Files
opensbi/lib/sbi/sbi_init.c
Atish Patra b677a9b8d6 lib: Implement hart hotplug
This patch adds support for hart hotplug in OpenSBI using a generic WFI
based approach. Hart hotplug can be achieved via SBI HSM extension which
allows supervisor mode software to start or stop any harts anytime.

Any platform wishes to implement platform specific hart hotplug must
implement both hart_start and hart_stop in addition to enable platform
feature SBI_PLATFORM_HAS_HART_HOTPLUG.

Signed-off-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
2020-02-24 18:07:55 +05:30

276 lines
6.6 KiB
C

/*
* SPDX-License-Identifier: BSD-2-Clause
*
* Copyright (c) 2019 Western Digital Corporation or its affiliates.
*
* Authors:
* Anup Patel <anup.patel@wdc.com>
*/
#include <sbi/riscv_asm.h>
#include <sbi/riscv_atomic.h>
#include <sbi/sbi_console.h>
#include <sbi/sbi_ecall.h>
#include <sbi/sbi_hart.h>
#include <sbi/sbi_hsm.h>
#include <sbi/sbi_ipi.h>
#include <sbi/sbi_platform.h>
#include <sbi/sbi_system.h>
#include <sbi/sbi_timer.h>
#include <sbi/sbi_tlb.h>
#include <sbi/sbi_version.h>
#define BANNER \
" ____ _____ ____ _____\n" \
" / __ \\ / ____| _ \\_ _|\n" \
" | | | |_ __ ___ _ __ | (___ | |_) || |\n" \
" | | | | '_ \\ / _ \\ '_ \\ \\___ \\| _ < | |\n" \
" | |__| | |_) | __/ | | |____) | |_) || |_\n" \
" \\____/| .__/ \\___|_| |_|_____/|____/_____|\n" \
" | |\n" \
" |_|\n\n"
static void sbi_boot_prints(struct sbi_scratch *scratch, u32 hartid)
{
int xlen;
char str[64];
const struct sbi_platform *plat = sbi_platform_ptr(scratch);
#ifdef OPENSBI_VERSION_GIT
sbi_printf("\nOpenSBI %s\n", OPENSBI_VERSION_GIT);
#else
sbi_printf("\nOpenSBI v%d.%d\n", OPENSBI_VERSION_MAJOR,
OPENSBI_VERSION_MINOR);
#endif
sbi_printf(BANNER);
/* Determine MISA XLEN and MISA string */
xlen = misa_xlen();
if (xlen < 1) {
sbi_printf("Error %d getting MISA XLEN\n", xlen);
sbi_hart_hang();
}
xlen = 16 * (1 << xlen);
misa_string(str, sizeof(str));
/* Platform details */
sbi_printf("Platform Name : %s\n", sbi_platform_name(plat));
sbi_printf("Platform HART Features : RV%d%s\n", xlen, str);
sbi_printf("Platform Max HARTs : %d\n",
sbi_platform_hart_count(plat));
sbi_printf("Current Hart : %u\n", hartid);
/* Firmware details */
sbi_printf("Firmware Base : 0x%lx\n", scratch->fw_start);
sbi_printf("Firmware Size : %d KB\n",
(u32)(scratch->fw_size / 1024));
/* Generic details */
sbi_printf("Runtime SBI Version : %d.%d\n",
sbi_ecall_version_major(), sbi_ecall_version_minor());
sbi_printf("\n");
sbi_hart_delegation_dump(scratch);
sbi_hart_pmp_dump(scratch);
}
static unsigned long init_count_offset;
static void __noreturn init_coldboot(struct sbi_scratch *scratch, u32 hartid)
{
int rc;
unsigned long *init_count;
const struct sbi_platform *plat = sbi_platform_ptr(scratch);
init_count_offset = sbi_scratch_alloc_offset(__SIZEOF_POINTER__,
"INIT_COUNT");
if (!init_count_offset)
sbi_hart_hang();
rc = sbi_hsm_init(scratch, hartid, TRUE);
if (rc)
sbi_hart_hang();
rc = sbi_system_early_init(scratch, TRUE);
if (rc)
sbi_hart_hang();
rc = sbi_hart_init(scratch, hartid, TRUE);
if (rc)
sbi_hart_hang();
rc = sbi_console_init(scratch);
if (rc)
sbi_hart_hang();
rc = sbi_platform_irqchip_init(plat, TRUE);
if (rc)
sbi_hart_hang();
rc = sbi_ipi_init(scratch, TRUE);
if (rc)
sbi_hart_hang();
rc = sbi_tlb_init(scratch, TRUE);
if (rc)
sbi_hart_hang();
rc = sbi_timer_init(scratch, TRUE);
if (rc)
sbi_hart_hang();
rc = sbi_ecall_init();
if (rc)
sbi_hart_hang();
rc = sbi_system_final_init(scratch, TRUE);
if (rc)
sbi_hart_hang();
if (!(scratch->options & SBI_SCRATCH_NO_BOOT_PRINTS))
sbi_boot_prints(scratch, hartid);
sbi_hart_wake_coldboot_harts(scratch, hartid);
sbi_hart_mark_available(hartid);
init_count = sbi_scratch_offset_ptr(scratch, init_count_offset);
(*init_count)++;
sbi_hsm_prepare_next_jump(scratch, hartid);
sbi_hart_switch_mode(hartid, scratch->next_arg1, scratch->next_addr,
scratch->next_mode, FALSE);
}
static void __noreturn init_warmboot(struct sbi_scratch *scratch, u32 hartid)
{
int rc;
unsigned long *init_count;
const struct sbi_platform *plat = sbi_platform_ptr(scratch);
sbi_hart_wait_for_coldboot(scratch, hartid);
if (!init_count_offset)
sbi_hart_hang();
rc = sbi_hsm_init(scratch, hartid, FALSE);
if (rc)
sbi_hart_hang();
rc = sbi_system_early_init(scratch, FALSE);
if (rc)
sbi_hart_hang();
rc = sbi_hart_init(scratch, hartid, FALSE);
if (rc)
sbi_hart_hang();
rc = sbi_platform_irqchip_init(plat, FALSE);
if (rc)
sbi_hart_hang();
rc = sbi_ipi_init(scratch, FALSE);
if (rc)
sbi_hart_hang();
rc = sbi_tlb_init(scratch, FALSE);
if (rc)
sbi_hart_hang();
rc = sbi_timer_init(scratch, FALSE);
if (rc)
sbi_hart_hang();
rc = sbi_system_final_init(scratch, FALSE);
if (rc)
sbi_hart_hang();
sbi_hart_mark_available(hartid);
init_count = sbi_scratch_offset_ptr(scratch, init_count_offset);
(*init_count)++;
sbi_hsm_prepare_next_jump(scratch, hartid);
sbi_hart_switch_mode(hartid, scratch->next_arg1,
scratch->next_addr,
scratch->next_mode, FALSE);
}
static atomic_t coldboot_lottery = ATOMIC_INITIALIZER(0);
/**
* Initialize OpenSBI library for current HART and jump to next
* booting stage.
*
* The function expects following:
* 1. The 'mscratch' CSR is pointing to sbi_scratch of current HART
* 2. Stack pointer (SP) is setup for current HART
* 3. Interrupts are disabled in MSTATUS CSR
* 4. All interrupts are disabled in MIE CSR
*
* @param scratch pointer to sbi_scratch of current HART
*/
void __noreturn sbi_init(struct sbi_scratch *scratch)
{
bool coldboot = FALSE;
u32 hartid = sbi_current_hartid();
const struct sbi_platform *plat = sbi_platform_ptr(scratch);
if (sbi_platform_hart_disabled(plat, hartid))
sbi_hart_hang();
if (atomic_add_return(&coldboot_lottery, 1) == 1)
coldboot = TRUE;
if (coldboot)
init_coldboot(scratch, hartid);
else
init_warmboot(scratch, hartid);
}
unsigned long sbi_init_count(u32 hartid)
{
struct sbi_scratch *scratch;
unsigned long *init_count;
if (sbi_platform_hart_count(sbi_platform_thishart_ptr()) <= hartid ||
!init_count_offset)
return 0;
scratch = sbi_hart_id_to_scratch(sbi_scratch_thishart_ptr(), hartid);
init_count = sbi_scratch_offset_ptr(scratch, init_count_offset);
return *init_count;
}
/**
* Exit OpenSBI library for current HART and stop HART
*
* The function expects following:
* 1. The 'mscratch' CSR is pointing to sbi_scratch of current HART
* 2. Stack pointer (SP) is setup for current HART
*
* @param scratch pointer to sbi_scratch of current HART
*/
void __noreturn sbi_exit(struct sbi_scratch *scratch)
{
u32 hartid = sbi_current_hartid();
const struct sbi_platform *plat = sbi_platform_ptr(scratch);
if (sbi_platform_hart_disabled(plat, hartid))
sbi_hart_hang();
sbi_hart_unmark_available(hartid);
sbi_platform_early_exit(plat);
sbi_timer_exit(scratch);
sbi_ipi_exit(scratch);
sbi_platform_irqchip_exit(plat);
sbi_platform_final_exit(plat);
sbi_hsm_exit(scratch);
}