diff options
| -rw-r--r-- | Makefile | 6 | ||||
| -rw-r--r-- | README.md | 66 | ||||
| -rw-r--r-- | firmware/custom_ops.S | 36 | ||||
| -rw-r--r-- | firmware/firmware.h | 7 | ||||
| -rw-r--r-- | firmware/irq.c | 6 | ||||
| -rw-r--r-- | firmware/makehex.py | 7 | ||||
| -rw-r--r-- | firmware/multest.c | 7 | ||||
| -rw-r--r-- | firmware/print.c | 6 | ||||
| -rw-r--r-- | firmware/sections.lds | 9 | ||||
| -rw-r--r-- | firmware/sieve.c | 7 | ||||
| -rw-r--r-- | firmware/start.S | 95 | ||||
| -rw-r--r-- | firmware/stats.c | 7 |
12 files changed, 182 insertions, 77 deletions
@@ -47,9 +47,9 @@ tests/%.o: tests/%.S tests/riscv_test.h tests/test_macros.h -DTEST_FUNC_TXT='"$(notdir $(basename $<))"' -DTEST_FUNC_RET=$(notdir $(basename $<))_ret $< clean: - rm -vrf $(TEST_OBJS) firmware/firmware.elf firmware/firmware.bin firmware/firmware.hex \ - firmware/firmware.map testbench*.exe testbench.vcd .Xil fsm_encoding.os \ - synth_vivado.log synth_vivado_*.backup.log synth_vivado.v + rm -vrf $(FIRMWARE_OBJS) $(TEST_OBJS) \ + firmware/firmware.{elf,bin,hex,map} \ + testbench{,_sp,_axi}.exe testbench.vcd .PHONY: test test_sp test_axi clean @@ -206,53 +206,51 @@ one bit is set in `q1`. Registers `q2` and `q3` are uninitialized and can be used as temporary storage when saving/restoring register values in the IRQ handler. -All of the following instructions are encoded under the `custom0` opcode. +All of the following instructions are encoded under the `custom0` opcode. The f3 +and rs2 fields are ignored in all this instructions. + +See [firmware/custom_ops.S](firmware/custom_ops.S) for GNU assembler macros that +implement mnemonics for this instructions. + +See [firmware/start.S](firmware/start.S) for an example implementaion of an +interrupt handler assember wrapper, and [firmware/irq.c](firmware/irq.c) for +the actual interrupt handler. #### getq rd, qs This instruction copies the value from a q-register to a general-purpose register. - 0000000 00000 000XX 000 XXXXX 0001011 + 0000000 ----- 000XX --- XXXXX 0001011 f7 rs2 qs f3 rd opcode -Example assembler code using the `custom0` mnemonic: +Example: -| Instruction | Assember Code | -| ------------------| --------------------| -| getq x5, q2 | custom0 5, 2, 0, 0 | -| getq x3, q0 | custom0 3, 0, 0, 0 | -| getq x1, q3 | custom0 1, 3, 0, 0 | + getq x5, q2 #### setq qd, rs This instruction copies the value from a general-purpose register to a q-register. - 0000001 00000 XXXXX 000 000XX 0001011 + 0000001 ----- XXXXX --- 000XX 0001011 f7 rs2 rs f3 qd opcode -Example assembler code using the `custom0` mnemonic: +Example: -| Instruction | Assember Code | -| ------------------| --------------------| -| setq q2, x5 | custom0 2, 5, 0, 1 | -| setq q0, x3 | custom0 0, 3, 0, 1 | -| setq q3, x1 | custom0 3, 1, 0, 1 | + setq q2, x5 #### retirq Return from interrupt. This instruction copies the value from `q0` to the program counter and re-enables interrupts. - 0000010 00000 00000 000 00000 0001011 + 0000010 ----- 00000 --- 00000 0001011 f7 rs2 rs f3 rd opcode -Example assembler code using the `custom0` mnemonic: +Example: -| Instruction | Assember Code | -| ------------------| --------------------| -| retirq | custom0 0, 0, 0, 2 | + retirq #### maskirq @@ -260,14 +258,12 @@ The "IRQ Mask" register contains a bitmask of masked (disabled) interrupts. This instruction writes a new value to the irq mask register and reads the old value. - 0000011 00000 XXXXX 000 XXXXX 0001011 + 0000011 ----- XXXXX --- XXXXX 0001011 f7 rs2 rs f3 rd opcode -Example assembler code using the `custom0` mnemonic: +Example: -| Instruction | Assember Code | -| ------------------| --------------------| -| maskirq x1, x2 | custom0 1, 2, 0, 3 | + maskirq x1, x2 The processor starts with all interrupts disabled. @@ -276,17 +272,15 @@ interrupt is disabled will cause the processor to halt. #### waitirq -Pause execution until an interrupt triggers. The bitmask of pending IRQs is -written to `rd`. +Pause execution until an interrupt becomes pending. The bitmask of pending IRQs +is written to `rd`. - 0000100 00000 00000 000 XXXXX 0001011 + 0000100 ----- 00000 --- XXXXX 0001011 f7 rs2 rs f3 rd opcode -Example assembler code using the `custom0` mnemonic: +Example: -| Instruction | Assember Code | -| ------------------| --------------------| -| waitirq x1 | custom0 1, 0, 0, 4 | + waitirq x1 #### timer @@ -295,14 +289,12 @@ triggers the timer interrupt when transitioning from 1 to 0. Setting the counter to zero disables the timer. The old value of the counter is written to `rd`. - 0000101 00000 XXXXX 000 XXXXX 0001011 + 0000101 ----- XXXXX --- XXXXX 0001011 f7 rs2 rs f3 rd opcode -Example assembler code using the `custom0` mnemonic: +Example: -| Instruction | Assember Code | -| ------------------| --------------------| -| timer x1, x2 | custom0 1, 2, 0, 5 | + timer x1, x2 Building a pure RV32I Toolchain: diff --git a/firmware/custom_ops.S b/firmware/custom_ops.S new file mode 100644 index 0000000..b5ea7ba --- /dev/null +++ b/firmware/custom_ops.S @@ -0,0 +1,36 @@ +// 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. + +#define q0 0 +#define q1 1 +#define q2 2 +#define q3 3 + +.macro getq rd qs +custom0 \rd,\qs,0,0 +.endm + +.macro setq qd rs +custom0 \qd,\rs,0,1 +.endm + +.macro retirq +custom0 0,0,0,2 +.endm + +.macro maskirq rd rs +custom0 \rd,\rs,0,3 +.endm + +.macro waitirq rd +custom0 \rd,0,0,4 +.endm + +.macro timer rd rs +custom0 \rd,\rs,0,5 +.endm + diff --git a/firmware/firmware.h b/firmware/firmware.h index b4fa4f8..3faf147 100644 --- a/firmware/firmware.h +++ b/firmware/firmware.h @@ -1,3 +1,10 @@ +// 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. + #ifndef FIRMWARE_H #define FIRMWARE_H diff --git a/firmware/irq.c b/firmware/irq.c index e49ef47..997e439 100644 --- a/firmware/irq.c +++ b/firmware/irq.c @@ -1,3 +1,9 @@ +// 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" diff --git a/firmware/makehex.py b/firmware/makehex.py index a5ae740..e1acdeb 100644 --- a/firmware/makehex.py +++ b/firmware/makehex.py @@ -1,4 +1,11 @@ #!/usr/bin/python3 +# +# 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. from sys import argv diff --git a/firmware/multest.c b/firmware/multest.c index 3d41267..6acf1e3 100644 --- a/firmware/multest.c +++ b/firmware/multest.c @@ -1,3 +1,10 @@ +// 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 xorshift32() { diff --git a/firmware/print.c b/firmware/print.c index 03e9b09..2aef715 100644 --- a/firmware/print.c +++ b/firmware/print.c @@ -1,3 +1,9 @@ +// 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" diff --git a/firmware/sections.lds b/firmware/sections.lds index 5e6e40c..f6d9a3b 100644 --- a/firmware/sections.lds +++ b/firmware/sections.lds @@ -1,3 +1,12 @@ +/* +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. +*/ + SECTIONS { .memory : { . = 0x000000; diff --git a/firmware/sieve.c b/firmware/sieve.c index 10fd1e0..9f7f7a3 100644 --- a/firmware/sieve.c +++ b/firmware/sieve.c @@ -1,3 +1,10 @@ +// 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. + // A simple Sieve of Eratosthenes #include "firmware.h" diff --git a/firmware/start.S b/firmware/start.S index a61f7fc..f39665e 100644 --- a/firmware/start.S +++ b/firmware/start.S @@ -1,8 +1,17 @@ +// 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. + #define ENABLE_RVTST #define ENABLE_SIEVE #define ENABLE_MULTST #define ENABLE_STATS +#include "custom_ops.S" + .section .text .global irq .global sieve @@ -13,43 +22,33 @@ .global hard_mulhu .global stats -#ifdef ENABLE_RVTST -# define TEST(n) \ - .global n; \ - addi x1, zero, 1000; \ - custom0 0,1,0,5; /* timer zero, x1 */ \ - jal zero,n; \ - .global n ## _ret; \ - n ## _ret: -#else -# define TEST(n) \ - .global n ## _ret; \ - n ## _ret: -#endif - reset_vec: - custom0 0,0,0,4 // waitirq zero - custom0 0,0,0,3 // maskirq zero, zero + // no more than 16 bytes here ! + waitirq zero + maskirq zero, zero j start - nop - nop + +/* Interrupt handler + **********************************/ + +.balign 16 irq_vec: /* save registers */ - custom0 2,1,0,1 // setq q2, x1 - custom0 3,2,0,1 // setq q3, x2 + setq q2, x1 + setq q3, x2 lui x1, %hi(irq_regs) addi x1, x1, %lo(irq_regs) - custom0 2,0,0,0 // getq x2, q0 + getq x2, q0 sw x2, 0*4(x1) - custom0 2,2,0,0 // getq x2, q2 + getq x2, q2 sw x2, 1*4(x1) - custom0 2,3,0,0 // getq x2, q3 + getq x2, q3 sw x2, 2*4(x1) sw x3, 3*4(x1) @@ -82,19 +81,19 @@ irq_vec: sw x30, 30*4(x1) sw x31, 31*4(x1) - /* call interrupt handler */ + /* call interrupt handler C function */ - lui sp, %hi(irq_stack_top) - addi sp, sp, %lo(irq_stack_top) + 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 - custom0 11,1,0,0 // getq x11, q1 + getq x11, q1 - // call to c function + // call to C function jal ra, irq /* restore registers */ @@ -103,13 +102,13 @@ irq_vec: addi x1, x1, %lo(irq_regs) lw x2, 0*4(x1) - custom0 0,2,0,1 // setq q0, x2 + setq q0, x2 lw x2, 1*4(x1) - custom0 1,2,0,1 // setq q1, x2 + setq q1, x2 lw x2, 2*4(x1) - custom0 2,2,0,1 // setq q2, x2 + setq q2, x2 lw x3, 3*4(x1) lw x4, 4*4(x1) @@ -141,21 +140,27 @@ irq_vec: lw x30, 30*4(x1) lw x31, 31*4(x1) - custom0 1,1,0,0 // getq x1, q1 - custom0 2,2,0,0 // getq x2, q2 + getq x1, q1 + getq x2, q2 - custom0 0,0,0,2 // retirq + retirq irq_regs: - // registers are saved to this memory region + // registers are saved to this memory region during interrupt handling // the program counter is saved as register 0 .fill 32,4 -irq_stack: + // stack for the interrupt handler .fill 128,4 -irq_stack_top: +irq_stack: + + +/* Main program + **********************************/ start: + /* zero-initialize all registers */ + addi x1, zero, 0 addi x2, zero, 0 addi x3, zero, 0 @@ -188,6 +193,22 @@ start: addi x30, zero, 0 addi x31, zero, 0 + /* running tests from riscv-tests */ + +#ifdef ENABLE_RVTST +# define TEST(n) \ + .global n; \ + addi x1, zero, 1000; \ + timer zero, x1; \ + jal zero,n; \ + .global n ## _ret; \ + n ## _ret: +#else +# define TEST(n) \ + .global n ## _ret; \ + n ## _ret: +#endif + TEST(lui) TEST(auipc) TEST(j) diff --git a/firmware/stats.c b/firmware/stats.c index 21f97d5..7c4434a 100644 --- a/firmware/stats.c +++ b/firmware/stats.c @@ -1,3 +1,10 @@ +// 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" static void stats_print_dec(int val, int digits, bool zero_pad) |