1 /* 2 * Code shared between SPL and U-Boot proper 3 * 4 * Copyright (c) 2015 Google, Inc 5 * Written by Simon Glass <sjg@chromium.org> 6 * 7 * SPDX-License-Identifier: GPL-2.0+ 8 */ 9 10 #include <common.h> 11 12 DECLARE_GLOBAL_DATA_PTR; 13 14 /* 15 * It isn't trivial to figure out whether memcpy() exists. The arch-specific 16 * memcpy() is not normally available in SPL due to code size. 17 */ 18 #if !defined(CONFIG_SPL_BUILD) || \ 19 (defined(CONFIG_SPL_LIBGENERIC_SUPPORT) && \ 20 !defined(CONFIG_USE_ARCH_MEMSET)) 21 #define _USE_MEMCPY 22 #endif 23 24 /* Unfortunately x86 or ARM can't compile this code as gd cannot be assigned */ 25 #if !defined(CONFIG_X86) && !defined(CONFIG_ARM) 26 __weak void arch_setup_gd(struct global_data *gd_ptr) 27 { 28 gd = gd_ptr; 29 } 30 #endif /* !CONFIG_X86 && !CONFIG_ARM */ 31 32 /* 33 * Allocate reserved space for use as 'globals' from 'top' address and 34 * return 'bottom' address of allocated space 35 * 36 * Notes: 37 * 38 * Actual reservation cannot be done from within this function as 39 * it requires altering the C stack pointer, so this will be done by 40 * the caller upon return from this function. 41 * 42 * IMPORTANT: 43 * 44 * Alignment constraints may differ for each 'chunk' allocated. For now: 45 * 46 * - GD is aligned down on a 16-byte boundary 47 * 48 * - the early malloc arena is not aligned, therefore it follows the stack 49 * alignment constraint of the architecture for which we are bulding. 50 * 51 * - GD is allocated last, so that the return value of this functions is 52 * both the bottom of the reserved area and the address of GD, should 53 * the calling context need it. 54 */ 55 56 ulong board_init_f_alloc_reserve(ulong top) 57 { 58 /* Reserve early malloc arena */ 59 #if defined(CONFIG_SYS_MALLOC_F) 60 top -= CONFIG_SYS_MALLOC_F_LEN; 61 #endif 62 /* LAST : reserve GD (rounded up to a multiple of 16 bytes) */ 63 top = rounddown(top-sizeof(struct global_data), 16); 64 65 return top; 66 } 67 68 /* 69 * Initialize reserved space (which has been safely allocated on the C 70 * stack from the C runtime environment handling code). 71 * 72 * Notes: 73 * 74 * Actual reservation was done by the caller; the locations from base 75 * to base+size-1 (where 'size' is the value returned by the allocation 76 * function above) can be accessed freely without risk of corrupting the 77 * C runtime environment. 78 * 79 * IMPORTANT: 80 * 81 * Upon return from the allocation function above, on some architectures 82 * the caller will set gd to the lowest reserved location. Therefore, in 83 * this initialization function, the global data MUST be placed at base. 84 * 85 * ALSO IMPORTANT: 86 * 87 * On some architectures, gd will already be good when entering this 88 * function. On others, it will only be good once arch_setup_gd() returns. 89 * Therefore, global data accesses must be done: 90 * 91 * - through gd_ptr if before the call to arch_setup_gd(); 92 * 93 * - through gd once arch_setup_gd() has been called. 94 * 95 * Do not use 'gd->' until arch_setup_gd() has been called! 96 * 97 * IMPORTANT TOO: 98 * 99 * Initialization for each "chunk" (GD, early malloc arena...) ends with 100 * an incrementation line of the form 'base += <some size>'. The last of 101 * these incrementations seems useless, as base will not be used any 102 * more after this incrementation; but if/when a new "chunk" is appended, 103 * this increment will be essential as it will give base right value for 104 * this new chunk (which will have to end with its own incrementation 105 * statement). Besides, the compiler's optimizer will silently detect 106 * and remove the last base incrementation, therefore leaving that last 107 * (seemingly useless) incrementation causes no code increase. 108 */ 109 110 void board_init_f_init_reserve(ulong base) 111 { 112 struct global_data *gd_ptr; 113 #ifndef _USE_MEMCPY 114 int *ptr; 115 #endif 116 117 /* 118 * clear GD entirely and set it up. 119 * Use gd_ptr, as gd may not be properly set yet. 120 */ 121 122 gd_ptr = (struct global_data *)base; 123 /* zero the area */ 124 #ifdef _USE_MEMCPY 125 memset(gd_ptr, '\0', sizeof(*gd)); 126 #else 127 for (ptr = (int *)gd_ptr; ptr < (int *)(gd_ptr + 1); ) 128 *ptr++ = 0; 129 #endif 130 /* set GD unless architecture did it already */ 131 #if !defined(CONFIG_ARM) 132 arch_setup_gd(gd_ptr); 133 #endif 134 /* next alloc will be higher by one GD plus 16-byte alignment */ 135 base += roundup(sizeof(struct global_data), 16); 136 137 /* 138 * record early malloc arena start. 139 * Use gd as it is now properly set for all architectures. 140 */ 141 142 #if defined(CONFIG_SYS_MALLOC_F) 143 /* go down one 'early malloc arena' */ 144 gd->malloc_base = base; 145 /* next alloc will be higher by one 'early malloc arena' size */ 146 base += CONFIG_SYS_MALLOC_F_LEN; 147 #endif 148 } 149 150 /* 151 * Board-specific Platform code can reimplement show_boot_progress () if needed 152 */ 153 __weak void show_boot_progress(int val) {} 154