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authorIngo Molnar <mingo@elte.hu>2009-03-27 23:21:18 -0400
committerIngo Molnar <mingo@elte.hu>2009-03-27 23:26:01 -0400
commit82268da1b130f763d22d04f7d016bbf6fc8815c2 (patch)
tree9803f361556d10708313e980428e63a18162e667 /drivers/firewire/fw-iso.c
parent6e15cf04860074ad032e88c306bea656bbdd0f22 (diff)
parent5d80f8e5a9dc9c9a94d4aeaa567e219a808b8a4a (diff)
Merge branch 'linus' into percpu-cpumask-x86-for-linus-2
Conflicts: arch/sparc/kernel/time_64.c drivers/gpu/drm/drm_proc.c Manual merge to resolve build warning due to phys_addr_t type change on x86: drivers/gpu/drm/drm_info.c Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'drivers/firewire/fw-iso.c')
-rw-r--r--drivers/firewire/fw-iso.c227
1 files changed, 198 insertions, 29 deletions
diff --git a/drivers/firewire/fw-iso.c b/drivers/firewire/fw-iso.c
index e14c03dc0065..2baf1007253e 100644
--- a/drivers/firewire/fw-iso.c
+++ b/drivers/firewire/fw-iso.c
@@ -1,5 +1,7 @@
1/* 1/*
2 * Isochronous IO functionality 2 * Isochronous I/O functionality:
3 * - Isochronous DMA context management
4 * - Isochronous bus resource management (channels, bandwidth), client side
3 * 5 *
4 * Copyright (C) 2006 Kristian Hoegsberg <krh@bitplanet.net> 6 * Copyright (C) 2006 Kristian Hoegsberg <krh@bitplanet.net>
5 * 7 *
@@ -18,21 +20,25 @@
18 * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. 20 * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
19 */ 21 */
20 22
21#include <linux/kernel.h>
22#include <linux/module.h>
23#include <linux/dma-mapping.h> 23#include <linux/dma-mapping.h>
24#include <linux/vmalloc.h> 24#include <linux/errno.h>
25#include <linux/firewire-constants.h>
26#include <linux/kernel.h>
25#include <linux/mm.h> 27#include <linux/mm.h>
28#include <linux/spinlock.h>
29#include <linux/vmalloc.h>
26 30
27#include "fw-transaction.h"
28#include "fw-topology.h" 31#include "fw-topology.h"
29#include "fw-device.h" 32#include "fw-transaction.h"
30 33
31int 34/*
32fw_iso_buffer_init(struct fw_iso_buffer *buffer, struct fw_card *card, 35 * Isochronous DMA context management
33 int page_count, enum dma_data_direction direction) 36 */
37
38int fw_iso_buffer_init(struct fw_iso_buffer *buffer, struct fw_card *card,
39 int page_count, enum dma_data_direction direction)
34{ 40{
35 int i, j, retval = -ENOMEM; 41 int i, j;
36 dma_addr_t address; 42 dma_addr_t address;
37 43
38 buffer->page_count = page_count; 44 buffer->page_count = page_count;
@@ -69,19 +75,21 @@ fw_iso_buffer_init(struct fw_iso_buffer *buffer, struct fw_card *card,
69 kfree(buffer->pages); 75 kfree(buffer->pages);
70 out: 76 out:
71 buffer->pages = NULL; 77 buffer->pages = NULL;
72 return retval; 78
79 return -ENOMEM;
73} 80}
74 81
75int fw_iso_buffer_map(struct fw_iso_buffer *buffer, struct vm_area_struct *vma) 82int fw_iso_buffer_map(struct fw_iso_buffer *buffer, struct vm_area_struct *vma)
76{ 83{
77 unsigned long uaddr; 84 unsigned long uaddr;
78 int i, retval; 85 int i, err;
79 86
80 uaddr = vma->vm_start; 87 uaddr = vma->vm_start;
81 for (i = 0; i < buffer->page_count; i++) { 88 for (i = 0; i < buffer->page_count; i++) {
82 retval = vm_insert_page(vma, uaddr, buffer->pages[i]); 89 err = vm_insert_page(vma, uaddr, buffer->pages[i]);
83 if (retval) 90 if (err)
84 return retval; 91 return err;
92
85 uaddr += PAGE_SIZE; 93 uaddr += PAGE_SIZE;
86 } 94 }
87 95
@@ -105,14 +113,14 @@ void fw_iso_buffer_destroy(struct fw_iso_buffer *buffer,
105 buffer->pages = NULL; 113 buffer->pages = NULL;
106} 114}
107 115
108struct fw_iso_context * 116struct fw_iso_context *fw_iso_context_create(struct fw_card *card,
109fw_iso_context_create(struct fw_card *card, int type, 117 int type, int channel, int speed, size_t header_size,
110 int channel, int speed, size_t header_size, 118 fw_iso_callback_t callback, void *callback_data)
111 fw_iso_callback_t callback, void *callback_data)
112{ 119{
113 struct fw_iso_context *ctx; 120 struct fw_iso_context *ctx;
114 121
115 ctx = card->driver->allocate_iso_context(card, type, header_size); 122 ctx = card->driver->allocate_iso_context(card,
123 type, channel, header_size);
116 if (IS_ERR(ctx)) 124 if (IS_ERR(ctx))
117 return ctx; 125 return ctx;
118 126
@@ -134,25 +142,186 @@ void fw_iso_context_destroy(struct fw_iso_context *ctx)
134 card->driver->free_iso_context(ctx); 142 card->driver->free_iso_context(ctx);
135} 143}
136 144
137int 145int fw_iso_context_start(struct fw_iso_context *ctx,
138fw_iso_context_start(struct fw_iso_context *ctx, int cycle, int sync, int tags) 146 int cycle, int sync, int tags)
139{ 147{
140 return ctx->card->driver->start_iso(ctx, cycle, sync, tags); 148 return ctx->card->driver->start_iso(ctx, cycle, sync, tags);
141} 149}
142 150
143int 151int fw_iso_context_queue(struct fw_iso_context *ctx,
144fw_iso_context_queue(struct fw_iso_context *ctx, 152 struct fw_iso_packet *packet,
145 struct fw_iso_packet *packet, 153 struct fw_iso_buffer *buffer,
146 struct fw_iso_buffer *buffer, 154 unsigned long payload)
147 unsigned long payload)
148{ 155{
149 struct fw_card *card = ctx->card; 156 struct fw_card *card = ctx->card;
150 157
151 return card->driver->queue_iso(ctx, packet, buffer, payload); 158 return card->driver->queue_iso(ctx, packet, buffer, payload);
152} 159}
153 160
154int 161int fw_iso_context_stop(struct fw_iso_context *ctx)
155fw_iso_context_stop(struct fw_iso_context *ctx)
156{ 162{
157 return ctx->card->driver->stop_iso(ctx); 163 return ctx->card->driver->stop_iso(ctx);
158} 164}
165
166/*
167 * Isochronous bus resource management (channels, bandwidth), client side
168 */
169
170static int manage_bandwidth(struct fw_card *card, int irm_id, int generation,
171 int bandwidth, bool allocate)
172{
173 __be32 data[2];
174 int try, new, old = allocate ? BANDWIDTH_AVAILABLE_INITIAL : 0;
175
176 /*
177 * On a 1394a IRM with low contention, try < 1 is enough.
178 * On a 1394-1995 IRM, we need at least try < 2.
179 * Let's just do try < 5.
180 */
181 for (try = 0; try < 5; try++) {
182 new = allocate ? old - bandwidth : old + bandwidth;
183 if (new < 0 || new > BANDWIDTH_AVAILABLE_INITIAL)
184 break;
185
186 data[0] = cpu_to_be32(old);
187 data[1] = cpu_to_be32(new);
188 switch (fw_run_transaction(card, TCODE_LOCK_COMPARE_SWAP,
189 irm_id, generation, SCODE_100,
190 CSR_REGISTER_BASE + CSR_BANDWIDTH_AVAILABLE,
191 data, sizeof(data))) {
192 case RCODE_GENERATION:
193 /* A generation change frees all bandwidth. */
194 return allocate ? -EAGAIN : bandwidth;
195
196 case RCODE_COMPLETE:
197 if (be32_to_cpup(data) == old)
198 return bandwidth;
199
200 old = be32_to_cpup(data);
201 /* Fall through. */
202 }
203 }
204
205 return -EIO;
206}
207
208static int manage_channel(struct fw_card *card, int irm_id, int generation,
209 u32 channels_mask, u64 offset, bool allocate)
210{
211 __be32 data[2], c, all, old;
212 int i, retry = 5;
213
214 old = all = allocate ? cpu_to_be32(~0) : 0;
215
216 for (i = 0; i < 32; i++) {
217 if (!(channels_mask & 1 << i))
218 continue;
219
220 c = cpu_to_be32(1 << (31 - i));
221 if ((old & c) != (all & c))
222 continue;
223
224 data[0] = old;
225 data[1] = old ^ c;
226 switch (fw_run_transaction(card, TCODE_LOCK_COMPARE_SWAP,
227 irm_id, generation, SCODE_100,
228 offset, data, sizeof(data))) {
229 case RCODE_GENERATION:
230 /* A generation change frees all channels. */
231 return allocate ? -EAGAIN : i;
232
233 case RCODE_COMPLETE:
234 if (data[0] == old)
235 return i;
236
237 old = data[0];
238
239 /* Is the IRM 1394a-2000 compliant? */
240 if ((data[0] & c) == (data[1] & c))
241 continue;
242
243 /* 1394-1995 IRM, fall through to retry. */
244 default:
245 if (retry--)
246 i--;
247 }
248 }
249
250 return -EIO;
251}
252
253static void deallocate_channel(struct fw_card *card, int irm_id,
254 int generation, int channel)
255{
256 u32 mask;
257 u64 offset;
258
259 mask = channel < 32 ? 1 << channel : 1 << (channel - 32);
260 offset = channel < 32 ? CSR_REGISTER_BASE + CSR_CHANNELS_AVAILABLE_HI :
261 CSR_REGISTER_BASE + CSR_CHANNELS_AVAILABLE_LO;
262
263 manage_channel(card, irm_id, generation, mask, offset, false);
264}
265
266/**
267 * fw_iso_resource_manage - Allocate or deallocate a channel and/or bandwidth
268 *
269 * In parameters: card, generation, channels_mask, bandwidth, allocate
270 * Out parameters: channel, bandwidth
271 * This function blocks (sleeps) during communication with the IRM.
272 *
273 * Allocates or deallocates at most one channel out of channels_mask.
274 * channels_mask is a bitfield with MSB for channel 63 and LSB for channel 0.
275 * (Note, the IRM's CHANNELS_AVAILABLE is a big-endian bitfield with MSB for
276 * channel 0 and LSB for channel 63.)
277 * Allocates or deallocates as many bandwidth allocation units as specified.
278 *
279 * Returns channel < 0 if no channel was allocated or deallocated.
280 * Returns bandwidth = 0 if no bandwidth was allocated or deallocated.
281 *
282 * If generation is stale, deallocations succeed but allocations fail with
283 * channel = -EAGAIN.
284 *
285 * If channel allocation fails, no bandwidth will be allocated either.
286 * If bandwidth allocation fails, no channel will be allocated either.
287 * But deallocations of channel and bandwidth are tried independently
288 * of each other's success.
289 */
290void fw_iso_resource_manage(struct fw_card *card, int generation,
291 u64 channels_mask, int *channel, int *bandwidth,
292 bool allocate)
293{
294 u32 channels_hi = channels_mask; /* channels 31...0 */
295 u32 channels_lo = channels_mask >> 32; /* channels 63...32 */
296 int irm_id, ret, c = -EINVAL;
297
298 spin_lock_irq(&card->lock);
299 irm_id = card->irm_node->node_id;
300 spin_unlock_irq(&card->lock);
301
302 if (channels_hi)
303 c = manage_channel(card, irm_id, generation, channels_hi,
304 CSR_REGISTER_BASE + CSR_CHANNELS_AVAILABLE_HI, allocate);
305 if (channels_lo && c < 0) {
306 c = manage_channel(card, irm_id, generation, channels_lo,
307 CSR_REGISTER_BASE + CSR_CHANNELS_AVAILABLE_LO, allocate);
308 if (c >= 0)
309 c += 32;
310 }
311 *channel = c;
312
313 if (allocate && channels_mask != 0 && c < 0)
314 *bandwidth = 0;
315
316 if (*bandwidth == 0)
317 return;
318
319 ret = manage_bandwidth(card, irm_id, generation, *bandwidth, allocate);
320 if (ret < 0)
321 *bandwidth = 0;
322
323 if (allocate && ret < 0 && c >= 0) {
324 deallocate_channel(card, irm_id, generation, c);
325 *channel = ret;
326 }
327}