diff options
Diffstat (limited to 'lib/efi/efi_stub.c')
| -rw-r--r-- | lib/efi/efi_stub.c | 376 |
1 files changed, 0 insertions, 376 deletions
diff --git a/lib/efi/efi_stub.c b/lib/efi/efi_stub.c deleted file mode 100644 index a083c7f1e9b..00000000000 --- a/lib/efi/efi_stub.c +++ /dev/null @@ -1,376 +0,0 @@ -// 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 <debug_uart.h> -#include <efi.h> -#include <efi_api.h> -#include <errno.h> -#include <malloc.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 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) -{ - struct efi_priv *priv = efi_get_priv(); - - if (ch == '\n') - putc('\r'); - - if (use_uart) { - struct ns16550 *com_port = (struct ns16550 *)0x3f8; - - while ((inb((ulong)&com_port->lsr) & UART_LSR_THRE) == 0) - ; - outb(ch, (ulong)&com_port->thr); - } else { - efi_putc(priv, ch); - } -} - -void puts(const char *str) -{ - while (*str) - putc(*str++); -} - -static inline 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_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_TEXT_BASE > base && - CONFIG_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; -} - -/** - * setup_info_table() - sets up a table containing information from EFI - * - * We must call exit_boot_services() before jumping out of the stub into U-Boot - * proper, so that U-Boot has full control of peripherals, memory, etc. - * - * Once we do this, we cannot call any boot-services functions so we must find - * out everything we need to before doing that. - * - * Set up a struct efi_info_hdr table which can hold various records (e.g. - * struct efi_entry_memmap) with information obtained from EFI. - * - * @priv: Pointer to our private information which contains the list - * @size: Size of the table to allocate - * Return: 0 if OK, non-zero on error - */ -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; -} - -/** - * add_entry_addr() - Add a new entry to the efi_info list - * - * This adds an entry, consisting of a tag and two lots of data. This avoids the - * caller having to coalesce the data first - * - * @priv: Pointer to our private information which contains the list - * @type: Type of the entry to add - * @ptr1: Pointer to first data block to add - * @size1: Size of first data block in bytes (can be 0) - * @ptr2: Pointer to second data block to add - * @size2: Size of second data block in bytes (can be 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_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_status_t ret; - int cs32; - - ret = efi_init(priv, "Payload", image, sys_table); - if (ret) { - printhex2(ret); - puts(" efi_init() failed\n"); - return ret; - } - efi_set_priv(priv); - - cs32 = get_codeseg32(); - if (cs32 < 0) - return EFI_UNSUPPORTED; - - ret = efi_store_memory_map(priv); - if (ret) - return ret; - - ret = setup_info_table(priv, priv->memmap_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)); - } - - table.sys_table = (ulong)sys_table; - add_entry_addr(priv, EFIET_SYS_TABLE, &table, sizeof(table), NULL, 0); - - ret = efi_call_exit_boot_services(); - if (ret) - return ret; - - /* The EFI UART won't work now, switch to a debug one */ - use_uart = true; - - map.version = priv->memmap_version; - map.desc_size = priv->memmap_desc_size; - add_entry_addr(priv, EFIET_MEMORY_MAP, &map, sizeof(map), - priv->memmap_desc, priv->memmap_size); - add_entry_addr(priv, EFIET_END, NULL, 0, 0, 0); - - memcpy((void *)CONFIG_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_TEXT_BASE, (ulong)priv->info); - - return EFI_LOAD_ERROR; -} |