opensbi/lib/sbi_hart.c

318 lines
7.0 KiB
C

/*
* Copyright (c) 2018 Western Digital Corporation or its affiliates.
*
* Authors:
* Anup Patel <anup.patel@wdc.com>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <sbi/riscv_asm.h>
#include <sbi/riscv_barrier.h>
#include <sbi/riscv_encoding.h>
#include <sbi/riscv_locks.h>
#include <sbi/sbi_bits.h>
#include <sbi/sbi_console.h>
#include <sbi/sbi_error.h>
#include <sbi/sbi_hart.h>
#include <sbi/sbi_platform.h>
static void mstatus_init(struct sbi_scratch *scratch, u32 hartid)
{
struct sbi_platform *plat = sbi_platform_ptr(scratch);
/* Enable FPU */
if (misa_extension('D') || misa_extension('F'))
csr_write(mstatus, MSTATUS_FS);
/* Enable user/supervisor use of perf counters */
if (misa_extension('S') &&
sbi_platform_has_scounteren(plat))
csr_write(scounteren, -1);
if (sbi_platform_has_mcounteren(plat))
csr_write(mcounteren, -1);
/* Disable all interrupts */
csr_write(mie, 0);
/* Disable S-mode paging */
if (misa_extension('S'))
csr_write(sptbr, 0);
}
#ifdef __riscv_flen
static void init_fp_reg(int i)
{
/* TODO: */
}
#endif
static int fp_init(u32 hartid)
{
#ifdef __riscv_flen
int i;
#else
unsigned long fd_mask;
#endif
if (!misa_extension('D') && !misa_extension('F'))
return 0;
if (!(csr_read(mstatus) & MSTATUS_FS))
return SBI_EINVAL;
#ifdef __riscv_flen
for (i = 0; i < 32; i++)
init_fp_reg(i);
csr_write(fcsr, 0);
#else
fd_mask = (1 << ('F' - 'A')) | (1 << ('D' - 'A'));
csr_clear(misa, fd_mask);
if (csr_read(misa) & fd_mask)
return SBI_ENOTSUPP;
#endif
return 0;
}
static int delegate_traps(u32 hartid)
{
/* send S-mode interrupts and most exceptions straight to S-mode */
unsigned long interrupts = MIP_SSIP | MIP_STIP | MIP_SEIP;
unsigned long exceptions = (1U << CAUSE_MISALIGNED_FETCH) |
(1U << CAUSE_FETCH_PAGE_FAULT) |
(1U << CAUSE_BREAKPOINT) |
(1U << CAUSE_LOAD_PAGE_FAULT) |
(1U << CAUSE_STORE_PAGE_FAULT) |
(1U << CAUSE_USER_ECALL);
if (!misa_extension('S'))
return 0;
csr_write(mideleg, interrupts);
csr_write(medeleg, exceptions);
if (csr_read(mideleg) != interrupts)
return SBI_EFAIL;
if (csr_read(medeleg) != exceptions)
return SBI_EFAIL;
return 0;
}
unsigned long log2roundup(unsigned long x)
{
unsigned long ret = 0;
while (ret < __riscv_xlen) {
if (x <= (1UL << ret))
break;
ret++;
}
return ret;
}
void sbi_hart_pmp_dump(struct sbi_scratch *scratch)
{
struct sbi_platform *plat = sbi_platform_ptr(scratch);
unsigned long prot, addr, size, l2l;
unsigned int i;
if (!sbi_platform_has_pmp(plat))
return;
for (i = 0; i < PMP_COUNT; i++) {
pmp_get(i, &prot, &addr, &l2l);
if (!(prot & PMP_A))
continue;
if (l2l < __riscv_xlen)
size = (1UL << l2l);
else
size = 0;
#if __riscv_xlen == 32
sbi_printf("PMP%d: 0x%08lx-0x%08lx (A",
#else
sbi_printf("PMP%d: 0x%016lx-0x%016lx (A",
#endif
i, addr, addr + size - 1);
if (prot & PMP_L)
sbi_printf(",L");
if (prot & PMP_R)
sbi_printf(",R");
if (prot & PMP_W)
sbi_printf(",W");
if (prot & PMP_X)
sbi_printf(",X");
sbi_printf(")\n");
}
}
static int pmp_init(struct sbi_scratch *scratch, u32 hartid)
{
u32 i, count;
unsigned long fw_start, fw_size_log2;
ulong prot, addr, log2size;
struct sbi_platform *plat = sbi_platform_ptr(scratch);
if (!sbi_platform_has_pmp(plat))
return 0;
fw_size_log2 = log2roundup(scratch->fw_size);
fw_start = scratch->fw_start & ~((1UL << fw_size_log2) - 1UL);
pmp_set(0, 0, fw_start, fw_size_log2);
count = sbi_platform_pmp_region_count(plat, hartid);
if ((PMP_COUNT - 1) < count)
count = (PMP_COUNT - 1);
for (i = 0; i < count; i++) {
if (sbi_platform_pmp_region_info(plat, hartid, i,
&prot, &addr, &log2size))
continue;
pmp_set(i + 1, prot, addr, log2size);
}
return 0;
}
int sbi_hart_init(struct sbi_scratch *scratch, u32 hartid)
{
int rc;
mstatus_init(scratch, hartid);
rc = fp_init(hartid);
if (rc)
return rc;
rc = delegate_traps(hartid);
if (rc)
return rc;
return pmp_init(scratch, hartid);
}
void __attribute__((noreturn)) sbi_hart_hang(void)
{
while (1)
wfi();
__builtin_unreachable();
}
void __attribute__((noreturn)) sbi_hart_boot_next(unsigned long arg0,
unsigned long arg1,
unsigned long next_addr,
unsigned long next_mode)
{
unsigned long val;
if (next_mode != PRV_S && next_mode != PRV_M && next_mode != PRV_U)
sbi_hart_hang();
if (next_mode == PRV_S && !misa_extension('S'))
sbi_hart_hang();
if (next_mode == PRV_U && !misa_extension('U'))
sbi_hart_hang();
val = csr_read(mstatus);
val = INSERT_FIELD(val, MSTATUS_MPP, next_mode);
val = INSERT_FIELD(val, MSTATUS_MPIE, 0);
csr_write(mstatus, val);
csr_write(mepc, next_addr);
if (next_mode == PRV_S) {
csr_write(stvec, next_addr);
csr_write(sscratch, 0);
csr_write(sie, 0);
csr_write(satp, 0);
} else if (next_mode == PRV_U) {
csr_write(utvec, next_addr);
csr_write(uscratch, 0);
csr_write(uie, 0);
}
register unsigned long a0 asm ("a0") = arg0;
register unsigned long a1 asm ("a1") = arg1;
__asm__ __volatile__ ("mret" : : "r" (a0), "r" (a1));
__builtin_unreachable();
}
static spinlock_t avail_hart_mask_lock = SPIN_LOCK_INITIALIZER;
static volatile unsigned long avail_hart_mask = 0;
void sbi_hart_mark_available(u32 hartid)
{
spin_lock(&avail_hart_mask_lock);
avail_hart_mask |= (1UL << hartid);
spin_unlock(&avail_hart_mask_lock);
}
void sbi_hart_unmark_available(u32 hartid)
{
spin_lock(&avail_hart_mask_lock);
avail_hart_mask &= ~(1UL << hartid);
spin_unlock(&avail_hart_mask_lock);
}
ulong sbi_hart_available_mask(void)
{
ulong ret;
spin_lock(&avail_hart_mask_lock);
ret = avail_hart_mask;
spin_unlock(&avail_hart_mask_lock);
return ret;
}
typedef struct sbi_scratch *(*h2s)(ulong hartid);
struct sbi_scratch *sbi_hart_id_to_scratch(struct sbi_scratch *scratch,
u32 hartid)
{
return ((h2s)scratch->hartid_to_scratch)(hartid);
}
#define COLDBOOT_WAIT_BITMAP_SIZE __riscv_xlen
static spinlock_t coldboot_wait_bitmap_lock = SPIN_LOCK_INITIALIZER;
static unsigned long coldboot_wait_bitmap = 0;
void sbi_hart_wait_for_coldboot(struct sbi_scratch *scratch, u32 hartid)
{
unsigned long mipval;
struct sbi_platform *plat = sbi_platform_ptr(scratch);
if ((sbi_platform_hart_count(plat) <= hartid) ||
(COLDBOOT_WAIT_BITMAP_SIZE <= hartid))
sbi_hart_hang();
do {
spin_lock(&coldboot_wait_bitmap_lock);
coldboot_wait_bitmap |= (1UL << hartid);
spin_unlock(&coldboot_wait_bitmap_lock);
wfi();
mipval = csr_read(mip);
spin_lock(&coldboot_wait_bitmap_lock);
coldboot_wait_bitmap &= ~(1UL << hartid);
spin_unlock(&coldboot_wait_bitmap_lock);
} while (!(mipval && MIP_MSIP));
csr_clear(mip, MIP_MSIP);
}
void sbi_hart_wake_coldboot_harts(struct sbi_scratch *scratch, u32 hartid)
{
struct sbi_platform *plat = sbi_platform_ptr(scratch);
int max_hart = sbi_platform_hart_count(plat);
for(int i = 0; i < max_hart ; i++) {
/* send an IPI to every other hart */
spin_lock(&coldboot_wait_bitmap_lock);
if ((i != hartid) && (coldboot_wait_bitmap & (1UL << i)))
sbi_platform_ipi_inject(plat, i, hartid);
spin_unlock(&coldboot_wait_bitmap_lock);
}
}