compiler,riscv: implement CSR operations as intrinsics

CSR operations must be implemented in assembly. The easiest way to
implement them is with some custom intrinsics in the compiler.
Этот коммит содержится в:
Ayke van Laethem 2020-01-06 19:57:48 +01:00 коммит произвёл Ron Evans
родитель ed9b2dbc03
коммит 360923abbf
3 изменённых файлов: 324 добавлений и 0 удалений

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@ -1306,6 +1306,8 @@ func (c *Compiler) parseCall(frame *Frame, instr *ssa.CallCommon) (llvm.Value, e
return c.emitAsmFull(frame, instr)
case strings.HasPrefix(name, "device/arm.SVCall"):
return c.emitSVCall(frame, instr.Args)
case strings.HasPrefix(name, "(device/riscv.CSR)."):
return c.emitCSROperation(frame, instr)
case strings.HasPrefix(name, "syscall.Syscall"):
return c.emitSyscall(frame, instr)
case strings.HasPrefix(name, "runtime/volatile.Load"):

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@ -162,3 +162,48 @@ func (c *Compiler) emitSVCall(frame *Frame, args []ssa.Value) (llvm.Value, error
target := llvm.InlineAsm(fnType, asm, constraints, true, false, 0)
return c.builder.CreateCall(target, llvmArgs, ""), nil
}
// This is a compiler builtin which emits CSR instructions. It can be one of:
//
// func (csr CSR) Get() uintptr
// func (csr CSR) Set(uintptr)
// func (csr CSR) SetBits(uintptr) uintptr
// func (csr CSR) ClearBits(uintptr) uintptr
//
// The csr parameter (method receiver) must be a constant. Other parameter can
// be any value.
func (c *Compiler) emitCSROperation(frame *Frame, call *ssa.CallCommon) (llvm.Value, error) {
csrConst, ok := call.Args[0].(*ssa.Const)
if !ok {
return llvm.Value{}, c.makeError(call.Pos(), "CSR must be constant")
}
csr := csrConst.Uint64()
switch name := call.StaticCallee().Name(); name {
case "Get":
// Note that this instruction may have side effects, and thus must be
// marked as such.
fnType := llvm.FunctionType(c.uintptrType, nil, false)
asm := fmt.Sprintf("csrr $0, %d", csr)
target := llvm.InlineAsm(fnType, asm, "=r", true, false, 0)
return c.builder.CreateCall(target, nil, ""), nil
case "Set":
fnType := llvm.FunctionType(c.ctx.VoidType(), []llvm.Type{c.uintptrType}, false)
asm := fmt.Sprintf("csrw %d, $0", csr)
target := llvm.InlineAsm(fnType, asm, "r", true, false, 0)
return c.builder.CreateCall(target, []llvm.Value{c.getValue(frame, call.Args[1])}, ""), nil
case "SetBits":
// Note: it may be possible to optimize this to csrrsi in many cases.
fnType := llvm.FunctionType(c.uintptrType, []llvm.Type{c.uintptrType}, false)
asm := fmt.Sprintf("csrrs $0, %d, $1", csr)
target := llvm.InlineAsm(fnType, asm, "=r,r", true, false, 0)
return c.builder.CreateCall(target, []llvm.Value{c.getValue(frame, call.Args[1])}, ""), nil
case "ClearBits":
// Note: it may be possible to optimize this to csrrci in many cases.
fnType := llvm.FunctionType(c.uintptrType, []llvm.Type{c.uintptrType}, false)
asm := fmt.Sprintf("csrrc $0, %d, $1", csr)
target := llvm.InlineAsm(fnType, asm, "=r,r", true, false, 0)
return c.builder.CreateCall(target, []llvm.Value{c.getValue(frame, call.Args[1])}, ""), nil
default:
return llvm.Value{}, c.makeError(call.Pos(), "unknown CSR operation: "+name)
}
}

277
src/device/riscv/csr.go Обычный файл
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@ -0,0 +1,277 @@
package riscv
// This file lists constants for CSR operations and defines methods on CSRs that
// are implemented as compiler intrinsics.
// CSR constants are used for use in CSR (Control and Status Register) compiler
// intrinsics.
type CSR int16
// Get returns the value of the given CSR.
func (csr CSR) Get() uintptr
// Set stores a new value in the given CSR.
func (csr CSR) Set(uintptr)
// SetBits atomically sets the given bits in this ISR and returns the old value.
func (csr CSR) SetBits(uintptr) uintptr
// ClearBits atomically clears the given bits in this ISR and returns the old
// value.
func (csr CSR) ClearBits(uintptr) uintptr
// CSR values defined in the RISC-V privileged specification. Not all values may
// be available on any given chip.
//
// Source: https://github.com/riscv/riscv-isa-manual/blob/riscv-priv-1.10/src/priv-csrs.tex
const (
// User Trap Setup
USTATUS CSR = 0x000 // User status register.
UIE CSR = 0x004 // User interrupt-enable register.
UTVEC CSR = 0x005 // User trap handler base address.
// User Trap Handling
USCRATCH CSR = 0x040 // Scratch register for user trap handlers.
UEPC CSR = 0x041 // User exception program counter.
UCAUSE CSR = 0x042 // User trap cause.
UTVAL CSR = 0x043 // User bad address or instruction.
UIP CSR = 0x044 // User interrupt pending.
// User Floating-Point CSRs
FFLAGS CSR = 0x001 // Floating-Point Accrued Exceptions.
FRM CSR = 0x002 // Floating-Point Dynamic Rounding Mode.
FCSR CSR = 0x003 // Floating-Point Control and Status
// User Counter/Timers
CYCLE CSR = 0xC00 // Cycle counter for RDCYCLE instruction.
TIME CSR = 0xC01 // Timer for RDTIME instruction.
INSTRET CSR = 0xC02 // Instructions-retired counter for RDINSTRET instruction.
HPMCOUNTER3 CSR = 0xC03 // Performance-monitoring counter 3.
HPMCOUNTER4 CSR = 0xC04 // Performance-monitoring counter 4.
HPMCOUNTER5 CSR = 0xC05 // Performance-monitoring counter 5.
HPMCOUNTER6 CSR = 0xC06 // Performance-monitoring counter 6.
HPMCOUNTER7 CSR = 0xC07 // Performance-monitoring counter 7.
HPMCOUNTER8 CSR = 0xC08 // Performance-monitoring counter 8.
HPMCOUNTER9 CSR = 0xC09 // Performance-monitoring counter 9.
HPMCOUNTER10 CSR = 0xC0A // Performance-monitoring counter 10.
HPMCOUNTER11 CSR = 0xC0B // Performance-monitoring counter 11.
HPMCOUNTER12 CSR = 0xC0C // Performance-monitoring counter 12.
HPMCOUNTER13 CSR = 0xC0D // Performance-monitoring counter 13.
HPMCOUNTER14 CSR = 0xC0E // Performance-monitoring counter 14.
HPMCOUNTER15 CSR = 0xC0F // Performance-monitoring counter 15.
HPMCOUNTER16 CSR = 0xC10 // Performance-monitoring counter 16.
HPMCOUNTER17 CSR = 0xC11 // Performance-monitoring counter 17.
HPMCOUNTER18 CSR = 0xC12 // Performance-monitoring counter 18.
HPMCOUNTER19 CSR = 0xC13 // Performance-monitoring counter 19.
HPMCOUNTER20 CSR = 0xC14 // Performance-monitoring counter 20.
HPMCOUNTER21 CSR = 0xC15 // Performance-monitoring counter 21.
HPMCOUNTER22 CSR = 0xC16 // Performance-monitoring counter 22.
HPMCOUNTER23 CSR = 0xC17 // Performance-monitoring counter 23.
HPMCOUNTER24 CSR = 0xC18 // Performance-monitoring counter 24.
HPMCOUNTER25 CSR = 0xC19 // Performance-monitoring counter 25.
HPMCOUNTER26 CSR = 0xC1A // Performance-monitoring counter 26.
HPMCOUNTER27 CSR = 0xC1B // Performance-monitoring counter 27.
HPMCOUNTER28 CSR = 0xC1C // Performance-monitoring counter 28.
HPMCOUNTER29 CSR = 0xC1D // Performance-monitoring counter 29.
HPMCOUNTER30 CSR = 0xC1E // Performance-monitoring counter 30.
HPMCOUNTER31 CSR = 0xC1F // Performance-monitoring counter 31.
CYCLEH CSR = 0xC80 // Upper 32 bits of CYCLE, RV32I only.
TIMEH CSR = 0xC81 // Upper 32 bits of TIME, RV32I only.
INSTRETH CSR = 0xC82 // Upper 32 bits of INSTRET, RV32I only.
HPMCOUNTER3H CSR = 0xC83 // Upper 32 bits of HPMCOUNTER3, RV32I only.
HPMCOUNTER4H CSR = 0xC84 // Upper 32 bits of HPMCOUNTER4, RV32I only.
HPMCOUNTER5H CSR = 0xC85 // Upper 32 bits of HPMCOUNTER5, RV32I only.
HPMCOUNTER6H CSR = 0xC86 // Upper 32 bits of HPMCOUNTER6, RV32I only.
HPMCOUNTER7H CSR = 0xC87 // Upper 32 bits of HPMCOUNTER7, RV32I only.
HPMCOUNTER8H CSR = 0xC88 // Upper 32 bits of HPMCOUNTER8, RV32I only.
HPMCOUNTER9H CSR = 0xC89 // Upper 32 bits of HPMCOUNTER9, RV32I only.
HPMCOUNTER10H CSR = 0xC8A // Upper 32 bits of HPMCOUNTER10, RV32I only.
HPMCOUNTER11H CSR = 0xC8B // Upper 32 bits of HPMCOUNTER11, RV32I only.
HPMCOUNTER12H CSR = 0xC8C // Upper 32 bits of HPMCOUNTER12, RV32I only.
HPMCOUNTER13H CSR = 0xC8D // Upper 32 bits of HPMCOUNTER13, RV32I only.
HPMCOUNTER14H CSR = 0xC8E // Upper 32 bits of HPMCOUNTER14, RV32I only.
HPMCOUNTER15H CSR = 0xC8F // Upper 32 bits of HPMCOUNTER15, RV32I only.
HPMCOUNTER16H CSR = 0xC90 // Upper 32 bits of HPMCOUNTER16, RV32I only.
HPMCOUNTER17H CSR = 0xC91 // Upper 32 bits of HPMCOUNTER17, RV32I only.
HPMCOUNTER18H CSR = 0xC92 // Upper 32 bits of HPMCOUNTER18, RV32I only.
HPMCOUNTER19H CSR = 0xC93 // Upper 32 bits of HPMCOUNTER19, RV32I only.
HPMCOUNTER20H CSR = 0xC94 // Upper 32 bits of HPMCOUNTER20, RV32I only.
HPMCOUNTER21H CSR = 0xC95 // Upper 32 bits of HPMCOUNTER21, RV32I only.
HPMCOUNTER22H CSR = 0xC96 // Upper 32 bits of HPMCOUNTER22, RV32I only.
HPMCOUNTER23H CSR = 0xC97 // Upper 32 bits of HPMCOUNTER23, RV32I only.
HPMCOUNTER24H CSR = 0xC98 // Upper 32 bits of HPMCOUNTER24, RV32I only.
HPMCOUNTER25H CSR = 0xC99 // Upper 32 bits of HPMCOUNTER25, RV32I only.
HPMCOUNTER26H CSR = 0xC9A // Upper 32 bits of HPMCOUNTER26, RV32I only.
HPMCOUNTER27H CSR = 0xC9B // Upper 32 bits of HPMCOUNTER27, RV32I only.
HPMCOUNTER28H CSR = 0xC9C // Upper 32 bits of HPMCOUNTER28, RV32I only.
HPMCOUNTER29H CSR = 0xC9D // Upper 32 bits of HPMCOUNTER29, RV32I only.
HPMCOUNTER30H CSR = 0xC9E // Upper 32 bits of HPMCOUNTER30, RV32I only.
HPMCOUNTER31H CSR = 0xC9F // Upper 32 bits of HPMCOUNTER31, RV32I only.
// Supervisor Trap Setup
SSTATUS CSR = 0x100 // Supervisor status register.
SEDELEG CSR = 0x102 // Supervisor exception delegation register.
SIDELEG CSR = 0x103 // Supervisor interrupt delegation register.
SIE CSR = 0x104 // Supervisor interrupt-enable register.
STVEC CSR = 0x105 // Supervisor trap handler base address.
SCOUNTEREN CSR = 0x106 // Supervisor counter enable.
// Supervisor Trap Handling
SSCRATCH CSR = 0x140 // Scratch register for supervisor trap handlers.
SEPC CSR = 0x141 // Supervisor exception program counter.
SCAUSE CSR = 0x142 // Supervisor trap cause.
STVAL CSR = 0x143 // Supervisor bad address or instruction.
SIP CSR = 0x144 // Supervisor interrupt pending.
// Supervisor Protection and Translation
SATP CSR = 0x180 // Supervisor address translation and protection.
// Machine Information Registers
MVENDORID CSR = 0xF11 // Vendor ID.
MARCHID CSR = 0xF12 // Architecture ID.
MIMPID CSR = 0xF13 // Implementation ID.
MHARTID CSR = 0xF14 // Hardware thread ID.
// Machine Trap Setup
MSTATUS CSR = 0x300 // Machine status register.
MISA CSR = 0x301 // ISA and extensions
MEDELEG CSR = 0x302 // Machine exception delegation register.
MIDELEG CSR = 0x303 // Machine interrupt delegation register.
MIE CSR = 0x304 // Machine interrupt-enable register.
MTVEC CSR = 0x305 // Machine trap-handler base address.
MCOUNTEREN CSR = 0x306 // Machine counter enable.
// Machine Trap Handling
MSCRATCH CSR = 0x340 // Scratch register for machine trap handlers.
MEPC CSR = 0x341 // Machine exception program counter.
MCAUSE CSR = 0x342 // Machine trap cause.
MTVAL CSR = 0x343 // Machine bad address or instruction.
MIP CSR = 0x344 // Machine interrupt pending.
// Machine Protection and Translation
PMPCFG0 CSR = 0x3A0 // Physical memory protection configuration.
PMPCFG1 CSR = 0x3A1 // Physical memory protection configuration, RV32 only.
PMPCFG2 CSR = 0x3A2 // Physical memory protection configuration.
PMPCFG3 CSR = 0x3A3 // Physical memory protection configuration, RV32 only.
PMPADDR0 CSR = 0x3B0 // Physical memory protection address register 0.
PMPADDR1 CSR = 0x3B1 // Physical memory protection address register 1.
PMPADDR2 CSR = 0x3B2 // Physical memory protection address register 2.
PMPADDR3 CSR = 0x3B3 // Physical memory protection address register 3.
PMPADDR4 CSR = 0x3B4 // Physical memory protection address register 4.
PMPADDR5 CSR = 0x3B5 // Physical memory protection address register 5.
PMPADDR6 CSR = 0x3B6 // Physical memory protection address register 6.
PMPADDR7 CSR = 0x3B7 // Physical memory protection address register 7.
PMPADDR8 CSR = 0x3B8 // Physical memory protection address register 8.
PMPADDR9 CSR = 0x3B9 // Physical memory protection address register 9.
PMPADDR10 CSR = 0x3BA // Physical memory protection address register 10.
PMPADDR11 CSR = 0x3BB // Physical memory protection address register 11.
PMPADDR12 CSR = 0x3BC // Physical memory protection address register 12.
PMPADDR13 CSR = 0x3BD // Physical memory protection address register 13.
PMPADDR14 CSR = 0x3BE // Physical memory protection address register 14.
PMPADDR15 CSR = 0x3BF // Physical memory protection address register 15.
// Machine Counter/Timers
mcycle CSR = 0xB00 // Machine cycle counter.
minstret CSR = 0xB02 // Machine instructions-retired counter.
MHPMCOUNTER3 CSR = 0xB03 // Machine performance-monitoring counter 3.
MHPMCOUNTER4 CSR = 0xB04 // Machine performance-monitoring counter 4.
MHPMCOUNTER5 CSR = 0xB05 // Machine performance-monitoring counter 5.
MHPMCOUNTER6 CSR = 0xB06 // Machine performance-monitoring counter 6.
MHPMCOUNTER7 CSR = 0xB07 // Machine performance-monitoring counter 7.
MHPMCOUNTER8 CSR = 0xB08 // Machine performance-monitoring counter 8.
MHPMCOUNTER9 CSR = 0xB09 // Machine performance-monitoring counter 9.
MHPMCOUNTER10 CSR = 0xB0A // Machine performance-monitoring counter 10.
MHPMCOUNTER11 CSR = 0xB0B // Machine performance-monitoring counter 11.
MHPMCOUNTER12 CSR = 0xB0C // Machine performance-monitoring counter 12.
MHPMCOUNTER13 CSR = 0xB0D // Machine performance-monitoring counter 13.
MHPMCOUNTER14 CSR = 0xB0E // Machine performance-monitoring counter 14.
MHPMCOUNTER15 CSR = 0xB0F // Machine performance-monitoring counter 15.
MHPMCOUNTER16 CSR = 0xB10 // Machine performance-monitoring counter 16.
MHPMCOUNTER17 CSR = 0xB11 // Machine performance-monitoring counter 17.
MHPMCOUNTER18 CSR = 0xB12 // Machine performance-monitoring counter 18.
MHPMCOUNTER19 CSR = 0xB13 // Machine performance-monitoring counter 19.
MHPMCOUNTER20 CSR = 0xB14 // Machine performance-monitoring counter 20.
MHPMCOUNTER21 CSR = 0xB15 // Machine performance-monitoring counter 21.
MHPMCOUNTER22 CSR = 0xB16 // Machine performance-monitoring counter 22.
MHPMCOUNTER23 CSR = 0xB17 // Machine performance-monitoring counter 23.
MHPMCOUNTER24 CSR = 0xB18 // Machine performance-monitoring counter 24.
MHPMCOUNTER25 CSR = 0xB19 // Machine performance-monitoring counter 25.
MHPMCOUNTER26 CSR = 0xB1A // Machine performance-monitoring counter 26.
MHPMCOUNTER27 CSR = 0xB1B // Machine performance-monitoring counter 27.
MHPMCOUNTER28 CSR = 0xB1C // Machine performance-monitoring counter 28.
MHPMCOUNTER29 CSR = 0xB1D // Machine performance-monitoring counter 29.
MHPMCOUNTER30 CSR = 0xB1E // Machine performance-monitoring counter 30.
MHPMCOUNTER31 CSR = 0xB1F // Machine performance-monitoring counter 31.
MCYCLEH CSR = 0xB80 // Upper 32 bits of MCYCLE, RV32I only.
MINSTRETH CSR = 0xB82 // Upper 32 bits of MINSTRET, RV32I only.
MHPMCOUNTER3H CSR = 0xB83 // Upper 32 bits of MHPMCOUNTER3, RV32I only.
MHPMCOUNTER4H CSR = 0xB84 // Upper 32 bits of MHPMCOUNTER4, RV32I only.
MHPMCOUNTER5H CSR = 0xB85 // Upper 32 bits of MHPMCOUNTER5, RV32I only.
MHPMCOUNTER6H CSR = 0xB86 // Upper 32 bits of MHPMCOUNTER6, RV32I only.
MHPMCOUNTER7H CSR = 0xB87 // Upper 32 bits of MHPMCOUNTER7, RV32I only.
MHPMCOUNTER8H CSR = 0xB88 // Upper 32 bits of MHPMCOUNTER8, RV32I only.
MHPMCOUNTER9H CSR = 0xB89 // Upper 32 bits of MHPMCOUNTER9, RV32I only.
MHPMCOUNTER10H CSR = 0xB8A // Upper 32 bits of MHPMCOUNTER10, RV32I only.
MHPMCOUNTER11H CSR = 0xB8B // Upper 32 bits of MHPMCOUNTER11, RV32I only.
MHPMCOUNTER12H CSR = 0xB8C // Upper 32 bits of MHPMCOUNTER12, RV32I only.
MHPMCOUNTER13H CSR = 0xB8D // Upper 32 bits of MHPMCOUNTER13, RV32I only.
MHPMCOUNTER14H CSR = 0xB8E // Upper 32 bits of MHPMCOUNTER14, RV32I only.
MHPMCOUNTER15H CSR = 0xB8F // Upper 32 bits of MHPMCOUNTER15, RV32I only.
MHPMCOUNTER16H CSR = 0xB90 // Upper 32 bits of MHPMCOUNTER16, RV32I only.
MHPMCOUNTER17H CSR = 0xB91 // Upper 32 bits of MHPMCOUNTER17, RV32I only.
MHPMCOUNTER18H CSR = 0xB92 // Upper 32 bits of MHPMCOUNTER18, RV32I only.
MHPMCOUNTER19H CSR = 0xB93 // Upper 32 bits of MHPMCOUNTER19, RV32I only.
MHPMCOUNTER20H CSR = 0xB94 // Upper 32 bits of MHPMCOUNTER20, RV32I only.
MHPMCOUNTER21H CSR = 0xB95 // Upper 32 bits of MHPMCOUNTER21, RV32I only.
MHPMCOUNTER22H CSR = 0xB96 // Upper 32 bits of MHPMCOUNTER22, RV32I only.
MHPMCOUNTER23H CSR = 0xB97 // Upper 32 bits of MHPMCOUNTER23, RV32I only.
MHPMCOUNTER24H CSR = 0xB98 // Upper 32 bits of MHPMCOUNTER24, RV32I only.
MHPMCOUNTER25H CSR = 0xB99 // Upper 32 bits of MHPMCOUNTER25, RV32I only.
MHPMCOUNTER26H CSR = 0xB9A // Upper 32 bits of MHPMCOUNTER26, RV32I only.
MHPMCOUNTER27H CSR = 0xB9B // Upper 32 bits of MHPMCOUNTER27, RV32I only.
MHPMCOUNTER28H CSR = 0xB9C // Upper 32 bits of MHPMCOUNTER28, RV32I only.
MHPMCOUNTER29H CSR = 0xB9D // Upper 32 bits of MHPMCOUNTER29, RV32I only.
MHPMCOUNTER30H CSR = 0xB9E // Upper 32 bits of MHPMCOUNTER30, RV32I only.
MHPMCOUNTER31H CSR = 0xB9F // Upper 32 bits of MHPMCOUNTER31, RV32I only.
// Machine Counter Setup
MHPMEVENT4 CSR = 0x324 // Machine performance-monitoring event selector 4.
MHPMEVENT5 CSR = 0x325 // Machine performance-monitoring event selector 5.
MHPMEVENT6 CSR = 0x326 // Machine performance-monitoring event selector 6.
MHPMEVENT7 CSR = 0x327 // Machine performance-monitoring event selector 7.
MHPMEVENT8 CSR = 0x328 // Machine performance-monitoring event selector 8.
MHPMEVENT9 CSR = 0x329 // Machine performance-monitoring event selector 9.
MHPMEVENT10 CSR = 0x32A // Machine performance-monitoring event selector 10.
MHPMEVENT11 CSR = 0x32B // Machine performance-monitoring event selector 11.
MHPMEVENT12 CSR = 0x32C // Machine performance-monitoring event selector 12.
MHPMEVENT13 CSR = 0x32D // Machine performance-monitoring event selector 13.
MHPMEVENT14 CSR = 0x32E // Machine performance-monitoring event selector 14.
MHPMEVENT15 CSR = 0x32F // Machine performance-monitoring event selector 15.
MHPMEVENT16 CSR = 0x330 // Machine performance-monitoring event selector 16.
MHPMEVENT17 CSR = 0x331 // Machine performance-monitoring event selector 17.
MHPMEVENT18 CSR = 0x332 // Machine performance-monitoring event selector 18.
MHPMEVENT19 CSR = 0x333 // Machine performance-monitoring event selector 19.
MHPMEVENT20 CSR = 0x334 // Machine performance-monitoring event selector 20.
MHPMEVENT21 CSR = 0x335 // Machine performance-monitoring event selector 21.
MHPMEVENT22 CSR = 0x336 // Machine performance-monitoring event selector 22.
MHPMEVENT23 CSR = 0x337 // Machine performance-monitoring event selector 23.
MHPMEVENT24 CSR = 0x338 // Machine performance-monitoring event selector 24.
MHPMEVENT25 CSR = 0x339 // Machine performance-monitoring event selector 25.
MHPMEVENT26 CSR = 0x33A // Machine performance-monitoring event selector 26.
MHPMEVENT27 CSR = 0x33B // Machine performance-monitoring event selector 27.
MHPMEVENT28 CSR = 0x33C // Machine performance-monitoring event selector 28.
MHPMEVENT29 CSR = 0x33D // Machine performance-monitoring event selector 29.
MHPMEVENT30 CSR = 0x33E // Machine performance-monitoring event selector 30.
MHPMEVENT31 CSR = 0x33F // Machine performance-monitoring event selector 31.
// Debug/Trace Registers (shared with Debug Mode)
TSELECT CSR = 0x7A0 // Debug/Trace trigger register select.
TDATA1 CSR = 0x7A1 // First Debug/Trace trigger data register.
TDATA2 CSR = 0x7A2 // Second Debug/Trace trigger data register.
TDATA3 CSR = 0x7A3 // Third Debug/Trace trigger data register.
// Debug Mode Registers
DCSR CSR = 0x7B0 // Debug control and status register.
DPC CSR = 0x7B1 // Debug PC.
DSCRATCH CSR = 0x7B2 // Debug scratch register.
)