Hi Damien On Sat, Jan 21, 2023 at 3:05 AM Damien Zammit <dam...@zamaudio.com> wrote:
> --- > i386/i386/cpu_number.c | 37 ++++++++++ > i386/i386/cpuboot.S | 164 +++++++++++++++++++++++++++++++++++++++++ > 2 files changed, 201 insertions(+) > create mode 100644 i386/i386/cpu_number.c > create mode 100644 i386/i386/cpuboot.S > > diff --git a/i386/i386/cpu_number.c b/i386/i386/cpu_number.c > new file mode 100644 > index 00000000..d4621669 > --- /dev/null > +++ b/i386/i386/cpu_number.c > @@ -0,0 +1,37 @@ > +/* > + * Copyright (c) 2022 Free Software Foundation, Inc. > + * > + * 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, see <http://www.gnu.org/licenses/>. > + */ > + > +#include <i386/cpu_number.h> > +#include <i386/apic.h> > +#include <i386/smp.h> > +#include <i386/cpu.h> > + > +#if NCPUS > 1 > +int cpu_number(void) > +{ > + int kernel_id; > + unsigned long flags; > + > + cpu_intr_save(&flags); > + > + kernel_id = apic_get_cpu_kernel_id(apic_get_current_cpu()); > + > + cpu_intr_restore(flags); > + > + return kernel_id; > Might be unrelated to this change, but will this be portable for x86_64? It seems we either should use uint32_t to store EFLAGS or use pushfq/popfq to get RFLAGS instead. +} > +#endif > diff --git a/i386/i386/cpuboot.S b/i386/i386/cpuboot.S > new file mode 100644 > index 00000000..4a5823be > --- /dev/null > +++ b/i386/i386/cpuboot.S > @@ -0,0 +1,164 @@ > +/* > + * Copyright (c) 2022 Free Software Foundation, Inc. + * > + * 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, see <http://www.gnu.org/licenses/>. > + */ > + > +#include <mach/machine/asm.h> > +#include <i386/i386asm.h> > +#include <i386/proc_reg.h> > +#include <i386/apic.h> > +#include <i386/cpu_number.h> > +#include <i386/seg.h> > + > +#define AP_BOOT_ADDR 0x7000 > +#define M(addr) (addr - apboot + AP_BOOT_ADDR) > +#define CR0_CLEAR_FLAGS_CACHE_ENABLE (CR0_CD | CR0_NW) > +#define CR0_SET_FLAGS (CR0_CLEAR_FLAGS_CACHE_ENABLE | CR0_PE) > +#define CR0_CLEAR_FLAGS (CR0_PG | CR0_AM | CR0_WP | CR0_NE | CR0_TS | > CR0_EM | CR0_MP) > +#define BOOT_CS 0x8 > +#define BOOT_DS 0x10 > + > +.text > + > +.align 16 > +apboot_idt_ptr: > + .long 0 > +.align 16 > + .word 0 > +apboot_gdt_descr: > + .word 3*8+7 > + .long apboot_gdt - KERNELBASE > +.align 16 > +apboot_gdt: > + /* NULL segment */ > + .quad 0 > + /* KERNEL_CS */ > + .word 0xffff /* Segment limit first 0-15 bits*/ > + .word (-KERNELBASE) & 0xffff /*Base first 0-15 bits*/ > + .byte ((-KERNELBASE) >> 16) & 0xff /*Base 16-23 bits */ > + .byte (ACC_P | ACC_CODE_R) /*Access byte */ > + .byte 0xcf /* High 4 bits */ > + .byte ((-KERNELBASE) >> 24) & 0xff /*Base 24-31 bits */ > + /* KERNEL_DS */ > + .word 0xffff /*Segment limit */ > + .word (-KERNELBASE) & 0xffff /*Base first 0-15 bits*/ > + .byte ((-KERNELBASE) >> 16) & 0xff > + .byte (ACC_P | ACC_DATA_W) /*Access byte*/ > + .byte 0xcf /* High 4 bits */ > + .byte ((-KERNELBASE) >> 24) & 0xff /*Base 24-31 bits */ > + > +.globl apboot, apbootend > +.align 16 > +.code16 > + > +apboot: > +_apboot: > + cli > + xorl %eax, %eax > + movl %eax, %cr3 > + mov %ax, %ds > + mov %ax, %es > + mov %ax, %fs > + mov %ax, %gs > + mov %ax, %ss > + > + lgdt M(gdt_descr_tmp) > + > + movl %cr0, %eax > + andl $~CR0_CLEAR_FLAGS, %eax > + orl $CR0_SET_FLAGS, %eax > + movl %eax, %cr0 > + > + ljmp $BOOT_CS, $M(0f) > +0: > + .code32 > + movw $BOOT_DS, %ax > + movw %ax, %ds > + movw %ax, %es > + movw %ax, %ss > + > + lgdtl apboot_gdt_descr - KERNELBASE > + ljmpl $KERNEL_CS, $1f > +1: > + xorl %eax, %eax > + movw %ax, %ds > + movw %ax, %es > + movw %ax, %fs > + movw %ax, %gs > + movw $KERNEL_DS, %ax > + movw %ax, %ds > + movw %ax, %es > + movw %ax, %fs > + movw %ax, %gs > + movw %ax, %ss > + > + /* Load null Interrupt descriptor table */ > + mov apboot_idt_ptr, %ebx > + lidt (%ebx) > + > + /* Enable local apic */ > + xorl %eax, %eax > + xorl %edx, %edx > + movl $APIC_MSR, %ecx > + rdmsr > + orl $APIC_MSR_ENABLE, %eax > + andl $(~APIC_MSR_BSP), %eax > + movl $APIC_MSR, %ecx > + wrmsr > + > + /* Load int_stack_top[cpu] -> esp */ > + CPU_NUMBER(%edx) > + movl CX(EXT(int_stack_top), %edx), %esp > + > + /* Ensure stack alignment */ > + andl $0xfffffff0, %esp > + > + /* Reset EFLAGS to a known state */ > + pushl $0 > + popfl > + > + /* Finish the cpu configuration */ > + call EXT(cpu_ap_main) > + > + /* NOT REACHED */ > + hlt > + > +.align 16 > + .word 0 > +gdt_descr_tmp: > + .short 3*8+7 > + .long M(gdt_tmp) > + > +.align 16 > +gdt_tmp: > + /* 0 */ > + .quad 0 > + /* BOOT_CS */ > + .word 0xffff > + .word 0x0000 > + .byte 0x00 > + .byte (ACC_P | ACC_CODE_R) > + .byte 0xcf > + .byte 0x00 > + /* BOOT_DS */ > + .word 0xffff > + .word 0x0000 > + .byte 0x00 > + .byte (ACC_P | ACC_DATA_W) > + .byte 0xcf > + .byte 0x00 > + > +_apbootend: > +apbootend: > -- > 2.34.1 > > > >
