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 #include <asm/serial.h> 16 17 #ifdef CONFIG_SERIAL_EARLYCON 18 19 static unsigned int __initdata arc_base_baud; 20 21 unsigned int __init arc_early_base_baud(void) 22 { 23 return arc_base_baud/16; 24 } 25 26 static void __init arc_set_early_base_baud(unsigned long dt_root) 27 { 28 if (of_flat_dt_is_compatible(dt_root, "abilis,arc-tb10x")) 29 arc_base_baud = 166666666; /* Fixed 166.6MHz clk (TB10x) */ 30 else if (of_flat_dt_is_compatible(dt_root, "snps,arc-sdp") || 31 of_flat_dt_is_compatible(dt_root, "snps,hsdk")) 32 arc_base_baud = 33333333; /* Fixed 33MHz clk (AXS10x & HSDK) */ 33 else 34 arc_base_baud = 50000000; /* Fixed default 50MHz */ 35 } 36 #else 37 #define arc_set_early_base_baud(dt_root) 38 #endif 39 40 static const void * __init arch_get_next_mach(const char *const **match) 41 { 42 static const struct machine_desc *mdesc = __arch_info_begin; 43 const struct machine_desc *m = mdesc; 44 45 if (m >= __arch_info_end) 46 return NULL; 47 48 mdesc++; 49 *match = m->dt_compat; 50 return m; 51 } 52 53 /** 54 * setup_machine_fdt - Machine setup when an dtb was passed to the kernel 55 * @dt: virtual address pointer to dt blob 56 * 57 * If a dtb was passed to the kernel, then use it to choose the correct 58 * machine_desc and to setup the system. 59 */ 60 const struct machine_desc * __init setup_machine_fdt(void *dt) 61 { 62 const struct machine_desc *mdesc; 63 unsigned long dt_root; 64 65 if (!early_init_dt_scan(dt)) 66 return NULL; 67 68 mdesc = of_flat_dt_match_machine(NULL, arch_get_next_mach); 69 if (!mdesc) 70 machine_halt(); 71 72 dt_root = of_get_flat_dt_root(); 73 arc_set_early_base_baud(dt_root); 74 75 return mdesc; 76 } 77