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