/*
* Copyright (c) 2023, Sönke Holz <sholz8530@gmail.com>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <Kernel/API/RISCVExtensionBitmask.h>
#include <Kernel/Arch/Interrupts.h>
#include <Kernel/Arch/Processor.h>
#include <Kernel/Arch/TrapFrame.h>
#include <Kernel/Firmware/DeviceTree/DeviceTree.h>
#include <Kernel/Interrupts/InterruptDisabler.h>
#include <Kernel/Library/Panic.h>
#include <Kernel/Sections.h>
#include <Kernel/Security/Random.h>
#include <Kernel/Tasks/Process.h>
#include <Kernel/Tasks/Scheduler.h>
namespace Kernel {
extern "C" u8 asm_trap_handler[];
Processor* g_current_processor;
static void store_vector_state(FPUState* fpu_state)
{
fpu_state->vstart = RISCV64::CSR::read<RISCV64::CSR::Address::VSTART_>();
fpu_state->vcsr = RISCV64::CSR::read<RISCV64::CSR::Address::VCSR>();
fpu_state->vl = RISCV64::CSR::read<RISCV64::CSR::Address::VL>();
fpu_state->vtype = RISCV64::CSR::read<RISCV64::CSR::Address::VTYPE>();
asm volatile(R"(
.option push
.option arch, +v
csrr t0, vlenb
slli t0, t0, 3 # 8 registers at once (2^3 = 8)
csrw vstart, zero
# Save v0-v7.
vs8r.v v0, (%0)
add %0, %0, t0
# Save v8-v15.
vs8r.v v8, (%0)
add %0, %0, t0
# Save v16-v23.
vs8r.v v16, (%0)
add %0, %0, t0
# Save v24-v31.
vs8r.v v24, (%0)
.option pop
)" ::"r"(fpu_state->v)
: "t0", "memory");
}
static void load_vector_state(FPUState* fpu_state)
{
asm volatile(R"(
.option push
.option arch, +v
csrr t0, vlenb
slli t0, t0, 3 # 8 registers at once (2^3 = 8)
csrw vstart, zero
# Restore v0-v7.
vl8r.v v0, (%0)
add %0, %0, t0
# Restore v8-v15.
vl8r.v v8, (%0)
add %0, %0, t0
# Restore v16-v23.
vl8r.v v16, (%0)
add %0, %0, t0
# Restore v24-v31.
vl8r.v v24, (%0)
.option pop
)" ::"r"(fpu_state->v)
: "t0", "memory");
RISCV64::CSR::write<RISCV64::CSR::Address::VSTART_>(fpu_state->vstart);
RISCV64::CSR::write<RISCV64::CSR::Address::VCSR>(fpu_state->vcsr);
asm volatile(R"(
.option push
.option arch, +v
vsetvl zero, %[vl], %[vtype]
.option pop
)" ::[vl] "r"(fpu_state->vl),
[vtype] "r"(fpu_state->vtype));
}
static void store_fpu_state(FPUState* fpu_state)
{
asm volatile(
"fsd f0, 0*8(%0) \n"
"fsd f1, 1*8(%0) \n"
"fsd f2, 2*8(%0) \n"
"fsd f3, 3*8(%0) \n"
"fsd f4, 4*8(%0) \n"
"fsd f5, 5*8(%0) \n"
"fsd f6, 6*8(%0) \n"
"fsd f7, 7*8(%0) \n"
"fsd f8, 8*8(%0) \n"
"fsd f9, 9*8(%0) \n"
"fsd f10, 10*8(%0) \n"
"fsd f11, 11*8(%0) \n"
"fsd f12, 12*8(%0) \n"
"fsd f13, 13*8(%0) \n"
"fsd f14, 14*8(%0) \n"
"fsd f15, 15*8(%0) \n"
"fsd f16, 16*8(%0) \n"
"fsd f17, 17*8(%0) \n"
"fsd f18, 18*8(%0) \n"
"fsd f19, 19*8(%0) \n"
"fsd f20, 20*8(%0) \n"
"fsd f21, 21*8(%0) \n"
"fsd f22, 22*8(%0) \n"
"fsd f23, 23*8(%0) \n"
"fsd f24, 24*8(%0) \n"
"fsd f25, 25*8(%0) \n"
"fsd f26, 26*8(%0) \n"
"fsd f27, 27*8(%0) \n"
"fsd f28, 28*8(%0) \n"
"fsd f29, 29*8(%0) \n"
"fsd f30, 30*8(%0) \n"
"fsd f31, 31*8(%0) \n"
"csrr t0, fcsr \n"
"sd t0, 32*8(%0) \n" ::"r"(fpu_state)
: "t0", "memory");
if (Processor::current().has_feature(CPUFeature::V))
store_vector_state(fpu_state);
}
static void load_fpu_state(FPUState* fpu_state)
{
asm volatile(
"fld f0, 0*8(%0) \n"
"fld f1, 1*8(%0) \n"
"fld f2, 2*8(%0) \n"
"fld f3, 3*8(%0) \n"
"fld f4, 4*8(%0) \n"
"fld f5, 5*8(%0) \n"
"fld f6, 6*8(%0) \n"
"fld f7, 7*8(%0) \n"
"fld f8, 8*8(%0) \n"
"fld f9, 9*8(%0) \n"
"fld f10, 10*8(%0) \n"
"fld f11, 11*8(%0) \n"
"fld f12, 12*8(%0) \n"
"fld f13, 13*8(%0) \n"
"fld f14, 14*8(%0) \n"
"fld f15, 15*8(%0) \n"
"fld f16, 16*8(%0) \n"
"fld f17, 17*8(%0) \n"
"fld f18, 18*8(%0) \n"
"fld f19, 19*8(%0) \n"
"fld f20, 20*8(%0) \n"
"fld f21, 21*8(%0) \n"
"fld f22, 22*8(%0) \n"
"fld f23, 23*8(%0) \n"
"fld f24, 24*8(%0) \n"
"fld f25, 25*8(%0) \n"
"fld f26, 26*8(%0) \n"
"fld f27, 27*8(%0) \n"
"fld f28, 28*8(%0) \n"
"fld f29, 29*8(%0) \n"
"fld f30, 30*8(%0) \n"
"fld f31, 31*8(%0) \n"
"ld t0, 32*8(%0) \n"
"csrw fcsr, t0 \n" ::"r"(fpu_state)
: "t0", "memory");
if (Processor::current().has_feature(CPUFeature::V))
load_vector_state(fpu_state);
}
template<typename T>
void ProcessorBase<T>::early_initialize(u32 cpu)
{
VERIFY(g_current_processor == nullptr);
m_cpu = cpu;
g_current_processor = static_cast<Processor*>(this);
}
template<typename T>
void ProcessorBase<T>::initialize(u32)
{
m_deferred_call_pool.init();
// FIXME: Actually set the correct count when we support SMP on riscv64.
g_total_processors.store(1, AK::MemoryOrder::memory_order_release);
auto* self = static_cast<Processor*>(this);
self->m_info.emplace();
RISCV64::CSR::write<RISCV64::CSR::Address::STVEC>(bit_cast<FlatPtr>(+asm_trap_handler));
initialize_interrupts();
}
template<typename T>
[[noreturn]] void ProcessorBase<T>::halt()
{
// WFI ignores the value of sstatus.SIE, so we can't use disable_interrupts().
// Instead, disable all interrupts sources by setting sie to zero.
RISCV64::CSR::write<RISCV64::CSR::Address::SIE>(0);
for (;;)
asm volatile("wfi");
}
template<typename T>
void ProcessorBase<T>::flush_tlb_local(VirtualAddress vaddr, size_t page_count)
{
auto addr = vaddr.get();
while (page_count > 0) {
asm volatile("sfence.vma %0"
:
: "r"(addr)
: "memory");
addr += PAGE_SIZE;
page_count--;
}
}
template<typename T>
void ProcessorBase<T>::flush_entire_tlb_local()
{
asm volatile("sfence.vma");
}
template<typename T>
void ProcessorBase<T>::flush_tlb(Memory::PageDirectory const*, VirtualAddress vaddr, size_t page_count)
{
// FIXME: Use the SBI RFENCE extension to flush the TLB of other harts when we support SMP on riscv64.
flush_tlb_local(vaddr, page_count);
}
template<typename T>
void ProcessorBase<T>::flush_instruction_cache(VirtualAddress, size_t)
{
// FIXME: Use the SBI RFENCE extension to flush the instruction cache of other harts when we support SMP on riscv64.
asm volatile("fence.i" ::: "memory");
}
template<typename T>
u32 ProcessorBase<T>::clear_critical()
{
InterruptDisabler disabler;
auto prev_critical = in_critical();
auto& proc = current();
proc.m_in_critical = 0;
if (proc.m_in_irq == 0)
proc.check_invoke_scheduler();
return prev_critical;
}
template<typename T>
u32 ProcessorBase<T>::smp_wake_n_idle_processors(u32)
{
// FIXME: Actually wake up other cores when SMP is supported for riscv64.
return 0;
}
template<typename T>
void ProcessorBase<T>::initialize_context_switching(Thread& initial_thread)
{
VERIFY(initial_thread.process().is_kernel_process());
m_scheduler_initialized.set();
// FIXME: Figure out if we need to call {pre_,post_,}init_finished once riscv64 supports SMP
Processor::set_current_in_scheduler(true);
auto& regs = initial_thread.regs();
asm volatile(
"mv sp, %[new_sp] \n"
"addi sp, sp, -32 \n"
"sd %[from_to_thread], 0(sp) \n"
"sd %[from_to_thread], 8(sp) \n"
"jr %[new_ip] \n" ::[new_sp] "r"(regs.sp()),
[new_ip] "r"(regs.ip()),
[from_to_thread] "r"(&initial_thread)
: "t0");
VERIFY_NOT_REACHED();
}
template<typename T>
void ProcessorBase<T>::switch_context(Thread*& from_thread, Thread*& to_thread)
{
VERIFY(!m_in_irq);
VERIFY(m_in_critical == 1);
dbgln_if(CONTEXT_SWITCH_DEBUG, "switch_context --> switching out of: {} {}", VirtualAddress(from_thread), *from_thread);
// m_in_critical is restored in enter_thread_context
from_thread->save_critical(m_in_critical);
asm volatile(
// Store a RegisterState of from_thread on from_thread's stack
"addi sp, sp, -(34 * 8) \n"
"sd x1, 0*8(sp) \n"
// sp
"sd x3, 2*8(sp) \n"
"sd x4, 3*8(sp) \n"
"sd x5, 4*8(sp) \n"
"sd x6, 5*8(sp) \n"
"sd x7, 6*8(sp) \n"
"sd x8, 7*8(sp) \n"
"sd x9, 8*8(sp) \n"
"sd x10, 9*8(sp) \n"
"sd x11, 10*8(sp) \n"
"sd x12, 11*8(sp) \n"
"sd x13, 12*8(sp) \n"
"sd x14, 13*8(sp) \n"
"sd x15, 14*8(sp) \n"
"sd x16, 15*8(sp) \n"
"sd x17, 16*8(sp) \n"
"sd x18, 17*8(sp) \n"
"sd x19, 18*8(sp) \n"
"sd x20, 19*8(sp) \n"
"sd x21, 20*8(sp) \n"
"sd x22, 21*8(sp) \n"
"sd x23, 22*8(sp) \n"
"sd x24, 23*8(sp) \n"
"sd x25, 24*8(sp) \n"
"sd x26, 25*8(sp) \n"
"sd x27, 26*8(sp) \n"
"sd x28, 27*8(sp) \n"
"sd x29, 28*8(sp) \n"
"sd x30, 29*8(sp) \n"
"sd x31, 30*8(sp) \n"
// Store current sp as from_thread's sp.
"sd sp, %[from_sp] \n"
// Store current fp as from_thread's sp.
// This is needed to make capture_stack_trace() work.
"sd fp, %[from_fp] \n"
// Set from_thread's pc to label "1"
"la t0, 1f \n"
"sd t0, %[from_ip] \n"
// Switch to to_thread's stack
"ld sp, %[to_sp] \n"
// Store from_thread, to_thread, to_ip on to_thread's stack
"addi sp, sp, -(4 * 8) \n"
"ld a0, %[from_thread] \n"
"sd a0, 0*8(sp) \n"
"ld a1, %[to_thread] \n"
"sd a1, 1*8(sp) \n"
"ld s1, %[to_ip] \n"
"sd s1, 2*8(sp) \n"
// enter_thread_context(from_thread, to_thread)
"call enter_thread_context \n"
// Jump to to_ip
"jr s1 \n"
// A thread enters here when they were already scheduled at least once
"1: \n"
"addi sp, sp, (4 * 8) \n"
// Restore the RegisterState of to_thread
"ld x1, 0*8(sp) \n"
// sp
"ld x3, 2*8(sp) \n"
"ld x4, 3*8(sp) \n"
"ld x5, 4*8(sp) \n"
"ld x6, 5*8(sp) \n"
"ld x7, 6*8(sp) \n"
"ld x8, 7*8(sp) \n"
"ld x9, 8*8(sp) \n"
"ld x10, 9*8(sp) \n"
"ld x11, 10*8(sp) \n"
"ld x12, 11*8(sp) \n"
"ld x13, 12*8(sp) \n"
"ld x14, 13*8(sp) \n"
"ld x15, 14*8(sp) \n"
"ld x16, 15*8(sp) \n"
"ld x17, 16*8(sp) \n"
"ld x18, 17*8(sp) \n"
"ld x19, 18*8(sp) \n"
"ld x20, 19*8(sp) \n"
"ld x21, 20*8(sp) \n"
"ld x22, 21*8(sp) \n"
"ld x23, 22*8(sp) \n"
"ld x24, 23*8(sp) \n"
"ld x25, 24*8(sp) \n"
"ld x26, 25*8(sp) \n"
"ld x27, 26*8(sp) \n"
"ld x28, 27*8(sp) \n"
"ld x29, 28*8(sp) \n"
"ld x30, 29*8(sp) \n"
"ld x31, 30*8(sp) \n"
"addi sp, sp, -(4 * 8) \n"
"ld t0, 0*8(sp) \n"
"sd t0, %[from_thread] \n"
"ld t0, 1*8(sp) \n"
"sd t0, %[to_thread] \n"
"addi sp, sp, (34 * 8) + (4 * 8) \n"
:
[from_ip] "=m"(from_thread->regs().pc),
[from_sp] "=m"(from_thread->regs().x[1]),
[from_fp] "=m"(from_thread->regs().x[7]),
"=m"(from_thread),
"=m"(to_thread)
: [to_ip] "m"(to_thread->regs().pc),
[to_sp] "m"(to_thread->regs().x[1]),
[from_thread] "m"(from_thread),
[to_thread] "m"(to_thread)
: "memory", "t0", "s1", "a0", "a1");
dbgln_if(CONTEXT_SWITCH_DEBUG, "switch_context <-- from {} {} to {} {}", VirtualAddress(from_thread), *from_thread, VirtualAddress(to_thread), *to_thread);
}
extern "C" FlatPtr do_init_context(Thread* thread, u32 new_interrupts_state)
{
VERIFY_INTERRUPTS_DISABLED();
thread->regs().sstatus.SPIE = (new_interrupts_state == to_underlying(InterruptsState::Enabled));
return Processor::current().init_context(*thread, true);
}
template<typename T>
void ProcessorBase<T>::assume_context(Thread& thread, InterruptsState new_interrupts_state)
{
dbgln_if(CONTEXT_SWITCH_DEBUG, "Assume context for thread {} {}", VirtualAddress(&thread), thread);
VERIFY_INTERRUPTS_DISABLED();
Scheduler::prepare_after_exec();
// in_critical() should be 2 here. The critical section in Process::exec
// and then the scheduler lock
VERIFY(Processor::in_critical() == 2);
do_assume_context(&thread, to_underlying(new_interrupts_state));
VERIFY_NOT_REACHED();
}
template<typename T>
FlatPtr ProcessorBase<T>::init_context(Thread& thread, bool leave_crit)
{
VERIFY(g_scheduler_lock.is_locked());
if (leave_crit) {
// Leave the critical section we set up in Process::exec,
// but because we still have the scheduler lock we should end up with 1
VERIFY(in_critical() == 2);
m_in_critical = 1; // leave it without triggering anything or restoring flags
}
u64 kernel_stack_top = thread.kernel_stack_top();
// Add a random offset between 0-256 (16-byte aligned)
kernel_stack_top -= round_up_to_power_of_two(get_fast_random<u8>(), 16);
u64 stack_top = kernel_stack_top;
auto& thread_regs = thread.regs();
// Push a RegisterState and TrapFrame onto the stack, which will be popped of the stack and restored into the
// state of the processor by restore_previous_context.
stack_top -= sizeof(RegisterState);
RegisterState& frame = *reinterpret_cast<RegisterState*>(stack_top);
memcpy(frame.x, thread_regs.x, sizeof(thread_regs.x));
// We don't overwrite the return address register if it's not 0, since that means this thread's register state was already initialized with
// an existing return address register value (e.g. it was fork()'ed), so we assume exit_kernel_thread is already saved as previous RA on the
// stack somewhere.
if (frame.x[0] == 0x0) {
// x1 is the return address register for the riscv64 ABI, so this will return to exit_kernel_thread when main thread function returns.
frame.x[0] = FlatPtr(&exit_kernel_thread);
}
frame.sepc = thread_regs.pc;
frame.set_userspace_sp(thread_regs.sp());
frame.sstatus = thread_regs.sstatus;
// Push a TrapFrame onto the stack
stack_top -= sizeof(TrapFrame);
TrapFrame& trap = *reinterpret_cast<TrapFrame*>(stack_top);
trap.regs = &frame;
trap.next_trap = nullptr;
if constexpr (CONTEXT_SWITCH_DEBUG) {
dbgln("init_context {} ({}) set up to execute at ip={}, sp={}, stack_top={}",
thread,
VirtualAddress(&thread),
VirtualAddress(thread_regs.pc),
VirtualAddress(thread_regs.sp()),
VirtualAddress(stack_top));
}
// This make sure the thread first executes thread_context_first_enter, which will actually call restore_previous_context
// which restores the context set up above.
thread_regs.set_sp(stack_top);
thread_regs.set_ip(FlatPtr(&thread_context_first_enter));
return stack_top;
}
// FIXME: Figure out if we can fully share this code with x86.
template<typename T>
void ProcessorBase<T>::exit_trap(TrapFrame& trap)
{
VERIFY_INTERRUPTS_DISABLED();
VERIFY(&Processor::current() == this);
// Temporarily enter a critical section. This is to prevent critical
// sections entered and left within e.g. smp_process_pending_messages
// to trigger a context switch while we're executing this function
// See the comment at the end of the function why we don't use
// ScopedCritical here.
m_in_critical = m_in_critical + 1;
// FIXME: Figure out if we need prev_irq_level, see duplicated code in Kernel/Arch/x86/common/Processor.cpp
m_in_irq = 0;
// Process the deferred call queue. Among other things, this ensures
// that any pending thread unblocks happen before we enter the scheduler.
m_deferred_call_pool.execute_pending();
auto* current_thread = Processor::current_thread();
if (current_thread) {
auto& current_trap = current_thread->current_trap();
current_trap = trap.next_trap;
ExecutionMode new_previous_mode;
if (current_trap) {
VERIFY(current_trap->regs);
new_previous_mode = current_trap->regs->previous_mode();
} else {
// If we don't have a higher level trap then we're back in user mode.
// Which means that the previous mode prior to being back in user mode was kernel mode
new_previous_mode = ExecutionMode::Kernel;
}
if (current_thread->set_previous_mode(new_previous_mode))
current_thread->update_time_scheduled(TimeManagement::scheduler_current_time(), true, false);
}
VERIFY_INTERRUPTS_DISABLED();
// Leave the critical section without actually enabling interrupts.
// We don't want context switches to happen until we're explicitly
// triggering a switch in check_invoke_scheduler.
m_in_critical = m_in_critical - 1;
if (!m_in_irq && !m_in_critical)
check_invoke_scheduler();
}
extern "C" void context_first_init(Thread* from_thread, Thread* to_thread);
extern "C" void context_first_init(Thread* from_thread, Thread* to_thread)
{
do_context_first_init(from_thread, to_thread);
}
extern "C" void enter_thread_context(Thread* from_thread, Thread* to_thread);
extern "C" void enter_thread_context(Thread* from_thread, Thread* to_thread)
{
VERIFY(from_thread == to_thread || from_thread->state() != Thread::State::Running);
VERIFY(to_thread->state() == Thread::State::Running);
Processor::set_current_thread(*to_thread);
store_fpu_state(&from_thread->fpu_state());
auto& from_regs = from_thread->regs();
auto& to_regs = to_thread->regs();
if (from_regs.satp != to_regs.satp) {
RISCV64::CSR::SATP::write(to_regs.satp);
Processor::flush_entire_tlb_local();
}
to_thread->set_cpu(Processor::current().id());
auto in_critical = to_thread->saved_critical();
VERIFY(in_critical > 0);
Processor::restore_critical(in_critical);
load_fpu_state(&to_thread->fpu_state());
}
NAKED void thread_context_first_enter()
{
asm(
"ld a0, 0(sp) \n"
"ld a1, 8(sp) \n"
"addi sp, sp, 32 \n"
"call context_first_init \n"
"mv a0, sp \n"
"call exit_trap \n"
"tail restore_context_and_sret \n");
}
NAKED void do_assume_context(Thread*, u32)
{
// clang-format off
asm(
"mv s1, a0 \n" // save thread ptr
// We're going to call Processor::init_context, so just make sure
// we have enough stack space so we don't stomp over it
"addi sp, sp, -" __STRINGIFY(8 + REGISTER_STATE_SIZE + TRAP_FRAME_SIZE + 8) " \n"
"call do_init_context \n"
"mv sp, a0 \n" // move stack pointer to what Processor::init_context set up for us
"mv a0, s1 \n" // to_thread
"mv a1, s1 \n" // from_thread
"addi sp, sp, -32 \n"
"sd s1, 0(sp) \n"
"sd s1, 8(sp) \n"
"la ra, thread_context_first_enter \n" // should be same as regs.sepc
"tail enter_thread_context \n");
// clang-format on
}
template<typename T>
StringView ProcessorBase<T>::platform_string()
{
return "riscv64"sv;
}
template<typename T>
void ProcessorBase<T>::wait_for_interrupt() const
{
asm("wfi");
}
template<typename T>
Processor& ProcessorBase<T>::by_id(u32)
{
TODO_RISCV64();
}
void Processor::find_and_parse_devicetree_node()
{
// https://www.kernel.org/doc/Documentation/devicetree/bindings/riscv/cpus.yaml
// https://www.kernel.org/doc/Documentation/devicetree/bindings/riscv/extensions.yaml
// Find the CPU node for this hart.
auto cpus_node = DeviceTree::get().get_child("cpus"sv);
if (!cpus_node.has_value())
PANIC("No /cpus node in devicetree");
for (auto const& [cpu_name, cpu] : cpus_node->children()) {
auto device_type = cpu.get_property("device_type"sv);
if (!device_type.has_value() || device_type->as_string() != "cpu"sv)
continue;
if (!cpu.is_compatible_with("riscv"sv))
continue;
auto reg_or_error = cpu.reg();
if (reg_or_error.is_error())
continue;
auto reg = reg_or_error.release_value();
if (reg.entry_count() != 1)
PANIC("RISC-V CPU node {} has invalid reg element count: {}", cpu_name, reg.entry_count());
auto reg_entry = MUST(reg.entry(0));
auto hart_id_or_error = reg_entry.bus_address().as_flatptr();
if (hart_id_or_error.is_error())
PANIC("RISC-V CPU node {} has invalid reg property: {:hex-dump}", cpu_name, reg_entry.bus_address().raw());
auto hart_id = hart_id_or_error.release_value();
// FIXME: Use the correct hart ID here once we support SMP on RISC-V.
if (hart_id != g_boot_info.arch_specific.boot_hart_id)
continue;
auto isa_extensions = cpu.get_property("riscv,isa-extensions"sv);
if (!isa_extensions.has_value()) {
dbgln("RISC-V CPU node {} doesn't have the \"riscv,isa-extensions\" property, don't know what extensions are supported", cpu_name);
m_features = CPUFeature::Type(0);
break;
}
m_features = isa_extensions_property_to_cpu_features(isa_extensions.value());
m_info->build_isa_string(*this);
dmesgln("CPU[{}]: ISA: {}", id(), m_info->isa_string());
// Enable the floating-point unit and vector extension.
auto sstatus = RISCV64::CSR::SSTATUS::read();
sstatus.FS = RISCV64::CSR::SSTATUS::FloatingPointStatus::Initial;
if (has_feature(CPUFeature::V))
sstatus.VS = RISCV64::CSR::SSTATUS::VectorStatus::Initial;
RISCV64::CSR::SSTATUS::write(sstatus);
if (has_feature(CPUFeature::V)) {
auto vlenb = RISCV64::CSR::read<RISCV64::CSR::Address::VLENB>();
if (vlenb > MAX_SUPPORTED_VLENB)
PANIC("Unsupported vector register size: {} bits", vlenb * 8);
dmesgln("CPU[{}]: VLEN={}", id(), vlenb * 8);
}
store_fpu_state(&s_clean_fpu_state);
generate_userspace_extension_bitmask();
break;
}
}
void Processor::generate_userspace_extension_bitmask()
{
#define __ENUMERATE_RISCV_EXTENSION_BITMASK_BIT(feature_name, group_id, bit_position) \
if (has_feature(CPUFeature::feature_name)) \
m_userspace_extension_bitmask[group_id] |= 1zu << bit_position;
ENUMERATE_RISCV_EXTENSION_BITMASK_BITS(__ENUMERATE_RISCV_EXTENSION_BITMASK_BIT)
#undef __ENUMERATE_RISCV_EXTENSION
}
}
#include <Kernel/Arch/ProcessorFunctions.include>