1// SPDX-License-Identifier: GPL-2.0
2/*
3 * linux/arch/alpha/kernel/sys_titan.c
4 *
5 * Copyright (C) 1995 David A Rusling
6 * Copyright (C) 1996, 1999 Jay A Estabrook
7 * Copyright (C) 1998, 1999 Richard Henderson
8 * Copyright (C) 1999, 2000 Jeff Wiedemeier
9 *
10 * Code supporting TITAN systems (EV6+TITAN), currently:
11 * Privateer
12 * Falcon
13 * Granite
14 */
15
16#include <linux/kernel.h>
17#include <linux/types.h>
18#include <linux/mm.h>
19#include <linux/sched.h>
20#include <linux/pci.h>
21#include <linux/init.h>
22#include <linux/bitops.h>
23
24#include <asm/ptrace.h>
25#include <asm/dma.h>
26#include <asm/irq.h>
27#include <asm/mmu_context.h>
28#include <asm/io.h>
29#include <asm/core_titan.h>
30#include <asm/hwrpb.h>
31#include <asm/tlbflush.h>
32
33#include "proto.h"
34#include "irq_impl.h"
35#include "pci_impl.h"
36#include "machvec_impl.h"
37#include "err_impl.h"
38
39
40/*
41 * Titan generic
42 */
43
44/*
45 * Titan supports up to 4 CPUs
46 */
47static unsigned long titan_cpu_irq_affinity[4] = { ~0UL, ~0UL, ~0UL, ~0UL };
48
49/*
50 * Mask is set (1) if enabled
51 */
52static unsigned long titan_cached_irq_mask;
53
54/*
55 * Need SMP-safe access to interrupt CSRs
56 */
57DEFINE_SPINLOCK(titan_irq_lock);
58
59static void
60titan_update_irq_hw(unsigned long mask)
61{
62 register titan_cchip *cchip = TITAN_cchip;
63 unsigned long isa_enable = 1UL << 55;
64 register int bcpu = boot_cpuid;
65
66#ifdef CONFIG_SMP
67 cpumask_t cpm;
68 volatile unsigned long *dim0, *dim1, *dim2, *dim3;
69 unsigned long mask0, mask1, mask2, mask3, dummy;
70
71 cpumask_copy(dstp: &cpm, cpu_present_mask);
72 mask &= ~isa_enable;
73 mask0 = mask & titan_cpu_irq_affinity[0];
74 mask1 = mask & titan_cpu_irq_affinity[1];
75 mask2 = mask & titan_cpu_irq_affinity[2];
76 mask3 = mask & titan_cpu_irq_affinity[3];
77
78 if (bcpu == 0) mask0 |= isa_enable;
79 else if (bcpu == 1) mask1 |= isa_enable;
80 else if (bcpu == 2) mask2 |= isa_enable;
81 else mask3 |= isa_enable;
82
83 dim0 = &cchip->dim0.csr;
84 dim1 = &cchip->dim1.csr;
85 dim2 = &cchip->dim2.csr;
86 dim3 = &cchip->dim3.csr;
87 if (!cpumask_test_cpu(cpu: 0, cpumask: &cpm)) dim0 = &dummy;
88 if (!cpumask_test_cpu(cpu: 1, cpumask: &cpm)) dim1 = &dummy;
89 if (!cpumask_test_cpu(cpu: 2, cpumask: &cpm)) dim2 = &dummy;
90 if (!cpumask_test_cpu(cpu: 3, cpumask: &cpm)) dim3 = &dummy;
91
92 *dim0 = mask0;
93 *dim1 = mask1;
94 *dim2 = mask2;
95 *dim3 = mask3;
96 mb();
97 *dim0;
98 *dim1;
99 *dim2;
100 *dim3;
101#else
102 volatile unsigned long *dimB;
103 dimB = &cchip->dim0.csr;
104 if (bcpu == 1) dimB = &cchip->dim1.csr;
105 else if (bcpu == 2) dimB = &cchip->dim2.csr;
106 else if (bcpu == 3) dimB = &cchip->dim3.csr;
107
108 *dimB = mask | isa_enable;
109 mb();
110 *dimB;
111#endif
112}
113
114static inline void
115titan_enable_irq(struct irq_data *d)
116{
117 unsigned int irq = d->irq;
118 spin_lock(lock: &titan_irq_lock);
119 titan_cached_irq_mask |= 1UL << (irq - 16);
120 titan_update_irq_hw(mask: titan_cached_irq_mask);
121 spin_unlock(lock: &titan_irq_lock);
122}
123
124static inline void
125titan_disable_irq(struct irq_data *d)
126{
127 unsigned int irq = d->irq;
128 spin_lock(lock: &titan_irq_lock);
129 titan_cached_irq_mask &= ~(1UL << (irq - 16));
130 titan_update_irq_hw(mask: titan_cached_irq_mask);
131 spin_unlock(lock: &titan_irq_lock);
132}
133
134static void
135titan_cpu_set_irq_affinity(unsigned int irq, cpumask_t affinity)
136{
137 int cpu;
138
139 for (cpu = 0; cpu < 4; cpu++) {
140 if (cpumask_test_cpu(cpu, cpumask: &affinity))
141 titan_cpu_irq_affinity[cpu] |= 1UL << irq;
142 else
143 titan_cpu_irq_affinity[cpu] &= ~(1UL << irq);
144 }
145
146}
147
148static int
149titan_set_irq_affinity(struct irq_data *d, const struct cpumask *affinity,
150 bool force)
151{
152 unsigned int irq = d->irq;
153 spin_lock(lock: &titan_irq_lock);
154 titan_cpu_set_irq_affinity(irq: irq - 16, affinity: *affinity);
155 titan_update_irq_hw(mask: titan_cached_irq_mask);
156 spin_unlock(lock: &titan_irq_lock);
157
158 return 0;
159}
160
161static void
162titan_device_interrupt(unsigned long vector)
163{
164 printk("titan_device_interrupt: NOT IMPLEMENTED YET!!\n");
165}
166
167static void
168titan_srm_device_interrupt(unsigned long vector)
169{
170 int irq;
171
172 irq = (vector - 0x800) >> 4;
173 handle_irq(irq);
174}
175
176
177static void __init
178init_titan_irqs(struct irq_chip * ops, int imin, int imax)
179{
180 long i;
181 for (i = imin; i <= imax; ++i) {
182 irq_set_chip_and_handler(irq: i, chip: ops, handle: handle_level_irq);
183 irq_set_status_flags(irq: i, set: IRQ_LEVEL);
184 }
185}
186
187static struct irq_chip titan_irq_type = {
188 .name = "TITAN",
189 .irq_unmask = titan_enable_irq,
190 .irq_mask = titan_disable_irq,
191 .irq_mask_ack = titan_disable_irq,
192 .irq_set_affinity = titan_set_irq_affinity,
193};
194
195static irqreturn_t
196titan_intr_nop(int irq, void *dev_id)
197{
198 /*
199 * This is a NOP interrupt handler for the purposes of
200 * event counting -- just return.
201 */
202 return IRQ_HANDLED;
203}
204
205static void __init
206titan_init_irq(void)
207{
208 if (alpha_using_srm && !alpha_mv.device_interrupt)
209 alpha_mv.device_interrupt = titan_srm_device_interrupt;
210 if (!alpha_mv.device_interrupt)
211 alpha_mv.device_interrupt = titan_device_interrupt;
212
213 titan_update_irq_hw(mask: 0);
214
215 init_titan_irqs(ops: &titan_irq_type, imin: 16, imax: 63 + 16);
216}
217
218static void __init
219titan_legacy_init_irq(void)
220{
221 /* init the legacy dma controller */
222 outb(value: 0, DMA1_RESET_REG);
223 outb(value: 0, DMA2_RESET_REG);
224 outb(DMA_MODE_CASCADE, DMA2_MODE_REG);
225 outb(value: 0, DMA2_MASK_REG);
226
227 /* init the legacy irq controller */
228 init_i8259a_irqs();
229
230 /* init the titan irqs */
231 titan_init_irq();
232}
233
234void
235titan_dispatch_irqs(u64 mask)
236{
237 unsigned long vector;
238
239 /*
240 * Mask down to those interrupts which are enable on this processor
241 */
242 mask &= titan_cpu_irq_affinity[smp_processor_id()];
243
244 /*
245 * Dispatch all requested interrupts
246 */
247 while (mask) {
248 /* convert to SRM vector... priority is <63> -> <0> */
249 vector = 63 - __kernel_ctlz(mask);
250 mask &= ~(1UL << vector); /* clear it out */
251 vector = 0x900 + (vector << 4); /* convert to SRM vector */
252
253 /* dispatch it */
254 alpha_mv.device_interrupt(vector);
255 }
256}
257
258
259/*
260 * Titan Family
261 */
262static void __init
263titan_request_irq(unsigned int irq, irq_handler_t handler,
264 unsigned long irqflags, const char *devname,
265 void *dev_id)
266{
267 int err;
268 err = request_irq(irq, handler, flags: irqflags, name: devname, dev: dev_id);
269 if (err) {
270 printk("titan_request_irq for IRQ %d returned %d; ignoring\n",
271 irq, err);
272 }
273}
274
275static void __init
276titan_late_init(void)
277{
278 /*
279 * Enable the system error interrupts. These interrupts are
280 * all reported to the kernel as machine checks, so the handler
281 * is a nop so it can be called to count the individual events.
282 */
283 titan_request_irq(irq: 63+16, handler: titan_intr_nop, irqflags: 0,
284 devname: "CChip Error", NULL);
285 titan_request_irq(irq: 62+16, handler: titan_intr_nop, irqflags: 0,
286 devname: "PChip 0 H_Error", NULL);
287 titan_request_irq(irq: 61+16, handler: titan_intr_nop, irqflags: 0,
288 devname: "PChip 1 H_Error", NULL);
289 titan_request_irq(irq: 60+16, handler: titan_intr_nop, irqflags: 0,
290 devname: "PChip 0 C_Error", NULL);
291 titan_request_irq(irq: 59+16, handler: titan_intr_nop, irqflags: 0,
292 devname: "PChip 1 C_Error", NULL);
293
294 /*
295 * Register our error handlers.
296 */
297 titan_register_error_handlers();
298
299 /*
300 * Check if the console left us any error logs.
301 */
302 cdl_check_console_data_log();
303
304}
305
306static int
307titan_map_irq(const struct pci_dev *dev, u8 slot, u8 pin)
308{
309 u8 intline;
310 int irq;
311
312 /* Get the current intline. */
313 pci_read_config_byte(dev, PCI_INTERRUPT_LINE, val: &intline);
314 irq = intline;
315
316 /* Is it explicitly routed through ISA? */
317 if ((irq & 0xF0) == 0xE0)
318 return irq;
319
320 /* Offset by 16 to make room for ISA interrupts 0 - 15. */
321 return irq + 16;
322}
323
324static void __init
325titan_init_pci(void)
326{
327 /*
328 * This isn't really the right place, but there's some init
329 * that needs to be done after everything is basically up.
330 */
331 titan_late_init();
332
333 /* Indicate that we trust the console to configure things properly */
334 pci_set_flags(flags: PCI_PROBE_ONLY);
335 common_init_pci();
336 SMC669_Init(0);
337 locate_and_init_vga(NULL);
338}
339
340
341/*
342 * Privateer
343 */
344static void __init
345privateer_init_pci(void)
346{
347 /*
348 * Hook a couple of extra err interrupts that the
349 * common titan code won't.
350 */
351 titan_request_irq(irq: 53+16, handler: titan_intr_nop, irqflags: 0,
352 devname: "NMI", NULL);
353 titan_request_irq(irq: 50+16, handler: titan_intr_nop, irqflags: 0,
354 devname: "Temperature Warning", NULL);
355
356 /*
357 * Finish with the common version.
358 */
359 return titan_init_pci();
360}
361
362
363/*
364 * The System Vectors.
365 */
366struct alpha_machine_vector titan_mv __initmv = {
367 .vector_name = "TITAN",
368 DO_EV6_MMU,
369 DO_DEFAULT_RTC,
370 DO_TITAN_IO,
371 .machine_check = titan_machine_check,
372 .max_isa_dma_address = ALPHA_MAX_ISA_DMA_ADDRESS,
373 .min_io_address = DEFAULT_IO_BASE,
374 .min_mem_address = DEFAULT_MEM_BASE,
375 .pci_dac_offset = TITAN_DAC_OFFSET,
376
377 .nr_irqs = 80, /* 64 + 16 */
378 /* device_interrupt will be filled in by titan_init_irq */
379
380 .agp_info = titan_agp_info,
381
382 .init_arch = titan_init_arch,
383 .init_irq = titan_legacy_init_irq,
384 .init_rtc = common_init_rtc,
385 .init_pci = titan_init_pci,
386
387 .kill_arch = titan_kill_arch,
388 .pci_map_irq = titan_map_irq,
389 .pci_swizzle = common_swizzle,
390};
391ALIAS_MV(titan)
392
393struct alpha_machine_vector privateer_mv __initmv = {
394 .vector_name = "PRIVATEER",
395 DO_EV6_MMU,
396 DO_DEFAULT_RTC,
397 DO_TITAN_IO,
398 .machine_check = privateer_machine_check,
399 .max_isa_dma_address = ALPHA_MAX_ISA_DMA_ADDRESS,
400 .min_io_address = DEFAULT_IO_BASE,
401 .min_mem_address = DEFAULT_MEM_BASE,
402 .pci_dac_offset = TITAN_DAC_OFFSET,
403
404 .nr_irqs = 80, /* 64 + 16 */
405 /* device_interrupt will be filled in by titan_init_irq */
406
407 .agp_info = titan_agp_info,
408
409 .init_arch = titan_init_arch,
410 .init_irq = titan_legacy_init_irq,
411 .init_rtc = common_init_rtc,
412 .init_pci = privateer_init_pci,
413
414 .kill_arch = titan_kill_arch,
415 .pci_map_irq = titan_map_irq,
416 .pci_swizzle = common_swizzle,
417};
418/* No alpha_mv alias for privateer since we compile it
419 in unconditionally with titan; setup_arch knows how to cope. */
420

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