RGBCube/serenity
1
Fork 0
mirror of https://github.com/RGBCube/serenity synced 2025-07-28 12:27:36 +00:00
Code Issues Activity Actions

Kernel: Implement software context switching and Processor structure

Browse source 
Moving certain globals into a new Processor structure for
each CPU allows us to eventually run an instance of the
scheduler on each CPU.
This commit is contained in:
Tom 2020-06-27 13:42:28 -06:00 • committed by Andreas Kling
parent 10407061d2
commit fb41d89384
22 changed files with 1002 additions and 513 deletions
Download patch file Download diff file Expand all files Collapse all files

49
Kernel/Arch/i386/Boot/boot.S
View file

@ -252,15 +252,6 @@ apic_ap_start:
mov %cs, %ax
mov %ax, %ds
/* Generate a new processor id. This is not the APIC id. We just
need a way to find ourselves a stack without stomping on other
APs that may be doing this concurrently. */
xor %ax, %ax
mov %ax, %bp
inc %ax
lock; xaddw %ax, %ds:(ap_cpu_id - apic_ap_start)(%bp) /* avoid relocation entries */
mov %ax, %bx
xor %ax, %ax
mov %ax, %sp
@ -281,14 +272,18 @@ apic_ap_start32:
mov %ax, %es
mov %ax, %fs
mov %ax, %gs
movl $0x8000, %ebp
/* generate a unique ap cpu id (0 means 1st ap, not bsp!) */
xorl %eax, %eax
incl %eax
lock; xaddl %eax, (ap_cpu_id - apic_ap_start)(%ebp) /* avoid relocation entries */
movl %eax, %esi
/* find our allocated stack based on the generated id */
andl 0x0000FFFF, %ebx
movl %ebx, %esi
movl (ap_cpu_init_stacks - apic_ap_start)(%ebp, %ebx, 4), %esp
movl (ap_cpu_init_stacks - apic_ap_start)(%ebp, %eax, 4), %esp
/* check if we support NX and enable it if we do */
movl $0x80000001, %eax
cpuid
@ -319,8 +314,8 @@ apic_ap_start32:
lgdt (ap_cpu_gdtr_initial2 - apic_ap_start + 0xc0008000)
/* jump above 3GB into our identity mapped area now */
ljmp $8, $(1f - apic_ap_start + 0xc0008000)
1:
ljmp $8, $(apic_ap_start32_2 - apic_ap_start + 0xc0008000)
apic_ap_start32_2:
/* flush the TLB */
movl %cr3, %eax
movl %eax, %cr3
@ -338,13 +333,20 @@ apic_ap_start32:
movl %eax, %cr0
movl (ap_cpu_init_cr4 - apic_ap_start)(%ebp), %eax
movl %eax, %cr4
/* push the Processor pointer this CPU is going to use */
movl (ap_cpu_init_processor_info_array - apic_ap_start)(%ebp), %eax
addl $0xc0000000, %eax
movl 0(%eax, %esi, 4), %eax
push %eax
/* push the cpu id, 0 representing the bsp and call into c++ */
incl %esi
push %esi
xor %ebp, %ebp
cld
/* push the arbitrary cpu id, 0 representing the bsp and call into c++ */
inc %esi
push %esi
/* We are in identity mapped P0x8000 and the BSP will unload this code
once all APs are initialized, so call init_ap but return to our
infinite loop */
@ -356,7 +358,7 @@ apic_ap_start32:
apic_ap_start_size:
.2byte end_apic_ap_start - apic_ap_start
ap_cpu_id:
.2byte 0x0
.4byte 0x0
ap_cpu_gdt:
/* null */
.8byte 0x0
@ -388,6 +390,9 @@ ap_cpu_init_cr3:
.global ap_cpu_init_cr4
ap_cpu_init_cr4:
.4byte 0x0 /* will be set at runtime */
.global ap_cpu_init_processor_info_array
ap_cpu_init_processor_info_array:
.4byte 0x0 /* will be set at runtime */
.global ap_cpu_init_stacks
ap_cpu_init_stacks:
/* array of allocated stack pointers */