1 /*
2 * Copyright (C) 2009-2010, Lars-Peter Clausen <lars@metafoo.de>
3 * Copyright (C) 2011, Maarten ter Huurne <maarten@treewalker.org>
4 * JZ4740 setup code
5 *
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License as published by the
8 * Free Software Foundation; either version 2 of the License, or (at your
9 * option) any later version.
10 *
11 * You should have received a copy of the GNU General Public License along
12 * with this program; if not, write to the Free Software Foundation, Inc.,
13 * 675 Mass Ave, Cambridge, MA 02139, USA.
14 *
15 */
16
17 #include <linux/init.h>
18 #include <linux/io.h>
19 #include <linux/irqchip.h>
20 #include <linux/kernel.h>
21 #include <linux/libfdt.h>
22 #include <linux/of_fdt.h>
23
24 #include <asm/bootinfo.h>
25 #include <asm/prom.h>
26
27 #include <asm/mach-jz4740/base.h>
28
29 #include "reset.h"
30
31
32 #define JZ4740_EMC_SDRAM_CTRL 0x80
33
34
jz4740_detect_mem(void)35 static void __init jz4740_detect_mem(void)
36 {
37 void __iomem *jz_emc_base;
38 u32 ctrl, bus, bank, rows, cols;
39 phys_addr_t size;
40
41 jz_emc_base = ioremap(JZ4740_EMC_BASE_ADDR, 0x100);
42 ctrl = readl(jz_emc_base + JZ4740_EMC_SDRAM_CTRL);
43 bus = 2 - ((ctrl >> 31) & 1);
44 bank = 1 + ((ctrl >> 19) & 1);
45 cols = 8 + ((ctrl >> 26) & 7);
46 rows = 11 + ((ctrl >> 20) & 3);
47 printk(KERN_DEBUG
48 "SDRAM preconfigured: bus:%u bank:%u rows:%u cols:%u\n",
49 bus, bank, rows, cols);
50 iounmap(jz_emc_base);
51
52 size = 1 << (bus + bank + cols + rows);
53 add_memory_region(0, size, BOOT_MEM_RAM);
54 }
55
plat_mem_setup(void)56 void __init plat_mem_setup(void)
57 {
58 int offset;
59
60 jz4740_reset_init();
61 __dt_setup_arch(__dtb_start);
62
63 offset = fdt_path_offset(__dtb_start, "/memory");
64 if (offset < 0)
65 jz4740_detect_mem();
66 }
67
device_tree_init(void)68 void __init device_tree_init(void)
69 {
70 if (!initial_boot_params)
71 return;
72
73 unflatten_and_copy_device_tree();
74 }
75
get_system_type(void)76 const char *get_system_type(void)
77 {
78 if (IS_ENABLED(CONFIG_MACH_JZ4780))
79 return "JZ4780";
80
81 return "JZ4740";
82 }
83
arch_init_irq(void)84 void __init arch_init_irq(void)
85 {
86 irqchip_init();
87 }
88