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Remove irq support.

This commit is contained in:
colin.liang 2023-01-16 20:41:28 +08:00
parent 2b3f3d3f3d
commit ef6fb8848f
6 changed files with 25 additions and 629 deletions
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4
Makefile
View File

@ -12,7 +12,7 @@ IVERILOG = iverilog$(ICARUS_SUFFIX)
VVP = vvp$(ICARUS_SUFFIX)
TEST_OBJS = $(addsuffix .o,$(basename $(wildcard tests/*.S)))
FIRMWARE_OBJS = build/start.o build/irq.o build/print.o build/hello.o build/sieve.o build/multest.o build/stats.o
FIRMWARE_OBJS = build/start.o build/print.o build/hello.o build/sieve.o build/multest.o build/stats.o
GCC_WARNS = -Werror -Wall -Wextra -Wshadow -Wundef -Wpointer-arith -Wcast-qual -Wcast-align -Wwrite-strings
GCC_WARNS += -Wredundant-decls -Wstrict-prototypes -Wmissing-prototypes -pedantic # -Wconversion
TOOLCHAIN_PREFIX = $(RISCV_GNU_TOOLCHAIN_INSTALL_PREFIX)/bin/riscv32-unknown-elf-
@ -25,7 +25,7 @@ test_verilator: build/testbench_verilator build/firmware.hex build/dhry.hex
cd build && ./testbench_verilator firmware.hex
cd build && ./testbench_verilator dhry.hex
firmware: build/testbench_verilator
firmware: build/testbench_verilator build/firmware.hex
cd build && ./testbench_verilator firmware.hex
dhry: build/firmware.hex build/dhry.hex

3
firmware/firmware.h
View File

@ -11,9 +11,6 @@
#include <stdint.h>
#include <stdbool.h>
// irq.c
uint32_t *irq(uint32_t *regs, uint32_t irqs);
// print.c
void print_chr(char ch);
void print_str(const char *p);

140
firmware/irq.c
View File

@ -1,140 +0,0 @@
// This is free and unencumbered software released into the public domain.
//
// Anyone is free to copy, modify, publish, use, compile, sell, or
// distribute this software, either in source code form or as a compiled
// binary, for any purpose, commercial or non-commercial, and by any
// means.
#include "firmware.h"
uint32_t *irq(uint32_t *regs, uint32_t irqs)
{
static unsigned int ext_irq_4_count = 0;
static unsigned int ext_irq_5_count = 0;
static unsigned int timer_irq_count = 0;
// checking compressed isa q0 reg handling
if ((irqs & 6) != 0) {
uint32_t pc = (regs[0] & 1) ? regs[0] - 3 : regs[0] - 4;
uint32_t instr = *(uint16_t*)pc;
if ((instr & 3) == 3)
instr = instr | (*(uint16_t*)(pc + 2)) << 16;
if (((instr & 3) != 3) != (regs[0] & 1)) {
print_str("Mismatch between q0 LSB and decoded instruction word! q0=0x");
print_hex(regs[0], 8);
print_str(", instr=0x");
if ((instr & 3) == 3)
print_hex(instr, 8);
else
print_hex(instr, 4);
print_str("\n");
__asm__ volatile ("ebreak");
}
}
if ((irqs & (1<<4)) != 0) {
ext_irq_4_count++;
// print_str("[EXT-IRQ-4]");
}
if ((irqs & (1<<5)) != 0) {
ext_irq_5_count++;
// print_str("[EXT-IRQ-5]");
}
if ((irqs & 1) != 0) {
timer_irq_count++;
// print_str("[TIMER-IRQ]");
}
if ((irqs & 6) != 0)
{
uint32_t pc = (regs[0] & 1) ? regs[0] - 3 : regs[0] - 4;
uint32_t instr = *(uint16_t*)pc;
if ((instr & 3) == 3)
instr = instr | (*(uint16_t*)(pc + 2)) << 16;
print_str("\n");
print_str("------------------------------------------------------------\n");
if ((irqs & 2) != 0) {
if (instr == 0x00100073 || instr == 0x9002) {
print_str("EBREAK instruction at 0x");
print_hex(pc, 8);
print_str("\n");
} else {
print_str("Illegal Instruction at 0x");
print_hex(pc, 8);
print_str(": 0x");
print_hex(instr, ((instr & 3) == 3) ? 8 : 4);
print_str("\n");
}
}
if ((irqs & 4) != 0) {
print_str("Bus error in Instruction at 0x");
print_hex(pc, 8);
print_str(": 0x");
print_hex(instr, ((instr & 3) == 3) ? 8 : 4);
print_str("\n");
}
for (int i = 0; i < 8; i++)
for (int k = 0; k < 4; k++)
{
int r = i + k*8;
if (r == 0) {
print_str("pc ");
} else
if (r < 10) {
print_chr('x');
print_chr('0' + r);
print_chr(' ');
print_chr(' ');
} else
if (r < 20) {
print_chr('x');
print_chr('1');
print_chr('0' + r - 10);
print_chr(' ');
} else
if (r < 30) {
print_chr('x');
print_chr('2');
print_chr('0' + r - 20);
print_chr(' ');
} else {
print_chr('x');
print_chr('3');
print_chr('0' + r - 30);
print_chr(' ');
}
print_hex(regs[r], 8);
print_str(k == 3 ? "\n" : " ");
}
print_str("------------------------------------------------------------\n");
print_str("Number of fast external IRQs counted: ");
print_dec(ext_irq_4_count);
print_str("\n");
print_str("Number of slow external IRQs counted: ");
print_dec(ext_irq_5_count);
print_str("\n");
print_str("Number of timer IRQs counted: ");
print_dec(timer_irq_count);
print_str("\n");
__asm__ volatile ("ebreak");
}
return regs;
}

309
firmware/start.S
View File

@ -5,26 +5,14 @@
// binary, for any purpose, commercial or non-commercial, and by any
// means.
#define ENABLE_QREGS
#define ENABLE_HELLO
#define ENABLE_RVTST
#define ENABLE_SIEVE
#define ENABLE_MULTST
#define ENABLE_STATS
#ifndef ENABLE_QREGS
# undef ENABLE_RVTST
#endif
// Only save registers in IRQ wrapper that are to be saved by the caller in
// the RISC-V ABI, with the excpetion of the stack pointer. The IRQ handler
// will save the rest if necessary. I.e. skip x3, x4, x8, x9, and x18-x27.
#undef ENABLE_FASTIRQ
#include "custom_ops.S"
.section .text
.global irq
.global hello
.global sieve
.global multest
@ -39,305 +27,8 @@
.global stats
reset_vec:
// no more than 16 bytes here !
picorv32_waitirq_insn(zero)
picorv32_maskirq_insn(zero, zero)
j start
/* Interrupt handler
**********************************/
.balign 16
irq_vec:
/* save registers */
#ifdef ENABLE_QREGS
picorv32_setq_insn(q2, x1)
picorv32_setq_insn(q3, x2)
lui x1, %hi(irq_regs)
addi x1, x1, %lo(irq_regs)
picorv32_getq_insn(x2, q0)
sw x2, 0*4(x1)
picorv32_getq_insn(x2, q2)
sw x2, 1*4(x1)
picorv32_getq_insn(x2, q3)
sw x2, 2*4(x1)
#ifdef ENABLE_FASTIRQ
sw x5, 5*4(x1)
sw x6, 6*4(x1)
sw x7, 7*4(x1)
sw x10, 10*4(x1)
sw x11, 11*4(x1)
sw x12, 12*4(x1)
sw x13, 13*4(x1)
sw x14, 14*4(x1)
sw x15, 15*4(x1)
sw x16, 16*4(x1)
sw x17, 17*4(x1)
sw x28, 28*4(x1)
sw x29, 29*4(x1)
sw x30, 30*4(x1)
sw x31, 31*4(x1)
#else
sw x3, 3*4(x1)
sw x4, 4*4(x1)
sw x5, 5*4(x1)
sw x6, 6*4(x1)
sw x7, 7*4(x1)
sw x8, 8*4(x1)
sw x9, 9*4(x1)
sw x10, 10*4(x1)
sw x11, 11*4(x1)
sw x12, 12*4(x1)
sw x13, 13*4(x1)
sw x14, 14*4(x1)
sw x15, 15*4(x1)
sw x16, 16*4(x1)
sw x17, 17*4(x1)
sw x18, 18*4(x1)
sw x19, 19*4(x1)
sw x20, 20*4(x1)
sw x21, 21*4(x1)
sw x22, 22*4(x1)
sw x23, 23*4(x1)
sw x24, 24*4(x1)
sw x25, 25*4(x1)
sw x26, 26*4(x1)
sw x27, 27*4(x1)
sw x28, 28*4(x1)
sw x29, 29*4(x1)
sw x30, 30*4(x1)
sw x31, 31*4(x1)
#endif
#else // ENABLE_QREGS
#ifdef ENABLE_FASTIRQ
sw gp, 0*4+0x200(zero)
sw x1, 1*4+0x200(zero)
sw x2, 2*4+0x200(zero)
sw x5, 5*4+0x200(zero)
sw x6, 6*4+0x200(zero)
sw x7, 7*4+0x200(zero)
sw x10, 10*4+0x200(zero)
sw x11, 11*4+0x200(zero)
sw x12, 12*4+0x200(zero)
sw x13, 13*4+0x200(zero)
sw x14, 14*4+0x200(zero)
sw x15, 15*4+0x200(zero)
sw x16, 16*4+0x200(zero)
sw x17, 17*4+0x200(zero)
sw x28, 28*4+0x200(zero)
sw x29, 29*4+0x200(zero)
sw x30, 30*4+0x200(zero)
sw x31, 31*4+0x200(zero)
#else
sw gp, 0*4+0x200(zero)
sw x1, 1*4+0x200(zero)
sw x2, 2*4+0x200(zero)
sw x3, 3*4+0x200(zero)
sw x4, 4*4+0x200(zero)
sw x5, 5*4+0x200(zero)
sw x6, 6*4+0x200(zero)
sw x7, 7*4+0x200(zero)
sw x8, 8*4+0x200(zero)
sw x9, 9*4+0x200(zero)
sw x10, 10*4+0x200(zero)
sw x11, 11*4+0x200(zero)
sw x12, 12*4+0x200(zero)
sw x13, 13*4+0x200(zero)
sw x14, 14*4+0x200(zero)
sw x15, 15*4+0x200(zero)
sw x16, 16*4+0x200(zero)
sw x17, 17*4+0x200(zero)
sw x18, 18*4+0x200(zero)
sw x19, 19*4+0x200(zero)
sw x20, 20*4+0x200(zero)
sw x21, 21*4+0x200(zero)
sw x22, 22*4+0x200(zero)
sw x23, 23*4+0x200(zero)
sw x24, 24*4+0x200(zero)
sw x25, 25*4+0x200(zero)
sw x26, 26*4+0x200(zero)
sw x27, 27*4+0x200(zero)
sw x28, 28*4+0x200(zero)
sw x29, 29*4+0x200(zero)
sw x30, 30*4+0x200(zero)
sw x31, 31*4+0x200(zero)
#endif
#endif // ENABLE_QREGS
/* call interrupt handler C function */
lui sp, %hi(irq_stack)
addi sp, sp, %lo(irq_stack)
// arg0 = address of regs
lui a0, %hi(irq_regs)
addi a0, a0, %lo(irq_regs)
// arg1 = interrupt type
#ifdef ENABLE_QREGS
picorv32_getq_insn(a1, q1)
#else
addi a1, tp, 0
#endif
// call to C function
jal ra, irq
/* restore registers */
#ifdef ENABLE_QREGS
// new irq_regs address returned from C code in a0
addi x1, a0, 0
lw x2, 0*4(x1)
picorv32_setq_insn(q0, x2)
lw x2, 1*4(x1)
picorv32_setq_insn(q1, x2)
lw x2, 2*4(x1)
picorv32_setq_insn(q2, x2)
#ifdef ENABLE_FASTIRQ
lw x5, 5*4(x1)
lw x6, 6*4(x1)
lw x7, 7*4(x1)
lw x10, 10*4(x1)
lw x11, 11*4(x1)
lw x12, 12*4(x1)
lw x13, 13*4(x1)
lw x14, 14*4(x1)
lw x15, 15*4(x1)
lw x16, 16*4(x1)
lw x17, 17*4(x1)
lw x28, 28*4(x1)
lw x29, 29*4(x1)
lw x30, 30*4(x1)
lw x31, 31*4(x1)
#else
lw x3, 3*4(x1)
lw x4, 4*4(x1)
lw x5, 5*4(x1)
lw x6, 6*4(x1)
lw x7, 7*4(x1)
lw x8, 8*4(x1)
lw x9, 9*4(x1)
lw x10, 10*4(x1)
lw x11, 11*4(x1)
lw x12, 12*4(x1)
lw x13, 13*4(x1)
lw x14, 14*4(x1)
lw x15, 15*4(x1)
lw x16, 16*4(x1)
lw x17, 17*4(x1)
lw x18, 18*4(x1)
lw x19, 19*4(x1)
lw x20, 20*4(x1)
lw x21, 21*4(x1)
lw x22, 22*4(x1)
lw x23, 23*4(x1)
lw x24, 24*4(x1)
lw x25, 25*4(x1)
lw x26, 26*4(x1)
lw x27, 27*4(x1)
lw x28, 28*4(x1)
lw x29, 29*4(x1)
lw x30, 30*4(x1)
lw x31, 31*4(x1)
#endif
picorv32_getq_insn(x1, q1)
picorv32_getq_insn(x2, q2)
#else // ENABLE_QREGS
// new irq_regs address returned from C code in a0
addi a1, zero, 0x200
beq a0, a1, 1f
ebreak
1:
#ifdef ENABLE_FASTIRQ
lw gp, 0*4+0x200(zero)
lw x1, 1*4+0x200(zero)
lw x2, 2*4+0x200(zero)
lw x5, 5*4+0x200(zero)
lw x6, 6*4+0x200(zero)
lw x7, 7*4+0x200(zero)
lw x10, 10*4+0x200(zero)
lw x11, 11*4+0x200(zero)
lw x12, 12*4+0x200(zero)
lw x13, 13*4+0x200(zero)
lw x14, 14*4+0x200(zero)
lw x15, 15*4+0x200(zero)
lw x16, 16*4+0x200(zero)
lw x17, 17*4+0x200(zero)
lw x28, 28*4+0x200(zero)
lw x29, 29*4+0x200(zero)
lw x30, 30*4+0x200(zero)
lw x31, 31*4+0x200(zero)
#else
lw gp, 0*4+0x200(zero)
lw x1, 1*4+0x200(zero)
lw x2, 2*4+0x200(zero)
// do not restore x3 (gp)
lw x4, 4*4+0x200(zero)
lw x5, 5*4+0x200(zero)
lw x6, 6*4+0x200(zero)
lw x7, 7*4+0x200(zero)
lw x8, 8*4+0x200(zero)
lw x9, 9*4+0x200(zero)
lw x10, 10*4+0x200(zero)
lw x11, 11*4+0x200(zero)
lw x12, 12*4+0x200(zero)
lw x13, 13*4+0x200(zero)
lw x14, 14*4+0x200(zero)
lw x15, 15*4+0x200(zero)
lw x16, 16*4+0x200(zero)
lw x17, 17*4+0x200(zero)
lw x18, 18*4+0x200(zero)
lw x19, 19*4+0x200(zero)
lw x20, 20*4+0x200(zero)
lw x21, 21*4+0x200(zero)
lw x22, 22*4+0x200(zero)
lw x23, 23*4+0x200(zero)
lw x24, 24*4+0x200(zero)
lw x25, 25*4+0x200(zero)
lw x26, 26*4+0x200(zero)
lw x27, 27*4+0x200(zero)
lw x28, 28*4+0x200(zero)
lw x29, 29*4+0x200(zero)
lw x30, 30*4+0x200(zero)
lw x31, 31*4+0x200(zero)
#endif
#endif // ENABLE_QREGS
picorv32_retirq_insn()
.balign 0x200
irq_regs:
// registers are saved to this memory region during interrupt handling
// the program counter is saved as register 0
.fill 32,4
// stack for the interrupt handler
.fill 128,4
irq_stack:
/* Main program
**********************************/

191
picorv32.v
View File

@ -24,6 +24,7 @@
`timescale 1 ns / 1 ps
// `default_nettype none
// `define DEBUG
`ifdef DEBUG
`define debug(debug_command) debug_command
@ -40,10 +41,7 @@
module picorv32 #(
parameter [0:0] ENABLE_TRACE = 0,
parameter [31:0] MASKED_IRQ = 32'h0000_0000,
parameter [31:0] LATCHED_IRQ = 32'hffff_ffff,
parameter [31:0] PROGADDR_RESET = 32'h0000_0000,
parameter [31:0] PROGADDR_IRQ = 32'h0000_0010,
parameter [31:0] STACKADDR = 32'hffff_ffff
) (
input clk,
@ -76,10 +74,6 @@ module picorv32 #(
input pcpi_wait,
input pcpi_ready,
// IRQ Interface
input [31:0] irq,
output reg [31:0] eoi,
// Trace Interface
output reg trace_valid,
output reg [35:0] trace_data,
@ -90,16 +84,11 @@ module picorv32 #(
output reg [31:0] dbg_insn_addr,
output reg [63:0] dbg_ascii_instr
);
localparam integer irq_timer = 0;
localparam integer irq_ebreak = 1;
localparam integer irq_buserror = 2;
localparam integer irqregs_offset = 32;
localparam integer regfile_size = 32 + 4;
localparam integer regindex_bits = 5 + 1;
localparam integer regfile_size = 32;
localparam integer regindex_bits = 5;
localparam [35:0] TRACE_BRANCH = {4'b0001, 32'b0};
localparam [35:0] TRACE_ADDR = {4'b0010, 32'b0};
localparam [35:0] TRACE_IRQ = {4'b1000, 32'b0};
reg [63:0] count_cycle, count_instr;
reg [31:0] reg_pc, reg_next_pc, reg_op1, reg_op2, reg_out;
@ -120,12 +109,6 @@ module picorv32 #(
wire [31:0] next_pc;
reg irq_delay;
reg irq_active;
reg [31:0] irq_mask;
reg [31:0] irq_pending;
reg [31:0] timer;
task empty_statement;
// This task is used by the `assert directive in non-formal mode to
// avoid empty statement (which are unsupported by plain Verilog syntax).
@ -362,7 +345,6 @@ module picorv32 #(
reg instr_add, instr_sub, instr_sll, instr_slt, instr_sltu;
reg instr_xor, instr_srl, instr_sra, instr_or, instr_and;
reg instr_rdcycle, instr_rdcycleh, instr_rdinstr, instr_rdinstrh, instr_ecall_ebreak;
reg instr_getq, instr_setq, instr_retirq, instr_maskirq, instr_waitirq, instr_timer;
wire instr_trap;
reg [regindex_bits-1:0] decoded_rd, decoded_rs1, decoded_rs2;
@ -392,8 +374,7 @@ module picorv32 #(
instr_lb, instr_lh, instr_lw, instr_lbu, instr_lhu, instr_sb, instr_sh, instr_sw,
instr_addi, instr_slti, instr_sltiu, instr_xori, instr_ori, instr_andi, instr_slli, instr_srli, instr_srai,
instr_add, instr_sub, instr_sll, instr_slt, instr_sltu, instr_xor, instr_srl, instr_sra, instr_or, instr_and,
instr_rdcycle, instr_rdcycleh, instr_rdinstr, instr_rdinstrh,
instr_getq, instr_setq, instr_retirq, instr_maskirq, instr_waitirq, instr_timer};
instr_rdcycle, instr_rdcycleh, instr_rdinstr, instr_rdinstrh};
wire is_rdcycle_rdcycleh_rdinstr_rdinstrh;
assign is_rdcycle_rdcycleh_rdinstr_rdinstrh = |{instr_rdcycle, instr_rdcycleh, instr_rdinstr, instr_rdinstrh};
@ -461,12 +442,6 @@ module picorv32 #(
if (instr_rdinstr) new_ascii_instr = "rdinstr";
if (instr_rdinstrh) new_ascii_instr = "rdinstrh";
if (instr_getq) new_ascii_instr = "getq";
if (instr_setq) new_ascii_instr = "setq";
if (instr_retirq) new_ascii_instr = "retirq";
if (instr_maskirq) new_ascii_instr = "maskirq";
if (instr_waitirq) new_ascii_instr = "waitirq";
if (instr_timer) new_ascii_instr = "timer";
end
reg [63:0] q_ascii_instr;
@ -554,8 +529,6 @@ module picorv32 #(
instr_auipc <= mem_rdata_latched[6:0] == 7'b0010111;
instr_jal <= mem_rdata_latched[6:0] == 7'b1101111;
instr_jalr <= mem_rdata_latched[6:0] == 7'b1100111 && mem_rdata_latched[14:12] == 3'b000;
instr_retirq <= mem_rdata_latched[6:0] == 7'b0001011 && mem_rdata_latched[31:25] == 7'b0000010;
instr_waitirq <= mem_rdata_latched[6:0] == 7'b0001011 && mem_rdata_latched[31:25] == 7'b0000100;
is_beq_bne_blt_bge_bltu_bgeu <= mem_rdata_latched[6:0] == 7'b1100011;
is_lb_lh_lw_lbu_lhu <= mem_rdata_latched[6:0] == 7'b0000011;
@ -570,12 +543,6 @@ module picorv32 #(
decoded_rd <= mem_rdata_latched[11:7];
decoded_rs1 <= mem_rdata_latched[19:15];
decoded_rs2 <= mem_rdata_latched[24:20];
if (mem_rdata_latched[6:0] == 7'b0001011 && mem_rdata_latched[31:25] == 7'b0000000)
decoded_rs1[regindex_bits-1] <= 1; // instr_getq
if (mem_rdata_latched[6:0] == 7'b0001011 && mem_rdata_latched[31:25] == 7'b0000010)
decoded_rs1 <= irqregs_offset; // instr_retirq
end
if (decoder_trigger && !decoder_pseudo_trigger) begin
@ -629,11 +596,6 @@ module picorv32 #(
instr_ecall_ebreak <= (mem_rdata_q[6:0] == 7'b1110011 && !mem_rdata_q[31:21] && !mem_rdata_q[19:7]);
instr_getq <= mem_rdata_q[6:0] == 7'b0001011 && mem_rdata_q[31:25] == 7'b0000000;
instr_setq <= mem_rdata_q[6:0] == 7'b0001011 && mem_rdata_q[31:25] == 7'b0000001;
instr_maskirq <= mem_rdata_q[6:0] == 7'b0001011 && mem_rdata_q[31:25] == 7'b0000011;
instr_timer <= mem_rdata_q[6:0] == 7'b0001011 && mem_rdata_q[31:25] == 7'b0000101;
is_slli_srli_srai <= is_alu_reg_imm && |{
mem_rdata_q[14:12] == 3'b001 && mem_rdata_q[31:25] == 7'b0000000,
mem_rdata_q[14:12] == 3'b101 && mem_rdata_q[31:25] == 7'b0000000,
@ -717,7 +679,6 @@ module picorv32 #(
localparam cpu_state_ldmem = 8'b00000001;
reg [7:0] cpu_state;
reg [1:0] irq_state;
always @* begin
dbg_ascii_state = "";
@ -750,9 +711,6 @@ module picorv32 #(
reg [3:0] pcpi_timeout_counter;
reg pcpi_timeout;
reg [31:0] next_irq_pending;
reg do_waitirq;
reg [31:0] alu_out, alu_out_q;
reg alu_out_0, alu_out_0_q;
@ -815,14 +773,6 @@ module picorv32 #(
cpuregs_wrdata = latched_stalu ? alu_out_q : reg_out;
cpuregs_write = 1;
end
irq_state[0]: begin
cpuregs_wrdata = reg_next_pc;
cpuregs_write = 1;
end
irq_state[1]: begin
cpuregs_wrdata = irq_pending & ~irq_mask;
cpuregs_write = 1;
end
endcase
end
end
@ -851,7 +801,7 @@ module picorv32 #(
cpuregs_rs2 = decoded_rs2 ? cpuregs_rdata2 : 0;
end
assign launch_next_insn = cpu_state == cpu_state_fetch && decoder_trigger && (irq_delay || irq_active || !(irq_pending & ~irq_mask));
assign launch_next_insn = cpu_state == cpu_state_fetch && decoder_trigger;
always @(posedge clk) begin
trap <= 0;
@ -876,17 +826,11 @@ module picorv32 #(
end else pcpi_timeout_counter <= ~0;
pcpi_timeout <= !pcpi_timeout_counter;
count_cycle <= resetn ? count_cycle + 1 : 0;
next_irq_pending = irq_pending & LATCHED_IRQ;
if (timer) begin
timer <= timer - 1;
end
decoder_trigger <= mem_do_rinst && mem_done;
decoder_trigger_q <= decoder_trigger;
decoder_pseudo_trigger <= 0;
decoder_pseudo_trigger_q <= decoder_pseudo_trigger;
do_waitirq <= 0;
trace_valid <= 0;
@ -905,13 +849,6 @@ module picorv32 #(
latched_is_lb <= 0;
pcpi_valid <= 0;
pcpi_timeout <= 0;
irq_active <= 0;
irq_delay <= 0;
irq_mask <= ~0;
next_irq_pending = 0;
irq_state <= 0;
eoi <= 0;
timer <= 0;
if (~STACKADDR) begin
latched_store <= 1;
latched_rd <= 2;
@ -925,7 +862,7 @@ module picorv32 #(
end
cpu_state_fetch: begin
mem_do_rinst <= !decoder_trigger && !do_waitirq;
mem_do_rinst <= !decoder_trigger;
mem_wordsize <= 0;
current_pc = reg_next_pc;
@ -941,23 +878,13 @@ module picorv32 #(
`debug($display("ST_RD: %2d 0x%08x", latched_rd, latched_stalu ? alu_out_q : reg_out
);)
end
irq_state[0]: begin
current_pc = PROGADDR_IRQ;
irq_active <= 1;
mem_do_rinst <= 1;
end
irq_state[1]: begin
eoi <= irq_pending & ~irq_mask;
next_irq_pending = next_irq_pending & irq_mask;
end
endcase
if (ENABLE_TRACE && latched_trace) begin
latched_trace <= 0;
trace_valid <= 1;
if (latched_branch)
trace_data <= (irq_active ? TRACE_IRQ : 0) | TRACE_BRANCH | (current_pc & 32'hfffffffe);
else trace_data <= (irq_active ? TRACE_IRQ : 0) | (latched_stalu ? alu_out_q : reg_out);
if (latched_branch) trace_data <= TRACE_BRANCH | (current_pc & 32'hfffffffe);
else trace_data <= latched_stalu ? alu_out_q : reg_out;
end
reg_pc <= current_pc;
@ -971,19 +898,8 @@ module picorv32 #(
latched_is_lb <= 0;
latched_rd <= decoded_rd;
if (((decoder_trigger && !irq_active && !irq_delay && |(irq_pending & ~irq_mask)) || irq_state)) begin
irq_state <= irq_state == 2'b00 ? 2'b01 : irq_state == 2'b01 ? 2'b10 : 2'b00;
latched_rd <= irqregs_offset | irq_state[0];
end else if ((decoder_trigger || do_waitirq) && instr_waitirq) begin
if (irq_pending) begin
latched_store <= 1;
reg_out <= irq_pending;
reg_next_pc <= current_pc + 4;
mem_do_rinst <= 1;
end else do_waitirq <= 1;
end else if (decoder_trigger) begin
if (decoder_trigger) begin
`debug($display("-- %-0t", $time);)
irq_delay <= irq_active;
reg_next_pc <= current_pc + 4;
if (ENABLE_TRACE) latched_trace <= 1;
count_instr <= count_instr + 1;
@ -993,7 +909,7 @@ module picorv32 #(
latched_branch <= 1;
end else begin
mem_do_rinst <= 0;
mem_do_prefetch <= !instr_jalr && !instr_retirq;
mem_do_prefetch <= !instr_jalr;
cpu_state <= cpu_state_ld_rs1;
end
end
@ -1025,10 +941,7 @@ module picorv32 #(
end else if (pcpi_timeout || instr_ecall_ebreak) begin
pcpi_valid <= 0;
`debug($display("EBREAK OR UNSUPPORTED INSN AT 0x%08x", reg_pc);)
if (!irq_mask[irq_ebreak] && !irq_active) begin
next_irq_pending[irq_ebreak] = 1;
cpu_state <= cpu_state_fetch;
end else cpu_state <= cpu_state_trap;
cpu_state <= cpu_state_trap;
end
end
is_rdcycle_rdcycleh_rdinstr_rdinstrh: begin
@ -1048,52 +961,6 @@ module picorv32 #(
mem_do_rinst <= mem_do_prefetch;
cpu_state <= cpu_state_exec;
end
instr_getq: begin
`debug($display("LD_RS1: %2d 0x%08x", decoded_rs1, cpuregs_rs1);)
reg_out <= cpuregs_rs1;
dbg_rs1val <= cpuregs_rs1;
dbg_rs1val_valid <= 1;
latched_store <= 1;
cpu_state <= cpu_state_fetch;
end
instr_setq: begin
`debug($display("LD_RS1: %2d 0x%08x", decoded_rs1, cpuregs_rs1);)
reg_out <= cpuregs_rs1;
dbg_rs1val <= cpuregs_rs1;
dbg_rs1val_valid <= 1;
latched_rd <= latched_rd | irqregs_offset;
latched_store <= 1;
cpu_state <= cpu_state_fetch;
end
instr_retirq: begin
eoi <= 0;
irq_active <= 0;
latched_branch <= 1;
latched_store <= 1;
`debug($display("LD_RS1: %2d 0x%08x", decoded_rs1, cpuregs_rs1);)
reg_out <= cpuregs_rs1 & 32'hfffffffe;
dbg_rs1val <= cpuregs_rs1;
dbg_rs1val_valid <= 1;
cpu_state <= cpu_state_fetch;
end
instr_maskirq: begin
latched_store <= 1;
reg_out <= irq_mask;
`debug($display("LD_RS1: %2d 0x%08x", decoded_rs1, cpuregs_rs1);)
irq_mask <= cpuregs_rs1 | MASKED_IRQ;
dbg_rs1val <= cpuregs_rs1;
dbg_rs1val_valid <= 1;
cpu_state <= cpu_state_fetch;
end
instr_timer: begin
latched_store <= 1;
reg_out <= timer;
`debug($display("LD_RS1: %2d 0x%08x", decoded_rs1, cpuregs_rs1);)
timer <= cpuregs_rs1;
dbg_rs1val <= cpuregs_rs1;
dbg_rs1val_valid <= 1;
cpu_state <= cpu_state_fetch;
end
is_lb_lh_lw_lbu_lhu && !instr_trap: begin
`debug($display("LD_RS1: %2d 0x%08x", decoded_rs1, cpuregs_rs1);)
reg_op1 <= cpuregs_rs1;
@ -1167,10 +1034,7 @@ module picorv32 #(
end else if (pcpi_timeout || instr_ecall_ebreak) begin
pcpi_valid <= 0;
`debug($display("EBREAK OR UNSUPPORTED INSN AT 0x%08x", reg_pc);)
if (!irq_mask[irq_ebreak] && !irq_active) begin
next_irq_pending[irq_ebreak] = 1;
cpu_state <= cpu_state_fetch;
end else cpu_state <= cpu_state_trap;
cpu_state <= cpu_state_trap;
end
end
is_sb_sh_sw: begin
@ -1205,7 +1069,6 @@ module picorv32 #(
cpu_state <= cpu_state_fetch;
end
end
cpu_state_shift: begin
latched_store <= 1;
if (reg_sh == 0) begin
@ -1243,7 +1106,7 @@ module picorv32 #(
endcase
if (ENABLE_TRACE) begin
trace_valid <= 1;
trace_data <= (irq_active ? TRACE_IRQ : 0) | TRACE_ADDR | ((reg_op1 + decoded_imm) & 32'hffffffff);
trace_data <= TRACE_ADDR | ((reg_op1 + decoded_imm) & 32'hffffffff);
end
reg_op1 <= reg_op1 + decoded_imm;
set_mem_do_wdata = 1;
@ -1271,7 +1134,7 @@ module picorv32 #(
latched_is_lb <= instr_lb;
if (ENABLE_TRACE) begin
trace_valid <= 1;
trace_data <= (irq_active ? TRACE_IRQ : 0) | TRACE_ADDR | ((reg_op1 + decoded_imm) & 32'hffffffff);
trace_data <= TRACE_ADDR | ((reg_op1 + decoded_imm) & 32'hffffffff);
end
reg_op1 <= reg_op1 + decoded_imm;
set_mem_do_rdata = 1;
@ -1291,28 +1154,19 @@ module picorv32 #(
end
endcase
next_irq_pending = next_irq_pending | irq;
if (timer) if (timer - 1 == 0) next_irq_pending[irq_timer] = 1;
if (resetn && (mem_do_rdata || mem_do_wdata)) begin
if (mem_wordsize == 0 && reg_op1[1:0] != 0) begin
`debug($display("MISALIGNED WORD: 0x%08x", reg_op1);)
if (!irq_mask[irq_buserror] && !irq_active) begin
next_irq_pending[irq_buserror] = 1;
end else cpu_state <= cpu_state_trap;
cpu_state <= cpu_state_trap;
end
if (mem_wordsize == 1 && reg_op1[0] != 0) begin
`debug($display("MISALIGNED HALFWORD: 0x%08x", reg_op1);)
if (!irq_mask[irq_buserror] && !irq_active) begin
next_irq_pending[irq_buserror] = 1;
end else cpu_state <= cpu_state_trap;
cpu_state <= cpu_state_trap;
end
end
if (resetn && mem_do_rinst && (|reg_pc[1:0])) begin
`debug($display("MISALIGNED INSTRUCTION: 0x%08x", reg_pc);)
if (!irq_mask[irq_buserror] && !irq_active) begin
next_irq_pending[irq_buserror] = 1;
end else cpu_state <= cpu_state_trap;
cpu_state <= cpu_state_trap;
end
if (!resetn || mem_done) begin
@ -1326,7 +1180,6 @@ module picorv32 #(
if (set_mem_do_rdata) mem_do_rdata <= 1;
if (set_mem_do_wdata) mem_do_wdata <= 1;
irq_pending <= next_irq_pending & ~MASKED_IRQ;
current_pc = 'bx;
end
endmodule
@ -1334,15 +1187,15 @@ endmodule
module picorv32_regs (
input clk,
wen,
input [5:0] waddr,
input [5:0] raddr1,
input [5:0] raddr2,
input [4:0] waddr,
input [4:0] raddr1,
input [4:0] raddr2,
input [31:0] wdata,
output [31:0] rdata1,
output [31:0] rdata2
);
reg [31:0] regs[0:35];
always @(posedge clk) if (wen) regs[waddr[5:0]] <= wdata;
reg [31:0] regs[0:31];
always @(posedge clk) if (wen) regs[waddr[4:0]] <= wdata;
assign rdata1 = regs[raddr1];
assign rdata2 = regs[raddr2];
endmodule

5
testbench_wb.v
View File

@ -113,10 +113,7 @@ module picorv32_wb #(
picorv32 #(
.ENABLE_TRACE(1),
.MASKED_IRQ(32'h0000_0000),
.LATCHED_IRQ(32'hffff_ffff),
.PROGADDR_RESET(32'h0001_0000),
.PROGADDR_IRQ(32'h0001_0010),
.STACKADDR(32'h0001_0000)
) picorv32_core (
.clk (clk),
@ -135,8 +132,6 @@ module picorv32_wb #(
.mem_la_addr (mem_la_addr),
.mem_la_wdata(mem_la_wdata),
.mem_la_wstrb(mem_la_wstrb),
.irq (irq),
.eoi (eoi),
.trace_valid(trace_valid),
.trace_data (trace_data),