From 11753fd5bfa447d53ed3b8c81243d9063a20da4b Mon Sep 17 00:00:00 2001 From: Luke Kenneth Casson Leighton Date: Tue, 9 Mar 2021 12:38:08 +0000 Subject: [PATCH] move ISACaller RADIX MMU class to separate module --- src/soc/decoder/isa/caller.py | 433 +-------------------------- src/soc/decoder/isa/radixmmu.py | 504 ++++++++++++++++++++++++++++++++ 2 files changed, 506 insertions(+), 431 deletions(-) create mode 100644 src/soc/decoder/isa/radixmmu.py diff --git a/src/soc/decoder/isa/caller.py b/src/soc/decoder/isa/caller.py index 239865f9..6235c350 100644 --- a/src/soc/decoder/isa/caller.py +++ b/src/soc/decoder/isa/caller.py @@ -29,6 +29,8 @@ from soc.decoder.helpers import exts, gtu, ltu, undefined from soc.consts import PIb, MSRb # big-endian (PowerISA versions) from soc.decoder.power_svp64 import SVP64RM, decode_extra +from soc.decoder.isa.radixmmu import RADIX + from collections import namedtuple import math import sys @@ -78,413 +80,6 @@ def create_args(reglist, extra=None): return retval -# very quick, TODO move to SelectableInt utils later -def genmask(shift, size): - res = SelectableInt(0, size) - for i in range(size): - if i < shift: - res[size-1-i] = SelectableInt(1, 1) - return res - -""" - Get Root Page - - //Accessing 2nd double word of partition table (pate1) - //Ref: Power ISA Manual v3.0B, Book-III, section 5.7.6.1 - // PTCR Layout - // ==================================================== - // ----------------------------------------------- - // | /// | PATB | /// | PATS | - // ----------------------------------------------- - // 0 4 51 52 58 59 63 - // PATB[4:51] holds the base address of the Partition Table, - // right shifted by 12 bits. - // This is because the address of the Partition base is - // 4k aligned. Hence, the lower 12bits, which are always - // 0 are ommitted from the PTCR. - // - // Thus, The Partition Table Base is obtained by (PATB << 12) - // - // PATS represents the partition table size right-shifted by 12 bits. - // The minimal size of the partition table is 4k. - // Thus partition table size = (1 << PATS + 12). - // - // Partition Table - // ==================================================== - // 0 PATE0 63 PATE1 127 - // |----------------------|----------------------| - // | | | - // |----------------------|----------------------| - // | | | - // |----------------------|----------------------| - // | | | <-- effLPID - // |----------------------|----------------------| - // . - // . - // . - // |----------------------|----------------------| - // | | | - // |----------------------|----------------------| - // - // The effective LPID forms the index into the Partition Table. - // - // Each entry in the partition table contains 2 double words, PATE0, PATE1, - // corresponding to that partition. - // - // In case of Radix, The structure of PATE0 and PATE1 is as follows. - // - // PATE0 Layout - // ----------------------------------------------- - // |1|RTS1|/| RPDB | RTS2 | RPDS | - // ----------------------------------------------- - // 0 1 2 3 4 55 56 58 59 63 - // - // HR[0] : For Radix Page table, first bit should be 1. - // RTS1[1:2] : Gives one fragment of the Radix treesize - // RTS2[56:58] : Gives the second fragment of the Radix Tree size. - // RTS = (RTS1 << 3 + RTS2) + 31. - // - // RPDB[4:55] = Root Page Directory Base. - // RPDS = Logarithm of Root Page Directory Size right shifted by 3. - // Thus, Root page directory size = 1 << (RPDS + 3). - // Note: RPDS >= 5. - // - // PATE1 Layout - // ----------------------------------------------- - // |///| PRTB | // | PRTS | - // ----------------------------------------------- - // 0 3 4 51 52 58 59 63 - // - // PRTB[4:51] = Process Table Base. This is aligned to size. - // PRTS[59: 63] = Process Table Size right shifted by 12. - // Minimal size of the process table is 4k. - // Process Table Size = (1 << PRTS + 12). - // Note: PRTS <= 24. - // - // Computing the size aligned Process Table Base: - // table_base = (PRTB & ~((1 << PRTS) - 1)) << 12 - // Thus, the lower 12+PRTS bits of table_base will - // be zero. - - - //Ref: Power ISA Manual v3.0B, Book-III, section 5.7.6.2 - // - // Process Table - // ========================== - // 0 PRTE0 63 PRTE1 127 - // |----------------------|----------------------| - // | | | - // |----------------------|----------------------| - // | | | - // |----------------------|----------------------| - // | | | <-- effPID - // |----------------------|----------------------| - // . - // . - // . - // |----------------------|----------------------| - // | | | - // |----------------------|----------------------| - // - // The effective Process id (PID) forms the index into the Process Table. - // - // Each entry in the partition table contains 2 double words, PRTE0, PRTE1, - // corresponding to that process - // - // In case of Radix, The structure of PRTE0 and PRTE1 is as follows. - // - // PRTE0 Layout - // ----------------------------------------------- - // |/|RTS1|/| RPDB | RTS2 | RPDS | - // ----------------------------------------------- - // 0 1 2 3 4 55 56 58 59 63 - // - // RTS1[1:2] : Gives one fragment of the Radix treesize - // RTS2[56:58] : Gives the second fragment of the Radix Tree size. - // RTS = (RTS1 << 3 + RTS2) << 31, - // since minimal Radix Tree size is 4G. - // - // RPDB = Root Page Directory Base. - // RPDS = Root Page Directory Size right shifted by 3. - // Thus, Root page directory size = RPDS << 3. - // Note: RPDS >= 5. - // - // PRTE1 Layout - // ----------------------------------------------- - // | /// | - // ----------------------------------------------- - // 0 63 - // All bits are reserved. - - -""" - -# see qemu/target/ppc/mmu-radix64.c for reference -class RADIX: - def __init__(self, mem, caller): - self.mem = mem - self.caller = caller - - # cached page table stuff - self.pgtbl0 = 0 - self.pt0_valid = False - self.pgtbl3 = 0 - self.pt3_valid = False - - def __call__(self,*args, **kwargs): - print("TODO: implement RADIX.__call__()") - print(args) - print(kwargs) - return None - - def ld(self, address, width=8, swap=True, check_in_mem=False): - print("RADIX: ld from addr 0x%x width %d" % (address, width)) - dsisr = self.caller.spr[DEC_SPR.DSISR.value] - dar = self.caller.spr[DEC_SPR.DAR.value] - pidr = self.caller.spr[DEC_SPR.PIDR.value] - prtbl = self.caller.spr[DEC_SPR.PRTBL.value] - - pte = self._walk_tree() - # use pte to caclculate phys address - return self.mem.ld(address, width, swap, check_in_mem) - - # XXX set SPRs on error - - # TODO implement - def st(self, addr, v, width=8, swap=True): - print("RADIX: st to addr 0x%x width %d data %x" % (addr, width, v)) - dsisr = self.caller.spr[DEC_SPR.DSISR.value] - dar = self.caller.spr[DEC_SPR.DAR.value] - pidr = self.caller.spr[DEC_SPR.PIDR.value] - prtbl = self.caller.spr[DEC_SPR.PRTBL.value] - - # use pte to caclculate phys address (addr) - return self.mem.st(addr, v, width, swap) - - # XXX set SPRs on error - - def memassign(self, addr, sz, val): - print("memassign", addr, sz, val) - self.st(addr.value, val.value, sz, swap=False) - - def _next_level(self): - return True - ## DSISR_R_BADCONFIG - ## read_entry - ## DSISR_NOPTE - ## Prepare for next iteration - - def _walk_tree(self): - """walk tree - - // vaddr 64 Bit - // vaddr |-----------------------------------------------------| - // | Unused | Used | - // |-----------|-----------------------------------------| - // | 0000000 | usefulBits = X bits (typically 52) | - // |-----------|-----------------------------------------| - // | |<--Cursize---->| | - // | | Index | | - // | | into Page | | - // | | Directory | | - // |-----------------------------------------------------| - // | | - // V | - // PDE |---------------------------| | - // |V|L|//| NLB |///|NLS| | - // |---------------------------| | - // PDE = Page Directory Entry | - // [0] = V = Valid Bit | - // [1] = L = Leaf bit. If 0, then | - // [4:55] = NLB = Next Level Base | - // right shifted by 8 | - // [59:63] = NLS = Next Level Size | - // | NLS >= 5 | - // | V - // | |--------------------------| - // | | usfulBits = X-Cursize | - // | |--------------------------| - // |---------------------><--NLS-->| | - // | Index | | - // | into | | - // | PDE | | - // |--------------------------| - // | - // If the next PDE obtained by | - // (NLB << 8 + 8 * index) is a | - // nonleaf, then repeat the above. | - // | - // If the next PDE is a leaf, | - // then Leaf PDE structure is as | - // follows | - // | - // | - // Leaf PDE | - // |------------------------------| |----------------| - // |V|L|sw|//|RPN|sw|R|C|/|ATT|EAA| | usefulBits | - // |------------------------------| |----------------| - // [0] = V = Valid Bit | - // [1] = L = Leaf Bit = 1 if leaf | - // PDE | - // [2] = Sw = Sw bit 0. | - // [7:51] = RPN = Real Page Number, V - // real_page = RPN << 12 -------------> Logical OR - // [52:54] = Sw Bits 1:3 | - // [55] = R = Reference | - // [56] = C = Change V - // [58:59] = Att = Physical Address - // 0b00 = Normal Memory - // 0b01 = SAO - // 0b10 = Non Idenmpotent - // 0b11 = Tolerant I/O - // [60:63] = Encoded Access - // Authority - // - """ - # walk tree starts on prtbl - while True: - ret = self._next_level() - if ret: return ret - - def _decode_prte(self, data): - """PRTE0 Layout - ----------------------------------------------- - |/|RTS1|/| RPDB | RTS2 | RPDS | - ----------------------------------------------- - 0 1 2 3 4 55 56 58 59 63 - """ - # note that SelectableInt does big-endian! so the indices - # below *directly* match the spec, unlike microwatt which - # has to turn them around (to LE) - zero = SelectableInt(0, 1) - rts = selectconcat(zero, - data[56:59], # RTS2 - data[1:3], # RTS1 - ) - masksize = data[59:64] # RPDS - mbits = selectconcat(zero, masksize) - pgbase = selectconcat(data[8:56], # part of RPDB - SelectableInt(0, 16),) - - return (rts, mbits, pgbase) - - def _segment_check(self, addr, mbits, shift): - """checks segment valid - mbits := '0' & r.mask_size; - v.shift := r.shift + (31 - 12) - mbits; - nonzero := or(r.addr(61 downto 31) and not finalmask(30 downto 0)); - if r.addr(63) /= r.addr(62) or nonzero = '1' then - v.state := RADIX_FINISH; - v.segerror := '1'; - elsif mbits < 5 or mbits > 16 or mbits > (r.shift + (31 - 12)) then - v.state := RADIX_FINISH; - v.badtree := '1'; - else - v.state := RADIX_LOOKUP; - """ - # note that SelectableInt does big-endian! so the indices - # below *directly* match the spec, unlike microwatt which - # has to turn them around (to LE) - mask = genmask(shift, 44) - nonzero = addr[1:32] & mask[13:44] # mask 31 LSBs (BE numbered 13:44) - print ("RADIX _segment_check nonzero", bin(nonzero.value)) - print ("RADIX _segment_check addr[0-1]", addr[0].value, addr[1].value) - if addr[0] != addr[1] or nonzero == 1: - return "segerror" - limit = shift + (31 - 12) - if mbits < 5 or mbits > 16 or mbits > limit: - return "badtree" - new_shift = shift + (31 - 12) - mbits - return new_shift - - def _check_perms(self): - """check page permissions - -- test leaf bit - if data(62) = '1' then - -- check permissions and RC bits - perm_ok := '0'; - if r.priv = '1' or data(3) = '0' then - if r.iside = '0' then - perm_ok := data(1) or (data(2) and not r.store); - else - -- no IAMR, so no KUEP support for now - -- deny execute permission if cache inhibited - perm_ok := data(0) and not data(5); - end if; - end if; - rc_ok := data(8) and (data(7) or not r.store); - if perm_ok = '1' and rc_ok = '1' then - v.state := RADIX_LOAD_TLB; - else - v.state := RADIX_FINISH; - v.perm_err := not perm_ok; - -- permission error takes precedence over RC error - v.rc_error := perm_ok; - end if; - """ - - def _get_prtable_addr(self, shift, prtbl, addr, pid): - """ - if r.addr(63) = '1' then - effpid := x"00000000"; - else - effpid := r.pid; - end if; - x"00" & r.prtbl(55 downto 36) & - ((r.prtbl(35 downto 12) and not finalmask(23 downto 0)) or - (effpid(31 downto 8) and finalmask(23 downto 0))) & - effpid(7 downto 0) & "0000"; - """ - finalmask = genmask(shift, 44) - finalmask24 = finalmask[20:44] - if addr[0].value == 1: - effpid = SelectableInt(0, 32) - else: - effpid = self.pid[32:64] # TODO, check on this - zero16 = SelectableInt(0, 16) - zero4 = SelectableInt(0, 4) - res = selectconcat(zero16, - prtbl[8:28], # - (prtbl[28:52] & ~finalmask24) | # - (effpid[0:24] & finalmask24), # - effpid[24:32], - zero4 - ) - return res - - def _get_pgtable_addr(self, mask_size, pgbase, addrsh): - """ - x"00" & r.pgbase(55 downto 19) & - ((r.pgbase(18 downto 3) and not mask) or (addrsh and mask)) & - "000"; - """ - mask16 = genmask(mask_size+5, 16) - zero8 = SelectableInt(0, 8) - zero3 = SelectableInt(0, 3) - res = selectconcat(zero8, - pgbase[8:45], # - (prtbl[45:61] & ~mask16) | # - (addrsh & mask16), # - zero3 - ) - return res - - def _get_pte(self, shift, addr, pde): - """ - x"00" & - ((r.pde(55 downto 12) and not finalmask) or - (r.addr(55 downto 12) and finalmask)) - & r.pde(11 downto 0); - """ - finalmask = genmask(shift, 44) - zero8 = SelectableInt(0, 8) - res = selectconcat(zero8, - (pde[8:52] & ~finalmask) | # - (addr[8:52] & finalmask), # - pde[52:64], - ) - return res - class Mem: @@ -1535,27 +1130,3 @@ def inject(): return variable_injector -# very quick test of maskgen function (TODO, move to util later) -if __name__ == '__main__': - shift = SelectableInt(5, 6) - mask = genmask(shift, 43) - print (" mask", bin(mask.value)) - - mem = Mem(row_bytes=8) - mem = RADIX(mem, None) - # ----------------------------------------------- - # |/|RTS1|/| RPDB | RTS2 | RPDS | - # ----------------------------------------------- - # |0|1 2|3|4 55|56 58|59 63| - data = SelectableInt(0, 64) - data[1:3] = 0b01 - data[56:59] = 0b11 - data[59:64] = 0b01101 # mask - data[55] = 1 - (rts, mbits, pgbase) = mem._decode_prte(data) - print (" rts", bin(rts.value), rts.bits) - print (" mbits", bin(mbits.value), mbits.bits) - print (" pgbase", hex(pgbase.value), pgbase.bits) - addr = SelectableInt(0x1000, 64) - check = mem._segment_check(addr, mbits, shift) - print (" segment check", check) diff --git a/src/soc/decoder/isa/radixmmu.py b/src/soc/decoder/isa/radixmmu.py new file mode 100644 index 00000000..ecff5dda --- /dev/null +++ b/src/soc/decoder/isa/radixmmu.py @@ -0,0 +1,504 @@ +# SPDX-License-Identifier: LGPLv3+ +# Copyright (C) 2020, 2021 Luke Kenneth Casson Leighton +# Copyright (C) 2021 Tobias Platen +# Funded by NLnet http://nlnet.nl +"""core of the python-based POWER9 simulator + +this is part of a cycle-accurate POWER9 simulator. its primary purpose is +not speed, it is for both learning and educational purposes, as well as +a method of verifying the HDL. + +related bugs: + +* https://bugs.libre-soc.org/show_bug.cgi?id=604 +""" + +from nmigen.back.pysim import Settle +from functools import wraps +from copy import copy +from soc.decoder.orderedset import OrderedSet +from soc.decoder.selectable_int import (FieldSelectableInt, SelectableInt, + selectconcat) +from soc.decoder.power_enums import (spr_dict, spr_byname, XER_bits, + insns, MicrOp, In1Sel, In2Sel, In3Sel, + OutSel, CROutSel) + +from soc.decoder.power_enums import SPR as DEC_SPR + +from soc.decoder.helpers import exts, gtu, ltu, undefined +from soc.consts import PIb, MSRb # big-endian (PowerISA versions) +from soc.decoder.power_svp64 import SVP64RM, decode_extra + +from collections import namedtuple +import math +import sys + +instruction_info = namedtuple('instruction_info', + 'func read_regs uninit_regs write_regs ' + + 'special_regs op_fields form asmregs') + +special_sprs = { + 'LR': 8, + 'CTR': 9, + 'TAR': 815, + 'XER': 1, + 'VRSAVE': 256} + + +def swap_order(x, nbytes): + x = x.to_bytes(nbytes, byteorder='little') + x = int.from_bytes(x, byteorder='big', signed=False) + return x + + +REG_SORT_ORDER = { + # TODO (lkcl): adjust other registers that should be in a particular order + # probably CA, CA32, and CR + "RT": 0, + "RA": 0, + "RB": 0, + "RS": 0, + "CR": 0, + "LR": 0, + "CTR": 0, + "TAR": 0, + "CA": 0, + "CA32": 0, + "MSR": 0, + + "overflow": 1, +} + + +# very quick, TODO move to SelectableInt utils later +def genmask(shift, size): + res = SelectableInt(0, size) + for i in range(size): + if i < shift: + res[size-1-i] = SelectableInt(1, 1) + return res + +""" + Get Root Page + + //Accessing 2nd double word of partition table (pate1) + //Ref: Power ISA Manual v3.0B, Book-III, section 5.7.6.1 + // PTCR Layout + // ==================================================== + // ----------------------------------------------- + // | /// | PATB | /// | PATS | + // ----------------------------------------------- + // 0 4 51 52 58 59 63 + // PATB[4:51] holds the base address of the Partition Table, + // right shifted by 12 bits. + // This is because the address of the Partition base is + // 4k aligned. Hence, the lower 12bits, which are always + // 0 are ommitted from the PTCR. + // + // Thus, The Partition Table Base is obtained by (PATB << 12) + // + // PATS represents the partition table size right-shifted by 12 bits. + // The minimal size of the partition table is 4k. + // Thus partition table size = (1 << PATS + 12). + // + // Partition Table + // ==================================================== + // 0 PATE0 63 PATE1 127 + // |----------------------|----------------------| + // | | | + // |----------------------|----------------------| + // | | | + // |----------------------|----------------------| + // | | | <-- effLPID + // |----------------------|----------------------| + // . + // . + // . + // |----------------------|----------------------| + // | | | + // |----------------------|----------------------| + // + // The effective LPID forms the index into the Partition Table. + // + // Each entry in the partition table contains 2 double words, PATE0, PATE1, + // corresponding to that partition. + // + // In case of Radix, The structure of PATE0 and PATE1 is as follows. + // + // PATE0 Layout + // ----------------------------------------------- + // |1|RTS1|/| RPDB | RTS2 | RPDS | + // ----------------------------------------------- + // 0 1 2 3 4 55 56 58 59 63 + // + // HR[0] : For Radix Page table, first bit should be 1. + // RTS1[1:2] : Gives one fragment of the Radix treesize + // RTS2[56:58] : Gives the second fragment of the Radix Tree size. + // RTS = (RTS1 << 3 + RTS2) + 31. + // + // RPDB[4:55] = Root Page Directory Base. + // RPDS = Logarithm of Root Page Directory Size right shifted by 3. + // Thus, Root page directory size = 1 << (RPDS + 3). + // Note: RPDS >= 5. + // + // PATE1 Layout + // ----------------------------------------------- + // |///| PRTB | // | PRTS | + // ----------------------------------------------- + // 0 3 4 51 52 58 59 63 + // + // PRTB[4:51] = Process Table Base. This is aligned to size. + // PRTS[59: 63] = Process Table Size right shifted by 12. + // Minimal size of the process table is 4k. + // Process Table Size = (1 << PRTS + 12). + // Note: PRTS <= 24. + // + // Computing the size aligned Process Table Base: + // table_base = (PRTB & ~((1 << PRTS) - 1)) << 12 + // Thus, the lower 12+PRTS bits of table_base will + // be zero. + + + //Ref: Power ISA Manual v3.0B, Book-III, section 5.7.6.2 + // + // Process Table + // ========================== + // 0 PRTE0 63 PRTE1 127 + // |----------------------|----------------------| + // | | | + // |----------------------|----------------------| + // | | | + // |----------------------|----------------------| + // | | | <-- effPID + // |----------------------|----------------------| + // . + // . + // . + // |----------------------|----------------------| + // | | | + // |----------------------|----------------------| + // + // The effective Process id (PID) forms the index into the Process Table. + // + // Each entry in the partition table contains 2 double words, PRTE0, PRTE1, + // corresponding to that process + // + // In case of Radix, The structure of PRTE0 and PRTE1 is as follows. + // + // PRTE0 Layout + // ----------------------------------------------- + // |/|RTS1|/| RPDB | RTS2 | RPDS | + // ----------------------------------------------- + // 0 1 2 3 4 55 56 58 59 63 + // + // RTS1[1:2] : Gives one fragment of the Radix treesize + // RTS2[56:58] : Gives the second fragment of the Radix Tree size. + // RTS = (RTS1 << 3 + RTS2) << 31, + // since minimal Radix Tree size is 4G. + // + // RPDB = Root Page Directory Base. + // RPDS = Root Page Directory Size right shifted by 3. + // Thus, Root page directory size = RPDS << 3. + // Note: RPDS >= 5. + // + // PRTE1 Layout + // ----------------------------------------------- + // | /// | + // ----------------------------------------------- + // 0 63 + // All bits are reserved. + + +""" + +# see qemu/target/ppc/mmu-radix64.c for reference +class RADIX: + def __init__(self, mem, caller): + self.mem = mem + self.caller = caller + + # cached page table stuff + self.pgtbl0 = 0 + self.pt0_valid = False + self.pgtbl3 = 0 + self.pt3_valid = False + + def __call__(self,*args, **kwargs): + print("TODO: implement RADIX.__call__()") + print(args) + print(kwargs) + return None + + def ld(self, address, width=8, swap=True, check_in_mem=False): + print("RADIX: ld from addr 0x%x width %d" % (address, width)) + dsisr = self.caller.spr[DEC_SPR.DSISR.value] + dar = self.caller.spr[DEC_SPR.DAR.value] + pidr = self.caller.spr[DEC_SPR.PIDR.value] + prtbl = self.caller.spr[DEC_SPR.PRTBL.value] + + pte = self._walk_tree() + # use pte to caclculate phys address + return self.mem.ld(address, width, swap, check_in_mem) + + # XXX set SPRs on error + + # TODO implement + def st(self, addr, v, width=8, swap=True): + print("RADIX: st to addr 0x%x width %d data %x" % (addr, width, v)) + dsisr = self.caller.spr[DEC_SPR.DSISR.value] + dar = self.caller.spr[DEC_SPR.DAR.value] + pidr = self.caller.spr[DEC_SPR.PIDR.value] + prtbl = self.caller.spr[DEC_SPR.PRTBL.value] + + # use pte to caclculate phys address (addr) + return self.mem.st(addr, v, width, swap) + + # XXX set SPRs on error + + def memassign(self, addr, sz, val): + print("memassign", addr, sz, val) + self.st(addr.value, val.value, sz, swap=False) + + def _next_level(self): + return True + ## DSISR_R_BADCONFIG + ## read_entry + ## DSISR_NOPTE + ## Prepare for next iteration + + def _walk_tree(self): + """walk tree + + // vaddr 64 Bit + // vaddr |-----------------------------------------------------| + // | Unused | Used | + // |-----------|-----------------------------------------| + // | 0000000 | usefulBits = X bits (typically 52) | + // |-----------|-----------------------------------------| + // | |<--Cursize---->| | + // | | Index | | + // | | into Page | | + // | | Directory | | + // |-----------------------------------------------------| + // | | + // V | + // PDE |---------------------------| | + // |V|L|//| NLB |///|NLS| | + // |---------------------------| | + // PDE = Page Directory Entry | + // [0] = V = Valid Bit | + // [1] = L = Leaf bit. If 0, then | + // [4:55] = NLB = Next Level Base | + // right shifted by 8 | + // [59:63] = NLS = Next Level Size | + // | NLS >= 5 | + // | V + // | |--------------------------| + // | | usfulBits = X-Cursize | + // | |--------------------------| + // |---------------------><--NLS-->| | + // | Index | | + // | into | | + // | PDE | | + // |--------------------------| + // | + // If the next PDE obtained by | + // (NLB << 8 + 8 * index) is a | + // nonleaf, then repeat the above. | + // | + // If the next PDE is a leaf, | + // then Leaf PDE structure is as | + // follows | + // | + // | + // Leaf PDE | + // |------------------------------| |----------------| + // |V|L|sw|//|RPN|sw|R|C|/|ATT|EAA| | usefulBits | + // |------------------------------| |----------------| + // [0] = V = Valid Bit | + // [1] = L = Leaf Bit = 1 if leaf | + // PDE | + // [2] = Sw = Sw bit 0. | + // [7:51] = RPN = Real Page Number, V + // real_page = RPN << 12 -------------> Logical OR + // [52:54] = Sw Bits 1:3 | + // [55] = R = Reference | + // [56] = C = Change V + // [58:59] = Att = Physical Address + // 0b00 = Normal Memory + // 0b01 = SAO + // 0b10 = Non Idenmpotent + // 0b11 = Tolerant I/O + // [60:63] = Encoded Access + // Authority + // + """ + # walk tree starts on prtbl + while True: + ret = self._next_level() + if ret: return ret + + def _decode_prte(self, data): + """PRTE0 Layout + ----------------------------------------------- + |/|RTS1|/| RPDB | RTS2 | RPDS | + ----------------------------------------------- + 0 1 2 3 4 55 56 58 59 63 + """ + # note that SelectableInt does big-endian! so the indices + # below *directly* match the spec, unlike microwatt which + # has to turn them around (to LE) + zero = SelectableInt(0, 1) + rts = selectconcat(zero, + data[56:59], # RTS2 + data[1:3], # RTS1 + ) + masksize = data[59:64] # RPDS + mbits = selectconcat(zero, masksize) + pgbase = selectconcat(data[8:56], # part of RPDB + SelectableInt(0, 16),) + + return (rts, mbits, pgbase) + + def _segment_check(self, addr, mbits, shift): + """checks segment valid + mbits := '0' & r.mask_size; + v.shift := r.shift + (31 - 12) - mbits; + nonzero := or(r.addr(61 downto 31) and not finalmask(30 downto 0)); + if r.addr(63) /= r.addr(62) or nonzero = '1' then + v.state := RADIX_FINISH; + v.segerror := '1'; + elsif mbits < 5 or mbits > 16 or mbits > (r.shift + (31 - 12)) then + v.state := RADIX_FINISH; + v.badtree := '1'; + else + v.state := RADIX_LOOKUP; + """ + # note that SelectableInt does big-endian! so the indices + # below *directly* match the spec, unlike microwatt which + # has to turn them around (to LE) + mask = genmask(shift, 44) + nonzero = addr[1:32] & mask[13:44] # mask 31 LSBs (BE numbered 13:44) + print ("RADIX _segment_check nonzero", bin(nonzero.value)) + print ("RADIX _segment_check addr[0-1]", addr[0].value, addr[1].value) + if addr[0] != addr[1] or nonzero == 1: + return "segerror" + limit = shift + (31 - 12) + if mbits < 5 or mbits > 16 or mbits > limit: + return "badtree" + new_shift = shift + (31 - 12) - mbits + return new_shift + + def _check_perms(self): + """check page permissions + -- test leaf bit + if data(62) = '1' then + -- check permissions and RC bits + perm_ok := '0'; + if r.priv = '1' or data(3) = '0' then + if r.iside = '0' then + perm_ok := data(1) or (data(2) and not r.store); + else + -- no IAMR, so no KUEP support for now + -- deny execute permission if cache inhibited + perm_ok := data(0) and not data(5); + end if; + end if; + rc_ok := data(8) and (data(7) or not r.store); + if perm_ok = '1' and rc_ok = '1' then + v.state := RADIX_LOAD_TLB; + else + v.state := RADIX_FINISH; + v.perm_err := not perm_ok; + -- permission error takes precedence over RC error + v.rc_error := perm_ok; + end if; + """ + + def _get_prtable_addr(self, shift, prtbl, addr, pid): + """ + if r.addr(63) = '1' then + effpid := x"00000000"; + else + effpid := r.pid; + end if; + x"00" & r.prtbl(55 downto 36) & + ((r.prtbl(35 downto 12) and not finalmask(23 downto 0)) or + (effpid(31 downto 8) and finalmask(23 downto 0))) & + effpid(7 downto 0) & "0000"; + """ + finalmask = genmask(shift, 44) + finalmask24 = finalmask[20:44] + if addr[0].value == 1: + effpid = SelectableInt(0, 32) + else: + effpid = self.pid[32:64] # TODO, check on this + zero16 = SelectableInt(0, 16) + zero4 = SelectableInt(0, 4) + res = selectconcat(zero16, + prtbl[8:28], # + (prtbl[28:52] & ~finalmask24) | # + (effpid[0:24] & finalmask24), # + effpid[24:32], + zero4 + ) + return res + + def _get_pgtable_addr(self, mask_size, pgbase, addrsh): + """ + x"00" & r.pgbase(55 downto 19) & + ((r.pgbase(18 downto 3) and not mask) or (addrsh and mask)) & + "000"; + """ + mask16 = genmask(mask_size+5, 16) + zero8 = SelectableInt(0, 8) + zero3 = SelectableInt(0, 3) + res = selectconcat(zero8, + pgbase[8:45], # + (prtbl[45:61] & ~mask16) | # + (addrsh & mask16), # + zero3 + ) + return res + + def _get_pte(self, shift, addr, pde): + """ + x"00" & + ((r.pde(55 downto 12) and not finalmask) or + (r.addr(55 downto 12) and finalmask)) + & r.pde(11 downto 0); + """ + finalmask = genmask(shift, 44) + zero8 = SelectableInt(0, 8) + res = selectconcat(zero8, + (pde[8:52] & ~finalmask) | # + (addr[8:52] & finalmask), # + pde[52:64], + ) + return res + + +# very quick test of maskgen function (TODO, move to util later) +if __name__ == '__main__': + shift = SelectableInt(5, 6) + mask = genmask(shift, 43) + print (" mask", bin(mask.value)) + + mem = Mem(row_bytes=8) + mem = RADIX(mem, None) + # ----------------------------------------------- + # |/|RTS1|/| RPDB | RTS2 | RPDS | + # ----------------------------------------------- + # |0|1 2|3|4 55|56 58|59 63| + data = SelectableInt(0, 64) + data[1:3] = 0b01 + data[56:59] = 0b11 + data[59:64] = 0b01101 # mask + data[55] = 1 + (rts, mbits, pgbase) = mem._decode_prte(data) + print (" rts", bin(rts.value), rts.bits) + print (" mbits", bin(mbits.value), mbits.bits) + print (" pgbase", hex(pgbase.value), pgbase.bits) + addr = SelectableInt(0x1000, 64) + check = mem._segment_check(addr, mbits, shift) + print (" segment check", check) -- 2.30.2