acrn-hypervisor/hypervisor/arch/x86/trampoline.c
Yin Fengwei 69dc939243 hv: drop the temperory stack for AP startup
By switching AP wakeup from broadcast to one by one, we could
set correct stack for each AP and drop the temp stack used during
AP boot.

Tracked-On: #2034
Signed-off-by: Yin Fengwei <fengwei.yin@intel.com>
Acked-by: Anthony Xu <anthony.xu@intel.com>
2018-12-17 19:16:43 +08:00

127 lines
3.5 KiB
C

/*
* Copyright (C) 2018 Intel Corporation. All rights reserved.
*
* SPDX-License-Identifier: BSD-3-Clause
*/
#include <hypervisor.h>
#include <reloc.h>
#include <trampoline.h>
#include <vm0_boot.h>
#include <e820.h>
uint64_t trampoline_start16_paddr;
/*
* Because trampoline code is relocated in different way, if HV code
* accesses trampoline using relative addressing, it needs to take
* out the HV relocation delta
*
* This function is valid if:
* - The hpa of HV code is always higher than trampoline code
* - The HV code is always relocated to higher address, compared
* with CONFIG_HV_RAM_START
*/
static uint64_t trampoline_relo_addr(const void *addr)
{
return (uint64_t)addr - get_hv_image_delta();
}
uint64_t read_trampoline_sym(const void *sym)
{
uint64_t *hva = (uint64_t *)(hpa2hva(trampoline_start16_paddr) + trampoline_relo_addr(sym));
return *hva;
}
void write_trampoline_sym(const void *sym, uint64_t val)
{
uint64_t *hva = (uint64_t *)(hpa2hva(trampoline_start16_paddr) + trampoline_relo_addr(sym));
*hva = val;
clflush(hva);
}
void write_trampoline_stack_sym(uint16_t pcpu_id)
{
uint64_t *hva, stack_sym_addr;
hva = (uint64_t *)(hpa2hva(trampoline_start16_paddr) + trampoline_relo_addr(secondary_cpu_stack));
stack_sym_addr = (uint64_t)&per_cpu(stack, pcpu_id)[CONFIG_STACK_SIZE - 1];
*hva = stack_sym_addr + get_hv_image_delta();
clflush(hva);
}
static void update_trampoline_code_refs(uint64_t dest_pa)
{
void *ptr;
uint64_t val;
int32_t i;
/*
* calculate the fixup CS:IP according to fixup target address
* dynamically.
*
* trampoline code starts in real mode,
* so the target addres is HPA
*/
val = dest_pa + trampoline_relo_addr(&trampoline_fixup_target);
ptr = hpa2hva(dest_pa + trampoline_relo_addr(&trampoline_fixup_cs));
*(uint16_t *)(ptr) = (uint16_t)((val >> 4U) & 0xFFFFU);
ptr = hpa2hva(dest_pa + trampoline_relo_addr(&trampoline_fixup_ip));
*(uint16_t *)(ptr) = (uint16_t)(val & 0xfU);
/* Update temporary page tables */
ptr = hpa2hva(dest_pa + trampoline_relo_addr(&cpu_boot_page_tables_ptr));
*(uint32_t *)(ptr) += (uint32_t)dest_pa;
ptr = hpa2hva(dest_pa + trampoline_relo_addr(&cpu_boot_page_tables_start));
*(uint64_t *)(ptr) += dest_pa;
ptr = hpa2hva(dest_pa + trampoline_relo_addr(&trampoline_pdpt_addr));
for (i = 0; i < 4; i++) {
*(uint64_t *)(ptr + sizeof(uint64_t) * i) += dest_pa;
}
/* update the gdt base pointer with relocated offset */
ptr = hpa2hva(dest_pa + trampoline_relo_addr(&trampoline_gdt_ptr));
*(uint64_t *)(ptr + 2) += dest_pa;
/* update trampoline jump pointer with relocated offset */
ptr = hpa2hva(dest_pa + trampoline_relo_addr(&trampoline_start64_fixup));
*(uint32_t *)ptr += (uint32_t)dest_pa;
/* update trampoline's main entry pointer */
ptr = hpa2hva(dest_pa + trampoline_relo_addr(main_entry));
*(uint64_t *)ptr += get_hv_image_delta();
}
uint64_t prepare_trampoline(void)
{
uint64_t size, dest_pa, i;
size = (uint64_t)(&ld_trampoline_end - &ld_trampoline_start);
#ifndef CONFIG_EFI_STUB
dest_pa = e820_alloc_low_memory(CONFIG_LOW_RAM_SIZE);
#else
dest_pa = (uint64_t)get_ap_trampoline_buf();
#endif
pr_dbg("trampoline code: %llx size %x", dest_pa, size);
/* Copy segment for AP initialization code below 1MB */
stac();
(void)memcpy_s(hpa2hva(dest_pa), (size_t)size, &ld_trampoline_load,
(size_t)size);
update_trampoline_code_refs(dest_pa);
for (i = 0UL; i < size; i = i + CACHE_LINE_SIZE) {
clflush(hpa2hva(dest_pa + i));
}
clac();
trampoline_start16_paddr = dest_pa;
return dest_pa;
}