Merge git://git.infradead.org/mtd-2.6
[pandora-kernel.git] / arch / arm / mach-ixp2000 / core.c
1 /*
2  * arch/arm/mach-ixp2000/core.c
3  *
4  * Common routines used by all IXP2400/2800 based platforms.
5  *
6  * Author: Deepak Saxena <dsaxena@plexity.net>
7  *
8  * Copyright 2004 (C) MontaVista Software, Inc. 
9  *
10  * Based on work Copyright (C) 2002-2003 Intel Corporation
11  * 
12  * This file is licensed under the terms of the GNU General Public
13  * License version 2. This program is licensed "as is" without any 
14  * warranty of any kind, whether express or implied.
15  */
16 #include <linux/gpio.h>
17 #include <linux/kernel.h>
18 #include <linux/init.h>
19 #include <linux/spinlock.h>
20 #include <linux/sched.h>
21 #include <linux/interrupt.h>
22 #include <linux/irq.h>
23 #include <linux/serial.h>
24 #include <linux/tty.h>
25 #include <linux/bitops.h>
26 #include <linux/serial_8250.h>
27 #include <linux/mm.h>
28 #include <linux/export.h>
29
30 #include <asm/types.h>
31 #include <asm/setup.h>
32 #include <asm/memory.h>
33 #include <mach/hardware.h>
34 #include <asm/irq.h>
35 #include <asm/system.h>
36 #include <asm/tlbflush.h>
37 #include <asm/pgtable.h>
38
39 #include <asm/mach/map.h>
40 #include <asm/mach/time.h>
41 #include <asm/mach/irq.h>
42
43 #include <mach/gpio-ixp2000.h>
44
45 static DEFINE_SPINLOCK(ixp2000_slowport_lock);
46 static unsigned long ixp2000_slowport_irq_flags;
47
48 /*************************************************************************
49  * Slowport access routines
50  *************************************************************************/
51 void ixp2000_acquire_slowport(struct slowport_cfg *new_cfg, struct slowport_cfg *old_cfg)
52 {
53         spin_lock_irqsave(&ixp2000_slowport_lock, ixp2000_slowport_irq_flags);
54
55         old_cfg->CCR = *IXP2000_SLOWPORT_CCR;
56         old_cfg->WTC = *IXP2000_SLOWPORT_WTC2;
57         old_cfg->RTC = *IXP2000_SLOWPORT_RTC2;
58         old_cfg->PCR = *IXP2000_SLOWPORT_PCR;
59         old_cfg->ADC = *IXP2000_SLOWPORT_ADC;
60
61         ixp2000_reg_write(IXP2000_SLOWPORT_CCR, new_cfg->CCR);
62         ixp2000_reg_write(IXP2000_SLOWPORT_WTC2, new_cfg->WTC);
63         ixp2000_reg_write(IXP2000_SLOWPORT_RTC2, new_cfg->RTC);
64         ixp2000_reg_write(IXP2000_SLOWPORT_PCR, new_cfg->PCR);
65         ixp2000_reg_wrb(IXP2000_SLOWPORT_ADC, new_cfg->ADC);
66 }
67
68 void ixp2000_release_slowport(struct slowport_cfg *old_cfg)
69 {
70         ixp2000_reg_write(IXP2000_SLOWPORT_CCR, old_cfg->CCR);
71         ixp2000_reg_write(IXP2000_SLOWPORT_WTC2, old_cfg->WTC);
72         ixp2000_reg_write(IXP2000_SLOWPORT_RTC2, old_cfg->RTC);
73         ixp2000_reg_write(IXP2000_SLOWPORT_PCR, old_cfg->PCR);
74         ixp2000_reg_wrb(IXP2000_SLOWPORT_ADC, old_cfg->ADC);
75
76         spin_unlock_irqrestore(&ixp2000_slowport_lock, 
77                                         ixp2000_slowport_irq_flags);
78 }
79
80 /*************************************************************************
81  * Chip specific mappings shared by all IXP2000 systems
82  *************************************************************************/
83 static struct map_desc ixp2000_io_desc[] __initdata = {
84         {
85                 .virtual        = IXP2000_CAP_VIRT_BASE,
86                 .pfn            = __phys_to_pfn(IXP2000_CAP_PHYS_BASE),
87                 .length         = IXP2000_CAP_SIZE,
88                 .type           = MT_DEVICE,
89         }, {
90                 .virtual        = IXP2000_INTCTL_VIRT_BASE,
91                 .pfn            = __phys_to_pfn(IXP2000_INTCTL_PHYS_BASE),
92                 .length         = IXP2000_INTCTL_SIZE,
93                 .type           = MT_DEVICE,
94         }, {
95                 .virtual        = IXP2000_PCI_CREG_VIRT_BASE,
96                 .pfn            = __phys_to_pfn(IXP2000_PCI_CREG_PHYS_BASE),
97                 .length         = IXP2000_PCI_CREG_SIZE,
98                 .type           = MT_DEVICE,
99         }, {
100                 .virtual        = IXP2000_PCI_CSR_VIRT_BASE,
101                 .pfn            = __phys_to_pfn(IXP2000_PCI_CSR_PHYS_BASE),
102                 .length         = IXP2000_PCI_CSR_SIZE,
103                 .type           = MT_DEVICE,
104         }, {
105                 .virtual        = IXP2000_MSF_VIRT_BASE,
106                 .pfn            = __phys_to_pfn(IXP2000_MSF_PHYS_BASE),
107                 .length         = IXP2000_MSF_SIZE,
108                 .type           = MT_DEVICE,
109         }, {
110                 .virtual        = IXP2000_SCRATCH_RING_VIRT_BASE,
111                 .pfn            = __phys_to_pfn(IXP2000_SCRATCH_RING_PHYS_BASE),
112                 .length         = IXP2000_SCRATCH_RING_SIZE,
113                 .type           = MT_DEVICE,
114         }, {
115                 .virtual        = IXP2000_SRAM0_VIRT_BASE,
116                 .pfn            = __phys_to_pfn(IXP2000_SRAM0_PHYS_BASE),
117                 .length         = IXP2000_SRAM0_SIZE,
118                 .type           = MT_DEVICE,
119         }, {
120                 .virtual        = IXP2000_PCI_IO_VIRT_BASE,
121                 .pfn            = __phys_to_pfn(IXP2000_PCI_IO_PHYS_BASE),
122                 .length         = IXP2000_PCI_IO_SIZE,
123                 .type           = MT_DEVICE,
124         }, {
125                 .virtual        = IXP2000_PCI_CFG0_VIRT_BASE,
126                 .pfn            = __phys_to_pfn(IXP2000_PCI_CFG0_PHYS_BASE),
127                 .length         = IXP2000_PCI_CFG0_SIZE,
128                 .type           = MT_DEVICE,
129         }, {
130                 .virtual        = IXP2000_PCI_CFG1_VIRT_BASE,
131                 .pfn            = __phys_to_pfn(IXP2000_PCI_CFG1_PHYS_BASE),
132                 .length         = IXP2000_PCI_CFG1_SIZE,
133                 .type           = MT_DEVICE,
134         }
135 };
136
137 void __init ixp2000_map_io(void)
138 {
139         iotable_init(ixp2000_io_desc, ARRAY_SIZE(ixp2000_io_desc));
140
141         /* Set slowport to 8-bit mode.  */
142         ixp2000_reg_wrb(IXP2000_SLOWPORT_FRM, 1);
143 }
144
145
146 /*************************************************************************
147  * Serial port support for IXP2000
148  *************************************************************************/
149 static struct plat_serial8250_port ixp2000_serial_port[] = {
150         {
151                 .mapbase        = IXP2000_UART_PHYS_BASE,
152                 .membase        = (char *)(IXP2000_UART_VIRT_BASE + 3),
153                 .irq            = IRQ_IXP2000_UART,
154                 .flags          = UPF_BOOT_AUTOCONF | UPF_SKIP_TEST,
155                 .iotype         = UPIO_MEM,
156                 .regshift       = 2,
157                 .uartclk        = 50000000,
158         },
159         { },
160 };
161
162 static struct resource ixp2000_uart_resource = {
163         .start          = IXP2000_UART_PHYS_BASE,
164         .end            = IXP2000_UART_PHYS_BASE + 0x1f,
165         .flags          = IORESOURCE_MEM,
166 };
167
168 static struct platform_device ixp2000_serial_device = {
169         .name           = "serial8250",
170         .id             = PLAT8250_DEV_PLATFORM,
171         .dev            = {
172                 .platform_data          = ixp2000_serial_port,
173         },
174         .num_resources  = 1,
175         .resource       = &ixp2000_uart_resource,
176 };
177
178 void __init ixp2000_uart_init(void)
179 {
180         platform_device_register(&ixp2000_serial_device);
181 }
182
183
184 /*************************************************************************
185  * Timer-tick functions for IXP2000
186  *************************************************************************/
187 static unsigned ticks_per_jiffy;
188 static unsigned ticks_per_usec;
189 static unsigned next_jiffy_time;
190 static volatile unsigned long *missing_jiffy_timer_csr;
191
192 unsigned long ixp2000_gettimeoffset (void)
193 {
194         unsigned long offset;
195
196         offset = next_jiffy_time - *missing_jiffy_timer_csr;
197
198         return offset / ticks_per_usec;
199 }
200
201 static irqreturn_t ixp2000_timer_interrupt(int irq, void *dev_id)
202 {
203         /* clear timer 1 */
204         ixp2000_reg_wrb(IXP2000_T1_CLR, 1);
205
206         while ((signed long)(next_jiffy_time - *missing_jiffy_timer_csr)
207                                                         >= ticks_per_jiffy) {
208                 timer_tick();
209                 next_jiffy_time -= ticks_per_jiffy;
210         }
211
212         return IRQ_HANDLED;
213 }
214
215 static struct irqaction ixp2000_timer_irq = {
216         .name           = "IXP2000 Timer Tick",
217         .flags          = IRQF_DISABLED | IRQF_TIMER | IRQF_IRQPOLL,
218         .handler        = ixp2000_timer_interrupt,
219 };
220
221 void __init ixp2000_init_time(unsigned long tick_rate)
222 {
223         ticks_per_jiffy = (tick_rate + HZ/2) / HZ;
224         ticks_per_usec = tick_rate / 1000000;
225
226         /*
227          * We use timer 1 as our timer interrupt.
228          */
229         ixp2000_reg_write(IXP2000_T1_CLR, 0);
230         ixp2000_reg_write(IXP2000_T1_CLD, ticks_per_jiffy - 1);
231         ixp2000_reg_write(IXP2000_T1_CTL, (1 << 7));
232
233         /*
234          * We use a second timer as a monotonic counter for tracking
235          * missed jiffies.  The IXP2000 has four timers, but if we're
236          * on an A-step IXP2800, timer 2 and 3 don't work, so on those
237          * chips we use timer 4.  Timer 4 is the only timer that can
238          * be used for the watchdog, so we use timer 2 if we're on a
239          * non-buggy chip.
240          */
241         if ((*IXP2000_PRODUCT_ID & 0x001ffef0) == 0x00000000) {
242                 printk(KERN_INFO "Enabling IXP2800 erratum #25 workaround\n");
243
244                 ixp2000_reg_write(IXP2000_T4_CLR, 0);
245                 ixp2000_reg_write(IXP2000_T4_CLD, -1);
246                 ixp2000_reg_wrb(IXP2000_T4_CTL, (1 << 7));
247                 missing_jiffy_timer_csr = IXP2000_T4_CSR;
248         } else {
249                 ixp2000_reg_write(IXP2000_T2_CLR, 0);
250                 ixp2000_reg_write(IXP2000_T2_CLD, -1);
251                 ixp2000_reg_wrb(IXP2000_T2_CTL, (1 << 7));
252                 missing_jiffy_timer_csr = IXP2000_T2_CSR;
253         }
254         next_jiffy_time = 0xffffffff;
255
256         /* register for interrupt */
257         setup_irq(IRQ_IXP2000_TIMER1, &ixp2000_timer_irq);
258 }
259
260 /*************************************************************************
261  * GPIO helpers
262  *************************************************************************/
263 static unsigned long GPIO_IRQ_falling_edge;
264 static unsigned long GPIO_IRQ_rising_edge;
265 static unsigned long GPIO_IRQ_level_low;
266 static unsigned long GPIO_IRQ_level_high;
267
268 static void update_gpio_int_csrs(void)
269 {
270         ixp2000_reg_write(IXP2000_GPIO_FEDR, GPIO_IRQ_falling_edge);
271         ixp2000_reg_write(IXP2000_GPIO_REDR, GPIO_IRQ_rising_edge);
272         ixp2000_reg_write(IXP2000_GPIO_LSLR, GPIO_IRQ_level_low);
273         ixp2000_reg_wrb(IXP2000_GPIO_LSHR, GPIO_IRQ_level_high);
274 }
275
276 void gpio_line_config(int line, int direction)
277 {
278         unsigned long flags;
279
280         local_irq_save(flags);
281         if (direction == GPIO_OUT) {
282                 /* if it's an output, it ain't an interrupt anymore */
283                 GPIO_IRQ_falling_edge &= ~(1 << line);
284                 GPIO_IRQ_rising_edge &= ~(1 << line);
285                 GPIO_IRQ_level_low &= ~(1 << line);
286                 GPIO_IRQ_level_high &= ~(1 << line);
287                 update_gpio_int_csrs();
288
289                 ixp2000_reg_wrb(IXP2000_GPIO_PDSR, 1 << line);
290         } else if (direction == GPIO_IN) {
291                 ixp2000_reg_wrb(IXP2000_GPIO_PDCR, 1 << line);
292         }
293         local_irq_restore(flags);
294 }
295 EXPORT_SYMBOL(gpio_line_config);
296
297
298 /*************************************************************************
299  * IRQ handling IXP2000
300  *************************************************************************/
301 static void ixp2000_GPIO_irq_handler(unsigned int irq, struct irq_desc *desc)
302 {                               
303         int i;
304         unsigned long status = *IXP2000_GPIO_INST;
305                    
306         for (i = 0; i <= 7; i++) {
307                 if (status & (1<<i)) {
308                         generic_handle_irq(i + IRQ_IXP2000_GPIO0);
309                 }
310         }
311 }
312
313 static int ixp2000_GPIO_irq_type(struct irq_data *d, unsigned int type)
314 {
315         int line = d->irq - IRQ_IXP2000_GPIO0;
316
317         /*
318          * First, configure this GPIO line as an input.
319          */
320         ixp2000_reg_write(IXP2000_GPIO_PDCR, 1 << line);
321
322         /*
323          * Then, set the proper trigger type.
324          */
325         if (type & IRQ_TYPE_EDGE_FALLING)
326                 GPIO_IRQ_falling_edge |= 1 << line;
327         else
328                 GPIO_IRQ_falling_edge &= ~(1 << line);
329         if (type & IRQ_TYPE_EDGE_RISING)
330                 GPIO_IRQ_rising_edge |= 1 << line;
331         else
332                 GPIO_IRQ_rising_edge &= ~(1 << line);
333         if (type & IRQ_TYPE_LEVEL_LOW)
334                 GPIO_IRQ_level_low |= 1 << line;
335         else
336                 GPIO_IRQ_level_low &= ~(1 << line);
337         if (type & IRQ_TYPE_LEVEL_HIGH)
338                 GPIO_IRQ_level_high |= 1 << line;
339         else
340                 GPIO_IRQ_level_high &= ~(1 << line);
341         update_gpio_int_csrs();
342
343         return 0;
344 }
345
346 static void ixp2000_GPIO_irq_mask_ack(struct irq_data *d)
347 {
348         unsigned int irq = d->irq;
349
350         ixp2000_reg_write(IXP2000_GPIO_INCR, (1 << (irq - IRQ_IXP2000_GPIO0)));
351
352         ixp2000_reg_write(IXP2000_GPIO_EDSR, (1 << (irq - IRQ_IXP2000_GPIO0)));
353         ixp2000_reg_write(IXP2000_GPIO_LDSR, (1 << (irq - IRQ_IXP2000_GPIO0)));
354         ixp2000_reg_wrb(IXP2000_GPIO_INST, (1 << (irq - IRQ_IXP2000_GPIO0)));
355 }
356
357 static void ixp2000_GPIO_irq_mask(struct irq_data *d)
358 {
359         unsigned int irq = d->irq;
360
361         ixp2000_reg_wrb(IXP2000_GPIO_INCR, (1 << (irq - IRQ_IXP2000_GPIO0)));
362 }
363
364 static void ixp2000_GPIO_irq_unmask(struct irq_data *d)
365 {
366         unsigned int irq = d->irq;
367
368         ixp2000_reg_write(IXP2000_GPIO_INSR, (1 << (irq - IRQ_IXP2000_GPIO0)));
369 }
370
371 static struct irq_chip ixp2000_GPIO_irq_chip = {
372         .irq_ack        = ixp2000_GPIO_irq_mask_ack,
373         .irq_mask       = ixp2000_GPIO_irq_mask,
374         .irq_unmask     = ixp2000_GPIO_irq_unmask,
375         .irq_set_type   = ixp2000_GPIO_irq_type,
376 };
377
378 static void ixp2000_pci_irq_mask(struct irq_data *d)
379 {
380         unsigned long temp = *IXP2000_PCI_XSCALE_INT_ENABLE;
381         if (d->irq == IRQ_IXP2000_PCIA)
382                 ixp2000_reg_wrb(IXP2000_PCI_XSCALE_INT_ENABLE, (temp & ~(1 << 26)));
383         else if (d->irq == IRQ_IXP2000_PCIB)
384                 ixp2000_reg_wrb(IXP2000_PCI_XSCALE_INT_ENABLE, (temp & ~(1 << 27)));
385 }
386
387 static void ixp2000_pci_irq_unmask(struct irq_data *d)
388 {
389         unsigned long temp = *IXP2000_PCI_XSCALE_INT_ENABLE;
390         if (d->irq == IRQ_IXP2000_PCIA)
391                 ixp2000_reg_write(IXP2000_PCI_XSCALE_INT_ENABLE, (temp | (1 << 26)));
392         else if (d->irq == IRQ_IXP2000_PCIB)
393                 ixp2000_reg_write(IXP2000_PCI_XSCALE_INT_ENABLE, (temp | (1 << 27)));
394 }
395
396 /*
397  * Error interrupts. These are used extensively by the microengine drivers
398  */
399 static void ixp2000_err_irq_handler(unsigned int irq, struct irq_desc *desc)
400 {
401         int i;
402         unsigned long status = *IXP2000_IRQ_ERR_STATUS;
403
404         for(i = 31; i >= 0; i--) {
405                 if(status & (1 << i)) {
406                         generic_handle_irq(IRQ_IXP2000_DRAM0_MIN_ERR + i);
407                 }
408         }
409 }
410
411 static void ixp2000_err_irq_mask(struct irq_data *d)
412 {
413         ixp2000_reg_write(IXP2000_IRQ_ERR_ENABLE_CLR,
414                         (1 << (d->irq - IRQ_IXP2000_DRAM0_MIN_ERR)));
415 }
416
417 static void ixp2000_err_irq_unmask(struct irq_data *d)
418 {
419         ixp2000_reg_write(IXP2000_IRQ_ERR_ENABLE_SET,
420                         (1 << (d->irq - IRQ_IXP2000_DRAM0_MIN_ERR)));
421 }
422
423 static struct irq_chip ixp2000_err_irq_chip = {
424         .irq_ack        = ixp2000_err_irq_mask,
425         .irq_mask       = ixp2000_err_irq_mask,
426         .irq_unmask     = ixp2000_err_irq_unmask
427 };
428
429 static struct irq_chip ixp2000_pci_irq_chip = {
430         .irq_ack        = ixp2000_pci_irq_mask,
431         .irq_mask       = ixp2000_pci_irq_mask,
432         .irq_unmask     = ixp2000_pci_irq_unmask
433 };
434
435 static void ixp2000_irq_mask(struct irq_data *d)
436 {
437         ixp2000_reg_wrb(IXP2000_IRQ_ENABLE_CLR, (1 << d->irq));
438 }
439
440 static void ixp2000_irq_unmask(struct irq_data *d)
441 {
442         ixp2000_reg_write(IXP2000_IRQ_ENABLE_SET, (1 << d->irq));
443 }
444
445 static struct irq_chip ixp2000_irq_chip = {
446         .irq_ack        = ixp2000_irq_mask,
447         .irq_mask       = ixp2000_irq_mask,
448         .irq_unmask     = ixp2000_irq_unmask
449 };
450
451 void __init ixp2000_init_irq(void)
452 {
453         int irq;
454
455         /*
456          * Mask all sources
457          */
458         ixp2000_reg_write(IXP2000_IRQ_ENABLE_CLR, 0xffffffff);
459         ixp2000_reg_write(IXP2000_FIQ_ENABLE_CLR, 0xffffffff);
460
461         /* clear all GPIO edge/level detects */
462         ixp2000_reg_write(IXP2000_GPIO_REDR, 0);
463         ixp2000_reg_write(IXP2000_GPIO_FEDR, 0);
464         ixp2000_reg_write(IXP2000_GPIO_LSHR, 0);
465         ixp2000_reg_write(IXP2000_GPIO_LSLR, 0);
466         ixp2000_reg_write(IXP2000_GPIO_INCR, -1);
467
468         /* clear PCI interrupt sources */
469         ixp2000_reg_wrb(IXP2000_PCI_XSCALE_INT_ENABLE, 0);
470
471         /*
472          * Certain bits in the IRQ status register of the 
473          * IXP2000 are reserved. Instead of trying to map
474          * things non 1:1 from bit position to IRQ number,
475          * we mark the reserved IRQs as invalid. This makes
476          * our mask/unmask code much simpler.
477          */
478         for (irq = IRQ_IXP2000_SOFT_INT; irq <= IRQ_IXP2000_THDB3; irq++) {
479                 if ((1 << irq) & IXP2000_VALID_IRQ_MASK) {
480                         irq_set_chip_and_handler(irq, &ixp2000_irq_chip,
481                                                  handle_level_irq);
482                         set_irq_flags(irq, IRQF_VALID);
483                 } else set_irq_flags(irq, 0);
484         }
485
486         for (irq = IRQ_IXP2000_DRAM0_MIN_ERR; irq <= IRQ_IXP2000_SP_INT; irq++) {
487                 if((1 << (irq - IRQ_IXP2000_DRAM0_MIN_ERR)) &
488                                 IXP2000_VALID_ERR_IRQ_MASK) {
489                         irq_set_chip_and_handler(irq, &ixp2000_err_irq_chip,
490                                                  handle_level_irq);
491                         set_irq_flags(irq, IRQF_VALID);
492                 }
493                 else
494                         set_irq_flags(irq, 0);
495         }
496         irq_set_chained_handler(IRQ_IXP2000_ERRSUM, ixp2000_err_irq_handler);
497
498         for (irq = IRQ_IXP2000_GPIO0; irq <= IRQ_IXP2000_GPIO7; irq++) {
499                 irq_set_chip_and_handler(irq, &ixp2000_GPIO_irq_chip,
500                                          handle_level_irq);
501                 set_irq_flags(irq, IRQF_VALID);
502         }
503         irq_set_chained_handler(IRQ_IXP2000_GPIO, ixp2000_GPIO_irq_handler);
504
505         /*
506          * Enable PCI irqs.  The actual PCI[AB] decoding is done in
507          * entry-macro.S, so we don't need a chained handler for the
508          * PCI interrupt source.
509          */
510         ixp2000_reg_write(IXP2000_IRQ_ENABLE_SET, (1 << IRQ_IXP2000_PCI));
511         for (irq = IRQ_IXP2000_PCIA; irq <= IRQ_IXP2000_PCIB; irq++) {
512                 irq_set_chip_and_handler(irq, &ixp2000_pci_irq_chip,
513                                          handle_level_irq);
514                 set_irq_flags(irq, IRQF_VALID);
515         }
516 }
517