[U-Boot] [PATCH v2 4/7] arc: clean-up init procedure
Alexey Brodkin
Alexey.Brodkin at synopsys.com
Tue Mar 31 12:08:53 CEST 2015
Intention behind this work was elimination of as much assembly-written
code as it is possible.
In case of ARC we already have relocation fix-up implemented in C so why
don't we use C for U-Boot copying, .bss zeroing etc.
It turned out x86 uses pretty similar approach so we re-used parts of
code in "board_f.c" initially implemented for x86.
Now assembly usage during init is limited to stack- and frame-pointer
setup before and after relocation.
Signed-off-by: Alexey Brodkin <abrodkin at synopsys.com>
Cc: Simon Glass <sjg at chromium.org>
---
Changes in v2:
* Unconditionally disable caches on early start
* Only enable caches in init_cache_f_r() because all
caches were disabled earlier
---
arch/arc/include/asm/init_helpers.h | 12 ++++++
arch/arc/include/asm/relocate.h | 16 ++++++++
arch/arc/include/asm/u-boot-arc.h | 3 ++
arch/arc/lib/Makefile | 1 +
arch/arc/lib/cpu.c | 13 ------
arch/arc/lib/init_helpers.c | 25 +++++++++++
arch/arc/lib/relocate.c | 19 +++++++++
arch/arc/lib/start.S | 82 ++++++++-----------------------------
common/board_f.c | 8 ++--
9 files changed, 98 insertions(+), 81 deletions(-)
create mode 100644 arch/arc/include/asm/init_helpers.h
create mode 100644 arch/arc/include/asm/relocate.h
create mode 100644 arch/arc/lib/init_helpers.c
diff --git a/arch/arc/include/asm/init_helpers.h b/arch/arc/include/asm/init_helpers.h
new file mode 100644
index 0000000..7607e19
--- /dev/null
+++ b/arch/arc/include/asm/init_helpers.h
@@ -0,0 +1,12 @@
+/*
+ * Copyright (C) 2013-2015 Synopsys, Inc. All rights reserved.
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#ifndef _ASM_ARC_INIT_HELPERS_H
+#define _ASM_ARC_INIT_HELPERS_H
+
+int init_cache_f_r(void);
+
+#endif /* _ASM_ARC_INIT_HELPERS_H */
diff --git a/arch/arc/include/asm/relocate.h b/arch/arc/include/asm/relocate.h
new file mode 100644
index 0000000..4c5f923
--- /dev/null
+++ b/arch/arc/include/asm/relocate.h
@@ -0,0 +1,16 @@
+/*
+ * Copyright (C) 2013-2015 Synopsys, Inc. All rights reserved.
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#ifndef _ASM_ARC_RELOCATE_H
+#define _ASM_ARC_RELOCATE_H
+
+#include <common.h>
+
+int copy_uboot_to_ram(void);
+int clear_bss(void);
+int do_elf_reloc_fixups(void);
+
+#endif /* _ASM_ARC_RELOCATE_H */
diff --git a/arch/arc/include/asm/u-boot-arc.h b/arch/arc/include/asm/u-boot-arc.h
index 0c0e8e6..a56ccf1 100644
--- a/arch/arc/include/asm/u-boot-arc.h
+++ b/arch/arc/include/asm/u-boot-arc.h
@@ -9,4 +9,7 @@
int arch_early_init_r(void);
+void board_init_f_r_trampoline(ulong) __attribute__ ((noreturn));
+void board_init_f_r(void) __attribute__ ((noreturn));
+
#endif /* __ASM_ARC_U_BOOT_ARC_H__ */
diff --git a/arch/arc/lib/Makefile b/arch/arc/lib/Makefile
index b1f1fbe..b887904 100644
--- a/arch/arc/lib/Makefile
+++ b/arch/arc/lib/Makefile
@@ -20,6 +20,7 @@ obj-y += reset.o
obj-y += timer.o
obj-y += start.o
obj-y += ints_low.o
+obj-y += init_helpers.o
obj-$(CONFIG_CMD_BOOTM) += bootm.o
diff --git a/arch/arc/lib/cpu.c b/arch/arc/lib/cpu.c
index 50634b8..3c930bc 100644
--- a/arch/arc/lib/cpu.c
+++ b/arch/arc/lib/cpu.c
@@ -12,19 +12,6 @@ DECLARE_GLOBAL_DATA_PTR;
int arch_cpu_init(void)
{
-#ifdef CONFIG_SYS_ICACHE_OFF
- icache_disable();
-#else
- icache_enable();
- invalidate_icache_all();
-#endif
-
- flush_dcache_all();
-#ifdef CONFIG_SYS_DCACHE_OFF
- dcache_disable();
-#else
- dcache_enable();
-#endif
timer_init();
/* In simulation (ISS) "CHIPID" and "ARCNUM" are all "ff" */
diff --git a/arch/arc/lib/init_helpers.c b/arch/arc/lib/init_helpers.c
new file mode 100644
index 0000000..25690ee
--- /dev/null
+++ b/arch/arc/lib/init_helpers.c
@@ -0,0 +1,25 @@
+/*
+ * Copyright (C) 2013-2015 Synopsys, Inc. All rights reserved.
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#include <common.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+int init_cache_f_r(void)
+{
+#ifndef CONFIG_SYS_ICACHE_OFF
+ icache_enable();
+ /* Make sure no stale entries persist from before we disabled cache */
+ invalidate_icache_all();
+#endif
+
+#ifndef CONFIG_SYS_DCACHE_OFF
+ dcache_enable();
+ /* Make sure no stale entries persist from before we disabled cache */
+ invalidate_dcache_all();
+#endif
+ return 0;
+}
diff --git a/arch/arc/lib/relocate.c b/arch/arc/lib/relocate.c
index 7797782..5c2c2d1 100644
--- a/arch/arc/lib/relocate.c
+++ b/arch/arc/lib/relocate.c
@@ -10,6 +10,25 @@
DECLARE_GLOBAL_DATA_PTR;
+int copy_uboot_to_ram(void)
+{
+ size_t len = (size_t)&__image_copy_end - (size_t)&__image_copy_start;
+
+ memcpy((void *)gd->relocaddr, (void *)&__image_copy_start, len);
+
+ return 0;
+}
+
+int clear_bss(void)
+{
+ ulong dst_addr = (ulong)&__bss_start + gd->reloc_off;
+ size_t len = (size_t)&__bss_end - (size_t)&__bss_start;
+
+ memset((void *)dst_addr, 0x00, len);
+
+ return 0;
+}
+
/*
* Base functionality is taken from x86 version with added ARC-specifics
*/
diff --git a/arch/arc/lib/start.S b/arch/arc/lib/start.S
index 3408f45..82045ae 100644
--- a/arch/arc/lib/start.S
+++ b/arch/arc/lib/start.S
@@ -13,17 +13,14 @@ ENTRY(_start)
/* Setup interrupt vector base that matches "__text_start" */
sr __ivt_start, [ARC_AUX_INTR_VEC_BASE]
- /* Setup stack pointer */
+ /* Setup stack- and frame-pointers */
mov %sp, CONFIG_SYS_INIT_SP_ADDR
mov %fp, %sp
- /* Clear bss */
- mov %r0, __bss_start
- mov %r1, __bss_end
-
-clear_bss:
- st.ab 0, [%r0, 4]
- brlt %r0, %r1, clear_bss
+ /* Unconditionally disable caches */
+ bl flush_dcache_all
+ bl dcache_disable
+ bl icache_disable
/* Zero the one and only argument of "board_init_f" */
mov_s %r0, 0
@@ -31,67 +28,24 @@ clear_bss:
ENDPROC(_start)
/*
- * void relocate_code (addr_sp, gd, addr_moni)
+ * void board_init_f_r_trampoline(stack-pointer address)
*
* This "function" does not return, instead it continues in RAM
* after relocating the monitor code.
*
- * r0 = start_addr_sp
- * r1 = new__gd
- * r2 = relocaddr
+ * r0 = new stack-pointer
*/
-ENTRY(relocate_code)
- /*
- * r0-r12 might be clobbered by C functions
- * so we use r13-r16 for storage here
- */
- mov %r13, %r0 /* save addr_sp */
- mov %r14, %r1 /* save addr of gd */
- mov %r15, %r2 /* save addr of destination */
-
- mov %r16, %r2 /* %r9 - relocation offset */
- sub %r16, %r16, __image_copy_start
-
-/* Set up the stack */
-stack_setup:
- mov %sp, %r13
+ENTRY(board_init_f_r_trampoline)
+ /* Set up the stack- and frame-pointers */
+ mov %sp, %r0
mov %fp, %sp
-/* Check if monitor is loaded right in place for relocation */
- mov %r0, __image_copy_start
- cmp %r0, %r15 /* skip relocation if code loaded */
- bz do_board_init_r /* in target location already */
-
-/* Copy data (__image_copy_start - __image_copy_end) to new location */
- mov %r1, %r15
- mov %r2, __image_copy_end
- sub %r2, %r2, %r0 /* r3 <- amount of bytes to copy */
- asr %r2, %r2, 2 /* r3 <- amount of words to copy */
- mov %lp_count, %r2
- lp copy_end
- ld.ab %r2,[%r0,4]
- st.ab %r2,[%r1,4]
-copy_end:
-
-/* Fix relocations related issues */
- bl do_elf_reloc_fixups
-#ifndef CONFIG_SYS_ICACHE_OFF
- bl invalidate_icache_all
-#endif
-#ifndef CONFIG_SYS_DCACHE_OFF
- bl flush_dcache_all
-#endif
-
-/* Update position of intterupt vector table */
- lr %r0, [ARC_AUX_INTR_VEC_BASE] /* Read current position */
- add %r0, %r0, %r16 /* Update address */
- sr %r0, [ARC_AUX_INTR_VEC_BASE] /* Write new position */
+ /* Update position of intterupt vector table */
+ lr %r0, [ARC_AUX_INTR_VEC_BASE]
+ ld %r1, [%r25, GD_RELOC_OFF]
+ add %r0, %r0, %r1
+ sr %r0, [ARC_AUX_INTR_VEC_BASE]
-do_board_init_r:
-/* Prepare for exection of "board_init_r" in relocated monitor */
- mov %r2, board_init_r /* old address of "board_init_r()" */
- add %r2, %r2, %r16 /* new address of "board_init_r()" */
- mov %r0, %r14 /* 1-st parameter: gd_t */
- mov %r1, %r15 /* 2-nd parameter: dest_addr */
- j [%r2]
-ENDPROC(relocate_code)
+ /* Re-enter U-Boot by calling board_init_f_r */
+ j board_init_f_r
+ENDPROC(board_init_f_r_trampoline)
diff --git a/common/board_f.c b/common/board_f.c
index f7ffa54..cb956b8 100644
--- a/common/board_f.c
+++ b/common/board_f.c
@@ -47,7 +47,7 @@
#include <asm/errno.h>
#include <asm/io.h>
#include <asm/sections.h>
-#ifdef CONFIG_X86
+#if defined(CONFIG_X86) || defined(CONFIG_ARC)
#include <asm/init_helpers.h>
#include <asm/relocate.h>
#endif
@@ -761,7 +761,7 @@ static int jump_to_copy(void)
* similarly for all archs. When we do generic relocation, hopefully
* we can make all archs enable the dcache prior to relocation.
*/
-#ifdef CONFIG_X86
+#if defined(CONFIG_X86) || defined(CONFIG_ARC)
/*
* SDRAM and console are now initialised. The final stack can now
* be setup in SDRAM. Code execution will continue in Flash, but
@@ -997,7 +997,7 @@ static init_fnc_t init_sequence_f[] = {
INIT_FUNC_WATCHDOG_RESET
reloc_fdt,
setup_reloc,
-#ifdef CONFIG_X86
+#if defined(CONFIG_X86) || defined(CONFIG_ARC)
copy_uboot_to_ram,
clear_bss,
do_elf_reloc_fixups,
@@ -1041,7 +1041,7 @@ void board_init_f(ulong boot_flags)
#endif
}
-#ifdef CONFIG_X86
+#if defined(CONFIG_X86) || defined(CONFIG_ARC)
/*
* For now this code is only used on x86.
*
--
2.1.0
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