When a previous phase of U-Boot has run we need to adjust the init of subsequent states to avoid messing up the CPU state.
Add a new version of the start logic for SPL, when it boots from TPL (start_from tpl.c) and a new version for U-Boot when it boots from SPL.
Signed-off-by: Simon Glass sjg@chromium.org ---
Changes in v2: - Add xorl to TPL code also - Update comments in start_from_tpl to correctly explain SPL state
arch/x86/Makefile | 12 ++++++ arch/x86/cpu/Makefile | 15 +++++++- arch/x86/cpu/start_from_spl.S | 71 +++++++++++++++++++++++++++++++++++ arch/x86/cpu/start_from_tpl.S | 49 ++++++++++++++++++++++++ 4 files changed, 146 insertions(+), 1 deletion(-) create mode 100644 arch/x86/cpu/start_from_spl.S create mode 100644 arch/x86/cpu/start_from_tpl.S
diff --git a/arch/x86/Makefile b/arch/x86/Makefile index fec14847cc5..9fd6cf2d3bb 100644 --- a/arch/x86/Makefile +++ b/arch/x86/Makefile @@ -4,9 +4,21 @@ ifeq ($(CONFIG_EFI_APP),) ifdef CONFIG_$(SPL_)X86_64 head-y := arch/x86/cpu/start64.o else +ifeq ($(CONFIG_$(SPL_TPL_)X86_16BIT_INIT),y) head-y := arch/x86/cpu/start.o +else +ifndef CONFIG_SPL +head-y := arch/x86/cpu/start.o +else +ifdef CONFIG_SPL_BUILD +head-y = arch/x86/cpu/start_from_tpl.o +else +head-y = arch/x86/cpu/start_from_spl.o +endif +endif endif endif +endif # EFI
head-$(CONFIG_$(SPL_)X86_16BIT_INIT) += arch/x86/cpu/start16.o head-$(CONFIG_$(SPL_)X86_16BIT_INIT) += arch/x86/cpu/resetvec.o diff --git a/arch/x86/cpu/Makefile b/arch/x86/cpu/Makefile index 54668aab240..85fd5e616ea 100644 --- a/arch/x86/cpu/Makefile +++ b/arch/x86/cpu/Makefile @@ -9,9 +9,22 @@ ifeq ($(CONFIG_$(SPL_)X86_64),y) extra-y = start64.o else +ifeq ($(CONFIG_$(SPL_TPL_)X86_16BIT_INIT),y) extra-y = start.o +else +ifndef CONFIG_SPL +extra-y = start.o +else +ifdef CONFIG_SPL_BUILD +extra-y = start_from_tpl.o +else +extra-y = start_from_spl.o endif -extra-$(CONFIG_$(SPL_)X86_16BIT_INIT) += resetvec.o start16.o +endif +endif +endif + +extra-$(CONFIG_$(SPL_TPL_)X86_16BIT_INIT) += resetvec.o start16.o
obj-y += cpu.o cpu_x86.o
diff --git a/arch/x86/cpu/start_from_spl.S b/arch/x86/cpu/start_from_spl.S new file mode 100644 index 00000000000..4d4e5d0758d --- /dev/null +++ b/arch/x86/cpu/start_from_spl.S @@ -0,0 +1,71 @@ +/* SPDX-License-Identifier: GPL-2.0+ */ +/* + * 32-bit x86 Startup Code when running from SPL + * + * Copyright 2018 Google, Inc + * Written by Simon Glass sjg@chromium.org + */ + +#include <config.h> + +.section .text.start +.code32 +.globl _start +.type _start, @function +_start: + /* Set up memory using the existing stack */ + movl $(CONFIG_SYS_CAR_ADDR + CONFIG_SYS_CAR_SIZE - 4), %eax +#ifdef CONFIG_DCACHE_RAM_MRC_VAR_SIZE + subl $CONFIG_DCACHE_RAM_MRC_VAR_SIZE, %eax +#endif + /* + * We don't subject CONFIG_DCACHE_RAM_MRC_VAR_SIZE since memory is + * already set up. This has the happy side-effect of putting gd in a + * new place separate from SPL, so the memset() in + * board_init_f_init_reserve() does not cause any problems (otherwise + * it would zero out the gd and crash) + */ + call board_init_f_alloc_reserve + mov %eax, %esp + + call board_init_f_init_reserve + + xorl %eax, %eax + call board_init_f + call board_init_f_r + + /* Should not return here */ + jmp . + +.globl board_init_f_r_trampoline +.type board_init_f_r_trampoline, @function +board_init_f_r_trampoline: + /* + * SPL has been executed and SDRAM has been initialised, U-Boot code + * has been copied into RAM, BSS has been cleared and relocation + * adjustments have been made. It is now time to jump into the in-RAM + * copy of U-Boot + * + * %eax = Address of top of new stack + */ + + /* Stack grows down from top of SDRAM */ + movl %eax, %esp + + /* Re-enter U-Boot by calling board_init_f_r() */ + call board_init_f_r + +die: + hlt + jmp die + hlt + + .align 4 +_dt_ucode_base_size: + /* These next two fields are filled in by binman */ +.globl ucode_base +ucode_base: /* Declared in microcode.h */ + .long 0 /* microcode base */ +.globl ucode_size +ucode_size: /* Declared in microcode.h */ + .long 0 /* microcode size */ diff --git a/arch/x86/cpu/start_from_tpl.S b/arch/x86/cpu/start_from_tpl.S new file mode 100644 index 00000000000..44b5363a685 --- /dev/null +++ b/arch/x86/cpu/start_from_tpl.S @@ -0,0 +1,49 @@ +/* SPDX-License-Identifier: GPL-2.0+ */ +/* + * 32-bit x86 Startup Code when running from TPL + * + * Copyright 2018 Google, Inc + * Written by Simon Glass sjg@chromium.org + */ + +#include <config.h> + +.section .text.start +.code32 +.globl _start +.type _start, @function +_start: + /* Set up memory using the existing stack */ + mov %esp, %eax + call board_init_f_alloc_reserve + mov %eax, %esp + + call board_init_f_init_reserve + + xorl %eax, %eax + call board_init_f + call board_init_f_r + + /* Should not return here */ + jmp . + +.globl board_init_f_r_trampoline +.type board_init_f_r_trampoline, @function +board_init_f_r_trampoline: + /* + * TPL has been executed: SDRAM has been initialised, BSS has been + * cleared. + * + * %eax = Address of top of new stack + */ + + /* Stack grows down from top of SDRAM */ + movl %eax, %esp + + /* Re-enter SPL by calling board_init_f_r() */ + call board_init_f_r + +die: + hlt + jmp die + hlt