1 /*
2 * arch/arm/mach-ixp4xx/common-pci.c
3 *
4 * IXP4XX PCI routines for all platforms
5 *
6 * Maintainer: Deepak Saxena <dsaxena@plexity.net>
7 *
8 * Copyright (C) 2002 Intel Corporation.
9 * Copyright (C) 2003 Greg Ungerer <gerg@snapgear.com>
10 * Copyright (C) 2003-2004 MontaVista Software, Inc.
11 *
12 * This program is free software; you can redistribute it and/or modify
13 * it under the terms of the GNU General Public License version 2 as
14 * published by the Free Software Foundation.
15 *
16 */
17
18 #include <linux/sched.h>
19 #include <linux/kernel.h>
20 #include <linux/pci.h>
21 #include <linux/interrupt.h>
22 #include <linux/mm.h>
23 #include <linux/init.h>
24 #include <linux/ioport.h>
25 #include <linux/slab.h>
26 #include <linux/delay.h>
27 #include <linux/device.h>
28 #include <linux/io.h>
29 #include <linux/export.h>
30 #include <asm/dma-mapping.h>
31
32 #include <asm/cputype.h>
33 #include <asm/irq.h>
34 #include <asm/sizes.h>
35 #include <asm/mach/pci.h>
36 #include <mach/hardware.h>
37
38
39 /*
40 * IXP4xx PCI read function is dependent on whether we are
41 * running A0 or B0 (AppleGate) silicon.
42 */
43 int (*ixp4xx_pci_read)(u32 addr, u32 cmd, u32* data);
44
45 /*
46 * Base address for PCI regsiter region
47 */
48 unsigned long ixp4xx_pci_reg_base = 0;
49
50 /*
51 * PCI cfg an I/O routines are done by programming a
52 * command/byte enable register, and then read/writing
53 * the data from a data regsiter. We need to ensure
54 * these transactions are atomic or we will end up
55 * with corrupt data on the bus or in a driver.
56 */
57 static DEFINE_RAW_SPINLOCK(ixp4xx_pci_lock);
58
59 /*
60 * Read from PCI config space
61 */
crp_read(u32 ad_cbe,u32 * data)62 static void crp_read(u32 ad_cbe, u32 *data)
63 {
64 unsigned long flags;
65 raw_spin_lock_irqsave(&ixp4xx_pci_lock, flags);
66 *PCI_CRP_AD_CBE = ad_cbe;
67 *data = *PCI_CRP_RDATA;
68 raw_spin_unlock_irqrestore(&ixp4xx_pci_lock, flags);
69 }
70
71 /*
72 * Write to PCI config space
73 */
crp_write(u32 ad_cbe,u32 data)74 static void crp_write(u32 ad_cbe, u32 data)
75 {
76 unsigned long flags;
77 raw_spin_lock_irqsave(&ixp4xx_pci_lock, flags);
78 *PCI_CRP_AD_CBE = CRP_AD_CBE_WRITE | ad_cbe;
79 *PCI_CRP_WDATA = data;
80 raw_spin_unlock_irqrestore(&ixp4xx_pci_lock, flags);
81 }
82
check_master_abort(void)83 static inline int check_master_abort(void)
84 {
85 /* check Master Abort bit after access */
86 unsigned long isr = *PCI_ISR;
87
88 if (isr & PCI_ISR_PFE) {
89 /* make sure the Master Abort bit is reset */
90 *PCI_ISR = PCI_ISR_PFE;
91 pr_debug("%s failed\n", __func__);
92 return 1;
93 }
94
95 return 0;
96 }
97
ixp4xx_pci_read_errata(u32 addr,u32 cmd,u32 * data)98 int ixp4xx_pci_read_errata(u32 addr, u32 cmd, u32* data)
99 {
100 unsigned long flags;
101 int retval = 0;
102 int i;
103
104 raw_spin_lock_irqsave(&ixp4xx_pci_lock, flags);
105
106 *PCI_NP_AD = addr;
107
108 /*
109 * PCI workaround - only works if NP PCI space reads have
110 * no side effects!!! Read 8 times. last one will be good.
111 */
112 for (i = 0; i < 8; i++) {
113 *PCI_NP_CBE = cmd;
114 *data = *PCI_NP_RDATA;
115 *data = *PCI_NP_RDATA;
116 }
117
118 if(check_master_abort())
119 retval = 1;
120
121 raw_spin_unlock_irqrestore(&ixp4xx_pci_lock, flags);
122 return retval;
123 }
124
ixp4xx_pci_read_no_errata(u32 addr,u32 cmd,u32 * data)125 int ixp4xx_pci_read_no_errata(u32 addr, u32 cmd, u32* data)
126 {
127 unsigned long flags;
128 int retval = 0;
129
130 raw_spin_lock_irqsave(&ixp4xx_pci_lock, flags);
131
132 *PCI_NP_AD = addr;
133
134 /* set up and execute the read */
135 *PCI_NP_CBE = cmd;
136
137 /* the result of the read is now in NP_RDATA */
138 *data = *PCI_NP_RDATA;
139
140 if(check_master_abort())
141 retval = 1;
142
143 raw_spin_unlock_irqrestore(&ixp4xx_pci_lock, flags);
144 return retval;
145 }
146
ixp4xx_pci_write(u32 addr,u32 cmd,u32 data)147 int ixp4xx_pci_write(u32 addr, u32 cmd, u32 data)
148 {
149 unsigned long flags;
150 int retval = 0;
151
152 raw_spin_lock_irqsave(&ixp4xx_pci_lock, flags);
153
154 *PCI_NP_AD = addr;
155
156 /* set up the write */
157 *PCI_NP_CBE = cmd;
158
159 /* execute the write by writing to NP_WDATA */
160 *PCI_NP_WDATA = data;
161
162 if(check_master_abort())
163 retval = 1;
164
165 raw_spin_unlock_irqrestore(&ixp4xx_pci_lock, flags);
166 return retval;
167 }
168
ixp4xx_config_addr(u8 bus_num,u16 devfn,int where)169 static u32 ixp4xx_config_addr(u8 bus_num, u16 devfn, int where)
170 {
171 u32 addr;
172 if (!bus_num) {
173 /* type 0 */
174 addr = BIT(32-PCI_SLOT(devfn)) | ((PCI_FUNC(devfn)) << 8) |
175 (where & ~3);
176 } else {
177 /* type 1 */
178 addr = (bus_num << 16) | ((PCI_SLOT(devfn)) << 11) |
179 ((PCI_FUNC(devfn)) << 8) | (where & ~3) | 1;
180 }
181 return addr;
182 }
183
184 /*
185 * Mask table, bits to mask for quantity of size 1, 2 or 4 bytes.
186 * 0 and 3 are not valid indexes...
187 */
188 static u32 bytemask[] = {
189 /*0*/ 0,
190 /*1*/ 0xff,
191 /*2*/ 0xffff,
192 /*3*/ 0,
193 /*4*/ 0xffffffff,
194 };
195
local_byte_lane_enable_bits(u32 n,int size)196 static u32 local_byte_lane_enable_bits(u32 n, int size)
197 {
198 if (size == 1)
199 return (0xf & ~BIT(n)) << CRP_AD_CBE_BESL;
200 if (size == 2)
201 return (0xf & ~(BIT(n) | BIT(n+1))) << CRP_AD_CBE_BESL;
202 if (size == 4)
203 return 0;
204 return 0xffffffff;
205 }
206
local_read_config(int where,int size,u32 * value)207 static int local_read_config(int where, int size, u32 *value)
208 {
209 u32 n, data;
210 pr_debug("local_read_config from %d size %d\n", where, size);
211 n = where % 4;
212 crp_read(where & ~3, &data);
213 *value = (data >> (8*n)) & bytemask[size];
214 pr_debug("local_read_config read %#x\n", *value);
215 return PCIBIOS_SUCCESSFUL;
216 }
217
local_write_config(int where,int size,u32 value)218 static int local_write_config(int where, int size, u32 value)
219 {
220 u32 n, byte_enables, data;
221 pr_debug("local_write_config %#x to %d size %d\n", value, where, size);
222 n = where % 4;
223 byte_enables = local_byte_lane_enable_bits(n, size);
224 if (byte_enables == 0xffffffff)
225 return PCIBIOS_BAD_REGISTER_NUMBER;
226 data = value << (8*n);
227 crp_write((where & ~3) | byte_enables, data);
228 return PCIBIOS_SUCCESSFUL;
229 }
230
byte_lane_enable_bits(u32 n,int size)231 static u32 byte_lane_enable_bits(u32 n, int size)
232 {
233 if (size == 1)
234 return (0xf & ~BIT(n)) << 4;
235 if (size == 2)
236 return (0xf & ~(BIT(n) | BIT(n+1))) << 4;
237 if (size == 4)
238 return 0;
239 return 0xffffffff;
240 }
241
ixp4xx_pci_read_config(struct pci_bus * bus,unsigned int devfn,int where,int size,u32 * value)242 static int ixp4xx_pci_read_config(struct pci_bus *bus, unsigned int devfn, int where, int size, u32 *value)
243 {
244 u32 n, byte_enables, addr, data;
245 u8 bus_num = bus->number;
246
247 pr_debug("read_config from %d size %d dev %d:%d:%d\n", where, size,
248 bus_num, PCI_SLOT(devfn), PCI_FUNC(devfn));
249
250 *value = 0xffffffff;
251 n = where % 4;
252 byte_enables = byte_lane_enable_bits(n, size);
253 if (byte_enables == 0xffffffff)
254 return PCIBIOS_BAD_REGISTER_NUMBER;
255
256 addr = ixp4xx_config_addr(bus_num, devfn, where);
257 if (ixp4xx_pci_read(addr, byte_enables | NP_CMD_CONFIGREAD, &data))
258 return PCIBIOS_DEVICE_NOT_FOUND;
259
260 *value = (data >> (8*n)) & bytemask[size];
261 pr_debug("read_config_byte read %#x\n", *value);
262 return PCIBIOS_SUCCESSFUL;
263 }
264
ixp4xx_pci_write_config(struct pci_bus * bus,unsigned int devfn,int where,int size,u32 value)265 static int ixp4xx_pci_write_config(struct pci_bus *bus, unsigned int devfn, int where, int size, u32 value)
266 {
267 u32 n, byte_enables, addr, data;
268 u8 bus_num = bus->number;
269
270 pr_debug("write_config_byte %#x to %d size %d dev %d:%d:%d\n", value, where,
271 size, bus_num, PCI_SLOT(devfn), PCI_FUNC(devfn));
272
273 n = where % 4;
274 byte_enables = byte_lane_enable_bits(n, size);
275 if (byte_enables == 0xffffffff)
276 return PCIBIOS_BAD_REGISTER_NUMBER;
277
278 addr = ixp4xx_config_addr(bus_num, devfn, where);
279 data = value << (8*n);
280 if (ixp4xx_pci_write(addr, byte_enables | NP_CMD_CONFIGWRITE, data))
281 return PCIBIOS_DEVICE_NOT_FOUND;
282
283 return PCIBIOS_SUCCESSFUL;
284 }
285
286 struct pci_ops ixp4xx_ops = {
287 .read = ixp4xx_pci_read_config,
288 .write = ixp4xx_pci_write_config,
289 };
290
291 /*
292 * PCI abort handler
293 */
abort_handler(unsigned long addr,unsigned int fsr,struct pt_regs * regs)294 static int abort_handler(unsigned long addr, unsigned int fsr, struct pt_regs *regs)
295 {
296 u32 isr, status;
297
298 isr = *PCI_ISR;
299 local_read_config(PCI_STATUS, 2, &status);
300 pr_debug("PCI: abort_handler addr = %#lx, isr = %#x, "
301 "status = %#x\n", addr, isr, status);
302
303 /* make sure the Master Abort bit is reset */
304 *PCI_ISR = PCI_ISR_PFE;
305 status |= PCI_STATUS_REC_MASTER_ABORT;
306 local_write_config(PCI_STATUS, 2, status);
307
308 /*
309 * If it was an imprecise abort, then we need to correct the
310 * return address to be _after_ the instruction.
311 */
312 if (fsr & (1 << 10))
313 regs->ARM_pc += 4;
314
315 return 0;
316 }
317
318
ixp4xx_needs_bounce(struct device * dev,dma_addr_t dma_addr,size_t size)319 static int ixp4xx_needs_bounce(struct device *dev, dma_addr_t dma_addr, size_t size)
320 {
321 return (dma_addr + size) >= SZ_64M;
322 }
323
324 /*
325 * Setup DMA mask to 64MB on PCI devices. Ignore all other devices.
326 */
ixp4xx_pci_platform_notify(struct device * dev)327 static int ixp4xx_pci_platform_notify(struct device *dev)
328 {
329 if(dev->bus == &pci_bus_type) {
330 *dev->dma_mask = SZ_64M - 1;
331 dev->coherent_dma_mask = SZ_64M - 1;
332 dmabounce_register_dev(dev, 2048, 4096, ixp4xx_needs_bounce);
333 }
334 return 0;
335 }
336
ixp4xx_pci_platform_notify_remove(struct device * dev)337 static int ixp4xx_pci_platform_notify_remove(struct device *dev)
338 {
339 if(dev->bus == &pci_bus_type) {
340 dmabounce_unregister_dev(dev);
341 }
342 return 0;
343 }
344
ixp4xx_pci_preinit(void)345 void __init ixp4xx_pci_preinit(void)
346 {
347 unsigned long cpuid = read_cpuid_id();
348
349 #ifdef CONFIG_IXP4XX_INDIRECT_PCI
350 pcibios_min_mem = 0x10000000; /* 1 GB of indirect PCI MMIO space */
351 #else
352 pcibios_min_mem = 0x48000000; /* 64 MB of PCI MMIO space */
353 #endif
354 /*
355 * Determine which PCI read method to use.
356 * Rev 0 IXP425 requires workaround.
357 */
358 if (!(cpuid & 0xf) && cpu_is_ixp42x()) {
359 printk("PCI: IXP42x A0 silicon detected - "
360 "PCI Non-Prefetch Workaround Enabled\n");
361 ixp4xx_pci_read = ixp4xx_pci_read_errata;
362 } else
363 ixp4xx_pci_read = ixp4xx_pci_read_no_errata;
364
365
366 /* hook in our fault handler for PCI errors */
367 hook_fault_code(16+6, abort_handler, SIGBUS, 0,
368 "imprecise external abort");
369
370 pr_debug("setup PCI-AHB(inbound) and AHB-PCI(outbound) address mappings\n");
371
372 /*
373 * We use identity AHB->PCI address translation
374 * in the 0x48000000 to 0x4bffffff address space
375 */
376 *PCI_PCIMEMBASE = 0x48494A4B;
377
378 /*
379 * We also use identity PCI->AHB address translation
380 * in 4 16MB BARs that begin at the physical memory start
381 */
382 *PCI_AHBMEMBASE = (PHYS_OFFSET & 0xFF000000) +
383 ((PHYS_OFFSET & 0xFF000000) >> 8) +
384 ((PHYS_OFFSET & 0xFF000000) >> 16) +
385 ((PHYS_OFFSET & 0xFF000000) >> 24) +
386 0x00010203;
387
388 if (*PCI_CSR & PCI_CSR_HOST) {
389 printk("PCI: IXP4xx is host\n");
390
391 pr_debug("setup BARs in controller\n");
392
393 /*
394 * We configure the PCI inbound memory windows to be
395 * 1:1 mapped to SDRAM
396 */
397 local_write_config(PCI_BASE_ADDRESS_0, 4, PHYS_OFFSET);
398 local_write_config(PCI_BASE_ADDRESS_1, 4, PHYS_OFFSET + SZ_16M);
399 local_write_config(PCI_BASE_ADDRESS_2, 4, PHYS_OFFSET + SZ_32M);
400 local_write_config(PCI_BASE_ADDRESS_3, 4,
401 PHYS_OFFSET + SZ_32M + SZ_16M);
402
403 /*
404 * Enable CSR window at 64 MiB to allow PCI masters
405 * to continue prefetching past 64 MiB boundary.
406 */
407 local_write_config(PCI_BASE_ADDRESS_4, 4, PHYS_OFFSET + SZ_64M);
408
409 /*
410 * Enable the IO window to be way up high, at 0xfffffc00
411 */
412 local_write_config(PCI_BASE_ADDRESS_5, 4, 0xfffffc01);
413 } else {
414 printk("PCI: IXP4xx is target - No bus scan performed\n");
415 }
416
417 printk("PCI: IXP4xx Using %s access for memory space\n",
418 #ifndef CONFIG_IXP4XX_INDIRECT_PCI
419 "direct"
420 #else
421 "indirect"
422 #endif
423 );
424
425 pr_debug("clear error bits in ISR\n");
426 *PCI_ISR = PCI_ISR_PSE | PCI_ISR_PFE | PCI_ISR_PPE | PCI_ISR_AHBE;
427
428 /*
429 * Set Initialize Complete in PCI Control Register: allow IXP4XX to
430 * respond to PCI configuration cycles. Specify that the AHB bus is
431 * operating in big endian mode. Set up byte lane swapping between
432 * little-endian PCI and the big-endian AHB bus
433 */
434 #ifdef __ARMEB__
435 *PCI_CSR = PCI_CSR_IC | PCI_CSR_ABE | PCI_CSR_PDS | PCI_CSR_ADS;
436 #else
437 *PCI_CSR = PCI_CSR_IC | PCI_CSR_ABE;
438 #endif
439
440 pr_debug("DONE\n");
441 }
442
ixp4xx_setup(int nr,struct pci_sys_data * sys)443 int ixp4xx_setup(int nr, struct pci_sys_data *sys)
444 {
445 struct resource *res;
446
447 if (nr >= 1)
448 return 0;
449
450 res = kzalloc(sizeof(*res) * 2, GFP_KERNEL);
451 if (res == NULL) {
452 /*
453 * If we're out of memory this early, something is wrong,
454 * so we might as well catch it here.
455 */
456 panic("PCI: unable to allocate resources?\n");
457 }
458
459 local_write_config(PCI_COMMAND, 2, PCI_COMMAND_MASTER | PCI_COMMAND_MEMORY);
460
461 res[0].name = "PCI I/O Space";
462 res[0].start = 0x00000000;
463 res[0].end = 0x0000ffff;
464 res[0].flags = IORESOURCE_IO;
465
466 res[1].name = "PCI Memory Space";
467 res[1].start = PCIBIOS_MIN_MEM;
468 res[1].end = PCIBIOS_MAX_MEM;
469 res[1].flags = IORESOURCE_MEM;
470
471 request_resource(&ioport_resource, &res[0]);
472 request_resource(&iomem_resource, &res[1]);
473
474 pci_add_resource_offset(&sys->resources, &res[0], sys->io_offset);
475 pci_add_resource_offset(&sys->resources, &res[1], sys->mem_offset);
476
477 platform_notify = ixp4xx_pci_platform_notify;
478 platform_notify_remove = ixp4xx_pci_platform_notify_remove;
479
480 return 1;
481 }
482
ixp4xx_scan_bus(int nr,struct pci_sys_data * sys)483 struct pci_bus * __devinit ixp4xx_scan_bus(int nr, struct pci_sys_data *sys)
484 {
485 return pci_scan_root_bus(NULL, sys->busnr, &ixp4xx_ops, sys,
486 &sys->resources);
487 }
488
dma_set_coherent_mask(struct device * dev,u64 mask)489 int dma_set_coherent_mask(struct device *dev, u64 mask)
490 {
491 if (mask >= SZ_64M - 1)
492 return 0;
493
494 return -EIO;
495 }
496
497 EXPORT_SYMBOL(ixp4xx_pci_read);
498 EXPORT_SYMBOL(ixp4xx_pci_write);
499 EXPORT_SYMBOL(dma_set_coherent_mask);
500