i386: Final Relocation

Signed-off-by: Graeme Russ <graeme.russ@gmail.com>

board/eNET/config.mk

@@ -23,4 +23,6 @@
 
 TEXT_BASE = 0x38040000
 CFLAGS_dlmalloc.o += -Wa,--no-warn -fno-strict-aliasing
+PLATFORM_RELFLAGS += -fvisibility=hidden
 PLATFORM_CPPFLAGS += -fno-dwarf2-cfi-asm
+PLATFORM_LDFLAGS += -pic --emit-relocs -Bsymbolic -Bsymbolic-functions

board/eNET/eNET.c

@@ -47,7 +47,6 @@ void init_sc520_enet (void)
 {
 	/* Set CPU Speed to 100MHz */
 	sc520_mmcr->cpuctl = 0x01;
-	gd->cpu_clk = 100000000;
 
 	/* wait at least one millisecond */
 	asm("movl	$0x2000,%%ecx\n"
@@ -67,7 +66,7 @@ void init_sc520_enet (void)
 /*
  * Miscellaneous platform dependent initializations
  */
-int board_init(void)
+int board_early_init_f(void)
 {
 	init_sc520_enet();
 
@@ -117,6 +116,14 @@ int board_init(void)
 	sc520_mmcr->sysarbctl = 0x06;
 	sc520_mmcr->sysarbmenb = 0x0003;
 
+	return 0;
+}
+
+int board_early_init_r(void)
+{
+	/* CPU Speed to 100MHz */
+	gd->cpu_clk = 100000000;
+
 	/* Crystal is 33.000MHz */
 	gd->bus_clk = 33000000;
 

board/eNET/u-boot.lds

@@ -28,28 +28,48 @@ ENTRY(_start)
 SECTIONS
 {
 	. = 0x38040000;		/* Location of bootcode in flash */
+	_i386boot_text_start = .;
 	.text  : { *(.text); }
 
 	. = ALIGN(4);
 	.rodata : { *(SORT_BY_ALIGNMENT(SORT_BY_NAME(.rodata*))) }
 
 	_i386boot_text_size = SIZEOF(.text) + SIZEOF(.rodata);
+	. = ALIGN(4);
+
+	.data : { *(.data) }
+	. = ALIGN(4);
+
+	.interp : { *(.interp) }
+	. = ALIGN(4);
+
+	.dynsym : { *(.dynsym) }
+	. = ALIGN(4);
 
-	. = 0x03FF0000;		/* Ram data segment to use */
-	_i386boot_romdata_dest = ABSOLUTE(.);
-	.data : AT ( LOADADDR(.rodata) + SIZEOF(.rodata) ) { *(.data) }
-	_i386boot_romdata_start = LOADADDR(.data);
+	.dynstr : { *(.dynstr) }
+	. = ALIGN(4);
+
+	.hash : { *(.hash) }
+	. = ALIGN(4);
 
+	.got : { *(.got) }
 	. = ALIGN(4);
-	.got : AT ( LOADADDR(.data) + SIZEOF(.data) ) { *(.got) }
 
+	.got.plt : { *(.got.plt) }
 	. = ALIGN(4);
+
+	.dynamic (NOLOAD) : { *(.dynamic) }
+	. = ALIGN(4);
+
 	__u_boot_cmd_start = .;
 	.u_boot_cmd : { *(.u_boot_cmd) }
+	. = ALIGN(4);
 	__u_boot_cmd_end = .;
 	_i386boot_cmd_start = LOADADDR(.u_boot_cmd);
 
-	_i386boot_romdata_size = SIZEOF(.data) + SIZEOF(.got) + SIZEOF(.u_boot_cmd);
+	_i386boot_rel_dyn_start = .;
+	.rel.dyn : { *(.rel.dyn) }
+	_i386boot_rel_dyn_end = .;
 
 	. = ALIGN(4);
 	_i386boot_bss_start = ABSOLUTE(.);
@@ -57,7 +77,7 @@ SECTIONS
 	_i386boot_bss_size = SIZEOF(.bss);
 
 	/* 16bit realmode trampoline code */
-	.realmode 0x7c0 : AT ( LOADADDR(.got) + SIZEOF(.got) + SIZEOF(.u_boot_cmd)) { *(.realmode) }
+	.realmode 0x7c0 : AT ( LOADADDR(.rel.dyn) + SIZEOF(.rel.dyn) ) { *(.realmode) }
 
 	_i386boot_realmode = LOADADDR(.realmode);
 	_i386boot_realmode_size = SIZEOF(.realmode);

cpu/i386/cpu.c

@@ -37,7 +37,7 @@
 #include <command.h>
 #include <asm/interrupt.h>
 
-int cpu_init(void)
+int cpu_init_f(void)
 {
 	/* initialize FPU, reset EM, set MP and NE */
 	asm ("fninit\n" \
@@ -46,9 +46,13 @@ int cpu_init(void)
 	     "orl  $0x22, %eax\n" \
 	     "movl %eax, %cr0\n" );
 
+	return 0;
+}
+
+int cpu_init_r(void)
+{
 	/* Initialize core interrupt and exception functionality of CPU */
 	cpu_init_interrupts ();
-
 	return 0;
 }
 

cpu/i386/interrupts.c

@@ -63,8 +63,8 @@ static inline void load_idt(const struct desc_ptr *dtr)
 
 void set_vector(u8 intnum, void *routine)
 {
-	idt[intnum].base_high = (u16)((u32)(routine + gd->reloc_off) >> 16);
-	idt[intnum].base_low = (u16)((u32)(routine + gd->reloc_off) & 0xffff);
+	idt[intnum].base_high = (u16)((u32)(routine) >> 16);
+	idt[intnum].base_low = (u16)((u32)(routine) & 0xffff);
 }
 
 void irq_0(void);

cpu/i386/start.S

@@ -63,11 +63,8 @@ early_board_init_ret:
 	jmp     mem_init
 mem_init_ret:
 
-	/* check ammount of configured memory
-	 * (we need atleast bss start+bss size+stack size) */
-	movl	$_i386boot_bss_start, %ecx        /* BSS start */
-	addl	$_i386boot_bss_size, %ecx         /* BSS size */
-	addl	$CONFIG_SYS_STACK_SIZE, %ecx
+	/* Check we have enough memory for stack */
+	movl	$CONFIG_SYS_STACK_SIZE, %ecx
 	cmpl	%ecx, %eax
 	jae	mem_ok
 
@@ -78,6 +75,8 @@ mem_init_ret:
 .progress0a:
 	jmp	die
 mem_ok:
+	/* Set stack pointer to upper memory limit*/
+	movl    %eax, %esp
 
 	/* indicate progress */
 	movw	$0x02, %ax
@@ -85,12 +84,7 @@ mem_ok:
 	jmp	show_boot_progress_asm
 .progress1:
 
-	/* create a stack after the bss */
-	movl    $_i386boot_bss_start, %eax
-	addl	$_i386boot_bss_size, %eax
-	addl	$CONFIG_SYS_STACK_SIZE, %eax
-	movl    %eax, %esp
-
+	/* Test the stack */
 	pushl	$0
 	popl	%eax
 	cmpl	$0, %eax
@@ -116,115 +110,19 @@ stack_ok:
 	jmp	show_boot_progress_asm
 .progress2:
 
-	/* copy data section to ram, size must be 4-byte aligned */
-	movl	$_i386boot_romdata_dest, %edi	  /* destination address */
-	movl	$_i386boot_romdata_start, %esi	  /* source address */
-	movl	$_i386boot_romdata_size, %ecx     /* number of bytes to copy */
-	movl	%ecx, %eax
-	andl	$3, %eax
-	jnz	data_fail
-
-	shrl	$2, %ecx	                  /* copy 4 byte each time */
-	cld
-	cmpl	$0, %ecx
-	je	data_ok
-data_segment:
-	movsl
-	loop	data_segment
-	jmp	data_ok
-data_fail:
-	/* indicate (lack of) progress */
-	movw	$0x83, %ax
-	movl	$.progress2a, %ebp
-	jmp	show_boot_progress_asm
-.progress2a:
-	jmp	die
-
-data_ok:
-
-	/* indicate progress */
-	movw	$0x04, %ax
-	movl	$.progress3, %ebp
-	jmp	show_boot_progress_asm
-.progress3:
-
-	/* clear bss section in ram, size must be 4-byte aligned  */
-	movl	$_i386boot_bss_start, %edi        /* MK_CHG BSS start */
-	movl	$_i386boot_bss_size, %ecx         /* BSS size */
-	movl	%ecx, %eax
-	andl	$3, %eax
-	jnz	bss_fail
-	shrl	$2, %ecx	                  /* clear 4 byte each time */
-	cld
-	cmpl	$0, %ecx
-	je	bss_ok
-bss:
-	movl	$0, (%edi)
-	add	$4, %edi
-	loop	bss
-	jmp	bss_ok
-
-bss_fail:
-	/* indicate (lack of) progress */
-	movw	$0x84, %ax
-	movl	$.progress3a, %ebp
-	jmp	show_boot_progress_asm
-.progress3a:
-	jmp	die
-
-bss_ok:
-#ifndef CONFIG_SKIP_RELOCATE_UBOOT
-	/* indicate progress */
-	movw	$0x06, %ax
-	movl	$.progress6, %ebp
-	jmp	show_boot_progress_asm
-.progress6:
-
-	/* copy text section to ram, size must be 4-byte aligned */
-	movl	$CONFIG_SYS_BL_START_RAM, %edi		/* destination address */
-	movl	$TEXT_BASE, %esi		/* source address */
-	movl	$_i386boot_text_size, %ecx	/* number of bytes to copy */
-	movl	%ecx, %eax
-	andl	$3, %eax
-	jz	text_copy			/* Already 4-byte aligned */
-	subl    $4, %eax			/* Add extra bytes to size */
-	addl	%eax, %ecx
-text_copy:
-	shrl	$2, %ecx			/* copy 4 byte each time */
-	cld
-	cmpl	$0, %ecx
-	je	text_ok
-text_segment:
-	movsl
-	loop	text_segment
-	jmp	text_ok
-text_fail:
-	/* indicate (lack of) progress */
-	movw	$0x86, %ax
-	movl	$.progress5a, %ebp
-	jmp	show_boot_progress_asm
-.progress5a:
-	jmp	die
-
-text_ok:
-#endif
 	wbinvd
 
+	/* Get upper memory limit */
+	movl %esp, %ecx
+	subl $CONFIG_SYS_STACK_SIZE, %ecx
 
-	/* indicate progress */
-	movw	$0x05, %ax
-	movl	$.progress4, %ebp
-	jmp	show_boot_progress_asm
-.progress4:
-
-#ifndef CONFIG_SKIP_RELOCATE_UBOOT
-	/* Jump to the RAM copy of start_i386boot */
-	movl	$start_i386boot, %ebp
-	addl	$(CONFIG_SYS_BL_START_RAM - TEXT_BASE), %ebp
-	call	*%ebp		/* Enter, U-boot! */
-#else
-	call	start_i386boot  /* Enter, U-boot! */
-#endif
+	/* Create a Stack Frame */
+	pushl %ebp
+	movl %esp, %ebp
+
+	/* stack_limit parameter */
+	pushl	%ecx
+	call	board_init_f	/* Enter, U-boot! */
 
 	/* indicate (lack of) progress */
 	movw	$0x85, %ax

include/asm-i386/u-boot-i386.h

@@ -24,19 +24,9 @@
 #ifndef _U_BOOT_I386_H_
 #define _U_BOOT_I386_H_	1
 
-/* for the following variables, see start.S */
-extern ulong i386boot_start;	    /* code start (in flash) */
-extern ulong i386boot_end;	    /* code end (in flash) */
-extern ulong i386boot_romdata_start;/* datasegment in flash (also code+rodata end) */
-extern ulong i386boot_romdata_dest; /* data location segment in ram */
-extern ulong i386boot_romdata_size; /* size of data segment */
-extern ulong i386boot_bss_start;    /* bss start */
-extern ulong i386boot_bss_size;     /* bss size */
-extern ulong i386boot_stack_end;    /* first usable RAM address after bss and stack */
-extern ulong i386boot_ram_end;      /* end of ram */
-
 /* cpu/.../cpu.c */
-int cpu_init(void);
+int cpu_init_r(void);
+int cpu_init_f(void);
 
 /* cpu/.../timer.c */
 void timer_isr(void *);

include/configs/eNET.h

@@ -28,6 +28,8 @@
 #ifndef __CONFIG_H
 #define __CONFIG_H
 
+#define CONFIG_RELOC_FIXUP_WORKS
+
 /*
  * Stuff still to be dealt with -
  */

lib_i386/board.c

@@ -38,6 +38,7 @@
 #include <net.h>
 #include <ide.h>
 #include <asm/u-boot-i386.h>
+#include <elf.h>
 
 #ifdef CONFIG_BITBANGMII
 #include <miiphy.h>
@@ -45,41 +46,16 @@
 
 DECLARE_GLOBAL_DATA_PTR;
 
-extern long _i386boot_start;
-extern long _i386boot_end;
-extern long _i386boot_romdata_start;
-extern long _i386boot_romdata_dest;
-extern long _i386boot_romdata_size;
-extern long _i386boot_bss_start;
-extern long _i386boot_bss_size;
-
-/* The symbols defined by the linker script becomes pointers
- * which is somewhat inconveient ... */
-ulong i386boot_start         = (ulong)&_i386boot_start;         /* code start (in flash) defined in start.S */
-ulong i386boot_end           = (ulong)&_i386boot_end;	        /* code end (in flash) */
-ulong i386boot_romdata_start = (ulong)&_i386boot_romdata_start; /* datasegment in flash (also code+rodata end) */
-ulong i386boot_romdata_dest  = (ulong)&_i386boot_romdata_dest;  /* data location segment in ram */
-ulong i386boot_romdata_size  = (ulong)&_i386boot_romdata_size;  /* size of data segment */
-ulong i386boot_bss_start     = (ulong)&_i386boot_bss_start;     /* bss start */
-ulong i386boot_bss_size      = (ulong)&_i386boot_bss_size;      /* bss size */
-
+/* Exports from the Linker Script */
+extern ulong _i386boot_text_start;
+extern ulong _i386boot_rel_dyn_start;
+extern ulong _i386boot_rel_dyn_end;
+extern ulong _i386boot_bss_start;
+extern ulong _i386boot_bss_size;
+void ram_bootstrap (void *);
 const char version_string[] =
 	U_BOOT_VERSION" (" U_BOOT_DATE " - " U_BOOT_TIME ")";
 
-static int heap_init(void)
-{
-	/* start malloc area right after the stack */
-	ulong start = i386boot_bss_start + i386boot_bss_size +
-			CONFIG_SYS_STACK_SIZE;
-
-	/* 4-byte aligned */
-	start = (start+3)&~3;
-
-	mem_malloc_init(start, CONFIG_SYS_MALLOC_LEN);
-
-	return 0;
-}
-
 /************************************************************************
  * Init Utilities							*
  ************************************************************************
@@ -103,6 +79,7 @@ static int display_banner (void)
 {
 
 	printf ("\n\n%s\n\n", version_string);
+/*
 	printf ("U-Boot code: %08lX -> %08lX  data: %08lX -> %08lX\n"
 		"        BSS: %08lX -> %08lX stack: %08lX -> %08lX\n",
 		i386boot_start, i386boot_romdata_start-1,
@@ -111,6 +88,7 @@ static int display_banner (void)
 		i386boot_bss_start+i386boot_bss_size,
 		i386boot_bss_start+i386boot_bss_size+CONFIG_SYS_STACK_SIZE-1);
 
+*/
 
 	return (0);
 }
@@ -142,7 +120,6 @@ static void display_flash_config (ulong size)
 	print_size (size, "\n");
 }
 
-
 /*
  * Breath some life into the board...
  *
@@ -154,6 +131,7 @@ static void display_flash_config (ulong size)
  * can relocate the monitor code to RAM.
  */
 
+
 /*
  * All attempts to come up with a "common" initialization sequence
  * that works for all boards and architectures failed: some of the
@@ -169,13 +147,12 @@ static void display_flash_config (ulong size)
 typedef int (init_fnc_t) (void);
 
 init_fnc_t *init_sequence[] = {
-	cpu_init,		/* basic cpu dependent setup */
-	board_init,		/* basic board dependent setup */
+	serial_init,
+	cpu_init_r,		/* basic cpu dependent setup */
+	board_early_init_r,	/* basic board dependent setup */
 	dram_init,		/* configure available RAM banks */
-	heap_init,		/* dependant on dram_init */
 	interrupt_init,		/* set up exceptions */
 	timer_init,
-	serial_init,
 	env_init,		/* initialize environment */
 	init_baudrate,		/* initialze baudrate settings */
 	serial_init,		/* serial communications setup */
@@ -187,21 +164,86 @@ init_fnc_t *init_sequence[] = {
 
 gd_t *gd;
 
-void start_i386boot (void)
+/*
+ * Load U-Boot into RAM, initialize BSS, perform relocation adjustments
+ */
+void board_init_f (ulong stack_limit)
+{
+	void *text_start = &_i386boot_text_start;
+	void *u_boot_cmd_end = &__u_boot_cmd_end;
+	Elf32_Rel *rel_dyn_start = (Elf32_Rel *)&_i386boot_rel_dyn_start;
+	Elf32_Rel *rel_dyn_end = (Elf32_Rel *)&_i386boot_rel_dyn_end;
+	void *bss_start = &_i386boot_bss_start;
+	void *bss_size = &_i386boot_bss_size;
+
+	size_t uboot_size;
+	void *ram_start;
+	ulong rel_offset;
+	Elf32_Rel *re;
+
+	void (*start_func)(void *);
+
+	/* compiler optimization barrier needed for GCC >= 3.4 */
+	__asm__ __volatile__("": : :"memory");
+
+	uboot_size = (size_t)u_boot_cmd_end - (size_t)text_start;
+	ram_start  = (void *)stack_limit - (uboot_size + (ulong)bss_size);
+	rel_offset = text_start - ram_start;
+	start_func = ram_bootstrap - rel_offset;
+
+	/* First stage CPU initialization */
+	if (cpu_init_f() != 0)
+		hang();
+
+	/* First stage Board initialization */
+	if (board_early_init_f() != 0)
+		hang();
+
+	/* Copy U-Boot into RAM */
+	memcpy(ram_start, text_start, (size_t)uboot_size);
+
+	/* Clear BSS */
+	memset(bss_start - rel_offset,	0, (size_t)bss_size);
+
+	/* Perform relocation adjustments */
+	for (re = rel_dyn_start; re < rel_dyn_end; re++)
+	{
+		if (re->r_offset >= TEXT_BASE)
+			if (*(ulong *)re->r_offset >= TEXT_BASE)
+				*(ulong *)(re->r_offset - rel_offset) -= (Elf32_Addr)rel_offset;
+	}
+
+	start_func(ram_start);
+
+	/* NOTREACHED - relocate_code() does not return */
+	while(1);
+}
+
+/*
+ * All attempts to jump straight from board_init_f() to board_init_r()
+ * have failed, hence this special 'bootstrap' function.
+ */
+void ram_bootstrap (void *ram_start)
+{
+	static gd_t gd_data;
+
+	/* compiler optimization barrier needed for GCC >= 3.4 */
+	__asm__ __volatile__("": : :"memory");
+
+	board_init_r(&gd_data, (ulong)ram_start);
+}
+
+void board_init_r(gd_t *id, ulong ram_start)
 {
 	char *s;
 	int i;
 	ulong size;
-	static gd_t gd_data;
 	static bd_t bd_data;
 	init_fnc_t **init_fnc_ptr;
 
-#ifndef CONFIG_SKIP_RELOCATE_UBOOT
-	cmd_tbl_t *p;
-#endif
 	show_boot_progress(0x21);
 
-	gd = &gd_data;
+	gd = id;
 	/* compiler optimization barrier needed for GCC >= 3.4 */
 	__asm__ __volatile__("": : :"memory");
 
@@ -212,10 +254,11 @@ void start_i386boot (void)
 
 	gd->baudrate =  CONFIG_BAUDRATE;
 
-#ifndef CONFIG_SKIP_RELOCATE_UBOOT
-	/* Need to set relocation offset here for interrupt initialization */
-	gd->reloc_off =  CONFIG_SYS_BL_START_RAM - TEXT_BASE;
-#endif
+	gd->flags |= GD_FLG_RELOC;	/* tell others: relocation done */
+
+	mem_malloc_init((((ulong)ram_start - CONFIG_SYS_MALLOC_LEN)+3)&~3,
+			CONFIG_SYS_MALLOC_LEN);
+
 	for (init_fnc_ptr = init_sequence, i=0; *init_fnc_ptr; ++init_fnc_ptr, i++) {
 		show_boot_progress(0xa130|i);
 
@@ -225,26 +268,6 @@ void start_i386boot (void)
 	}
 	show_boot_progress(0x23);
 
-#ifndef CONFIG_SKIP_RELOCATE_UBOOT
-	for (p = &__u_boot_cmd_start; p != &__u_boot_cmd_end; p++) {
-		ulong addr;
-		addr = (ulong) (p->cmd) + gd->reloc_off;
-		p->cmd = (int (*)(struct cmd_tbl_s *, int, int, char *[]))addr;
-		addr = (ulong)(p->name) + gd->reloc_off;
-		p->name = (char *)addr;
-
-		if (p->usage != NULL) {
-			addr = (ulong)(p->usage) + gd->reloc_off;
-			p->usage = (char *)addr;
-		}
-	#ifdef	CONFIG_SYS_LONGHELP
-		if (p->help != NULL) {
-			addr = (ulong)(p->help) + gd->reloc_off;
-			p->help = (char *)addr;
-		}
-	#endif
-	}
-#endif
 	/* configure available FLASH banks */
 	size = flash_init();
 	display_flash_config(size);

lib_i386/interrupts.c

@@ -70,12 +70,12 @@ void irq_install_handler(int irq, interrupt_handler_t *handler, void *arg)
 
 	if (irq_handlers[irq].handler != NULL)
 		printf("irq_install_handler: 0x%08lx replacing 0x%08lx\n",
-		       (ulong) handler + gd->reloc_off,
+		       (ulong) handler,
 		       (ulong) irq_handlers[irq].handler);
 
 	status = disable_interrupts ();
 
-	irq_handlers[irq].handler = handler + gd->reloc_off;
+	irq_handlers[irq].handler = handler;
 	irq_handlers[irq].arg = arg;
 	irq_handlers[irq].count = 0;
 

lib_i386/timer.c

@@ -51,7 +51,7 @@ int register_timer_isr (timer_fnc_t *isr_func)
 	if (new_func == NULL)
 		return 1;
 
-	new_func->isr_func = isr_func + gd->reloc_off;
+	new_func->isr_func = isr_func;
 	new_func->next = NULL;
 
 	/*