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