xref: /linux/drivers/net/wan/ixp4xx_hss.c (revision 09aa9aabdcc4966270b031816a16d4641fb45dfa)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Intel IXP4xx HSS (synchronous serial port) driver for Linux
4  *
5  * Copyright (C) 2007-2008 Krzysztof Hałasa <khc@pm.waw.pl>
6  */
7 
8 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
9 
10 #include <linux/module.h>
11 #include <linux/bitops.h>
12 #include <linux/cdev.h>
13 #include <linux/dma-mapping.h>
14 #include <linux/dmapool.h>
15 #include <linux/fs.h>
16 #include <linux/hdlc.h>
17 #include <linux/io.h>
18 #include <linux/kernel.h>
19 #include <linux/platform_device.h>
20 #include <linux/platform_data/wan_ixp4xx_hss.h>
21 #include <linux/poll.h>
22 #include <linux/slab.h>
23 #include <linux/soc/ixp4xx/npe.h>
24 #include <linux/soc/ixp4xx/qmgr.h>
25 #include <linux/soc/ixp4xx/cpu.h>
26 
27 #define DEBUG_DESC		0
28 #define DEBUG_RX		0
29 #define DEBUG_TX		0
30 #define DEBUG_PKT_BYTES		0
31 #define DEBUG_CLOSE		0
32 
33 #define DRV_NAME		"ixp4xx_hss"
34 
35 #define PKT_EXTRA_FLAGS		0 /* orig 1 */
36 #define PKT_NUM_PIPES		1 /* 1, 2 or 4 */
37 #define PKT_PIPE_FIFO_SIZEW	4 /* total 4 dwords per HSS */
38 
39 #define RX_DESCS		16 /* also length of all RX queues */
40 #define TX_DESCS		16 /* also length of all TX queues */
41 
42 #define POOL_ALLOC_SIZE		(sizeof(struct desc) * (RX_DESCS + TX_DESCS))
43 #define RX_SIZE			(HDLC_MAX_MRU + 4) /* NPE needs more space */
44 #define MAX_CLOSE_WAIT		1000 /* microseconds */
45 #define HSS_COUNT		2
46 #define FRAME_SIZE		256 /* doesn't matter at this point */
47 #define FRAME_OFFSET		0
48 #define MAX_CHANNELS		(FRAME_SIZE / 8)
49 
50 #define NAPI_WEIGHT		16
51 
52 /* Queue IDs */
53 #define HSS0_CHL_RXTRIG_QUEUE	12	/* orig size = 32 dwords */
54 #define HSS0_PKT_RX_QUEUE	13	/* orig size = 32 dwords */
55 #define HSS0_PKT_TX0_QUEUE	14	/* orig size = 16 dwords */
56 #define HSS0_PKT_TX1_QUEUE	15
57 #define HSS0_PKT_TX2_QUEUE	16
58 #define HSS0_PKT_TX3_QUEUE	17
59 #define HSS0_PKT_RXFREE0_QUEUE	18	/* orig size = 16 dwords */
60 #define HSS0_PKT_RXFREE1_QUEUE	19
61 #define HSS0_PKT_RXFREE2_QUEUE	20
62 #define HSS0_PKT_RXFREE3_QUEUE	21
63 #define HSS0_PKT_TXDONE_QUEUE	22	/* orig size = 64 dwords */
64 
65 #define HSS1_CHL_RXTRIG_QUEUE	10
66 #define HSS1_PKT_RX_QUEUE	0
67 #define HSS1_PKT_TX0_QUEUE	5
68 #define HSS1_PKT_TX1_QUEUE	6
69 #define HSS1_PKT_TX2_QUEUE	7
70 #define HSS1_PKT_TX3_QUEUE	8
71 #define HSS1_PKT_RXFREE0_QUEUE	1
72 #define HSS1_PKT_RXFREE1_QUEUE	2
73 #define HSS1_PKT_RXFREE2_QUEUE	3
74 #define HSS1_PKT_RXFREE3_QUEUE	4
75 #define HSS1_PKT_TXDONE_QUEUE	9
76 
77 #define NPE_PKT_MODE_HDLC		0
78 #define NPE_PKT_MODE_RAW		1
79 #define NPE_PKT_MODE_56KMODE		2
80 #define NPE_PKT_MODE_56KENDIAN_MSB	4
81 
82 /* PKT_PIPE_HDLC_CFG_WRITE flags */
83 #define PKT_HDLC_IDLE_ONES		0x1 /* default = flags */
84 #define PKT_HDLC_CRC_32			0x2 /* default = CRC-16 */
85 #define PKT_HDLC_MSB_ENDIAN		0x4 /* default = LE */
86 
87 
88 /* hss_config, PCRs */
89 /* Frame sync sampling, default = active low */
90 #define PCR_FRM_SYNC_ACTIVE_HIGH	0x40000000
91 #define PCR_FRM_SYNC_FALLINGEDGE	0x80000000
92 #define PCR_FRM_SYNC_RISINGEDGE		0xC0000000
93 
94 /* Frame sync pin: input (default) or output generated off a given clk edge */
95 #define PCR_FRM_SYNC_OUTPUT_FALLING	0x20000000
96 #define PCR_FRM_SYNC_OUTPUT_RISING	0x30000000
97 
98 /* Frame and data clock sampling on edge, default = falling */
99 #define PCR_FCLK_EDGE_RISING		0x08000000
100 #define PCR_DCLK_EDGE_RISING		0x04000000
101 
102 /* Clock direction, default = input */
103 #define PCR_SYNC_CLK_DIR_OUTPUT		0x02000000
104 
105 /* Generate/Receive frame pulses, default = enabled */
106 #define PCR_FRM_PULSE_DISABLED		0x01000000
107 
108  /* Data rate is full (default) or half the configured clk speed */
109 #define PCR_HALF_CLK_RATE		0x00200000
110 
111 /* Invert data between NPE and HSS FIFOs? (default = no) */
112 #define PCR_DATA_POLARITY_INVERT	0x00100000
113 
114 /* TX/RX endianness, default = LSB */
115 #define PCR_MSB_ENDIAN			0x00080000
116 
117 /* Normal (default) / open drain mode (TX only) */
118 #define PCR_TX_PINS_OPEN_DRAIN		0x00040000
119 
120 /* No framing bit transmitted and expected on RX? (default = framing bit) */
121 #define PCR_SOF_NO_FBIT			0x00020000
122 
123 /* Drive data pins? */
124 #define PCR_TX_DATA_ENABLE		0x00010000
125 
126 /* Voice 56k type: drive the data pins low (default), high, high Z */
127 #define PCR_TX_V56K_HIGH		0x00002000
128 #define PCR_TX_V56K_HIGH_IMP		0x00004000
129 
130 /* Unassigned type: drive the data pins low (default), high, high Z */
131 #define PCR_TX_UNASS_HIGH		0x00000800
132 #define PCR_TX_UNASS_HIGH_IMP		0x00001000
133 
134 /* T1 @ 1.544MHz only: Fbit dictated in FIFO (default) or high Z */
135 #define PCR_TX_FB_HIGH_IMP		0x00000400
136 
137 /* 56k data endiannes - which bit unused: high (default) or low */
138 #define PCR_TX_56KE_BIT_0_UNUSED	0x00000200
139 
140 /* 56k data transmission type: 32/8 bit data (default) or 56K data */
141 #define PCR_TX_56KS_56K_DATA		0x00000100
142 
143 /* hss_config, cCR */
144 /* Number of packetized clients, default = 1 */
145 #define CCR_NPE_HFIFO_2_HDLC		0x04000000
146 #define CCR_NPE_HFIFO_3_OR_4HDLC	0x08000000
147 
148 /* default = no loopback */
149 #define CCR_LOOPBACK			0x02000000
150 
151 /* HSS number, default = 0 (first) */
152 #define CCR_SECOND_HSS			0x01000000
153 
154 
155 /* hss_config, clkCR: main:10, num:10, denom:12 */
156 #define CLK42X_SPEED_EXP	((0x3FF << 22) | (  2 << 12) |   15) /*65 KHz*/
157 
158 #define CLK42X_SPEED_512KHZ	((  130 << 22) | (  2 << 12) |   15)
159 #define CLK42X_SPEED_1536KHZ	((   43 << 22) | ( 18 << 12) |   47)
160 #define CLK42X_SPEED_1544KHZ	((   43 << 22) | ( 33 << 12) |  192)
161 #define CLK42X_SPEED_2048KHZ	((   32 << 22) | ( 34 << 12) |   63)
162 #define CLK42X_SPEED_4096KHZ	((   16 << 22) | ( 34 << 12) |  127)
163 #define CLK42X_SPEED_8192KHZ	((    8 << 22) | ( 34 << 12) |  255)
164 
165 #define CLK46X_SPEED_512KHZ	((  130 << 22) | ( 24 << 12) |  127)
166 #define CLK46X_SPEED_1536KHZ	((   43 << 22) | (152 << 12) |  383)
167 #define CLK46X_SPEED_1544KHZ	((   43 << 22) | ( 66 << 12) |  385)
168 #define CLK46X_SPEED_2048KHZ	((   32 << 22) | (280 << 12) |  511)
169 #define CLK46X_SPEED_4096KHZ	((   16 << 22) | (280 << 12) | 1023)
170 #define CLK46X_SPEED_8192KHZ	((    8 << 22) | (280 << 12) | 2047)
171 
172 /*
173  * HSS_CONFIG_CLOCK_CR register consists of 3 parts:
174  *     A (10 bits), B (10 bits) and C (12 bits).
175  * IXP42x HSS clock generator operation (verified with an oscilloscope):
176  * Each clock bit takes 7.5 ns (1 / 133.xx MHz).
177  * The clock sequence consists of (C - B) states of 0s and 1s, each state is
178  * A bits wide. It's followed by (B + 1) states of 0s and 1s, each state is
179  * (A + 1) bits wide.
180  *
181  * The resulting average clock frequency (assuming 33.333 MHz oscillator) is:
182  * freq = 66.666 MHz / (A + (B + 1) / (C + 1))
183  * minimum freq = 66.666 MHz / (A + 1)
184  * maximum freq = 66.666 MHz / A
185  *
186  * Example: A = 2, B = 2, C = 7, CLOCK_CR register = 2 << 22 | 2 << 12 | 7
187  * freq = 66.666 MHz / (2 + (2 + 1) / (7 + 1)) = 28.07 MHz (Mb/s).
188  * The clock sequence is: 1100110011 (5 doubles) 000111000 (3 triples).
189  * The sequence takes (C - B) * A + (B + 1) * (A + 1) = 5 * 2 + 3 * 3 bits
190  * = 19 bits (each 7.5 ns long) = 142.5 ns (then the sequence repeats).
191  * The sequence consists of 4 complete clock periods, thus the average
192  * frequency (= clock rate) is 4 / 142.5 ns = 28.07 MHz (Mb/s).
193  * (max specified clock rate for IXP42x HSS is 8.192 Mb/s).
194  */
195 
196 /* hss_config, LUT entries */
197 #define TDMMAP_UNASSIGNED	0
198 #define TDMMAP_HDLC		1	/* HDLC - packetized */
199 #define TDMMAP_VOICE56K		2	/* Voice56K - 7-bit channelized */
200 #define TDMMAP_VOICE64K		3	/* Voice64K - 8-bit channelized */
201 
202 /* offsets into HSS config */
203 #define HSS_CONFIG_TX_PCR	0x00 /* port configuration registers */
204 #define HSS_CONFIG_RX_PCR	0x04
205 #define HSS_CONFIG_CORE_CR	0x08 /* loopback control, HSS# */
206 #define HSS_CONFIG_CLOCK_CR	0x0C /* clock generator control */
207 #define HSS_CONFIG_TX_FCR	0x10 /* frame configuration registers */
208 #define HSS_CONFIG_RX_FCR	0x14
209 #define HSS_CONFIG_TX_LUT	0x18 /* channel look-up tables */
210 #define HSS_CONFIG_RX_LUT	0x38
211 
212 
213 /* NPE command codes */
214 /* writes the ConfigWord value to the location specified by offset */
215 #define PORT_CONFIG_WRITE		0x40
216 
217 /* triggers the NPE to load the contents of the configuration table */
218 #define PORT_CONFIG_LOAD		0x41
219 
220 /* triggers the NPE to return an HssErrorReadResponse message */
221 #define PORT_ERROR_READ			0x42
222 
223 /* triggers the NPE to reset internal status and enable the HssPacketized
224    operation for the flow specified by pPipe */
225 #define PKT_PIPE_FLOW_ENABLE		0x50
226 #define PKT_PIPE_FLOW_DISABLE		0x51
227 #define PKT_NUM_PIPES_WRITE		0x52
228 #define PKT_PIPE_FIFO_SIZEW_WRITE	0x53
229 #define PKT_PIPE_HDLC_CFG_WRITE		0x54
230 #define PKT_PIPE_IDLE_PATTERN_WRITE	0x55
231 #define PKT_PIPE_RX_SIZE_WRITE		0x56
232 #define PKT_PIPE_MODE_WRITE		0x57
233 
234 /* HDLC packet status values - desc->status */
235 #define ERR_SHUTDOWN		1 /* stop or shutdown occurrence */
236 #define ERR_HDLC_ALIGN		2 /* HDLC alignment error */
237 #define ERR_HDLC_FCS		3 /* HDLC Frame Check Sum error */
238 #define ERR_RXFREE_Q_EMPTY	4 /* RX-free queue became empty while receiving
239 				     this packet (if buf_len < pkt_len) */
240 #define ERR_HDLC_TOO_LONG	5 /* HDLC frame size too long */
241 #define ERR_HDLC_ABORT		6 /* abort sequence received */
242 #define ERR_DISCONNECTING	7 /* disconnect is in progress */
243 
244 
245 #ifdef __ARMEB__
246 typedef struct sk_buff buffer_t;
247 #define free_buffer dev_kfree_skb
248 #define free_buffer_irq dev_consume_skb_irq
249 #else
250 typedef void buffer_t;
251 #define free_buffer kfree
252 #define free_buffer_irq kfree
253 #endif
254 
255 struct port {
256 	struct device *dev;
257 	struct npe *npe;
258 	struct net_device *netdev;
259 	struct napi_struct napi;
260 	struct hss_plat_info *plat;
261 	buffer_t *rx_buff_tab[RX_DESCS], *tx_buff_tab[TX_DESCS];
262 	struct desc *desc_tab;	/* coherent */
263 	dma_addr_t desc_tab_phys;
264 	unsigned int id;
265 	unsigned int clock_type, clock_rate, loopback;
266 	unsigned int initialized, carrier;
267 	u8 hdlc_cfg;
268 	u32 clock_reg;
269 };
270 
271 /* NPE message structure */
272 struct msg {
273 #ifdef __ARMEB__
274 	u8 cmd, unused, hss_port, index;
275 	union {
276 		struct { u8 data8a, data8b, data8c, data8d; };
277 		struct { u16 data16a, data16b; };
278 		struct { u32 data32; };
279 	};
280 #else
281 	u8 index, hss_port, unused, cmd;
282 	union {
283 		struct { u8 data8d, data8c, data8b, data8a; };
284 		struct { u16 data16b, data16a; };
285 		struct { u32 data32; };
286 	};
287 #endif
288 };
289 
290 /* HDLC packet descriptor */
291 struct desc {
292 	u32 next;		/* pointer to next buffer, unused */
293 
294 #ifdef __ARMEB__
295 	u16 buf_len;		/* buffer length */
296 	u16 pkt_len;		/* packet length */
297 	u32 data;		/* pointer to data buffer in RAM */
298 	u8 status;
299 	u8 error_count;
300 	u16 __reserved;
301 #else
302 	u16 pkt_len;		/* packet length */
303 	u16 buf_len;		/* buffer length */
304 	u32 data;		/* pointer to data buffer in RAM */
305 	u16 __reserved;
306 	u8 error_count;
307 	u8 status;
308 #endif
309 	u32 __reserved1[4];
310 };
311 
312 
313 #define rx_desc_phys(port, n)	((port)->desc_tab_phys +		\
314 				 (n) * sizeof(struct desc))
315 #define rx_desc_ptr(port, n)	(&(port)->desc_tab[n])
316 
317 #define tx_desc_phys(port, n)	((port)->desc_tab_phys +		\
318 				 ((n) + RX_DESCS) * sizeof(struct desc))
319 #define tx_desc_ptr(port, n)	(&(port)->desc_tab[(n) + RX_DESCS])
320 
321 /*****************************************************************************
322  * global variables
323  ****************************************************************************/
324 
325 static int ports_open;
326 static struct dma_pool *dma_pool;
327 static DEFINE_SPINLOCK(npe_lock);
328 
329 static const struct {
330 	int tx, txdone, rx, rxfree;
331 }queue_ids[2] = {{HSS0_PKT_TX0_QUEUE, HSS0_PKT_TXDONE_QUEUE, HSS0_PKT_RX_QUEUE,
332 		  HSS0_PKT_RXFREE0_QUEUE},
333 		 {HSS1_PKT_TX0_QUEUE, HSS1_PKT_TXDONE_QUEUE, HSS1_PKT_RX_QUEUE,
334 		  HSS1_PKT_RXFREE0_QUEUE},
335 };
336 
337 /*****************************************************************************
338  * utility functions
339  ****************************************************************************/
340 
341 static inline struct port* dev_to_port(struct net_device *dev)
342 {
343 	return dev_to_hdlc(dev)->priv;
344 }
345 
346 #ifndef __ARMEB__
347 static inline void memcpy_swab32(u32 *dest, u32 *src, int cnt)
348 {
349 	int i;
350 	for (i = 0; i < cnt; i++)
351 		dest[i] = swab32(src[i]);
352 }
353 #endif
354 
355 /*****************************************************************************
356  * HSS access
357  ****************************************************************************/
358 
359 static void hss_npe_send(struct port *port, struct msg *msg, const char* what)
360 {
361 	u32 *val = (u32*)msg;
362 	if (npe_send_message(port->npe, msg, what)) {
363 		pr_crit("HSS-%i: unable to send command [%08X:%08X] to %s\n",
364 			port->id, val[0], val[1], npe_name(port->npe));
365 		BUG();
366 	}
367 }
368 
369 static void hss_config_set_lut(struct port *port)
370 {
371 	struct msg msg;
372 	int ch;
373 
374 	memset(&msg, 0, sizeof(msg));
375 	msg.cmd = PORT_CONFIG_WRITE;
376 	msg.hss_port = port->id;
377 
378 	for (ch = 0; ch < MAX_CHANNELS; ch++) {
379 		msg.data32 >>= 2;
380 		msg.data32 |= TDMMAP_HDLC << 30;
381 
382 		if (ch % 16 == 15) {
383 			msg.index = HSS_CONFIG_TX_LUT + ((ch / 4) & ~3);
384 			hss_npe_send(port, &msg, "HSS_SET_TX_LUT");
385 
386 			msg.index += HSS_CONFIG_RX_LUT - HSS_CONFIG_TX_LUT;
387 			hss_npe_send(port, &msg, "HSS_SET_RX_LUT");
388 		}
389 	}
390 }
391 
392 static void hss_config(struct port *port)
393 {
394 	struct msg msg;
395 
396 	memset(&msg, 0, sizeof(msg));
397 	msg.cmd = PORT_CONFIG_WRITE;
398 	msg.hss_port = port->id;
399 	msg.index = HSS_CONFIG_TX_PCR;
400 	msg.data32 = PCR_FRM_PULSE_DISABLED | PCR_MSB_ENDIAN |
401 		PCR_TX_DATA_ENABLE | PCR_SOF_NO_FBIT;
402 	if (port->clock_type == CLOCK_INT)
403 		msg.data32 |= PCR_SYNC_CLK_DIR_OUTPUT;
404 	hss_npe_send(port, &msg, "HSS_SET_TX_PCR");
405 
406 	msg.index = HSS_CONFIG_RX_PCR;
407 	msg.data32 ^= PCR_TX_DATA_ENABLE | PCR_DCLK_EDGE_RISING;
408 	hss_npe_send(port, &msg, "HSS_SET_RX_PCR");
409 
410 	memset(&msg, 0, sizeof(msg));
411 	msg.cmd = PORT_CONFIG_WRITE;
412 	msg.hss_port = port->id;
413 	msg.index = HSS_CONFIG_CORE_CR;
414 	msg.data32 = (port->loopback ? CCR_LOOPBACK : 0) |
415 		(port->id ? CCR_SECOND_HSS : 0);
416 	hss_npe_send(port, &msg, "HSS_SET_CORE_CR");
417 
418 	memset(&msg, 0, sizeof(msg));
419 	msg.cmd = PORT_CONFIG_WRITE;
420 	msg.hss_port = port->id;
421 	msg.index = HSS_CONFIG_CLOCK_CR;
422 	msg.data32 = port->clock_reg;
423 	hss_npe_send(port, &msg, "HSS_SET_CLOCK_CR");
424 
425 	memset(&msg, 0, sizeof(msg));
426 	msg.cmd = PORT_CONFIG_WRITE;
427 	msg.hss_port = port->id;
428 	msg.index = HSS_CONFIG_TX_FCR;
429 	msg.data16a = FRAME_OFFSET;
430 	msg.data16b = FRAME_SIZE - 1;
431 	hss_npe_send(port, &msg, "HSS_SET_TX_FCR");
432 
433 	memset(&msg, 0, sizeof(msg));
434 	msg.cmd = PORT_CONFIG_WRITE;
435 	msg.hss_port = port->id;
436 	msg.index = HSS_CONFIG_RX_FCR;
437 	msg.data16a = FRAME_OFFSET;
438 	msg.data16b = FRAME_SIZE - 1;
439 	hss_npe_send(port, &msg, "HSS_SET_RX_FCR");
440 
441 	hss_config_set_lut(port);
442 
443 	memset(&msg, 0, sizeof(msg));
444 	msg.cmd = PORT_CONFIG_LOAD;
445 	msg.hss_port = port->id;
446 	hss_npe_send(port, &msg, "HSS_LOAD_CONFIG");
447 
448 	if (npe_recv_message(port->npe, &msg, "HSS_LOAD_CONFIG") ||
449 	    /* HSS_LOAD_CONFIG for port #1 returns port_id = #4 */
450 	    msg.cmd != PORT_CONFIG_LOAD || msg.data32) {
451 		pr_crit("HSS-%i: HSS_LOAD_CONFIG failed\n", port->id);
452 		BUG();
453 	}
454 
455 	/* HDLC may stop working without this - check FIXME */
456 	npe_recv_message(port->npe, &msg, "FLUSH_IT");
457 }
458 
459 static void hss_set_hdlc_cfg(struct port *port)
460 {
461 	struct msg msg;
462 
463 	memset(&msg, 0, sizeof(msg));
464 	msg.cmd = PKT_PIPE_HDLC_CFG_WRITE;
465 	msg.hss_port = port->id;
466 	msg.data8a = port->hdlc_cfg; /* rx_cfg */
467 	msg.data8b = port->hdlc_cfg | (PKT_EXTRA_FLAGS << 3); /* tx_cfg */
468 	hss_npe_send(port, &msg, "HSS_SET_HDLC_CFG");
469 }
470 
471 static u32 hss_get_status(struct port *port)
472 {
473 	struct msg msg;
474 
475 	memset(&msg, 0, sizeof(msg));
476 	msg.cmd = PORT_ERROR_READ;
477 	msg.hss_port = port->id;
478 	hss_npe_send(port, &msg, "PORT_ERROR_READ");
479 	if (npe_recv_message(port->npe, &msg, "PORT_ERROR_READ")) {
480 		pr_crit("HSS-%i: unable to read HSS status\n", port->id);
481 		BUG();
482 	}
483 
484 	return msg.data32;
485 }
486 
487 static void hss_start_hdlc(struct port *port)
488 {
489 	struct msg msg;
490 
491 	memset(&msg, 0, sizeof(msg));
492 	msg.cmd = PKT_PIPE_FLOW_ENABLE;
493 	msg.hss_port = port->id;
494 	msg.data32 = 0;
495 	hss_npe_send(port, &msg, "HSS_ENABLE_PKT_PIPE");
496 }
497 
498 static void hss_stop_hdlc(struct port *port)
499 {
500 	struct msg msg;
501 
502 	memset(&msg, 0, sizeof(msg));
503 	msg.cmd = PKT_PIPE_FLOW_DISABLE;
504 	msg.hss_port = port->id;
505 	hss_npe_send(port, &msg, "HSS_DISABLE_PKT_PIPE");
506 	hss_get_status(port); /* make sure it's halted */
507 }
508 
509 static int hss_load_firmware(struct port *port)
510 {
511 	struct msg msg;
512 	int err;
513 
514 	if (port->initialized)
515 		return 0;
516 
517 	if (!npe_running(port->npe) &&
518 	    (err = npe_load_firmware(port->npe, npe_name(port->npe),
519 				     port->dev)))
520 		return err;
521 
522 	/* HDLC mode configuration */
523 	memset(&msg, 0, sizeof(msg));
524 	msg.cmd = PKT_NUM_PIPES_WRITE;
525 	msg.hss_port = port->id;
526 	msg.data8a = PKT_NUM_PIPES;
527 	hss_npe_send(port, &msg, "HSS_SET_PKT_PIPES");
528 
529 	msg.cmd = PKT_PIPE_FIFO_SIZEW_WRITE;
530 	msg.data8a = PKT_PIPE_FIFO_SIZEW;
531 	hss_npe_send(port, &msg, "HSS_SET_PKT_FIFO");
532 
533 	msg.cmd = PKT_PIPE_MODE_WRITE;
534 	msg.data8a = NPE_PKT_MODE_HDLC;
535 	/* msg.data8b = inv_mask */
536 	/* msg.data8c = or_mask */
537 	hss_npe_send(port, &msg, "HSS_SET_PKT_MODE");
538 
539 	msg.cmd = PKT_PIPE_RX_SIZE_WRITE;
540 	msg.data16a = HDLC_MAX_MRU; /* including CRC */
541 	hss_npe_send(port, &msg, "HSS_SET_PKT_RX_SIZE");
542 
543 	msg.cmd = PKT_PIPE_IDLE_PATTERN_WRITE;
544 	msg.data32 = 0x7F7F7F7F; /* ??? FIXME */
545 	hss_npe_send(port, &msg, "HSS_SET_PKT_IDLE");
546 
547 	port->initialized = 1;
548 	return 0;
549 }
550 
551 /*****************************************************************************
552  * packetized (HDLC) operation
553  ****************************************************************************/
554 
555 static inline void debug_pkt(struct net_device *dev, const char *func,
556 			     u8 *data, int len)
557 {
558 #if DEBUG_PKT_BYTES
559 	int i;
560 
561 	printk(KERN_DEBUG "%s: %s(%i)", dev->name, func, len);
562 	for (i = 0; i < len; i++) {
563 		if (i >= DEBUG_PKT_BYTES)
564 			break;
565 		printk("%s%02X", !(i % 4) ? " " : "", data[i]);
566 	}
567 	printk("\n");
568 #endif
569 }
570 
571 
572 static inline void debug_desc(u32 phys, struct desc *desc)
573 {
574 #if DEBUG_DESC
575 	printk(KERN_DEBUG "%X: %X %3X %3X %08X %X %X\n",
576 	       phys, desc->next, desc->buf_len, desc->pkt_len,
577 	       desc->data, desc->status, desc->error_count);
578 #endif
579 }
580 
581 static inline int queue_get_desc(unsigned int queue, struct port *port,
582 				 int is_tx)
583 {
584 	u32 phys, tab_phys, n_desc;
585 	struct desc *tab;
586 
587 	if (!(phys = qmgr_get_entry(queue)))
588 		return -1;
589 
590 	BUG_ON(phys & 0x1F);
591 	tab_phys = is_tx ? tx_desc_phys(port, 0) : rx_desc_phys(port, 0);
592 	tab = is_tx ? tx_desc_ptr(port, 0) : rx_desc_ptr(port, 0);
593 	n_desc = (phys - tab_phys) / sizeof(struct desc);
594 	BUG_ON(n_desc >= (is_tx ? TX_DESCS : RX_DESCS));
595 	debug_desc(phys, &tab[n_desc]);
596 	BUG_ON(tab[n_desc].next);
597 	return n_desc;
598 }
599 
600 static inline void queue_put_desc(unsigned int queue, u32 phys,
601 				  struct desc *desc)
602 {
603 	debug_desc(phys, desc);
604 	BUG_ON(phys & 0x1F);
605 	qmgr_put_entry(queue, phys);
606 	/* Don't check for queue overflow here, we've allocated sufficient
607 	   length and queues >= 32 don't support this check anyway. */
608 }
609 
610 
611 static inline void dma_unmap_tx(struct port *port, struct desc *desc)
612 {
613 #ifdef __ARMEB__
614 	dma_unmap_single(&port->netdev->dev, desc->data,
615 			 desc->buf_len, DMA_TO_DEVICE);
616 #else
617 	dma_unmap_single(&port->netdev->dev, desc->data & ~3,
618 			 ALIGN((desc->data & 3) + desc->buf_len, 4),
619 			 DMA_TO_DEVICE);
620 #endif
621 }
622 
623 
624 static void hss_hdlc_set_carrier(void *pdev, int carrier)
625 {
626 	struct net_device *netdev = pdev;
627 	struct port *port = dev_to_port(netdev);
628 	unsigned long flags;
629 
630 	spin_lock_irqsave(&npe_lock, flags);
631 	port->carrier = carrier;
632 	if (!port->loopback) {
633 		if (carrier)
634 			netif_carrier_on(netdev);
635 		else
636 			netif_carrier_off(netdev);
637 	}
638 	spin_unlock_irqrestore(&npe_lock, flags);
639 }
640 
641 static void hss_hdlc_rx_irq(void *pdev)
642 {
643 	struct net_device *dev = pdev;
644 	struct port *port = dev_to_port(dev);
645 
646 #if DEBUG_RX
647 	printk(KERN_DEBUG "%s: hss_hdlc_rx_irq\n", dev->name);
648 #endif
649 	qmgr_disable_irq(queue_ids[port->id].rx);
650 	napi_schedule(&port->napi);
651 }
652 
653 static int hss_hdlc_poll(struct napi_struct *napi, int budget)
654 {
655 	struct port *port = container_of(napi, struct port, napi);
656 	struct net_device *dev = port->netdev;
657 	unsigned int rxq = queue_ids[port->id].rx;
658 	unsigned int rxfreeq = queue_ids[port->id].rxfree;
659 	int received = 0;
660 
661 #if DEBUG_RX
662 	printk(KERN_DEBUG "%s: hss_hdlc_poll\n", dev->name);
663 #endif
664 
665 	while (received < budget) {
666 		struct sk_buff *skb;
667 		struct desc *desc;
668 		int n;
669 #ifdef __ARMEB__
670 		struct sk_buff *temp;
671 		u32 phys;
672 #endif
673 
674 		if ((n = queue_get_desc(rxq, port, 0)) < 0) {
675 #if DEBUG_RX
676 			printk(KERN_DEBUG "%s: hss_hdlc_poll"
677 			       " napi_complete\n", dev->name);
678 #endif
679 			napi_complete(napi);
680 			qmgr_enable_irq(rxq);
681 			if (!qmgr_stat_empty(rxq) &&
682 			    napi_reschedule(napi)) {
683 #if DEBUG_RX
684 				printk(KERN_DEBUG "%s: hss_hdlc_poll"
685 				       " napi_reschedule succeeded\n",
686 				       dev->name);
687 #endif
688 				qmgr_disable_irq(rxq);
689 				continue;
690 			}
691 #if DEBUG_RX
692 			printk(KERN_DEBUG "%s: hss_hdlc_poll all done\n",
693 			       dev->name);
694 #endif
695 			return received; /* all work done */
696 		}
697 
698 		desc = rx_desc_ptr(port, n);
699 #if 0 /* FIXME - error_count counts modulo 256, perhaps we should use it */
700 		if (desc->error_count)
701 			printk(KERN_DEBUG "%s: hss_hdlc_poll status 0x%02X"
702 			       " errors %u\n", dev->name, desc->status,
703 			       desc->error_count);
704 #endif
705 		skb = NULL;
706 		switch (desc->status) {
707 		case 0:
708 #ifdef __ARMEB__
709 			if ((skb = netdev_alloc_skb(dev, RX_SIZE)) != NULL) {
710 				phys = dma_map_single(&dev->dev, skb->data,
711 						      RX_SIZE,
712 						      DMA_FROM_DEVICE);
713 				if (dma_mapping_error(&dev->dev, phys)) {
714 					dev_kfree_skb(skb);
715 					skb = NULL;
716 				}
717 			}
718 #else
719 			skb = netdev_alloc_skb(dev, desc->pkt_len);
720 #endif
721 			if (!skb)
722 				dev->stats.rx_dropped++;
723 			break;
724 		case ERR_HDLC_ALIGN:
725 		case ERR_HDLC_ABORT:
726 			dev->stats.rx_frame_errors++;
727 			dev->stats.rx_errors++;
728 			break;
729 		case ERR_HDLC_FCS:
730 			dev->stats.rx_crc_errors++;
731 			dev->stats.rx_errors++;
732 			break;
733 		case ERR_HDLC_TOO_LONG:
734 			dev->stats.rx_length_errors++;
735 			dev->stats.rx_errors++;
736 			break;
737 		default:	/* FIXME - remove printk */
738 			netdev_err(dev, "hss_hdlc_poll: status 0x%02X errors %u\n",
739 				   desc->status, desc->error_count);
740 			dev->stats.rx_errors++;
741 		}
742 
743 		if (!skb) {
744 			/* put the desc back on RX-ready queue */
745 			desc->buf_len = RX_SIZE;
746 			desc->pkt_len = desc->status = 0;
747 			queue_put_desc(rxfreeq, rx_desc_phys(port, n), desc);
748 			continue;
749 		}
750 
751 		/* process received frame */
752 #ifdef __ARMEB__
753 		temp = skb;
754 		skb = port->rx_buff_tab[n];
755 		dma_unmap_single(&dev->dev, desc->data,
756 				 RX_SIZE, DMA_FROM_DEVICE);
757 #else
758 		dma_sync_single_for_cpu(&dev->dev, desc->data,
759 					RX_SIZE, DMA_FROM_DEVICE);
760 		memcpy_swab32((u32 *)skb->data, (u32 *)port->rx_buff_tab[n],
761 			      ALIGN(desc->pkt_len, 4) / 4);
762 #endif
763 		skb_put(skb, desc->pkt_len);
764 
765 		debug_pkt(dev, "hss_hdlc_poll", skb->data, skb->len);
766 
767 		skb->protocol = hdlc_type_trans(skb, dev);
768 		dev->stats.rx_packets++;
769 		dev->stats.rx_bytes += skb->len;
770 		netif_receive_skb(skb);
771 
772 		/* put the new buffer on RX-free queue */
773 #ifdef __ARMEB__
774 		port->rx_buff_tab[n] = temp;
775 		desc->data = phys;
776 #endif
777 		desc->buf_len = RX_SIZE;
778 		desc->pkt_len = 0;
779 		queue_put_desc(rxfreeq, rx_desc_phys(port, n), desc);
780 		received++;
781 	}
782 #if DEBUG_RX
783 	printk(KERN_DEBUG "hss_hdlc_poll: end, not all work done\n");
784 #endif
785 	return received;	/* not all work done */
786 }
787 
788 
789 static void hss_hdlc_txdone_irq(void *pdev)
790 {
791 	struct net_device *dev = pdev;
792 	struct port *port = dev_to_port(dev);
793 	int n_desc;
794 
795 #if DEBUG_TX
796 	printk(KERN_DEBUG DRV_NAME ": hss_hdlc_txdone_irq\n");
797 #endif
798 	while ((n_desc = queue_get_desc(queue_ids[port->id].txdone,
799 					port, 1)) >= 0) {
800 		struct desc *desc;
801 		int start;
802 
803 		desc = tx_desc_ptr(port, n_desc);
804 
805 		dev->stats.tx_packets++;
806 		dev->stats.tx_bytes += desc->pkt_len;
807 
808 		dma_unmap_tx(port, desc);
809 #if DEBUG_TX
810 		printk(KERN_DEBUG "%s: hss_hdlc_txdone_irq free %p\n",
811 		       dev->name, port->tx_buff_tab[n_desc]);
812 #endif
813 		free_buffer_irq(port->tx_buff_tab[n_desc]);
814 		port->tx_buff_tab[n_desc] = NULL;
815 
816 		start = qmgr_stat_below_low_watermark(port->plat->txreadyq);
817 		queue_put_desc(port->plat->txreadyq,
818 			       tx_desc_phys(port, n_desc), desc);
819 		if (start) { /* TX-ready queue was empty */
820 #if DEBUG_TX
821 			printk(KERN_DEBUG "%s: hss_hdlc_txdone_irq xmit"
822 			       " ready\n", dev->name);
823 #endif
824 			netif_wake_queue(dev);
825 		}
826 	}
827 }
828 
829 static int hss_hdlc_xmit(struct sk_buff *skb, struct net_device *dev)
830 {
831 	struct port *port = dev_to_port(dev);
832 	unsigned int txreadyq = port->plat->txreadyq;
833 	int len, offset, bytes, n;
834 	void *mem;
835 	u32 phys;
836 	struct desc *desc;
837 
838 #if DEBUG_TX
839 	printk(KERN_DEBUG "%s: hss_hdlc_xmit\n", dev->name);
840 #endif
841 
842 	if (unlikely(skb->len > HDLC_MAX_MRU)) {
843 		dev_kfree_skb(skb);
844 		dev->stats.tx_errors++;
845 		return NETDEV_TX_OK;
846 	}
847 
848 	debug_pkt(dev, "hss_hdlc_xmit", skb->data, skb->len);
849 
850 	len = skb->len;
851 #ifdef __ARMEB__
852 	offset = 0; /* no need to keep alignment */
853 	bytes = len;
854 	mem = skb->data;
855 #else
856 	offset = (int)skb->data & 3; /* keep 32-bit alignment */
857 	bytes = ALIGN(offset + len, 4);
858 	if (!(mem = kmalloc(bytes, GFP_ATOMIC))) {
859 		dev_kfree_skb(skb);
860 		dev->stats.tx_dropped++;
861 		return NETDEV_TX_OK;
862 	}
863 	memcpy_swab32(mem, (u32 *)((uintptr_t)skb->data & ~3), bytes / 4);
864 	dev_kfree_skb(skb);
865 #endif
866 
867 	phys = dma_map_single(&dev->dev, mem, bytes, DMA_TO_DEVICE);
868 	if (dma_mapping_error(&dev->dev, phys)) {
869 #ifdef __ARMEB__
870 		dev_kfree_skb(skb);
871 #else
872 		kfree(mem);
873 #endif
874 		dev->stats.tx_dropped++;
875 		return NETDEV_TX_OK;
876 	}
877 
878 	n = queue_get_desc(txreadyq, port, 1);
879 	BUG_ON(n < 0);
880 	desc = tx_desc_ptr(port, n);
881 
882 #ifdef __ARMEB__
883 	port->tx_buff_tab[n] = skb;
884 #else
885 	port->tx_buff_tab[n] = mem;
886 #endif
887 	desc->data = phys + offset;
888 	desc->buf_len = desc->pkt_len = len;
889 
890 	wmb();
891 	queue_put_desc(queue_ids[port->id].tx, tx_desc_phys(port, n), desc);
892 
893 	if (qmgr_stat_below_low_watermark(txreadyq)) { /* empty */
894 #if DEBUG_TX
895 		printk(KERN_DEBUG "%s: hss_hdlc_xmit queue full\n", dev->name);
896 #endif
897 		netif_stop_queue(dev);
898 		/* we could miss TX ready interrupt */
899 		if (!qmgr_stat_below_low_watermark(txreadyq)) {
900 #if DEBUG_TX
901 			printk(KERN_DEBUG "%s: hss_hdlc_xmit ready again\n",
902 			       dev->name);
903 #endif
904 			netif_wake_queue(dev);
905 		}
906 	}
907 
908 #if DEBUG_TX
909 	printk(KERN_DEBUG "%s: hss_hdlc_xmit end\n", dev->name);
910 #endif
911 	return NETDEV_TX_OK;
912 }
913 
914 
915 static int request_hdlc_queues(struct port *port)
916 {
917 	int err;
918 
919 	err = qmgr_request_queue(queue_ids[port->id].rxfree, RX_DESCS, 0, 0,
920 				 "%s:RX-free", port->netdev->name);
921 	if (err)
922 		return err;
923 
924 	err = qmgr_request_queue(queue_ids[port->id].rx, RX_DESCS, 0, 0,
925 				 "%s:RX", port->netdev->name);
926 	if (err)
927 		goto rel_rxfree;
928 
929 	err = qmgr_request_queue(queue_ids[port->id].tx, TX_DESCS, 0, 0,
930 				 "%s:TX", port->netdev->name);
931 	if (err)
932 		goto rel_rx;
933 
934 	err = qmgr_request_queue(port->plat->txreadyq, TX_DESCS, 0, 0,
935 				 "%s:TX-ready", port->netdev->name);
936 	if (err)
937 		goto rel_tx;
938 
939 	err = qmgr_request_queue(queue_ids[port->id].txdone, TX_DESCS, 0, 0,
940 				 "%s:TX-done", port->netdev->name);
941 	if (err)
942 		goto rel_txready;
943 	return 0;
944 
945 rel_txready:
946 	qmgr_release_queue(port->plat->txreadyq);
947 rel_tx:
948 	qmgr_release_queue(queue_ids[port->id].tx);
949 rel_rx:
950 	qmgr_release_queue(queue_ids[port->id].rx);
951 rel_rxfree:
952 	qmgr_release_queue(queue_ids[port->id].rxfree);
953 	printk(KERN_DEBUG "%s: unable to request hardware queues\n",
954 	       port->netdev->name);
955 	return err;
956 }
957 
958 static void release_hdlc_queues(struct port *port)
959 {
960 	qmgr_release_queue(queue_ids[port->id].rxfree);
961 	qmgr_release_queue(queue_ids[port->id].rx);
962 	qmgr_release_queue(queue_ids[port->id].txdone);
963 	qmgr_release_queue(queue_ids[port->id].tx);
964 	qmgr_release_queue(port->plat->txreadyq);
965 }
966 
967 static int init_hdlc_queues(struct port *port)
968 {
969 	int i;
970 
971 	if (!ports_open) {
972 		dma_pool = dma_pool_create(DRV_NAME, &port->netdev->dev,
973 					   POOL_ALLOC_SIZE, 32, 0);
974 		if (!dma_pool)
975 			return -ENOMEM;
976 	}
977 
978 	if (!(port->desc_tab = dma_pool_alloc(dma_pool, GFP_KERNEL,
979 					      &port->desc_tab_phys)))
980 		return -ENOMEM;
981 	memset(port->desc_tab, 0, POOL_ALLOC_SIZE);
982 	memset(port->rx_buff_tab, 0, sizeof(port->rx_buff_tab)); /* tables */
983 	memset(port->tx_buff_tab, 0, sizeof(port->tx_buff_tab));
984 
985 	/* Setup RX buffers */
986 	for (i = 0; i < RX_DESCS; i++) {
987 		struct desc *desc = rx_desc_ptr(port, i);
988 		buffer_t *buff;
989 		void *data;
990 #ifdef __ARMEB__
991 		if (!(buff = netdev_alloc_skb(port->netdev, RX_SIZE)))
992 			return -ENOMEM;
993 		data = buff->data;
994 #else
995 		if (!(buff = kmalloc(RX_SIZE, GFP_KERNEL)))
996 			return -ENOMEM;
997 		data = buff;
998 #endif
999 		desc->buf_len = RX_SIZE;
1000 		desc->data = dma_map_single(&port->netdev->dev, data,
1001 					    RX_SIZE, DMA_FROM_DEVICE);
1002 		if (dma_mapping_error(&port->netdev->dev, desc->data)) {
1003 			free_buffer(buff);
1004 			return -EIO;
1005 		}
1006 		port->rx_buff_tab[i] = buff;
1007 	}
1008 
1009 	return 0;
1010 }
1011 
1012 static void destroy_hdlc_queues(struct port *port)
1013 {
1014 	int i;
1015 
1016 	if (port->desc_tab) {
1017 		for (i = 0; i < RX_DESCS; i++) {
1018 			struct desc *desc = rx_desc_ptr(port, i);
1019 			buffer_t *buff = port->rx_buff_tab[i];
1020 			if (buff) {
1021 				dma_unmap_single(&port->netdev->dev,
1022 						 desc->data, RX_SIZE,
1023 						 DMA_FROM_DEVICE);
1024 				free_buffer(buff);
1025 			}
1026 		}
1027 		for (i = 0; i < TX_DESCS; i++) {
1028 			struct desc *desc = tx_desc_ptr(port, i);
1029 			buffer_t *buff = port->tx_buff_tab[i];
1030 			if (buff) {
1031 				dma_unmap_tx(port, desc);
1032 				free_buffer(buff);
1033 			}
1034 		}
1035 		dma_pool_free(dma_pool, port->desc_tab, port->desc_tab_phys);
1036 		port->desc_tab = NULL;
1037 	}
1038 
1039 	if (!ports_open && dma_pool) {
1040 		dma_pool_destroy(dma_pool);
1041 		dma_pool = NULL;
1042 	}
1043 }
1044 
1045 static int hss_hdlc_open(struct net_device *dev)
1046 {
1047 	struct port *port = dev_to_port(dev);
1048 	unsigned long flags;
1049 	int i, err = 0;
1050 
1051 	if ((err = hdlc_open(dev)))
1052 		return err;
1053 
1054 	if ((err = hss_load_firmware(port)))
1055 		goto err_hdlc_close;
1056 
1057 	if ((err = request_hdlc_queues(port)))
1058 		goto err_hdlc_close;
1059 
1060 	if ((err = init_hdlc_queues(port)))
1061 		goto err_destroy_queues;
1062 
1063 	spin_lock_irqsave(&npe_lock, flags);
1064 	if (port->plat->open)
1065 		if ((err = port->plat->open(port->id, dev,
1066 					    hss_hdlc_set_carrier)))
1067 			goto err_unlock;
1068 	spin_unlock_irqrestore(&npe_lock, flags);
1069 
1070 	/* Populate queues with buffers, no failure after this point */
1071 	for (i = 0; i < TX_DESCS; i++)
1072 		queue_put_desc(port->plat->txreadyq,
1073 			       tx_desc_phys(port, i), tx_desc_ptr(port, i));
1074 
1075 	for (i = 0; i < RX_DESCS; i++)
1076 		queue_put_desc(queue_ids[port->id].rxfree,
1077 			       rx_desc_phys(port, i), rx_desc_ptr(port, i));
1078 
1079 	napi_enable(&port->napi);
1080 	netif_start_queue(dev);
1081 
1082 	qmgr_set_irq(queue_ids[port->id].rx, QUEUE_IRQ_SRC_NOT_EMPTY,
1083 		     hss_hdlc_rx_irq, dev);
1084 
1085 	qmgr_set_irq(queue_ids[port->id].txdone, QUEUE_IRQ_SRC_NOT_EMPTY,
1086 		     hss_hdlc_txdone_irq, dev);
1087 	qmgr_enable_irq(queue_ids[port->id].txdone);
1088 
1089 	ports_open++;
1090 
1091 	hss_set_hdlc_cfg(port);
1092 	hss_config(port);
1093 
1094 	hss_start_hdlc(port);
1095 
1096 	/* we may already have RX data, enables IRQ */
1097 	napi_schedule(&port->napi);
1098 	return 0;
1099 
1100 err_unlock:
1101 	spin_unlock_irqrestore(&npe_lock, flags);
1102 err_destroy_queues:
1103 	destroy_hdlc_queues(port);
1104 	release_hdlc_queues(port);
1105 err_hdlc_close:
1106 	hdlc_close(dev);
1107 	return err;
1108 }
1109 
1110 static int hss_hdlc_close(struct net_device *dev)
1111 {
1112 	struct port *port = dev_to_port(dev);
1113 	unsigned long flags;
1114 	int i, buffs = RX_DESCS; /* allocated RX buffers */
1115 
1116 	spin_lock_irqsave(&npe_lock, flags);
1117 	ports_open--;
1118 	qmgr_disable_irq(queue_ids[port->id].rx);
1119 	netif_stop_queue(dev);
1120 	napi_disable(&port->napi);
1121 
1122 	hss_stop_hdlc(port);
1123 
1124 	while (queue_get_desc(queue_ids[port->id].rxfree, port, 0) >= 0)
1125 		buffs--;
1126 	while (queue_get_desc(queue_ids[port->id].rx, port, 0) >= 0)
1127 		buffs--;
1128 
1129 	if (buffs)
1130 		netdev_crit(dev, "unable to drain RX queue, %i buffer(s) left in NPE\n",
1131 			    buffs);
1132 
1133 	buffs = TX_DESCS;
1134 	while (queue_get_desc(queue_ids[port->id].tx, port, 1) >= 0)
1135 		buffs--; /* cancel TX */
1136 
1137 	i = 0;
1138 	do {
1139 		while (queue_get_desc(port->plat->txreadyq, port, 1) >= 0)
1140 			buffs--;
1141 		if (!buffs)
1142 			break;
1143 	} while (++i < MAX_CLOSE_WAIT);
1144 
1145 	if (buffs)
1146 		netdev_crit(dev, "unable to drain TX queue, %i buffer(s) left in NPE\n",
1147 			    buffs);
1148 #if DEBUG_CLOSE
1149 	if (!buffs)
1150 		printk(KERN_DEBUG "Draining TX queues took %i cycles\n", i);
1151 #endif
1152 	qmgr_disable_irq(queue_ids[port->id].txdone);
1153 
1154 	if (port->plat->close)
1155 		port->plat->close(port->id, dev);
1156 	spin_unlock_irqrestore(&npe_lock, flags);
1157 
1158 	destroy_hdlc_queues(port);
1159 	release_hdlc_queues(port);
1160 	hdlc_close(dev);
1161 	return 0;
1162 }
1163 
1164 
1165 static int hss_hdlc_attach(struct net_device *dev, unsigned short encoding,
1166 			   unsigned short parity)
1167 {
1168 	struct port *port = dev_to_port(dev);
1169 
1170 	if (encoding != ENCODING_NRZ)
1171 		return -EINVAL;
1172 
1173 	switch(parity) {
1174 	case PARITY_CRC16_PR1_CCITT:
1175 		port->hdlc_cfg = 0;
1176 		return 0;
1177 
1178 	case PARITY_CRC32_PR1_CCITT:
1179 		port->hdlc_cfg = PKT_HDLC_CRC_32;
1180 		return 0;
1181 
1182 	default:
1183 		return -EINVAL;
1184 	}
1185 }
1186 
1187 static u32 check_clock(u32 timer_freq, u32 rate, u32 a, u32 b, u32 c,
1188 		       u32 *best, u32 *best_diff, u32 *reg)
1189 {
1190 	/* a is 10-bit, b is 10-bit, c is 12-bit */
1191 	u64 new_rate;
1192 	u32 new_diff;
1193 
1194 	new_rate = timer_freq * (u64)(c + 1);
1195 	do_div(new_rate, a * (c + 1) + b + 1);
1196 	new_diff = abs((u32)new_rate - rate);
1197 
1198 	if (new_diff < *best_diff) {
1199 		*best = new_rate;
1200 		*best_diff = new_diff;
1201 		*reg = (a << 22) | (b << 12) | c;
1202 	}
1203 	return new_diff;
1204 }
1205 
1206 static void find_best_clock(u32 timer_freq, u32 rate, u32 *best, u32 *reg)
1207 {
1208 	u32 a, b, diff = 0xFFFFFFFF;
1209 
1210 	a = timer_freq / rate;
1211 
1212 	if (a > 0x3FF) { /* 10-bit value - we can go as slow as ca. 65 kb/s */
1213 		check_clock(timer_freq, rate, 0x3FF, 1, 1, best, &diff, reg);
1214 		return;
1215 	}
1216 	if (a == 0) { /* > 66.666 MHz */
1217 		a = 1; /* minimum divider is 1 (a = 0, b = 1, c = 1) */
1218 		rate = timer_freq;
1219 	}
1220 
1221 	if (rate * a == timer_freq) { /* don't divide by 0 later */
1222 		check_clock(timer_freq, rate, a - 1, 1, 1, best, &diff, reg);
1223 		return;
1224 	}
1225 
1226 	for (b = 0; b < 0x400; b++) {
1227 		u64 c = (b + 1) * (u64)rate;
1228 		do_div(c, timer_freq - rate * a);
1229 		c--;
1230 		if (c >= 0xFFF) { /* 12-bit - no need to check more 'b's */
1231 			if (b == 0 && /* also try a bit higher rate */
1232 			    !check_clock(timer_freq, rate, a - 1, 1, 1, best,
1233 					 &diff, reg))
1234 				return;
1235 			check_clock(timer_freq, rate, a, b, 0xFFF, best,
1236 				    &diff, reg);
1237 			return;
1238 		}
1239 		if (!check_clock(timer_freq, rate, a, b, c, best, &diff, reg))
1240 			return;
1241 		if (!check_clock(timer_freq, rate, a, b, c + 1, best, &diff,
1242 				 reg))
1243 			return;
1244 	}
1245 }
1246 
1247 static int hss_hdlc_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
1248 {
1249 	const size_t size = sizeof(sync_serial_settings);
1250 	sync_serial_settings new_line;
1251 	sync_serial_settings __user *line = ifr->ifr_settings.ifs_ifsu.sync;
1252 	struct port *port = dev_to_port(dev);
1253 	unsigned long flags;
1254 	int clk;
1255 
1256 	if (cmd != SIOCWANDEV)
1257 		return hdlc_ioctl(dev, ifr, cmd);
1258 
1259 	switch(ifr->ifr_settings.type) {
1260 	case IF_GET_IFACE:
1261 		ifr->ifr_settings.type = IF_IFACE_V35;
1262 		if (ifr->ifr_settings.size < size) {
1263 			ifr->ifr_settings.size = size; /* data size wanted */
1264 			return -ENOBUFS;
1265 		}
1266 		memset(&new_line, 0, sizeof(new_line));
1267 		new_line.clock_type = port->clock_type;
1268 		new_line.clock_rate = port->clock_rate;
1269 		new_line.loopback = port->loopback;
1270 		if (copy_to_user(line, &new_line, size))
1271 			return -EFAULT;
1272 		return 0;
1273 
1274 	case IF_IFACE_SYNC_SERIAL:
1275 	case IF_IFACE_V35:
1276 		if(!capable(CAP_NET_ADMIN))
1277 			return -EPERM;
1278 		if (copy_from_user(&new_line, line, size))
1279 			return -EFAULT;
1280 
1281 		clk = new_line.clock_type;
1282 		if (port->plat->set_clock)
1283 			clk = port->plat->set_clock(port->id, clk);
1284 
1285 		if (clk != CLOCK_EXT && clk != CLOCK_INT)
1286 			return -EINVAL;	/* No such clock setting */
1287 
1288 		if (new_line.loopback != 0 && new_line.loopback != 1)
1289 			return -EINVAL;
1290 
1291 		port->clock_type = clk; /* Update settings */
1292 		if (clk == CLOCK_INT)
1293 			find_best_clock(port->plat->timer_freq,
1294 					new_line.clock_rate,
1295 					&port->clock_rate, &port->clock_reg);
1296 		else {
1297 			port->clock_rate = 0;
1298 			port->clock_reg = CLK42X_SPEED_2048KHZ;
1299 		}
1300 		port->loopback = new_line.loopback;
1301 
1302 		spin_lock_irqsave(&npe_lock, flags);
1303 
1304 		if (dev->flags & IFF_UP)
1305 			hss_config(port);
1306 
1307 		if (port->loopback || port->carrier)
1308 			netif_carrier_on(port->netdev);
1309 		else
1310 			netif_carrier_off(port->netdev);
1311 		spin_unlock_irqrestore(&npe_lock, flags);
1312 
1313 		return 0;
1314 
1315 	default:
1316 		return hdlc_ioctl(dev, ifr, cmd);
1317 	}
1318 }
1319 
1320 /*****************************************************************************
1321  * initialization
1322  ****************************************************************************/
1323 
1324 static const struct net_device_ops hss_hdlc_ops = {
1325 	.ndo_open       = hss_hdlc_open,
1326 	.ndo_stop       = hss_hdlc_close,
1327 	.ndo_start_xmit = hdlc_start_xmit,
1328 	.ndo_do_ioctl   = hss_hdlc_ioctl,
1329 };
1330 
1331 static int hss_init_one(struct platform_device *pdev)
1332 {
1333 	struct port *port;
1334 	struct net_device *dev;
1335 	hdlc_device *hdlc;
1336 	int err;
1337 
1338 	if ((port = kzalloc(sizeof(*port), GFP_KERNEL)) == NULL)
1339 		return -ENOMEM;
1340 
1341 	if ((port->npe = npe_request(0)) == NULL) {
1342 		err = -ENODEV;
1343 		goto err_free;
1344 	}
1345 
1346 	if ((port->netdev = dev = alloc_hdlcdev(port)) == NULL) {
1347 		err = -ENOMEM;
1348 		goto err_plat;
1349 	}
1350 
1351 	SET_NETDEV_DEV(dev, &pdev->dev);
1352 	hdlc = dev_to_hdlc(dev);
1353 	hdlc->attach = hss_hdlc_attach;
1354 	hdlc->xmit = hss_hdlc_xmit;
1355 	dev->netdev_ops = &hss_hdlc_ops;
1356 	dev->tx_queue_len = 100;
1357 	port->clock_type = CLOCK_EXT;
1358 	port->clock_rate = 0;
1359 	port->clock_reg = CLK42X_SPEED_2048KHZ;
1360 	port->id = pdev->id;
1361 	port->dev = &pdev->dev;
1362 	port->plat = pdev->dev.platform_data;
1363 	netif_napi_add(dev, &port->napi, hss_hdlc_poll, NAPI_WEIGHT);
1364 
1365 	if ((err = register_hdlc_device(dev)))
1366 		goto err_free_netdev;
1367 
1368 	platform_set_drvdata(pdev, port);
1369 
1370 	netdev_info(dev, "initialized\n");
1371 	return 0;
1372 
1373 err_free_netdev:
1374 	free_netdev(dev);
1375 err_plat:
1376 	npe_release(port->npe);
1377 err_free:
1378 	kfree(port);
1379 	return err;
1380 }
1381 
1382 static int hss_remove_one(struct platform_device *pdev)
1383 {
1384 	struct port *port = platform_get_drvdata(pdev);
1385 
1386 	unregister_hdlc_device(port->netdev);
1387 	free_netdev(port->netdev);
1388 	npe_release(port->npe);
1389 	kfree(port);
1390 	return 0;
1391 }
1392 
1393 static struct platform_driver ixp4xx_hss_driver = {
1394 	.driver.name	= DRV_NAME,
1395 	.probe		= hss_init_one,
1396 	.remove		= hss_remove_one,
1397 };
1398 
1399 static int __init hss_init_module(void)
1400 {
1401 	if ((ixp4xx_read_feature_bits() &
1402 	     (IXP4XX_FEATURE_HDLC | IXP4XX_FEATURE_HSS)) !=
1403 	    (IXP4XX_FEATURE_HDLC | IXP4XX_FEATURE_HSS))
1404 		return -ENODEV;
1405 
1406 	return platform_driver_register(&ixp4xx_hss_driver);
1407 }
1408 
1409 static void __exit hss_cleanup_module(void)
1410 {
1411 	platform_driver_unregister(&ixp4xx_hss_driver);
1412 }
1413 
1414 MODULE_AUTHOR("Krzysztof Halasa");
1415 MODULE_DESCRIPTION("Intel IXP4xx HSS driver");
1416 MODULE_LICENSE("GPL v2");
1417 MODULE_ALIAS("platform:ixp4xx_hss");
1418 module_init(hss_init_module);
1419 module_exit(hss_cleanup_module);
1420