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12#include <linux/dmaengine.h>
13#include <linux/dma-mapping.h>
14#include <linux/err.h>
15#include <linux/init.h>
16#include <linux/list.h>
17#include <linux/module.h>
18#include <linux/platform_device.h>
19#include <linux/slab.h>
20#include <linux/spinlock.h>
21#include <linux/irq.h>
22#include <linux/clk.h>
23
24#include <asm/mach-jz4740/dma.h>
25
26#include "virt-dma.h"
27
28#define JZ_DMA_NR_CHANS 6
29
30#define JZ_REG_DMA_SRC_ADDR(x) (0x00 + (x) * 0x20)
31#define JZ_REG_DMA_DST_ADDR(x) (0x04 + (x) * 0x20)
32#define JZ_REG_DMA_TRANSFER_COUNT(x) (0x08 + (x) * 0x20)
33#define JZ_REG_DMA_REQ_TYPE(x) (0x0C + (x) * 0x20)
34#define JZ_REG_DMA_STATUS_CTRL(x) (0x10 + (x) * 0x20)
35#define JZ_REG_DMA_CMD(x) (0x14 + (x) * 0x20)
36#define JZ_REG_DMA_DESC_ADDR(x) (0x18 + (x) * 0x20)
37
38#define JZ_REG_DMA_CTRL 0x300
39#define JZ_REG_DMA_IRQ 0x304
40#define JZ_REG_DMA_DOORBELL 0x308
41#define JZ_REG_DMA_DOORBELL_SET 0x30C
42
43#define JZ_DMA_STATUS_CTRL_NO_DESC BIT(31)
44#define JZ_DMA_STATUS_CTRL_DESC_INV BIT(6)
45#define JZ_DMA_STATUS_CTRL_ADDR_ERR BIT(4)
46#define JZ_DMA_STATUS_CTRL_TRANSFER_DONE BIT(3)
47#define JZ_DMA_STATUS_CTRL_HALT BIT(2)
48#define JZ_DMA_STATUS_CTRL_COUNT_TERMINATE BIT(1)
49#define JZ_DMA_STATUS_CTRL_ENABLE BIT(0)
50
51#define JZ_DMA_CMD_SRC_INC BIT(23)
52#define JZ_DMA_CMD_DST_INC BIT(22)
53#define JZ_DMA_CMD_RDIL_MASK (0xf << 16)
54#define JZ_DMA_CMD_SRC_WIDTH_MASK (0x3 << 14)
55#define JZ_DMA_CMD_DST_WIDTH_MASK (0x3 << 12)
56#define JZ_DMA_CMD_INTERVAL_LENGTH_MASK (0x7 << 8)
57#define JZ_DMA_CMD_BLOCK_MODE BIT(7)
58#define JZ_DMA_CMD_DESC_VALID BIT(4)
59#define JZ_DMA_CMD_DESC_VALID_MODE BIT(3)
60#define JZ_DMA_CMD_VALID_IRQ_ENABLE BIT(2)
61#define JZ_DMA_CMD_TRANSFER_IRQ_ENABLE BIT(1)
62#define JZ_DMA_CMD_LINK_ENABLE BIT(0)
63
64#define JZ_DMA_CMD_FLAGS_OFFSET 22
65#define JZ_DMA_CMD_RDIL_OFFSET 16
66#define JZ_DMA_CMD_SRC_WIDTH_OFFSET 14
67#define JZ_DMA_CMD_DST_WIDTH_OFFSET 12
68#define JZ_DMA_CMD_TRANSFER_SIZE_OFFSET 8
69#define JZ_DMA_CMD_MODE_OFFSET 7
70
71#define JZ_DMA_CTRL_PRIORITY_MASK (0x3 << 8)
72#define JZ_DMA_CTRL_HALT BIT(3)
73#define JZ_DMA_CTRL_ADDRESS_ERROR BIT(2)
74#define JZ_DMA_CTRL_ENABLE BIT(0)
75
76enum jz4740_dma_width {
77 JZ4740_DMA_WIDTH_32BIT = 0,
78 JZ4740_DMA_WIDTH_8BIT = 1,
79 JZ4740_DMA_WIDTH_16BIT = 2,
80};
81
82enum jz4740_dma_transfer_size {
83 JZ4740_DMA_TRANSFER_SIZE_4BYTE = 0,
84 JZ4740_DMA_TRANSFER_SIZE_1BYTE = 1,
85 JZ4740_DMA_TRANSFER_SIZE_2BYTE = 2,
86 JZ4740_DMA_TRANSFER_SIZE_16BYTE = 3,
87 JZ4740_DMA_TRANSFER_SIZE_32BYTE = 4,
88};
89
90enum jz4740_dma_flags {
91 JZ4740_DMA_SRC_AUTOINC = 0x2,
92 JZ4740_DMA_DST_AUTOINC = 0x1,
93};
94
95enum jz4740_dma_mode {
96 JZ4740_DMA_MODE_SINGLE = 0,
97 JZ4740_DMA_MODE_BLOCK = 1,
98};
99
100struct jz4740_dma_sg {
101 dma_addr_t addr;
102 unsigned int len;
103};
104
105struct jz4740_dma_desc {
106 struct virt_dma_desc vdesc;
107
108 enum dma_transfer_direction direction;
109 bool cyclic;
110
111 unsigned int num_sgs;
112 struct jz4740_dma_sg sg[];
113};
114
115struct jz4740_dmaengine_chan {
116 struct virt_dma_chan vchan;
117 unsigned int id;
118
119 dma_addr_t fifo_addr;
120 unsigned int transfer_shift;
121
122 struct jz4740_dma_desc *desc;
123 unsigned int next_sg;
124};
125
126struct jz4740_dma_dev {
127 struct dma_device ddev;
128 void __iomem *base;
129 struct clk *clk;
130
131 struct jz4740_dmaengine_chan chan[JZ_DMA_NR_CHANS];
132};
133
134static struct jz4740_dma_dev *jz4740_dma_chan_get_dev(
135 struct jz4740_dmaengine_chan *chan)
136{
137 return container_of(chan->vchan.chan.device, struct jz4740_dma_dev,
138 ddev);
139}
140
141static struct jz4740_dmaengine_chan *to_jz4740_dma_chan(struct dma_chan *c)
142{
143 return container_of(c, struct jz4740_dmaengine_chan, vchan.chan);
144}
145
146static struct jz4740_dma_desc *to_jz4740_dma_desc(struct virt_dma_desc *vdesc)
147{
148 return container_of(vdesc, struct jz4740_dma_desc, vdesc);
149}
150
151static inline uint32_t jz4740_dma_read(struct jz4740_dma_dev *dmadev,
152 unsigned int reg)
153{
154 return readl(dmadev->base + reg);
155}
156
157static inline void jz4740_dma_write(struct jz4740_dma_dev *dmadev,
158 unsigned reg, uint32_t val)
159{
160 writel(val, dmadev->base + reg);
161}
162
163static inline void jz4740_dma_write_mask(struct jz4740_dma_dev *dmadev,
164 unsigned int reg, uint32_t val, uint32_t mask)
165{
166 uint32_t tmp;
167
168 tmp = jz4740_dma_read(dmadev, reg);
169 tmp &= ~mask;
170 tmp |= val;
171 jz4740_dma_write(dmadev, reg, tmp);
172}
173
174static struct jz4740_dma_desc *jz4740_dma_alloc_desc(unsigned int num_sgs)
175{
176 return kzalloc(sizeof(struct jz4740_dma_desc) +
177 sizeof(struct jz4740_dma_sg) * num_sgs, GFP_ATOMIC);
178}
179
180static enum jz4740_dma_width jz4740_dma_width(enum dma_slave_buswidth width)
181{
182 switch (width) {
183 case DMA_SLAVE_BUSWIDTH_1_BYTE:
184 return JZ4740_DMA_WIDTH_8BIT;
185 case DMA_SLAVE_BUSWIDTH_2_BYTES:
186 return JZ4740_DMA_WIDTH_16BIT;
187 case DMA_SLAVE_BUSWIDTH_4_BYTES:
188 return JZ4740_DMA_WIDTH_32BIT;
189 default:
190 return JZ4740_DMA_WIDTH_32BIT;
191 }
192}
193
194static enum jz4740_dma_transfer_size jz4740_dma_maxburst(u32 maxburst)
195{
196 if (maxburst <= 1)
197 return JZ4740_DMA_TRANSFER_SIZE_1BYTE;
198 else if (maxburst <= 3)
199 return JZ4740_DMA_TRANSFER_SIZE_2BYTE;
200 else if (maxburst <= 15)
201 return JZ4740_DMA_TRANSFER_SIZE_4BYTE;
202 else if (maxburst <= 31)
203 return JZ4740_DMA_TRANSFER_SIZE_16BYTE;
204
205 return JZ4740_DMA_TRANSFER_SIZE_32BYTE;
206}
207
208static int jz4740_dma_slave_config(struct dma_chan *c,
209 struct dma_slave_config *config)
210{
211 struct jz4740_dmaengine_chan *chan = to_jz4740_dma_chan(c);
212 struct jz4740_dma_dev *dmadev = jz4740_dma_chan_get_dev(chan);
213 enum jz4740_dma_width src_width;
214 enum jz4740_dma_width dst_width;
215 enum jz4740_dma_transfer_size transfer_size;
216 enum jz4740_dma_flags flags;
217 uint32_t cmd;
218
219 switch (config->direction) {
220 case DMA_MEM_TO_DEV:
221 flags = JZ4740_DMA_SRC_AUTOINC;
222 transfer_size = jz4740_dma_maxburst(config->dst_maxburst);
223 chan->fifo_addr = config->dst_addr;
224 break;
225 case DMA_DEV_TO_MEM:
226 flags = JZ4740_DMA_DST_AUTOINC;
227 transfer_size = jz4740_dma_maxburst(config->src_maxburst);
228 chan->fifo_addr = config->src_addr;
229 break;
230 default:
231 return -EINVAL;
232 }
233
234 src_width = jz4740_dma_width(config->src_addr_width);
235 dst_width = jz4740_dma_width(config->dst_addr_width);
236
237 switch (transfer_size) {
238 case JZ4740_DMA_TRANSFER_SIZE_2BYTE:
239 chan->transfer_shift = 1;
240 break;
241 case JZ4740_DMA_TRANSFER_SIZE_4BYTE:
242 chan->transfer_shift = 2;
243 break;
244 case JZ4740_DMA_TRANSFER_SIZE_16BYTE:
245 chan->transfer_shift = 4;
246 break;
247 case JZ4740_DMA_TRANSFER_SIZE_32BYTE:
248 chan->transfer_shift = 5;
249 break;
250 default:
251 chan->transfer_shift = 0;
252 break;
253 }
254
255 cmd = flags << JZ_DMA_CMD_FLAGS_OFFSET;
256 cmd |= src_width << JZ_DMA_CMD_SRC_WIDTH_OFFSET;
257 cmd |= dst_width << JZ_DMA_CMD_DST_WIDTH_OFFSET;
258 cmd |= transfer_size << JZ_DMA_CMD_TRANSFER_SIZE_OFFSET;
259 cmd |= JZ4740_DMA_MODE_SINGLE << JZ_DMA_CMD_MODE_OFFSET;
260 cmd |= JZ_DMA_CMD_TRANSFER_IRQ_ENABLE;
261
262 jz4740_dma_write(dmadev, JZ_REG_DMA_CMD(chan->id), cmd);
263 jz4740_dma_write(dmadev, JZ_REG_DMA_STATUS_CTRL(chan->id), 0);
264 jz4740_dma_write(dmadev, JZ_REG_DMA_REQ_TYPE(chan->id),
265 config->slave_id);
266
267 return 0;
268}
269
270static int jz4740_dma_terminate_all(struct dma_chan *c)
271{
272 struct jz4740_dmaengine_chan *chan = to_jz4740_dma_chan(c);
273 struct jz4740_dma_dev *dmadev = jz4740_dma_chan_get_dev(chan);
274 unsigned long flags;
275 LIST_HEAD(head);
276
277 spin_lock_irqsave(&chan->vchan.lock, flags);
278 jz4740_dma_write_mask(dmadev, JZ_REG_DMA_STATUS_CTRL(chan->id), 0,
279 JZ_DMA_STATUS_CTRL_ENABLE);
280 chan->desc = NULL;
281 vchan_get_all_descriptors(&chan->vchan, &head);
282 spin_unlock_irqrestore(&chan->vchan.lock, flags);
283
284 vchan_dma_desc_free_list(&chan->vchan, &head);
285
286 return 0;
287}
288
289static int jz4740_dma_start_transfer(struct jz4740_dmaengine_chan *chan)
290{
291 struct jz4740_dma_dev *dmadev = jz4740_dma_chan_get_dev(chan);
292 dma_addr_t src_addr, dst_addr;
293 struct virt_dma_desc *vdesc;
294 struct jz4740_dma_sg *sg;
295
296 jz4740_dma_write_mask(dmadev, JZ_REG_DMA_STATUS_CTRL(chan->id), 0,
297 JZ_DMA_STATUS_CTRL_ENABLE);
298
299 if (!chan->desc) {
300 vdesc = vchan_next_desc(&chan->vchan);
301 if (!vdesc)
302 return 0;
303 chan->desc = to_jz4740_dma_desc(vdesc);
304 chan->next_sg = 0;
305 }
306
307 if (chan->next_sg == chan->desc->num_sgs)
308 chan->next_sg = 0;
309
310 sg = &chan->desc->sg[chan->next_sg];
311
312 if (chan->desc->direction == DMA_MEM_TO_DEV) {
313 src_addr = sg->addr;
314 dst_addr = chan->fifo_addr;
315 } else {
316 src_addr = chan->fifo_addr;
317 dst_addr = sg->addr;
318 }
319 jz4740_dma_write(dmadev, JZ_REG_DMA_SRC_ADDR(chan->id), src_addr);
320 jz4740_dma_write(dmadev, JZ_REG_DMA_DST_ADDR(chan->id), dst_addr);
321 jz4740_dma_write(dmadev, JZ_REG_DMA_TRANSFER_COUNT(chan->id),
322 sg->len >> chan->transfer_shift);
323
324 chan->next_sg++;
325
326 jz4740_dma_write_mask(dmadev, JZ_REG_DMA_STATUS_CTRL(chan->id),
327 JZ_DMA_STATUS_CTRL_NO_DESC | JZ_DMA_STATUS_CTRL_ENABLE,
328 JZ_DMA_STATUS_CTRL_HALT | JZ_DMA_STATUS_CTRL_NO_DESC |
329 JZ_DMA_STATUS_CTRL_ENABLE);
330
331 jz4740_dma_write_mask(dmadev, JZ_REG_DMA_CTRL,
332 JZ_DMA_CTRL_ENABLE,
333 JZ_DMA_CTRL_HALT | JZ_DMA_CTRL_ENABLE);
334
335 return 0;
336}
337
338static void jz4740_dma_chan_irq(struct jz4740_dmaengine_chan *chan)
339{
340 spin_lock(&chan->vchan.lock);
341 if (chan->desc) {
342 if (chan->desc->cyclic) {
343 vchan_cyclic_callback(&chan->desc->vdesc);
344 } else {
345 if (chan->next_sg == chan->desc->num_sgs) {
346 list_del(&chan->desc->vdesc.node);
347 vchan_cookie_complete(&chan->desc->vdesc);
348 chan->desc = NULL;
349 }
350 }
351 }
352 jz4740_dma_start_transfer(chan);
353 spin_unlock(&chan->vchan.lock);
354}
355
356static irqreturn_t jz4740_dma_irq(int irq, void *devid)
357{
358 struct jz4740_dma_dev *dmadev = devid;
359 uint32_t irq_status;
360 unsigned int i;
361
362 irq_status = readl(dmadev->base + JZ_REG_DMA_IRQ);
363
364 for (i = 0; i < 6; ++i) {
365 if (irq_status & (1 << i)) {
366 jz4740_dma_write_mask(dmadev,
367 JZ_REG_DMA_STATUS_CTRL(i), 0,
368 JZ_DMA_STATUS_CTRL_ENABLE |
369 JZ_DMA_STATUS_CTRL_TRANSFER_DONE);
370
371 jz4740_dma_chan_irq(&dmadev->chan[i]);
372 }
373 }
374
375 return IRQ_HANDLED;
376}
377
378static void jz4740_dma_issue_pending(struct dma_chan *c)
379{
380 struct jz4740_dmaengine_chan *chan = to_jz4740_dma_chan(c);
381 unsigned long flags;
382
383 spin_lock_irqsave(&chan->vchan.lock, flags);
384 if (vchan_issue_pending(&chan->vchan) && !chan->desc)
385 jz4740_dma_start_transfer(chan);
386 spin_unlock_irqrestore(&chan->vchan.lock, flags);
387}
388
389static struct dma_async_tx_descriptor *jz4740_dma_prep_slave_sg(
390 struct dma_chan *c, struct scatterlist *sgl,
391 unsigned int sg_len, enum dma_transfer_direction direction,
392 unsigned long flags, void *context)
393{
394 struct jz4740_dmaengine_chan *chan = to_jz4740_dma_chan(c);
395 struct jz4740_dma_desc *desc;
396 struct scatterlist *sg;
397 unsigned int i;
398
399 desc = jz4740_dma_alloc_desc(sg_len);
400 if (!desc)
401 return NULL;
402
403 for_each_sg(sgl, sg, sg_len, i) {
404 desc->sg[i].addr = sg_dma_address(sg);
405 desc->sg[i].len = sg_dma_len(sg);
406 }
407
408 desc->num_sgs = sg_len;
409 desc->direction = direction;
410 desc->cyclic = false;
411
412 return vchan_tx_prep(&chan->vchan, &desc->vdesc, flags);
413}
414
415static struct dma_async_tx_descriptor *jz4740_dma_prep_dma_cyclic(
416 struct dma_chan *c, dma_addr_t buf_addr, size_t buf_len,
417 size_t period_len, enum dma_transfer_direction direction,
418 unsigned long flags)
419{
420 struct jz4740_dmaengine_chan *chan = to_jz4740_dma_chan(c);
421 struct jz4740_dma_desc *desc;
422 unsigned int num_periods, i;
423
424 if (buf_len % period_len)
425 return NULL;
426
427 num_periods = buf_len / period_len;
428
429 desc = jz4740_dma_alloc_desc(num_periods);
430 if (!desc)
431 return NULL;
432
433 for (i = 0; i < num_periods; i++) {
434 desc->sg[i].addr = buf_addr;
435 desc->sg[i].len = period_len;
436 buf_addr += period_len;
437 }
438
439 desc->num_sgs = num_periods;
440 desc->direction = direction;
441 desc->cyclic = true;
442
443 return vchan_tx_prep(&chan->vchan, &desc->vdesc, flags);
444}
445
446static size_t jz4740_dma_desc_residue(struct jz4740_dmaengine_chan *chan,
447 struct jz4740_dma_desc *desc, unsigned int next_sg)
448{
449 struct jz4740_dma_dev *dmadev = jz4740_dma_chan_get_dev(chan);
450 unsigned int residue, count;
451 unsigned int i;
452
453 residue = 0;
454
455 for (i = next_sg; i < desc->num_sgs; i++)
456 residue += desc->sg[i].len;
457
458 if (next_sg != 0) {
459 count = jz4740_dma_read(dmadev,
460 JZ_REG_DMA_TRANSFER_COUNT(chan->id));
461 residue += count << chan->transfer_shift;
462 }
463
464 return residue;
465}
466
467static enum dma_status jz4740_dma_tx_status(struct dma_chan *c,
468 dma_cookie_t cookie, struct dma_tx_state *state)
469{
470 struct jz4740_dmaengine_chan *chan = to_jz4740_dma_chan(c);
471 struct virt_dma_desc *vdesc;
472 enum dma_status status;
473 unsigned long flags;
474
475 status = dma_cookie_status(c, cookie, state);
476 if (status == DMA_COMPLETE || !state)
477 return status;
478
479 spin_lock_irqsave(&chan->vchan.lock, flags);
480 vdesc = vchan_find_desc(&chan->vchan, cookie);
481 if (cookie == chan->desc->vdesc.tx.cookie) {
482 state->residue = jz4740_dma_desc_residue(chan, chan->desc,
483 chan->next_sg);
484 } else if (vdesc) {
485 state->residue = jz4740_dma_desc_residue(chan,
486 to_jz4740_dma_desc(vdesc), 0);
487 } else {
488 state->residue = 0;
489 }
490 spin_unlock_irqrestore(&chan->vchan.lock, flags);
491
492 return status;
493}
494
495static void jz4740_dma_free_chan_resources(struct dma_chan *c)
496{
497 vchan_free_chan_resources(to_virt_chan(c));
498}
499
500static void jz4740_dma_desc_free(struct virt_dma_desc *vdesc)
501{
502 kfree(container_of(vdesc, struct jz4740_dma_desc, vdesc));
503}
504
505#define JZ4740_DMA_BUSWIDTHS (BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) | \
506 BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) | BIT(DMA_SLAVE_BUSWIDTH_4_BYTES))
507
508static int jz4740_dma_probe(struct platform_device *pdev)
509{
510 struct jz4740_dmaengine_chan *chan;
511 struct jz4740_dma_dev *dmadev;
512 struct dma_device *dd;
513 unsigned int i;
514 struct resource *res;
515 int ret;
516 int irq;
517
518 dmadev = devm_kzalloc(&pdev->dev, sizeof(*dmadev), GFP_KERNEL);
519 if (!dmadev)
520 return -EINVAL;
521
522 dd = &dmadev->ddev;
523
524 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
525 dmadev->base = devm_ioremap_resource(&pdev->dev, res);
526 if (IS_ERR(dmadev->base))
527 return PTR_ERR(dmadev->base);
528
529 dmadev->clk = clk_get(&pdev->dev, "dma");
530 if (IS_ERR(dmadev->clk))
531 return PTR_ERR(dmadev->clk);
532
533 clk_prepare_enable(dmadev->clk);
534
535 dma_cap_set(DMA_SLAVE, dd->cap_mask);
536 dma_cap_set(DMA_CYCLIC, dd->cap_mask);
537 dd->device_free_chan_resources = jz4740_dma_free_chan_resources;
538 dd->device_tx_status = jz4740_dma_tx_status;
539 dd->device_issue_pending = jz4740_dma_issue_pending;
540 dd->device_prep_slave_sg = jz4740_dma_prep_slave_sg;
541 dd->device_prep_dma_cyclic = jz4740_dma_prep_dma_cyclic;
542 dd->device_config = jz4740_dma_slave_config;
543 dd->device_terminate_all = jz4740_dma_terminate_all;
544 dd->src_addr_widths = JZ4740_DMA_BUSWIDTHS;
545 dd->dst_addr_widths = JZ4740_DMA_BUSWIDTHS;
546 dd->directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV);
547 dd->residue_granularity = DMA_RESIDUE_GRANULARITY_BURST;
548 dd->dev = &pdev->dev;
549 INIT_LIST_HEAD(&dd->channels);
550
551 for (i = 0; i < JZ_DMA_NR_CHANS; i++) {
552 chan = &dmadev->chan[i];
553 chan->id = i;
554 chan->vchan.desc_free = jz4740_dma_desc_free;
555 vchan_init(&chan->vchan, dd);
556 }
557
558 ret = dma_async_device_register(dd);
559 if (ret)
560 return ret;
561
562 irq = platform_get_irq(pdev, 0);
563 ret = request_irq(irq, jz4740_dma_irq, 0, dev_name(&pdev->dev), dmadev);
564 if (ret)
565 goto err_unregister;
566
567 platform_set_drvdata(pdev, dmadev);
568
569 return 0;
570
571err_unregister:
572 dma_async_device_unregister(dd);
573 return ret;
574}
575
576static int jz4740_dma_remove(struct platform_device *pdev)
577{
578 struct jz4740_dma_dev *dmadev = platform_get_drvdata(pdev);
579 int irq = platform_get_irq(pdev, 0);
580
581 free_irq(irq, dmadev);
582 dma_async_device_unregister(&dmadev->ddev);
583 clk_disable_unprepare(dmadev->clk);
584
585 return 0;
586}
587
588static struct platform_driver jz4740_dma_driver = {
589 .probe = jz4740_dma_probe,
590 .remove = jz4740_dma_remove,
591 .driver = {
592 .name = "jz4740-dma",
593 },
594};
595module_platform_driver(jz4740_dma_driver);
596
597MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
598MODULE_DESCRIPTION("JZ4740 DMA driver");
599MODULE_LICENSE("GPL v2");
600
