avoid endless loops in lib/swiotlb.c
[wrt350n-kernel.git] / arch / arm / mach-ixp23xx / core.c
blob5fea5a132939abc1c608bec1a04940b7ae7612d6
1 /*
2 * arch/arm/mach-ixp23xx/core.c
4 * Core routines for IXP23xx chips
6 * Author: Deepak Saxena <dsaxena@plexity.net>
8 * Copyright 2005 (c) MontaVista Software, Inc.
10 * Based on 2.4 code Copyright 2004 (c) Intel Corporation
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.
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>
32 #include <asm/types.h>
33 #include <asm/setup.h>
34 #include <asm/memory.h>
35 #include <asm/hardware.h>
36 #include <asm/mach-types.h>
37 #include <asm/irq.h>
38 #include <asm/system.h>
39 #include <asm/tlbflush.h>
40 #include <asm/pgtable.h>
42 #include <asm/mach/map.h>
43 #include <asm/mach/time.h>
44 #include <asm/mach/irq.h>
45 #include <asm/mach/arch.h>
48 /*************************************************************************
49 * Chip specific mappings shared by all IXP23xx systems
50 *************************************************************************/
51 static struct map_desc ixp23xx_io_desc[] __initdata = {
52 { /* XSI-CPP CSRs */
53 .virtual = IXP23XX_XSI2CPP_CSR_VIRT,
54 .pfn = __phys_to_pfn(IXP23XX_XSI2CPP_CSR_PHYS),
55 .length = IXP23XX_XSI2CPP_CSR_SIZE,
56 .type = MT_DEVICE,
57 }, { /* Expansion Bus Config */
58 .virtual = IXP23XX_EXP_CFG_VIRT,
59 .pfn = __phys_to_pfn(IXP23XX_EXP_CFG_PHYS),
60 .length = IXP23XX_EXP_CFG_SIZE,
61 .type = MT_DEVICE,
62 }, { /* UART, Interrupt ctrl, GPIO, timers, NPEs, MACS,.... */
63 .virtual = IXP23XX_PERIPHERAL_VIRT,
64 .pfn = __phys_to_pfn(IXP23XX_PERIPHERAL_PHYS),
65 .length = IXP23XX_PERIPHERAL_SIZE,
66 .type = MT_DEVICE,
67 }, { /* CAP CSRs */
68 .virtual = IXP23XX_CAP_CSR_VIRT,
69 .pfn = __phys_to_pfn(IXP23XX_CAP_CSR_PHYS),
70 .length = IXP23XX_CAP_CSR_SIZE,
71 .type = MT_DEVICE,
72 }, { /* MSF CSRs */
73 .virtual = IXP23XX_MSF_CSR_VIRT,
74 .pfn = __phys_to_pfn(IXP23XX_MSF_CSR_PHYS),
75 .length = IXP23XX_MSF_CSR_SIZE,
76 .type = MT_DEVICE,
77 }, { /* PCI I/O Space */
78 .virtual = IXP23XX_PCI_IO_VIRT,
79 .pfn = __phys_to_pfn(IXP23XX_PCI_IO_PHYS),
80 .length = IXP23XX_PCI_IO_SIZE,
81 .type = MT_DEVICE,
82 }, { /* PCI Config Space */
83 .virtual = IXP23XX_PCI_CFG_VIRT,
84 .pfn = __phys_to_pfn(IXP23XX_PCI_CFG_PHYS),
85 .length = IXP23XX_PCI_CFG_SIZE,
86 .type = MT_DEVICE,
87 }, { /* PCI local CFG CSRs */
88 .virtual = IXP23XX_PCI_CREG_VIRT,
89 .pfn = __phys_to_pfn(IXP23XX_PCI_CREG_PHYS),
90 .length = IXP23XX_PCI_CREG_SIZE,
91 .type = MT_DEVICE,
92 }, { /* PCI MEM Space */
93 .virtual = IXP23XX_PCI_MEM_VIRT,
94 .pfn = __phys_to_pfn(IXP23XX_PCI_MEM_PHYS),
95 .length = IXP23XX_PCI_MEM_SIZE,
96 .type = MT_DEVICE,
100 void __init ixp23xx_map_io(void)
102 iotable_init(ixp23xx_io_desc, ARRAY_SIZE(ixp23xx_io_desc));
106 /***************************************************************************
107 * IXP23xx Interrupt Handling
108 ***************************************************************************/
109 enum ixp23xx_irq_type {
110 IXP23XX_IRQ_LEVEL, IXP23XX_IRQ_EDGE
113 static void ixp23xx_config_irq(unsigned int, enum ixp23xx_irq_type);
115 static int ixp23xx_irq_set_type(unsigned int irq, unsigned int type)
117 int line = irq - IRQ_IXP23XX_GPIO6 + 6;
118 u32 int_style;
119 enum ixp23xx_irq_type irq_type;
120 volatile u32 *int_reg;
123 * Only GPIOs 6-15 are wired to interrupts on IXP23xx
125 if (line < 6 || line > 15)
126 return -EINVAL;
128 switch (type) {
129 case IRQT_BOTHEDGE:
130 int_style = IXP23XX_GPIO_STYLE_TRANSITIONAL;
131 irq_type = IXP23XX_IRQ_EDGE;
132 break;
133 case IRQT_RISING:
134 int_style = IXP23XX_GPIO_STYLE_RISING_EDGE;
135 irq_type = IXP23XX_IRQ_EDGE;
136 break;
137 case IRQT_FALLING:
138 int_style = IXP23XX_GPIO_STYLE_FALLING_EDGE;
139 irq_type = IXP23XX_IRQ_EDGE;
140 break;
141 case IRQT_HIGH:
142 int_style = IXP23XX_GPIO_STYLE_ACTIVE_HIGH;
143 irq_type = IXP23XX_IRQ_LEVEL;
144 break;
145 case IRQT_LOW:
146 int_style = IXP23XX_GPIO_STYLE_ACTIVE_LOW;
147 irq_type = IXP23XX_IRQ_LEVEL;
148 break;
149 default:
150 return -EINVAL;
153 ixp23xx_config_irq(irq, irq_type);
155 if (line >= 8) { /* pins 8-15 */
156 line -= 8;
157 int_reg = (volatile u32 *)IXP23XX_GPIO_GPIT2R;
158 } else { /* pins 0-7 */
159 int_reg = (volatile u32 *)IXP23XX_GPIO_GPIT1R;
163 * Clear pending interrupts
165 *IXP23XX_GPIO_GPISR = (1 << line);
167 /* Clear the style for the appropriate pin */
168 *int_reg &= ~(IXP23XX_GPIO_STYLE_MASK <<
169 (line * IXP23XX_GPIO_STYLE_SIZE));
171 /* Set the new style */
172 *int_reg |= (int_style << (line * IXP23XX_GPIO_STYLE_SIZE));
174 return 0;
177 static void ixp23xx_irq_mask(unsigned int irq)
179 volatile unsigned long *intr_reg;
181 if (irq >= 56)
182 irq += 8;
184 intr_reg = IXP23XX_INTR_EN1 + (irq / 32);
185 *intr_reg &= ~(1 << (irq % 32));
188 static void ixp23xx_irq_ack(unsigned int irq)
190 int line = irq - IRQ_IXP23XX_GPIO6 + 6;
192 if ((line < 6) || (line > 15))
193 return;
195 *IXP23XX_GPIO_GPISR = (1 << line);
199 * Level triggered interrupts on GPIO lines can only be cleared when the
200 * interrupt condition disappears.
202 static void ixp23xx_irq_level_unmask(unsigned int irq)
204 volatile unsigned long *intr_reg;
206 ixp23xx_irq_ack(irq);
208 if (irq >= 56)
209 irq += 8;
211 intr_reg = IXP23XX_INTR_EN1 + (irq / 32);
212 *intr_reg |= (1 << (irq % 32));
215 static void ixp23xx_irq_edge_unmask(unsigned int irq)
217 volatile unsigned long *intr_reg;
219 if (irq >= 56)
220 irq += 8;
222 intr_reg = IXP23XX_INTR_EN1 + (irq / 32);
223 *intr_reg |= (1 << (irq % 32));
226 static struct irq_chip ixp23xx_irq_level_chip = {
227 .ack = ixp23xx_irq_mask,
228 .mask = ixp23xx_irq_mask,
229 .unmask = ixp23xx_irq_level_unmask,
230 .set_type = ixp23xx_irq_set_type
233 static struct irq_chip ixp23xx_irq_edge_chip = {
234 .ack = ixp23xx_irq_ack,
235 .mask = ixp23xx_irq_mask,
236 .unmask = ixp23xx_irq_edge_unmask,
237 .set_type = ixp23xx_irq_set_type
240 static void ixp23xx_pci_irq_mask(unsigned int irq)
242 *IXP23XX_PCI_XSCALE_INT_ENABLE &= ~(1 << (IRQ_IXP23XX_INTA + 27 - irq));
245 static void ixp23xx_pci_irq_unmask(unsigned int irq)
247 *IXP23XX_PCI_XSCALE_INT_ENABLE |= (1 << (IRQ_IXP23XX_INTA + 27 - irq));
251 * TODO: Should this just be done at ASM level?
253 static void pci_handler(unsigned int irq, struct irq_desc *desc)
255 u32 pci_interrupt;
256 unsigned int irqno;
257 struct irq_desc *int_desc;
259 pci_interrupt = *IXP23XX_PCI_XSCALE_INT_STATUS;
261 desc->chip->ack(irq);
263 /* See which PCI_INTA, or PCI_INTB interrupted */
264 if (pci_interrupt & (1 << 26)) {
265 irqno = IRQ_IXP23XX_INTB;
266 } else if (pci_interrupt & (1 << 27)) {
267 irqno = IRQ_IXP23XX_INTA;
268 } else {
269 BUG();
272 int_desc = irq_desc + irqno;
273 desc_handle_irq(irqno, int_desc);
275 desc->chip->unmask(irq);
278 static struct irq_chip ixp23xx_pci_irq_chip = {
279 .ack = ixp23xx_pci_irq_mask,
280 .mask = ixp23xx_pci_irq_mask,
281 .unmask = ixp23xx_pci_irq_unmask
284 static void ixp23xx_config_irq(unsigned int irq, enum ixp23xx_irq_type type)
286 switch (type) {
287 case IXP23XX_IRQ_LEVEL:
288 set_irq_chip(irq, &ixp23xx_irq_level_chip);
289 set_irq_handler(irq, handle_level_irq);
290 break;
291 case IXP23XX_IRQ_EDGE:
292 set_irq_chip(irq, &ixp23xx_irq_edge_chip);
293 set_irq_handler(irq, handle_edge_irq);
294 break;
296 set_irq_flags(irq, IRQF_VALID);
299 void __init ixp23xx_init_irq(void)
301 int irq;
303 /* Route everything to IRQ */
304 *IXP23XX_INTR_SEL1 = 0x0;
305 *IXP23XX_INTR_SEL2 = 0x0;
306 *IXP23XX_INTR_SEL3 = 0x0;
307 *IXP23XX_INTR_SEL4 = 0x0;
309 /* Mask all sources */
310 *IXP23XX_INTR_EN1 = 0x0;
311 *IXP23XX_INTR_EN2 = 0x0;
312 *IXP23XX_INTR_EN3 = 0x0;
313 *IXP23XX_INTR_EN4 = 0x0;
316 * Configure all IRQs for level-sensitive operation
318 for (irq = 0; irq <= NUM_IXP23XX_RAW_IRQS; irq++) {
319 ixp23xx_config_irq(irq, IXP23XX_IRQ_LEVEL);
322 for (irq = IRQ_IXP23XX_INTA; irq <= IRQ_IXP23XX_INTB; irq++) {
323 set_irq_chip(irq, &ixp23xx_pci_irq_chip);
324 set_irq_handler(irq, handle_level_irq);
325 set_irq_flags(irq, IRQF_VALID);
328 set_irq_chained_handler(IRQ_IXP23XX_PCI_INT_RPH, pci_handler);
332 /*************************************************************************
333 * Timer-tick functions for IXP23xx
334 *************************************************************************/
335 #define CLOCK_TICKS_PER_USEC (CLOCK_TICK_RATE / USEC_PER_SEC)
337 static unsigned long next_jiffy_time;
339 static unsigned long
340 ixp23xx_gettimeoffset(void)
342 unsigned long elapsed;
344 elapsed = *IXP23XX_TIMER_CONT - (next_jiffy_time - LATCH);
346 return elapsed / CLOCK_TICKS_PER_USEC;
349 static irqreturn_t
350 ixp23xx_timer_interrupt(int irq, void *dev_id)
352 /* Clear Pending Interrupt by writing '1' to it */
353 *IXP23XX_TIMER_STATUS = IXP23XX_TIMER1_INT_PEND;
354 while ((signed long)(*IXP23XX_TIMER_CONT - next_jiffy_time) >= LATCH) {
355 timer_tick();
356 next_jiffy_time += LATCH;
359 return IRQ_HANDLED;
362 static struct irqaction ixp23xx_timer_irq = {
363 .name = "IXP23xx Timer Tick",
364 .handler = ixp23xx_timer_interrupt,
365 .flags = IRQF_DISABLED | IRQF_TIMER | IRQF_IRQPOLL,
368 void __init ixp23xx_init_timer(void)
370 /* Clear Pending Interrupt by writing '1' to it */
371 *IXP23XX_TIMER_STATUS = IXP23XX_TIMER1_INT_PEND;
373 /* Setup the Timer counter value */
374 *IXP23XX_TIMER1_RELOAD =
375 (LATCH & ~IXP23XX_TIMER_RELOAD_MASK) | IXP23XX_TIMER_ENABLE;
377 *IXP23XX_TIMER_CONT = 0;
378 next_jiffy_time = LATCH;
380 /* Connect the interrupt handler and enable the interrupt */
381 setup_irq(IRQ_IXP23XX_TIMER1, &ixp23xx_timer_irq);
384 struct sys_timer ixp23xx_timer = {
385 .init = ixp23xx_init_timer,
386 .offset = ixp23xx_gettimeoffset,
390 /*************************************************************************
391 * IXP23xx Platform Initialization
392 *************************************************************************/
393 static struct resource ixp23xx_uart_resources[] = {
395 .start = IXP23XX_UART1_PHYS,
396 .end = IXP23XX_UART1_PHYS + 0x0fff,
397 .flags = IORESOURCE_MEM
398 }, {
399 .start = IXP23XX_UART2_PHYS,
400 .end = IXP23XX_UART2_PHYS + 0x0fff,
401 .flags = IORESOURCE_MEM
405 static struct plat_serial8250_port ixp23xx_uart_data[] = {
407 .mapbase = IXP23XX_UART1_PHYS,
408 .membase = (char *)(IXP23XX_UART1_VIRT + 3),
409 .irq = IRQ_IXP23XX_UART1,
410 .flags = UPF_BOOT_AUTOCONF | UPF_SKIP_TEST,
411 .iotype = UPIO_MEM,
412 .regshift = 2,
413 .uartclk = IXP23XX_UART_XTAL,
414 }, {
415 .mapbase = IXP23XX_UART2_PHYS,
416 .membase = (char *)(IXP23XX_UART2_VIRT + 3),
417 .irq = IRQ_IXP23XX_UART2,
418 .flags = UPF_BOOT_AUTOCONF | UPF_SKIP_TEST,
419 .iotype = UPIO_MEM,
420 .regshift = 2,
421 .uartclk = IXP23XX_UART_XTAL,
423 { },
426 static struct platform_device ixp23xx_uart = {
427 .name = "serial8250",
428 .id = 0,
429 .dev.platform_data = ixp23xx_uart_data,
430 .num_resources = 2,
431 .resource = ixp23xx_uart_resources,
434 static struct platform_device *ixp23xx_devices[] __initdata = {
435 &ixp23xx_uart,
438 void __init ixp23xx_sys_init(void)
440 *IXP23XX_EXP_UNIT_FUSE |= 0xf;
441 platform_add_devices(ixp23xx_devices, ARRAY_SIZE(ixp23xx_devices));