diff options
Diffstat (limited to 'src')
-rw-r--r-- | src/arch/x86/isa/insts/romutil.py | 67 |
1 files changed, 30 insertions, 37 deletions
diff --git a/src/arch/x86/isa/insts/romutil.py b/src/arch/x86/isa/insts/romutil.py index 9645ee85d..2724637d1 100644 --- a/src/arch/x86/isa/insts/romutil.py +++ b/src/arch/x86/isa/insts/romutil.py @@ -59,25 +59,20 @@ def rom # Get the target CS descriptor using the selector in the gate # descriptor. # - srli t4, t1, 16, dataSize=8 - andi t5, t4, 0xF8, dataSize=8 - andi t0, t4, 0x4, flags=(EZF,), dataSize=2 + srli t10, t4, 16, dataSize=8 + andi t5, t10, 0xF8, dataSize=8 + andi t0, t10, 0x4, flags=(EZF,), dataSize=2 br rom_local_label("globalDescriptor"), flags=(CEZF,) ld t3, tsl, [1, t0, t5], dataSize=8, addressSize=8 br rom_local_label("processDescriptor") globalDescriptor: ld t3, tsg, [1, t0, t5], dataSize=8, addressSize=8 processDescriptor: - chks t4, t3, IntCSCheck, dataSize=8 - wrdl hs, t3, t4, dataSize=8 - - # Check that the target offset is in canonical form - wrdh t4, t1, t2, dataSize=8 - srli t4, t4, 47, dataSize=8 - addi t4, t4, 1, dataSize=8 - srli t4, t4, 1, dataSize=8 - or t4, t4, t4, flags=(EZF,), dataSize=2 - fault "new GeneralProtection(0)", flags=(nCEZF,) + chks t10, t3, IntCSCheck, dataSize=8 + wrdl hs, t3, t10, dataSize=8 + + # Stick the target offset in t9. + wrdh t9, t4, t2, dataSize=8 # @@ -85,27 +80,25 @@ processDescriptor: # # Record what we might set the stack selector to. - rdsel t6, ss - wrsel hs, t6 + rdsel t11, ss # Check if we're changing privelege level. At this point we can assume # we're going to a DPL that's less than or equal to the CPL. - rdattr t4, hs, dataSize=8 - srli t4, t4, 3, dataSize=8 - andi t4, t4, 3, dataSize=8 + rdattr t10, hs, dataSize=8 + srli t10, t10, 3, dataSize=8 + andi t10, t10, 3, dataSize=8 rdattr t5, cs, dataSize=8 srli t5, t5, 3, dataSize=8 - sub t5, t5, t4, dataSize=8 + sub t5, t5, t10, dataSize=8 andi t0, t5, 0x3, flags=(EZF,), dataSize=8 # We're going to change priviledge, so zero out the stack selector. We # need to let the IST have priority so we don't branch yet. - limm t4, 0 - wrsel hs, t4, flags=(nCEZF,) + wrsel t11, t0, flags=(nCEZF,) # Check the IST field of the gate descriptor - srli t4, t1, 32, dataSize=8 - andi t4, t4, 0x7, dataSize=8 - subi t0, t4, 1, flags=(ECF,), dataSize=8 + srli t10, t4, 32, dataSize=8 + andi t10, t10, 0x7, dataSize=8 + subi t0, t10, 1, flags=(ECF,), dataSize=8 br rom_local_label("istStackSwitch"), flags=(nCECF,) br rom_local_label("cplStackSwitch"), flags=(nCEZF,) @@ -134,42 +127,42 @@ stackSwitched: ## ## Point of no return. ## We're now going to irrevocably modify visible state. - ## Anything bad that's going to happen should have happened by now. + ## Anything bad that's going to happen should have happened by now or will + ## happen right now. ## + wrip t0, t9, dataSize=8 # # Build up the interrupt stack frame # + # Write out the contents of memory st t7, hs, [1, t0, t6], dataSize=8 limm t5, 0, dataSize=8 rdsel t5, cs, dataSize=2 st t5, hs, [1, t0, t6], 8, dataSize=8 - rflags t4, dataSize=8 - st t4, hs, [1, t0, t6], 16, dataSize=8 + rflags t10, dataSize=8 + st t10, hs, [1, t0, t6], 16, dataSize=8 st rsp, hs, [1, t0, t6], 24, dataSize=8 rdsel t5, ss, dataSize=2 st t5, hs, [1, t0, t6], 32, dataSize=8 # Set the stack segment mov rsp, rsp, t6, dataSize=8 - rdsel t7, hs, dataSize=2 - wrsel ss, t7, dataSize=2 + wrsel ss, t11, dataSize=2 # # Set up the target code segment # - srli t5, t1, 16, dataSize=8 + srli t5, t4, 16, dataSize=8 andi t5, t5, 0xFF, dataSize=8 wrdl cs, t3, t5, dataSize=8 wrsel cs, t5, dataSize=2 - wrdh t7, t1, t2, dataSize=8 - wrip t0, t7, dataSize=8 # - # Adjust rflags which is still in t4 from above + # Adjust rflags which is still in t10 from above # # Set IF to the lowest bit of the original gate type. @@ -177,16 +170,16 @@ stackSwitched: # Set the TF, NT, and RF bits. We'll flip them at the end. limm t6, (1 << 8) | (1 << 14) | (1 << 16) - or t4, t4, t6 - srli t5, t1, 40, dataSize=8 - srli t7, t4, 9, dataSize=8 + or t10, t10, t6 + srli t5, t4, 40, dataSize=8 + srli t7, t10, 9, dataSize=8 xor t5, t7, t5, dataSize=8 andi t5, t5, 1, dataSize=8 slli t5, t5, 9, dataSize=8 or t6, t5, t6, dataSize=8 # Put the results into rflags - wrflags t6, t4 + wrflags t6, t10 eret }; |