1 /*
2  *	linux/arch/alpha/kernel/sys_jensen.c
3  *
4  *	Copyright (C) 1995 Linus Torvalds
5  *	Copyright (C) 1998, 1999 Richard Henderson
6  *
7  * Code supporting the Jensen.
8  */
9 
10 #include <linux/kernel.h>
11 #include <linux/types.h>
12 #include <linux/mm.h>
13 #include <linux/sched.h>
14 #include <linux/pci.h>
15 #include <linux/init.h>
16 
17 #include <asm/ptrace.h>
18 #include <asm/system.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 
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 
64 static unsigned int
jensen_local_startup(unsigned int irq)65 jensen_local_startup(unsigned int irq)
66 {
67 	/* the parport is really hw IRQ 1, silly Jensen.  */
68 	if (irq == 7)
69 		i8259a_startup_irq(1);
70 	else
71 		/*
72 		 * For all true local interrupts, set the flag that prevents
73 		 * the IPL from being dropped during handler processing.
74 		 */
75 		if (irq_desc[irq].action)
76 			irq_desc[irq].action->flags |= SA_INTERRUPT;
77 	return 0;
78 }
79 
80 static void
jensen_local_shutdown(unsigned int irq)81 jensen_local_shutdown(unsigned int irq)
82 {
83 	/* the parport is really hw IRQ 1, silly Jensen.  */
84 	if (irq == 7)
85 		i8259a_disable_irq(1);
86 }
87 
88 static void
jensen_local_enable(unsigned int irq)89 jensen_local_enable(unsigned int irq)
90 {
91 	/* the parport is really hw IRQ 1, silly Jensen.  */
92 	if (irq == 7)
93 		i8259a_enable_irq(1);
94 }
95 
96 static void
jensen_local_disable(unsigned int irq)97 jensen_local_disable(unsigned int irq)
98 {
99 	/* the parport is really hw IRQ 1, silly Jensen.  */
100 	if (irq == 7)
101 		i8259a_disable_irq(1);
102 }
103 
104 static void
jensen_local_ack(unsigned int irq)105 jensen_local_ack(unsigned int irq)
106 {
107 	/* the parport is really hw IRQ 1, silly Jensen.  */
108 	if (irq == 7)
109 		i8259a_mask_and_ack_irq(1);
110 }
111 
112 static void
jensen_local_end(unsigned int irq)113 jensen_local_end(unsigned int irq)
114 {
115 	/* the parport is really hw IRQ 1, silly Jensen.  */
116 	if (irq == 7)
117 		i8259a_end_irq(1);
118 }
119 
120 static struct hw_interrupt_type jensen_local_irq_type = {
121 	typename:	"LOCAL",
122 	startup:	jensen_local_startup,
123 	shutdown:	jensen_local_shutdown,
124 	enable:		jensen_local_enable,
125 	disable:	jensen_local_disable,
126 	ack:		jensen_local_ack,
127 	end:		jensen_local_end,
128 };
129 
130 static void
jensen_device_interrupt(unsigned long vector,struct pt_regs * regs)131 jensen_device_interrupt(unsigned long vector, struct pt_regs * regs)
132 {
133 	int irq;
134 
135 	switch (vector) {
136 	case 0x660:
137 		printk("Whee.. NMI received. Probable hardware error\n");
138 		printk("61=%02x, 461=%02x\n", inb(0x61), inb(0x461));
139 		return;
140 
141 	/* local device interrupts: */
142 	case 0x900: irq = 4; break;		/* com1 -> irq 4 */
143 	case 0x920: irq = 3; break;		/* com2 -> irq 3 */
144 	case 0x980: irq = 1; break;		/* kbd -> irq 1 */
145 	case 0x990: irq = 9; break;		/* mouse -> irq 9 */
146 
147 	default:
148 		if (vector > 0x900) {
149 			printk("Unknown local interrupt %lx\n", vector);
150 			return;
151 		}
152 
153 		irq = (vector - 0x800) >> 4;
154 		if (irq == 1)
155 			irq = 7;
156 		break;
157 	}
158 
159 	/* If there is no handler yet... */
160 	if (irq_desc[irq].action == NULL) {
161 	    /* If it is a local interrupt that cannot be masked... */
162 	    if (vector >= 0x900)
163 	    {
164 	        /* Clear keyboard/mouse state */
165 	    	inb(0x64);
166 		inb(0x60);
167 		/* Reset serial ports */
168 		inb(0x3fa);
169 		inb(0x2fa);
170 		outb(0x0c, 0x3fc);
171 		outb(0x0c, 0x2fc);
172 		/* Clear NMI */
173 		outb(0,0x61);
174 		outb(0,0x461);
175 	    }
176 	}
177 
178 #if 0
179         /* A useful bit of code to find out if an interrupt is going wild.  */
180         {
181           static unsigned int last_msg = 0, last_cc = 0;
182           static int last_irq = -1, count = 0;
183           unsigned int cc;
184 
185           __asm __volatile("rpcc %0" : "=r"(cc));
186           ++count;
187 #define JENSEN_CYCLES_PER_SEC	(150000000)
188           if (cc - last_msg > ((JENSEN_CYCLES_PER_SEC) * 3) ||
189 	      irq != last_irq) {
190                 printk(KERN_CRIT " irq %d count %d cc %u @ %lx\n",
191                        irq, count, cc-last_cc, regs->pc);
192                 count = 0;
193                 last_msg = cc;
194                 last_irq = irq;
195           }
196           last_cc = cc;
197         }
198 #endif
199 
200 	handle_irq(irq, regs);
201 }
202 
203 static void __init
jensen_init_irq(void)204 jensen_init_irq(void)
205 {
206 	init_i8259a_irqs();
207 
208 	irq_desc[1].handler = &jensen_local_irq_type;
209 	irq_desc[4].handler = &jensen_local_irq_type;
210 	irq_desc[3].handler = &jensen_local_irq_type;
211 	irq_desc[7].handler = &jensen_local_irq_type;
212 	irq_desc[9].handler = &jensen_local_irq_type;
213 
214 	common_init_isa_dma();
215 }
216 
217 static void __init
jensen_init_arch(void)218 jensen_init_arch(void)
219 {
220 	struct pci_controller *hose;
221 
222 	/* Create a hose so that we can report i/o base addresses to
223 	   userland.  */
224 
225 	pci_isa_hose = hose = alloc_pci_controller();
226 	hose->io_space = &ioport_resource;
227 	hose->mem_space = &iomem_resource;
228 	hose->index = 0;
229 
230 	hose->sparse_mem_base = EISA_MEM - IDENT_ADDR;
231 	hose->dense_mem_base = 0;
232 	hose->sparse_io_base = EISA_IO - IDENT_ADDR;
233 	hose->dense_io_base = 0;
234 
235 	hose->sg_isa = hose->sg_pci = NULL;
236 	__direct_map_base = 0;
237 	__direct_map_size = 0xffffffff;
238 }
239 
240 static void
jensen_machine_check(u64 vector,u64 la,struct pt_regs * regs)241 jensen_machine_check (u64 vector, u64 la, struct pt_regs *regs)
242 {
243 	printk(KERN_CRIT "Machine check\n");
244 }
245 
246 #define jensen_pci_tbi	((void*)0)
247 
248 
249 /*
250  * The System Vector
251  */
252 
253 struct alpha_machine_vector jensen_mv __initmv = {
254 	vector_name:		"Jensen",
255 	DO_EV4_MMU,
256 	IO_LITE(JENSEN,jensen),
257 	BUS(jensen),
258 	machine_check:		jensen_machine_check,
259 	max_dma_address:	ALPHA_MAX_DMA_ADDRESS,
260 	rtc_port:		0x170,
261 
262 	nr_irqs:		16,
263 	device_interrupt:	jensen_device_interrupt,
264 
265 	init_arch:		jensen_init_arch,
266 	init_irq:		jensen_init_irq,
267 	init_rtc:		common_init_rtc,
268 	init_pci:		NULL,
269 	kill_arch:		NULL,
270 };
271 ALIAS_MV(jensen)
272