u-boot/lib/efi/efi_stub.c
Heinrich Schuchardt dec88e41e0 efi_loader: consistent naming of protocol GUIDs
We should consistently use the same name for protocol GUIDs as defined in
the UEFI specification. Not adhering to this rule has led to duplicate
definitions for the EFI_LOADED_IMAGE_PROTOCOL_GUID.

Adjust misnamed protocol GUIDs.

Adjust the text for the graphics output protocol in the output of the
`efidebug dh` command.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2019-04-23 00:37:27 +02:00

390 lines
9.5 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright (c) 2015 Google, Inc
*
* EFI information obtained here:
* http://wiki.phoenix.com/wiki/index.php/EFI_BOOT_SERVICES
*
* Loads a payload (U-Boot) within the EFI environment. This is built as an
* EFI application. It can be built either in 32-bit or 64-bit mode.
*/
#include <common.h>
#include <debug_uart.h>
#include <efi.h>
#include <efi_api.h>
#include <errno.h>
#include <ns16550.h>
#include <asm/cpu.h>
#include <asm/io.h>
#include <linux/err.h>
#include <linux/types.h>
#ifndef CONFIG_X86
/*
* Problem areas:
* - putc() uses the ns16550 address directly and assumed I/O access. Many
* platforms will use memory access
* get_codeseg32() is only meaningful on x86
*/
#error "This file needs to be ported for use on architectures"
#endif
static struct efi_priv *global_priv;
static bool use_uart;
struct __packed desctab_info {
uint16_t limit;
uint64_t addr;
uint16_t pad;
};
/*
* EFI uses Unicode and we don't. The easiest way to get a sensible output
* function is to use the U-Boot debug UART. We use EFI's console output
* function where available, and assume the built-in UART after that. We rely
* on EFI to set up the UART for us and just bring in the functions here.
* This last bit is a bit icky, but it's only for debugging anyway. We could
* build in ns16550.c with some effort, but this is a payload loader after
* all.
*
* Note: We avoid using printf() so we don't need to bring in lib/vsprintf.c.
* That would require some refactoring since we already build this for U-Boot.
* Building an EFI shared library version would have to be a separate stem.
* That might push us to using the SPL framework to build this stub. However
* that would involve a round of EFI-specific changes in SPL. Worth
* considering if we start needing more U-Boot functionality. Note that we
* could then move get_codeseg32() to arch/x86/cpu/cpu.c.
*/
void _debug_uart_init(void)
{
}
void putc(const char ch)
{
if (ch == '\n')
putc('\r');
if (use_uart) {
NS16550_t com_port = (NS16550_t)0x3f8;
while ((inb((ulong)&com_port->lsr) & UART_LSR_THRE) == 0)
;
outb(ch, (ulong)&com_port->thr);
} else {
efi_putc(global_priv, ch);
}
}
void puts(const char *str)
{
while (*str)
putc(*str++);
}
static void _debug_uart_putc(int ch)
{
putc(ch);
}
DEBUG_UART_FUNCS
void *memcpy(void *dest, const void *src, size_t size)
{
unsigned char *dptr = dest;
const unsigned char *ptr = src;
const unsigned char *end = src + size;
while (ptr < end)
*dptr++ = *ptr++;
return dest;
}
void *memset(void *inptr, int ch, size_t size)
{
char *ptr = inptr;
char *end = ptr + size;
while (ptr < end)
*ptr++ = ch;
return ptr;
}
static void jump_to_uboot(ulong cs32, ulong addr, ulong info)
{
#ifdef CONFIG_EFI_STUB_32BIT
/*
* U-Boot requires these parameters in registers, not on the stack.
* See _x86boot_start() for this code.
*/
typedef void (*func_t)(int bist, int unused, ulong info)
__attribute__((regparm(3)));
((func_t)addr)(0, 0, info);
#else
cpu_call32(cs32, CONFIG_SYS_TEXT_BASE, info);
#endif
}
#ifdef CONFIG_EFI_STUB_64BIT
static void get_gdt(struct desctab_info *info)
{
asm volatile ("sgdt %0" : : "m"(*info) : "memory");
}
#endif
static inline unsigned long read_cr3(void)
{
unsigned long val;
asm volatile("mov %%cr3,%0" : "=r" (val) : : "memory");
return val;
}
/**
* get_codeseg32() - Find the code segment to use for 32-bit code
*
* U-Boot only works in 32-bit mode at present, so when booting from 64-bit
* EFI we must first change to 32-bit mode. To do this we need to find the
* correct code segment to use (an entry in the Global Descriptor Table).
*
* @return code segment GDT offset, or 0 for 32-bit EFI, -ENOENT if not found
*/
static int get_codeseg32(void)
{
int cs32 = 0;
#ifdef CONFIG_EFI_STUB_64BIT
struct desctab_info gdt;
uint64_t *ptr;
int i;
get_gdt(&gdt);
for (ptr = (uint64_t *)(unsigned long)gdt.addr, i = 0; i < gdt.limit;
i += 8, ptr++) {
uint64_t desc = *ptr;
uint64_t base, limit;
/*
* Check that the target U-Boot jump address is within the
* selector and that the selector is of the right type.
*/
base = ((desc >> GDT_BASE_LOW_SHIFT) & GDT_BASE_LOW_MASK) |
((desc >> GDT_BASE_HIGH_SHIFT) & GDT_BASE_HIGH_MASK)
<< 16;
limit = ((desc >> GDT_LIMIT_LOW_SHIFT) & GDT_LIMIT_LOW_MASK) |
((desc >> GDT_LIMIT_HIGH_SHIFT) & GDT_LIMIT_HIGH_MASK)
<< 16;
base <<= 12; /* 4KB granularity */
limit <<= 12;
if ((desc & GDT_PRESENT) && (desc & GDT_NOTSYS) &&
!(desc & GDT_LONG) && (desc & GDT_4KB) &&
(desc & GDT_32BIT) && (desc & GDT_CODE) &&
CONFIG_SYS_TEXT_BASE > base &&
CONFIG_SYS_TEXT_BASE + CONFIG_SYS_MONITOR_LEN < limit
) {
cs32 = i;
break;
}
}
#ifdef DEBUG
puts("\ngdt: ");
printhex8(gdt.limit);
puts(", addr: ");
printhex8(gdt.addr >> 32);
printhex8(gdt.addr);
for (i = 0; i < gdt.limit; i += 8) {
uint32_t *ptr = (uint32_t *)((unsigned long)gdt.addr + i);
puts("\n");
printhex2(i);
puts(": ");
printhex8(ptr[1]);
puts(" ");
printhex8(ptr[0]);
}
puts("\n ");
puts("32-bit code segment: ");
printhex2(cs32);
puts("\n ");
puts("page_table: ");
printhex8(read_cr3());
puts("\n ");
#endif
if (!cs32) {
puts("Can't find 32-bit code segment\n");
return -ENOENT;
}
#endif
return cs32;
}
static int setup_info_table(struct efi_priv *priv, int size)
{
struct efi_info_hdr *info;
efi_status_t ret;
/* Get some memory for our info table */
priv->info_size = size;
info = efi_malloc(priv, priv->info_size, &ret);
if (ret) {
printhex2(ret);
puts(" No memory for info table: ");
return ret;
}
memset(info, '\0', sizeof(*info));
info->version = EFI_TABLE_VERSION;
info->hdr_size = sizeof(*info);
priv->info = info;
priv->next_hdr = (char *)info + info->hdr_size;
return 0;
}
static void add_entry_addr(struct efi_priv *priv, enum efi_entry_t type,
void *ptr1, int size1, void *ptr2, int size2)
{
struct efi_entry_hdr *hdr = priv->next_hdr;
hdr->type = type;
hdr->size = size1 + size2;
hdr->addr = 0;
hdr->link = ALIGN(sizeof(*hdr) + hdr->size, 16);
priv->next_hdr += hdr->link;
memcpy(hdr + 1, ptr1, size1);
memcpy((void *)(hdr + 1) + size1, ptr2, size2);
priv->info->total_size = (ulong)priv->next_hdr - (ulong)priv->info;
}
/**
* efi_main() - Start an EFI image
*
* This function is called by our EFI start-up code. It handles running
* U-Boot. If it returns, EFI will continue.
*/
efi_status_t EFIAPI efi_main(efi_handle_t image,
struct efi_system_table *sys_table)
{
struct efi_priv local_priv, *priv = &local_priv;
struct efi_boot_services *boot = sys_table->boottime;
struct efi_mem_desc *desc;
struct efi_entry_memmap map;
struct efi_gop *gop;
struct efi_entry_gopmode mode;
struct efi_entry_systable table;
efi_guid_t efi_gop_guid = EFI_GRAPHICS_OUTPUT_PROTOCOL_GUID;
efi_uintn_t key, desc_size, size;
efi_status_t ret;
u32 version;
int cs32;
ret = efi_init(priv, "Payload", image, sys_table);
if (ret) {
printhex2(ret);
puts(" efi_init() failed\n");
return ret;
}
global_priv = priv;
cs32 = get_codeseg32();
if (cs32 < 0)
return EFI_UNSUPPORTED;
/* Get the memory map so we can switch off EFI */
size = 0;
ret = boot->get_memory_map(&size, NULL, &key, &desc_size, &version);
if (ret != EFI_BUFFER_TOO_SMALL) {
printhex2(EFI_BITS_PER_LONG);
putc(' ');
printhex2(ret);
puts(" No memory map\n");
return ret;
}
size += 1024; /* Since doing a malloc() may change the memory map! */
desc = efi_malloc(priv, size, &ret);
if (!desc) {
printhex2(ret);
puts(" No memory for memory descriptor\n");
return ret;
}
ret = setup_info_table(priv, size + 128);
if (ret)
return ret;
ret = boot->locate_protocol(&efi_gop_guid, NULL, (void **)&gop);
if (ret) {
puts(" GOP unavailable\n");
} else {
mode.fb_base = gop->mode->fb_base;
mode.fb_size = gop->mode->fb_size;
mode.info_size = gop->mode->info_size;
add_entry_addr(priv, EFIET_GOP_MODE, &mode, sizeof(mode),
gop->mode->info,
sizeof(struct efi_gop_mode_info));
}
ret = boot->get_memory_map(&size, desc, &key, &desc_size, &version);
if (ret) {
printhex2(ret);
puts(" Can't get memory map\n");
return ret;
}
table.sys_table = (ulong)sys_table;
add_entry_addr(priv, EFIET_SYS_TABLE, &table, sizeof(table), NULL, 0);
ret = boot->exit_boot_services(image, key);
if (ret) {
/*
* Unfortunately it happens that we cannot exit boot services
* the first time. But the second time it work. I don't know
* why but this seems to be a repeatable problem. To get
* around it, just try again.
*/
printhex2(ret);
puts(" Can't exit boot services\n");
size = sizeof(desc);
ret = boot->get_memory_map(&size, desc, &key, &desc_size,
&version);
if (ret) {
printhex2(ret);
puts(" Can't get memory map\n");
return ret;
}
ret = boot->exit_boot_services(image, key);
if (ret) {
printhex2(ret);
puts(" Can't exit boot services 2\n");
return ret;
}
}
/* The EFI UART won't work now, switch to a debug one */
use_uart = true;
map.version = version;
map.desc_size = desc_size;
add_entry_addr(priv, EFIET_MEMORY_MAP, &map, sizeof(map), desc, size);
add_entry_addr(priv, EFIET_END, NULL, 0, 0, 0);
memcpy((void *)CONFIG_SYS_TEXT_BASE, _binary_u_boot_bin_start,
(ulong)_binary_u_boot_bin_end -
(ulong)_binary_u_boot_bin_start);
#ifdef DEBUG
puts("EFI table at ");
printhex8((ulong)priv->info);
puts(" size ");
printhex8(priv->info->total_size);
#endif
putc('\n');
jump_to_uboot(cs32, CONFIG_SYS_TEXT_BASE, (ulong)priv->info);
return EFI_LOAD_ERROR;
}