mirror of
https://github.com/sigmasternchen/chaOS
synced 2025-03-15 05:38:54 +00:00
295 lines of unfinished scheduler
This commit is contained in:
parent
905c5b119c
commit
21a6e4d4a2
1 changed files with 297 additions and 0 deletions
297
scheduler.asm
Normal file
297
scheduler.asm
Normal file
|
@ -0,0 +1,297 @@
|
|||
;; scheduler
|
||||
;
|
||||
; Because we want want to be able use multible thread, we need a scheduler.
|
||||
; This scheduler is supposed to support up to 5 threads.
|
||||
;
|
||||
;;
|
||||
|
||||
;; global memory map
|
||||
;
|
||||
; $000
|
||||
; G P R
|
||||
; $01F
|
||||
; $020
|
||||
; I O R
|
||||
; $05F
|
||||
; $060
|
||||
; SRAM
|
||||
; $060
|
||||
; 192 bytes of scheduler memory
|
||||
; $102
|
||||
; $103
|
||||
; 1069 bytes of heap
|
||||
; $52F
|
||||
; $530
|
||||
; 639 bytes of stack
|
||||
; $62F
|
||||
; $62F
|
||||
;
|
||||
;;
|
||||
; this a ATmega16 specific
|
||||
|
||||
.equ heap_start = 0x103 ; starting address of heap
|
||||
.equ heap_end = 0x52F ; ending address of heap
|
||||
|
||||
.equ scheduler_global_active = 0x060 ; address of active-thread-cell
|
||||
.equ scheduler_global_number = 0x061 ; address of thread-number-cell
|
||||
.equ scheduler_global_maxnum = 0x004 ; maximal number of thread
|
||||
.equ scheduler_global_statu1 = 0x062 ; address of global-status-cell 1
|
||||
.equ scheduler_global_statu2 = 0x063 ; address of global-status-cell 2
|
||||
.equ scheduler_global_unused = 0x064 ; start address of unused block
|
||||
.equ scheduler_global_thread = 0x06B ; starting address of scheduler memory
|
||||
.equ scheduler_global_length = 0x026 ; length of thread in scheduler memory
|
||||
.equ scheduler_global_lastad = 0x102 ; last address of scheduler memory
|
||||
.equ scheduler_global_stacks = 0x530 ; start address of stacks
|
||||
|
||||
.equ scheduler_offset_stacks = 0x040 ; length of 1 stack
|
||||
.equ scheduler_offset_instat = 0x000 ; offset of internal sr in scheduler memory
|
||||
.equ scheduler_offset_instrh = 0x001 ; offset of iph in scheduler memory
|
||||
.equ scheduler_offset_instrl = 0x002 ; offset of ipl in scheduler memory
|
||||
.equ scheduler_offset_status = 0x003 ; offset of sr in scheduler memory
|
||||
.equ scheduler_offset_stackh = 0x004 ; offset of sph in scheduler memory
|
||||
.equ scheduler_offset_stackl = 0x005 ; offset of spl in scheduler memory
|
||||
.equ scheduler_offset_gprsta = 0x006 ; start offset of gpr in scheduler momory
|
||||
.equ scheduler_offset_gprend = 0x025 ; end offset of gpr in scheduler memory
|
||||
|
||||
;; scheduler memory
|
||||
;
|
||||
; We need to save the number of threads, the number of the active thread
|
||||
; and some other things.
|
||||
; For every thread we need to save:
|
||||
; - the instruction pointer (2 byte)
|
||||
; - the status register (1 byte)
|
||||
; - the stack pointer (2 byte)
|
||||
; - all 32 pgr
|
||||
; - plus 1 byte of status-values for the scheduler
|
||||
; => 38 bytes -> $26; starting at $06B
|
||||
; so: the sp of our thread x is calculated this way:
|
||||
; address = scheduler_global_thread + scheduler_global_length * x + scheduler_offset_stackp
|
||||
;
|
||||
;; scheduler memory map
|
||||
;
|
||||
; $060 active thread
|
||||
; $061 number of threads
|
||||
; $062 sr1 of scheduler
|
||||
; $063 sr2 of scheduler
|
||||
; // we still have 8 bytes of memory here
|
||||
; $06B
|
||||
; thread 0
|
||||
; $06B internal sr
|
||||
; $06C iph
|
||||
; $06D ipl
|
||||
; $06E sr
|
||||
; $06F sph
|
||||
; $070 spl
|
||||
; $071
|
||||
; gpr
|
||||
; $090
|
||||
; $090
|
||||
; $091
|
||||
; thread 1
|
||||
; $091 internal sr
|
||||
; $092 iph
|
||||
; $093 ipl
|
||||
; $094 sr
|
||||
; $095 sph
|
||||
; $096 spl
|
||||
; $097
|
||||
; gpr
|
||||
; $0B6
|
||||
; $0B6
|
||||
; $0B7
|
||||
; thread 2
|
||||
; $0B7 internal sr
|
||||
; $0B8 iph
|
||||
; $0B9 ipl
|
||||
; $0BA sr
|
||||
; $0BB sph
|
||||
; $0BC spl
|
||||
; $0BD
|
||||
; gpr
|
||||
; $0DC
|
||||
; $0DC
|
||||
; $0DD
|
||||
; thread 3
|
||||
; $0DD internal sr
|
||||
; $0DE iph
|
||||
; $0DF ipl
|
||||
; $0E0 sr
|
||||
; $0E1 sph
|
||||
; $0E2 spl
|
||||
; $0E3
|
||||
; gpr
|
||||
; $102
|
||||
; $102
|
||||
;
|
||||
;
|
||||
;; stacks
|
||||
;
|
||||
; As we should support 5 threads, we need 5 stacks.
|
||||
; For the calculation of the stack space (see global memory map) I assumed that
|
||||
; no stack will grow over 127 entries.
|
||||
; Our initial stackpointer for thread x will be calculated this way:
|
||||
; address = schedulder_global_stacks + scheduler_offset_stacks * x
|
||||
;
|
||||
;;
|
||||
|
||||
SchedulerInit:
|
||||
push r10
|
||||
in r10, sreg
|
||||
push r10
|
||||
push r11
|
||||
push xl
|
||||
push xh
|
||||
|
||||
; first we'll clear all scheduler memory cells
|
||||
ldi r10, 0
|
||||
ldi r11, low (scheduler_global_lastad)
|
||||
ldi xl, low (scheduler_global_active)
|
||||
ldi xh, high(scheduler_global_active)
|
||||
SchedulerInitLoop1: ; while(xl++ != r11)
|
||||
st x+, r10
|
||||
cp xl, r11
|
||||
brne SchedulerInitLoop1
|
||||
|
||||
; add main-thread
|
||||
call SchedulerAddThread
|
||||
|
||||
; start scheduler timer
|
||||
; we will use timer0 because we don't use all posibilities of timer2
|
||||
; TODO
|
||||
|
||||
pop xh
|
||||
pop xl
|
||||
pop r11
|
||||
pop r10
|
||||
out sreg, r10
|
||||
pop r10
|
||||
|
||||
ret
|
||||
|
||||
SchedulerAddThread:
|
||||
|
||||
|
||||
ret
|
||||
|
||||
SchedulerChangeThread:
|
||||
; puh, that will get hard
|
||||
; first we have to get the current instruction pointer
|
||||
|
||||
push xl
|
||||
push xh
|
||||
push r16
|
||||
in r16, sreg
|
||||
ldi xl, low (scheduler_global_unused)
|
||||
ldi xh, high(scheduler_global_unused)
|
||||
|
||||
st x+, r16 ; sreg is on unused[0]
|
||||
pop r16
|
||||
st x+, r16 ; r16 is on unused[1]
|
||||
pop r16
|
||||
st x+, r16 ; xh is on unused[2]
|
||||
pop r16
|
||||
st x+, r16 ; xl is on unused[3]
|
||||
|
||||
st x+, r17 ; r17 is on unused[4]
|
||||
st x+, r18 ; r18 is on unused[5]
|
||||
st x+, r19 ; r19 is on unused[6]
|
||||
st x+, r20 ; r19 is on unused[7]
|
||||
|
||||
pop r16 ; epic win !!!!!111
|
||||
pop r17
|
||||
; instruction pointer high is now in r16; low in r17
|
||||
; next we have to determine where we have to store our data
|
||||
|
||||
ldd r18 scheduler_global_active
|
||||
; number of current thread is now in r18
|
||||
; now we have to determine the start address of our thread memory
|
||||
|
||||
ldi xl, low (scheduler_global_thread)
|
||||
ldi xh, high(scheduler_global_thread)
|
||||
ldi r19, scheduler_global_length
|
||||
ldi r20, 0
|
||||
|
||||
SchedulerChangeThreadLoop1:
|
||||
cp r20, r18
|
||||
breq SchedulerChangeThreadLoop1End
|
||||
; we can do the following, because the address can not be greater
|
||||
; than 0x00FF (as you can see in the scheduler memory map)
|
||||
add xl, r19
|
||||
inc r20
|
||||
jmp SchedulerChangeThreadLoop1
|
||||
SchedulerChangeThreadLoop1End:
|
||||
|
||||
; x now contains the start address of our thread memory
|
||||
; let's copy some data
|
||||
|
||||
; this is, because we don't want to modify the status register
|
||||
ld r11, x+
|
||||
|
||||
; instruction pointer
|
||||
st x+, r16
|
||||
st x+, r17
|
||||
|
||||
; we need the status register, it's saved in unused[0]
|
||||
ldd r16, scheduler_global_unused
|
||||
st x+, r16
|
||||
|
||||
; so: the next step is the stack pointer
|
||||
in r16, sph
|
||||
st x+, r16
|
||||
in r16, spl
|
||||
st x+, r16
|
||||
|
||||
; whew. next we have to save all the pgrs
|
||||
st x+, r0
|
||||
st x+, r1
|
||||
st x+, r2
|
||||
st x+, r3
|
||||
st x+, r4
|
||||
st x+, r5
|
||||
st x+, r6
|
||||
st x+, r7
|
||||
st x+, r8
|
||||
st x+, r9
|
||||
st x+, r10
|
||||
st x+, r11
|
||||
st x+, r12
|
||||
st x+, r13
|
||||
st x+, r14
|
||||
st x+, r15
|
||||
ldd r16, (scheduler_global_unused + 1)
|
||||
st x+, r16
|
||||
ldd r16, (scheduler_global_unused + 4) ; this is r17
|
||||
st x+, r16
|
||||
ldd r16, (scheduler_global_unused + 5) ; this is r18
|
||||
st x+, r16
|
||||
ldd r16, (scheduler_global_unused + 6) ; this is r19
|
||||
st x+, r16
|
||||
ldd r16, (scheduler_global_unused + 7) ; this is r20
|
||||
st x+, r16
|
||||
st x+, r21
|
||||
st x+, r22
|
||||
st x+, r23
|
||||
st x+, r24
|
||||
st x+, r25
|
||||
ldd r16, (scheduler_global_unused + 3) ; this is xl
|
||||
st x+, r16
|
||||
ldd r16, (scheduler_global_unused + 2) ; this is xh
|
||||
st x+, r16
|
||||
st x+, yl
|
||||
st x+, yh
|
||||
st x+, zl
|
||||
st x+, zh
|
||||
|
||||
; soooo. we now have to get to know which is the next thread.
|
||||
; TODO:
|
||||
; - (r18 contains the nr of the active thread)
|
||||
; - r17 = scheduler_global_number
|
||||
; - if r18 = r17 then r18 = 0 else r18++
|
||||
; - cache ip
|
||||
; - cache sr
|
||||
; - replace sp
|
||||
; - do the same game in the other direction :D
|
||||
;
|
||||
; I'll write that later.
|
||||
|
||||
ret
|
Loading…
Reference in a new issue