1// SPDX-License-Identifier: GPL-2.0
2/*
3 * linux/arch/alpha/kernel/sys_jensen.c
4 *
5 * Copyright (C) 1995 Linus Torvalds
6 * Copyright (C) 1998, 1999 Richard Henderson
7 *
8 * Code supporting the Jensen.
9 */
10#define __EXTERN_INLINE
11#include <asm/io.h>
12#include <asm/jensen.h>
13#undef __EXTERN_INLINE
14
15#include <linux/interrupt.h>
16#include <linux/kernel.h>
17#include <linux/types.h>
18#include <linux/mm.h>
19#include <linux/sched.h>
20#include <linux/pci.h>
21#include <linux/init.h>
22
23#include <asm/ptrace.h>
24
25#include <asm/dma.h>
26#include <asm/irq.h>
27#include <asm/mmu_context.h>
28#include <asm/tlbflush.h>
29
30#include "proto.h"
31#include "irq_impl.h"
32#include "pci_impl.h"
33#include "machvec_impl.h"
34
35
36/*
37 * Jensen is special: the vector is 0x8X0 for EISA interrupt X, and
38 * 0x9X0 for the local motherboard interrupts.
39 *
40 * Note especially that those local interrupts CANNOT be masked,
41 * which causes much of the pain below...
42 *
43 * 0x660 - NMI
44 *
45 * 0x800 - IRQ0 interval timer (not used, as we use the RTC timer)
46 * 0x810 - IRQ1 line printer (duh..)
47 * 0x860 - IRQ6 floppy disk
48 *
49 * 0x900 - COM1
50 * 0x920 - COM2
51 * 0x980 - keyboard
52 * 0x990 - mouse
53 *
54 * PCI-based systems are more sane: they don't have the local
55 * interrupts at all, and have only normal PCI interrupts from
56 * devices. Happily it's easy enough to do a sane mapping from the
57 * Jensen.
58 *
59 * Note that this means that we may have to do a hardware
60 * "local_op" to a different interrupt than we report to the rest of the
61 * world.
62 */
63
64static void
65jensen_local_enable(struct irq_data *d)
66{
67 /* the parport is really hw IRQ 1, silly Jensen. */
68 if (d->irq == 7)
69 i8259a_enable_irq(d);
70}
71
72static void
73jensen_local_disable(struct irq_data *d)
74{
75 /* the parport is really hw IRQ 1, silly Jensen. */
76 if (d->irq == 7)
77 i8259a_disable_irq(d);
78}
79
80static void
81jensen_local_mask_ack(struct irq_data *d)
82{
83 /* the parport is really hw IRQ 1, silly Jensen. */
84 if (d->irq == 7)
85 i8259a_mask_and_ack_irq(d);
86}
87
88static struct irq_chip jensen_local_irq_type = {
89 .name = "LOCAL",
90 .irq_unmask = jensen_local_enable,
91 .irq_mask = jensen_local_disable,
92 .irq_mask_ack = jensen_local_mask_ack,
93};
94
95static void
96jensen_device_interrupt(unsigned long vector)
97{
98 int irq;
99
100 switch (vector) {
101 case 0x660:
102 printk("Whee.. NMI received. Probable hardware error\n");
103 printk("61=%02x, 461=%02x\n", inb(0x61), inb(0x461));
104 return;
105
106 /* local device interrupts: */
107 case 0x900: irq = 4; break; /* com1 -> irq 4 */
108 case 0x920: irq = 3; break; /* com2 -> irq 3 */
109 case 0x980: irq = 1; break; /* kbd -> irq 1 */
110 case 0x990: irq = 9; break; /* mouse -> irq 9 */
111
112 default:
113 if (vector > 0x900) {
114 printk("Unknown local interrupt %lx\n", vector);
115 return;
116 }
117
118 irq = (vector - 0x800) >> 4;
119 if (irq == 1)
120 irq = 7;
121 break;
122 }
123
124 /* If there is no handler yet... */
125 if (!irq_has_action(irq)) {
126 /* If it is a local interrupt that cannot be masked... */
127 if (vector >= 0x900)
128 {
129 /* Clear keyboard/mouse state */
130 inb(port: 0x64);
131 inb(port: 0x60);
132 /* Reset serial ports */
133 inb(port: 0x3fa);
134 inb(port: 0x2fa);
135 outb(value: 0x0c, port: 0x3fc);
136 outb(value: 0x0c, port: 0x2fc);
137 /* Clear NMI */
138 outb(value: 0,port: 0x61);
139 outb(value: 0,port: 0x461);
140 }
141 }
142
143#if 0
144 /* A useful bit of code to find out if an interrupt is going wild. */
145 {
146 static unsigned int last_msg = 0, last_cc = 0;
147 static int last_irq = -1, count = 0;
148 unsigned int cc;
149
150 __asm __volatile("rpcc %0" : "=r"(cc));
151 ++count;
152#define JENSEN_CYCLES_PER_SEC (150000000)
153 if (cc - last_msg > ((JENSEN_CYCLES_PER_SEC) * 3) ||
154 irq != last_irq) {
155 printk(KERN_CRIT " irq %d count %d cc %u @ %lx\n",
156 irq, count, cc-last_cc, get_irq_regs()->pc);
157 count = 0;
158 last_msg = cc;
159 last_irq = irq;
160 }
161 last_cc = cc;
162 }
163#endif
164
165 handle_irq(irq);
166}
167
168static void __init
169jensen_init_irq(void)
170{
171 init_i8259a_irqs();
172
173 irq_set_chip_and_handler(irq: 1, chip: &jensen_local_irq_type, handle: handle_level_irq);
174 irq_set_chip_and_handler(irq: 4, chip: &jensen_local_irq_type, handle: handle_level_irq);
175 irq_set_chip_and_handler(irq: 3, chip: &jensen_local_irq_type, handle: handle_level_irq);
176 irq_set_chip_and_handler(irq: 7, chip: &jensen_local_irq_type, handle: handle_level_irq);
177 irq_set_chip_and_handler(irq: 9, chip: &jensen_local_irq_type, handle: handle_level_irq);
178
179 common_init_isa_dma();
180}
181
182static void __init
183jensen_init_arch(void)
184{
185 struct pci_controller *hose;
186#ifdef CONFIG_PCI
187 static struct pci_dev fake_isa_bridge = { .dma_mask = 0xffffffffUL, };
188
189 isa_bridge = &fake_isa_bridge;
190#endif
191
192 /* Create a hose so that we can report i/o base addresses to
193 userland. */
194
195 pci_isa_hose = hose = alloc_pci_controller();
196 hose->io_space = &ioport_resource;
197 hose->mem_space = &iomem_resource;
198 hose->index = 0;
199
200 hose->sparse_mem_base = EISA_MEM - IDENT_ADDR;
201 hose->dense_mem_base = 0;
202 hose->sparse_io_base = EISA_IO - IDENT_ADDR;
203 hose->dense_io_base = 0;
204
205 hose->sg_isa = hose->sg_pci = NULL;
206 __direct_map_base = 0;
207 __direct_map_size = 0xffffffff;
208}
209
210static void
211jensen_machine_check(unsigned long vector, unsigned long la)
212{
213 printk(KERN_CRIT "Machine check\n");
214}
215
216/*
217 * The System Vector
218 */
219
220struct alpha_machine_vector jensen_mv __initmv = {
221 .vector_name = "Jensen",
222 DO_EV4_MMU,
223 IO_LITE(JENSEN,jensen),
224 .machine_check = jensen_machine_check,
225 .max_isa_dma_address = ALPHA_MAX_ISA_DMA_ADDRESS,
226 .rtc_port = 0x170,
227
228 .nr_irqs = 16,
229 .device_interrupt = jensen_device_interrupt,
230
231 .init_arch = jensen_init_arch,
232 .init_irq = jensen_init_irq,
233 .init_rtc = common_init_rtc,
234 .init_pci = NULL,
235 .kill_arch = NULL,
236};
237ALIAS_MV(jensen)
238

source code of linux/arch/alpha/kernel/sys_jensen.c