xref: /OK3568_Linux_fs/kernel/arch/powerpc/boot/simpleboot.c (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0-only
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun  * The simple platform -- for booting when firmware doesn't supply a device
4*4882a593Smuzhiyun  *                        tree or any platform configuration information.
5*4882a593Smuzhiyun  *                        All data is extracted from an embedded device tree
6*4882a593Smuzhiyun  *                        blob.
7*4882a593Smuzhiyun  *
8*4882a593Smuzhiyun  * Authors: Scott Wood <scottwood@freescale.com>
9*4882a593Smuzhiyun  *          Grant Likely <grant.likely@secretlab.ca>
10*4882a593Smuzhiyun  *
11*4882a593Smuzhiyun  * Copyright (c) 2007 Freescale Semiconductor, Inc.
12*4882a593Smuzhiyun  * Copyright (c) 2008 Secret Lab Technologies Ltd.
13*4882a593Smuzhiyun  */
14*4882a593Smuzhiyun 
15*4882a593Smuzhiyun #include "ops.h"
16*4882a593Smuzhiyun #include "types.h"
17*4882a593Smuzhiyun #include "io.h"
18*4882a593Smuzhiyun #include "stdio.h"
19*4882a593Smuzhiyun #include <libfdt.h>
20*4882a593Smuzhiyun 
21*4882a593Smuzhiyun BSS_STACK(4*1024);
22*4882a593Smuzhiyun 
23*4882a593Smuzhiyun extern int platform_specific_init(void) __attribute__((weak));
24*4882a593Smuzhiyun 
platform_init(unsigned long r3,unsigned long r4,unsigned long r5,unsigned long r6,unsigned long r7)25*4882a593Smuzhiyun void platform_init(unsigned long r3, unsigned long r4, unsigned long r5,
26*4882a593Smuzhiyun 		   unsigned long r6, unsigned long r7)
27*4882a593Smuzhiyun {
28*4882a593Smuzhiyun 	const u32 *na, *ns, *reg, *timebase;
29*4882a593Smuzhiyun 	u64 memsize64;
30*4882a593Smuzhiyun 	int node, size, i;
31*4882a593Smuzhiyun 
32*4882a593Smuzhiyun 	/* Make sure FDT blob is sane */
33*4882a593Smuzhiyun 	if (fdt_check_header(_dtb_start) != 0)
34*4882a593Smuzhiyun 		fatal("Invalid device tree blob\n");
35*4882a593Smuzhiyun 
36*4882a593Smuzhiyun 	/* Find the #address-cells and #size-cells properties */
37*4882a593Smuzhiyun 	node = fdt_path_offset(_dtb_start, "/");
38*4882a593Smuzhiyun 	if (node < 0)
39*4882a593Smuzhiyun 		fatal("Cannot find root node\n");
40*4882a593Smuzhiyun 	na = fdt_getprop(_dtb_start, node, "#address-cells", &size);
41*4882a593Smuzhiyun 	if (!na || (size != 4))
42*4882a593Smuzhiyun 		fatal("Cannot find #address-cells property");
43*4882a593Smuzhiyun 	ns = fdt_getprop(_dtb_start, node, "#size-cells", &size);
44*4882a593Smuzhiyun 	if (!ns || (size != 4))
45*4882a593Smuzhiyun 		fatal("Cannot find #size-cells property");
46*4882a593Smuzhiyun 
47*4882a593Smuzhiyun 	/* Find the memory range */
48*4882a593Smuzhiyun 	node = fdt_node_offset_by_prop_value(_dtb_start, -1, "device_type",
49*4882a593Smuzhiyun 					     "memory", sizeof("memory"));
50*4882a593Smuzhiyun 	if (node < 0)
51*4882a593Smuzhiyun 		fatal("Cannot find memory node\n");
52*4882a593Smuzhiyun 	reg = fdt_getprop(_dtb_start, node, "reg", &size);
53*4882a593Smuzhiyun 	if (size < (*na+*ns) * sizeof(u32))
54*4882a593Smuzhiyun 		fatal("cannot get memory range\n");
55*4882a593Smuzhiyun 
56*4882a593Smuzhiyun 	/* Only interested in memory based at 0 */
57*4882a593Smuzhiyun 	for (i = 0; i < *na; i++)
58*4882a593Smuzhiyun 		if (*reg++ != 0)
59*4882a593Smuzhiyun 			fatal("Memory range is not based at address 0\n");
60*4882a593Smuzhiyun 
61*4882a593Smuzhiyun 	/* get the memsize and truncate it to under 4G on 32 bit machines */
62*4882a593Smuzhiyun 	memsize64 = 0;
63*4882a593Smuzhiyun 	for (i = 0; i < *ns; i++)
64*4882a593Smuzhiyun 		memsize64 = (memsize64 << 32) | *reg++;
65*4882a593Smuzhiyun 	if (sizeof(void *) == 4 && memsize64 >= 0x100000000ULL)
66*4882a593Smuzhiyun 		memsize64 = 0xffffffff;
67*4882a593Smuzhiyun 
68*4882a593Smuzhiyun 	/* finally, setup the timebase */
69*4882a593Smuzhiyun 	node = fdt_node_offset_by_prop_value(_dtb_start, -1, "device_type",
70*4882a593Smuzhiyun 					     "cpu", sizeof("cpu"));
71*4882a593Smuzhiyun 	if (!node)
72*4882a593Smuzhiyun 		fatal("Cannot find cpu node\n");
73*4882a593Smuzhiyun 	timebase = fdt_getprop(_dtb_start, node, "timebase-frequency", &size);
74*4882a593Smuzhiyun 	if (timebase && (size == 4))
75*4882a593Smuzhiyun 		timebase_period_ns = 1000000000 / *timebase;
76*4882a593Smuzhiyun 
77*4882a593Smuzhiyun 	/* Now we have the memory size; initialize the heap */
78*4882a593Smuzhiyun 	simple_alloc_init(_end, memsize64 - (unsigned long)_end, 32, 64);
79*4882a593Smuzhiyun 
80*4882a593Smuzhiyun 	/* prepare the device tree and find the console */
81*4882a593Smuzhiyun 	fdt_init(_dtb_start);
82*4882a593Smuzhiyun 
83*4882a593Smuzhiyun 	if (platform_specific_init)
84*4882a593Smuzhiyun 		platform_specific_init();
85*4882a593Smuzhiyun 
86*4882a593Smuzhiyun 	serial_console_init();
87*4882a593Smuzhiyun }
88