[U-Boot] [PATCH v5 00/18] rockchip: back-to-bootrom: replace assembly-implementation with C-code

[Philipp Tomsich <philipp.tomsich@theobroma-systems.com>]

Recent discussions confirmed (what the code always assumed): the
Rockchip BROM always enters U-Boot with the stack-pointer valid
(i.e. the U-Boot startup code is running off the BROM stack).

We can thus replace the back-to-bootrom code (i.e. both the
save_boot_params and back_to_bootrom implementations) using C-code
based on setjmp/longjmp.  The new implementation is already structured
to allow an easy drop-in of Andy's changes to enter download-mode when
returning to the BROM.

This turned out to require a some tweaking to system.h (making sure
that the prototype for save_boot_params_ret is visible for A64)and
start.S (so binutils knows that this is a possible function entry and
it can correctly insert A32-to-Thumb transitions) and taking the axe
to setjmp.h (which created quite a few issues with it not expecting
A32/T32/Thumb call-sites and some fragility from GCC being smart about
the clobber-list of the inline assembly... which led to r9 not being
saved or restored).

For v4+: To fix issues with the RK3188 support, this also updates the
boot0 hook changes (i.e. allowing the boot0-hook to insert code/data
before the ARM vector table) that Kever had submitted this spring and
implements a similar "early back-to-bootrom" as suggested by Pawel
(for the RK3066) as a generic mechanism.


Changes in v5:
- set return value to 0 before returning to the BROM

Changes in v4:
- after merging the 'back-to-bootrom' series with the 'boot0-hook'
  series, this drops the TPL stub and builds only a single SPL image
  that uses the 'early back-to-bootrom' logic originally implemented
  by Pawel for the RK3066.
- changes the SPL_STACK_BASE to +0x800 (from +0x804), as the boot0
  hook already reserves the space for the SPL magic (previously
  inserted by mkimage)
- no longer updates rk3188-board-tpl.c (as we have just removed it
  in an earlier commit)

Changes in v3:
- tracked the root-cause why no interwork branch was emitted and fixed
  it using a '.type'-directive in start.S to mark save_boot_params_ret
  as a (possible) function-entry.
- converted setjmp/longjmp from inline-assembly to separate .S files
  to improve predicatability if emitted code

Changes in v2:
- [added in v2] chain back_to_bootrom calls for SPL, first returning
  to the TPL (using the same mechanism) and the to the BROM from the
  TPL
- also covers the RK3188 (which I had originally missed)

Kever Yang (3):
  rockchip: boot0: align to 0x20 for armv7 '_start'
  rockchip: mkimage: use spl_boot0 for all Rockchip SoCs
  rockchip: rk3288: use aligned address for SPL_TEXT_BASE

Philipp Tomsich (15):
  arm: boot0 hook: move boot0 hook before '_start'
  rockchip: enable boot0-hook for all Rockchip SoCs
  rockchip: rk3036: use aligned address for SPL_TEXT_BASE
  socfpga: boot0 hook: adjust to unified boot0 semantics
  bcm235xx: boot0 hook: adjust to unified boot0 semantics
  bcm281xx: boot0 hook: adjust to unified boot0 semantics
  rockchip: boot0 hook: support early return for RK3188/RK3066-style
    BROM
  arm: make save_boot_params_ret prototype visible for AArch64
  arm: mark save_boot_params_ret as a function
  arm: provide a PCS-compliant setjmp implementation
  rockchip: back-to-bootrom: replace assembly-implementation with C-code
  rockchip: rk3188: use boot0 hook to load up SPL in 2 steps
  rockchip: back-to-bootrom: allow passing a cmd to the bootrom
  rockchip: rk3188: move CONFIG_SPL_* entries from rk3188_common.h to
    Kconfig
  rockchip: mkimage: remove unused code-paths (spl_boot0 is now implied)

 arch/arm/Kconfig                             |  1 +
 arch/arm/cpu/armv7/start.S                   |  1 +
 arch/arm/include/asm/arch-bcm235xx/boot0.h   |  2 +
 arch/arm/include/asm/arch-bcm281xx/boot0.h   |  2 +
 arch/arm/include/asm/arch-rockchip/boot0.h   | 38 ++++++++---
 arch/arm/include/asm/arch-rockchip/bootrom.h | 30 ++++++---
 arch/arm/include/asm/setjmp.h                | 94 ++++------------------------
 arch/arm/include/asm/system.h                | 62 +++++++++---------
 arch/arm/lib/Makefile                        |  6 ++
 arch/arm/lib/setjmp.S                        | 37 +++++++++++
 arch/arm/lib/setjmp_aarch64.S                | 42 +++++++++++++
 arch/arm/lib/vectors.S                       | 54 ++++++++++------
 arch/arm/mach-rockchip/Kconfig               | 39 ++++++++++--
 arch/arm/mach-rockchip/Makefile              |  5 +-
 arch/arm/mach-rockchip/bootrom.c             | 54 +++++++++++++++-
 arch/arm/mach-rockchip/rk3036-board-spl.c    |  2 +-
 arch/arm/mach-rockchip/rk3188-board-spl.c    | 14 +----
 arch/arm/mach-rockchip/rk3188-board-tpl.c    | 86 -------------------------
 arch/arm/mach-rockchip/rk322x-board-spl.c    |  2 +-
 arch/arm/mach-rockchip/rk3288-board-spl.c    |  4 +-
 arch/arm/mach-rockchip/rk3288-board-tpl.c    |  2 +-
 arch/arm/mach-rockchip/rk3368-board-tpl.c    |  2 +-
 arch/arm/mach-rockchip/rk3399-board-spl.c    |  2 +-
 arch/arm/mach-rockchip/save_boot_param.S     | 69 --------------------
 arch/arm/mach-socfpga/include/mach/boot0.h   |  3 +
 doc/README.rockchip                          | 10 +--
 include/configs/rk3036_common.h              |  2 +-
 include/configs/rk3188_common.h              | 18 +-----
 include/configs/rk3288_common.h              |  2 +-
 tools/rkcommon.c                             | 45 +++++--------
 30 files changed, 348 insertions(+), 382 deletions(-)
 create mode 100644 arch/arm/lib/setjmp.S
 create mode 100644 arch/arm/lib/setjmp_aarch64.S
 delete mode 100644 arch/arm/mach-rockchip/rk3188-board-tpl.c
 delete mode 100644 arch/arm/mach-rockchip/save_boot_param.S

-- 
2.1.4