6851abaf5524f6a4b1273339f3c4fb577f59fa2a
[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
17 #include <linux/config.h>
18 #include <linux/kernel.h>
19 #include <linux/init.h>
20 #include <linux/spinlock.h>
21 #include <linux/sched.h>
22 #include <linux/interrupt.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 <asm/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 <asm/arch/gpio.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_IXP2000_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_IXP2000_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_IXP2000_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_IXP2000_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_IXP2000_DEVICE,
108         }, {
109                 .virtual        = IXP2000_PCI_IO_VIRT_BASE,
110                 .pfn            = __phys_to_pfn(IXP2000_PCI_IO_PHYS_BASE),
111                 .length         = IXP2000_PCI_IO_SIZE,
112                 .type           = MT_IXP2000_DEVICE,
113         }, {
114                 .virtual        = IXP2000_PCI_CFG0_VIRT_BASE,
115                 .pfn            = __phys_to_pfn(IXP2000_PCI_CFG0_PHYS_BASE),
116                 .length         = IXP2000_PCI_CFG0_SIZE,
117                 .type           = MT_IXP2000_DEVICE,
118         }, {
119                 .virtual        = IXP2000_PCI_CFG1_VIRT_BASE,
120                 .pfn            = __phys_to_pfn(IXP2000_PCI_CFG1_PHYS_BASE),
121                 .length         = IXP2000_PCI_CFG1_SIZE,
122                 .type           = MT_IXP2000_DEVICE,
123         }
124 };
125
126 void __init ixp2000_map_io(void)
127 {
128         /*
129          * On IXP2400 CPUs we need to use MT_IXP2000_DEVICE so that
130          * XCB=101 (to avoid triggering erratum #66), and given that
131          * this mode speeds up I/O accesses and we have write buffer
132          * flushes in the right places anyway, it doesn't hurt to use
133          * XCB=101 for all IXP2000s.
134          */
135         iotable_init(ixp2000_io_desc, ARRAY_SIZE(ixp2000_io_desc));
136
137         /* Set slowport to 8-bit mode.  */
138         ixp2000_reg_wrb(IXP2000_SLOWPORT_FRM, 1);
139 }
140
141
142 /*************************************************************************
143  * Serial port support for IXP2000
144  *************************************************************************/
145 static struct plat_serial8250_port ixp2000_serial_port[] = {
146         {
147                 .mapbase        = IXP2000_UART_PHYS_BASE,
148                 .membase        = (char *)(IXP2000_UART_VIRT_BASE + 3),
149                 .irq            = IRQ_IXP2000_UART,
150                 .flags          = UPF_BOOT_AUTOCONF | UPF_SKIP_TEST,
151                 .iotype         = UPIO_MEM,
152                 .regshift       = 2,
153                 .uartclk        = 50000000,
154         },
155         { },
156 };
157
158 static struct resource ixp2000_uart_resource = {
159         .start          = IXP2000_UART_PHYS_BASE,
160         .end            = IXP2000_UART_PHYS_BASE + 0x1f,
161         .flags          = IORESOURCE_MEM,
162 };
163
164 static struct platform_device ixp2000_serial_device = {
165         .name           = "serial8250",
166         .id             = PLAT8250_DEV_PLATFORM,
167         .dev            = {
168                 .platform_data          = ixp2000_serial_port,
169         },
170         .num_resources  = 1,
171         .resource       = &ixp2000_uart_resource,
172 };
173
174 void __init ixp2000_uart_init(void)
175 {
176         platform_device_register(&ixp2000_serial_device);
177 }
178
179
180 /*************************************************************************
181  * Timer-tick functions for IXP2000
182  *************************************************************************/
183 static unsigned ticks_per_jiffy;
184 static unsigned ticks_per_usec;
185 static unsigned next_jiffy_time;
186 static volatile unsigned long *missing_jiffy_timer_csr;
187
188 unsigned long ixp2000_gettimeoffset (void)
189 {
190         unsigned long offset;
191
192         offset = next_jiffy_time - *missing_jiffy_timer_csr;
193
194         return offset / ticks_per_usec;
195 }
196
197 static int ixp2000_timer_interrupt(int irq, void *dev_id, struct pt_regs *regs)
198 {
199         write_seqlock(&xtime_lock);
200
201         /* clear timer 1 */
202         ixp2000_reg_wrb(IXP2000_T1_CLR, 1);
203
204         while ((next_jiffy_time - *missing_jiffy_timer_csr) > ticks_per_jiffy) {
205                 timer_tick(regs);
206                 next_jiffy_time -= ticks_per_jiffy;
207         }
208
209         write_sequnlock(&xtime_lock);
210
211         return IRQ_HANDLED;
212 }
213
214 static struct irqaction ixp2000_timer_irq = {
215         .name           = "IXP2000 Timer Tick",
216         .flags          = SA_INTERRUPT | SA_TIMER,
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                 irq_desc[line + IRQ_IXP2000_GPIO0].valid = 0;
282
283                 /* if it's an output, it ain't an interrupt anymore */
284                 GPIO_IRQ_falling_edge &= ~(1 << line);
285                 GPIO_IRQ_rising_edge &= ~(1 << line);
286                 GPIO_IRQ_level_low &= ~(1 << line);
287                 GPIO_IRQ_level_high &= ~(1 << line);
288                 update_gpio_int_csrs();
289
290                 ixp2000_reg_wrb(IXP2000_GPIO_PDSR, 1 << line);
291         } else if (direction == GPIO_IN) {
292                 ixp2000_reg_wrb(IXP2000_GPIO_PDCR, 1 << line);
293         }
294         local_irq_restore(flags);
295 }
296
297
298 /*************************************************************************
299  * IRQ handling IXP2000
300  *************************************************************************/
301 static void ixp2000_GPIO_irq_handler(unsigned int irq, struct irqdesc *desc, struct pt_regs *regs)
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                         desc = irq_desc + i + IRQ_IXP2000_GPIO0;
309                         desc_handle_irq(i + IRQ_IXP2000_GPIO0, desc, regs);
310                 }
311         }
312 }
313
314 static int ixp2000_GPIO_irq_type(unsigned int irq, unsigned int type)
315 {
316         int line = irq - IRQ_IXP2000_GPIO0;
317
318         /*
319          * First, configure this GPIO line as an input.
320          */
321         ixp2000_reg_write(IXP2000_GPIO_PDCR, 1 << line);
322
323         /*
324          * Then, set the proper trigger type.
325          */
326         if (type & IRQT_FALLING)
327                 GPIO_IRQ_falling_edge |= 1 << line;
328         else
329                 GPIO_IRQ_falling_edge &= ~(1 << line);
330         if (type & IRQT_RISING)
331                 GPIO_IRQ_rising_edge |= 1 << line;
332         else
333                 GPIO_IRQ_rising_edge &= ~(1 << line);
334         if (type & IRQT_LOW)
335                 GPIO_IRQ_level_low |= 1 << line;
336         else
337                 GPIO_IRQ_level_low &= ~(1 << line);
338         if (type & IRQT_HIGH)
339                 GPIO_IRQ_level_high |= 1 << line;
340         else
341                 GPIO_IRQ_level_high &= ~(1 << line);
342         update_gpio_int_csrs();
343
344         /*
345          * Finally, mark the corresponding IRQ as valid.
346          */
347         irq_desc[irq].valid = 1;
348
349         return 0;
350 }
351
352 static void ixp2000_GPIO_irq_mask_ack(unsigned int irq)
353 {
354         ixp2000_reg_write(IXP2000_GPIO_INCR, (1 << (irq - IRQ_IXP2000_GPIO0)));
355
356         ixp2000_reg_write(IXP2000_GPIO_EDSR, (1 << (irq - IRQ_IXP2000_GPIO0)));
357         ixp2000_reg_write(IXP2000_GPIO_LDSR, (1 << (irq - IRQ_IXP2000_GPIO0)));
358         ixp2000_reg_wrb(IXP2000_GPIO_INST, (1 << (irq - IRQ_IXP2000_GPIO0)));
359 }
360
361 static void ixp2000_GPIO_irq_mask(unsigned int irq)
362 {
363         ixp2000_reg_wrb(IXP2000_GPIO_INCR, (1 << (irq - IRQ_IXP2000_GPIO0)));
364 }
365
366 static void ixp2000_GPIO_irq_unmask(unsigned int irq)
367 {
368         ixp2000_reg_write(IXP2000_GPIO_INSR, (1 << (irq - IRQ_IXP2000_GPIO0)));
369 }
370
371 static struct irqchip ixp2000_GPIO_irq_chip = {
372         .ack            = ixp2000_GPIO_irq_mask_ack,
373         .mask           = ixp2000_GPIO_irq_mask,
374         .unmask         = ixp2000_GPIO_irq_unmask,
375         .set_type       = ixp2000_GPIO_irq_type,
376 };
377
378 static void ixp2000_pci_irq_mask(unsigned int irq)
379 {
380         unsigned long temp = *IXP2000_PCI_XSCALE_INT_ENABLE;
381         if (irq == IRQ_IXP2000_PCIA)
382                 ixp2000_reg_wrb(IXP2000_PCI_XSCALE_INT_ENABLE, (temp & ~(1 << 26)));
383         else if (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(unsigned int irq)
388 {
389         unsigned long temp = *IXP2000_PCI_XSCALE_INT_ENABLE;
390         if (irq == IRQ_IXP2000_PCIA)
391                 ixp2000_reg_write(IXP2000_PCI_XSCALE_INT_ENABLE, (temp | (1 << 26)));
392         else if (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 irqdesc *desc,  struct pt_regs *regs)
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                         desc = irq_desc + IRQ_IXP2000_DRAM0_MIN_ERR + i;
407                         desc->handle(IRQ_IXP2000_DRAM0_MIN_ERR + i, desc, regs);
408                 }
409         }
410 }
411
412 static void ixp2000_err_irq_mask(unsigned int irq)
413 {
414         ixp2000_reg_write(IXP2000_IRQ_ERR_ENABLE_CLR,
415                         (1 << (irq - IRQ_IXP2000_DRAM0_MIN_ERR)));
416 }
417
418 static void ixp2000_err_irq_unmask(unsigned int irq)
419 {
420         ixp2000_reg_write(IXP2000_IRQ_ERR_ENABLE_SET,
421                         (1 << (irq - IRQ_IXP2000_DRAM0_MIN_ERR)));
422 }
423
424 static struct irqchip ixp2000_err_irq_chip = {
425         .ack    = ixp2000_err_irq_mask,
426         .mask   = ixp2000_err_irq_mask,
427         .unmask = ixp2000_err_irq_unmask
428 };
429
430 static struct irqchip ixp2000_pci_irq_chip = {
431         .ack    = ixp2000_pci_irq_mask,
432         .mask   = ixp2000_pci_irq_mask,
433         .unmask = ixp2000_pci_irq_unmask
434 };
435
436 static void ixp2000_irq_mask(unsigned int irq)
437 {
438         ixp2000_reg_wrb(IXP2000_IRQ_ENABLE_CLR, (1 << irq));
439 }
440
441 static void ixp2000_irq_unmask(unsigned int irq)
442 {
443         ixp2000_reg_write(IXP2000_IRQ_ENABLE_SET, (1 << irq));
444 }
445
446 static struct irqchip ixp2000_irq_chip = {
447         .ack    = ixp2000_irq_mask,
448         .mask   = ixp2000_irq_mask,
449         .unmask = ixp2000_irq_unmask
450 };
451
452 void __init ixp2000_init_irq(void)
453 {
454         int irq;
455
456         /*
457          * Mask all sources
458          */
459         ixp2000_reg_write(IXP2000_IRQ_ENABLE_CLR, 0xffffffff);
460         ixp2000_reg_write(IXP2000_FIQ_ENABLE_CLR, 0xffffffff);
461
462         /* clear all GPIO edge/level detects */
463         ixp2000_reg_write(IXP2000_GPIO_REDR, 0);
464         ixp2000_reg_write(IXP2000_GPIO_FEDR, 0);
465         ixp2000_reg_write(IXP2000_GPIO_LSHR, 0);
466         ixp2000_reg_write(IXP2000_GPIO_LSLR, 0);
467         ixp2000_reg_write(IXP2000_GPIO_INCR, -1);
468
469         /* clear PCI interrupt sources */
470         ixp2000_reg_wrb(IXP2000_PCI_XSCALE_INT_ENABLE, 0);
471
472         /*
473          * Certain bits in the IRQ status register of the 
474          * IXP2000 are reserved. Instead of trying to map
475          * things non 1:1 from bit position to IRQ number,
476          * we mark the reserved IRQs as invalid. This makes
477          * our mask/unmask code much simpler.
478          */
479         for (irq = IRQ_IXP2000_SOFT_INT; irq <= IRQ_IXP2000_THDB3; irq++) {
480                 if ((1 << irq) & IXP2000_VALID_IRQ_MASK) {
481                         set_irq_chip(irq, &ixp2000_irq_chip);
482                         set_irq_handler(irq, do_level_IRQ);
483                         set_irq_flags(irq, IRQF_VALID);
484                 } else set_irq_flags(irq, 0);
485         }
486
487         for (irq = IRQ_IXP2000_DRAM0_MIN_ERR; irq <= IRQ_IXP2000_SP_INT; irq++) {
488                 if((1 << (irq - IRQ_IXP2000_DRAM0_MIN_ERR)) &
489                                 IXP2000_VALID_ERR_IRQ_MASK) {
490                         set_irq_chip(irq, &ixp2000_err_irq_chip);
491                         set_irq_handler(irq, do_level_IRQ);
492                         set_irq_flags(irq, IRQF_VALID);
493                 }
494                 else
495                         set_irq_flags(irq, 0);
496         }
497         set_irq_chained_handler(IRQ_IXP2000_ERRSUM, ixp2000_err_irq_handler);
498
499         /*
500          * GPIO IRQs are invalid until someone sets the interrupt mode
501          * by calling set_irq_type().
502          */
503         for (irq = IRQ_IXP2000_GPIO0; irq <= IRQ_IXP2000_GPIO7; irq++) {
504                 set_irq_chip(irq, &ixp2000_GPIO_irq_chip);
505                 set_irq_handler(irq, do_level_IRQ);
506                 set_irq_flags(irq, 0);
507         }
508         set_irq_chained_handler(IRQ_IXP2000_GPIO, ixp2000_GPIO_irq_handler);
509
510         /*
511          * Enable PCI irqs.  The actual PCI[AB] decoding is done in
512          * entry-macro.S, so we don't need a chained handler for the
513          * PCI interrupt source.
514          */
515         ixp2000_reg_write(IXP2000_IRQ_ENABLE_SET, (1 << IRQ_IXP2000_PCI));
516         for (irq = IRQ_IXP2000_PCIA; irq <= IRQ_IXP2000_PCIB; irq++) {
517                 set_irq_chip(irq, &ixp2000_pci_irq_chip);
518                 set_irq_handler(irq, do_level_IRQ);
519                 set_irq_flags(irq, IRQF_VALID);
520         }
521 }
522