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#include "bbl.h"
#include "mtrap.h"
#include "atomic.h"
#include "vm.h"
#include "bits.h"
#include "config.h"
#include "fdt.h"
#include <string.h>
extern char _payload_start, _payload_end; /* internal payload */
static const void* entry_point;
long disabled_hart_mask;
static uintptr_t dtb_output()
{
/*
* Place DTB after the payload, either the internal payload or a
* preloaded external payload specified in device-tree, if present.
*
* Note: linux kernel calls __va(dtb) to get the device-tree virtual
* address. The kernel's virtual mapping begins at its load address,
* thus mandating device-tree is in physical memory after the kernel.
*/
uintptr_t end = kernel_end ? (uintptr_t)kernel_end : (uintptr_t)&_payload_end;
return (end + MEGAPAGE_SIZE - 1) / MEGAPAGE_SIZE * MEGAPAGE_SIZE;
}
static void filter_dtb(uintptr_t source)
{
uintptr_t dest = dtb_output();
uint32_t size = fdt_size(source);
memcpy((void*)dest, (void*)source, size);
// Remove information from the chained FDT
filter_harts(dest, &disabled_hart_mask);
filter_plic(dest);
filter_compat(dest, "riscv,clint0");
filter_compat(dest, "riscv,debug-013");
}
void boot_other_hart(uintptr_t unused __attribute__((unused)))
{
const void* entry;
do {
entry = entry_point;
mb();
} while (!entry);
long hartid = read_csr(mhartid);
if ((1 << hartid) & disabled_hart_mask) {
while (1) {
__asm__ volatile("wfi");
#ifdef __riscv_div
__asm__ volatile("div x0, x0, x0");
#endif
}
}
enter_supervisor_mode(entry, hartid, dtb_output());
}
void boot_loader(uintptr_t dtb)
{
filter_dtb(dtb);
#ifdef PK_ENABLE_LOGO
print_logo();
#endif
#ifdef PK_PRINT_DEVICE_TREE
fdt_print(dtb_output());
#endif
mb();
/* Use optional FDT preloaded external payload if present */
entry_point = kernel_start ? kernel_start : &_payload_start;
boot_other_hart(0);
}
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