Restriction 30 : Hw_Mtpr And Hw_Mfpr To The Cbox Csr - Compaq 21264 Hardware Reference Manual

Restriction 30 : HW_MTPR and HW_MFPR to the Cbox CSR

ALIGN_FETCH_BLOCK
sys__cbox:
mb
hw_mfpr p6, EV6__I_CTL
lda
and
sbe_off_offset = <sys__cbox_sbe_off_done - sys__cbox_sbe_off>
hw_mtpr p4, EV6__I_CTL
br
sys__cbox_sbe_off:
addq
bsr
ALIGN_FETCH_BLOCK <^x47FF041F>; align
hw_mtpr r31, EV6__IC_FLUSH
bne
PVC_JSR sbe_off
hw_ret_stall (p6)
PVC_JSR sbe_off, dest=1
sys__cbox_sbe_off_done:
br
ALIGN_CACHE_BLOCK
sys__cbox_over1:
addq
addq
br
sys__cbox_touch1:
br
sys__cbox_over2:
hw_mtpr r31, EV6__SHIFT_CONTROL
subq
br
sys__cbox_touch2:
br
sys__cbox_over3:
hw_mtpr r31, <EV6__MM_STAT ! 64 >
bis
br
sys__cbox_touch3:
br
sys__cbox_over4:
hw_mfpr p4, EV6__DATA
bis
br
sys__cbox_touch4:
br
sys__cbox_over5:
and
addq
br
sys__cbox_touch5:
br
PALcode Restrictions and Guidelines
D–16
p4, ^xFCFF(r31)
p6, p4, p4
p6, sys__cbox_sbe_off
p6, #<sbe_off_offset+1>, p6
r31, .
r31, .
r31, sys__cbox_touch1
r31, #11, p6
r31, r31, p7
r31, sys__cbox_over2
r31, sys__cbox_touch2
p6, #1, p6
r31, sys__cbox_over3
r31, sys__cbox_touch3
p5, #1, p5
r31, sys__cbox_over4
r31, sys__cbox_touch4
r31, r31, r31
r31, sys__cbox_over5
r31, sys__cbox_touch5
p4, #^x3F, p4
p4, p7, p7
r31, sys__cbox_over6
r31, sys__cbox_touch6
; quiet the dstream
; (4,0L) get i_ctl
; mask for clearing SBE bits
; clear SBE bits
; (4,0L) write new i_ctl
; past stall in palmode
; stack push
; (4,0L) eliminate prefetches
; pvc #24
; synch and flush
; use ret, pop stack
; br stops predictor
; now pull in the next block
; block 1
; initialize shift count (11x)
; initialize shift data
; go to block 2
;
; touch block 2
; block 2
; (6,0L) shift in 6 bits
; decrement shift count
; go to block 3
;
; touch block 3
; block 3
; (6,0L) wait for shift
; return in pal mode
; go to block 4
;
; touch block 4
; block 4
; (6,0L) read cbox data
; nop
; go to block 5
;
; touch block 5
; block 5
; clean to <5:0>
; accumulate shift data
; go to block 6
;
; touch block 6
Alpha 21264/EV67 Hardware Reference Manual