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#include "mtrap.h"
#include "atomic.h"
#include "vm.h"
#include "fp_emulation.h"
#include <string.h>
pte_t* root_page_table;
uintptr_t first_free_paddr;
uintptr_t mem_size;
uintptr_t num_harts;
static void mstatus_init()
{
uintptr_t ms = 0;
ms = INSERT_FIELD(ms, MSTATUS_VM, VM_CHOICE);
ms = INSERT_FIELD(ms, MSTATUS_FS, 1);
write_csr(mstatus, ms);
ms = read_csr(mstatus);
assert(EXTRACT_FIELD(ms, MSTATUS_VM) == VM_CHOICE);
write_csr(mtimecmp, 0);
clear_csr(mip, MIP_MSIP);
write_csr(mie, -1);
write_csr(mucounteren, -1);
write_csr(mscounteren, -1);
}
static void delegate_traps()
{
uintptr_t interrupts = MIP_SSIP | MIP_STIP;
uintptr_t exceptions =
(1U << CAUSE_MISALIGNED_FETCH) |
(1U << CAUSE_FAULT_FETCH) |
(1U << CAUSE_BREAKPOINT) |
(1U << CAUSE_FAULT_LOAD) |
(1U << CAUSE_FAULT_STORE) |
(1U << CAUSE_BREAKPOINT) |
(1U << CAUSE_USER_ECALL);
write_csr(mideleg, interrupts);
write_csr(medeleg, exceptions);
assert(read_csr(mideleg) == interrupts);
assert(read_csr(medeleg) == exceptions);
}
static void fp_init()
{
assert(read_csr(mstatus) & MSTATUS_FS);
#ifdef __riscv_hard_float
if (!supports_extension('D'))
die("FPU not found; recompile pk with -msoft-float");
for (int i = 0; i < 32; i++)
init_fp_reg(i);
write_csr(fcsr, 0);
#else
if (supports_extension('D'))
die("FPU unexpectedly found; recompile with -mhard-float");
#endif
}
void hls_init(uintptr_t id, csr_t* csrs)
{
hls_t* hls = OTHER_HLS(id);
memset(hls, 0, sizeof(*hls));
hls->csrs = csrs;
}
static uintptr_t sbi_top_paddr()
{
extern char _end;
return ROUNDUP((uintptr_t)&_end, RISCV_PGSIZE);
}
static void memory_init()
{
mem_size = mem_size / MEGAPAGE_SIZE * MEGAPAGE_SIZE;
first_free_paddr = sbi_top_paddr() + num_harts * RISCV_PGSIZE;
}
static void hart_init()
{
mstatus_init();
fp_init();
delegate_traps();
}
void init_first_hart()
{
hart_init();
memset(HLS(), 0, sizeof(*HLS()));
parse_config_string();
memory_init();
boot_loader();
}
void init_other_hart()
{
hart_init();
// wait until hart 0 discovers us
while (*(csr_t * volatile *)&HLS()->csrs == NULL)
;
boot_other_hart();
}
void enter_supervisor_mode(void (*fn)(uintptr_t), uintptr_t stack)
{
uintptr_t mstatus = read_csr(mstatus);
mstatus = INSERT_FIELD(mstatus, MSTATUS_MPP, PRV_S);
mstatus = INSERT_FIELD(mstatus, MSTATUS_MPIE, 0);
write_csr(mstatus, mstatus);
write_csr(mscratch, MACHINE_STACK_TOP() - MENTRY_FRAME_SIZE);
write_csr(mepc, fn);
write_csr(sptbr, (uintptr_t)root_page_table >> RISCV_PGSHIFT);
asm volatile ("mv a0, %0; mv sp, %0; eret" : : "r" (stack));
__builtin_unreachable();
}
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