1 /*
2 * Copyright (C) 1999, 2000, 2004, 2005 MIPS Technologies, Inc.
3 * All rights reserved.
4 * Authors: Carsten Langgaard <carstenl@mips.com>
5 * Maciej W. Rozycki <macro@mips.com>
6 * Portions copyright (C) 2009 Cisco Systems, Inc.
7 *
8 * This program is free software; you can distribute it and/or modify it
9 * under the terms of the GNU General Public License (Version 2) as
10 * published by the Free Software Foundation.
11 *
12 * This program is distributed in the hope it will be useful, but WITHOUT
13 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
15 * for more details.
16 *
17 * You should have received a copy of the GNU General Public License along
18 * with this program; if not, write to the Free Software Foundation, Inc.,
19 * 59 Temple Place - Suite 330, Boston MA 02111-1307, USA.
20 *
21 * PROM library initialisation code.
22 */
23 #include <linux/init.h>
24 #include <linux/string.h>
25 #include <linux/kernel.h>
26
27 #include <asm/bootinfo.h>
28 #include <linux/io.h>
29 #include <asm/system.h>
30 #include <asm/cacheflush.h>
31 #include <asm/traps.h>
32
33 #include <asm/mips-boards/prom.h>
34 #include <asm/mips-boards/generic.h>
35 #include <asm/mach-powertv/asic.h>
36
37 static int *_prom_envp;
38 unsigned long _prom_memsize;
39
40 /*
41 * YAMON (32-bit PROM) pass arguments and environment as 32-bit pointer.
42 * This macro take care of sign extension, if running in 64-bit mode.
43 */
44 #define prom_envp(index) ((char *)(long)_prom_envp[(index)])
45
prom_getenv(char * envname)46 char *prom_getenv(char *envname)
47 {
48 char *result = NULL;
49
50 if (_prom_envp != NULL) {
51 /*
52 * Return a pointer to the given environment variable.
53 * In 64-bit mode: we're using 64-bit pointers, but all pointers
54 * in the PROM structures are only 32-bit, so we need some
55 * workarounds, if we are running in 64-bit mode.
56 */
57 int i, index = 0;
58
59 i = strlen(envname);
60
61 while (prom_envp(index)) {
62 if (strncmp(envname, prom_envp(index), i) == 0) {
63 result = prom_envp(index + 1);
64 break;
65 }
66 index += 2;
67 }
68 }
69
70 return result;
71 }
72
73 /* TODO: Verify on linux-mips mailing list that the following two */
74 /* functions are correct */
75 /* TODO: Copy NMI and EJTAG exception vectors to memory from the */
76 /* BootROM exception vectors. Flush their cache entries. test it. */
77
mips_nmi_setup(void)78 static void __init mips_nmi_setup(void)
79 {
80 void *base;
81 #if defined(CONFIG_CPU_MIPS32_R1)
82 base = cpu_has_veic ?
83 (void *)(CAC_BASE + 0xa80) :
84 (void *)(CAC_BASE + 0x380);
85 #elif defined(CONFIG_CPU_MIPS32_R2)
86 base = (void *)0xbfc00000;
87 #else
88 #error NMI exception handler address not defined
89 #endif
90 }
91
mips_ejtag_setup(void)92 static void __init mips_ejtag_setup(void)
93 {
94 void *base;
95
96 #if defined(CONFIG_CPU_MIPS32_R1)
97 base = cpu_has_veic ?
98 (void *)(CAC_BASE + 0xa00) :
99 (void *)(CAC_BASE + 0x300);
100 #elif defined(CONFIG_CPU_MIPS32_R2)
101 base = (void *)0xbfc00480;
102 #else
103 #error EJTAG exception handler address not defined
104 #endif
105 }
106
prom_init(void)107 void __init prom_init(void)
108 {
109 int prom_argc;
110 char *prom_argv;
111
112 prom_argc = fw_arg0;
113 prom_argv = (char *) fw_arg1;
114 _prom_envp = (int *) fw_arg2;
115 _prom_memsize = (unsigned long) fw_arg3;
116
117 board_nmi_handler_setup = mips_nmi_setup;
118 board_ejtag_handler_setup = mips_ejtag_setup;
119
120 if (prom_argc == 1) {
121 strlcat(arcs_cmdline, " ", COMMAND_LINE_SIZE);
122 strlcat(arcs_cmdline, prom_argv, COMMAND_LINE_SIZE);
123 }
124
125 configure_platform();
126 prom_meminit();
127
128 #ifndef CONFIG_BOOTLOADER_DRIVER
129 pr_info("\nBootloader driver isn't loaded...\n");
130 #endif
131 }
132