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 if (of_flat_dt_is_compatible(dt_root, "ezchip,arc-nps")) 33 arc_base_baud = 800000000; /* Fixed 800MHz clk (NPS) */ 34 else 35 arc_base_baud = 50000000; /* Fixed default 50MHz */ 36 } 37 #else 38 #define arc_set_early_base_baud(dt_root) 39 #endif 40 41 static const void * __init arch_get_next_mach(const char *const **match) 42 { 43 static const struct machine_desc *mdesc = __arch_info_begin; 44 const struct machine_desc *m = mdesc; 45 46 if (m >= __arch_info_end) 47 return NULL; 48 49 mdesc++; 50 *match = m->dt_compat; 51 return m; 52 } 53 54 /** 55 * setup_machine_fdt - Machine setup when an dtb was passed to the kernel 56 * @dt: virtual address pointer to dt blob 57 * 58 * If a dtb was passed to the kernel, then use it to choose the correct 59 * machine_desc and to setup the system. 60 */ 61 const struct machine_desc * __init setup_machine_fdt(void *dt) 62 { 63 const struct machine_desc *mdesc; 64 unsigned long dt_root; 65 66 if (!early_init_dt_scan(dt)) 67 return NULL; 68 69 mdesc = of_flat_dt_match_machine(NULL, arch_get_next_mach); 70 if (!mdesc) 71 machine_halt(); 72 73 dt_root = of_get_flat_dt_root(); 74 arc_set_early_base_baud(dt_root); 75 76 return mdesc; 77 } 78