1 // SPDX-License-Identifier: GPL-2.0
2 /* Prom access routines for the sun3x */
3
4 #include <linux/types.h>
5 #include <linux/kernel.h>
6 #include <linux/tty.h>
7 #include <linux/console.h>
8 #include <linux/init.h>
9 #include <linux/mm.h>
10 #include <linux/string.h>
11
12 #include <asm/page.h>
13 #include <asm/setup.h>
14 #include <asm/traps.h>
15 #include <asm/sun3xprom.h>
16 #include <asm/idprom.h>
17 #include <asm/segment.h>
18 #include <asm/sun3ints.h>
19 #include <asm/openprom.h>
20 #include <asm/machines.h>
21
22 void (*sun3x_putchar)(int);
23 int (*sun3x_getchar)(void);
24 int (*sun3x_mayget)(void);
25 int (*sun3x_mayput)(int);
26 void (*sun3x_prom_reboot)(void);
27 e_vector sun3x_prom_abort;
28 struct linux_romvec *romvec;
29
30 /* prom vector table */
31 e_vector *sun3x_prom_vbr;
32
33 /* Handle returning to the prom */
sun3x_halt(void)34 void sun3x_halt(void)
35 {
36 unsigned long flags;
37
38 /* Disable interrupts while we mess with things */
39 local_irq_save(flags);
40
41 /* Restore prom vbr */
42 asm volatile ("movec %0,%%vbr" : : "r" ((void*)sun3x_prom_vbr));
43
44 /* Restore prom NMI clock */
45 // sun3x_disable_intreg(5);
46 sun3_enable_irq(7);
47
48 /* Let 'er rip */
49 asm volatile ("trap #14");
50
51 /* Restore everything */
52 sun3_disable_irq(7);
53 sun3_enable_irq(5);
54
55 asm volatile ("movec %0,%%vbr" : : "r" ((void*)vectors));
56 local_irq_restore(flags);
57 }
58
sun3x_reboot(void)59 void sun3x_reboot(void)
60 {
61 /* This never returns, don't bother saving things */
62 local_irq_disable();
63
64 /* Restore prom vbr */
65 asm volatile ("movec %0,%%vbr" : : "r" ((void*)sun3x_prom_vbr));
66
67 /* Restore prom NMI clock */
68 sun3_disable_irq(5);
69 sun3_enable_irq(7);
70
71 /* Let 'er rip */
72 (*romvec->pv_reboot)("vmlinux");
73 }
74
sun3x_prom_write(struct console * co,const char * s,unsigned int count)75 static void sun3x_prom_write(struct console *co, const char *s,
76 unsigned int count)
77 {
78 while (count--) {
79 if (*s == '\n')
80 sun3x_putchar('\r');
81 sun3x_putchar(*s++);
82 }
83 }
84
85 /* debug console - write-only */
86
87 static struct console sun3x_debug = {
88 .name = "debug",
89 .write = sun3x_prom_write,
90 .flags = CON_PRINTBUFFER,
91 .index = -1,
92 };
93
sun3x_prom_init(void)94 void __init sun3x_prom_init(void)
95 {
96 /* Read the vector table */
97
98 sun3x_putchar = *(void (**)(int)) (SUN3X_P_PUTCHAR);
99 sun3x_getchar = *(int (**)(void)) (SUN3X_P_GETCHAR);
100 sun3x_mayget = *(int (**)(void)) (SUN3X_P_MAYGET);
101 sun3x_mayput = *(int (**)(int)) (SUN3X_P_MAYPUT);
102 sun3x_prom_reboot = *(void (**)(void)) (SUN3X_P_REBOOT);
103 sun3x_prom_abort = *(e_vector *) (SUN3X_P_ABORT);
104 romvec = (struct linux_romvec *)SUN3X_PROM_BASE;
105
106 idprom_init();
107
108 if (!((idprom->id_machtype & SM_ARCH_MASK) == SM_SUN3X)) {
109 pr_warn("Machine reports strange type %02x\n",
110 idprom->id_machtype);
111 pr_warn("Pretending it's a 3/80, but very afraid...\n");
112 idprom->id_machtype = SM_SUN3X | SM_3_80;
113 }
114
115 /* point trap #14 at abort.
116 * XXX this is futile since we restore the vbr first - oops
117 */
118 vectors[VEC_TRAP14] = sun3x_prom_abort;
119 }
120
sun3x_debug_setup(char * arg)121 static int __init sun3x_debug_setup(char *arg)
122 {
123 /* If debug=prom was specified, start the debug console */
124 if (MACH_IS_SUN3X && !strcmp(arg, "prom"))
125 register_console(&sun3x_debug);
126 return 0;
127 }
128
129 early_param("debug", sun3x_debug_setup);
130
131 /* some prom functions to export */
prom_getintdefault(int node,char * property,int deflt)132 int prom_getintdefault(int node, char *property, int deflt)
133 {
134 return deflt;
135 }
136
prom_getbool(int node,char * prop)137 int prom_getbool (int node, char *prop)
138 {
139 return 1;
140 }
141
prom_printf(char * fmt,...)142 void prom_printf(char *fmt, ...)
143 {
144 }
145
prom_halt(void)146 void prom_halt (void)
147 {
148 sun3x_halt();
149 }
150
151 /* Get the idprom and stuff it into buffer 'idbuf'. Returns the
152 * format type. 'num_bytes' is the number of bytes that your idbuf
153 * has space for. Returns 0xff on error.
154 */
155 unsigned char
prom_get_idprom(char * idbuf,int num_bytes)156 prom_get_idprom(char *idbuf, int num_bytes)
157 {
158 int i;
159
160 /* make a copy of the idprom structure */
161 for (i = 0; i < num_bytes; i++)
162 idbuf[i] = ((char *)SUN3X_IDPROM)[i];
163
164 return idbuf[0];
165 }
166