[TG3]: Set minimal hw interrupt mitigation.
[linux-2.6/verdex.git] / arch / alpha / kernel / sys_jensen.c
blobfcabb7c96a16588f7367eb554d7b3ad8b9ee3047
1 /*
2 * linux/arch/alpha/kernel/sys_jensen.c
4 * Copyright (C) 1995 Linus Torvalds
5 * Copyright (C) 1998, 1999 Richard Henderson
7 * Code supporting the Jensen.
8 */
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>
17 #include <asm/ptrace.h>
18 #include <asm/system.h>
20 #define __EXTERN_INLINE inline
21 #include <asm/io.h>
22 #include <asm/jensen.h>
23 #undef __EXTERN_INLINE
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>
31 #include "proto.h"
32 #include "irq_impl.h"
33 #include "pci_impl.h"
34 #include "machvec_impl.h"
38 * Jensen is special: the vector is 0x8X0 for EISA interrupt X, and
39 * 0x9X0 for the local motherboard interrupts.
41 * Note especially that those local interrupts CANNOT be masked,
42 * which causes much of the pain below...
44 * 0x660 - NMI
46 * 0x800 - IRQ0 interval timer (not used, as we use the RTC timer)
47 * 0x810 - IRQ1 line printer (duh..)
48 * 0x860 - IRQ6 floppy disk
50 * 0x900 - COM1
51 * 0x920 - COM2
52 * 0x980 - keyboard
53 * 0x990 - mouse
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.
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.
65 static unsigned int
66 jensen_local_startup(unsigned int irq)
68 /* the parport is really hw IRQ 1, silly Jensen. */
69 if (irq == 7)
70 i8259a_startup_irq(1);
71 else
73 * For all true local interrupts, set the flag that prevents
74 * the IPL from being dropped during handler processing.
76 if (irq_desc[irq].action)
77 irq_desc[irq].action->flags |= SA_INTERRUPT;
78 return 0;
81 static void
82 jensen_local_shutdown(unsigned int irq)
84 /* the parport is really hw IRQ 1, silly Jensen. */
85 if (irq == 7)
86 i8259a_disable_irq(1);
89 static void
90 jensen_local_enable(unsigned int irq)
92 /* the parport is really hw IRQ 1, silly Jensen. */
93 if (irq == 7)
94 i8259a_enable_irq(1);
97 static void
98 jensen_local_disable(unsigned int irq)
100 /* the parport is really hw IRQ 1, silly Jensen. */
101 if (irq == 7)
102 i8259a_disable_irq(1);
105 static void
106 jensen_local_ack(unsigned int irq)
108 /* the parport is really hw IRQ 1, silly Jensen. */
109 if (irq == 7)
110 i8259a_mask_and_ack_irq(1);
113 static void
114 jensen_local_end(unsigned int irq)
116 /* the parport is really hw IRQ 1, silly Jensen. */
117 if (irq == 7)
118 i8259a_end_irq(1);
121 static struct hw_interrupt_type jensen_local_irq_type = {
122 .typename = "LOCAL",
123 .startup = jensen_local_startup,
124 .shutdown = jensen_local_shutdown,
125 .enable = jensen_local_enable,
126 .disable = jensen_local_disable,
127 .ack = jensen_local_ack,
128 .end = jensen_local_end,
131 static void
132 jensen_device_interrupt(unsigned long vector, struct pt_regs * regs)
134 int irq;
136 switch (vector) {
137 case 0x660:
138 printk("Whee.. NMI received. Probable hardware error\n");
139 printk("61=%02x, 461=%02x\n", inb(0x61), inb(0x461));
140 return;
142 /* local device interrupts: */
143 case 0x900: irq = 4; break; /* com1 -> irq 4 */
144 case 0x920: irq = 3; break; /* com2 -> irq 3 */
145 case 0x980: irq = 1; break; /* kbd -> irq 1 */
146 case 0x990: irq = 9; break; /* mouse -> irq 9 */
148 default:
149 if (vector > 0x900) {
150 printk("Unknown local interrupt %lx\n", vector);
151 return;
154 irq = (vector - 0x800) >> 4;
155 if (irq == 1)
156 irq = 7;
157 break;
160 /* If there is no handler yet... */
161 if (irq_desc[irq].action == NULL) {
162 /* If it is a local interrupt that cannot be masked... */
163 if (vector >= 0x900)
165 /* Clear keyboard/mouse state */
166 inb(0x64);
167 inb(0x60);
168 /* Reset serial ports */
169 inb(0x3fa);
170 inb(0x2fa);
171 outb(0x0c, 0x3fc);
172 outb(0x0c, 0x2fc);
173 /* Clear NMI */
174 outb(0,0x61);
175 outb(0,0x461);
179 #if 0
180 /* A useful bit of code to find out if an interrupt is going wild. */
182 static unsigned int last_msg = 0, last_cc = 0;
183 static int last_irq = -1, count = 0;
184 unsigned int cc;
186 __asm __volatile("rpcc %0" : "=r"(cc));
187 ++count;
188 #define JENSEN_CYCLES_PER_SEC (150000000)
189 if (cc - last_msg > ((JENSEN_CYCLES_PER_SEC) * 3) ||
190 irq != last_irq) {
191 printk(KERN_CRIT " irq %d count %d cc %u @ %lx\n",
192 irq, count, cc-last_cc, regs->pc);
193 count = 0;
194 last_msg = cc;
195 last_irq = irq;
197 last_cc = cc;
199 #endif
201 handle_irq(irq, regs);
204 static void __init
205 jensen_init_irq(void)
207 init_i8259a_irqs();
209 irq_desc[1].handler = &jensen_local_irq_type;
210 irq_desc[4].handler = &jensen_local_irq_type;
211 irq_desc[3].handler = &jensen_local_irq_type;
212 irq_desc[7].handler = &jensen_local_irq_type;
213 irq_desc[9].handler = &jensen_local_irq_type;
215 common_init_isa_dma();
218 static void __init
219 jensen_init_arch(void)
221 struct pci_controller *hose;
222 #ifdef CONFIG_PCI
223 static struct pci_dev fake_isa_bridge = { .dma_mask = 0xffffffffUL, };
225 isa_bridge = &fake_isa_bridge;
226 #endif
228 /* Create a hose so that we can report i/o base addresses to
229 userland. */
231 pci_isa_hose = hose = alloc_pci_controller();
232 hose->io_space = &ioport_resource;
233 hose->mem_space = &iomem_resource;
234 hose->index = 0;
236 hose->sparse_mem_base = EISA_MEM - IDENT_ADDR;
237 hose->dense_mem_base = 0;
238 hose->sparse_io_base = EISA_IO - IDENT_ADDR;
239 hose->dense_io_base = 0;
241 hose->sg_isa = hose->sg_pci = NULL;
242 __direct_map_base = 0;
243 __direct_map_size = 0xffffffff;
246 static void
247 jensen_machine_check (u64 vector, u64 la, struct pt_regs *regs)
249 printk(KERN_CRIT "Machine check\n");
254 * The System Vector
257 struct alpha_machine_vector jensen_mv __initmv = {
258 .vector_name = "Jensen",
259 DO_EV4_MMU,
260 IO_LITE(JENSEN,jensen),
261 .machine_check = jensen_machine_check,
262 .max_isa_dma_address = ALPHA_MAX_ISA_DMA_ADDRESS,
263 .rtc_port = 0x170,
265 .nr_irqs = 16,
266 .device_interrupt = jensen_device_interrupt,
268 .init_arch = jensen_init_arch,
269 .init_irq = jensen_init_irq,
270 .init_rtc = common_init_rtc,
271 .init_pci = NULL,
272 .kill_arch = NULL,
274 ALIAS_MV(jensen)