/* * (C) Copyright 2002 * Daniel Engström, Omicron Ceti AB, daniel@omicron.se. * * (C) Copyright 2002 * Sysgo Real-Time Solutions, GmbH * Marius Groeger * * (C) Copyright 2002 * Sysgo Real-Time Solutions, GmbH * Alex Zuepke * * 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 */ /* * CPU specific code */ #include #include #include #include #include /* Constructor for a conventional segment GDT (or LDT) entry */ /* This is a macro so it can be used in initializers */ #define GDT_ENTRY(flags, base, limit) \ ((((base) & 0xff000000ULL) << (56-24)) | \ (((flags) & 0x0000f0ffULL) << 40) | \ (((limit) & 0x000f0000ULL) << (48-16)) | \ (((base) & 0x00ffffffULL) << 16) | \ (((limit) & 0x0000ffffULL))) /* * Set up the GDT */ struct gdt_ptr { u16 len; u32 ptr; } __attribute__((packed)); static void reload_gdt(void) { /* There are machines which are known to not boot with the GDT being 8-byte unaligned. Intel recommends 16 byte alignment. */ static const u64 boot_gdt[] __attribute__((aligned(16))) = { /* CS: code, read/execute, 4 GB, base 0 */ [GDT_ENTRY_32BIT_CS] = GDT_ENTRY(0xc09b, 0, 0xfffff), /* DS: data, read/write, 4 GB, base 0 */ [GDT_ENTRY_32BIT_DS] = GDT_ENTRY(0xc093, 0, 0xfffff), /* 16-bit CS: code, read/execute, 64 kB, base 0 */ [GDT_ENTRY_16BIT_CS] = GDT_ENTRY(0x109b, 0, 0x0ffff), /* 16-bit DS: data, read/write, 64 kB, base 0 */ [GDT_ENTRY_16BIT_DS] = GDT_ENTRY(0x1093, 0, 0x0ffff), }; static struct gdt_ptr gdt; gdt.len = sizeof(boot_gdt)-1; gdt.ptr = (u32)&boot_gdt; asm volatile("lgdtl %0\n" \ "movl $((2+1)*8), %%ecx\n" \ "movl %%ecx, %%ds\n" \ "movl %%ecx, %%es\n" \ "movl %%ecx, %%fs\n" \ "movl %%ecx, %%gs\n" \ "movl %%ecx, %%ss" \ : : "m" (gdt) : "ecx"); } int cpu_init_f(void) { const u32 em_rst = ~X86_CR0_EM; const u32 mp_ne_set = X86_CR0_MP | X86_CR0_NE; /* initialize FPU, reset EM, set MP and NE */ asm ("fninit\n" \ "movl %%cr0, %%eax\n" \ "andl %0, %%eax\n" \ "orl %1, %%eax\n" \ "movl %%eax, %%cr0\n" \ : : "i" (em_rst), "i" (mp_ne_set) : "eax"); return 0; } int cpu_init_r(void) { reload_gdt(); /* Initialize core interrupt and exception functionality of CPU */ cpu_init_interrupts (); return 0; } int do_reset(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[]) { printf ("resetting ...\n"); udelay(50000); /* wait 50 ms */ disable_interrupts(); reset_cpu(0); /*NOTREACHED*/ return 0; } void flush_cache (unsigned long dummy1, unsigned long dummy2) { asm("wbinvd\n"); return; } void __attribute__ ((regparm(0))) generate_gpf(void); /* segment 0x70 is an arbitrary segment which does not exist */ asm(".globl generate_gpf\n" ".hidden generate_gpf\n" ".type generate_gpf, @function\n" "generate_gpf:\n" "ljmp $0x70, $0x47114711\n"); void __reset_cpu(ulong addr) { printf("Resetting using i386 Triple Fault\n"); set_vector(13, generate_gpf); /* general protection fault handler */ set_vector(8, generate_gpf); /* double fault handler */ generate_gpf(); /* start the show */ } void reset_cpu(ulong addr) __attribute__((weak, alias("__reset_cpu")));