staging: brcm80211: decreased indentation level of brcms_c_wme_setparams function
[zen-stable.git] / arch / powerpc / platforms / cell / axon_msi.c
blobac06903e136a2df7f9b871013878c7fcb7aed761
1 /*
2 * Copyright 2007, Michael Ellerman, IBM Corporation.
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License
6 * as published by the Free Software Foundation; either version
7 * 2 of the License, or (at your option) any later version.
8 */
11 #include <linux/interrupt.h>
12 #include <linux/irq.h>
13 #include <linux/kernel.h>
14 #include <linux/pci.h>
15 #include <linux/msi.h>
16 #include <linux/of_platform.h>
17 #include <linux/debugfs.h>
18 #include <linux/slab.h>
20 #include <asm/dcr.h>
21 #include <asm/machdep.h>
22 #include <asm/prom.h>
26 * MSIC registers, specified as offsets from dcr_base
28 #define MSIC_CTRL_REG 0x0
30 /* Base Address registers specify FIFO location in BE memory */
31 #define MSIC_BASE_ADDR_HI_REG 0x3
32 #define MSIC_BASE_ADDR_LO_REG 0x4
34 /* Hold the read/write offsets into the FIFO */
35 #define MSIC_READ_OFFSET_REG 0x5
36 #define MSIC_WRITE_OFFSET_REG 0x6
39 /* MSIC control register flags */
40 #define MSIC_CTRL_ENABLE 0x0001
41 #define MSIC_CTRL_FIFO_FULL_ENABLE 0x0002
42 #define MSIC_CTRL_IRQ_ENABLE 0x0008
43 #define MSIC_CTRL_FULL_STOP_ENABLE 0x0010
46 * The MSIC can be configured to use a FIFO of 32KB, 64KB, 128KB or 256KB.
47 * Currently we're using a 64KB FIFO size.
49 #define MSIC_FIFO_SIZE_SHIFT 16
50 #define MSIC_FIFO_SIZE_BYTES (1 << MSIC_FIFO_SIZE_SHIFT)
53 * To configure the FIFO size as (1 << n) bytes, we write (n - 15) into bits
54 * 8-9 of the MSIC control reg.
56 #define MSIC_CTRL_FIFO_SIZE (((MSIC_FIFO_SIZE_SHIFT - 15) << 8) & 0x300)
59 * We need to mask the read/write offsets to make sure they stay within
60 * the bounds of the FIFO. Also they should always be 16-byte aligned.
62 #define MSIC_FIFO_SIZE_MASK ((MSIC_FIFO_SIZE_BYTES - 1) & ~0xFu)
64 /* Each entry in the FIFO is 16 bytes, the first 4 bytes hold the irq # */
65 #define MSIC_FIFO_ENTRY_SIZE 0x10
68 struct axon_msic {
69 struct irq_host *irq_host;
70 __le32 *fifo_virt;
71 dma_addr_t fifo_phys;
72 dcr_host_t dcr_host;
73 u32 read_offset;
74 #ifdef DEBUG
75 u32 __iomem *trigger;
76 #endif
79 #ifdef DEBUG
80 void axon_msi_debug_setup(struct device_node *dn, struct axon_msic *msic);
81 #else
82 static inline void axon_msi_debug_setup(struct device_node *dn,
83 struct axon_msic *msic) { }
84 #endif
87 static void msic_dcr_write(struct axon_msic *msic, unsigned int dcr_n, u32 val)
89 pr_devel("axon_msi: dcr_write(0x%x, 0x%x)\n", val, dcr_n);
91 dcr_write(msic->dcr_host, dcr_n, val);
94 static void axon_msi_cascade(unsigned int irq, struct irq_desc *desc)
96 struct irq_chip *chip = irq_desc_get_chip(desc);
97 struct axon_msic *msic = irq_get_handler_data(irq);
98 u32 write_offset, msi;
99 int idx;
100 int retry = 0;
102 write_offset = dcr_read(msic->dcr_host, MSIC_WRITE_OFFSET_REG);
103 pr_devel("axon_msi: original write_offset 0x%x\n", write_offset);
105 /* write_offset doesn't wrap properly, so we have to mask it */
106 write_offset &= MSIC_FIFO_SIZE_MASK;
108 while (msic->read_offset != write_offset && retry < 100) {
109 idx = msic->read_offset / sizeof(__le32);
110 msi = le32_to_cpu(msic->fifo_virt[idx]);
111 msi &= 0xFFFF;
113 pr_devel("axon_msi: woff %x roff %x msi %x\n",
114 write_offset, msic->read_offset, msi);
116 if (msi < NR_IRQS && irq_get_chip_data(msi) == msic) {
117 generic_handle_irq(msi);
118 msic->fifo_virt[idx] = cpu_to_le32(0xffffffff);
119 } else {
121 * Reading the MSIC_WRITE_OFFSET_REG does not
122 * reliably flush the outstanding DMA to the
123 * FIFO buffer. Here we were reading stale
124 * data, so we need to retry.
126 udelay(1);
127 retry++;
128 pr_devel("axon_msi: invalid irq 0x%x!\n", msi);
129 continue;
132 if (retry) {
133 pr_devel("axon_msi: late irq 0x%x, retry %d\n",
134 msi, retry);
135 retry = 0;
138 msic->read_offset += MSIC_FIFO_ENTRY_SIZE;
139 msic->read_offset &= MSIC_FIFO_SIZE_MASK;
142 if (retry) {
143 printk(KERN_WARNING "axon_msi: irq timed out\n");
145 msic->read_offset += MSIC_FIFO_ENTRY_SIZE;
146 msic->read_offset &= MSIC_FIFO_SIZE_MASK;
149 chip->irq_eoi(&desc->irq_data);
152 static struct axon_msic *find_msi_translator(struct pci_dev *dev)
154 struct irq_host *irq_host;
155 struct device_node *dn, *tmp;
156 const phandle *ph;
157 struct axon_msic *msic = NULL;
159 dn = of_node_get(pci_device_to_OF_node(dev));
160 if (!dn) {
161 dev_dbg(&dev->dev, "axon_msi: no pci_dn found\n");
162 return NULL;
165 for (; dn; dn = of_get_next_parent(dn)) {
166 ph = of_get_property(dn, "msi-translator", NULL);
167 if (ph)
168 break;
171 if (!ph) {
172 dev_dbg(&dev->dev,
173 "axon_msi: no msi-translator property found\n");
174 goto out_error;
177 tmp = dn;
178 dn = of_find_node_by_phandle(*ph);
179 of_node_put(tmp);
180 if (!dn) {
181 dev_dbg(&dev->dev,
182 "axon_msi: msi-translator doesn't point to a node\n");
183 goto out_error;
186 irq_host = irq_find_host(dn);
187 if (!irq_host) {
188 dev_dbg(&dev->dev, "axon_msi: no irq_host found for node %s\n",
189 dn->full_name);
190 goto out_error;
193 msic = irq_host->host_data;
195 out_error:
196 of_node_put(dn);
198 return msic;
201 static int axon_msi_check_device(struct pci_dev *dev, int nvec, int type)
203 if (!find_msi_translator(dev))
204 return -ENODEV;
206 return 0;
209 static int setup_msi_msg_address(struct pci_dev *dev, struct msi_msg *msg)
211 struct device_node *dn;
212 struct msi_desc *entry;
213 int len;
214 const u32 *prop;
216 dn = of_node_get(pci_device_to_OF_node(dev));
217 if (!dn) {
218 dev_dbg(&dev->dev, "axon_msi: no pci_dn found\n");
219 return -ENODEV;
222 entry = list_first_entry(&dev->msi_list, struct msi_desc, list);
224 for (; dn; dn = of_get_next_parent(dn)) {
225 if (entry->msi_attrib.is_64) {
226 prop = of_get_property(dn, "msi-address-64", &len);
227 if (prop)
228 break;
231 prop = of_get_property(dn, "msi-address-32", &len);
232 if (prop)
233 break;
236 if (!prop) {
237 dev_dbg(&dev->dev,
238 "axon_msi: no msi-address-(32|64) properties found\n");
239 return -ENOENT;
242 switch (len) {
243 case 8:
244 msg->address_hi = prop[0];
245 msg->address_lo = prop[1];
246 break;
247 case 4:
248 msg->address_hi = 0;
249 msg->address_lo = prop[0];
250 break;
251 default:
252 dev_dbg(&dev->dev,
253 "axon_msi: malformed msi-address-(32|64) property\n");
254 of_node_put(dn);
255 return -EINVAL;
258 of_node_put(dn);
260 return 0;
263 static int axon_msi_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
265 unsigned int virq, rc;
266 struct msi_desc *entry;
267 struct msi_msg msg;
268 struct axon_msic *msic;
270 msic = find_msi_translator(dev);
271 if (!msic)
272 return -ENODEV;
274 rc = setup_msi_msg_address(dev, &msg);
275 if (rc)
276 return rc;
278 /* We rely on being able to stash a virq in a u16 */
279 BUILD_BUG_ON(NR_IRQS > 65536);
281 list_for_each_entry(entry, &dev->msi_list, list) {
282 virq = irq_create_direct_mapping(msic->irq_host);
283 if (virq == NO_IRQ) {
284 dev_warn(&dev->dev,
285 "axon_msi: virq allocation failed!\n");
286 return -1;
288 dev_dbg(&dev->dev, "axon_msi: allocated virq 0x%x\n", virq);
290 irq_set_msi_desc(virq, entry);
291 msg.data = virq;
292 write_msi_msg(virq, &msg);
295 return 0;
298 static void axon_msi_teardown_msi_irqs(struct pci_dev *dev)
300 struct msi_desc *entry;
302 dev_dbg(&dev->dev, "axon_msi: tearing down msi irqs\n");
304 list_for_each_entry(entry, &dev->msi_list, list) {
305 if (entry->irq == NO_IRQ)
306 continue;
308 irq_set_msi_desc(entry->irq, NULL);
309 irq_dispose_mapping(entry->irq);
313 static struct irq_chip msic_irq_chip = {
314 .irq_mask = mask_msi_irq,
315 .irq_unmask = unmask_msi_irq,
316 .irq_shutdown = mask_msi_irq,
317 .name = "AXON-MSI",
320 static int msic_host_map(struct irq_host *h, unsigned int virq,
321 irq_hw_number_t hw)
323 irq_set_chip_data(virq, h->host_data);
324 irq_set_chip_and_handler(virq, &msic_irq_chip, handle_simple_irq);
326 return 0;
329 static struct irq_host_ops msic_host_ops = {
330 .map = msic_host_map,
333 static void axon_msi_shutdown(struct platform_device *device)
335 struct axon_msic *msic = dev_get_drvdata(&device->dev);
336 u32 tmp;
338 pr_devel("axon_msi: disabling %s\n",
339 msic->irq_host->of_node->full_name);
340 tmp = dcr_read(msic->dcr_host, MSIC_CTRL_REG);
341 tmp &= ~MSIC_CTRL_ENABLE & ~MSIC_CTRL_IRQ_ENABLE;
342 msic_dcr_write(msic, MSIC_CTRL_REG, tmp);
345 static int axon_msi_probe(struct platform_device *device)
347 struct device_node *dn = device->dev.of_node;
348 struct axon_msic *msic;
349 unsigned int virq;
350 int dcr_base, dcr_len;
352 pr_devel("axon_msi: setting up dn %s\n", dn->full_name);
354 msic = kzalloc(sizeof(struct axon_msic), GFP_KERNEL);
355 if (!msic) {
356 printk(KERN_ERR "axon_msi: couldn't allocate msic for %s\n",
357 dn->full_name);
358 goto out;
361 dcr_base = dcr_resource_start(dn, 0);
362 dcr_len = dcr_resource_len(dn, 0);
364 if (dcr_base == 0 || dcr_len == 0) {
365 printk(KERN_ERR
366 "axon_msi: couldn't parse dcr properties on %s\n",
367 dn->full_name);
368 goto out_free_msic;
371 msic->dcr_host = dcr_map(dn, dcr_base, dcr_len);
372 if (!DCR_MAP_OK(msic->dcr_host)) {
373 printk(KERN_ERR "axon_msi: dcr_map failed for %s\n",
374 dn->full_name);
375 goto out_free_msic;
378 msic->fifo_virt = dma_alloc_coherent(&device->dev, MSIC_FIFO_SIZE_BYTES,
379 &msic->fifo_phys, GFP_KERNEL);
380 if (!msic->fifo_virt) {
381 printk(KERN_ERR "axon_msi: couldn't allocate fifo for %s\n",
382 dn->full_name);
383 goto out_free_msic;
386 virq = irq_of_parse_and_map(dn, 0);
387 if (virq == NO_IRQ) {
388 printk(KERN_ERR "axon_msi: irq parse and map failed for %s\n",
389 dn->full_name);
390 goto out_free_fifo;
392 memset(msic->fifo_virt, 0xff, MSIC_FIFO_SIZE_BYTES);
394 msic->irq_host = irq_alloc_host(dn, IRQ_HOST_MAP_NOMAP,
395 NR_IRQS, &msic_host_ops, 0);
396 if (!msic->irq_host) {
397 printk(KERN_ERR "axon_msi: couldn't allocate irq_host for %s\n",
398 dn->full_name);
399 goto out_free_fifo;
402 msic->irq_host->host_data = msic;
404 irq_set_handler_data(virq, msic);
405 irq_set_chained_handler(virq, axon_msi_cascade);
406 pr_devel("axon_msi: irq 0x%x setup for axon_msi\n", virq);
408 /* Enable the MSIC hardware */
409 msic_dcr_write(msic, MSIC_BASE_ADDR_HI_REG, msic->fifo_phys >> 32);
410 msic_dcr_write(msic, MSIC_BASE_ADDR_LO_REG,
411 msic->fifo_phys & 0xFFFFFFFF);
412 msic_dcr_write(msic, MSIC_CTRL_REG,
413 MSIC_CTRL_IRQ_ENABLE | MSIC_CTRL_ENABLE |
414 MSIC_CTRL_FIFO_SIZE);
416 msic->read_offset = dcr_read(msic->dcr_host, MSIC_WRITE_OFFSET_REG)
417 & MSIC_FIFO_SIZE_MASK;
419 dev_set_drvdata(&device->dev, msic);
421 ppc_md.setup_msi_irqs = axon_msi_setup_msi_irqs;
422 ppc_md.teardown_msi_irqs = axon_msi_teardown_msi_irqs;
423 ppc_md.msi_check_device = axon_msi_check_device;
425 axon_msi_debug_setup(dn, msic);
427 printk(KERN_DEBUG "axon_msi: setup MSIC on %s\n", dn->full_name);
429 return 0;
431 out_free_fifo:
432 dma_free_coherent(&device->dev, MSIC_FIFO_SIZE_BYTES, msic->fifo_virt,
433 msic->fifo_phys);
434 out_free_msic:
435 kfree(msic);
436 out:
438 return -1;
441 static const struct of_device_id axon_msi_device_id[] = {
443 .compatible = "ibm,axon-msic"
448 static struct platform_driver axon_msi_driver = {
449 .probe = axon_msi_probe,
450 .shutdown = axon_msi_shutdown,
451 .driver = {
452 .name = "axon-msi",
453 .owner = THIS_MODULE,
454 .of_match_table = axon_msi_device_id,
458 static int __init axon_msi_init(void)
460 return platform_driver_register(&axon_msi_driver);
462 subsys_initcall(axon_msi_init);
465 #ifdef DEBUG
466 static int msic_set(void *data, u64 val)
468 struct axon_msic *msic = data;
469 out_le32(msic->trigger, val);
470 return 0;
473 static int msic_get(void *data, u64 *val)
475 *val = 0;
476 return 0;
479 DEFINE_SIMPLE_ATTRIBUTE(fops_msic, msic_get, msic_set, "%llu\n");
481 void axon_msi_debug_setup(struct device_node *dn, struct axon_msic *msic)
483 char name[8];
484 u64 addr;
486 addr = of_translate_address(dn, of_get_property(dn, "reg", NULL));
487 if (addr == OF_BAD_ADDR) {
488 pr_devel("axon_msi: couldn't translate reg property\n");
489 return;
492 msic->trigger = ioremap(addr, 0x4);
493 if (!msic->trigger) {
494 pr_devel("axon_msi: ioremap failed\n");
495 return;
498 snprintf(name, sizeof(name), "msic_%d", of_node_to_nid(dn));
500 if (!debugfs_create_file(name, 0600, powerpc_debugfs_root,
501 msic, &fops_msic)) {
502 pr_devel("axon_msi: debugfs_create_file failed!\n");
503 return;
506 #endif /* DEBUG */