1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright (C) 2012 Synopsys, Inc. (www.synopsys.com) 4 * 5 * Based on reduced version of METAG 6 */ 7 8 9 #include <linux/init.h> 10 #include <linux/reboot.h> 11 #include <linux/memblock.h> 12 #include <linux/of.h> 13 #include <linux/of_fdt.h> 14 #include <asm/mach_desc.h> 15 16 #ifdef CONFIG_SERIAL_EARLYCON 17 18 static unsigned int __initdata arc_base_baud; 19 20 unsigned int __init arc_early_base_baud(void) 21 { 22 return arc_base_baud/16; 23 } 24 25 static void __init arc_set_early_base_baud(unsigned long dt_root) 26 { 27 if (of_flat_dt_is_compatible(dt_root, "abilis,arc-tb10x")) 28 arc_base_baud = 166666666; /* Fixed 166.6MHz clk (TB10x) */ 29 else if (of_flat_dt_is_compatible(dt_root, "snps,arc-sdp") || 30 of_flat_dt_is_compatible(dt_root, "snps,hsdk")) 31 arc_base_baud = 33333333; /* Fixed 33MHz clk (AXS10x & HSDK) */ 32 else 33 arc_base_baud = 50000000; /* Fixed default 50MHz */ 34 } 35 #else 36 #define arc_set_early_base_baud(dt_root) 37 #endif 38 39 static const void * __init arch_get_next_mach(const char *const **match) 40 { 41 static const struct machine_desc *mdesc = __arch_info_begin; 42 const struct machine_desc *m = mdesc; 43 44 if (m >= __arch_info_end) 45 return NULL; 46 47 mdesc++; 48 *match = m->dt_compat; 49 return m; 50 } 51 52 /** 53 * setup_machine_fdt - Machine setup when an dtb was passed to the kernel 54 * @dt: virtual address pointer to dt blob 55 * 56 * If a dtb was passed to the kernel, then use it to choose the correct 57 * machine_desc and to setup the system. 58 */ 59 const struct machine_desc * __init setup_machine_fdt(void *dt) 60 { 61 const struct machine_desc *mdesc; 62 unsigned long dt_root; 63 64 if (!early_init_dt_scan(dt)) 65 return NULL; 66 67 mdesc = of_flat_dt_match_machine(NULL, arch_get_next_mach); 68 if (!mdesc) 69 machine_halt(); 70 71 dt_root = of_get_flat_dt_root(); 72 arc_set_early_base_baud(dt_root); 73 74 return mdesc; 75 } 76