riscv/rocket-chip
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cleanup, lots of minor fixes, added more PCR regs (COREID, NUMCORES), parameterized BTB

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This commit is contained in:
Rimas Avizienis 2011-11-10 11:26:13 -08:00
parent 4bd0263a4a
commit f86d5b1334
9 changed files with 119 additions and 109 deletions
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6
rocket/src/main/scala/consts.scala
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@ -146,15 +146,19 @@ object Constants
val PCR_COUNT = UFix( 4, 5); val PCR_COUNT = UFix( 4, 5);
val PCR_COMPARE = UFix( 5, 5); val PCR_COMPARE = UFix( 5, 5);
val PCR_CAUSE = UFix( 6, 5); val PCR_CAUSE = UFix( 6, 5);
val PCR_IPI = UFix( 7, 5);
val PCR_MEMSIZE = UFix( 8, 5); val PCR_MEMSIZE = UFix( 8, 5);
val PCR_PTBR = UFix( 9, 5); val PCR_PTBR = UFix( 9, 5);
val PCR_LOG = UFix(10, 5); val PCR_COREID = UFix(10, 5);
val PCR_NUMCORES = UFix(12, 5);
val PCR_TOHOST = UFix(16, 5); val PCR_TOHOST = UFix(16, 5);
val PCR_FROMHOST = UFix(17, 5); val PCR_FROMHOST = UFix(17, 5);
val PCR_CONSOLE = UFix(18, 5); val PCR_CONSOLE = UFix(18, 5);
val PCR_K0 = UFix(24, 5); val PCR_K0 = UFix(24, 5);
val PCR_K1 = UFix(25, 5); val PCR_K1 = UFix(25, 5);
val COREID = 0;
val NUMCORES = 1;
val PADDR_BITS = 40; val PADDR_BITS = 40;
val VADDR_BITS = 43; val VADDR_BITS = 43;
val PGIDX_BITS = 13; val PGIDX_BITS = 13;

1
rocket/src/main/scala/cpu.scala
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@ -7,7 +7,6 @@ import Constants._;
class ioDebug(view: List[String] = null) extends Bundle(view) class ioDebug(view: List[String] = null) extends Bundle(view)
{ {
val error_mode = Bool('output); val error_mode = Bool('output);
val log_control = Bool('output);
val id_valid = Bool('output); val id_valid = Bool('output);
val ex_valid = Bool('output); val ex_valid = Bool('output);
val mem_valid = Bool('output); val mem_valid = Bool('output);

2
rocket/src/main/scala/dcache.scala
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@ -17,7 +17,7 @@ class ioDmem(view: List[String] = null) extends Bundle(view) {
val resp_miss = Bool('output); val resp_miss = Bool('output);
val resp_val = Bool('output); val resp_val = Bool('output);
val resp_data = Bits(64, 'output); val resp_data = Bits(64, 'output);
val resp_tag = Bits(13, 'output); val resp_tag = Bits(12, 'output);
} }
// interface between D$ and next level in memory hierarchy // interface between D$ and next level in memory hierarchy

6
rocket/src/main/scala/dpath.scala
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@ -11,7 +11,7 @@ class ioDpathDmem extends Bundle()
val req_tag = UFix(5, 'output); val req_tag = UFix(5, 'output);
val req_data = Bits(64, 'output); val req_data = Bits(64, 'output);
val resp_val = Bool('input); val resp_val = Bool('input);
val resp_tag = Bits(13, 'input); // FIXME: MSB is ignored val resp_tag = Bits(12, 'input); // FIXME: MSB is ignored
val resp_data = Bits(64, 'input); val resp_data = Bits(64, 'input);
} }
@ -35,7 +35,8 @@ class rocketDpath extends Component
{ {
val io = new ioDpathAll(); val io = new ioDpathAll();
val btb = new rocketDpathBTB(); val btb = new rocketDpathBTB(8); // # of entries in BTB
val if_btb_target = btb.io.target; val if_btb_target = btb.io.target;
val pcr = new rocketDpathPCR(); val pcr = new rocketDpathPCR();
@ -357,7 +358,6 @@ class rocketDpath extends Component
io.ctrl.status := pcr.io.status; io.ctrl.status := pcr.io.status;
io.ptbr := pcr.io.ptbr; io.ptbr := pcr.io.ptbr;
io.debug.error_mode := pcr.io.debug.error_mode; io.debug.error_mode := pcr.io.debug.error_mode;
io.debug.log_control := pcr.io.debug.log_control;
// branch resolution logic // branch resolution logic
io.ctrl.br_eq := (ex_reg_rs1 === ex_reg_rs2); io.ctrl.br_eq := (ex_reg_rs1 === ex_reg_rs2);

95
rocket/src/main/scala/dpath_util.scala
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@ -4,6 +4,7 @@ package Top
import Chisel._; import Chisel._;
import Node._; import Node._;
import Constants._; import Constants._;
import scala.math._;
class ioDpathBTB extends Bundle() class ioDpathBTB extends Bundle()
{ {
@ -15,17 +16,34 @@ class ioDpathBTB extends Bundle()
val correct_target = UFix(VADDR_BITS, 'input); val correct_target = UFix(VADDR_BITS, 'input);
} }
class rocketDpathBTB extends Component // basic direct-mapped branch target buffer
class rocketDpathBTB(entries: Int) extends Component
{ {
override val io = new ioDpathBTB(); val io = new ioDpathBTB();
val rst_lwlr_pf = Mem(4, io.wen, io.correct_pc4(3, 2), UFix(1, 1), resetVal = UFix(0, 1));
val lwlr_pf = Mem(4, io.wen, io.correct_pc4(3, 2),
Cat(io.correct_pc4(VADDR_BITS-1,4), io.correct_target(VADDR_BITS-1,2)), resetVal = UFix(0, 1));
val is_val = rst_lwlr_pf(io.current_pc4(3, 2));
val tag_target = lwlr_pf(io.current_pc4(3, 2));
io.hit := (is_val & (tag_target(2*VADDR_BITS-7,VADDR_BITS-2) === io.current_pc4(VADDR_BITS-1, 4))).toBool; val addr_bits = ceil(log10(entries)/log10(2)).toInt;
io.target := Cat(tag_target(VADDR_BITS-3, 0), Bits(0,2)).toUFix; val idxlsb = 2;
val idxmsb = idxlsb+addr_bits-1;
val tagmsb = (VADDR_BITS-idxmsb-1)+(VADDR_BITS-idxlsb)-1;
val taglsb = (VADDR_BITS-idxlsb);
val rst_lwlr_pf = Mem(entries, io.wen, io.correct_pc4(idxmsb,idxlsb), UFix(1,1), resetVal = UFix(0,1));
val lwlr_pf = Mem(entries, io.wen, io.correct_pc4(idxmsb,idxlsb),
Cat(io.correct_pc4(VADDR_BITS-1,idxmsb+1), io.correct_target(VADDR_BITS-1,idxlsb)), resetVal = UFix(0,1));
val is_val = rst_lwlr_pf(io.current_pc4(idxmsb,idxlsb));
val tag_target = lwlr_pf(io.current_pc4(idxmsb, idxlsb));
io.hit := (is_val & (tag_target(tagmsb,taglsb) === io.current_pc4(VADDR_BITS-1, idxmsb+1))).toBool;
io.target := Cat(tag_target(taglsb-1, 0), Bits(0,idxlsb)).toUFix;
// val rst_lwlr_pf = Mem(entries, io.wen, io.correct_pc4(3, 2), UFix(1, 1), resetVal = UFix(0, 1));
// val lwlr_pf = Mem(entries, io.wen, io.correct_pc4(3, 2),
// Cat(io.correct_pc4(VADDR_BITS-1,4), io.correct_target(VADDR_BITS-1,2)), resetVal = UFix(0, 1));
// val is_val = rst_lwlr_pf(io.current_pc4(3, 2));
// val tag_target = lwlr_pf(io.current_pc4(3, 2));
//
// io.hit := (is_val & (tag_target(2*VADDR_BITS-7,VADDR_BITS-2) === io.current_pc4(VADDR_BITS-1, 4))).toBool;
// io.target := Cat(tag_target(VADDR_BITS-3, 0), Bits(0,2)).toUFix;
} }
class ioDpathPCR extends Bundle() class ioDpathPCR extends Bundle()
@ -49,22 +67,20 @@ class ioDpathPCR extends Bundle()
class rocketDpathPCR extends Component class rocketDpathPCR extends Component
{ {
val io = new ioDpathPCR(); val io = new ioDpathPCR();
val w = 32;
val reg_epc = Reg(resetVal = UFix(0, VADDR_BITS)); val reg_epc = Reg(resetVal = UFix(0, VADDR_BITS));
val reg_badvaddr = Reg(resetVal = UFix(0, VADDR_BITS)); val reg_badvaddr = Reg(resetVal = UFix(0, VADDR_BITS));
val reg_ebase = Reg(resetVal = UFix(0, VADDR_BITS)); val reg_ebase = Reg(resetVal = UFix(0, VADDR_BITS));
val reg_count = Reg(resetVal = Bits(0, w)); val reg_count = Reg(resetVal = Bits(0, 32));
val reg_compare = Reg(resetVal = Bits(0, w)); val reg_compare = Reg(resetVal = Bits(0, 32));
val reg_cause = Reg(resetVal = Bits(0, 5)); val reg_cause = Reg(resetVal = Bits(0, 5));
val reg_tohost = Reg(resetVal = Bits(0, w)); val reg_tohost = Reg(resetVal = Bits(0, 32));
val reg_fromhost = Reg(resetVal = Bits(0, w)); val reg_fromhost = Reg(resetVal = Bits(0, 32));
val reg_k0 = Reg(resetVal = Bits(0, 2*w)); val reg_k0 = Reg(resetVal = Bits(0, 64));
val reg_k1 = Reg(resetVal = Bits(0, 2*w)); val reg_k1 = Reg(resetVal = Bits(0, 64));
val reg_ptbr = Reg(resetVal = UFix(0, PADDR_BITS)); val reg_ptbr = Reg(resetVal = UFix(0, PADDR_BITS));
val reg_error_mode = Reg(resetVal = Bool(false)); val reg_error_mode = Reg(resetVal = Bool(false));
val reg_log_control = Reg(resetVal = Bool(false));
val reg_status_vm = Reg(resetVal = Bool(false)); val reg_status_vm = Reg(resetVal = Bool(false));
val reg_status_im = Reg(resetVal = Bits(0,8)); val reg_status_im = Reg(resetVal = Bits(0,8));
val reg_status_sx = Reg(resetVal = Bool(true)); val reg_status_sx = Reg(resetVal = Bool(true));
@ -81,19 +97,18 @@ class rocketDpathPCR extends Component
io.status := Cat(reg_status_vm, reg_status_im, reg_status); io.status := Cat(reg_status_vm, reg_status_im, reg_status);
io.evec := reg_ebase; io.evec := reg_ebase;
io.ptbr := reg_ptbr; io.ptbr := reg_ptbr;
io.host.to := Mux(io.host.from_wen, Bits(0, w), reg_tohost); io.host.to := Mux(io.host.from_wen, Bits(0,32), reg_tohost);
io.debug.error_mode := reg_error_mode; io.debug.error_mode := reg_error_mode;
io.debug.log_control := reg_log_control;
io.r.data := rdata; io.r.data := rdata;
when (io.host.from_wen) { when (io.host.from_wen) {
reg_tohost <== Bits(0, w); reg_tohost <== Bits(0,32);
reg_fromhost <== io.host.from; reg_fromhost <== io.host.from;
} }
otherwise { otherwise {
when (!io.exception && io.w.en && (io.w.addr === PCR_TOHOST)) { when (!io.exception && io.w.en && (io.w.addr === PCR_TOHOST)) {
reg_tohost <== io.w.data(w-1, 0); reg_tohost <== io.w.data(31,0);
reg_fromhost <== Bits(0, w); reg_fromhost <== Bits(0,32);
} }
} }
@ -133,33 +148,33 @@ class rocketDpathPCR extends Component
when (io.w.addr === PCR_EPC) { reg_epc <== io.w.data(VADDR_BITS-1,0).toUFix; } when (io.w.addr === PCR_EPC) { reg_epc <== io.w.data(VADDR_BITS-1,0).toUFix; }
when (io.w.addr === PCR_BADVADDR) { reg_badvaddr <== io.w.data(VADDR_BITS-1,0).toUFix; } when (io.w.addr === PCR_BADVADDR) { reg_badvaddr <== io.w.data(VADDR_BITS-1,0).toUFix; }
when (io.w.addr === PCR_EVEC) { reg_ebase <== io.w.data(VADDR_BITS-1,0).toUFix; } when (io.w.addr === PCR_EVEC) { reg_ebase <== io.w.data(VADDR_BITS-1,0).toUFix; }
when (io.w.addr === PCR_COUNT) { reg_count <== io.w.data(w-1,0); } when (io.w.addr === PCR_COUNT) { reg_count <== io.w.data(31,0); }
when (io.w.addr === PCR_COMPARE) { reg_compare <== io.w.data(w-1,0); } when (io.w.addr === PCR_COMPARE) { reg_compare <== io.w.data(31,0); }
when (io.w.addr === PCR_CAUSE) { reg_cause <== io.w.data(4,0); } when (io.w.addr === PCR_CAUSE) { reg_cause <== io.w.data(4,0); }
when (io.w.addr === PCR_LOG) { reg_log_control <== io.w.data(0).toBool; } when (io.w.addr === PCR_FROMHOST) { reg_fromhost <== io.w.data(31,0); }
when (io.w.addr === PCR_FROMHOST) { reg_fromhost <== io.w.data(w-1,0); }
when (io.w.addr === PCR_K0) { reg_k0 <== io.w.data; } when (io.w.addr === PCR_K0) { reg_k0 <== io.w.data; }
when (io.w.addr === PCR_K1) { reg_k1 <== io.w.data; } when (io.w.addr === PCR_K1) { reg_k1 <== io.w.data; }
when (io.w.addr === PCR_PTBR) { reg_ptbr <== Cat(io.w.data(PADDR_BITS-1, PGIDX_BITS), Bits(0, PGIDX_BITS)).toUFix; } when (io.w.addr === PCR_PTBR) { reg_ptbr <== Cat(io.w.data(PADDR_BITS-1, PGIDX_BITS), Bits(0, PGIDX_BITS)).toUFix; }
} }
when (!io.r.en) { rdata <== Bits(0,2*w); } when (!io.r.en) { rdata <== Bits(0,64); }
switch (io.r.addr) { switch (io.r.addr) {
is (PCR_STATUS) { rdata <== Cat(Bits(0,w+15), reg_status_vm, reg_status_im, reg_status); } is (PCR_STATUS) { rdata <== Cat(Bits(0,47), reg_status_vm, reg_status_im, reg_status); }
is (PCR_EPC) { rdata <== Cat(Fill(2*w-VADDR_BITS, reg_epc(VADDR_BITS-1)), reg_epc); } is (PCR_EPC) { rdata <== Cat(Fill(64-VADDR_BITS, reg_epc(VADDR_BITS-1)), reg_epc); }
is (PCR_BADVADDR) { rdata <== Cat(Fill(2*w-VADDR_BITS, reg_badvaddr(VADDR_BITS-1)), reg_badvaddr); } is (PCR_BADVADDR) { rdata <== Cat(Fill(64-VADDR_BITS, reg_badvaddr(VADDR_BITS-1)), reg_badvaddr); }
is (PCR_EVEC) { rdata <== Cat(Fill(2*w-VADDR_BITS, reg_ebase(VADDR_BITS-1)), reg_ebase); } is (PCR_EVEC) { rdata <== Cat(Fill(64-VADDR_BITS, reg_ebase(VADDR_BITS-1)), reg_ebase); }
is (PCR_COUNT) { rdata <== Cat(Fill(w, reg_count(w-1)), reg_count); } is (PCR_COUNT) { rdata <== Cat(Fill(32, reg_count(31)), reg_count); }
is (PCR_COMPARE) { rdata <== Cat(Fill(w, reg_compare(w-1)), reg_compare); } is (PCR_COMPARE) { rdata <== Cat(Fill(32, reg_compare(31)), reg_compare); }
is (PCR_CAUSE) { rdata <== Cat(Bits(0,w+27), reg_cause); } is (PCR_CAUSE) { rdata <== Cat(Bits(0,59), reg_cause); }
is (PCR_MEMSIZE) { rdata <== Bits(MEMSIZE_PAGES, 64); } is (PCR_MEMSIZE) { rdata <== Bits(MEMSIZE_PAGES,64); }
is (PCR_LOG) { rdata <== Cat(Bits(0,63), reg_log_control); } is (PCR_COREID) { rdata <== Bits(COREID,64); }
is (PCR_FROMHOST) { rdata <== Cat(Fill(w, reg_fromhost(w-1)), reg_fromhost); } is (PCR_NUMCORES) { rdata <== Bits(NUMCORES,64); }
is (PCR_TOHOST) { rdata <== Cat(Fill(w, reg_tohost(w-1)), reg_tohost); } is (PCR_FROMHOST) { rdata <== Cat(Fill(32, reg_fromhost(31)), reg_fromhost); }
is (PCR_TOHOST) { rdata <== Cat(Fill(32, reg_tohost(31)), reg_tohost); }
is (PCR_K0) { rdata <== reg_k0; } is (PCR_K0) { rdata <== reg_k0; }
is (PCR_K1) { rdata <== reg_k1; } is (PCR_K1) { rdata <== reg_k1; }
is (PCR_PTBR) { rdata <== Cat(Bits(0,2*w-PADDR_BITS), reg_ptbr); } is (PCR_PTBR) { rdata <== Cat(Bits(0,64-PADDR_BITS), reg_ptbr); }
otherwise { rdata <== Bits(0,2*w); } otherwise { rdata <== Bits(0,64); }
} }
} }

26
rocket/src/main/scala/dtlb.scala
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@ -56,6 +56,7 @@ class rocketDTLB(entries: Int) extends Component
val tag_ram = Mem(entries, io.ptw.resp_val, r_refill_waddr.toUFix, io.ptw.resp_ppn); val tag_ram = Mem(entries, io.ptw.resp_val, r_refill_waddr.toUFix, io.ptw.resp_ppn);
tag_cam.io.clear := io.cpu.invalidate;
tag_cam.io.tag := lookup_tag; tag_cam.io.tag := lookup_tag;
tag_cam.io.write := io.ptw.resp_val; tag_cam.io.write := io.ptw.resp_val;
tag_cam.io.write_tag := r_refill_tag; tag_cam.io.write_tag := r_refill_tag;
@ -72,15 +73,6 @@ class rocketDTLB(entries: Int) extends Component
val ptw_perm_sr = io.ptw.resp_perm(4); val ptw_perm_sr = io.ptw.resp_perm(4);
val ptw_perm_sw = io.ptw.resp_perm(5); val ptw_perm_sw = io.ptw.resp_perm(5);
// valid bit array
val vb_array = Reg(resetVal = Bits(0, entries));
when (io.cpu.invalidate) {
vb_array <== Bits(0, entries);
}
when (io.ptw.resp_val) {
vb_array <== vb_array.bitSet(r_refill_waddr, Bool(true));
}
// permission bit arrays // permission bit arrays
val ur_array = Reg(resetVal = Bits(0, entries)); // user execute permission val ur_array = Reg(resetVal = Bits(0, entries)); // user execute permission
val uw_array = Reg(resetVal = Bits(0, entries)); // user execute permission val uw_array = Reg(resetVal = Bits(0, entries)); // user execute permission
@ -103,15 +95,15 @@ class rocketDTLB(entries: Int) extends Component
} }
// high if there are any unused (invalid) entries in the TLB // high if there are any unused (invalid) entries in the TLB
val invalid_entry = ~vb_array.toUFix.orR(); val invalid_entry = (tag_cam.io.valid_bits != ~Bits(0,entries));
val ie_enc = new priorityEncoder(entries); val ie_enc = new priorityEncoder(entries);
ie_enc.io.in := vb_array.toUFix; ie_enc.io.in := ~tag_cam.io.valid_bits.toUFix;
val ie_addr = ie_enc.io.out; val ie_addr = ie_enc.io.out;
val repl_waddr = Mux(invalid_entry, ie_addr, repl_count).toUFix; val repl_waddr = Mux(invalid_entry, ie_addr, repl_count).toUFix;
val tag_hit = tag_cam.io.hit && vb_array(tag_hit_addr).toBool; val tag_hit = io.cpu.req_val && tag_cam.io.hit;
val lookup_miss = (state === s_ready) && status_vm && io.cpu.req_val && !tag_hit; val lookup_miss = (state === s_ready) && status_vm && !tag_hit;
when (lookup_miss) { when (lookup_miss) {
r_refill_tag <== lookup_tag; r_refill_tag <== lookup_tag;
@ -123,13 +115,13 @@ class rocketDTLB(entries: Int) extends Component
io.cpu.xcpt_ld := io.cpu.xcpt_ld :=
status_vm && tag_hit && req_load && status_vm && tag_hit && req_load &&
((status_mode && !sw_array(tag_hit_addr).toBool) || !((status_mode && sw_array(tag_hit_addr).toBool) ||
(!status_mode && !uw_array(tag_hit_addr).toBool)); (!status_mode && uw_array(tag_hit_addr).toBool));
io.cpu.xcpt_st := io.cpu.xcpt_st :=
status_vm && tag_hit && req_store && status_vm && tag_hit && req_store &&
((status_mode && !sr_array(tag_hit_addr).toBool) || !((status_mode && sr_array(tag_hit_addr).toBool) ||
(!status_mode && !ur_array(tag_hit_addr).toBool)); (!status_mode && ur_array(tag_hit_addr).toBool));
io.cpu.req_rdy := (state === s_ready); io.cpu.req_rdy := (state === s_ready);
io.cpu.resp_miss := lookup_miss; io.cpu.resp_miss := lookup_miss;

47
rocket/src/main/scala/itlb.scala
View File

@ -6,10 +6,12 @@ import Node._;
import Constants._; import Constants._;
import scala.math._; import scala.math._;
class ioCAM(addr_bits: Int, tag_bits: Int) extends Bundle { class ioCAM(entries: Int, addr_bits: Int, tag_bits: Int) extends Bundle {
val clear = Bool('input);
val tag = Bits(tag_bits, 'input); val tag = Bits(tag_bits, 'input);
val hit = Bool('output); val hit = Bool('output);
val hit_addr = UFix(addr_bits, 'output); val hit_addr = UFix(addr_bits, 'output);
val valid_bits = Bits(entries, 'output);
val write = Bool('input); val write = Bool('input);
val write_tag = Bits(tag_bits, 'input); val write_tag = Bits(tag_bits, 'input);
@ -17,14 +19,22 @@ class ioCAM(addr_bits: Int, tag_bits: Int) extends Bundle {
} }
class rocketCAM(entries: Int, addr_bits: Int, tag_bits: Int) extends Component { class rocketCAM(entries: Int, addr_bits: Int, tag_bits: Int) extends Component {
val io = new ioCAM(addr_bits, tag_bits); val io = new ioCAM(entries, addr_bits, tag_bits);
val cam_tags = Mem(entries, io.write, io.write_addr, io.write_tag); val cam_tags = Mem(entries, io.write, io.write_addr, io.write_tag);
val l_hit = Wire() { Bool() }; val l_hit = Wire() { Bool() };
val l_hit_addr = Wire() { UFix() }; val l_hit_addr = Wire() { UFix() };
val vb_array = Reg(resetVal = Bits(0, entries));
when (io.clear) {
vb_array <== Bits(0, entries);
}
when (io.write) {
vb_array <== vb_array.bitSet(io.write_addr, Bool(true));
}
for (i <- 0 to entries-1) { for (i <- 0 to entries-1) {
when (cam_tags(UFix(i)) === io.tag) { when (vb_array(UFix(i)).toBool && (cam_tags(UFix(i)) === io.tag)) {
l_hit <== Bool(true); l_hit <== Bool(true);
l_hit_addr <== UFix(i,addr_bits); l_hit_addr <== UFix(i,addr_bits);
} }
@ -33,6 +43,7 @@ class rocketCAM(entries: Int, addr_bits: Int, tag_bits: Int) extends Component {
l_hit <== Bool(false); l_hit <== Bool(false);
l_hit_addr <== UFix(0, addr_bits); l_hit_addr <== UFix(0, addr_bits);
io.valid_bits := vb_array;
io.hit := l_hit; io.hit := l_hit;
io.hit_addr := l_hit_addr; io.hit_addr := l_hit_addr;
} }
@ -94,6 +105,7 @@ class rocketITLB(entries: Int) extends Component
val tag_ram = Mem(entries, io.ptw.resp_val, r_refill_waddr.toUFix, io.ptw.resp_ppn); val tag_ram = Mem(entries, io.ptw.resp_val, r_refill_waddr.toUFix, io.ptw.resp_ppn);
tag_cam.io.clear := io.cpu.invalidate;
tag_cam.io.tag := lookup_tag; tag_cam.io.tag := lookup_tag;
tag_cam.io.write := io.ptw.resp_val; tag_cam.io.write := io.ptw.resp_val;
tag_cam.io.write_tag := r_refill_tag; tag_cam.io.write_tag := r_refill_tag;
@ -108,15 +120,6 @@ class rocketITLB(entries: Int) extends Component
val ptw_perm_ux = io.ptw.resp_perm(0); val ptw_perm_ux = io.ptw.resp_perm(0);
val ptw_perm_sx = io.ptw.resp_perm(3); val ptw_perm_sx = io.ptw.resp_perm(3);
// valid bit array
val vb_array = Reg(resetVal = Bits(0, entries));
when (io.cpu.invalidate) {
vb_array <== Bits(0, entries);
}
when (io.ptw.resp_val) {
vb_array <== vb_array.bitSet(r_refill_waddr, Bool(true));
}
// permission bit arrays // permission bit arrays
val ux_array = Reg(resetVal = Bits(0, entries)); // user execute permission val ux_array = Reg(resetVal = Bits(0, entries)); // user execute permission
val sx_array = Reg(resetVal = Bits(0, entries)); // supervisor execute permission val sx_array = Reg(resetVal = Bits(0, entries)); // supervisor execute permission
@ -132,17 +135,16 @@ class rocketITLB(entries: Int) extends Component
sx_array <== sx_array.bitSet(r_refill_waddr, Bool(false)); sx_array <== sx_array.bitSet(r_refill_waddr, Bool(false));
} }
// high if there are any unused (invalid) entries in the ITLB // high if there are any unused entries in the ITLB
// val invalid_entry = orR(~vb_array); val invalid_entry = (tag_cam.io.valid_bits != ~Bits(0,entries));
val invalid_entry = ~vb_array.toUFix.orR();
val ie_enc = new priorityEncoder(entries); val ie_enc = new priorityEncoder(entries);
ie_enc.io.in := vb_array.toUFix; ie_enc.io.in := ~tag_cam.io.valid_bits.toUFix;
val ie_addr = ie_enc.io.out; val ie_addr = ie_enc.io.out;
val repl_waddr = Mux(invalid_entry, ie_addr, repl_count).toUFix; val repl_waddr = Mux(invalid_entry, ie_addr, repl_count).toUFix;
val tag_hit = tag_cam.io.hit && vb_array(tag_hit_addr).toBool; val tag_hit = io.cpu.req_val && tag_cam.io.hit;
val lookup_miss = (state === s_ready) && status_vm && io.cpu.req_val && !tag_hit; val lookup_miss = (state === s_ready) && status_vm && !tag_hit;
when (lookup_miss) { when (lookup_miss) {
r_refill_tag <== lookup_tag; r_refill_tag <== lookup_tag;
@ -153,10 +155,9 @@ class rocketITLB(entries: Int) extends Component
} }
val itlb_exception = val itlb_exception =
io.cpu.req_val && tag_hit && tag_hit &&
((status_mode && !sx_array(tag_hit_addr).toBool) || !((status_mode && sx_array(tag_hit_addr).toBool) ||
(!status_mode && !ux_array(tag_hit_addr).toBool) || (!status_mode && ux_array(tag_hit_addr).toBool));
(io.cpu.resp_addr >= MEMSIZE));
io.cpu.req_rdy := (state === s_ready); io.cpu.req_rdy := (state === s_ready);
io.cpu.resp_val := Mux(status_vm, tag_hit, io.cpu.req_val); io.cpu.resp_val := Mux(status_vm, tag_hit, io.cpu.req_val);
@ -171,7 +172,7 @@ class rocketITLB(entries: Int) extends Component
// control state machine // control state machine
switch (state) { switch (state) {
is (s_ready) { is (s_ready) {
when (status_vm && io.cpu.req_val && !tag_hit) { when (status_vm && !tag_hit) {
state <== s_request; state <== s_request;
} }
} }

17
rocket/src/main/scala/ptw.scala
View File

@ -27,14 +27,13 @@ class rocketDmemArbiter extends Component
io.cpu.req_rdy := io.mem.req_rdy && !io.ptw.req_val; io.cpu.req_rdy := io.mem.req_rdy && !io.ptw.req_val;
io.cpu.resp_miss := io.mem.resp_miss; // FIXME io.cpu.resp_miss := io.mem.resp_miss; // FIXME
io.cpu.resp_val := io.mem.resp_val && !io.mem.resp_tag(12).toBool; io.cpu.resp_val := io.mem.resp_val && !io.mem.resp_tag(11).toBool;
io.ptw.resp_val := io.mem.resp_val && io.mem.resp_tag(12).toBool; io.ptw.resp_val := io.mem.resp_val && io.mem.resp_tag(11).toBool;
io.ptw.resp_data := io.mem.resp_data; io.ptw.resp_data := io.mem.resp_data;
io.cpu.resp_data := io.mem.resp_data; io.cpu.resp_data := io.mem.resp_data;
// io.cpu.resp_tag := io.mem.resp_tag(11,0); // io.cpu.resp_tag := io.mem.resp_tag(10,0);
io.cpu.resp_tag := io.mem.resp_tag; // to get rid of warning, MSB of tag is ignored in dpath io.cpu.resp_tag := io.mem.resp_tag;
} }
class ioPTW extends Bundle class ioPTW extends Bundle
@ -55,7 +54,7 @@ class rocketPTW extends Component
val r_req_vpn = Reg(resetVal = Bits(0,VPN_BITS)); val r_req_vpn = Reg(resetVal = Bits(0,VPN_BITS));
val r_req_dest = Reg(resetVal = Bool(false)); // 0 = ITLB, 1 = DTLB val r_req_dest = Reg(resetVal = Bool(false)); // 0 = ITLB, 1 = DTLB
val req_addr = Reg(resetVal = UFix(0,PPN_BITS+PGIDX_BITS)); val req_addr = Reg(resetVal = UFix(0,PADDR_BITS));
val r_resp_ppn = Reg(resetVal = Bits(0,PPN_BITS)); val r_resp_ppn = Reg(resetVal = Bits(0,PPN_BITS));
val r_resp_perm = Reg(resetVal = Bits(0,PERM_BITS)); val r_resp_perm = Reg(resetVal = Bits(0,PERM_BITS));
@ -69,17 +68,17 @@ class rocketPTW extends Component
when ((state === s_ready) && req_itlb_val) { when ((state === s_ready) && req_itlb_val) {
r_req_vpn <== io.itlb.req_vpn; r_req_vpn <== io.itlb.req_vpn;
r_req_dest <== Bool(false); r_req_dest <== Bool(false);
req_addr <== Cat(io.ptbr(PADDR_BITS-1,PGIDX_BITS), io.itlb.req_vpn(VPN_BITS-1,VPN_BITS-10)).toUFix; req_addr <== Cat(io.ptbr(PADDR_BITS-1,PGIDX_BITS), io.itlb.req_vpn(VPN_BITS-1,VPN_BITS-10), Bits(0,3)).toUFix;
} }
when ((state === s_ready) && req_dtlb_val) { when ((state === s_ready) && req_dtlb_val) {
r_req_vpn <== io.dtlb.req_vpn; r_req_vpn <== io.dtlb.req_vpn;
r_req_dest <== Bool(true); r_req_dest <== Bool(true);
req_addr <== Cat(io.ptbr(PADDR_BITS-1,PGIDX_BITS), io.dtlb.req_vpn(VPN_BITS-1,VPN_BITS-10)).toUFix; req_addr <== Cat(io.ptbr(PADDR_BITS-1,PGIDX_BITS), io.dtlb.req_vpn(VPN_BITS-1,VPN_BITS-10), Bits(0,3)).toUFix;
} }
when (io.dmem.resp_val) { when (io.dmem.resp_val) {
req_addr <== Cat(io.dmem.resp_data(PADDR_BITS-1, PGIDX_BITS), vpn_idx).toUFix; req_addr <== Cat(io.dmem.resp_data(PADDR_BITS-1, PGIDX_BITS), vpn_idx, Bits(0,3)).toUFix;
r_resp_perm <== io.dmem.resp_data(9,4); r_resp_perm <== io.dmem.resp_data(9,4);
r_resp_ppn <== io.dmem.resp_data(PADDR_BITS-1, PGIDX_BITS); r_resp_ppn <== io.dmem.resp_data(PADDR_BITS-1, PGIDX_BITS);
} }