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authorPaul Mackerras <paulus@samba.org>2008-01-30 19:25:51 -0500
committerPaul Mackerras <paulus@samba.org>2008-01-30 19:25:51 -0500
commitbd45ac0c5daae35e7c71138172e63df5cf644cf6 (patch)
tree5eb5a599bf6a9d7a8a34e802db932aa9e9555de4 /arch/mips/sni/rm200.c
parent4eece4ccf997c0e6d8fdad3d842e37b16b8d705f (diff)
parent5bdeae46be6dfe9efa44a548bd622af325f4bdb4 (diff)
Merge branch 'linux-2.6'
Diffstat (limited to 'arch/mips/sni/rm200.c')
-rw-r--r--arch/mips/sni/rm200.c326
1 files changed, 314 insertions, 12 deletions
diff --git a/arch/mips/sni/rm200.c b/arch/mips/sni/rm200.c
index 67b061eef6cd..5310aa75afa4 100644
--- a/arch/mips/sni/rm200.c
+++ b/arch/mips/sni/rm200.c
@@ -5,30 +5,36 @@
5 * License. See the file "COPYING" in the main directory of this archive 5 * License. See the file "COPYING" in the main directory of this archive
6 * for more details. 6 * for more details.
7 * 7 *
8 * Copyright (C) 2006 Thomas Bogendoerfer (tsbogend@alpha.franken.de) 8 * Copyright (C) 2006,2007 Thomas Bogendoerfer (tsbogend@alpha.franken.de)
9 *
10 * i8259 parts ripped out of arch/mips/kernel/i8259.c
9 */ 11 */
10 12
13#include <linux/delay.h>
11#include <linux/init.h> 14#include <linux/init.h>
12#include <linux/interrupt.h> 15#include <linux/interrupt.h>
13#include <linux/platform_device.h> 16#include <linux/platform_device.h>
14#include <linux/serial_8250.h> 17#include <linux/serial_8250.h>
18#include <linux/io.h>
15 19
16#include <asm/sni.h> 20#include <asm/sni.h>
17#include <asm/time.h> 21#include <asm/time.h>
18#include <asm/irq_cpu.h> 22#include <asm/irq_cpu.h>
19 23
20#define PORT(_base,_irq) \ 24#define RM200_I8259A_IRQ_BASE 32
25
26#define MEMPORT(_base,_irq) \
21 { \ 27 { \
22 .iobase = _base, \ 28 .mapbase = _base, \
23 .irq = _irq, \ 29 .irq = _irq, \
24 .uartclk = 1843200, \ 30 .uartclk = 1843200, \
25 .iotype = UPIO_PORT, \ 31 .iotype = UPIO_MEM, \
26 .flags = UPF_BOOT_AUTOCONF, \ 32 .flags = UPF_BOOT_AUTOCONF|UPF_IOREMAP, \
27 } 33 }
28 34
29static struct plat_serial8250_port rm200_data[] = { 35static struct plat_serial8250_port rm200_data[] = {
30 PORT(0x3f8, 4), 36 MEMPORT(0x160003f8, RM200_I8259A_IRQ_BASE + 4),
31 PORT(0x2f8, 3), 37 MEMPORT(0x160002f8, RM200_I8259A_IRQ_BASE + 3),
32 { }, 38 { },
33}; 39};
34 40
@@ -112,15 +118,311 @@ static int __init snirm_setup_devinit(void)
112 platform_device_register(&rm200_ds1216_device); 118 platform_device_register(&rm200_ds1216_device);
113 platform_device_register(&snirm_82596_rm200_pdev); 119 platform_device_register(&snirm_82596_rm200_pdev);
114 platform_device_register(&snirm_53c710_rm200_pdev); 120 platform_device_register(&snirm_53c710_rm200_pdev);
121 sni_eisa_root_init();
115 } 122 }
116 return 0; 123 return 0;
117} 124}
118 125
119device_initcall(snirm_setup_devinit); 126device_initcall(snirm_setup_devinit);
120 127
128/*
129 * RM200 has an ISA and an EISA bus. The iSA bus is only used
130 * for onboard devices and also has twi i8259 PICs. Since these
131 * PICs are no accessible via inb/outb the following code uses
132 * readb/writeb to access them
133 */
134
135DEFINE_SPINLOCK(sni_rm200_i8259A_lock);
136#define PIC_CMD 0x00
137#define PIC_IMR 0x01
138#define PIC_ISR PIC_CMD
139#define PIC_POLL PIC_ISR
140#define PIC_OCW3 PIC_ISR
141
142/* i8259A PIC related value */
143#define PIC_CASCADE_IR 2
144#define MASTER_ICW4_DEFAULT 0x01
145#define SLAVE_ICW4_DEFAULT 0x01
146
147/*
148 * This contains the irq mask for both 8259A irq controllers,
149 */
150static unsigned int rm200_cached_irq_mask = 0xffff;
151static __iomem u8 *rm200_pic_master;
152static __iomem u8 *rm200_pic_slave;
153
154#define cached_master_mask (rm200_cached_irq_mask)
155#define cached_slave_mask (rm200_cached_irq_mask >> 8)
156
157static void sni_rm200_disable_8259A_irq(unsigned int irq)
158{
159 unsigned int mask;
160 unsigned long flags;
161
162 irq -= RM200_I8259A_IRQ_BASE;
163 mask = 1 << irq;
164 spin_lock_irqsave(&sni_rm200_i8259A_lock, flags);
165 rm200_cached_irq_mask |= mask;
166 if (irq & 8)
167 writeb(cached_slave_mask, rm200_pic_slave + PIC_IMR);
168 else
169 writeb(cached_master_mask, rm200_pic_master + PIC_IMR);
170 spin_unlock_irqrestore(&sni_rm200_i8259A_lock, flags);
171}
172
173static void sni_rm200_enable_8259A_irq(unsigned int irq)
174{
175 unsigned int mask;
176 unsigned long flags;
177
178 irq -= RM200_I8259A_IRQ_BASE;
179 mask = ~(1 << irq);
180 spin_lock_irqsave(&sni_rm200_i8259A_lock, flags);
181 rm200_cached_irq_mask &= mask;
182 if (irq & 8)
183 writeb(cached_slave_mask, rm200_pic_slave + PIC_IMR);
184 else
185 writeb(cached_master_mask, rm200_pic_master + PIC_IMR);
186 spin_unlock_irqrestore(&sni_rm200_i8259A_lock, flags);
187}
188
189static inline int sni_rm200_i8259A_irq_real(unsigned int irq)
190{
191 int value;
192 int irqmask = 1 << irq;
193
194 if (irq < 8) {
195 writeb(0x0B, rm200_pic_master + PIC_CMD);
196 value = readb(rm200_pic_master + PIC_CMD) & irqmask;
197 writeb(0x0A, rm200_pic_master + PIC_CMD);
198 return value;
199 }
200 writeb(0x0B, rm200_pic_slave + PIC_CMD); /* ISR register */
201 value = readb(rm200_pic_slave + PIC_CMD) & (irqmask >> 8);
202 writeb(0x0A, rm200_pic_slave + PIC_CMD);
203 return value;
204}
205
206/*
207 * Careful! The 8259A is a fragile beast, it pretty
208 * much _has_ to be done exactly like this (mask it
209 * first, _then_ send the EOI, and the order of EOI
210 * to the two 8259s is important!
211 */
212void sni_rm200_mask_and_ack_8259A(unsigned int irq)
213{
214 unsigned int irqmask;
215 unsigned long flags;
216
217 irq -= RM200_I8259A_IRQ_BASE;
218 irqmask = 1 << irq;
219 spin_lock_irqsave(&sni_rm200_i8259A_lock, flags);
220 /*
221 * Lightweight spurious IRQ detection. We do not want
222 * to overdo spurious IRQ handling - it's usually a sign
223 * of hardware problems, so we only do the checks we can
224 * do without slowing down good hardware unnecessarily.
225 *
226 * Note that IRQ7 and IRQ15 (the two spurious IRQs
227 * usually resulting from the 8259A-1|2 PICs) occur
228 * even if the IRQ is masked in the 8259A. Thus we
229 * can check spurious 8259A IRQs without doing the
230 * quite slow i8259A_irq_real() call for every IRQ.
231 * This does not cover 100% of spurious interrupts,
232 * but should be enough to warn the user that there
233 * is something bad going on ...
234 */
235 if (rm200_cached_irq_mask & irqmask)
236 goto spurious_8259A_irq;
237 rm200_cached_irq_mask |= irqmask;
238
239handle_real_irq:
240 if (irq & 8) {
241 readb(rm200_pic_slave + PIC_IMR);
242 writeb(cached_slave_mask, rm200_pic_slave + PIC_IMR);
243 writeb(0x60+(irq & 7), rm200_pic_slave + PIC_CMD);
244 writeb(0x60+PIC_CASCADE_IR, rm200_pic_master + PIC_CMD);
245 } else {
246 readb(rm200_pic_master + PIC_IMR);
247 writeb(cached_master_mask, rm200_pic_master + PIC_IMR);
248 writeb(0x60+irq, rm200_pic_master + PIC_CMD);
249 }
250 spin_unlock_irqrestore(&sni_rm200_i8259A_lock, flags);
251 return;
252
253spurious_8259A_irq:
254 /*
255 * this is the slow path - should happen rarely.
256 */
257 if (sni_rm200_i8259A_irq_real(irq))
258 /*
259 * oops, the IRQ _is_ in service according to the
260 * 8259A - not spurious, go handle it.
261 */
262 goto handle_real_irq;
263
264 {
265 static int spurious_irq_mask;
266 /*
267 * At this point we can be sure the IRQ is spurious,
268 * lets ACK and report it. [once per IRQ]
269 */
270 if (!(spurious_irq_mask & irqmask)) {
271 printk(KERN_DEBUG
272 "spurious RM200 8259A interrupt: IRQ%d.\n", irq);
273 spurious_irq_mask |= irqmask;
274 }
275 atomic_inc(&irq_err_count);
276 /*
277 * Theoretically we do not have to handle this IRQ,
278 * but in Linux this does not cause problems and is
279 * simpler for us.
280 */
281 goto handle_real_irq;
282 }
283}
284
285static struct irq_chip sni_rm200_i8259A_chip = {
286 .name = "RM200-XT-PIC",
287 .mask = sni_rm200_disable_8259A_irq,
288 .unmask = sni_rm200_enable_8259A_irq,
289 .mask_ack = sni_rm200_mask_and_ack_8259A,
290};
291
292/*
293 * Do the traditional i8259 interrupt polling thing. This is for the few
294 * cases where no better interrupt acknowledge method is available and we
295 * absolutely must touch the i8259.
296 */
297static inline int sni_rm200_i8259_irq(void)
298{
299 int irq;
300
301 spin_lock(&sni_rm200_i8259A_lock);
302
303 /* Perform an interrupt acknowledge cycle on controller 1. */
304 writeb(0x0C, rm200_pic_master + PIC_CMD); /* prepare for poll */
305 irq = readb(rm200_pic_master + PIC_CMD) & 7;
306 if (irq == PIC_CASCADE_IR) {
307 /*
308 * Interrupt is cascaded so perform interrupt
309 * acknowledge on controller 2.
310 */
311 writeb(0x0C, rm200_pic_slave + PIC_CMD); /* prepare for poll */
312 irq = (readb(rm200_pic_slave + PIC_CMD) & 7) + 8;
313 }
314
315 if (unlikely(irq == 7)) {
316 /*
317 * This may be a spurious interrupt.
318 *
319 * Read the interrupt status register (ISR). If the most
320 * significant bit is not set then there is no valid
321 * interrupt.
322 */
323 writeb(0x0B, rm200_pic_master + PIC_ISR); /* ISR register */
324 if (~readb(rm200_pic_master + PIC_ISR) & 0x80)
325 irq = -1;
326 }
327
328 spin_unlock(&sni_rm200_i8259A_lock);
329
330 return likely(irq >= 0) ? irq + RM200_I8259A_IRQ_BASE : irq;
331}
332
333void sni_rm200_init_8259A(void)
334{
335 unsigned long flags;
336
337 spin_lock_irqsave(&sni_rm200_i8259A_lock, flags);
338
339 writeb(0xff, rm200_pic_master + PIC_IMR);
340 writeb(0xff, rm200_pic_slave + PIC_IMR);
341
342 writeb(0x11, rm200_pic_master + PIC_CMD);
343 writeb(0, rm200_pic_master + PIC_IMR);
344 writeb(1U << PIC_CASCADE_IR, rm200_pic_master + PIC_IMR);
345 writeb(MASTER_ICW4_DEFAULT, rm200_pic_master + PIC_IMR);
346 writeb(0x11, rm200_pic_slave + PIC_CMD);
347 writeb(8, rm200_pic_slave + PIC_IMR);
348 writeb(PIC_CASCADE_IR, rm200_pic_slave + PIC_IMR);
349 writeb(SLAVE_ICW4_DEFAULT, rm200_pic_slave + PIC_IMR);
350 udelay(100); /* wait for 8259A to initialize */
351
352 writeb(cached_master_mask, rm200_pic_master + PIC_IMR);
353 writeb(cached_slave_mask, rm200_pic_slave + PIC_IMR);
354
355 spin_unlock_irqrestore(&sni_rm200_i8259A_lock, flags);
356}
357
358/*
359 * IRQ2 is cascade interrupt to second interrupt controller
360 */
361static struct irqaction sni_rm200_irq2 = {
362 no_action, 0, CPU_MASK_NONE, "cascade", NULL, NULL
363};
364
365static struct resource sni_rm200_pic1_resource = {
366 .name = "onboard ISA pic1",
367 .start = 0x16000020,
368 .end = 0x16000023,
369 .flags = IORESOURCE_BUSY
370};
371
372static struct resource sni_rm200_pic2_resource = {
373 .name = "onboard ISA pic2",
374 .start = 0x160000a0,
375 .end = 0x160000a3,
376 .flags = IORESOURCE_BUSY
377};
378
379/* ISA irq handler */
380static irqreturn_t sni_rm200_i8259A_irq_handler(int dummy, void *p)
381{
382 int irq;
383
384 irq = sni_rm200_i8259_irq();
385 if (unlikely(irq < 0))
386 return IRQ_NONE;
387
388 do_IRQ(irq);
389 return IRQ_HANDLED;
390}
391
392struct irqaction sni_rm200_i8259A_irq = {
393 .handler = sni_rm200_i8259A_irq_handler,
394 .name = "onboard ISA",
395 .flags = IRQF_SHARED
396};
397
398void __init sni_rm200_i8259_irqs(void)
399{
400 int i;
401
402 rm200_pic_master = ioremap_nocache(0x16000020, 4);
403 if (!rm200_pic_master)
404 return;
405 rm200_pic_slave = ioremap_nocache(0x160000a0, 4);
406 if (!rm200_pic_master) {
407 iounmap(rm200_pic_master);
408 return;
409 }
410
411 insert_resource(&iomem_resource, &sni_rm200_pic1_resource);
412 insert_resource(&iomem_resource, &sni_rm200_pic2_resource);
413
414 sni_rm200_init_8259A();
415
416 for (i = RM200_I8259A_IRQ_BASE; i < RM200_I8259A_IRQ_BASE + 16; i++)
417 set_irq_chip_and_handler(i, &sni_rm200_i8259A_chip,
418 handle_level_irq);
419
420 setup_irq(RM200_I8259A_IRQ_BASE + PIC_CASCADE_IR, &sni_rm200_irq2);
421}
422
121 423
122#define SNI_RM200_INT_STAT_REG 0xbc000000 424#define SNI_RM200_INT_STAT_REG CKSEG1ADDR(0xbc000000)
123#define SNI_RM200_INT_ENA_REG 0xbc080000 425#define SNI_RM200_INT_ENA_REG CKSEG1ADDR(0xbc080000)
124 426
125#define SNI_RM200_INT_START 24 427#define SNI_RM200_INT_START 24
126#define SNI_RM200_INT_END 28 428#define SNI_RM200_INT_END 28
@@ -181,17 +483,17 @@ void __init sni_rm200_irq_init(void)
181 483
182 * (volatile u8 *)SNI_RM200_INT_ENA_REG = 0x1f; 484 * (volatile u8 *)SNI_RM200_INT_ENA_REG = 0x1f;
183 485
486 sni_rm200_i8259_irqs();
184 mips_cpu_irq_init(); 487 mips_cpu_irq_init();
185 /* Actually we've got more interrupts to handle ... */ 488 /* Actually we've got more interrupts to handle ... */
186 for (i = SNI_RM200_INT_START; i <= SNI_RM200_INT_END; i++) 489 for (i = SNI_RM200_INT_START; i <= SNI_RM200_INT_END; i++)
187 set_irq_chip(i, &rm200_irq_type); 490 set_irq_chip(i, &rm200_irq_type);
188 sni_hwint = sni_rm200_hwint; 491 sni_hwint = sni_rm200_hwint;
189 change_c0_status(ST0_IM, IE_IRQ0); 492 change_c0_status(ST0_IM, IE_IRQ0);
190 setup_irq(SNI_RM200_INT_START + 0, &sni_isa_irq); 493 setup_irq(SNI_RM200_INT_START + 0, &sni_rm200_i8259A_irq);
494 setup_irq(SNI_RM200_INT_START + 1, &sni_isa_irq);
191} 495}
192 496
193void __init sni_rm200_init(void) 497void __init sni_rm200_init(void)
194{ 498{
195 set_io_port_base(SNI_PORT_BASE + 0x02000000);
196 ioport_resource.end += 0x02000000;
197} 499}