[U-Boot] [PATCH v2] Fix board init code to use a valid C runtime environment

Albert ARIBAUD
2015-11-10T18:30:47Z

board_init_f_mem() alters the C runtime environment's
stack it ls actually already using. This is not a valid
C runtime environment.

Split board_init_f_mem into C functions which do not
alter their own stack and therefore run in a valid C
runtime environment.

Signed-off-by: Albert ARIBAUD <albert.u.boot@aribaud.net>
---
For NIOS2, this patch hopefully contains all manual
fixes by Thomas.

Changes in v2:
- Fix all checkpatch issues
- Fix board_init_f_malloc prototype mismatch
- Fix board_init_[f_]xxx typo in NIOS2
- Fix aarch64 asm 'sub' syntax error

arch/arc/lib/start.S | 20 +++++++++++++---
arch/arm/lib/crt0.S | 10 ++++++--
arch/arm/lib/crt0_64.S | 10 ++++++--
arch/microblaze/cpu/start.S | 4 ++--
arch/nios2/cpu/start.S | 17 ++++++++++++--
arch/powerpc/cpu/ppc4xx/start.S | 18 ++++++++++----
arch/x86/cpu/start.S | 10 ++++++--
arch/x86/lib/fsp/fsp_common.c | 4 ++--
common/init/board_init.c | 31 ++++++++++++++----------
include/common.h | 52 +++++++++++++++++++++++++----------------
10 files changed, 125 insertions(+), 51 deletions(-)

diff --git a/arch/arc/lib/start.S b/arch/arc/lib/start.S
index 26a5934..d24d60b 100644
--- a/arch/arc/lib/start.S
+++ b/arch/arc/lib/start.S
@@ -54,14 +54,28 @@ ENTRY(_start)
mov %sp, CONFIG_SYS_INIT_SP_ADDR
mov %fp, %sp

- /* Allocate and zero GD, update SP */
+ /* Allocate GD, update SP */
mov %r0, %sp
- bl board_init_f_mem
+ bl board_init_f_gd_size
+ /* Update stack- and frame-pointers */
+ sub %sp, %sp, %r0
+ mov %fp, %sp
+
+ /* Zero GD */
+ mov %r0, %sp
+ bl board_init_f_gd

+ /* Allocate malloc, update SP */
+ mov %r0, %sp
+ bl board_init_f_malloc_size
/* Update stack- and frame-pointers */
- mov %sp, %r0
+ sub %sp, %sp, %r0
mov %fp, %sp

+ /* update GD with malloc base */
+ mov %r0, %sp
+ bl board_init_f_malloc
+
/* Zero the one and only argument of "board_init_f" */
mov_s %r0, 0
j board_init_f
diff --git a/arch/arm/lib/crt0.S b/arch/arm/lib/crt0.S
index 80548eb..26abab7 100644
--- a/arch/arm/lib/crt0.S
+++ b/arch/arm/lib/crt0.S
@@ -82,9 +82,15 @@ ENTRY(_main)
#else
bic sp, sp, #7 /* 8-byte alignment for ABI compliance */
#endif
+ bl board_init_f_gd_size
+ sub sp, r0
mov r0, sp
- bl board_init_f_mem
- mov sp, r0
+ mov r9, r0
+ bl board_init_f_gd
+ bl board_init_f_malloc_size
+ sub sp, r0
+ mov r0, sp
+ bl board_init_f_malloc

mov r0, #0
bl board_init_f
diff --git a/arch/arm/lib/crt0_64.S b/arch/arm/lib/crt0_64.S
index cef1c71..00cef36 100644
--- a/arch/arm/lib/crt0_64.S
+++ b/arch/arm/lib/crt0_64.S
@@ -75,8 +75,14 @@ ENTRY(_main)
ldr x0, =(CONFIG_SYS_INIT_SP_ADDR)
#endif
bic sp, x0, #0xf /* 16-byte alignment for ABI compliance */
- bl board_init_f_mem
- mov sp, x0
+ bl board_init_f_gd_size
+ sub sp, sp, x0
+ mov x0, sp
+ bl board_init_f_gd
+ bl board_init_f_malloc_size
+ sub sp, sp, x0
+ mov x0, sp
+ bl board_init_f_malloc

mov x0, #0
bl board_init_f
diff --git a/arch/microblaze/cpu/start.S b/arch/microblaze/cpu/start.S
index 14f46a8..206be3e 100644
--- a/arch/microblaze/cpu/start.S
+++ b/arch/microblaze/cpu/start.S
@@ -25,7 +25,7 @@ _start:

addi r8, r0, __end
mts rslr, r8
- /* TODO: Redo this code to call board_init_f_mem() */
+ /* TODO: Redo this code to call board_init_f_*() */
#if defined(CONFIG_SPL_BUILD)
addi r1, r0, CONFIG_SPL_STACK_ADDR
mts rshr, r1
@@ -142,7 +142,7 @@ _start:
ori r12, r12, 0x1a0
mts rmsr, r12

- /* TODO: Redo this code to call board_init_f_mem() */
+ /* TODO: Redo this code to call board_init_f_*() */
clear_bss:
/* clear BSS segments */
addi r5, r0, __bss_start
diff --git a/arch/nios2/cpu/start.S b/arch/nios2/cpu/start.S
index 54787c5..c163ce1 100644
--- a/arch/nios2/cpu/start.S
+++ b/arch/nios2/cpu/start.S
@@ -107,9 +107,22 @@ _reloc:
mov fp, sp

/* Allocate and zero GD, update SP */
+ movhi r2, %hi(board_init_f_gd_size at h)
+ ori r2, r2, %lo(board_init_f_gd_size at h)
+ callr r2
+ sub sp, sp, r4
+ mov r4, sp
+ movhi r2, %hi(board_init_f_gd at h)
+ ori r2, r2, %lo(board_init_f_gd at h)
+ callr r2
+ /* Allocate malloc arena, update SP */
+ movhi r2, %hi(board_init_f_malloc_size at h)
+ ori r2, r2, %lo(board_init_f_malloc_size at h)
+ callr r2
+ sub sp, sp, r4
mov r4, sp
- movhi r2, %hi(board_init_f_mem at h)
- ori r2, r2, %lo(board_init_f_mem at h)
+ movhi r2, %hi(board_init_f_malloc at h)
+ ori r2, r2, %lo(board_init_f_malloc at h)
callr r2

/* Update stack- and frame-pointers */
diff --git a/arch/powerpc/cpu/ppc4xx/start.S b/arch/powerpc/cpu/ppc4xx/start.S
index 77d4040..c827c95 100644
--- a/arch/powerpc/cpu/ppc4xx/start.S
+++ b/arch/powerpc/cpu/ppc4xx/start.S
@@ -761,9 +761,14 @@ _start:

bl cpu_init_f /* run low-level CPU init code (from Flash) */
#ifdef CONFIG_SYS_GENERIC_BOARD
+ bl board_init_f_gd_size
+ sub r1, r1, r3
mr r3, r1
- bl board_init_f_mem
- mr r1, r3
+ bl board_init_f_gd
+ bl board_init_f_malloc_size
+ sub r1, r1, r3
+ mr r3, r1
+ bl board_init_f_malloc
li r0,0
stwu r0, -4(r1)
stwu r0, -4(r1)
@@ -1037,9 +1042,14 @@ _start:

bl cpu_init_f /* run low-level CPU init code (from Flash) */
#ifdef CONFIG_SYS_GENERIC_BOARD
+ bl board_init_f_gd_size
+ sub r1, r1, r3
+ mr r3, r1
+ bl board_init_f_gd
+ bl board_init_f_malloc_size
+ sub r1, r1, r3
mr r3, r1
- bl board_init_f_mem
- mr r1, r3
+ bl board_init_f_malloc
stwu r0, -4(r1)
stwu r0, -4(r1)
#endif
diff --git a/arch/x86/cpu/start.S b/arch/x86/cpu/start.S
index 5b4ee79..25ac286 100644
--- a/arch/x86/cpu/start.S
+++ b/arch/x86/cpu/start.S
@@ -122,9 +122,15 @@ car_init_ret:
*/
#endif
/* Set up global data */
+ call board_init_f_gd_size
+ subl %esp, %eax
mov %esp, %eax
- call board_init_f_mem
- mov %eax, %esp
+ call board_init_f_gd
+ /* Set up malloc arena */
+ call board_init_f_malloc_size
+ subl %esp, %eax
+ mov %esp, %eax
+ call board_init_f_malloc

#ifdef CONFIG_DEBUG_UART
call debug_uart_init
diff --git a/arch/x86/lib/fsp/fsp_common.c b/arch/x86/lib/fsp/fsp_common.c
index c78df94..5249455 100644
--- a/arch/x86/lib/fsp/fsp_common.c
+++ b/arch/x86/lib/fsp/fsp_common.c
@@ -95,8 +95,8 @@ int x86_fsp_init(void)
/*
* The second time we enter here, adjust the size of malloc()
* pool before relocation. Given gd->malloc_base was adjusted
- * after the call to board_init_f_mem() in arch/x86/cpu/start.S,
- * we should fix up gd->malloc_limit here.
+ * after the call to board_init_f_malloc() in arch/x86/cpu/
+ * start.S, we should fix up gd->malloc_limit here.
*/
gd->malloc_limit += CONFIG_FSP_SYS_MALLOC_F_LEN;
}
diff --git a/common/init/board_init.c b/common/init/board_init.c
index e74b63b..8839a4a 100644
--- a/common/init/board_init.c
+++ b/common/init/board_init.c
@@ -29,32 +29,39 @@ __weak void arch_setup_gd(struct global_data *gd_ptr)
}
#endif /* !CONFIG_X86 */

-ulong board_init_f_mem(ulong top)
+ulong board_init_f_gd_size(void)
+{
+ return roundup(sizeof(struct global_data), 16);
+}
+
+void board_init_f_gd(struct global_data *gd_ptr)
{
- struct global_data *gd_ptr;
#ifndef _USE_MEMCPY
int *ptr;
#endif

- /* Leave space for the stack we are running with now */
- top -= 0x40;
-
- top -= sizeof(struct global_data);
- top = ALIGN(top, 16);
- gd_ptr = (struct global_data *)top;
#ifdef _USE_MEMCPY
memset(gd_ptr, '\0', sizeof(*gd));
#else
for (ptr = (int *)gd_ptr; ptr < (int *)(gd_ptr + 1); )
*ptr++ = 0;
#endif
- arch_setup_gd(gd_ptr);
+}

+ulong board_init_f_malloc_size(void)
+{
#if defined(CONFIG_SYS_MALLOC_F) && \
(!defined(CONFIG_SPL_BUILD) || !defined(CONFIG_SYS_SPL_MALLOC_START))
- top -= CONFIG_SYS_MALLOC_F_LEN;
- gd->malloc_base = top;
+ return CONFIG_SYS_MALLOC_F_LEN;
+#else
+ return 0;
#endif
+}

- return top;
+void board_init_f_malloc(ulong malloc_base)
+{
+#if defined(CONFIG_SYS_MALLOC_F) && \
+ (!defined(CONFIG_SPL_BUILD) || !defined(CONFIG_SYS_SPL_MALLOC_START))
+ gd->malloc_base = malloc_base;
+#endif
}
diff --git a/include/common.h b/include/common.h
index 09a131d..a2d81d9 100644
--- a/include/common.h
+++ b/include/common.h
@@ -225,32 +225,44 @@ void board_init_f(ulong);
void board_init_r(gd_t *, ulong) __attribute__ ((noreturn));

/**
- * board_init_f_mem() - Allocate global data and set stack position
+ * board_init_f_gd_size() - Return the size of the global data
*
* This function is called by each architecture very early in the start-up
- * code to set up the environment for board_init_f(). It allocates space for
- * global_data (see include/asm-generic/global_data.h) and places the stack
- * below this.
+ * code to allow the C runtime to reserve space for the GD on the stack.
*
- * This function requires a stack[1] Normally this is at @top. The function
- * starts allocating space from 64 bytes below @top. First it creates space
- * for global_data. Then it calls arch_setup_gd() which sets gd to point to
- * the global_data space and can reserve additional bytes of space if
- * required). Finally it allocates early malloc() memory
- * (CONFIG_SYS_MALLOC_F_LEN). The new top of the stack is just below this,
- * and it returned by this function.
+ * @return: GD size
+ */
+ulong board_init_f_gd_size(void);
+
+/**
+ * board_init_f_gd() - Initialize (zero) the global data
+ *
+ * This function is called once the C runtime has allocated the GD on
+ * the stack. It must initialize the GD.
+ *
+ * @gd_ptr: the pointer to the GD to initialize
+ */
+void board_init_f_gd(struct global_data *gd_ptr);
+
+/**
+ * board_init_f_malloc_size() - Return the size of the malloc arena
+ *
+ * This function is called once the GD is initialized, to allow the C
+ * runtime to allocate the malloc arena on the stack.
+ *
+ * @return: Malloc arena size
+ */
+ulong board_init_f_malloc_size(void);
+
+/**
+ * board_init_f_malloc() - Mark the malloc arena base in the global data
*
- * [1] Strictly speaking it would be possible to implement this function
- * in C on many archs such that it does not require a stack. However this
- * does not seem hugely important as only 64 byte are wasted. The 64 bytes
- * are used to handle the calling standard which generally requires pushing
- * addresses or registers onto the stack. We should be able to get away with
- * less if this becomes important.
+ * This function is called once the malloc arena is allocated on the
+ * stack. It marks the malloc arena base in the global data.
*
- * @top: Top of available memory, also normally the top of the stack
- * @return: New stack location
+ * @malloc_base: the base of the malloc arena
*/
-ulong board_init_f_mem(ulong top);
+void board_init_f_malloc(ulong malloc_base);

/**
* arch_setup_gd() - Set up the global_data pointer
--
2.5.0