diff options
Diffstat (limited to 'arch/x86/lib')
| -rw-r--r-- | arch/x86/lib/board.c | 186 | ||||
| -rw-r--r-- | arch/x86/lib/init_helpers.c | 75 | ||||
| -rw-r--r-- | arch/x86/lib/relocate.c | 32 | 
3 files changed, 168 insertions, 125 deletions
diff --git a/arch/x86/lib/board.c b/arch/x86/lib/board.c index 89721c7c0..5f0b62cea 100644 --- a/arch/x86/lib/board.c +++ b/arch/x86/lib/board.c @@ -35,7 +35,7 @@  #include <watchdog.h>  #include <stdio_dev.h>  #include <asm/u-boot-x86.h> -#include <asm/processor.h> +#include <asm/relocate.h>  #include <asm/init_helpers.h>  #include <asm/init_wrappers.h> @@ -43,31 +43,58 @@  /*   * Breath some life into the board...   * - * Initialize an SMC for serial comms, and carry out some hardware - * tests. + * Getting the board up and running is a three-stage process: + *  1) Execute from Flash, SDRAM Uninitialised + *     At this point, there is a limited amount of non-SDRAM memory + *     (typically the CPU cache, but can also be SRAM or even a buffer of + *     of some peripheral). This limited memory is used to hold: + *      - The initial copy of the Global Data Structure + *      - A temporary stack + *      - A temporary x86 Global Descriptor Table + *      - The pre-console buffer (if enabled)   * - * The first part of initialization is running from Flash memory; - * its main purpose is to initialize the RAM so that we - * can relocate the monitor code to RAM. + *     The following is performed during this phase of execution: + *      - Core low-level CPU initialisation + *      - Console initialisation + *      - SDRAM initialisation + * + *  2) Execute from Flash, SDRAM Initialised + *     At this point we copy Global Data from the initial non-SDRAM + *     memory and set up the permanent stack in SDRAM. The CPU cache is no + *     longer being used as temporary memory, so we can now fully enable + *     it. + * + *     The following is performed during this phase of execution: + *      - Create final stack in SDRAM + *      - Copy Global Data from temporary memory to SDRAM + *      - Enabling of CPU cache(s), + *      - Copying of U-Boot code and data from Flash to RAM + *      - Clearing of the BSS + *      - ELF relocation adjustments + * + *  3) Execute from SDRAM + *     The following is performed during this phase of execution: + *      - All remaining initialisation   */  /* - * All attempts to come up with a "common" initialization sequence - * that works for all boards and architectures failed: some of the - * requirements are just _too_ different. To get rid of the resulting - * mess of board dependend #ifdef'ed code we now make the whole - * initialization sequence configurable to the user. - * - * The requirements for any new initalization function is simple: it - * receives a pointer to the "global data" structure as it's only - * argument, and returns an integer return code, where 0 means - * "continue" and != 0 means "fatal error, hang the system". + * The requirements for any new initalization function is simple: it is + * a function with no parameters which returns an integer return code, + * where 0 means "continue" and != 0 means "fatal error, hang the system"   */  typedef int (init_fnc_t) (void); -static int calculate_relocation_address(void); -static int copy_gd_to_ram(void); - +/* + * init_sequence_f is the list of init functions which are run when U-Boot + * is executing from Flash with a limited 'C' environment. The following + * limitations must be considered when implementing an '_f' function: + *  - 'static' variables are read-only + *  - Global Data (gd->xxx) is read/write + *  - Stack space is limited + * + * The '_f' sequence must, as a minimum, initialise SDRAM. It _should_ + * also initialise the console (to provide early debug output) + */  init_fnc_t *init_sequence_f[] = {  	cpu_init_f,  	board_early_init_f, @@ -81,7 +108,39 @@ init_fnc_t *init_sequence_f[] = {  	NULL,  }; +/* + * init_sequence_f_r is the list of init functions which are run when + * U-Boot is executing from Flash with a semi-limited 'C' environment. + * The following limitations must be considered when implementing an + * '_f_r' function: + *  - 'static' variables are read-only + *  - Global Data (gd->xxx) is read/write + * + * The '_f_r' sequence must, as a minimum, copy U-Boot to RAM (if + * supported).  It _should_, if possible, copy global data to RAM and + * initialise the CPU caches (to speed up the relocation process) + */ +init_fnc_t *init_sequence_f_r[] = { +	copy_gd_to_ram_f_r, +	init_cache_f_r, +	copy_uboot_to_ram, +	clear_bss, +	do_elf_reloc_fixups, + +	NULL, +}; + +/* + * init_sequence_r is the list of init functions which are run when U-Boot + * is executing from RAM with a full 'C' environment. There are no longer + * any limitations which must be considered when implementing an '_r' + * function, (i.e.'static' variables are read/write) + * + * If not already done, the '_r' sequence must copy global data to RAM and + * (should) initialise the CPU caches. + */  init_fnc_t *init_sequence_r[] = { +	set_reloc_flag_r,  	init_bd_struct_r,  	mem_malloc_init_r,  	cpu_init_r, @@ -157,43 +216,6 @@ static void do_init_loop(init_fnc_t **init_fnc_ptr)  	}  } -static int calculate_relocation_address(void) -{ -	ulong text_start = (ulong)&__text_start; -	ulong bss_end = (ulong)&__bss_end; -	ulong dest_addr; - -	/* -	 * NOTE: All destination address are rounded down to 16-byte -	 *       boundary to satisfy various worst-case alignment -	 *       requirements -	 */ - -	/* Global Data is at top of available memory */ -	dest_addr = gd->ram_size; -	dest_addr -= GENERATED_GBL_DATA_SIZE; -	dest_addr &= ~15; -	gd->new_gd_addr = dest_addr; - -	/* GDT is below Global Data */ -	dest_addr -= X86_GDT_SIZE; -	dest_addr &= ~15; -	gd->gdt_addr = dest_addr; - -	/* Stack is below GDT */ -	gd->start_addr_sp = dest_addr; - -	/* U-Boot is below the stack */ -	dest_addr -= CONFIG_SYS_STACK_SIZE; -	dest_addr -= (bss_end - text_start); -	dest_addr &= ~15; -	gd->relocaddr = dest_addr; -	gd->reloc_off = (dest_addr - text_start); - -	return 0; -} - -/* Perform all steps necessary to get RAM initialised ready for relocation */  void board_init_f(ulong boot_flags)  {  	gd->flags = boot_flags; @@ -201,10 +223,9 @@ void board_init_f(ulong boot_flags)  	do_init_loop(init_sequence_f);  	/* -	 * SDRAM is now initialised, U-Boot has been copied into SDRAM, -	 * the BSS has been cleared etc. The final stack can now be setup -	 * in SDRAM. Code execution will continue (momentarily) in Flash, -	 * but with the stack in SDRAM and Global Data in temporary memory +	 * SDRAM and console are now initialised. The final stack can now +	 * be setup in SDRAM. Code execution will continue in Flash, but +	 * with the stack in SDRAM and Global Data in temporary memory  	 * (CPU cache)  	 */  	board_init_f_r_trampoline(gd->start_addr_sp); @@ -216,51 +237,22 @@ void board_init_f(ulong boot_flags)  void board_init_f_r(void)  { -	if (copy_gd_to_ram() != 0) -		hang(); - -	if (init_cache() != 0) -		hang(); - -	relocate_code(0, gd, 0); - -	/* NOTREACHED - relocate_code() does not return */ -	while (1) -		; -} - -static int copy_gd_to_ram(void) -{ -	gd_t *ram_gd; +	do_init_loop(init_sequence_f_r);  	/* -	 * Global data is still in temporary memory (the CPU cache). -	 * calculate_relocation_address() has set gd->new_gd_addr to -	 * where the global data lives in RAM but getting it there -	 * safely is a bit tricky due to the 'F-Segment Hack' that -	 * we need to use for x86 +	 * U-Boot has been copied into SDRAM, the BSS has been cleared etc. +	 * Transfer execution from Flash to RAM by calculating the address +	 * of the in-RAM copy of board_init_r() and calling it  	 */ -	ram_gd = (gd_t *)gd->new_gd_addr; -	memcpy((void *)ram_gd, gd, sizeof(gd_t)); +	(board_init_r + gd->reloc_off)(gd, gd->relocaddr); -	/* -	 * Reload the Global Descriptor Table so FS points to the -	 * in-RAM copy of Global Data (calculate_relocation_address() -	 * has already calculated the in-RAM location of the GDT) -	 */ -	ram_gd->gd_addr = (ulong)ram_gd; -	init_gd(ram_gd, (u64 *)gd->gdt_addr); - -	return 0; +	/* NOTREACHED - board_init_r() does not return */ +	while (1) +		;  }  void board_init_r(gd_t *id, ulong dest_addr)  { -	gd->flags |= GD_FLG_RELOC; - -	/* compiler optimization barrier needed for GCC >= 3.4 */ -	__asm__ __volatile__("" : : : "memory"); -  	do_init_loop(init_sequence_r);  	/* main_loop() can return to retry autoboot, if so just run it again. */ diff --git a/arch/x86/lib/init_helpers.c b/arch/x86/lib/init_helpers.c index 547b18059..9f4dee034 100644 --- a/arch/x86/lib/init_helpers.c +++ b/arch/x86/lib/init_helpers.c @@ -29,6 +29,7 @@  #include <ide.h>  #include <serial.h>  #include <status_led.h> +#include <asm/processor.h>  #include <asm/u-boot-x86.h>  #include <asm/init_helpers.h> @@ -70,6 +71,80 @@ int init_baudrate_f(void)  	return 0;  } +int calculate_relocation_address(void) +{ +	ulong text_start = (ulong)&__text_start; +	ulong bss_end = (ulong)&__bss_end; +	ulong dest_addr; + +	/* +	 * NOTE: All destination address are rounded down to 16-byte +	 *       boundary to satisfy various worst-case alignment +	 *       requirements +	 */ + +	/* Global Data is at top of available memory */ +	dest_addr = gd->ram_size; +	dest_addr -= GENERATED_GBL_DATA_SIZE; +	dest_addr &= ~15; +	gd->new_gd_addr = dest_addr; + +	/* GDT is below Global Data */ +	dest_addr -= X86_GDT_SIZE; +	dest_addr &= ~15; +	gd->gdt_addr = dest_addr; + +	/* Stack is below GDT */ +	gd->start_addr_sp = dest_addr; + +	/* U-Boot is below the stack */ +	dest_addr -= CONFIG_SYS_STACK_SIZE; +	dest_addr -= (bss_end - text_start); +	dest_addr &= ~15; +	gd->relocaddr = dest_addr; +	gd->reloc_off = (dest_addr - text_start); + +	return 0; +} + +int copy_gd_to_ram_f_r(void) +{ +	gd_t *ram_gd; + +	/* +	 * Global data is still in temporary memory (the CPU cache). +	 * calculate_relocation_address() has set gd->new_gd_addr to +	 * where the global data lives in RAM but getting it there +	 * safely is a bit tricky due to the 'F-Segment Hack' that +	 * we need to use for x86 +	 */ +	ram_gd = (gd_t *)gd->new_gd_addr; +	memcpy((void *)ram_gd, gd, sizeof(gd_t)); + +	/* +	 * Reload the Global Descriptor Table so FS points to the +	 * in-RAM copy of Global Data (calculate_relocation_address() +	 * has already calculated the in-RAM location of the GDT) +	 */ +	ram_gd->gd_addr = (ulong)ram_gd; +	init_gd(ram_gd, (u64 *)gd->gdt_addr); + +	return 0; +} + +int init_cache_f_r(void) +{ +	/* Initialise the CPU cache(s) */ +	return init_cache(); +} + +int set_reloc_flag_r(void) +{ +	gd->flags = GD_FLG_RELOC; + +	return 0; +} +  int mem_malloc_init_r(void)  {  	mem_malloc_init(((gd->relocaddr - CONFIG_SYS_MALLOC_LEN)+3)&~3, diff --git a/arch/x86/lib/relocate.c b/arch/x86/lib/relocate.c index badb5f84f..200baaba6 100644 --- a/arch/x86/lib/relocate.c +++ b/arch/x86/lib/relocate.c @@ -34,13 +34,10 @@  #include <common.h>  #include <malloc.h>  #include <asm/u-boot-x86.h> +#include <asm/relocate.h>  #include <elf.h> -static int copy_uboot_to_ram(void); -static int clear_bss(void); -static int do_elf_reloc_fixups(void); - -static int copy_uboot_to_ram(void) +int copy_uboot_to_ram(void)  {  	size_t len = (size_t)&__data_end - (size_t)&__text_start; @@ -49,7 +46,7 @@ static int copy_uboot_to_ram(void)  	return 0;  } -static int clear_bss(void) +int clear_bss(void)  {  	ulong dst_addr = (ulong)&__bss_start + gd->reloc_off;  	size_t len = (size_t)&__bss_end - (size_t)&__bss_start; @@ -59,7 +56,7 @@ static int clear_bss(void)  	return 0;  } -static int do_elf_reloc_fixups(void) +int do_elf_reloc_fixups(void)  {  	Elf32_Rel *re_src = (Elf32_Rel *)(&__rel_dyn_start);  	Elf32_Rel *re_end = (Elf32_Rel *)(&__rel_dyn_end); @@ -92,24 +89,3 @@ static int do_elf_reloc_fixups(void)  	return 0;  } - -void relocate_code(ulong dummy_1, gd_t *id, ulong dummy_2) -{ -	/* -	 * Copy U-Boot into RAM, clear the BSS and perform relocation -	 * adjustments -	 */ -	copy_uboot_to_ram(); -	clear_bss(); -	do_elf_reloc_fixups(); - -	/* -	 * Transfer execution from Flash to RAM by calculating the address -	 * of the in-RAM copy of board_init_r() and calling it -	 */ -	(board_init_r + gd->reloc_off)(gd, gd->relocaddr); - -	/* NOTREACHED - board_init_r() does not return */ -	while (1) -		; -}  |