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-rw-r--r--arch/x86/cpu/cpu.c258
1 files changed, 258 insertions, 0 deletions
diff --git a/arch/x86/cpu/cpu.c b/arch/x86/cpu/cpu.c
new file mode 100644
index 0000000..7a914a5
--- /dev/null
+++ b/arch/x86/cpu/cpu.c
@@ -0,0 +1,258 @@
+/*
+ * (C) Copyright 2008-2011
+ * Graeme Russ, <graeme.russ@gmail.com>
+ *
+ * (C) Copyright 2002
+ * Daniel Engström, Omicron Ceti AB, <daniel@omicron.se>
+ *
+ * (C) Copyright 2002
+ * Sysgo Real-Time Solutions, GmbH <www.elinos.com>
+ * Marius Groeger <mgroeger@sysgo.de>
+ *
+ * (C) Copyright 2002
+ * Sysgo Real-Time Solutions, GmbH <www.elinos.com>
+ * Alex Zuepke <azu@sysgo.de>
+ *
+ * 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 <common.h>
+#include <command.h>
+#include <asm/control_regs.h>
+#include <asm/processor.h>
+#include <asm/processor-flags.h>
+#include <asm/interrupt.h>
+#include <linux/compiler.h>
+
+/*
+ * Constructor for a conventional segment GDT (or LDT) entry
+ * This is a macro so it can be used in initialisers
+ */
+#define GDT_ENTRY(flags, base, limit) \
+ ((((base) & 0xff000000ULL) << (56-24)) | \
+ (((flags) & 0x0000f0ffULL) << 40) | \
+ (((limit) & 0x000f0000ULL) << (48-16)) | \
+ (((base) & 0x00ffffffULL) << 16) | \
+ (((limit) & 0x0000ffffULL)))
+
+struct gdt_ptr {
+ u16 len;
+ u32 ptr;
+} __packed;
+
+static void load_ds(u32 segment)
+{
+ asm volatile("movl %0, %%ds" : : "r" (segment * X86_GDT_ENTRY_SIZE));
+}
+
+static void load_es(u32 segment)
+{
+ asm volatile("movl %0, %%es" : : "r" (segment * X86_GDT_ENTRY_SIZE));
+}
+
+static void load_fs(u32 segment)
+{
+ asm volatile("movl %0, %%fs" : : "r" (segment * X86_GDT_ENTRY_SIZE));
+}
+
+static void load_gs(u32 segment)
+{
+ asm volatile("movl %0, %%gs" : : "r" (segment * X86_GDT_ENTRY_SIZE));
+}
+
+static void load_ss(u32 segment)
+{
+ asm volatile("movl %0, %%ss" : : "r" (segment * X86_GDT_ENTRY_SIZE));
+}
+
+static void load_gdt(const u64 *boot_gdt, u16 num_entries)
+{
+ struct gdt_ptr gdt;
+
+ gdt.len = (num_entries * 8) - 1;
+ gdt.ptr = (u32)boot_gdt;
+
+ asm volatile("lgdtl %0\n" : : "m" (gdt));
+}
+
+void setup_gdt(gd_t *id, u64 *gdt_addr)
+{
+ /* CS: code, read/execute, 4 GB, base 0 */
+ gdt_addr[X86_GDT_ENTRY_32BIT_CS] = GDT_ENTRY(0xc09b, 0, 0xfffff);
+
+ /* DS: data, read/write, 4 GB, base 0 */
+ gdt_addr[X86_GDT_ENTRY_32BIT_DS] = GDT_ENTRY(0xc093, 0, 0xfffff);
+
+ /* FS: data, read/write, 4 GB, base (Global Data Pointer) */
+ id->arch.gd_addr = id;
+ gdt_addr[X86_GDT_ENTRY_32BIT_FS] = GDT_ENTRY(0xc093,
+ (ulong)&id->arch.gd_addr, 0xfffff);
+
+ /* 16-bit CS: code, read/execute, 64 kB, base 0 */
+ gdt_addr[X86_GDT_ENTRY_16BIT_CS] = GDT_ENTRY(0x109b, 0, 0x0ffff);
+
+ /* 16-bit DS: data, read/write, 64 kB, base 0 */
+ gdt_addr[X86_GDT_ENTRY_16BIT_DS] = GDT_ENTRY(0x1093, 0, 0x0ffff);
+
+ load_gdt(gdt_addr, X86_GDT_NUM_ENTRIES);
+ load_ds(X86_GDT_ENTRY_32BIT_DS);
+ load_es(X86_GDT_ENTRY_32BIT_DS);
+ load_gs(X86_GDT_ENTRY_32BIT_DS);
+ load_ss(X86_GDT_ENTRY_32BIT_DS);
+ load_fs(X86_GDT_ENTRY_32BIT_FS);
+}
+
+int __weak x86_cleanup_before_linux(void)
+{
+#ifdef CONFIG_BOOTSTAGE_STASH
+ bootstage_stash((void *)CONFIG_BOOTSTAGE_STASH,
+ CONFIG_BOOTSTAGE_STASH_SIZE);
+#endif
+
+ return 0;
+}
+
+int x86_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_f(void) __attribute__((weak, alias("x86_cpu_init_f")));
+
+int x86_cpu_init_r(void)
+{
+ /* Initialize core interrupt and exception functionality of CPU */
+ cpu_init_interrupts();
+ return 0;
+}
+int cpu_init_r(void) __attribute__((weak, alias("x86_cpu_init_r")));
+
+void x86_enable_caches(void)
+{
+ unsigned long cr0;
+
+ cr0 = read_cr0();
+ cr0 &= ~(X86_CR0_NW | X86_CR0_CD);
+ write_cr0(cr0);
+ wbinvd();
+}
+void enable_caches(void) __attribute__((weak, alias("x86_enable_caches")));
+
+void x86_disable_caches(void)
+{
+ unsigned long cr0;
+
+ cr0 = read_cr0();
+ cr0 |= X86_CR0_NW | X86_CR0_CD;
+ wbinvd();
+ write_cr0(cr0);
+ wbinvd();
+}
+void disable_caches(void) __attribute__((weak, alias("x86_disable_caches")));
+
+int x86_init_cache(void)
+{
+ enable_caches();
+
+ return 0;
+}
+int init_cache(void) __attribute__((weak, alias("x86_init_cache")));
+
+int do_reset(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
+{
+ printf("resetting ...\n");
+
+ /* wait 50 ms */
+ udelay(50000);
+ disable_interrupts();
+ reset_cpu(0);
+
+ /*NOTREACHED*/
+ return 0;
+}
+
+void flush_cache(unsigned long dummy1, unsigned long dummy2)
+{
+ asm("wbinvd\n");
+}
+
+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 x86 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")));
+
+int dcache_status(void)
+{
+ return !(read_cr0() & 0x40000000);
+}
+
+/* Define these functions to allow ehch-hcd to function */
+void flush_dcache_range(unsigned long start, unsigned long stop)
+{
+}
+
+void invalidate_dcache_range(unsigned long start, unsigned long stop)
+{
+}
+
+void dcache_enable(void)
+{
+ enable_caches();
+}
+
+void dcache_disable(void)
+{
+ disable_caches();
+}
+
+void icache_enable(void)
+{
+}
+
+void icache_disable(void)
+{
+}
+
+int icache_status(void)
+{
+ return 1;
+}
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