1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Copyright (C) 2020 Western Digital Corporation or its affiliates. 4 */ 5 #include <linux/init.h> 6 #include <linux/libfdt.h> 7 #include <linux/pgtable.h> 8 #include <asm/soc.h> 9 10 /* 11 * This is called extremly early, before parse_dtb(), to allow initializing 12 * SoC hardware before memory or any device driver initialization. 13 */ 14 void __init soc_early_init(void) 15 { 16 void (*early_fn)(const void *fdt); 17 const struct of_device_id *s; 18 const void *fdt = dtb_early_va; 19 20 for (s = (void *)&__soc_early_init_table_start; 21 (void *)s < (void *)&__soc_early_init_table_end; s++) { 22 if (!fdt_node_check_compatible(fdt, 0, s->compatible)) { 23 early_fn = s->data; 24 early_fn(fdt); 25 return; 26 } 27 } 28 } 29 30 static bool soc_builtin_dtb_match(unsigned long vendor_id, 31 unsigned long arch_id, unsigned long imp_id, 32 const struct soc_builtin_dtb *entry) 33 { 34 return entry->vendor_id == vendor_id && 35 entry->arch_id == arch_id && 36 entry->imp_id == imp_id; 37 } 38 39 void * __init soc_lookup_builtin_dtb(void) 40 { 41 unsigned long vendor_id, arch_id, imp_id; 42 const struct soc_builtin_dtb *s; 43 44 __asm__ ("csrr %0, mvendorid" : "=r"(vendor_id)); 45 __asm__ ("csrr %0, marchid" : "=r"(arch_id)); 46 __asm__ ("csrr %0, mimpid" : "=r"(imp_id)); 47 48 for (s = (void *)&__soc_builtin_dtb_table_start; 49 (void *)s < (void *)&__soc_builtin_dtb_table_end; s++) { 50 if (soc_builtin_dtb_match(vendor_id, arch_id, imp_id, s)) 51 return s->dtb_func(); 52 } 53 54 return NULL; 55 } 56