1// SPDX-License-Identifier: GPL-2.0
2/*
3 * linux/arch/alpha/kernel/sys_sable.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 Sable, Sable-Gamma, and Lynx systems.
10 */
11
12#include <linux/kernel.h>
13#include <linux/types.h>
14#include <linux/mm.h>
15#include <linux/sched.h>
16#include <linux/pci.h>
17#include <linux/init.h>
18
19#include <asm/ptrace.h>
20#include <asm/dma.h>
21#include <asm/irq.h>
22#include <asm/mmu_context.h>
23#include <asm/io.h>
24#include <asm/core_t2.h>
25#include <asm/tlbflush.h>
26
27#include "proto.h"
28#include "irq_impl.h"
29#include "pci_impl.h"
30#include "machvec_impl.h"
31
32DEFINE_SPINLOCK(sable_lynx_irq_lock);
33
34typedef struct irq_swizzle_struct
35{
36 char irq_to_mask[64];
37 char mask_to_irq[64];
38
39 /* Note mask bit is true for DISABLED irqs. */
40 unsigned long shadow_mask;
41
42 void (*update_irq_hw)(unsigned long bit, unsigned long mask);
43 void (*ack_irq_hw)(unsigned long bit);
44
45} irq_swizzle_t;
46
47static irq_swizzle_t *sable_lynx_irq_swizzle;
48
49static void sable_lynx_init_irq(int nr_of_irqs);
50
51#if defined(CONFIG_ALPHA_GENERIC) || defined(CONFIG_ALPHA_SABLE)
52
53/***********************************************************************/
54/*
55 * For SABLE, which is really baroque, we manage 40 IRQ's, but the
56 * hardware really only supports 24, not via normal ISA PIC,
57 * but cascaded custom 8259's, etc.
58 * 0-7 (char at 536)
59 * 8-15 (char at 53a)
60 * 16-23 (char at 53c)
61 *
62 * Summary Registers (536/53a/53c):
63 *
64 * Bit Meaning Kernel IRQ
65 *------------------------------------------
66 * 0 PCI slot 0 34
67 * 1 NCR810 (builtin) 33
68 * 2 TULIP (builtin) 32
69 * 3 mouse 12
70 * 4 PCI slot 1 35
71 * 5 PCI slot 2 36
72 * 6 keyboard 1
73 * 7 floppy 6
74 * 8 COM2 3
75 * 9 parallel port 7
76 *10 EISA irq 3 -
77 *11 EISA irq 4 -
78 *12 EISA irq 5 5
79 *13 EISA irq 6 -
80 *14 EISA irq 7 -
81 *15 COM1 4
82 *16 EISA irq 9 9
83 *17 EISA irq 10 10
84 *18 EISA irq 11 11
85 *19 EISA irq 12 -
86 *20 EISA irq 13 -
87 *21 EISA irq 14 14
88 *22 NC 15
89 *23 IIC -
90 */
91
92static void
93sable_update_irq_hw(unsigned long bit, unsigned long mask)
94{
95 int port = 0x537;
96
97 if (bit >= 16) {
98 port = 0x53d;
99 mask >>= 16;
100 } else if (bit >= 8) {
101 port = 0x53b;
102 mask >>= 8;
103 }
104
105 outb(mask, port);
106}
107
108static void
109sable_ack_irq_hw(unsigned long bit)
110{
111 int port, val1, val2;
112
113 if (bit >= 16) {
114 port = 0x53c;
115 val1 = 0xE0 | (bit - 16);
116 val2 = 0xE0 | 4;
117 } else if (bit >= 8) {
118 port = 0x53a;
119 val1 = 0xE0 | (bit - 8);
120 val2 = 0xE0 | 3;
121 } else {
122 port = 0x536;
123 val1 = 0xE0 | (bit - 0);
124 val2 = 0xE0 | 1;
125 }
126
127 outb(val1, port); /* ack the slave */
128 outb(val2, 0x534); /* ack the master */
129}
130
131static irq_swizzle_t sable_irq_swizzle = {
132 {
133 -1, 6, -1, 8, 15, 12, 7, 9, /* pseudo PIC 0-7 */
134 -1, 16, 17, 18, 3, -1, 21, 22, /* pseudo PIC 8-15 */
135 -1, -1, -1, -1, -1, -1, -1, -1, /* pseudo EISA 0-7 */
136 -1, -1, -1, -1, -1, -1, -1, -1, /* pseudo EISA 8-15 */
137 2, 1, 0, 4, 5, -1, -1, -1, /* pseudo PCI */
138 -1, -1, -1, -1, -1, -1, -1, -1, /* */
139 -1, -1, -1, -1, -1, -1, -1, -1, /* */
140 -1, -1, -1, -1, -1, -1, -1, -1 /* */
141 },
142 {
143 34, 33, 32, 12, 35, 36, 1, 6, /* mask 0-7 */
144 3, 7, -1, -1, 5, -1, -1, 4, /* mask 8-15 */
145 9, 10, 11, -1, -1, 14, 15, -1, /* mask 16-23 */
146 -1, -1, -1, -1, -1, -1, -1, -1, /* */
147 -1, -1, -1, -1, -1, -1, -1, -1, /* */
148 -1, -1, -1, -1, -1, -1, -1, -1, /* */
149 -1, -1, -1, -1, -1, -1, -1, -1, /* */
150 -1, -1, -1, -1, -1, -1, -1, -1 /* */
151 },
152 -1,
153 sable_update_irq_hw,
154 sable_ack_irq_hw
155};
156
157static void __init
158sable_init_irq(void)
159{
160 outb(-1, 0x537); /* slave 0 */
161 outb(-1, 0x53b); /* slave 1 */
162 outb(-1, 0x53d); /* slave 2 */
163 outb(0x44, 0x535); /* enable cascades in master */
164
165 sable_lynx_irq_swizzle = &sable_irq_swizzle;
166 sable_lynx_init_irq(40);
167}
168
169/*
170 * PCI Fixup configuration for ALPHA SABLE (2100).
171 *
172 * The device to slot mapping looks like:
173 *
174 * Slot Device
175 * 0 TULIP
176 * 1 SCSI
177 * 2 PCI-EISA bridge
178 * 3 none
179 * 4 none
180 * 5 none
181 * 6 PCI on board slot 0
182 * 7 PCI on board slot 1
183 * 8 PCI on board slot 2
184 *
185 *
186 * This two layered interrupt approach means that we allocate IRQ 16 and
187 * above for PCI interrupts. The IRQ relates to which bit the interrupt
188 * comes in on. This makes interrupt processing much easier.
189 */
190/*
191 * NOTE: the IRQ assignments below are arbitrary, but need to be consistent
192 * with the values in the irq swizzling tables above.
193 */
194
195static int
196sable_map_irq(const struct pci_dev *dev, u8 slot, u8 pin)
197{
198 static char irq_tab[9][5] = {
199 /*INT INTA INTB INTC INTD */
200 { 32+0, 32+0, 32+0, 32+0, 32+0}, /* IdSel 0, TULIP */
201 { 32+1, 32+1, 32+1, 32+1, 32+1}, /* IdSel 1, SCSI */
202 { -1, -1, -1, -1, -1}, /* IdSel 2, SIO */
203 { -1, -1, -1, -1, -1}, /* IdSel 3, none */
204 { -1, -1, -1, -1, -1}, /* IdSel 4, none */
205 { -1, -1, -1, -1, -1}, /* IdSel 5, none */
206 { 32+2, 32+2, 32+2, 32+2, 32+2}, /* IdSel 6, slot 0 */
207 { 32+3, 32+3, 32+3, 32+3, 32+3}, /* IdSel 7, slot 1 */
208 { 32+4, 32+4, 32+4, 32+4, 32+4} /* IdSel 8, slot 2 */
209 };
210 long min_idsel = 0, max_idsel = 8, irqs_per_slot = 5;
211 return COMMON_TABLE_LOOKUP;
212}
213#endif /* defined(CONFIG_ALPHA_GENERIC) || defined(CONFIG_ALPHA_SABLE) */
214
215/***********************************************************************/
216/* GENERIC irq routines */
217
218static inline void
219sable_lynx_enable_irq(struct irq_data *d)
220{
221 unsigned long bit, mask;
222
223 bit = sable_lynx_irq_swizzle->irq_to_mask[d->irq];
224 spin_lock(lock: &sable_lynx_irq_lock);
225 mask = sable_lynx_irq_swizzle->shadow_mask &= ~(1UL << bit);
226 sable_lynx_irq_swizzle->update_irq_hw(bit, mask);
227 spin_unlock(lock: &sable_lynx_irq_lock);
228#if 0
229 printk("%s: mask 0x%lx bit 0x%lx irq 0x%x\n",
230 __func__, mask, bit, irq);
231#endif
232}
233
234static void
235sable_lynx_disable_irq(struct irq_data *d)
236{
237 unsigned long bit, mask;
238
239 bit = sable_lynx_irq_swizzle->irq_to_mask[d->irq];
240 spin_lock(lock: &sable_lynx_irq_lock);
241 mask = sable_lynx_irq_swizzle->shadow_mask |= 1UL << bit;
242 sable_lynx_irq_swizzle->update_irq_hw(bit, mask);
243 spin_unlock(lock: &sable_lynx_irq_lock);
244#if 0
245 printk("%s: mask 0x%lx bit 0x%lx irq 0x%x\n",
246 __func__, mask, bit, irq);
247#endif
248}
249
250static void
251sable_lynx_mask_and_ack_irq(struct irq_data *d)
252{
253 unsigned long bit, mask;
254
255 bit = sable_lynx_irq_swizzle->irq_to_mask[d->irq];
256 spin_lock(lock: &sable_lynx_irq_lock);
257 mask = sable_lynx_irq_swizzle->shadow_mask |= 1UL << bit;
258 sable_lynx_irq_swizzle->update_irq_hw(bit, mask);
259 sable_lynx_irq_swizzle->ack_irq_hw(bit);
260 spin_unlock(lock: &sable_lynx_irq_lock);
261}
262
263static struct irq_chip sable_lynx_irq_type = {
264 .name = "SABLE/LYNX",
265 .irq_unmask = sable_lynx_enable_irq,
266 .irq_mask = sable_lynx_disable_irq,
267 .irq_mask_ack = sable_lynx_mask_and_ack_irq,
268};
269
270static void
271sable_lynx_srm_device_interrupt(unsigned long vector)
272{
273 /* Note that the vector reported by the SRM PALcode corresponds
274 to the interrupt mask bits, but we have to manage via the
275 so-called legacy IRQs for many common devices. */
276
277 int bit, irq;
278
279 bit = (vector - 0x800) >> 4;
280 irq = sable_lynx_irq_swizzle->mask_to_irq[bit];
281#if 0
282 printk("%s: vector 0x%lx bit 0x%x irq 0x%x\n",
283 __func__, vector, bit, irq);
284#endif
285 handle_irq(irq);
286}
287
288static void __init
289sable_lynx_init_irq(int nr_of_irqs)
290{
291 long i;
292
293 for (i = 0; i < nr_of_irqs; ++i) {
294 irq_set_chip_and_handler(irq: i, chip: &sable_lynx_irq_type,
295 handle: handle_level_irq);
296 irq_set_status_flags(irq: i, set: IRQ_LEVEL);
297 }
298
299 common_init_isa_dma();
300}
301
302static void __init
303sable_lynx_init_pci(void)
304{
305 common_init_pci();
306}
307
308/*****************************************************************/
309/*
310 * The System Vectors
311 *
312 * In order that T2_HAE_ADDRESS should be a constant, we play
313 * these games with GAMMA_BIAS.
314 */
315
316#if defined(CONFIG_ALPHA_GENERIC) || defined(CONFIG_ALPHA_SABLE)
317#undef GAMMA_BIAS
318#define GAMMA_BIAS _GAMMA_BIAS
319struct alpha_machine_vector sable_gamma_mv __initmv = {
320 .vector_name = "Sable-Gamma",
321 DO_EV5_MMU,
322 DO_DEFAULT_RTC,
323 DO_T2_IO,
324 .machine_check = t2_machine_check,
325 .max_isa_dma_address = ALPHA_SABLE_MAX_ISA_DMA_ADDRESS,
326 .min_io_address = EISA_DEFAULT_IO_BASE,
327 .min_mem_address = T2_DEFAULT_MEM_BASE,
328
329 .nr_irqs = 40,
330 .device_interrupt = sable_lynx_srm_device_interrupt,
331
332 .init_arch = t2_init_arch,
333 .init_irq = sable_init_irq,
334 .init_rtc = common_init_rtc,
335 .init_pci = sable_lynx_init_pci,
336 .kill_arch = t2_kill_arch,
337 .pci_map_irq = sable_map_irq,
338 .pci_swizzle = common_swizzle,
339
340 .sys = { .t2 = {
341 .gamma_bias = _GAMMA_BIAS
342 } }
343};
344ALIAS_MV(sable_gamma)
345#endif /* GENERIC || SABLE */
346

source code of linux/arch/alpha/kernel/sys_sable.c