/*- * Copyright (c) 2015 Roger Pau Monne * Copyright (c) 2003 Peter Wemm * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * $FreeBSD$ */ #include #include #include #include #include #define __ASSEMBLY__ #include #include "assym.s" #define VTOP(x) ((x) - KERNBASE) #define ENTRY_SIZE 8 /* sizeof(uint64_t) */ #define MiB(x) (x * 1024 * 1024) #define GDT_32CODE 0x08 #define GDT_DATA 0x10 ELFNOTE(Xen, XEN_ELFNOTE_PHYS_ENTRY, .long, xen_start32 - KERNBASE) .text .code32 NON_GPROF_ENTRY(xen_start32) /* Load flat GDT */ movl $VTOP(gdtdesc32), %eax lgdt (%eax) jmp $GDT_32CODE,$VTOP(reload_cs) reload_cs: movw $GDT_DATA, %ax movw %ax, %ds movw %ax, %es movw %ax, %ss movl $VTOP(bootstack), %esp /* Don't trust what the loader gives for eflags. */ pushl $PSL_KERNEL popfl /* * Create the page tables. * The first 1GB is mapped using 2MB entries. */ movl $0, %eax pgbuild: cmp $(PAGE_SIZE/ENTRY_SIZE), %eax jae pgbuild_done /* PT4[i] = VTOP(&PT3[0]) | PG_V | PG_RW | PG_U */ movl $VTOP(PT4), %ecx movl $VTOP(PT3), %edx orl $(PG_V | PG_RW | PG_U), %edx movl %edx, (%ecx,%eax,ENTRY_SIZE) /* PT3[i] = VTOP(&PT2[0]) | PG_V | PG_RW | PG_U */ movl $VTOP(PT3), %ecx movl $VTOP(PT2), %edx orl $(PG_V | PG_RW | PG_U), %edx movl %edx, (%ecx,%eax,ENTRY_SIZE) /* PT2[i] = i * 2MiB | PG_V | PG_RW | PG_PS | PG_U */ movl $VTOP(PT2), %ecx imull $MiB(2), %eax, %edx orl $(PG_V | PG_RW | PG_PS | PG_U), %edx movl %edx, (%ecx,%eax,ENTRY_SIZE) inc %eax jmp pgbuild pgbuild_done: /* Turn on EFER.LME */ movl $MSR_EFER, %ecx rdmsr orl $EFER_LME, %eax wrmsr /* Turn on PAE */ movl %cr4, %eax orl $CR4_PAE, %eax movl %eax, %cr4 /* Set %cr3 for PT4 */ movl $VTOP(PT4), %eax movl %eax, %cr3 /* Turn on paging (implicitly sets EFER.LMA) */ movl %cr0, %eax orl $CR0_PG, %eax movl %eax, %cr0 /* Now we're in compatability mode. set %cs for long mode */ movl $VTOP(gdtdesc), %eax lgdt (%eax) ljmp $0x8, $VTOP(longmode) .code64 longmode: /* We're still running V=P, jump to entry point */ movq $bootstack, %rsp movq $hammer_time_xen, %rax pushq %rax ret /* NOTREACHED */ 0: hlt jmp 0b /* Space for initial page tables */ .data .p2align 12,0x40 PT4: .space 0x1000 PT3: .space 0x1000 PT2: .space 0x1000 /* 64bit GDT */ gdtdesc: .word gdtend - gdt .long VTOP(gdt) # low .long 0 # high gdt: .long 0 # null descriptor .long 0 .long 0x00000000 # %cs .long 0x00209800 .long 0x00000000 # %ds .long 0x00008000 gdtend: /* 32bit GDT */ gdtdesc32: .word gdt32end - gdt32 .long VTOP(gdt32) .long 0 gdt32: .long 0 # null descriptor .long 0 .long 0x0000ffff # %cs .long 0x00cf9a00 .long 0x0000ffff # %ds, %es, %ss .long 0x00cf9200 gdt32end: