[mirror_ubuntu-bionic-kernel.git] / arch / m68k / mac / oss.c

/*
 *	OSS handling
 *	Written by Joshua M. Thompson (funaho@jurai.org)
 *
 *
 *	This chip is used in the IIfx in place of VIA #2. It acts like a fancy
 *	VIA chip with prorammable interrupt levels.
 *
 * 990502 (jmt) - Major rewrite for new interrupt architecture as well as some
 *		  recent insights into OSS operational details.
 * 990610 (jmt) - Now taking full advantage of the OSS. Interrupts are mapped
 *		  to mostly match the A/UX interrupt scheme supported on the
 *		  VIA side. Also added support for enabling the ISM irq again
 *		  since we now have a functional IOP manager.
 */

#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/delay.h>
#include <linux/init.h>

#include <asm/bootinfo.h>
#include <asm/macintosh.h>
#include <asm/macints.h>
#include <asm/mac_via.h>
#include <asm/mac_oss.h>

int oss_present;
volatile struct mac_oss *oss;

static irqreturn_t oss_irq(int, void *);
static irqreturn_t oss_nubus_irq(int, void *);

extern irqreturn_t via1_irq(int, void *);
extern irqreturn_t mac_scc_dispatch(int, void *);

/*
 * Initialize the OSS
 *
 * The OSS "detection" code is actually in via_init() which is always called
 * before us. Thus we can count on oss_present being valid on entry.
 */

void __init oss_init(void)
{
	int i;

	if (!oss_present) return;

	oss = (struct mac_oss *) OSS_BASE;

	/* Disable all interrupts. Unlike a VIA it looks like we    */
	/* do this by setting the source's interrupt level to zero. */

	for (i = 0; i <= OSS_NUM_SOURCES; i++) {
		oss->irq_level[i] = OSS_IRQLEV_DISABLED;
	}
	/* If we disable VIA1 here, we never really handle it... */
	oss->irq_level[OSS_VIA1] = OSS_IRQLEV_VIA1;
}

/*
 * Register the OSS and NuBus interrupt dispatchers.
 */

void __init oss_register_interrupts(void)
{
	if (request_irq(OSS_IRQLEV_SCSI, oss_irq, IRQ_FLG_LOCK,
			"scsi", (void *) oss))
		pr_err("Couldn't register %s interrupt\n", "scsi");
	if (request_irq(OSS_IRQLEV_IOPSCC, mac_scc_dispatch, IRQ_FLG_LOCK,
			"scc", mac_scc_dispatch))
		pr_err("Couldn't register %s interrupt\n", "scc");
	if (request_irq(OSS_IRQLEV_NUBUS, oss_nubus_irq, IRQ_FLG_LOCK,
			"nubus", (void *) oss))
		pr_err("Couldn't register %s interrupt\n", "nubus");
	if (request_irq(OSS_IRQLEV_SOUND, oss_irq, IRQ_FLG_LOCK,
			"sound", (void *) oss))
		pr_err("Couldn't register %s interrupt\n", "sound");
	if (request_irq(OSS_IRQLEV_VIA1, via1_irq, IRQ_FLG_LOCK,
			"via1", (void *) via1))
		pr_err("Couldn't register %s interrupt\n", "via1");
}

/*
 * Initialize OSS for Nubus access
 */

void __init oss_nubus_init(void)
{
}

/*
 * Handle miscellaneous OSS interrupts. Right now that's just sound
 * and SCSI; everything else is routed to its own autovector IRQ.
 */

static irqreturn_t oss_irq(int irq, void *dev_id)
{
	int events;

	events = oss->irq_pending & (OSS_IP_SOUND|OSS_IP_SCSI);
	if (!events)
		return IRQ_NONE;

#ifdef DEBUG_IRQS
	if ((console_loglevel == 10) && !(events & OSS_IP_SCSI)) {
		printk("oss_irq: irq %d events = 0x%04X\n", irq,
			(int) oss->irq_pending);
	}
#endif
	/* FIXME: how do you clear a pending IRQ?    */

	if (events & OSS_IP_SOUND) {
		oss->irq_pending &= ~OSS_IP_SOUND;
		/* FIXME: call sound handler */
	} else if (events & OSS_IP_SCSI) {
		oss->irq_pending &= ~OSS_IP_SCSI;
		m68k_handle_int(IRQ_MAC_SCSI);
	} else {
		/* FIXME: error check here? */
	}
	return IRQ_HANDLED;
}

/*
 * Nubus IRQ handler, OSS style
 *
 * Unlike the VIA/RBV this is on its own autovector interrupt level.
 */

static irqreturn_t oss_nubus_irq(int irq, void *dev_id)
{
	int events, irq_bit, i;

	events = oss->irq_pending & OSS_IP_NUBUS;
	if (!events)
		return IRQ_NONE;

#ifdef DEBUG_NUBUS_INT
	if (console_loglevel > 7) {
		printk("oss_nubus_irq: events = 0x%04X\n", events);
	}
#endif
	/* There are only six slots on the OSS, not seven */

	i = 6;
	irq_bit = 0x40;
	do {
		--i;
		irq_bit >>= 1;
		if (events & irq_bit) {
			oss->irq_pending &= ~irq_bit;
			m68k_handle_int(NUBUS_SOURCE_BASE + i);
		}
	} while(events & (irq_bit - 1));
	return IRQ_HANDLED;
}

/*
 * Enable an OSS interrupt
 *
 * It looks messy but it's rather straightforward. The switch() statement
 * just maps the machspec interrupt numbers to the right OSS interrupt
 * source (if the OSS handles that interrupt) and then sets the interrupt
 * level for that source to nonzero, thus enabling the interrupt.
 */

void oss_irq_enable(int irq) {
#ifdef DEBUG_IRQUSE
	printk("oss_irq_enable(%d)\n", irq);
#endif
	switch(irq) {
		case IRQ_SCC:
		case IRQ_SCCA:
		case IRQ_SCCB:
			oss->irq_level[OSS_IOPSCC] = OSS_IRQLEV_IOPSCC;
			break;
		case IRQ_MAC_ADB:
			oss->irq_level[OSS_IOPISM] = OSS_IRQLEV_IOPISM;
			break;
		case IRQ_MAC_SCSI:
			oss->irq_level[OSS_SCSI] = OSS_IRQLEV_SCSI;
			break;
		case IRQ_NUBUS_9:
		case IRQ_NUBUS_A:
		case IRQ_NUBUS_B:
		case IRQ_NUBUS_C:
		case IRQ_NUBUS_D:
		case IRQ_NUBUS_E:
			irq -= NUBUS_SOURCE_BASE;
			oss->irq_level[irq] = OSS_IRQLEV_NUBUS;
			break;
#ifdef DEBUG_IRQUSE
		default:
			printk("%s unknown irq %d\n", __func__, irq);
			break;
#endif
	}
}

/*
 * Disable an OSS interrupt
 *
 * Same as above except we set the source's interrupt level to zero,
 * to disable the interrupt.
 */

void oss_irq_disable(int irq) {
#ifdef DEBUG_IRQUSE
	printk("oss_irq_disable(%d)\n", irq);
#endif
	switch(irq) {
		case IRQ_SCC:
		case IRQ_SCCA:
		case IRQ_SCCB:
			oss->irq_level[OSS_IOPSCC] = OSS_IRQLEV_DISABLED;
			break;
		case IRQ_MAC_ADB:
			oss->irq_level[OSS_IOPISM] = OSS_IRQLEV_DISABLED;
			break;
		case IRQ_MAC_SCSI:
			oss->irq_level[OSS_SCSI] = OSS_IRQLEV_DISABLED;
			break;
		case IRQ_NUBUS_9:
		case IRQ_NUBUS_A:
		case IRQ_NUBUS_B:
		case IRQ_NUBUS_C:
		case IRQ_NUBUS_D:
		case IRQ_NUBUS_E:
			irq -= NUBUS_SOURCE_BASE;
			oss->irq_level[irq] = OSS_IRQLEV_DISABLED;
			break;
#ifdef DEBUG_IRQUSE
		default:
			printk("%s unknown irq %d\n", __func__, irq);
			break;
#endif
	}
}

/*
 * Clear an OSS interrupt
 *
 * Not sure if this works or not but it's the only method I could
 * think of based on the contents of the mac_oss structure.
 */

void oss_irq_clear(int irq) {
	/* FIXME: how to do this on OSS? */
	switch(irq) {
		case IRQ_SCC:
		case IRQ_SCCA:
		case IRQ_SCCB:
			oss->irq_pending &= ~OSS_IP_IOPSCC;
			break;
		case IRQ_MAC_ADB:
			oss->irq_pending &= ~OSS_IP_IOPISM;
			break;
		case IRQ_MAC_SCSI:
			oss->irq_pending &= ~OSS_IP_SCSI;
			break;
		case IRQ_NUBUS_9:
		case IRQ_NUBUS_A:
		case IRQ_NUBUS_B:
		case IRQ_NUBUS_C:
		case IRQ_NUBUS_D:
		case IRQ_NUBUS_E:
			irq -= NUBUS_SOURCE_BASE;
			oss->irq_pending &= ~(1 << irq);
			break;
	}
}

/*
 * Check to see if a specific OSS interrupt is pending
 */

int oss_irq_pending(int irq)
{
	switch(irq) {
		case IRQ_SCC:
		case IRQ_SCCA:
		case IRQ_SCCB:
			return oss->irq_pending & OSS_IP_IOPSCC;
			break;
		case IRQ_MAC_ADB:
			return oss->irq_pending & OSS_IP_IOPISM;
			break;
		case IRQ_MAC_SCSI:
			return oss->irq_pending & OSS_IP_SCSI;
			break;
		case IRQ_NUBUS_9:
		case IRQ_NUBUS_A:
		case IRQ_NUBUS_B:
		case IRQ_NUBUS_C:
		case IRQ_NUBUS_D:
		case IRQ_NUBUS_E:
			irq -= NUBUS_SOURCE_BASE;
			return oss->irq_pending & (1 << irq);
			break;
	}
	return 0;
}
Commit	Line	Data
1da177e4 LT	1	/*
	2	* OSS handling
	3	* Written by Joshua M. Thompson (funaho@jurai.org)
	4	*
	5	*
	6	* This chip is used in the IIfx in place of VIA #2. It acts like a fancy
	7	* VIA chip with prorammable interrupt levels.
	8	*
	9	* 990502 (jmt) - Major rewrite for new interrupt architecture as well as some
	10	* recent insights into OSS operational details.
0c79cf6a	11	* 990610 (jmt) - Now taking full advantage of the OSS. Interrupts are mapped
1da177e4 LT	12	* to mostly match the A/UX interrupt scheme supported on the
	13	* VIA side. Also added support for enabling the ISM irq again
	14	* since we now have a functional IOP manager.
	15	*/
	16
	17	#include <linux/types.h>
	18	#include <linux/kernel.h>
	19	#include <linux/mm.h>
	20	#include <linux/delay.h>
	21	#include <linux/init.h>
	22
	23	#include <asm/bootinfo.h>
1da177e4 LT	24	#include <asm/macintosh.h>
	25	#include <asm/macints.h>
	26	#include <asm/mac_via.h>
	27	#include <asm/mac_oss.h>
	28
	29	int oss_present;
	30	volatile struct mac_oss *oss;
	31
8dfbdf4a AB	32	static irqreturn_t oss_irq(int, void *);
8dfbdf4a AB	33	static irqreturn_t oss_nubus_irq(int, void *);
1da177e4	34
2850bc27 AV	35	extern irqreturn_t via1_irq(int, void *);
2850bc27 AV	36	extern irqreturn_t mac_scc_dispatch(int, void *);
1da177e4 LT	37
	38	/*
	39	* Initialize the OSS
	40	*
	41	* The OSS "detection" code is actually in via_init() which is always called
	42	* before us. Thus we can count on oss_present being valid on entry.
	43	*/
	44
	45	void __init oss_init(void)
	46	{
	47	int i;
	48
	49	if (!oss_present) return;
	50
	51	oss = (struct mac_oss *) OSS_BASE;
	52
	53	/* Disable all interrupts. Unlike a VIA it looks like we */
	54	/* do this by setting the source's interrupt level to zero. */
	55
	56	for (i = 0; i <= OSS_NUM_SOURCES; i++) {
	57	oss->irq_level[i] = OSS_IRQLEV_DISABLED;
	58	}
	59	/* If we disable VIA1 here, we never really handle it... */
	60	oss->irq_level[OSS_VIA1] = OSS_IRQLEV_VIA1;
	61	}
	62
	63	/*
	64	* Register the OSS and NuBus interrupt dispatchers.
	65	*/
	66
	67	void __init oss_register_interrupts(void)
	68	{
92c3dd15 GU	69	if (request_irq(OSS_IRQLEV_SCSI, oss_irq, IRQ_FLG_LOCK,
	70	"scsi", (void *) oss))
	71	pr_err("Couldn't register %s interrupt\n", "scsi");
	72	if (request_irq(OSS_IRQLEV_IOPSCC, mac_scc_dispatch, IRQ_FLG_LOCK,
	73	"scc", mac_scc_dispatch))
	74	pr_err("Couldn't register %s interrupt\n", "scc");
	75	if (request_irq(OSS_IRQLEV_NUBUS, oss_nubus_irq, IRQ_FLG_LOCK,
	76	"nubus", (void *) oss))
	77	pr_err("Couldn't register %s interrupt\n", "nubus");
	78	if (request_irq(OSS_IRQLEV_SOUND, oss_irq, IRQ_FLG_LOCK,
	79	"sound", (void *) oss))
	80	pr_err("Couldn't register %s interrupt\n", "sound");
	81	if (request_irq(OSS_IRQLEV_VIA1, via1_irq, IRQ_FLG_LOCK,
	82	"via1", (void *) via1))
	83	pr_err("Couldn't register %s interrupt\n", "via1");
1da177e4 LT	84	}
	85
	86	/*
	87	* Initialize OSS for Nubus access
	88	*/
	89
	90	void __init oss_nubus_init(void)
	91	{
	92	}
	93
	94	/*
	95	* Handle miscellaneous OSS interrupts. Right now that's just sound
	96	* and SCSI; everything else is routed to its own autovector IRQ.
	97	*/
	98
8dfbdf4a	99	static irqreturn_t oss_irq(int irq, void *dev_id)
1da177e4 LT	100	{
	101	int events;
	102
	103	events = oss->irq_pending & (OSS_IP_SOUND\|OSS_IP_SCSI);
	104	if (!events)
	105	return IRQ_NONE;
	106
	107	#ifdef DEBUG_IRQS
	108	if ((console_loglevel == 10) && !(events & OSS_IP_SCSI)) {
	109	printk("oss_irq: irq %d events = 0x%04X\n", irq,
	110	(int) oss->irq_pending);
	111	}
	112	#endif
	113	/* FIXME: how do you clear a pending IRQ? */
	114
	115	if (events & OSS_IP_SOUND) {
1da177e4	116	oss->irq_pending &= ~OSS_IP_SOUND;
647b804c	117	/* FIXME: call sound handler */
1da177e4	118	} else if (events & OSS_IP_SCSI) {
1da177e4	119	oss->irq_pending &= ~OSS_IP_SCSI;
647b804c	120	m68k_handle_int(IRQ_MAC_SCSI);
1da177e4 LT	121	} else {
	122	/* FIXME: error check here? */
	123	}
	124	return IRQ_HANDLED;
	125	}
	126
	127	/*
	128	* Nubus IRQ handler, OSS style
	129	*
	130	* Unlike the VIA/RBV this is on its own autovector interrupt level.
	131	*/
	132
8dfbdf4a	133	static irqreturn_t oss_nubus_irq(int irq, void *dev_id)
1da177e4 LT	134	{
	135	int events, irq_bit, i;
	136
	137	events = oss->irq_pending & OSS_IP_NUBUS;
	138	if (!events)
	139	return IRQ_NONE;
	140
	141	#ifdef DEBUG_NUBUS_INT
	142	if (console_loglevel > 7) {
	143	printk("oss_nubus_irq: events = 0x%04X\n", events);
	144	}
	145	#endif
	146	/* There are only six slots on the OSS, not seven */
	147
67dfb153 FT	148	i = 6;
	149	irq_bit = 0x40;
	150	do {
	151	--i;
	152	irq_bit >>= 1;
1da177e4	153	if (events & irq_bit) {
1da177e4	154	oss->irq_pending &= ~irq_bit;
647b804c	155	m68k_handle_int(NUBUS_SOURCE_BASE + i);
1da177e4	156	}
67dfb153	157	} while(events & (irq_bit - 1));
1da177e4 LT	158	return IRQ_HANDLED;
	159	}
	160
	161	/*
	162	* Enable an OSS interrupt
	163	*
	164	* It looks messy but it's rather straightforward. The switch() statement
	165	* just maps the machspec interrupt numbers to the right OSS interrupt
	166	* source (if the OSS handles that interrupt) and then sets the interrupt
	167	* level for that source to nonzero, thus enabling the interrupt.
	168	*/
	169
	170	void oss_irq_enable(int irq) {
	171	#ifdef DEBUG_IRQUSE
	172	printk("oss_irq_enable(%d)\n", irq);
	173	#endif
	174	switch(irq) {
	175	case IRQ_SCC:
	176	case IRQ_SCCA:
	177	case IRQ_SCCB:
	178	oss->irq_level[OSS_IOPSCC] = OSS_IRQLEV_IOPSCC;
	179	break;
	180	case IRQ_MAC_ADB:
	181	oss->irq_level[OSS_IOPISM] = OSS_IRQLEV_IOPISM;
	182	break;
	183	case IRQ_MAC_SCSI:
	184	oss->irq_level[OSS_SCSI] = OSS_IRQLEV_SCSI;
	185	break;
	186	case IRQ_NUBUS_9:
	187	case IRQ_NUBUS_A:
	188	case IRQ_NUBUS_B:
	189	case IRQ_NUBUS_C:
	190	case IRQ_NUBUS_D:
	191	case IRQ_NUBUS_E:
	192	irq -= NUBUS_SOURCE_BASE;
	193	oss->irq_level[irq] = OSS_IRQLEV_NUBUS;
	194	break;
	195	#ifdef DEBUG_IRQUSE
	196	default:
f85e7cdc	197	printk("%s unknown irq %d\n", __func__, irq);
1da177e4 LT	198	break;
	199	#endif
	200	}
	201	}
	202
	203	/*
	204	* Disable an OSS interrupt
	205	*
	206	* Same as above except we set the source's interrupt level to zero,
	207	* to disable the interrupt.
	208	*/
	209
	210	void oss_irq_disable(int irq) {
	211	#ifdef DEBUG_IRQUSE
	212	printk("oss_irq_disable(%d)\n", irq);
	213	#endif
	214	switch(irq) {
	215	case IRQ_SCC:
	216	case IRQ_SCCA:
	217	case IRQ_SCCB:
	218	oss->irq_level[OSS_IOPSCC] = OSS_IRQLEV_DISABLED;
	219	break;
	220	case IRQ_MAC_ADB:
	221	oss->irq_level[OSS_IOPISM] = OSS_IRQLEV_DISABLED;
	222	break;
	223	case IRQ_MAC_SCSI:
	224	oss->irq_level[OSS_SCSI] = OSS_IRQLEV_DISABLED;
	225	break;
	226	case IRQ_NUBUS_9:
	227	case IRQ_NUBUS_A:
	228	case IRQ_NUBUS_B:
	229	case IRQ_NUBUS_C:
	230	case IRQ_NUBUS_D:
	231	case IRQ_NUBUS_E:
	232	irq -= NUBUS_SOURCE_BASE;
	233	oss->irq_level[irq] = OSS_IRQLEV_DISABLED;
	234	break;
	235	#ifdef DEBUG_IRQUSE
	236	default:
f85e7cdc	237	printk("%s unknown irq %d\n", __func__, irq);
1da177e4 LT	238	break;
	239	#endif
	240	}
	241	}
	242
	243	/*
	244	* Clear an OSS interrupt
	245	*
	246	* Not sure if this works or not but it's the only method I could
	247	* think of based on the contents of the mac_oss structure.
	248	*/
	249
	250	void oss_irq_clear(int irq) {
	251	/* FIXME: how to do this on OSS? */
	252	switch(irq) {
	253	case IRQ_SCC:
	254	case IRQ_SCCA:
	255	case IRQ_SCCB:
	256	oss->irq_pending &= ~OSS_IP_IOPSCC;
	257	break;
	258	case IRQ_MAC_ADB:
	259	oss->irq_pending &= ~OSS_IP_IOPISM;
	260	break;
	261	case IRQ_MAC_SCSI:
	262	oss->irq_pending &= ~OSS_IP_SCSI;
	263	break;
	264	case IRQ_NUBUS_9:
	265	case IRQ_NUBUS_A:
	266	case IRQ_NUBUS_B:
	267	case IRQ_NUBUS_C:
	268	case IRQ_NUBUS_D:
	269	case IRQ_NUBUS_E:
	270	irq -= NUBUS_SOURCE_BASE;
	271	oss->irq_pending &= ~(1 << irq);
	272	break;
	273	}
	274	}
	275
	276	/*
	277	* Check to see if a specific OSS interrupt is pending
	278	*/
	279
	280	int oss_irq_pending(int irq)
	281	{
	282	switch(irq) {
	283	case IRQ_SCC:
	284	case IRQ_SCCA:
	285	case IRQ_SCCB:
	286	return oss->irq_pending & OSS_IP_IOPSCC;
	287	break;
	288	case IRQ_MAC_ADB:
	289	return oss->irq_pending & OSS_IP_IOPISM;
	290	break;
	291	case IRQ_MAC_SCSI:
	292	return oss->irq_pending & OSS_IP_SCSI;
	293	break;
	294	case IRQ_NUBUS_9:
	295	case IRQ_NUBUS_A:
	296	case IRQ_NUBUS_B:
	297	case IRQ_NUBUS_C:
	298	case IRQ_NUBUS_D:
	299	case IRQ_NUBUS_E:
	300	irq -= NUBUS_SOURCE_BASE;
	301	return oss->irq_pending & (1 << irq);
302	break;
303	}
304	return 0;
305	}