1 /*
2 * arch/m68k/atari/ataints.c -- Atari Linux interrupt handling code
3 *
4 * 5/2/94 Roman Hodek:
5 * Added support for TT interrupts; setup for TT SCU (may someone has
6 * twiddled there and we won't get the right interrupts :-()
7 *
8 * Major change: The device-independent code in m68k/ints.c didn't know
9 * about non-autovec ints yet. It hardcoded the number of possible ints to
10 * 7 (IRQ1...IRQ7). But the Atari has lots of non-autovec ints! I made the
11 * number of possible ints a constant defined in interrupt.h, which is
12 * 47 for the Atari. So we can call request_irq() for all Atari interrupts
13 * just the normal way. Additionally, all vectors >= 48 are initialized to
14 * call trap() instead of inthandler(). This must be changed here, too.
15 *
16 * 1995-07-16 Lars Brinkhoff <f93labr@dd.chalmers.se>:
17 * Corrected a bug in atari_add_isr() which rejected all SCC
18 * interrupt sources if there were no TT MFP!
19 *
20 * 12/13/95: New interface functions atari_level_triggered_int() and
21 * atari_register_vme_int() as support for level triggered VME interrupts.
22 *
23 * 02/12/96: (Roman)
24 * Total rewrite of Atari interrupt handling, for new scheme see comments
25 * below.
26 *
27 * 1996-09-03 lars brinkhoff <f93labr@dd.chalmers.se>:
28 * Added new function atari_unregister_vme_int(), and
29 * modified atari_register_vme_int() as well as IS_VALID_INTNO()
30 * to work with it.
31 *
32 * This file is subject to the terms and conditions of the GNU General Public
33 * License. See the file COPYING in the main directory of this archive
34 * for more details.
35 *
36 */
37
38 #include <linux/types.h>
39 #include <linux/kernel.h>
40 #include <linux/kernel_stat.h>
41 #include <linux/init.h>
42 #include <linux/seq_file.h>
43 #include <linux/module.h>
44 #include <linux/irq.h>
45
46 #include <asm/traps.h>
47
48 #include <asm/atarihw.h>
49 #include <asm/atariints.h>
50 #include <asm/atari_stdma.h>
51 #include <asm/irq.h>
52 #include <asm/entry.h>
53 #include <asm/io.h>
54
55 #include "atari.h"
56
57 /*
58 * Atari interrupt handling scheme:
59 * --------------------------------
60 *
61 * All interrupt source have an internal number (defined in
62 * <asm/atariints.h>): Autovector interrupts are 1..7, then follow ST-MFP,
63 * TT-MFP, SCC, and finally VME interrupts. Vector numbers for the latter can
64 * be allocated by atari_register_vme_int().
65 */
66
67 /*
68 * Bitmap for free interrupt vector numbers
69 * (new vectors starting from 0x70 can be allocated by
70 * atari_register_vme_int())
71 */
72 static int free_vme_vec_bitmap;
73
74 /* GK:
75 * HBL IRQ handler for Falcon. Nobody needs it :-)
76 * ++andreas: raise ipl to disable further HBLANK interrupts.
77 */
78 asmlinkage void falcon_hblhandler(void);
79 asm(".text\n"
80 __ALIGN_STR "\n\t"
81 "falcon_hblhandler:\n\t"
82 "orw #0x200,%sp@\n\t" /* set saved ipl to 2 */
83 "rte");
84
atari_irq_startup(struct irq_data * data)85 static unsigned int atari_irq_startup(struct irq_data *data)
86 {
87 unsigned int irq = data->irq;
88
89 m68k_irq_startup(data);
90 atari_turnon_irq(irq);
91 atari_enable_irq(irq);
92 return 0;
93 }
94
atari_irq_shutdown(struct irq_data * data)95 static void atari_irq_shutdown(struct irq_data *data)
96 {
97 unsigned int irq = data->irq;
98
99 atari_disable_irq(irq);
100 atari_turnoff_irq(irq);
101 m68k_irq_shutdown(data);
102
103 if (irq == IRQ_AUTO_4)
104 vectors[VEC_INT4] = falcon_hblhandler;
105 }
106
atari_irq_enable(struct irq_data * data)107 static void atari_irq_enable(struct irq_data *data)
108 {
109 atari_enable_irq(data->irq);
110 }
111
atari_irq_disable(struct irq_data * data)112 static void atari_irq_disable(struct irq_data *data)
113 {
114 atari_disable_irq(data->irq);
115 }
116
117 static struct irq_chip atari_irq_chip = {
118 .name = "atari",
119 .irq_startup = atari_irq_startup,
120 .irq_shutdown = atari_irq_shutdown,
121 .irq_enable = atari_irq_enable,
122 .irq_disable = atari_irq_disable,
123 };
124
125 /*
126 * ST-MFP timer D chained interrupts - each driver gets its own timer
127 * interrupt instance.
128 */
129
130 struct mfptimerbase {
131 volatile struct MFP *mfp;
132 unsigned char mfp_mask, mfp_data;
133 unsigned short int_mask;
134 int handler_irq, mfptimer_irq, server_irq;
135 char *name;
136 } stmfp_base = {
137 .mfp = &st_mfp,
138 .int_mask = 0x0,
139 .handler_irq = IRQ_MFP_TIMD,
140 .mfptimer_irq = IRQ_MFP_TIMER1,
141 .name = "MFP Timer D"
142 };
143
mfp_timer_d_handler(int irq,void * dev_id)144 static irqreturn_t mfp_timer_d_handler(int irq, void *dev_id)
145 {
146 struct mfptimerbase *base = dev_id;
147 int mach_irq;
148 unsigned char ints;
149
150 mach_irq = base->mfptimer_irq;
151 ints = base->int_mask;
152 for (; ints; mach_irq++, ints >>= 1) {
153 if (ints & 1)
154 generic_handle_irq(mach_irq);
155 }
156 return IRQ_HANDLED;
157 }
158
159
atari_mfptimer_enable(struct irq_data * data)160 static void atari_mfptimer_enable(struct irq_data *data)
161 {
162 int mfp_num = data->irq - IRQ_MFP_TIMER1;
163 stmfp_base.int_mask |= 1 << mfp_num;
164 atari_enable_irq(IRQ_MFP_TIMD);
165 }
166
atari_mfptimer_disable(struct irq_data * data)167 static void atari_mfptimer_disable(struct irq_data *data)
168 {
169 int mfp_num = data->irq - IRQ_MFP_TIMER1;
170 stmfp_base.int_mask &= ~(1 << mfp_num);
171 if (!stmfp_base.int_mask)
172 atari_disable_irq(IRQ_MFP_TIMD);
173 }
174
175 static struct irq_chip atari_mfptimer_chip = {
176 .name = "timer_d",
177 .irq_enable = atari_mfptimer_enable,
178 .irq_disable = atari_mfptimer_disable,
179 };
180
181
182 /*
183 * EtherNAT CPLD interrupt handling
184 * CPLD interrupt register is at phys. 0x80000023
185 * Need this mapped in at interrupt startup time
186 * Possibly need this mapped on demand anyway -
187 * EtherNAT USB driver needs to disable IRQ before
188 * startup!
189 */
190
191 static unsigned char *enat_cpld;
192
atari_ethernat_startup(struct irq_data * data)193 static unsigned int atari_ethernat_startup(struct irq_data *data)
194 {
195 int enat_num = 140 - data->irq + 1;
196
197 m68k_irq_startup(data);
198 /*
199 * map CPLD interrupt register
200 */
201 if (!enat_cpld)
202 enat_cpld = (unsigned char *)ioremap((ATARI_ETHERNAT_PHYS_ADDR+0x23), 0x2);
203 /*
204 * do _not_ enable the USB chip interrupt here - causes interrupt storm
205 * and triggers dead interrupt watchdog
206 * Need to reset the USB chip to a sane state in early startup before
207 * removing this hack
208 */
209 if (enat_num == 1)
210 *enat_cpld |= 1 << enat_num;
211
212 return 0;
213 }
214
atari_ethernat_enable(struct irq_data * data)215 static void atari_ethernat_enable(struct irq_data *data)
216 {
217 int enat_num = 140 - data->irq + 1;
218 /*
219 * map CPLD interrupt register
220 */
221 if (!enat_cpld)
222 enat_cpld = (unsigned char *)ioremap((ATARI_ETHERNAT_PHYS_ADDR+0x23), 0x2);
223 *enat_cpld |= 1 << enat_num;
224 }
225
atari_ethernat_disable(struct irq_data * data)226 static void atari_ethernat_disable(struct irq_data *data)
227 {
228 int enat_num = 140 - data->irq + 1;
229 /*
230 * map CPLD interrupt register
231 */
232 if (!enat_cpld)
233 enat_cpld = (unsigned char *)ioremap((ATARI_ETHERNAT_PHYS_ADDR+0x23), 0x2);
234 *enat_cpld &= ~(1 << enat_num);
235 }
236
atari_ethernat_shutdown(struct irq_data * data)237 static void atari_ethernat_shutdown(struct irq_data *data)
238 {
239 int enat_num = 140 - data->irq + 1;
240 if (enat_cpld) {
241 *enat_cpld &= ~(1 << enat_num);
242 iounmap(enat_cpld);
243 enat_cpld = NULL;
244 }
245 }
246
247 static struct irq_chip atari_ethernat_chip = {
248 .name = "ethernat",
249 .irq_startup = atari_ethernat_startup,
250 .irq_shutdown = atari_ethernat_shutdown,
251 .irq_enable = atari_ethernat_enable,
252 .irq_disable = atari_ethernat_disable,
253 };
254
255 /*
256 * void atari_init_IRQ (void)
257 *
258 * Parameters: None
259 *
260 * Returns: Nothing
261 *
262 * This function should be called during kernel startup to initialize
263 * the atari IRQ handling routines.
264 */
265
atari_init_IRQ(void)266 void __init atari_init_IRQ(void)
267 {
268 m68k_setup_user_interrupt(VEC_USER, NUM_ATARI_SOURCES - IRQ_USER);
269 m68k_setup_irq_controller(&atari_irq_chip, handle_simple_irq, 1,
270 NUM_ATARI_SOURCES - 1);
271
272 /* Initialize the MFP(s) */
273
274 #ifdef ATARI_USE_SOFTWARE_EOI
275 st_mfp.vec_adr = 0x48; /* Software EOI-Mode */
276 #else
277 st_mfp.vec_adr = 0x40; /* Automatic EOI-Mode */
278 #endif
279 st_mfp.int_en_a = 0x00; /* turn off MFP-Ints */
280 st_mfp.int_en_b = 0x00;
281 st_mfp.int_mk_a = 0xff; /* no Masking */
282 st_mfp.int_mk_b = 0xff;
283
284 if (ATARIHW_PRESENT(TT_MFP)) {
285 #ifdef ATARI_USE_SOFTWARE_EOI
286 tt_mfp.vec_adr = 0x58; /* Software EOI-Mode */
287 #else
288 tt_mfp.vec_adr = 0x50; /* Automatic EOI-Mode */
289 #endif
290 tt_mfp.int_en_a = 0x00; /* turn off MFP-Ints */
291 tt_mfp.int_en_b = 0x00;
292 tt_mfp.int_mk_a = 0xff; /* no Masking */
293 tt_mfp.int_mk_b = 0xff;
294 }
295
296 if (ATARIHW_PRESENT(SCC) && !atari_SCC_reset_done) {
297 atari_scc.cha_a_ctrl = 9;
298 MFPDELAY();
299 atari_scc.cha_a_ctrl = (char) 0xc0; /* hardware reset */
300 }
301
302 if (ATARIHW_PRESENT(SCU)) {
303 /* init the SCU if present */
304 tt_scu.sys_mask = 0x0; /* disable all interrupts */
305 tt_scu.vme_mask = 0x60; /* enable MFP and SCC ints */
306 } else {
307 /* If no SCU and no Hades, the HSYNC interrupt needs to be
308 * disabled this way. (Else _inthandler in kernel/sys_call.S
309 * gets overruns)
310 */
311
312 vectors[VEC_INT2] = falcon_hblhandler;
313 vectors[VEC_INT4] = falcon_hblhandler;
314 }
315
316 if (ATARIHW_PRESENT(PCM_8BIT) && ATARIHW_PRESENT(MICROWIRE)) {
317 /* Initialize the LM1992 Sound Controller to enable
318 the PSG sound. This is misplaced here, it should
319 be in an atasound_init(), that doesn't exist yet. */
320 atari_microwire_cmd(MW_LM1992_PSG_HIGH);
321 }
322
323 stdma_init();
324
325 /* Initialize the PSG: all sounds off, both ports output */
326 sound_ym.rd_data_reg_sel = 7;
327 sound_ym.wd_data = 0xff;
328
329 m68k_setup_irq_controller(&atari_mfptimer_chip, handle_simple_irq,
330 IRQ_MFP_TIMER1, 8);
331
332 irq_set_status_flags(IRQ_MFP_TIMER1, IRQ_IS_POLLED);
333 irq_set_status_flags(IRQ_MFP_TIMER2, IRQ_IS_POLLED);
334
335 /* prepare timer D data for use as poll interrupt */
336 /* set Timer D data Register - needs to be > 0 */
337 st_mfp.tim_dt_d = 254; /* < 100 Hz */
338 /* start timer D, div = 1:100 */
339 st_mfp.tim_ct_cd = (st_mfp.tim_ct_cd & 0xf0) | 0x6;
340
341 /* request timer D dispatch handler */
342 if (request_irq(IRQ_MFP_TIMD, mfp_timer_d_handler, IRQF_SHARED,
343 stmfp_base.name, &stmfp_base))
344 pr_err("Couldn't register %s interrupt\n", stmfp_base.name);
345
346 /*
347 * EtherNAT ethernet / USB interrupt handlers
348 */
349
350 m68k_setup_irq_controller(&atari_ethernat_chip, handle_simple_irq,
351 139, 2);
352 }
353
354
355 /*
356 * atari_register_vme_int() returns the number of a free interrupt vector for
357 * hardware with a programmable int vector (probably a VME board).
358 */
359
atari_register_vme_int(void)360 unsigned int atari_register_vme_int(void)
361 {
362 int i;
363
364 for (i = 0; i < 32; i++)
365 if ((free_vme_vec_bitmap & (1 << i)) == 0)
366 break;
367
368 if (i == 16)
369 return 0;
370
371 free_vme_vec_bitmap |= 1 << i;
372 return VME_SOURCE_BASE + i;
373 }
374 EXPORT_SYMBOL(atari_register_vme_int);
375
376
atari_unregister_vme_int(unsigned int irq)377 void atari_unregister_vme_int(unsigned int irq)
378 {
379 if (irq >= VME_SOURCE_BASE && irq < VME_SOURCE_BASE + VME_MAX_SOURCES) {
380 irq -= VME_SOURCE_BASE;
381 free_vme_vec_bitmap &= ~(1 << irq);
382 }
383 }
384 EXPORT_SYMBOL(atari_unregister_vme_int);
385
386
387