1 /*
2 * Copyright (C) 2012 Synopsys, Inc. (www.synopsys.com)
3 *
4 * Based on reduced version of METAG
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 */
10
11
12 #include <linux/init.h>
13 #include <linux/reboot.h>
14 #include <linux/memblock.h>
15 #include <linux/of.h>
16 #include <linux/of_fdt.h>
17 #include <asm/mach_desc.h>
18
19 #ifdef CONFIG_SERIAL_EARLYCON
20
21 static unsigned int __initdata arc_base_baud;
22
arc_early_base_baud(void)23 unsigned int __init arc_early_base_baud(void)
24 {
25 return arc_base_baud/16;
26 }
27
arc_set_early_base_baud(unsigned long dt_root)28 static void __init arc_set_early_base_baud(unsigned long dt_root)
29 {
30 if (of_flat_dt_is_compatible(dt_root, "abilis,arc-tb10x"))
31 arc_base_baud = 166666666; /* Fixed 166.6MHz clk (TB10x) */
32 else if (of_flat_dt_is_compatible(dt_root, "snps,arc-sdp") ||
33 of_flat_dt_is_compatible(dt_root, "snps,hsdk"))
34 arc_base_baud = 33333333; /* Fixed 33MHz clk (AXS10x & HSDK) */
35 else if (of_flat_dt_is_compatible(dt_root, "ezchip,arc-nps"))
36 arc_base_baud = 800000000; /* Fixed 800MHz clk (NPS) */
37 else
38 arc_base_baud = 50000000; /* Fixed default 50MHz */
39 }
40 #else
41 #define arc_set_early_base_baud(dt_root)
42 #endif
43
arch_get_next_mach(const char * const ** match)44 static const void * __init arch_get_next_mach(const char *const **match)
45 {
46 static const struct machine_desc *mdesc = __arch_info_begin;
47 const struct machine_desc *m = mdesc;
48
49 if (m >= __arch_info_end)
50 return NULL;
51
52 mdesc++;
53 *match = m->dt_compat;
54 return m;
55 }
56
57 /**
58 * setup_machine_fdt - Machine setup when an dtb was passed to the kernel
59 * @dt: virtual address pointer to dt blob
60 *
61 * If a dtb was passed to the kernel, then use it to choose the correct
62 * machine_desc and to setup the system.
63 */
setup_machine_fdt(void * dt)64 const struct machine_desc * __init setup_machine_fdt(void *dt)
65 {
66 const struct machine_desc *mdesc;
67 unsigned long dt_root;
68
69 if (!early_init_dt_scan(dt))
70 return NULL;
71
72 mdesc = of_flat_dt_match_machine(NULL, arch_get_next_mach);
73 if (!mdesc)
74 machine_halt();
75
76 dt_root = of_get_flat_dt_root();
77 arc_set_early_base_baud(dt_root);
78
79 return mdesc;
80 }
81