PageRenderTime 27ms CodeModel.GetById 8ms app.highlight 15ms RepoModel.GetById 1ms app.codeStats 0ms

/arch/m68k/mac/oss.c

https://bitbucket.org/evzijst/gittest
C | 301 lines | 201 code | 33 blank | 67 comment | 14 complexity | 46c76b5a5cc3aa5762c1c001cee41b2f MD5 | raw file
  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.
 11 * 990610 (jmt) - Now taking fulll advantage of the OSS. Interrupts are mapped
 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>
 24#include <asm/machw.h>
 25#include <asm/macintosh.h>
 26#include <asm/macints.h>
 27#include <asm/mac_via.h>
 28#include <asm/mac_oss.h>
 29
 30int oss_present;
 31volatile struct mac_oss *oss;
 32
 33irqreturn_t oss_irq(int, void *, struct pt_regs *);
 34irqreturn_t oss_nubus_irq(int, void *, struct pt_regs *);
 35
 36extern irqreturn_t via1_irq(int, void *, struct pt_regs *);
 37extern irqreturn_t mac_scc_dispatch(int, void *, struct pt_regs *);
 38
 39/*
 40 * Initialize the OSS
 41 *
 42 * The OSS "detection" code is actually in via_init() which is always called
 43 * before us. Thus we can count on oss_present being valid on entry.
 44 */
 45
 46void __init oss_init(void)
 47{
 48	int i;
 49
 50	if (!oss_present) return;
 51
 52	oss = (struct mac_oss *) OSS_BASE;
 53
 54	/* Disable all interrupts. Unlike a VIA it looks like we    */
 55	/* do this by setting the source's interrupt level to zero. */
 56
 57	for (i = 0; i <= OSS_NUM_SOURCES; i++) {
 58		oss->irq_level[i] = OSS_IRQLEV_DISABLED;
 59	}
 60	/* If we disable VIA1 here, we never really handle it... */
 61	oss->irq_level[OSS_VIA1] = OSS_IRQLEV_VIA1;
 62}
 63
 64/*
 65 * Register the OSS and NuBus interrupt dispatchers.
 66 */
 67
 68void __init oss_register_interrupts(void)
 69{
 70	cpu_request_irq(OSS_IRQLEV_SCSI, oss_irq, IRQ_FLG_LOCK,
 71			"scsi", (void *) oss);
 72	cpu_request_irq(OSS_IRQLEV_IOPSCC, mac_scc_dispatch, IRQ_FLG_LOCK,
 73			"scc", mac_scc_dispatch);
 74	cpu_request_irq(OSS_IRQLEV_NUBUS, oss_nubus_irq, IRQ_FLG_LOCK,
 75			"nubus", (void *) oss);
 76	cpu_request_irq(OSS_IRQLEV_SOUND, oss_irq, IRQ_FLG_LOCK,
 77			"sound", (void *) oss);
 78	cpu_request_irq(OSS_IRQLEV_VIA1, via1_irq, IRQ_FLG_LOCK,
 79			"via1", (void *) via1);
 80}
 81
 82/*
 83 * Initialize OSS for Nubus access
 84 */
 85
 86void __init oss_nubus_init(void)
 87{
 88}
 89
 90/*
 91 * Handle miscellaneous OSS interrupts. Right now that's just sound
 92 * and SCSI; everything else is routed to its own autovector IRQ.
 93 */
 94
 95irqreturn_t oss_irq(int irq, void *dev_id, struct pt_regs *regs)
 96{
 97	int events;
 98
 99	events = oss->irq_pending & (OSS_IP_SOUND|OSS_IP_SCSI);
100	if (!events)
101		return IRQ_NONE;
102
103#ifdef DEBUG_IRQS
104	if ((console_loglevel == 10) && !(events & OSS_IP_SCSI)) {
105		printk("oss_irq: irq %d events = 0x%04X\n", irq,
106			(int) oss->irq_pending);
107	}
108#endif
109	/* FIXME: how do you clear a pending IRQ?    */
110
111	if (events & OSS_IP_SOUND) {
112		/* FIXME: call sound handler */
113		oss->irq_pending &= ~OSS_IP_SOUND;
114	} else if (events & OSS_IP_SCSI) {
115		oss->irq_level[OSS_SCSI] = OSS_IRQLEV_DISABLED;
116		mac_do_irq_list(IRQ_MAC_SCSI, regs);
117		oss->irq_pending &= ~OSS_IP_SCSI;
118		oss->irq_level[OSS_SCSI] = OSS_IRQLEV_SCSI;
119	} else {
120		/* FIXME: error check here? */
121	}
122	return IRQ_HANDLED;
123}
124
125/*
126 * Nubus IRQ handler, OSS style
127 *
128 * Unlike the VIA/RBV this is on its own autovector interrupt level.
129 */
130
131irqreturn_t oss_nubus_irq(int irq, void *dev_id, struct pt_regs *regs)
132{
133	int events, irq_bit, i;
134
135	events = oss->irq_pending & OSS_IP_NUBUS;
136	if (!events)
137		return IRQ_NONE;
138
139#ifdef DEBUG_NUBUS_INT
140	if (console_loglevel > 7) {
141		printk("oss_nubus_irq: events = 0x%04X\n", events);
142	}
143#endif
144	/* There are only six slots on the OSS, not seven */
145
146	for (i = 0, irq_bit = 1 ; i < 6 ; i++, irq_bit <<= 1) {
147		if (events & irq_bit) {
148			oss->irq_level[i] = OSS_IRQLEV_DISABLED;
149			mac_do_irq_list(NUBUS_SOURCE_BASE + i, regs);
150			oss->irq_pending &= ~irq_bit;
151			oss->irq_level[i] = OSS_IRQLEV_NUBUS;
152		}
153	}
154	return IRQ_HANDLED;
155}
156
157/*
158 * Enable an OSS interrupt
159 *
160 * It looks messy but it's rather straightforward. The switch() statement
161 * just maps the machspec interrupt numbers to the right OSS interrupt
162 * source (if the OSS handles that interrupt) and then sets the interrupt
163 * level for that source to nonzero, thus enabling the interrupt.
164 */
165
166void oss_irq_enable(int irq) {
167#ifdef DEBUG_IRQUSE
168	printk("oss_irq_enable(%d)\n", irq);
169#endif
170	switch(irq) {
171		case IRQ_SCC:
172		case IRQ_SCCA:
173		case IRQ_SCCB:
174			oss->irq_level[OSS_IOPSCC] = OSS_IRQLEV_IOPSCC;
175			break;
176		case IRQ_MAC_ADB:
177			oss->irq_level[OSS_IOPISM] = OSS_IRQLEV_IOPISM;
178			break;
179		case IRQ_MAC_SCSI:
180			oss->irq_level[OSS_SCSI] = OSS_IRQLEV_SCSI;
181			break;
182		case IRQ_NUBUS_9:
183		case IRQ_NUBUS_A:
184		case IRQ_NUBUS_B:
185		case IRQ_NUBUS_C:
186		case IRQ_NUBUS_D:
187		case IRQ_NUBUS_E:
188			irq -= NUBUS_SOURCE_BASE;
189			oss->irq_level[irq] = OSS_IRQLEV_NUBUS;
190			break;
191#ifdef DEBUG_IRQUSE
192		default:
193			printk("%s unknown irq %d\n",__FUNCTION__, irq);
194			break;
195#endif
196	}
197}
198
199/*
200 * Disable an OSS interrupt
201 *
202 * Same as above except we set the source's interrupt level to zero,
203 * to disable the interrupt.
204 */
205
206void oss_irq_disable(int irq) {
207#ifdef DEBUG_IRQUSE
208	printk("oss_irq_disable(%d)\n", irq);
209#endif
210	switch(irq) {
211		case IRQ_SCC:
212		case IRQ_SCCA:
213		case IRQ_SCCB:
214			oss->irq_level[OSS_IOPSCC] = OSS_IRQLEV_DISABLED;
215			break;
216		case IRQ_MAC_ADB:
217			oss->irq_level[OSS_IOPISM] = OSS_IRQLEV_DISABLED;
218			break;
219		case IRQ_MAC_SCSI:
220			oss->irq_level[OSS_SCSI] = OSS_IRQLEV_DISABLED;
221			break;
222		case IRQ_NUBUS_9:
223		case IRQ_NUBUS_A:
224		case IRQ_NUBUS_B:
225		case IRQ_NUBUS_C:
226		case IRQ_NUBUS_D:
227		case IRQ_NUBUS_E:
228			irq -= NUBUS_SOURCE_BASE;
229			oss->irq_level[irq] = OSS_IRQLEV_DISABLED;
230			break;
231#ifdef DEBUG_IRQUSE
232		default:
233			printk("%s unknown irq %d\n", __FUNCTION__, irq);
234			break;
235#endif
236	}
237}
238
239/*
240 * Clear an OSS interrupt
241 *
242 * Not sure if this works or not but it's the only method I could
243 * think of based on the contents of the mac_oss structure.
244 */
245
246void oss_irq_clear(int irq) {
247	/* FIXME: how to do this on OSS? */
248	switch(irq) {
249		case IRQ_SCC:
250		case IRQ_SCCA:
251		case IRQ_SCCB:
252			oss->irq_pending &= ~OSS_IP_IOPSCC;
253			break;
254		case IRQ_MAC_ADB:
255			oss->irq_pending &= ~OSS_IP_IOPISM;
256			break;
257		case IRQ_MAC_SCSI:
258			oss->irq_pending &= ~OSS_IP_SCSI;
259			break;
260		case IRQ_NUBUS_9:
261		case IRQ_NUBUS_A:
262		case IRQ_NUBUS_B:
263		case IRQ_NUBUS_C:
264		case IRQ_NUBUS_D:
265		case IRQ_NUBUS_E:
266			irq -= NUBUS_SOURCE_BASE;
267			oss->irq_pending &= ~(1 << irq);
268			break;
269	}
270}
271
272/*
273 * Check to see if a specific OSS interrupt is pending
274 */
275
276int oss_irq_pending(int irq)
277{
278	switch(irq) {
279		case IRQ_SCC:
280		case IRQ_SCCA:
281		case IRQ_SCCB:
282			return oss->irq_pending & OSS_IP_IOPSCC;
283			break;
284		case IRQ_MAC_ADB:
285			return oss->irq_pending & OSS_IP_IOPISM;
286			break;
287		case IRQ_MAC_SCSI:
288			return oss->irq_pending & OSS_IP_SCSI;
289			break;
290		case IRQ_NUBUS_9:
291		case IRQ_NUBUS_A:
292		case IRQ_NUBUS_B:
293		case IRQ_NUBUS_C:
294		case IRQ_NUBUS_D:
295		case IRQ_NUBUS_E:
296			irq -= NUBUS_SOURCE_BASE;
297			return oss->irq_pending & (1 << irq);
298			break;
299	}
300	return 0;
301}