xref: /linux/arch/alpha/kernel/sys_noritake.c (revision 4b132aacb0768ac1e652cf517097ea6f237214b9)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  *	linux/arch/alpha/kernel/sys_noritake.c
4  *
5  *	Copyright (C) 1995 David A Rusling
6  *	Copyright (C) 1996 Jay A Estabrook
7  *	Copyright (C) 1998, 1999 Richard Henderson
8  *
9  * Code supporting the NORITAKE (AlphaServer 1000A),
10  * CORELLE (AlphaServer 800), and ALCOR Primo (AlphaStation 600A).
11  */
12 
13 #include <linux/kernel.h>
14 #include <linux/types.h>
15 #include <linux/mm.h>
16 #include <linux/sched.h>
17 #include <linux/pci.h>
18 #include <linux/init.h>
19 #include <linux/bitops.h>
20 
21 #include <asm/ptrace.h>
22 #include <asm/mce.h>
23 #include <asm/dma.h>
24 #include <asm/irq.h>
25 #include <asm/mmu_context.h>
26 #include <asm/io.h>
27 #include <asm/core_cia.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 /* Note mask bit is true for ENABLED irqs.  */
36 static int cached_irq_mask;
37 
38 static inline void
39 noritake_update_irq_hw(int irq, int mask)
40 {
41 	int port = 0x54a;
42 	if (irq >= 32) {
43 	    mask >>= 16;
44 	    port = 0x54c;
45 	}
46 	outw(mask, port);
47 }
48 
49 static void
50 noritake_enable_irq(struct irq_data *d)
51 {
52 	noritake_update_irq_hw(d->irq, cached_irq_mask |= 1 << (d->irq - 16));
53 }
54 
55 static void
56 noritake_disable_irq(struct irq_data *d)
57 {
58 	noritake_update_irq_hw(d->irq, cached_irq_mask &= ~(1 << (d->irq - 16)));
59 }
60 
61 static struct irq_chip noritake_irq_type = {
62 	.name		= "NORITAKE",
63 	.irq_unmask	= noritake_enable_irq,
64 	.irq_mask	= noritake_disable_irq,
65 	.irq_mask_ack	= noritake_disable_irq,
66 };
67 
68 static void
69 noritake_device_interrupt(unsigned long vector)
70 {
71 	unsigned long pld;
72 	unsigned int i;
73 
74 	/* Read the interrupt summary registers of NORITAKE */
75 	pld = (((unsigned long) inw(0x54c) << 32)
76 	       | ((unsigned long) inw(0x54a) << 16)
77 	       | ((unsigned long) inb(0xa0) << 8)
78 	       | inb(0x20));
79 
80 	/*
81 	 * Now for every possible bit set, work through them and call
82 	 * the appropriate interrupt handler.
83 	 */
84 	while (pld) {
85 		i = ffz(~pld);
86 		pld &= pld - 1; /* clear least bit set */
87 		if (i < 16) {
88 			isa_device_interrupt(vector);
89 		} else {
90 			handle_irq(i);
91 		}
92 	}
93 }
94 
95 static void
96 noritake_srm_device_interrupt(unsigned long vector)
97 {
98 	int irq;
99 
100 	irq = (vector - 0x800) >> 4;
101 
102 	/*
103 	 * I really hate to do this, too, but the NORITAKE SRM console also
104 	 * reports PCI vectors *lower* than I expected from the bit numbers
105 	 * in the documentation.
106 	 * But I really don't want to change the fixup code for allocation
107 	 * of IRQs, nor the alpha_irq_mask maintenance stuff, both of which
108 	 * look nice and clean now.
109 	 * So, here's this additional grotty hack... :-(
110 	 */
111 	if (irq >= 16)
112 		irq = irq + 1;
113 
114 	handle_irq(irq);
115 }
116 
117 static void __init
118 noritake_init_irq(void)
119 {
120 	long i;
121 
122 	if (alpha_using_srm)
123 		alpha_mv.device_interrupt = noritake_srm_device_interrupt;
124 
125 	outw(0, 0x54a);
126 	outw(0, 0x54c);
127 
128 	for (i = 16; i < 48; ++i) {
129 		irq_set_chip_and_handler(i, &noritake_irq_type,
130 					 handle_level_irq);
131 		irq_set_status_flags(i, IRQ_LEVEL);
132 	}
133 
134 	init_i8259a_irqs();
135 	common_init_isa_dma();
136 }
137 
138 
139 /*
140  * PCI Fixup configuration.
141  *
142  * Summary @ 0x542, summary register #1:
143  * Bit      Meaning
144  * 0        All valid ints from summary regs 2 & 3
145  * 1        QLOGIC ISP1020A SCSI
146  * 2        Interrupt Line A from slot 0
147  * 3        Interrupt Line B from slot 0
148  * 4        Interrupt Line A from slot 1
149  * 5        Interrupt line B from slot 1
150  * 6        Interrupt Line A from slot 2
151  * 7        Interrupt Line B from slot 2
152  * 8        Interrupt Line A from slot 3
153  * 9        Interrupt Line B from slot 3
154  *10        Interrupt Line A from slot 4
155  *11        Interrupt Line B from slot 4
156  *12        Interrupt Line A from slot 5
157  *13        Interrupt Line B from slot 5
158  *14        Interrupt Line A from slot 6
159  *15        Interrupt Line B from slot 6
160  *
161  * Summary @ 0x544, summary register #2:
162  * Bit      Meaning
163  * 0        OR of all unmasked ints in SR #2
164  * 1        OR of secondary bus ints
165  * 2        Interrupt Line C from slot 0
166  * 3        Interrupt Line D from slot 0
167  * 4        Interrupt Line C from slot 1
168  * 5        Interrupt line D from slot 1
169  * 6        Interrupt Line C from slot 2
170  * 7        Interrupt Line D from slot 2
171  * 8        Interrupt Line C from slot 3
172  * 9        Interrupt Line D from slot 3
173  *10        Interrupt Line C from slot 4
174  *11        Interrupt Line D from slot 4
175  *12        Interrupt Line C from slot 5
176  *13        Interrupt Line D from slot 5
177  *14        Interrupt Line C from slot 6
178  *15        Interrupt Line D from slot 6
179  *
180  * The device to slot mapping looks like:
181  *
182  * Slot     Device
183  *  7       Intel PCI-EISA bridge chip
184  *  8       DEC PCI-PCI bridge chip
185  * 11       PCI on board slot 0
186  * 12       PCI on board slot 1
187  * 13       PCI on board slot 2
188  *
189  *
190  * This two layered interrupt approach means that we allocate IRQ 16 and
191  * above for PCI interrupts.  The IRQ relates to which bit the interrupt
192  * comes in on.  This makes interrupt processing much easier.
193  */
194 
195 static int
196 noritake_map_irq(const struct pci_dev *dev, u8 slot, u8 pin)
197 {
198 	static char irq_tab[15][5] = {
199 		/*INT    INTA   INTB   INTC   INTD */
200 		/* note: IDSELs 16, 17, and 25 are CORELLE only */
201 		{ 16+1,  16+1,  16+1,  16+1,  16+1},  /* IdSel 16,  QLOGIC */
202 		{   -1,    -1,    -1,    -1,    -1},  /* IdSel 17, S3 Trio64 */
203 		{   -1,    -1,    -1,    -1,    -1},  /* IdSel 18,  PCEB */
204 		{   -1,    -1,    -1,    -1,    -1},  /* IdSel 19,  PPB  */
205 		{   -1,    -1,    -1,    -1,    -1},  /* IdSel 20,  ???? */
206 		{   -1,    -1,    -1,    -1,    -1},  /* IdSel 21,  ???? */
207 		{ 16+2,  16+2,  16+3,  32+2,  32+3},  /* IdSel 22,  slot 0 */
208 		{ 16+4,  16+4,  16+5,  32+4,  32+5},  /* IdSel 23,  slot 1 */
209 		{ 16+6,  16+6,  16+7,  32+6,  32+7},  /* IdSel 24,  slot 2 */
210 		{ 16+8,  16+8,  16+9,  32+8,  32+9},  /* IdSel 25,  slot 3 */
211 		/* The following 5 are actually on PCI bus 1, which is
212 		   across the built-in bridge of the NORITAKE only.  */
213 		{ 16+1,  16+1,  16+1,  16+1,  16+1},  /* IdSel 16,  QLOGIC */
214 		{ 16+8,  16+8,  16+9,  32+8,  32+9},  /* IdSel 17,  slot 3 */
215 		{16+10, 16+10, 16+11, 32+10, 32+11},  /* IdSel 18,  slot 4 */
216 		{16+12, 16+12, 16+13, 32+12, 32+13},  /* IdSel 19,  slot 5 */
217 		{16+14, 16+14, 16+15, 32+14, 32+15},  /* IdSel 20,  slot 6 */
218 	};
219 	const long min_idsel = 5, max_idsel = 19, irqs_per_slot = 5;
220 	return COMMON_TABLE_LOOKUP;
221 }
222 
223 static u8
224 noritake_swizzle(struct pci_dev *dev, u8 *pinp)
225 {
226 	int slot, pin = *pinp;
227 
228 	if (dev->bus->number == 0) {
229 		slot = PCI_SLOT(dev->devfn);
230 	}
231 	/* Check for the built-in bridge */
232 	else if (PCI_SLOT(dev->bus->self->devfn) == 8) {
233 		slot = PCI_SLOT(dev->devfn) + 15; /* WAG! */
234 	}
235 	else
236 	{
237 		/* Must be a card-based bridge.  */
238 		do {
239 			if (PCI_SLOT(dev->bus->self->devfn) == 8) {
240 				slot = PCI_SLOT(dev->devfn) + 15;
241 				break;
242 			}
243 			pin = pci_swizzle_interrupt_pin(dev, pin);
244 
245 			/* Move up the chain of bridges.  */
246 			dev = dev->bus->self;
247 			/* Slot of the next bridge.  */
248 			slot = PCI_SLOT(dev->devfn);
249 		} while (dev->bus->self);
250 	}
251 	*pinp = pin;
252 	return slot;
253 }
254 
255 struct alpha_machine_vector noritake_primo_mv __initmv = {
256 	.vector_name		= "Noritake-Primo",
257 	DO_EV5_MMU,
258 	DO_DEFAULT_RTC,
259 	DO_CIA_IO,
260 	.machine_check		= cia_machine_check,
261 	.max_isa_dma_address	= ALPHA_MAX_ISA_DMA_ADDRESS,
262 	.min_io_address		= EISA_DEFAULT_IO_BASE,
263 	.min_mem_address	= CIA_DEFAULT_MEM_BASE,
264 
265 	.nr_irqs		= 48,
266 	.device_interrupt	= noritake_device_interrupt,
267 
268 	.init_arch		= cia_init_arch,
269 	.init_irq		= noritake_init_irq,
270 	.init_rtc		= common_init_rtc,
271 	.init_pci		= cia_init_pci,
272 	.kill_arch		= cia_kill_arch,
273 	.pci_map_irq		= noritake_map_irq,
274 	.pci_swizzle		= noritake_swizzle,
275 };
276 ALIAS_MV(noritake_primo)
277