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
56 /*
57 * Atari interrupt handling scheme:
58 * --------------------------------
59 *
60 * All interrupt source have an internal number (defined in
61 * <asm/atariints.h>): Autovector interrupts are 1..7, then follow ST-MFP,
62 * TT-MFP, SCC, and finally VME interrupts. Vector numbers for the latter can
63 * be allocated by atari_register_vme_int().
64 */
65
66 /*
67 * Bitmap for free interrupt vector numbers
68 * (new vectors starting from 0x70 can be allocated by
69 * atari_register_vme_int())
70 */
71 static int free_vme_vec_bitmap;
72
73 /* GK:
74 * HBL IRQ handler for Falcon. Nobody needs it :-)
75 * ++andreas: raise ipl to disable further HBLANK interrupts.
76 */
77 asmlinkage void falcon_hblhandler(void);
78 asm(".text\n"
79 __ALIGN_STR "\n\t"
80 "falcon_hblhandler:\n\t"
81 "orw #0x200,%sp@\n\t" /* set saved ipl to 2 */
82 "rte");
83
84 extern void atari_microwire_cmd(int cmd);
85
atari_irq_startup(struct irq_data * data)86 static unsigned int atari_irq_startup(struct irq_data *data)
87 {
88 unsigned int irq = data->irq;
89
90 m68k_irq_startup(data);
91 atari_turnon_irq(irq);
92 atari_enable_irq(irq);
93 return 0;
94 }
95
atari_irq_shutdown(struct irq_data * data)96 static void atari_irq_shutdown(struct irq_data *data)
97 {
98 unsigned int irq = data->irq;
99
100 atari_disable_irq(irq);
101 atari_turnoff_irq(irq);
102 m68k_irq_shutdown(data);
103
104 if (irq == IRQ_AUTO_4)
105 vectors[VEC_INT4] = falcon_hblhandler;
106 }
107
atari_irq_enable(struct irq_data * data)108 static void atari_irq_enable(struct irq_data *data)
109 {
110 atari_enable_irq(data->irq);
111 }
112
atari_irq_disable(struct irq_data * data)113 static void atari_irq_disable(struct irq_data *data)
114 {
115 atari_disable_irq(data->irq);
116 }
117
118 static struct irq_chip atari_irq_chip = {
119 .name = "atari",
120 .irq_startup = atari_irq_startup,
121 .irq_shutdown = atari_irq_shutdown,
122 .irq_enable = atari_irq_enable,
123 .irq_disable = atari_irq_disable,
124 };
125
126 /*
127 * ST-MFP timer D chained interrupts - each driver gets its own timer
128 * interrupt instance.
129 */
130
131 struct mfptimerbase {
132 volatile struct MFP *mfp;
133 unsigned char mfp_mask, mfp_data;
134 unsigned short int_mask;
135 int handler_irq, mfptimer_irq, server_irq;
136 char *name;
137 } stmfp_base = {
138 .mfp = &st_mfp,
139 .int_mask = 0x0,
140 .handler_irq = IRQ_MFP_TIMD,
141 .mfptimer_irq = IRQ_MFP_TIMER1,
142 .name = "MFP Timer D"
143 };
144
mfp_timer_d_handler(int irq,void * dev_id)145 static irqreturn_t mfp_timer_d_handler(int irq, void *dev_id)
146 {
147 struct mfptimerbase *base = dev_id;
148 int mach_irq;
149 unsigned char ints;
150
151 mach_irq = base->mfptimer_irq;
152 ints = base->int_mask;
153 for (; ints; mach_irq++, ints >>= 1) {
154 if (ints & 1)
155 generic_handle_irq(mach_irq);
156 }
157 return IRQ_HANDLED;
158 }
159
160
atari_mfptimer_enable(struct irq_data * data)161 static void atari_mfptimer_enable(struct irq_data *data)
162 {
163 int mfp_num = data->irq - IRQ_MFP_TIMER1;
164 stmfp_base.int_mask |= 1 << mfp_num;
165 atari_enable_irq(IRQ_MFP_TIMD);
166 }
167
atari_mfptimer_disable(struct irq_data * data)168 static void atari_mfptimer_disable(struct irq_data *data)
169 {
170 int mfp_num = data->irq - IRQ_MFP_TIMER1;
171 stmfp_base.int_mask &= ~(1 << mfp_num);
172 if (!stmfp_base.int_mask)
173 atari_disable_irq(IRQ_MFP_TIMD);
174 }
175
176 static struct irq_chip atari_mfptimer_chip = {
177 .name = "timer_d",
178 .irq_enable = atari_mfptimer_enable,
179 .irq_disable = atari_mfptimer_disable,
180 };
181
182
183 /*
184 * EtherNAT CPLD interrupt handling
185 * CPLD interrupt register is at phys. 0x80000023
186 * Need this mapped in at interrupt startup time
187 * Possibly need this mapped on demand anyway -
188 * EtherNAT USB driver needs to disable IRQ before
189 * startup!
190 */
191
192 static unsigned char *enat_cpld;
193
atari_ethernat_startup(struct irq_data * data)194 static unsigned int atari_ethernat_startup(struct irq_data *data)
195 {
196 int enat_num = 140 - data->irq + 1;
197
198 m68k_irq_startup(data);
199 /*
200 * map CPLD interrupt register
201 */
202 if (!enat_cpld)
203 enat_cpld = (unsigned char *)ioremap((ATARI_ETHERNAT_PHYS_ADDR+0x23), 0x2);
204 /*
205 * do _not_ enable the USB chip interrupt here - causes interrupt storm
206 * and triggers dead interrupt watchdog
207 * Need to reset the USB chip to a sane state in early startup before
208 * removing this hack
209 */
210 if (enat_num == 1)
211 *enat_cpld |= 1 << enat_num;
212
213 return 0;
214 }
215
atari_ethernat_enable(struct irq_data * data)216 static void atari_ethernat_enable(struct irq_data *data)
217 {
218 int enat_num = 140 - data->irq + 1;
219 /*
220 * map CPLD interrupt register
221 */
222 if (!enat_cpld)
223 enat_cpld = (unsigned char *)ioremap((ATARI_ETHERNAT_PHYS_ADDR+0x23), 0x2);
224 *enat_cpld |= 1 << enat_num;
225 }
226
atari_ethernat_disable(struct irq_data * data)227 static void atari_ethernat_disable(struct irq_data *data)
228 {
229 int enat_num = 140 - data->irq + 1;
230 /*
231 * map CPLD interrupt register
232 */
233 if (!enat_cpld)
234 enat_cpld = (unsigned char *)ioremap((ATARI_ETHERNAT_PHYS_ADDR+0x23), 0x2);
235 *enat_cpld &= ~(1 << enat_num);
236 }
237
atari_ethernat_shutdown(struct irq_data * data)238 static void atari_ethernat_shutdown(struct irq_data *data)
239 {
240 int enat_num = 140 - data->irq + 1;
241 if (enat_cpld) {
242 *enat_cpld &= ~(1 << enat_num);
243 iounmap(enat_cpld);
244 enat_cpld = NULL;
245 }
246 }
247
248 static struct irq_chip atari_ethernat_chip = {
249 .name = "ethernat",
250 .irq_startup = atari_ethernat_startup,
251 .irq_shutdown = atari_ethernat_shutdown,
252 .irq_enable = atari_ethernat_enable,
253 .irq_disable = atari_ethernat_disable,
254 };
255
256 /*
257 * void atari_init_IRQ (void)
258 *
259 * Parameters: None
260 *
261 * Returns: Nothing
262 *
263 * This function should be called during kernel startup to initialize
264 * the atari IRQ handling routines.
265 */
266
atari_init_IRQ(void)267 void __init atari_init_IRQ(void)
268 {
269 m68k_setup_user_interrupt(VEC_USER, NUM_ATARI_SOURCES - IRQ_USER);
270 m68k_setup_irq_controller(&atari_irq_chip, handle_simple_irq, 1,
271 NUM_ATARI_SOURCES - 1);
272
273 /* Initialize the MFP(s) */
274
275 #ifdef ATARI_USE_SOFTWARE_EOI
276 st_mfp.vec_adr = 0x48; /* Software EOI-Mode */
277 #else
278 st_mfp.vec_adr = 0x40; /* Automatic EOI-Mode */
279 #endif
280 st_mfp.int_en_a = 0x00; /* turn off MFP-Ints */
281 st_mfp.int_en_b = 0x00;
282 st_mfp.int_mk_a = 0xff; /* no Masking */
283 st_mfp.int_mk_b = 0xff;
284
285 if (ATARIHW_PRESENT(TT_MFP)) {
286 #ifdef ATARI_USE_SOFTWARE_EOI
287 tt_mfp.vec_adr = 0x58; /* Software EOI-Mode */
288 #else
289 tt_mfp.vec_adr = 0x50; /* Automatic EOI-Mode */
290 #endif
291 tt_mfp.int_en_a = 0x00; /* turn off MFP-Ints */
292 tt_mfp.int_en_b = 0x00;
293 tt_mfp.int_mk_a = 0xff; /* no Masking */
294 tt_mfp.int_mk_b = 0xff;
295 }
296
297 if (ATARIHW_PRESENT(SCC) && !atari_SCC_reset_done) {
298 atari_scc.cha_a_ctrl = 9;
299 MFPDELAY();
300 atari_scc.cha_a_ctrl = (char) 0xc0; /* hardware reset */
301 }
302
303 if (ATARIHW_PRESENT(SCU)) {
304 /* init the SCU if present */
305 tt_scu.sys_mask = 0x10; /* enable VBL (for the cursor) and
306 * disable HSYNC interrupts (who
307 * needs them?) MFP and SCC are
308 * enabled in VME mask
309 */
310 tt_scu.vme_mask = 0x60; /* enable MFP and SCC ints */
311 } else {
312 /* If no SCU and no Hades, the HSYNC interrupt needs to be
313 * disabled this way. (Else _inthandler in kernel/sys_call.S
314 * gets overruns)
315 */
316
317 vectors[VEC_INT2] = falcon_hblhandler;
318 vectors[VEC_INT4] = falcon_hblhandler;
319 }
320
321 if (ATARIHW_PRESENT(PCM_8BIT) && ATARIHW_PRESENT(MICROWIRE)) {
322 /* Initialize the LM1992 Sound Controller to enable
323 the PSG sound. This is misplaced here, it should
324 be in an atasound_init(), that doesn't exist yet. */
325 atari_microwire_cmd(MW_LM1992_PSG_HIGH);
326 }
327
328 stdma_init();
329
330 /* Initialize the PSG: all sounds off, both ports output */
331 sound_ym.rd_data_reg_sel = 7;
332 sound_ym.wd_data = 0xff;
333
334 m68k_setup_irq_controller(&atari_mfptimer_chip, handle_simple_irq,
335 IRQ_MFP_TIMER1, 8);
336
337 irq_set_status_flags(IRQ_MFP_TIMER1, IRQ_IS_POLLED);
338 irq_set_status_flags(IRQ_MFP_TIMER2, IRQ_IS_POLLED);
339
340 /* prepare timer D data for use as poll interrupt */
341 /* set Timer D data Register - needs to be > 0 */
342 st_mfp.tim_dt_d = 254; /* < 100 Hz */
343 /* start timer D, div = 1:100 */
344 st_mfp.tim_ct_cd = (st_mfp.tim_ct_cd & 0xf0) | 0x6;
345
346 /* request timer D dispatch handler */
347 if (request_irq(IRQ_MFP_TIMD, mfp_timer_d_handler, IRQF_SHARED,
348 stmfp_base.name, &stmfp_base))
349 pr_err("Couldn't register %s interrupt\n", stmfp_base.name);
350
351 /*
352 * EtherNAT ethernet / USB interrupt handlers
353 */
354
355 m68k_setup_irq_controller(&atari_ethernat_chip, handle_simple_irq,
356 139, 2);
357 }
358
359
360 /*
361 * atari_register_vme_int() returns the number of a free interrupt vector for
362 * hardware with a programmable int vector (probably a VME board).
363 */
364
atari_register_vme_int(void)365 unsigned int atari_register_vme_int(void)
366 {
367 int i;
368
369 for (i = 0; i < 32; i++)
370 if ((free_vme_vec_bitmap & (1 << i)) == 0)
371 break;
372
373 if (i == 16)
374 return 0;
375
376 free_vme_vec_bitmap |= 1 << i;
377 return VME_SOURCE_BASE + i;
378 }
379 EXPORT_SYMBOL(atari_register_vme_int);
380
381
atari_unregister_vme_int(unsigned int irq)382 void atari_unregister_vme_int(unsigned int irq)
383 {
384 if (irq >= VME_SOURCE_BASE && irq < VME_SOURCE_BASE + VME_MAX_SOURCES) {
385 irq -= VME_SOURCE_BASE;
386 free_vme_vec_bitmap &= ~(1 << irq);
387 }
388 }
389 EXPORT_SYMBOL(atari_unregister_vme_int);
390
391
392