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 */
71static 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 */
77asmlinkage void falcon_hblhandler(void);
78asm(".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
84extern void atari_microwire_cmd(int cmd);
85
86static 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
96static 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
108static void atari_irq_enable(struct irq_data *data)
109{
110	atari_enable_irq(data->irq);
111}
112
113static void atari_irq_disable(struct irq_data *data)
114{
115	atari_disable_irq(data->irq);
116}
117
118static 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
131struct 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
145static irqreturn_t mfptimer_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
161static 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
168static 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
176static 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
192static unsigned char *enat_cpld;
193
194static 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
216static 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
227static 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
238static 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
248static 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
267void __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, mfptimer_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
365unsigned 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}
379EXPORT_SYMBOL(atari_register_vme_int);
380
381
382void 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}
389EXPORT_SYMBOL(atari_unregister_vme_int);
390
391
392