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/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(0x64);
131		inb(0x60);
132		/* Reset serial ports */
133		inb(0x3fa);
134		inb(0x2fa);
135		outb(0x0c, 0x3fc);
136		outb(0x0c, 0x2fc);
137		/* Clear NMI */
138		outb(0,0x61);
139		outb(0,0x461);
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(1, &jensen_local_irq_type, handle_level_irq);
174	irq_set_chip_and_handler(4, &jensen_local_irq_type, handle_level_irq);
175	irq_set_chip_and_handler(3, &jensen_local_irq_type, handle_level_irq);
176	irq_set_chip_and_handler(7, &jensen_local_irq_type, handle_level_irq);
177	irq_set_chip_and_handler(9, &jensen_local_irq_type, 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)