1 /* SPDX-License-Identifier: GPL-2.0+ */ 2 /* 3 * Copyright (C) 2014, Bin Meng <bmeng.cn (at) gmail.com> 4 */ 5 6 #include <config.h> 7 #include <asm/post.h> 8 9 .globl car_init 10 car_init: 11 /* 12 * Note: ebp holds the BIST value (built-in self test) so far, but ebp 13 * will be destroyed through the FSP call, thus we have to test the 14 * BIST value here before we call into FSP. 15 */ 16 test %ebp, %ebp 17 jz car_init_start 18 post_code(POST_BIST_FAILURE) 19 jmp die 20 21 car_init_start: 22 post_code(POST_CAR_START) 23 lea find_fsp_header_romstack, %esp 24 jmp find_fsp_header 25 26 find_fsp_header_ret: 27 /* EAX points to FSP_INFO_HEADER */ 28 mov %eax, %ebp 29 30 /* sanity test */ 31 cmp $CONFIG_FSP_ADDR, %eax 32 jb die 33 34 /* calculate TempRamInitEntry address */ 35 mov 0x30(%ebp), %eax 36 add 0x1c(%ebp), %eax 37 38 /* call FSP TempRamInitEntry to setup temporary stack */ 39 lea temp_ram_init_romstack, %esp 40 jmp *%eax 41 42 temp_ram_init_ret: 43 addl $4, %esp 44 cmp $0, %eax 45 jnz car_init_fail 46 47 post_code(POST_CAR_CPU_CACHE) 48 49 /* 50 * The FSP TempRamInit initializes the ecx and edx registers to 51 * point to a temporary but writable memory range (Cache-As-RAM). 52 * ecx: the start of this temporary memory range, 53 * edx: the end of this range. 54 */ 55 56 /* stack grows down from top of CAR */ 57 movl %edx, %esp 58 subl $4, %esp 59 60 xor %esi, %esi 61 jmp car_init_done 62 63 .global fsp_init_done 64 fsp_init_done: 65 /* 66 * We come here from fsp_continue() with eax pointing to the HOB list. 67 * Save eax to esi temporarily. 68 */ 69 movl %eax, %esi 70 71 car_init_done: 72 /* 73 * Re-initialize the ebp (BIST) to zero, as we already reach here 74 * which means we passed BIST testing before. 75 */ 76 xorl %ebp, %ebp 77 jmp car_init_ret 78 79 car_init_fail: 80 post_code(POST_CAR_FAILURE) 81 82 die: 83 hlt 84 jmp die 85 hlt 86 87 /* 88 * The function call before CAR initialization is tricky. It cannot 89 * be called using the 'call' instruction but only the 'jmp' with 90 * the help of a handcrafted stack in the ROM. The stack needs to 91 * contain the function return address as well as the parameters. 92 */ 93 .balign 4 94 find_fsp_header_romstack: 95 .long find_fsp_header_ret 96 97 .balign 4 98 temp_ram_init_romstack: 99 .long temp_ram_init_ret 100 .long temp_ram_init_params 101 temp_ram_init_params: 102 _dt_ucode_base_size: 103 /* These next two fields are filled in by ifdtool */ 104 .globl ucode_base 105 ucode_base: /* Declared in microcode.h */ 106 .long 0 /* microcode base */ 107 .globl ucode_size 108 ucode_size: /* Declared in microcode.h */ 109 .long 0 /* microcode size */ 110 .long CONFIG_SYS_MONITOR_BASE /* code region base */ 111 .long CONFIG_SYS_MONITOR_LEN /* code region size */ 112
