diff options
| -rw-r--r-- | Makefile | 7 | ||||
| -rw-r--r-- | bootstub.c | 37 | ||||
| -rw-r--r-- | bootstub.h | 11 | ||||
| -rw-r--r-- | e820_bios.S | 202 | ||||
| -rw-r--r-- | head.S | 51 |
5 files changed, 264 insertions, 44 deletions
@@ -1,4 +1,4 @@ -OBJ=bootstub.o spi-uart.o head.o sfi.o +OBJ=bootstub.o spi-uart.o head.o sfi.o e820_bios.o CMDLINE_SIZE ?= 0x400 CFLAGS=-m32 -ffreestanding -Wall -DCMDLINE_SIZE=${CMDLINE_SIZE} CC ?= gcc @@ -24,7 +24,10 @@ sfi.o:sfi.c ${CC} $(CFLAGS) -c sfi.c head.o:head.S bootstub.h - ${CC} $(CFLAGS) -c head.S + ${CC} $(CFLAGS) -D__ASSEMBLY__ -c head.S + +e820_bios.o:e820_bios.S bootstub.h + ${CC} $(CFLAGS) -D__ASSEMBLY__ -c e820_bios.S clean: rm -rf *.o *.bin *.elf *.bz2 *.rpm @@ -27,33 +27,6 @@ #define bs_printk(x) { if (! *(int *)SPI_UART_SUPPRESSION) bs_spi_printk(x);} -struct gdt_ptr { - u16 len; - u32 ptr; -} __attribute__((packed)); - -static void setup_gdt(void) -{ - static const u64 boot_gdt[] __attribute__((aligned(16))) = { - /* CS: code, read/execute, 4 GB, base 0 */ - [GDT_ENTRY_BOOT_CS] = GDT_ENTRY(0xc09b, 0, 0xfffff), - /* DS: data, read/write, 4 GB, base 0 */ - [GDT_ENTRY_BOOT_DS] = GDT_ENTRY(0xc093, 0, 0xfffff), - }; - static struct gdt_ptr gdt; - - gdt.len = sizeof(boot_gdt)-1; - gdt.ptr = (u32)&boot_gdt; - - asm volatile("lgdtl %0" : : "m" (gdt)); -} - -static void setup_idt(void) -{ - static const struct gdt_ptr null_idt = {0, 0}; - asm volatile("lidtl %0" : : "m" (null_idt)); -} - static void *memcpy(void *dest, const void *src, size_t count) { char *tmp = dest; @@ -101,6 +74,7 @@ static size_t strnlen(const char *s, size_t maxlen) static void setup_boot_params(struct boot_params *bp, struct setup_header *sh) { u8 *initramfs; + int nr_entries; memset(bp, 0, sizeof (struct boot_params)); bp->screen_info.orig_video_mode = 0; @@ -121,7 +95,12 @@ static void setup_boot_params(struct boot_params *bp, struct setup_header *sh) } else { bs_printk("Won't relocate initramfs, are you in SLE?\n"); } - sfi_setup_e820(bp); + if (mrst_identify_cpu() == MRST_CPU_CHIP_VALLEYVIEW2) { + nr_entries = get_e820_by_bios(bp->e820_map); + bp->e820_entries = (nr_entries > 0) ? nr_entries : 0; + } else { + sfi_setup_e820(bp); + } } static int get_32bit_entry(unsigned char *ptr) @@ -187,8 +166,6 @@ static void setup_spi(void) int bootstub(void) { - setup_idt(); - setup_gdt(); setup_spi(); bs_printk("Bootstub Version: 1.2 ...\n"); setup_boot_params((struct boot_params *)BOOT_PARAMS_OFFSET, @@ -33,11 +33,22 @@ #define GDT_ENTRY_BOOT_DS (GDT_ENTRY_BOOT_CS + 1) #define __BOOT_DS (GDT_ENTRY_BOOT_DS * 8) +#ifdef __ASSEMBLY__ +#define GDT_ENTRY(flags, base, limit) \ + ((((base) & 0xff000000) << (56-24)) | \ + (((flags) & 0x0000f0ff) << 40) | \ + (((limit) & 0x000f0000) << (48-16)) | \ + (((base) & 0x00ffffff) << 16) | \ + (((limit) & 0x0000ffff))) +#else #define GDT_ENTRY(flags, base, limit) \ (((u64)(base & 0xff000000) << 32) | \ ((u64)flags << 40) | \ ((u64)(limit & 0x00ff0000) << 32) | \ ((u64)(base & 0x00ffffff) << 16) | \ ((u64)(limit & 0x0000ffff))) +int get_e820_by_bios(void *e820_buf); +int mrst_identify_cpu(void); +#endif #endif diff --git a/e820_bios.S b/e820_bios.S new file mode 100644 index 0000000..833cd31 --- /dev/null +++ b/e820_bios.S @@ -0,0 +1,202 @@ +/* + * e820_bios.S: read e820 by int 15h call. + * + * The C language function exported by this file is: + * int get_e820_by_bios(void *e820_buf); + * @e820_buf: e820 mem map buffer, allocated by caller + * return: number of e820 entries + * + * Copyright (C) 2013 Intel Corporation. + * Author: Bin Gao <bin.gao@intel.com> + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + * + * This program is distributed in the hope 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., + * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA. + * + */ + +#include "bootstub.h" + +/* Real mode low memory layout */ +#define IDT_START 0x0 +#define RELOCATED_START 0xa000 +#define STACK_START 0xb000 +#define DATA_START 0xb200 + +#define SAVED_GDTR_ADDR 0xb100 +#define SAVED_IDTR_ADDR 0xb110 +#define COUNT_ADDR 0xb120 +#define TOTAL_COUNT_ADDR 0xb130 +#define MIN_BUF_LEN 20 +#define BUF_LEN 2048 +#define MAX_NR_ENTRIES 128 + +#define SMAP 0x534d4150 +#define E820 0xe820 + +.text +.section ".text.head","ax",@progbits + + .code32 + .globl get_e820_by_bios +get_e820_by_bios: + jmp start_32bit + + .balign 16 +idtr: + .word 0xffff + .long IDT_START + + .balign 16 +gdt: + .quad 0 + .quad GDT_ENTRY(0x009b, 0, 0xffff) + .quad GDT_ENTRY(0x0093, 0, 0xffff) +gdtr: + .word 3*8-1 + .long gdt + +saved_esp: + .long 0 + +start_32bit: + pushal + pushfl + + /* Save ESP, GDTR and IDTR registers */ + movl $saved_esp, %eax + movl %esp, (%eax) + xorl %eax, %eax + sidtl SAVED_IDTR_ADDR(%eax) + sgdtl SAVED_GDTR_ADDR(%eax) + + /* Relocate real mode codes to 64k segment */ + movl $relocated_end + 4, %ecx + subl $relocated_start, %ecx + shrl $2, %ecx + movl $relocated_start, %esi + movl $RELOCATED_START, %edi + rep movsl + + /* Set up real mode IDT */ + lidtl %cs:idtr + + /* Set up real mode GDT */ + lgdtl %cs:gdtr + movl $16, %ecx + movl %ecx, %ds + movl %ecx, %es + movl %ecx, %fs + movl %ecx, %gs + movl %ecx, %ss + + /* Switch to 16bit segment */ + ljmpl $8, $RELOCATED_START + + .code16 +relocated_start: +reloc_base = . + + /* Switch to real mode */ + andb $0x10, %al + movl %eax, %cr0 + ljmpw $0, $realmode_entry - relocated_start + RELOCATED_START + +realmode_entry = . + /* In real mode now, set up segment selectors */ + movl $0, %eax + movl %eax, %ds + movl %eax, %es + movl %eax, %ss + movl %eax, %gs + movl %eax, %fs + + movl $STACK_START, %esp + + /* Do int 15h call */ + movl $COUNT_ADDR, %eax + movl $0, (%eax) + movl $TOTAL_COUNT_ADDR, %eax + movl $0, (%eax) + xorl %ebx, %ebx + movw $DATA_START, %di +again: + movw $E820, %ax + movw $BUF_LEN, %cx + movl $SMAP, %edx + int $0x15 + jc error /* EFLGAS.CF is set */ + cmpl $SMAP, %eax + jne error /* eax is not 'SMAP' */ + cmpw $MIN_BUF_LEN, %cx + jl error /* returned buffer len < 20 */ + cmpw $BUF_LEN, %cx + jg error /* returned buffer len > provided buffer len */ + movl $TOTAL_COUNT_ADDR, %eax + addw %cx, (%eax) + movl $COUNT_ADDR, %eax + incl (%eax) + movl (%eax), %eax + cmpl $MAX_NR_ENTRIES, %eax /* max supported entries: 128 */ + jge done + testl %ebx, %ebx /* ebx == 0: done, ebx != 0: continue */ + je done + addw %cx, %di + jmp again +done: + jmp 2f +error: + movl $COUNT_ADDR, %eax + movl $~0, (%eax) +2: + + /* Switch back to protected mode */ + xorl %ebx, %ebx + lidtl SAVED_IDTR_ADDR(%ebx) + lgdtl SAVED_GDTR_ADDR(%ebx) + movl %cr0, %ebx + orb $1, %bl + movl %ebx, %cr0 + .byte 0x66, 0xea /* opcode(JMP FAR) with operand size override */ + .long resumed_protected_mode /* offset */ + .word __BOOT_CS /* segment selector */ +relocated_end = . + + .code32 +resumed_protected_mode: + cli /* in case real mode codes turn on interrrupt! */ + /* Restore segment registers */ + movl $__BOOT_DS, %ebx + movl %ebx, %ds + movl %ebx, %es + movl %ebx, %gs + movl %ebx, %fs + movl %ebx, %ss + + /* Restore stack pointer */ + movl $saved_esp, %eax + movl (%eax), %esp + + /* Copy e820 data from our buffer to caller's buffer */ + xorl %eax, %eax + movl TOTAL_COUNT_ADDR(%eax), %ecx + movl $DATA_START, %esi + movl 40(%esp), %edi + rep movsb + + popfl + popal + + /* Return number of e820 entries */ + movl $COUNT_ADDR, %eax + movl (%eax), %eax + ret @@ -62,26 +62,53 @@ _start: cld cli - /* setup stack, because we are heading off to "C" */ - movl $STACK_OFFSET, %esp - /* after call bootstub, GDT was set (0x10 and 0x18) IDT was clear - * eax will store 32bit entry of bzImage - */ - calll bootstub - /* DS=ES=FS=GS=10 */ + + /* Set our own GDT and IDT, don't derive from IAFW */ + lgdtl %cs:gdtr + lidtl %cs:idtr + + /* Load segment registers per protected mode kernel entry requirement: + * CS=0x10, + * DS=ES=SS=FS=GS=0x18 + */ + ljmp $__BOOT_CS, $1f +1: movl $__BOOT_DS, %ebx movl %ebx, %ds movl %ebx, %es movl %ebx, %fs movl %ebx, %gs movl %ebx, %ss - ljmp $__BOOT_CS,$1f -1: + + /* setup stack, because we are heading off to "C" */ + movl $STACK_OFFSET, %esp + + /* bootstub() returns 32bit entry address of bzImage, stored in eax */ + calll bootstub + /* tell kernel where is boot_param */ movl $(BOOT_PARAMS_OFFSET), %esi xor %ebp, %ebp xor %edi, %edi xor %ebx, %ebx - - jmpl *%eax # Jump to the 32-bit entrypoint - + + /* Jump to the 32-bit entrypoint */ + jmpl *%eax + + .balign 8 +gdt: + .quad 0 + .quad 0 + .quad GDT_ENTRY(0xc09b, 0, 0xfffff) + .quad GDT_ENTRY(0xc093, 0, 0xfffff) +gdtr: + .word 4*8-1 + .long gdt + + .balign 8 +idt: + .quad 0 + .quad 0 +idtr: + .word 2*8-1 + .long idt |