-bootloader" command.

-- 
> Alex Kiernan
>