arm: Tidy up early init

Unfortunately memset() is not always available, so provide a substitute when needed.

Signed-off-by Simon Glass <[email protected]>

---

Changes in v3: None
Changes in v2:
- Add comments as to why this is needed, deal with arch-specific memset()

 common/init/board_init.c | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

common/init/board_init.c +13 -0

index e7ebca7..c113a80 100644
@@ -11,6 +11,16 @@
 
 DECLARE_GLOBAL_DATA_PTR;
 
+/*
+ * It isn't trivial to figure out whether memcpy() exists. The arch-specific
+ * memcpy() is not normally available in SPL due to code size.
+ */
+#if !defined(CONFIG_SPL_BUILD) || \
+		(defined(CONFIG_SPL_LIBGENERIC_SUPPORT) && \
+		!defined(CONFIG_USE_ARCH_MEMSET))
+#define _USE_MEMCPY
+#endif
+
 /* Unfortunately x86 can't compile this code as gd cannot be assigned */
 #ifndef CONFIG_X86
 __weak void arch_setup_gd(struct global_data *gd_ptr)

@@ -22,6 +32,9 @@ __weak void arch_setup_gd(struct global_data *gd_ptr)
 ulong board_init_f_mem(ulong top)
 {
 	struct global_data *gd_ptr;
+#ifndef _USE_MEMCPY
+	int *ptr, *end;
+#endif
 
 	/* Leave space for the stack we are running with now */
 	top -= 0x40;

common/init/board_init.c +2 -0

+		*ptr++ = 0;
+#endif
 	arch_setup_gd(gd_ptr);
 
 #if defined(CONFIG_SYS_MALLOC_F)

Signature · 1 line

2.6.0.rc2.230.g3dd15c0

Hello Simon,

Quoted 42 lines · Simon Glass

Unfortunately memset() is not always available, so provide a substitute when needed.

Signed-off-by Simon Glass <[email protected]>

---

Changes in v3: None
Changes in v2:
- Add comments as to why this is needed, deal with arch-specific memset()

 common/init/board_init.c | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

common/init/board_init.c +13 -0

index e7ebca7..c113a80 100644
@@ -11,6 +11,16 @@
 
 DECLARE_GLOBAL_DATA_PTR;
 
+/*
+ * It isn't trivial to figure out whether memcpy() exists. The arch-specific
+ * memcpy() is not normally available in SPL due to code size.
+ */
+#if !defined(CONFIG_SPL_BUILD) || \
+             (defined(CONFIG_SPL_LIBGENERIC_SUPPORT) && \
+             !defined(CONFIG_USE_ARCH_MEMSET))
+#define _USE_MEMCPY
+#endif
+
 /* Unfortunately x86 can't compile this code as gd cannot be assigned */
 #ifndef CONFIG_X86
 __weak void arch_setup_gd(struct global_data *gd_ptr)

@@ -22,6 +32,9 @@ __weak void arch_setup_gd(struct global_data *gd_ptr)
 ulong board_init_f_mem(ulong top)
 {
      struct global_data *gd_ptr;
+#ifndef _USE_MEMCPY
+     int *ptr, *end;
+#endif
 

common/init/board_init.c ulong board_init_f_mem(ulong top) · line 48

Quoted 10 lines

common/init/board_init.c +3 -0

      /* Leave space for the stack we are running with now */
      top -= 0x40;

@@ -29,7 +42,12 @@ ulong board_init_f_mem(ulong top)
      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, end = (int *)(gd_ptr + 1); ptr < end; )

Nitpick here: There is little point in naming a variable just for it to be set and used once. Without 'end', the compiler will be just as fine if ptr is directly tested against (int *)(gd_ptr + 1), and human readers won't wonder why 'end' was created.

Quoted 5 lines

common/init/board_init.c +2 -0

+             *ptr++ = 0;
+#endif
      arch_setup_gd(gd_ptr);
 

Quoted 3 lines

common/init/board_init.c +0 -1

 #if defined(CONFIG_SYS_MALLOC_F)
--

2.6.0.rc2.230.g3dd15c0

Amicalement,
--
Albert.

Hi Albert,

Quoted 46 lines · Albert ARIBAUD

Hello Simon,

Quoted 42 lines · Simon Glass

Unfortunately memset() is not always available, so provide a substitute when needed.

Signed-off-by Simon Glass <[email protected]>

---

Changes in v3: None
Changes in v2:
- Add comments as to why this is needed, deal with arch-specific memset()

 common/init/board_init.c | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

common/init/board_init.c +13 -0

index e7ebca7..c113a80 100644
@@ -11,6 +11,16 @@
 
 DECLARE_GLOBAL_DATA_PTR;
 
+/*
+ * It isn't trivial to figure out whether memcpy() exists. The arch-specific
+ * memcpy() is not normally available in SPL due to code size.
+ */
+#if !defined(CONFIG_SPL_BUILD) || \
+             (defined(CONFIG_SPL_LIBGENERIC_SUPPORT) && \
+             !defined(CONFIG_USE_ARCH_MEMSET))
+#define _USE_MEMCPY
+#endif
+
 /* Unfortunately x86 can't compile this code as gd cannot be assigned */
 #ifndef CONFIG_X86
 __weak void arch_setup_gd(struct global_data *gd_ptr)

@@ -22,6 +32,9 @@ __weak void arch_setup_gd(struct global_data *gd_ptr)
 ulong board_init_f_mem(ulong top)
 {
      struct global_data *gd_ptr;
+#ifndef _USE_MEMCPY
+     int *ptr, *end;
+#endif
 

Quoted 15 lines

common/init/board_init.c ulong board_init_f_mem(ulong top) · line 48

Quoted 10 lines

common/init/board_init.c +3 -0

      /* Leave space for the stack we are running with now */
      top -= 0x40;

@@ -29,7 +42,12 @@ ulong board_init_f_mem(ulong top)
      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, end = (int *)(gd_ptr + 1); ptr < end; )

Nitpick here: There is little point in naming a variable just for it to be set and used once. Without 'end', the compiler will be just as fine if ptr is directly tested against (int *)(gd_ptr + 1), and human readers won't wonder why 'end' was created.

Well it makes it clear that the ptr goes from the start to the end. But it's probably clear enough just doing what you suggest, so I can change it.

We should not init the console this early and there is no need to. If we want to do early init it can be done in spl_board_init(). Move the preloader_console_init() call from board_init_f() to board_init_r().

Signed-off-by Simon Glass <[email protected]>

Tested-by Masahiro Yamada <[email protected]>

Tested-by Michal Simek <[email protected]>

Hello Simon,

Quoted 4 lines · Simon Glass

We should not init the console this early and there is no need to. If we want to do early init it can be done in spl_board_init(). Move the preloader_console_init() call from board_init_f() to board_init_r().

Quoted 3 lines

Signed-off-by Simon Glass <[email protected]>

Tested-by Masahiro Yamada <[email protected]>

Tested-by Michal Simek <[email protected]>

I personally think that we should, almost must in fact, initialize the console as early as possible.

What exactly is the drawaback of initializing the console here?

Hi Albert,

Quoted 12 lines · Albert ARIBAUD

Hello Simon,

Quoted 7 lines · Simon Glass

We should not init the console this early and there is no need to. If we want to do early init it can be done in spl_board_init(). Move the preloader_console_init() call from board_init_f() to board_init_r().

Signed-off-by Simon Glass <[email protected]>

Tested-by Masahiro Yamada <[email protected]>

Tested-by Michal Simek <[email protected]>

Quoted 4 lines

I personally think that we should, almost must in fact, initialize the console as early as possible.

What exactly is the drawaback of initializing the console here?

This is described in the README now for SPL. The console is not available until driver model is ready, which cannot be before global_data is ready.

My second zynq series removes the next few lines from board_init_f(), so in effect there is very little difference in timing - the console still is set up very early. It is just that we must not set it up before driver model is running.

There is also a debug UART which can be used to make printf() work before global_data is available. But I'm trying to remove the global_data hacks that exist in early board code.

Regards,
Simon