xref: /openbmc/linux/arch/alpha/kernel/sys_jensen.c (revision 2359ccdd)
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 
11 #include <linux/kernel.h>
12 #include <linux/types.h>
13 #include <linux/mm.h>
14 #include <linux/sched.h>
15 #include <linux/pci.h>
16 #include <linux/init.h>
17 
18 #include <asm/ptrace.h>
19 
20 #define __EXTERN_INLINE inline
21 #include <asm/io.h>
22 #include <asm/jensen.h>
23 #undef  __EXTERN_INLINE
24 
25 #include <asm/dma.h>
26 #include <asm/irq.h>
27 #include <asm/mmu_context.h>
28 #include <asm/pgtable.h>
29 #include <asm/tlbflush.h>
30 
31 #include "proto.h"
32 #include "irq_impl.h"
33 #include "pci_impl.h"
34 #include "machvec_impl.h"
35 
36 
37 /*
38  * Jensen is special: the vector is 0x8X0 for EISA interrupt X, and
39  * 0x9X0 for the local motherboard interrupts.
40  *
41  * Note especially that those local interrupts CANNOT be masked,
42  * which causes much of the pain below...
43  *
44  *	0x660 - NMI
45  *
46  *	0x800 - IRQ0  interval timer (not used, as we use the RTC timer)
47  *	0x810 - IRQ1  line printer (duh..)
48  *	0x860 - IRQ6  floppy disk
49  *
50  *	0x900 - COM1
51  *	0x920 - COM2
52  *	0x980 - keyboard
53  *	0x990 - mouse
54  *
55  * PCI-based systems are more sane: they don't have the local
56  * interrupts at all, and have only normal PCI interrupts from
57  * devices.  Happily it's easy enough to do a sane mapping from the
58  * Jensen.
59  *
60  * Note that this means that we may have to do a hardware
61  * "local_op" to a different interrupt than we report to the rest of the
62  * world.
63  */
64 
65 static void
66 jensen_local_enable(struct irq_data *d)
67 {
68 	/* the parport is really hw IRQ 1, silly Jensen.  */
69 	if (d->irq == 7)
70 		i8259a_enable_irq(d);
71 }
72 
73 static void
74 jensen_local_disable(struct irq_data *d)
75 {
76 	/* the parport is really hw IRQ 1, silly Jensen.  */
77 	if (d->irq == 7)
78 		i8259a_disable_irq(d);
79 }
80 
81 static void
82 jensen_local_mask_ack(struct irq_data *d)
83 {
84 	/* the parport is really hw IRQ 1, silly Jensen.  */
85 	if (d->irq == 7)
86 		i8259a_mask_and_ack_irq(d);
87 }
88 
89 static struct irq_chip jensen_local_irq_type = {
90 	.name		= "LOCAL",
91 	.irq_unmask	= jensen_local_enable,
92 	.irq_mask	= jensen_local_disable,
93 	.irq_mask_ack	= jensen_local_mask_ack,
94 };
95 
96 static void
97 jensen_device_interrupt(unsigned long vector)
98 {
99 	int irq;
100 
101 	switch (vector) {
102 	case 0x660:
103 		printk("Whee.. NMI received. Probable hardware error\n");
104 		printk("61=%02x, 461=%02x\n", inb(0x61), inb(0x461));
105 		return;
106 
107 	/* local device interrupts: */
108 	case 0x900: irq = 4; break;		/* com1 -> irq 4 */
109 	case 0x920: irq = 3; break;		/* com2 -> irq 3 */
110 	case 0x980: irq = 1; break;		/* kbd -> irq 1 */
111 	case 0x990: irq = 9; break;		/* mouse -> irq 9 */
112 
113 	default:
114 		if (vector > 0x900) {
115 			printk("Unknown local interrupt %lx\n", vector);
116 			return;
117 		}
118 
119 		irq = (vector - 0x800) >> 4;
120 		if (irq == 1)
121 			irq = 7;
122 		break;
123 	}
124 
125 	/* If there is no handler yet... */
126 	if (!irq_has_action(irq)) {
127 	    /* If it is a local interrupt that cannot be masked... */
128 	    if (vector >= 0x900)
129 	    {
130 	        /* Clear keyboard/mouse state */
131 	    	inb(0x64);
132 		inb(0x60);
133 		/* Reset serial ports */
134 		inb(0x3fa);
135 		inb(0x2fa);
136 		outb(0x0c, 0x3fc);
137 		outb(0x0c, 0x2fc);
138 		/* Clear NMI */
139 		outb(0,0x61);
140 		outb(0,0x461);
141 	    }
142 	}
143 
144 #if 0
145         /* A useful bit of code to find out if an interrupt is going wild.  */
146         {
147           static unsigned int last_msg = 0, last_cc = 0;
148           static int last_irq = -1, count = 0;
149           unsigned int cc;
150 
151           __asm __volatile("rpcc %0" : "=r"(cc));
152           ++count;
153 #define JENSEN_CYCLES_PER_SEC	(150000000)
154           if (cc - last_msg > ((JENSEN_CYCLES_PER_SEC) * 3) ||
155 	      irq != last_irq) {
156                 printk(KERN_CRIT " irq %d count %d cc %u @ %lx\n",
157                        irq, count, cc-last_cc, get_irq_regs()->pc);
158                 count = 0;
159                 last_msg = cc;
160                 last_irq = irq;
161           }
162           last_cc = cc;
163         }
164 #endif
165 
166 	handle_irq(irq);
167 }
168 
169 static void __init
170 jensen_init_irq(void)
171 {
172 	init_i8259a_irqs();
173 
174 	irq_set_chip_and_handler(1, &jensen_local_irq_type, handle_level_irq);
175 	irq_set_chip_and_handler(4, &jensen_local_irq_type, handle_level_irq);
176 	irq_set_chip_and_handler(3, &jensen_local_irq_type, handle_level_irq);
177 	irq_set_chip_and_handler(7, &jensen_local_irq_type, handle_level_irq);
178 	irq_set_chip_and_handler(9, &jensen_local_irq_type, handle_level_irq);
179 
180 	common_init_isa_dma();
181 }
182 
183 static void __init
184 jensen_init_arch(void)
185 {
186 	struct pci_controller *hose;
187 #ifdef CONFIG_PCI
188 	static struct pci_dev fake_isa_bridge = { .dma_mask = 0xffffffffUL, };
189 
190 	isa_bridge = &fake_isa_bridge;
191 #endif
192 
193 	/* Create a hose so that we can report i/o base addresses to
194 	   userland.  */
195 
196 	pci_isa_hose = hose = alloc_pci_controller();
197 	hose->io_space = &ioport_resource;
198 	hose->mem_space = &iomem_resource;
199 	hose->index = 0;
200 
201 	hose->sparse_mem_base = EISA_MEM - IDENT_ADDR;
202 	hose->dense_mem_base = 0;
203 	hose->sparse_io_base = EISA_IO - IDENT_ADDR;
204 	hose->dense_io_base = 0;
205 
206 	hose->sg_isa = hose->sg_pci = NULL;
207 	__direct_map_base = 0;
208 	__direct_map_size = 0xffffffff;
209 }
210 
211 static void
212 jensen_machine_check(unsigned long vector, unsigned long la)
213 {
214 	printk(KERN_CRIT "Machine check\n");
215 }
216 
217 /*
218  * The System Vector
219  */
220 
221 struct alpha_machine_vector jensen_mv __initmv = {
222 	.vector_name		= "Jensen",
223 	DO_EV4_MMU,
224 	IO_LITE(JENSEN,jensen),
225 	.machine_check		= jensen_machine_check,
226 	.max_isa_dma_address	= ALPHA_MAX_ISA_DMA_ADDRESS,
227 	.rtc_port		= 0x170,
228 
229 	.nr_irqs		= 16,
230 	.device_interrupt	= jensen_device_interrupt,
231 
232 	.init_arch		= jensen_init_arch,
233 	.init_irq		= jensen_init_irq,
234 	.init_rtc		= common_init_rtc,
235 	.init_pci		= NULL,
236 	.kill_arch		= NULL,
237 };
238 ALIAS_MV(jensen)
239