mirror of
https://github.com/AsahiLinux/u-boot
synced 2024-11-26 22:52:18 +00:00
8b2eb776b1
With new SMP-enabled CPUs with ARC HS38 cores and corresponding support in Linux kernel it's required to add basic SMP support in U-Boot. Currently we assume the one and only core starts execution after power-on. So most of things in U-Boot is handled in UP mode. But when U-Boot is used for loading and starting Linux kernel right before jumping to kernel's entry point U-Boot: [1] Sets all slave cores to jump to the same address [kernel's entry point] [2] Really starts all slav cores In ARC's implemetation of SMP in Linux kernel all cores are supposed to run the same start-up code. But only core with ID 0 (master core) processes further while others are looping waiting for master core to complete some initialization. That means it's safe to un-pause slave cores and let them execute kernel - they will wait for master anyway. Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com> Cc: Vineet Gupta <vgupta@synopsys.com>
112 lines
2.4 KiB
C
112 lines
2.4 KiB
C
/*
|
|
* Copyright (C) 2013-2014 Synopsys, Inc. All rights reserved.
|
|
*
|
|
* SPDX-License-Identifier: GPL-2.0+
|
|
*/
|
|
|
|
#include <common.h>
|
|
|
|
DECLARE_GLOBAL_DATA_PTR;
|
|
|
|
static ulong get_sp(void)
|
|
{
|
|
ulong ret;
|
|
|
|
asm("mov %0, sp" : "=r"(ret) : );
|
|
return ret;
|
|
}
|
|
|
|
void arch_lmb_reserve(struct lmb *lmb)
|
|
{
|
|
ulong sp;
|
|
|
|
/*
|
|
* Booting a (Linux) kernel image
|
|
*
|
|
* Allocate space for command line and board info - the
|
|
* address should be as high as possible within the reach of
|
|
* the kernel (see CONFIG_SYS_BOOTMAPSZ settings), but in unused
|
|
* memory, which means far enough below the current stack
|
|
* pointer.
|
|
*/
|
|
sp = get_sp();
|
|
debug("## Current stack ends at 0x%08lx ", sp);
|
|
|
|
/* adjust sp by 4K to be safe */
|
|
sp -= 4096;
|
|
lmb_reserve(lmb, sp, (CONFIG_SYS_SDRAM_BASE + gd->ram_size - sp));
|
|
}
|
|
|
|
static int cleanup_before_linux(void)
|
|
{
|
|
disable_interrupts();
|
|
flush_dcache_all();
|
|
invalidate_icache_all();
|
|
|
|
return 0;
|
|
}
|
|
|
|
/* Subcommand: PREP */
|
|
static void boot_prep_linux(bootm_headers_t *images)
|
|
{
|
|
if (image_setup_linux(images))
|
|
hang();
|
|
}
|
|
|
|
__weak void smp_set_core_boot_addr(unsigned long addr, int corenr) {}
|
|
__weak void smp_kick_all_cpus(void) {}
|
|
|
|
/* Subcommand: GO */
|
|
static void boot_jump_linux(bootm_headers_t *images, int flag)
|
|
{
|
|
void (*kernel_entry)(int zero, int arch, uint params);
|
|
unsigned int r0, r2;
|
|
int fake = (flag & BOOTM_STATE_OS_FAKE_GO);
|
|
|
|
kernel_entry = (void (*)(int, int, uint))images->ep;
|
|
|
|
debug("## Transferring control to Linux (at address %08lx)...\n",
|
|
(ulong) kernel_entry);
|
|
bootstage_mark(BOOTSTAGE_ID_RUN_OS);
|
|
|
|
printf("\nStarting kernel ...%s\n\n", fake ?
|
|
"(fake run for tracing)" : "");
|
|
bootstage_mark_name(BOOTSTAGE_ID_BOOTM_HANDOFF, "start_kernel");
|
|
|
|
cleanup_before_linux();
|
|
|
|
if (IMAGE_ENABLE_OF_LIBFDT && images->ft_len) {
|
|
r0 = 2;
|
|
r2 = (unsigned int)images->ft_addr;
|
|
} else {
|
|
r0 = 1;
|
|
r2 = (unsigned int)getenv("bootargs");
|
|
}
|
|
|
|
smp_set_core_boot_addr((unsigned long)kernel_entry, -1);
|
|
smp_kick_all_cpus();
|
|
|
|
if (!fake)
|
|
kernel_entry(r0, 0, r2);
|
|
}
|
|
|
|
int do_bootm_linux(int flag, int argc, char *argv[], bootm_headers_t *images)
|
|
{
|
|
/* No need for those on ARC */
|
|
if ((flag & BOOTM_STATE_OS_BD_T) || (flag & BOOTM_STATE_OS_CMDLINE))
|
|
return -1;
|
|
|
|
if (flag & BOOTM_STATE_OS_PREP) {
|
|
boot_prep_linux(images);
|
|
return 0;
|
|
}
|
|
|
|
if (flag & (BOOTM_STATE_OS_GO | BOOTM_STATE_OS_FAKE_GO)) {
|
|
boot_jump_linux(images, flag);
|
|
return 0;
|
|
}
|
|
|
|
boot_prep_linux(images);
|
|
boot_jump_linux(images, flag);
|
|
return 0;
|
|
}
|