diff mbox series

[U-Boot,v2,20/50] x86: Add support for starting from SPL/TPL

Message ID 20190426035922.20596-21-sjg@chromium.org
State Accepted
Commit 051c31b7a49933f25bcf2ffe8c7764642fcff0d4
Delegated to: Bin Meng
Headers show
Series x86: Add support for booting from TPL | expand

Commit Message

Simon Glass April 26, 2019, 3:58 a.m. UTC 
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

Comments

Bin Meng May 1, 2019, 1:03 p.m. UTC | #1 
On Fri, Apr 26, 2019 at 12:00 PM Simon Glass <sjg@chromium.org> wrote:
>
> 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
>

Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Bin Meng May 1, 2019, 3:25 p.m. UTC | #2 
On Wed, May 1, 2019 at 9:03 PM Bin Meng <bmeng.cn@gmail.com> wrote:
>
> On Fri, Apr 26, 2019 at 12:00 PM Simon Glass <sjg@chromium.org> wrote:
> >
> > 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
> >
>
> Reviewed-by: Bin Meng <bmeng.cn@gmail.com>

applied to u-boot-x86, thanks!
diff mbox series

Patch

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