From mboxrd@z Thu Jan 1 00:00:00 1970 From: Graeme Russ Date: Tue, 20 Dec 2011 23:06:39 +1100 Subject: [U-Boot] Where I'm going with x86 board.c Message-ID: <4EF07A4F.6020401@gmail.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de With Simon's work on generic relocation support, I thought I would throw in what I am planning for arch/x86/lib/board.c Now this is not a patch, it is a work-in-progress complete version of the file (compiles, will test soon) - If feedback is positive, I'll add this to an upcoming patch set Notice the amount of wrapping around void functions - If all other arch's follow this lead, most of this wrapping can be removed by changing the function signatures. Lines 428 - 585 are effectively the generic init sequence - The rest is wrappers, init sequence arrays, or fluff that should be moved I noticed something along the way - gd is no longer special... let me explain... Some arch's use a dedicated register for the gd pointer - This allows the pointer to be written to prior to relocation. For x86, the gd pointer is simply passed around as a function parameter early - If the init_sequence_f functions accepted a gd pointer as a parameter, there would be no need for it to be global prior to relocation and therefore no need to allocate a permanent register for it - Of course do_init_loop() would no longer be generic for both pre and post relocation. This does mess with the stand-alone API, but as discussed before, stand alone applications should not be accessing gd anyway, so there should be no API to break ;) And on that note, the following comment is well and truly wrong: * 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". And finally, here 'tis: /* * (C) Copyright 2008-2011 * Graeme Russ, * * (C) Copyright 2002 * Daniel Engstr?m, Omicron Ceti AB, * * (C) Copyright 2002 * Wolfgang Denk, DENX Software Engineering, * * (C) Copyright 2002 * Sysgo Real-Time Solutions, GmbH * Marius Groeger * * See file CREDITS for list of people who contributed to this * project. * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License as * published by the Free Software Foundation; either version 2 of * the License, or (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, * MA 02111-1307 USA */ #include #include #include #include #include #include #include #include #include #include #include #ifdef CONFIG_BITBANGMII #include #endif /* * Pointer to initial global data area * * Here we initialize it. */ #undef XTRN_DECLARE_GLOBAL_DATA_PTR #define XTRN_DECLARE_GLOBAL_DATA_PTR /* empty = allocate here */ DECLARE_GLOBAL_DATA_PTR = (gd_t *) (CONFIG_SYS_INIT_GD_ADDR); /************************************************************************ * Init Utilities * ************************************************************************ * Some of this code should be moved into the core functions, * or dropped completely, * but let's get it working (again) first... */ static int init_baudrate(void) { gd->baudrate = getenv_ulong("baudrate", 10, CONFIG_BAUDRATE); return 0; } static int display_banner(void) { printf("\n\n%s\n\n", version_string); return 0; } static int display_dram_config(void) { int i; puts("DRAM Configuration:\n"); for (i = 0; i < CONFIG_NR_DRAM_BANKS; i++) { printf("Bank #%d: %08lx ", i, gd->bd->bi_dram[i].start); print_size(gd->bd->bi_dram[i].size, "\n"); } return 0; } #ifndef CONFIG_SYS_NO_FLASH static void display_flash_config(ulong size) { puts("Flash: "); print_size(size, "\n"); } #endif /* * Breath some life into the board... * * Initialize an SMC for serial comms, and carry out some hardware * tests. * * 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. */ /* * 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". */ typedef int (init_fnc_t) (void); static int calculate_relocation_address(gd_t *); static int copy_uboot_to_ram(gd_t *); static int clear_bss(gd_t *); static int do_elf_reloc_fixups(gd_t *); init_fnc_t *init_sequence_f[] = { cpu_init_f, board_early_init_f, env_init, init_baudrate, serial_init, console_init_f, dram_init_f, NULL, }; gd_t *gd; bd_t bd_data; static int init_bd_struct_r(void) { gd->bd = &bd_data; memset(gd->bd, 0, sizeof(bd_t)); return 0; } static int mem_malloc_init_r(void) { mem_malloc_init(((gd->relocaddr - CONFIG_SYS_MALLOC_LEN)+3)&~3, CONFIG_SYS_MALLOC_LEN); return 0; } static int set_default_baudrate_r(void) { gd->baudrate = CONFIG_BAUDRATE; return 0; } #ifdef CONFIG_SERIAL_MULTI static int serial_initialize_r(void) { serial_initialize(); return 0; } #endif #ifndef CONFIG_SYS_NO_FLASH static int flash_init_r(void) { ulong size; /* configure available FLASH banks */ size = flash_init(); display_flash_config(size); show_boot_progress(0x24); return 0; } #endif static int env_relocate_r(void) { /* initialize environment */ env_relocate(); show_boot_progress(0x26); return 0; } #ifdef CONFIG_CMD_NET static int init_ip_address_r(void) { /* IP Address */ bd_data.bi_ip_addr = getenv_IPaddr("ipaddr"); return 0; } #endif #ifdef CONFIG_PCI static int pci_init_r(void) { /* * Do pci configuration */ pci_init(); return 0; } #endif static int jumptable_init_r(void) { jumptable_init(); return 0; } #if defined(CONFIG_CMD_PCMCIA) && !defined(CONFIG_CMD_IDE) static int pci_init_r(void) { puts("PCMCIA:"); pcmcia_init(); return 0; } #endif #if defined(CONFIG_CMD_KGDB) static int kgdb_init_r(void) { puts("KGDB: "); kgdb_init(); return 0; } #endif static int enable_interrupts_r(void) { /* enable exceptions */ enable_interrupts(); show_boot_progress(0x28); return 0; } #ifdef CONFIG_STATUS_LED static int status_led_set_r(void) { status_led_set(STATUS_LED_BOOT, STATUS_LED_BLINKING); udelay(20); return 0; } #endif #if defined(CONFIG_CMD_NET) static int set_bootfile_r(void) { char *s; s = getenv("bootfile"); if (s != NULL) copy_filename(BootFile, s, sizeof(BootFile)); return 0; } static int eth_initialize_r(void) { puts("Net: "); eth_initialize(gd->bd); return 0; } #ifdef CONFIG_RESET_PHY_R static int reset_phy_r(void) { #ifdef DEBUG puts("Reset Ethernet PHY\n"); #endif reset_phy(); return 0; } #endif #endif static int set_load_addr_r(void) { /* Initialize from environment */ load_addr = getenv_ulong("loadaddr", 16, load_addr); return 0; } #if defined(CONFIG_CMD_IDE) static int ide_init_r(void) { puts("IDE: "); ide_init(); return 0; } #endif #if defined(CONFIG_CMD_SCSI) static int scsi_init_r(void) { puts("SCSI: "); scsi_init(); return 0; } #endif #if defined(CONFIG_CMD_DOC) static int doc_init_r(void) { puts("DOC: "); doc_init(); return 0; } #endif #ifdef CONFIG_BITBANGMII static int bb_miiphy_init_r(void) { bb_miiphy_init(); return 0; } #endif #ifdef CONFIG_POST static int post_run_r(void) { post_run(NULL, POST_RAM | post_bootmode_get(0)); return 0; } #endif init_fnc_t *init_sequence_r[] = { init_bd_struct_r, mem_malloc_init_r, set_default_baudrate_r, cpu_init_r, /* basic cpu dependent setup */ board_early_init_r, /* basic board dependent setup */ dram_init, /* configure available RAM banks */ interrupt_init, /* set up exceptions */ timer_init, display_banner, display_dram_config, #ifdef CONFIG_SERIAL_MULTI serial_initialize_r, #endif #ifndef CONFIG_SYS_NO_FLASH flash_init_r, #endif env_relocate_r, #ifdef CONFIG_CMD_NET init_ip_address_r, #endif #ifdef CONFIG_PCI pci_init_r, #endif stdio_init, jumptable_init_r, console_init_r, #ifdef CONFIG_MISC_INIT_R misc_init_r, #endif #if defined(CONFIG_CMD_PCMCIA) && !defined(CONFIG_CMD_IDE) pci_init_r, #endif #if defined(CONFIG_CMD_KGDB) kgdb_init_r, #endif enable_interrupts_r, #ifdef CONFIG_STATUS_LED status_led_set_r, #endif set_load_addr_r, #if defined(CONFIG_CMD_NET) set_bootfile_r, #endif #if defined(CONFIG_CMD_IDE) ide_init_r, #endif #if defined(CONFIG_CMD_SCSI) scsi_init_r, #endif #if defined(CONFIG_CMD_DOC) doc_init_r, #endif #ifdef CONFIG_BITBANGMII bb_miiphy_init_r, #endif #if defined(CONFIG_CMD_NET) eth_initialize_r, #ifdef CONFIG_RESET_PHY_R reset_phy_r, #endif #endif #ifdef CONFIG_LAST_STAGE_INIT last_stage_init, #endif NULL, }; static int calculate_relocation_address(gd_t *id) { ulong text_start = (ulong)&__text_start; ulong bss_end = (ulong)&__bss_end; ulong dest_addr; ulong rel_offset; /* Calculate destination RAM Address and relocation offset */ dest_addr = id->start_addr_sp; dest_addr -= CONFIG_SYS_STACK_SIZE; dest_addr -= (bss_end - text_start); /* * Round destination address down to 16-byte boundary to keep * IDT and GDT 16-byte aligned */ dest_addr &= ~15; rel_offset = dest_addr - text_start; id->relocaddr = dest_addr; id->reloc_off = rel_offset; return 0; } static int copy_uboot_to_ram(gd_t *id) { size_t len = (size_t)&__data_end - (size_t)&__text_start; memcpy((void *)id->relocaddr, (void *)&__text_start, len); return 0; } static int clear_bss(gd_t *id) { ulong dst_addr = (ulong)&__bss_start + id->reloc_off; size_t len = (size_t)&__bss_end - (size_t)&__bss_start; memset((void *)dst_addr, 0x00, len); return 0; } static int do_elf_reloc_fixups(gd_t *id) { Elf32_Rel *re_src = (Elf32_Rel *)(&__rel_dyn_start); Elf32_Rel *re_end = (Elf32_Rel *)(&__rel_dyn_end); Elf32_Addr *offset_ptr_rom; Elf32_Addr *offset_ptr_ram; /* The size of the region of u-boot that runs out of RAM. */ uintptr_t size = (uintptr_t)&__bss_end - (uintptr_t)&__text_start; do { /* Get the location from the relocation entry */ offset_ptr_rom = (Elf32_Addr *)re_src->r_offset; /* Check that the location of the relocation is in .text */ if (offset_ptr_rom >= (Elf32_Addr *)CONFIG_SYS_TEXT_BASE) { /* Switch to the in-RAM version */ offset_ptr_ram = (Elf32_Addr *)((ulong)offset_ptr_rom + id->reloc_off); /* Check that the target points into .text */ if (*offset_ptr_ram >= CONFIG_SYS_TEXT_BASE && *offset_ptr_ram < (CONFIG_SYS_TEXT_BASE + size)) { *offset_ptr_ram += id->reloc_off; } } } while (re_src++ < re_end); return 0; } static void do_init_loop(init_fnc_t **init_fnc_ptr) { for (; *init_fnc_ptr; ++init_fnc_ptr) { WATCHDOG_RESET(); if ((*init_fnc_ptr)() != 0) hang(); } } /* Load U-Boot into RAM, initialize BSS, perform relocation adjustments */ void board_init_f(ulong boot_flags) { gd->flags = boot_flags; do_init_loop(init_sequence_f); /* SDRAM is now initialised setup a new stack in SDRAM */ setup_sdram_environment(gd->ram_size, GENERATED_GBL_DATA_SIZE); /* NOTREACHED - relocate_code() does not return */ while (1) ; } typedef void (board_init_r_t) (gd_t *, ulong); void relocate_code(ulong stack_ptr, gd_t *id, ulong reloc_addr) { board_init_r_t *board_init_r_func; /* We are running from flash, but the stack is now in SDRAM */ /* gd is still in CAR - Copy it into SDRAM */ memcpy(id, gd, sizeof(gd_t)); id->start_addr_sp = stack_ptr; if (init_cache() != 0) hang(); calculate_relocation_address(id); copy_uboot_to_ram(id); clear_bss(id); do_elf_reloc_fixups(id); board_init_r_func = board_init_r; board_init_r_func += id->reloc_off; board_init_r_func(id, id->relocaddr); /* NOTREACHED - relocate_code() does not return */ while (1) ; } void board_init_r(gd_t *id, ulong dest_addr) { /* Global data pointer is now writable */ gd = id; 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. */ for (;;) main_loop(); /* NOTREACHED - no way out of command loop except booting */ } void hang(void) { puts("### ERROR ### Please RESET the board ###\n"); for (;;) ; } unsigned long do_go_exec(ulong (*entry)(int, char * const []), int argc, char * const argv[]) { unsigned long ret = 0; char **argv_tmp; /* * x86 does not use a dedicated register to pass the pointer to * the global_data, so it is instead passed as argv[-1]. By using * argv[-1], the called 'Application' can use the contents of * argv natively. However, to safely use argv[-1] a new copy of * argv is needed with the extra element */ argv_tmp = malloc(sizeof(char *) * (argc + 1)); if (argv_tmp) { argv_tmp[0] = (char *)gd; memcpy(&argv_tmp[1], argv, (size_t)(sizeof(char *) * argc)); ret = (entry) (argc, &argv_tmp[1]); free(argv_tmp); } return ret; } void setup_pcat_compatibility(void) __attribute__((weak, alias("__setup_pcat_compatibility"))); void __setup_pcat_compatibility(void) { }