1 /*
2 * arch/arm/mach-ixp23xx/core.c
3 *
4 * Core routines for IXP23xx chips
5 *
6 * Author: Deepak Saxena <dsaxena@plexity.net>
7 *
8 * Copyright 2005 (c) MontaVista Software, Inc.
9 *
10 * Based on 2.4 code Copyright 2004 (c) 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/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/serial.h>
23 #include <linux/tty.h>
24 #include <linux/bitops.h>
25 #include <linux/serial_8250.h>
26 #include <linux/serial_core.h>
27 #include <linux/device.h>
28 #include <linux/mm.h>
29 #include <linux/time.h>
30 #include <linux/timex.h>
31
32 #include <asm/types.h>
33 #include <asm/setup.h>
34 #include <asm/memory.h>
35 #include <mach/hardware.h>
36 #include <asm/irq.h>
37 #include <asm/system.h>
38 #include <asm/tlbflush.h>
39 #include <asm/pgtable.h>
40
41 #include <asm/mach/map.h>
42 #include <asm/mach/time.h>
43 #include <asm/mach/irq.h>
44 #include <asm/mach/arch.h>
45
46
47 /*************************************************************************
48 * Chip specific mappings shared by all IXP23xx systems
49 *************************************************************************/
50 static struct map_desc ixp23xx_io_desc[] __initdata = {
51 { /* XSI-CPP CSRs */
52 .virtual = IXP23XX_XSI2CPP_CSR_VIRT,
53 .pfn = __phys_to_pfn(IXP23XX_XSI2CPP_CSR_PHYS),
54 .length = IXP23XX_XSI2CPP_CSR_SIZE,
55 .type = MT_DEVICE,
56 }, { /* Expansion Bus Config */
57 .virtual = IXP23XX_EXP_CFG_VIRT,
58 .pfn = __phys_to_pfn(IXP23XX_EXP_CFG_PHYS),
59 .length = IXP23XX_EXP_CFG_SIZE,
60 .type = MT_DEVICE,
61 }, { /* UART, Interrupt ctrl, GPIO, timers, NPEs, MACS,.... */
62 .virtual = IXP23XX_PERIPHERAL_VIRT,
63 .pfn = __phys_to_pfn(IXP23XX_PERIPHERAL_PHYS),
64 .length = IXP23XX_PERIPHERAL_SIZE,
65 .type = MT_DEVICE,
66 }, { /* CAP CSRs */
67 .virtual = IXP23XX_CAP_CSR_VIRT,
68 .pfn = __phys_to_pfn(IXP23XX_CAP_CSR_PHYS),
69 .length = IXP23XX_CAP_CSR_SIZE,
70 .type = MT_DEVICE,
71 }, { /* MSF CSRs */
72 .virtual = IXP23XX_MSF_CSR_VIRT,
73 .pfn = __phys_to_pfn(IXP23XX_MSF_CSR_PHYS),
74 .length = IXP23XX_MSF_CSR_SIZE,
75 .type = MT_DEVICE,
76 }, { /* PCI I/O Space */
77 .virtual = IXP23XX_PCI_IO_VIRT,
78 .pfn = __phys_to_pfn(IXP23XX_PCI_IO_PHYS),
79 .length = IXP23XX_PCI_IO_SIZE,
80 .type = MT_DEVICE,
81 }, { /* PCI Config Space */
82 .virtual = IXP23XX_PCI_CFG_VIRT,
83 .pfn = __phys_to_pfn(IXP23XX_PCI_CFG_PHYS),
84 .length = IXP23XX_PCI_CFG_SIZE,
85 .type = MT_DEVICE,
86 }, { /* PCI local CFG CSRs */
87 .virtual = IXP23XX_PCI_CREG_VIRT,
88 .pfn = __phys_to_pfn(IXP23XX_PCI_CREG_PHYS),
89 .length = IXP23XX_PCI_CREG_SIZE,
90 .type = MT_DEVICE,
91 }, { /* PCI MEM Space */
92 .virtual = IXP23XX_PCI_MEM_VIRT,
93 .pfn = __phys_to_pfn(IXP23XX_PCI_MEM_PHYS),
94 .length = IXP23XX_PCI_MEM_SIZE,
95 .type = MT_DEVICE,
96 }
97 };
98
ixp23xx_map_io(void)99 void __init ixp23xx_map_io(void)
100 {
101 iotable_init(ixp23xx_io_desc, ARRAY_SIZE(ixp23xx_io_desc));
102 }
103
104
105 /***************************************************************************
106 * IXP23xx Interrupt Handling
107 ***************************************************************************/
108 enum ixp23xx_irq_type {
109 IXP23XX_IRQ_LEVEL, IXP23XX_IRQ_EDGE
110 };
111
112 static void ixp23xx_config_irq(unsigned int, enum ixp23xx_irq_type);
113
ixp23xx_irq_set_type(unsigned int irq,unsigned int type)114 static int ixp23xx_irq_set_type(unsigned int irq, unsigned int type)
115 {
116 int line = irq - IRQ_IXP23XX_GPIO6 + 6;
117 u32 int_style;
118 enum ixp23xx_irq_type irq_type;
119 volatile u32 *int_reg;
120
121 /*
122 * Only GPIOs 6-15 are wired to interrupts on IXP23xx
123 */
124 if (line < 6 || line > 15)
125 return -EINVAL;
126
127 switch (type) {
128 case IRQ_TYPE_EDGE_BOTH:
129 int_style = IXP23XX_GPIO_STYLE_TRANSITIONAL;
130 irq_type = IXP23XX_IRQ_EDGE;
131 break;
132 case IRQ_TYPE_EDGE_RISING:
133 int_style = IXP23XX_GPIO_STYLE_RISING_EDGE;
134 irq_type = IXP23XX_IRQ_EDGE;
135 break;
136 case IRQ_TYPE_EDGE_FALLING:
137 int_style = IXP23XX_GPIO_STYLE_FALLING_EDGE;
138 irq_type = IXP23XX_IRQ_EDGE;
139 break;
140 case IRQ_TYPE_LEVEL_HIGH:
141 int_style = IXP23XX_GPIO_STYLE_ACTIVE_HIGH;
142 irq_type = IXP23XX_IRQ_LEVEL;
143 break;
144 case IRQ_TYPE_LEVEL_LOW:
145 int_style = IXP23XX_GPIO_STYLE_ACTIVE_LOW;
146 irq_type = IXP23XX_IRQ_LEVEL;
147 break;
148 default:
149 return -EINVAL;
150 }
151
152 ixp23xx_config_irq(irq, irq_type);
153
154 if (line >= 8) { /* pins 8-15 */
155 line -= 8;
156 int_reg = (volatile u32 *)IXP23XX_GPIO_GPIT2R;
157 } else { /* pins 0-7 */
158 int_reg = (volatile u32 *)IXP23XX_GPIO_GPIT1R;
159 }
160
161 /*
162 * Clear pending interrupts
163 */
164 *IXP23XX_GPIO_GPISR = (1 << line);
165
166 /* Clear the style for the appropriate pin */
167 *int_reg &= ~(IXP23XX_GPIO_STYLE_MASK <<
168 (line * IXP23XX_GPIO_STYLE_SIZE));
169
170 /* Set the new style */
171 *int_reg |= (int_style << (line * IXP23XX_GPIO_STYLE_SIZE));
172
173 return 0;
174 }
175
ixp23xx_irq_mask(unsigned int irq)176 static void ixp23xx_irq_mask(unsigned int irq)
177 {
178 volatile unsigned long *intr_reg;
179
180 if (irq >= 56)
181 irq += 8;
182
183 intr_reg = IXP23XX_INTR_EN1 + (irq / 32);
184 *intr_reg &= ~(1 << (irq % 32));
185 }
186
ixp23xx_irq_ack(unsigned int irq)187 static void ixp23xx_irq_ack(unsigned int irq)
188 {
189 int line = irq - IRQ_IXP23XX_GPIO6 + 6;
190
191 if ((line < 6) || (line > 15))
192 return;
193
194 *IXP23XX_GPIO_GPISR = (1 << line);
195 }
196
197 /*
198 * Level triggered interrupts on GPIO lines can only be cleared when the
199 * interrupt condition disappears.
200 */
ixp23xx_irq_level_unmask(unsigned int irq)201 static void ixp23xx_irq_level_unmask(unsigned int irq)
202 {
203 volatile unsigned long *intr_reg;
204
205 ixp23xx_irq_ack(irq);
206
207 if (irq >= 56)
208 irq += 8;
209
210 intr_reg = IXP23XX_INTR_EN1 + (irq / 32);
211 *intr_reg |= (1 << (irq % 32));
212 }
213
ixp23xx_irq_edge_unmask(unsigned int irq)214 static void ixp23xx_irq_edge_unmask(unsigned int irq)
215 {
216 volatile unsigned long *intr_reg;
217
218 if (irq >= 56)
219 irq += 8;
220
221 intr_reg = IXP23XX_INTR_EN1 + (irq / 32);
222 *intr_reg |= (1 << (irq % 32));
223 }
224
225 static struct irq_chip ixp23xx_irq_level_chip = {
226 .ack = ixp23xx_irq_mask,
227 .mask = ixp23xx_irq_mask,
228 .unmask = ixp23xx_irq_level_unmask,
229 .set_type = ixp23xx_irq_set_type
230 };
231
232 static struct irq_chip ixp23xx_irq_edge_chip = {
233 .ack = ixp23xx_irq_ack,
234 .mask = ixp23xx_irq_mask,
235 .unmask = ixp23xx_irq_edge_unmask,
236 .set_type = ixp23xx_irq_set_type
237 };
238
ixp23xx_pci_irq_mask(unsigned int irq)239 static void ixp23xx_pci_irq_mask(unsigned int irq)
240 {
241 *IXP23XX_PCI_XSCALE_INT_ENABLE &= ~(1 << (IRQ_IXP23XX_INTA + 27 - irq));
242 }
243
ixp23xx_pci_irq_unmask(unsigned int irq)244 static void ixp23xx_pci_irq_unmask(unsigned int irq)
245 {
246 *IXP23XX_PCI_XSCALE_INT_ENABLE |= (1 << (IRQ_IXP23XX_INTA + 27 - irq));
247 }
248
249 /*
250 * TODO: Should this just be done at ASM level?
251 */
pci_handler(unsigned int irq,struct irq_desc * desc)252 static void pci_handler(unsigned int irq, struct irq_desc *desc)
253 {
254 u32 pci_interrupt;
255 unsigned int irqno;
256
257 pci_interrupt = *IXP23XX_PCI_XSCALE_INT_STATUS;
258
259 desc->chip->ack(irq);
260
261 /* See which PCI_INTA, or PCI_INTB interrupted */
262 if (pci_interrupt & (1 << 26)) {
263 irqno = IRQ_IXP23XX_INTB;
264 } else if (pci_interrupt & (1 << 27)) {
265 irqno = IRQ_IXP23XX_INTA;
266 } else {
267 BUG();
268 }
269
270 generic_handle_irq(irqno);
271
272 desc->chip->unmask(irq);
273 }
274
275 static struct irq_chip ixp23xx_pci_irq_chip = {
276 .ack = ixp23xx_pci_irq_mask,
277 .mask = ixp23xx_pci_irq_mask,
278 .unmask = ixp23xx_pci_irq_unmask
279 };
280
ixp23xx_config_irq(unsigned int irq,enum ixp23xx_irq_type type)281 static void ixp23xx_config_irq(unsigned int irq, enum ixp23xx_irq_type type)
282 {
283 switch (type) {
284 case IXP23XX_IRQ_LEVEL:
285 set_irq_chip(irq, &ixp23xx_irq_level_chip);
286 set_irq_handler(irq, handle_level_irq);
287 break;
288 case IXP23XX_IRQ_EDGE:
289 set_irq_chip(irq, &ixp23xx_irq_edge_chip);
290 set_irq_handler(irq, handle_edge_irq);
291 break;
292 }
293 set_irq_flags(irq, IRQF_VALID);
294 }
295
ixp23xx_init_irq(void)296 void __init ixp23xx_init_irq(void)
297 {
298 int irq;
299
300 /* Route everything to IRQ */
301 *IXP23XX_INTR_SEL1 = 0x0;
302 *IXP23XX_INTR_SEL2 = 0x0;
303 *IXP23XX_INTR_SEL3 = 0x0;
304 *IXP23XX_INTR_SEL4 = 0x0;
305
306 /* Mask all sources */
307 *IXP23XX_INTR_EN1 = 0x0;
308 *IXP23XX_INTR_EN2 = 0x0;
309 *IXP23XX_INTR_EN3 = 0x0;
310 *IXP23XX_INTR_EN4 = 0x0;
311
312 /*
313 * Configure all IRQs for level-sensitive operation
314 */
315 for (irq = 0; irq <= NUM_IXP23XX_RAW_IRQS; irq++) {
316 ixp23xx_config_irq(irq, IXP23XX_IRQ_LEVEL);
317 }
318
319 for (irq = IRQ_IXP23XX_INTA; irq <= IRQ_IXP23XX_INTB; irq++) {
320 set_irq_chip(irq, &ixp23xx_pci_irq_chip);
321 set_irq_handler(irq, handle_level_irq);
322 set_irq_flags(irq, IRQF_VALID);
323 }
324
325 set_irq_chained_handler(IRQ_IXP23XX_PCI_INT_RPH, pci_handler);
326 }
327
328
329 /*************************************************************************
330 * Timer-tick functions for IXP23xx
331 *************************************************************************/
332 #define CLOCK_TICKS_PER_USEC (CLOCK_TICK_RATE / USEC_PER_SEC)
333
334 static unsigned long next_jiffy_time;
335
336 static unsigned long
ixp23xx_gettimeoffset(void)337 ixp23xx_gettimeoffset(void)
338 {
339 unsigned long elapsed;
340
341 elapsed = *IXP23XX_TIMER_CONT - (next_jiffy_time - LATCH);
342
343 return elapsed / CLOCK_TICKS_PER_USEC;
344 }
345
346 static irqreturn_t
ixp23xx_timer_interrupt(int irq,void * dev_id)347 ixp23xx_timer_interrupt(int irq, void *dev_id)
348 {
349 /* Clear Pending Interrupt by writing '1' to it */
350 *IXP23XX_TIMER_STATUS = IXP23XX_TIMER1_INT_PEND;
351 while ((signed long)(*IXP23XX_TIMER_CONT - next_jiffy_time) >= LATCH) {
352 timer_tick();
353 next_jiffy_time += LATCH;
354 }
355
356 return IRQ_HANDLED;
357 }
358
359 static struct irqaction ixp23xx_timer_irq = {
360 .name = "IXP23xx Timer Tick",
361 .handler = ixp23xx_timer_interrupt,
362 .flags = IRQF_DISABLED | IRQF_TIMER | IRQF_IRQPOLL,
363 };
364
ixp23xx_init_timer(void)365 void __init ixp23xx_init_timer(void)
366 {
367 /* Clear Pending Interrupt by writing '1' to it */
368 *IXP23XX_TIMER_STATUS = IXP23XX_TIMER1_INT_PEND;
369
370 /* Setup the Timer counter value */
371 *IXP23XX_TIMER1_RELOAD =
372 (LATCH & ~IXP23XX_TIMER_RELOAD_MASK) | IXP23XX_TIMER_ENABLE;
373
374 *IXP23XX_TIMER_CONT = 0;
375 next_jiffy_time = LATCH;
376
377 /* Connect the interrupt handler and enable the interrupt */
378 setup_irq(IRQ_IXP23XX_TIMER1, &ixp23xx_timer_irq);
379 }
380
381 struct sys_timer ixp23xx_timer = {
382 .init = ixp23xx_init_timer,
383 .offset = ixp23xx_gettimeoffset,
384 };
385
386
387 /*************************************************************************
388 * IXP23xx Platform Initialization
389 *************************************************************************/
390 static struct resource ixp23xx_uart_resources[] = {
391 {
392 .start = IXP23XX_UART1_PHYS,
393 .end = IXP23XX_UART1_PHYS + 0x0fff,
394 .flags = IORESOURCE_MEM
395 }, {
396 .start = IXP23XX_UART2_PHYS,
397 .end = IXP23XX_UART2_PHYS + 0x0fff,
398 .flags = IORESOURCE_MEM
399 }
400 };
401
402 static struct plat_serial8250_port ixp23xx_uart_data[] = {
403 {
404 .mapbase = IXP23XX_UART1_PHYS,
405 .membase = (char *)(IXP23XX_UART1_VIRT + 3),
406 .irq = IRQ_IXP23XX_UART1,
407 .flags = UPF_BOOT_AUTOCONF | UPF_SKIP_TEST,
408 .iotype = UPIO_MEM,
409 .regshift = 2,
410 .uartclk = IXP23XX_UART_XTAL,
411 }, {
412 .mapbase = IXP23XX_UART2_PHYS,
413 .membase = (char *)(IXP23XX_UART2_VIRT + 3),
414 .irq = IRQ_IXP23XX_UART2,
415 .flags = UPF_BOOT_AUTOCONF | UPF_SKIP_TEST,
416 .iotype = UPIO_MEM,
417 .regshift = 2,
418 .uartclk = IXP23XX_UART_XTAL,
419 },
420 { },
421 };
422
423 static struct platform_device ixp23xx_uart = {
424 .name = "serial8250",
425 .id = 0,
426 .dev.platform_data = ixp23xx_uart_data,
427 .num_resources = 2,
428 .resource = ixp23xx_uart_resources,
429 };
430
431 static struct platform_device *ixp23xx_devices[] __initdata = {
432 &ixp23xx_uart,
433 };
434
ixp23xx_sys_init(void)435 void __init ixp23xx_sys_init(void)
436 {
437 *IXP23XX_EXP_UNIT_FUSE |= 0xf;
438 platform_add_devices(ixp23xx_devices, ARRAY_SIZE(ixp23xx_devices));
439 }
440