avoid endless loops in lib/swiotlb.c
[wrt350n-kernel.git] / arch / arm / mach-footbridge / dc21285.c
blobd0dc51e813384f7ba02312efd249b49637ecfbb6
1 /*
2 * linux/arch/arm/kernel/dec21285.c: PCI functions for DC21285
4 * Copyright (C) 1998-2001 Russell King
5 * Copyright (C) 1998-2000 Phil Blundell
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
11 #include <linux/kernel.h>
12 #include <linux/pci.h>
13 #include <linux/interrupt.h>
14 #include <linux/mm.h>
15 #include <linux/slab.h>
16 #include <linux/init.h>
17 #include <linux/ioport.h>
18 #include <linux/irq.h>
20 #include <asm/io.h>
21 #include <asm/irq.h>
22 #include <asm/system.h>
23 #include <asm/mach/pci.h>
24 #include <asm/hardware/dec21285.h>
26 #define MAX_SLOTS 21
28 #define PCICMD_ABORT ((PCI_STATUS_REC_MASTER_ABORT| \
29 PCI_STATUS_REC_TARGET_ABORT)<<16)
31 #define PCICMD_ERROR_BITS ((PCI_STATUS_DETECTED_PARITY | \
32 PCI_STATUS_REC_MASTER_ABORT | \
33 PCI_STATUS_REC_TARGET_ABORT | \
34 PCI_STATUS_PARITY) << 16)
36 extern int setup_arm_irq(int, struct irqaction *);
37 extern void pcibios_report_status(u_int status_mask, int warn);
39 static unsigned long
40 dc21285_base_address(struct pci_bus *bus, unsigned int devfn)
42 unsigned long addr = 0;
44 if (bus->number == 0) {
45 if (PCI_SLOT(devfn) == 0)
47 * For devfn 0, point at the 21285
49 addr = ARMCSR_BASE;
50 else {
51 devfn -= 1 << 3;
53 if (devfn < PCI_DEVFN(MAX_SLOTS, 0))
54 addr = PCICFG0_BASE | 0xc00000 | (devfn << 8);
56 } else
57 addr = PCICFG1_BASE | (bus->number << 16) | (devfn << 8);
59 return addr;
62 static int
63 dc21285_read_config(struct pci_bus *bus, unsigned int devfn, int where,
64 int size, u32 *value)
66 unsigned long addr = dc21285_base_address(bus, devfn);
67 u32 v = 0xffffffff;
69 if (addr)
70 switch (size) {
71 case 1:
72 asm("ldrb %0, [%1, %2]"
73 : "=r" (v) : "r" (addr), "r" (where) : "cc");
74 break;
75 case 2:
76 asm("ldrh %0, [%1, %2]"
77 : "=r" (v) : "r" (addr), "r" (where) : "cc");
78 break;
79 case 4:
80 asm("ldr %0, [%1, %2]"
81 : "=r" (v) : "r" (addr), "r" (where) : "cc");
82 break;
85 *value = v;
87 v = *CSR_PCICMD;
88 if (v & PCICMD_ABORT) {
89 *CSR_PCICMD = v & (0xffff|PCICMD_ABORT);
90 return -1;
93 return PCIBIOS_SUCCESSFUL;
96 static int
97 dc21285_write_config(struct pci_bus *bus, unsigned int devfn, int where,
98 int size, u32 value)
100 unsigned long addr = dc21285_base_address(bus, devfn);
101 u32 v;
103 if (addr)
104 switch (size) {
105 case 1:
106 asm("strb %0, [%1, %2]"
107 : : "r" (value), "r" (addr), "r" (where)
108 : "cc");
109 break;
110 case 2:
111 asm("strh %0, [%1, %2]"
112 : : "r" (value), "r" (addr), "r" (where)
113 : "cc");
114 break;
115 case 4:
116 asm("str %0, [%1, %2]"
117 : : "r" (value), "r" (addr), "r" (where)
118 : "cc");
119 break;
122 v = *CSR_PCICMD;
123 if (v & PCICMD_ABORT) {
124 *CSR_PCICMD = v & (0xffff|PCICMD_ABORT);
125 return -1;
128 return PCIBIOS_SUCCESSFUL;
131 static struct pci_ops dc21285_ops = {
132 .read = dc21285_read_config,
133 .write = dc21285_write_config,
136 static struct timer_list serr_timer;
137 static struct timer_list perr_timer;
139 static void dc21285_enable_error(unsigned long __data)
141 switch (__data) {
142 case IRQ_PCI_SERR:
143 del_timer(&serr_timer);
144 break;
146 case IRQ_PCI_PERR:
147 del_timer(&perr_timer);
148 break;
151 enable_irq(__data);
155 * Warn on PCI errors.
157 static irqreturn_t dc21285_abort_irq(int irq, void *dev_id)
159 unsigned int cmd;
160 unsigned int status;
162 cmd = *CSR_PCICMD;
163 status = cmd >> 16;
164 cmd = cmd & 0xffff;
166 if (status & PCI_STATUS_REC_MASTER_ABORT) {
167 printk(KERN_DEBUG "PCI: master abort, pc=0x%08lx\n",
168 instruction_pointer(get_irq_regs()));
169 cmd |= PCI_STATUS_REC_MASTER_ABORT << 16;
172 if (status & PCI_STATUS_REC_TARGET_ABORT) {
173 printk(KERN_DEBUG "PCI: target abort: ");
174 pcibios_report_status(PCI_STATUS_REC_MASTER_ABORT |
175 PCI_STATUS_SIG_TARGET_ABORT |
176 PCI_STATUS_REC_TARGET_ABORT, 1);
177 printk("\n");
179 cmd |= PCI_STATUS_REC_TARGET_ABORT << 16;
182 *CSR_PCICMD = cmd;
184 return IRQ_HANDLED;
187 static irqreturn_t dc21285_serr_irq(int irq, void *dev_id)
189 struct timer_list *timer = dev_id;
190 unsigned int cntl;
192 printk(KERN_DEBUG "PCI: system error received: ");
193 pcibios_report_status(PCI_STATUS_SIG_SYSTEM_ERROR, 1);
194 printk("\n");
196 cntl = *CSR_SA110_CNTL & 0xffffdf07;
197 *CSR_SA110_CNTL = cntl | SA110_CNTL_RXSERR;
200 * back off this interrupt
202 disable_irq(irq);
203 timer->expires = jiffies + HZ;
204 add_timer(timer);
206 return IRQ_HANDLED;
209 static irqreturn_t dc21285_discard_irq(int irq, void *dev_id)
211 printk(KERN_DEBUG "PCI: discard timer expired\n");
212 *CSR_SA110_CNTL &= 0xffffde07;
214 return IRQ_HANDLED;
217 static irqreturn_t dc21285_dparity_irq(int irq, void *dev_id)
219 unsigned int cmd;
221 printk(KERN_DEBUG "PCI: data parity error detected: ");
222 pcibios_report_status(PCI_STATUS_PARITY | PCI_STATUS_DETECTED_PARITY, 1);
223 printk("\n");
225 cmd = *CSR_PCICMD & 0xffff;
226 *CSR_PCICMD = cmd | 1 << 24;
228 return IRQ_HANDLED;
231 static irqreturn_t dc21285_parity_irq(int irq, void *dev_id)
233 struct timer_list *timer = dev_id;
234 unsigned int cmd;
236 printk(KERN_DEBUG "PCI: parity error detected: ");
237 pcibios_report_status(PCI_STATUS_PARITY | PCI_STATUS_DETECTED_PARITY, 1);
238 printk("\n");
240 cmd = *CSR_PCICMD & 0xffff;
241 *CSR_PCICMD = cmd | 1 << 31;
244 * back off this interrupt
246 disable_irq(irq);
247 timer->expires = jiffies + HZ;
248 add_timer(timer);
250 return IRQ_HANDLED;
253 int __init dc21285_setup(int nr, struct pci_sys_data *sys)
255 struct resource *res;
257 if (nr || !footbridge_cfn_mode())
258 return 0;
260 res = kzalloc(sizeof(struct resource) * 2, GFP_KERNEL);
261 if (!res) {
262 printk("out of memory for root bus resources");
263 return 0;
266 res[0].flags = IORESOURCE_MEM;
267 res[0].name = "Footbridge non-prefetch";
268 res[1].flags = IORESOURCE_MEM | IORESOURCE_PREFETCH;
269 res[1].name = "Footbridge prefetch";
271 allocate_resource(&iomem_resource, &res[1], 0x20000000,
272 0xa0000000, 0xffffffff, 0x20000000, NULL, NULL);
273 allocate_resource(&iomem_resource, &res[0], 0x40000000,
274 0x80000000, 0xffffffff, 0x40000000, NULL, NULL);
276 sys->resource[0] = &ioport_resource;
277 sys->resource[1] = &res[0];
278 sys->resource[2] = &res[1];
279 sys->mem_offset = DC21285_PCI_MEM;
281 return 1;
284 struct pci_bus * __init dc21285_scan_bus(int nr, struct pci_sys_data *sys)
286 return pci_scan_bus(0, &dc21285_ops, sys);
289 void __init dc21285_preinit(void)
291 unsigned int mem_size, mem_mask;
292 int cfn_mode;
294 mem_size = (unsigned int)high_memory - PAGE_OFFSET;
295 for (mem_mask = 0x00100000; mem_mask < 0x10000000; mem_mask <<= 1)
296 if (mem_mask >= mem_size)
297 break;
300 * These registers need to be set up whether we're the
301 * central function or not.
303 *CSR_SDRAMBASEMASK = (mem_mask - 1) & 0x0ffc0000;
304 *CSR_SDRAMBASEOFFSET = 0;
305 *CSR_ROMBASEMASK = 0x80000000;
306 *CSR_CSRBASEMASK = 0;
307 *CSR_CSRBASEOFFSET = 0;
308 *CSR_PCIADDR_EXTN = 0;
310 cfn_mode = __footbridge_cfn_mode();
312 printk(KERN_INFO "PCI: DC21285 footbridge, revision %02lX, in "
313 "%s mode\n", *CSR_CLASSREV & 0xff, cfn_mode ?
314 "central function" : "addin");
316 if (footbridge_cfn_mode()) {
318 * Clear any existing errors - we aren't
319 * interested in historical data...
321 *CSR_SA110_CNTL = (*CSR_SA110_CNTL & 0xffffde07) |
322 SA110_CNTL_RXSERR;
323 *CSR_PCICMD = (*CSR_PCICMD & 0xffff) | PCICMD_ERROR_BITS;
326 init_timer(&serr_timer);
327 init_timer(&perr_timer);
329 serr_timer.data = IRQ_PCI_SERR;
330 serr_timer.function = dc21285_enable_error;
331 perr_timer.data = IRQ_PCI_PERR;
332 perr_timer.function = dc21285_enable_error;
335 * We don't care if these fail.
337 request_irq(IRQ_PCI_SERR, dc21285_serr_irq, IRQF_DISABLED,
338 "PCI system error", &serr_timer);
339 request_irq(IRQ_PCI_PERR, dc21285_parity_irq, IRQF_DISABLED,
340 "PCI parity error", &perr_timer);
341 request_irq(IRQ_PCI_ABORT, dc21285_abort_irq, IRQF_DISABLED,
342 "PCI abort", NULL);
343 request_irq(IRQ_DISCARD_TIMER, dc21285_discard_irq, IRQF_DISABLED,
344 "Discard timer", NULL);
345 request_irq(IRQ_PCI_DPERR, dc21285_dparity_irq, IRQF_DISABLED,
346 "PCI data parity", NULL);
348 if (cfn_mode) {
349 static struct resource csrio;
351 csrio.flags = IORESOURCE_IO;
352 csrio.name = "Footbridge";
354 allocate_resource(&ioport_resource, &csrio, 128,
355 0xff00, 0xffff, 128, NULL, NULL);
358 * Map our SDRAM at a known address in PCI space, just in case
359 * the firmware had other ideas. Using a nonzero base is
360 * necessary, since some VGA cards forcefully use PCI addresses
361 * in the range 0x000a0000 to 0x000c0000. (eg, S3 cards).
363 *CSR_PCICSRBASE = 0xf4000000;
364 *CSR_PCICSRIOBASE = csrio.start;
365 *CSR_PCISDRAMBASE = __virt_to_bus(PAGE_OFFSET);
366 *CSR_PCIROMBASE = 0;
367 *CSR_PCICMD = PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER |
368 PCI_COMMAND_INVALIDATE | PCICMD_ERROR_BITS;
369 } else if (footbridge_cfn_mode() != 0) {
371 * If we are not compiled to accept "add-in" mode, then
372 * we are using a constant virt_to_bus translation which
373 * can not hope to cater for the way the host BIOS has
374 * set up the machine.
376 panic("PCI: this kernel is compiled for central "
377 "function mode only");
381 void __init dc21285_postinit(void)
383 register_isa_ports(DC21285_PCI_MEM, DC21285_PCI_IO, 0);