arc: clean-up init procedure

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@synopsys.com>
Cc: Simon Glass <sjg@chromium.org>

diff --git a/arch/arc/include/asm/init_helpers.h b/arch/arc/include/asm/init_helpers.h
new file mode 100644 (file)
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 (file)
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 0c0e8e661dddd8ff5cccdc09613c28852c0e0801..a56ccf1b5d38c865ccea93869c2de355e6240384 100644 (file)
--- 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 b1f1fbe4a1bd29be254952e6ba50a25d3faaa5c4..b88790492d2a2805819905a667430a5d807bcc7d 100644 (file)
--- 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 50634b860f79580011b4701e3ff051cb1ec97c7c..3c930bcbebd929a2546a74b2939ac5603160a2c1 100644 (file)
--- 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 (file)
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 7797782563bb7f6dc736440fa6fa7aa0818a9e5a..5c2c2d19309b184ad9b62798cc667057c2fa216b 100644 (file)
--- 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 3408f45d2ca8080877028cad3f8936eaf7b7011c..82045aeb6dd5a5e0b739e4eae6e5a107dbba0745 100644 (file)
--- 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 f7ffa54052bafb34979ced6c0254423a07b38b63..cb956b853c5ca825d962cdda205239caf5b14d7e 100644 (file)
--- 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.
  *