xref: /openbmc/linux/drivers/dma/bestcomm/fec.c (revision aa74c44b)
1 /*
2  * Bestcomm FEC tasks driver
3  *
4  *
5  * Copyright (C) 2006-2007 Sylvain Munaut <tnt@246tNt.com>
6  * Copyright (C) 2003-2004 MontaVista, Software, Inc.
7  *                         ( by Dale Farnsworth <dfarnsworth@mvista.com> )
8  *
9  * This file is licensed under the terms of the GNU General Public License
10  * version 2. This program is licensed "as is" without any warranty of any
11  * kind, whether express or implied.
12  */
13 
14 #include <linux/kernel.h>
15 #include <linux/module.h>
16 #include <linux/types.h>
17 #include <asm/io.h>
18 
19 #include <linux/fsl/bestcomm/bestcomm.h>
20 #include <linux/fsl/bestcomm/bestcomm_priv.h>
21 #include <linux/fsl/bestcomm/fec.h>
22 
23 
24 /* ======================================================================== */
25 /* Task image/var/inc                                                       */
26 /* ======================================================================== */
27 
28 /* fec tasks images */
29 extern u32 bcom_fec_rx_task[];
30 extern u32 bcom_fec_tx_task[];
31 
32 /* rx task vars that need to be set before enabling the task */
33 struct bcom_fec_rx_var {
34 	u32 enable;		/* (u16*) address of task's control register */
35 	u32 fifo;		/* (u32*) address of fec's fifo */
36 	u32 bd_base;		/* (struct bcom_bd*) beginning of ring buffer */
37 	u32 bd_last;		/* (struct bcom_bd*) end of ring buffer */
38 	u32 bd_start;		/* (struct bcom_bd*) current bd */
39 	u32 buffer_size;	/* size of receive buffer */
40 };
41 
42 /* rx task incs that need to be set before enabling the task */
43 struct bcom_fec_rx_inc {
44 	u16 pad0;
45 	s16 incr_bytes;
46 	u16 pad1;
47 	s16 incr_dst;
48 	u16 pad2;
49 	s16 incr_dst_ma;
50 };
51 
52 /* tx task vars that need to be set before enabling the task */
53 struct bcom_fec_tx_var {
54 	u32 DRD;		/* (u32*) address of self-modified DRD */
55 	u32 fifo;		/* (u32*) address of fec's fifo */
56 	u32 enable;		/* (u16*) address of task's control register */
57 	u32 bd_base;		/* (struct bcom_bd*) beginning of ring buffer */
58 	u32 bd_last;		/* (struct bcom_bd*) end of ring buffer */
59 	u32 bd_start;		/* (struct bcom_bd*) current bd */
60 	u32 buffer_size;	/* set by uCode for each packet */
61 };
62 
63 /* tx task incs that need to be set before enabling the task */
64 struct bcom_fec_tx_inc {
65 	u16 pad0;
66 	s16 incr_bytes;
67 	u16 pad1;
68 	s16 incr_src;
69 	u16 pad2;
70 	s16 incr_src_ma;
71 };
72 
73 /* private structure in the task */
74 struct bcom_fec_priv {
75 	phys_addr_t	fifo;
76 	int		maxbufsize;
77 };
78 
79 
80 /* ======================================================================== */
81 /* Task support code                                                        */
82 /* ======================================================================== */
83 
84 struct bcom_task *
85 bcom_fec_rx_init(int queue_len, phys_addr_t fifo, int maxbufsize)
86 {
87 	struct bcom_task *tsk;
88 	struct bcom_fec_priv *priv;
89 
90 	tsk = bcom_task_alloc(queue_len, sizeof(struct bcom_fec_bd),
91 				sizeof(struct bcom_fec_priv));
92 	if (!tsk)
93 		return NULL;
94 
95 	tsk->flags = BCOM_FLAGS_NONE;
96 
97 	priv = tsk->priv;
98 	priv->fifo = fifo;
99 	priv->maxbufsize = maxbufsize;
100 
101 	if (bcom_fec_rx_reset(tsk)) {
102 		bcom_task_free(tsk);
103 		return NULL;
104 	}
105 
106 	return tsk;
107 }
108 EXPORT_SYMBOL_GPL(bcom_fec_rx_init);
109 
110 int
111 bcom_fec_rx_reset(struct bcom_task *tsk)
112 {
113 	struct bcom_fec_priv *priv = tsk->priv;
114 	struct bcom_fec_rx_var *var;
115 	struct bcom_fec_rx_inc *inc;
116 
117 	/* Shutdown the task */
118 	bcom_disable_task(tsk->tasknum);
119 
120 	/* Reset the microcode */
121 	var = (struct bcom_fec_rx_var *) bcom_task_var(tsk->tasknum);
122 	inc = (struct bcom_fec_rx_inc *) bcom_task_inc(tsk->tasknum);
123 
124 	if (bcom_load_image(tsk->tasknum, bcom_fec_rx_task))
125 		return -1;
126 
127 	var->enable	= bcom_eng->regs_base +
128 				offsetof(struct mpc52xx_sdma, tcr[tsk->tasknum]);
129 	var->fifo	= (u32) priv->fifo;
130 	var->bd_base	= tsk->bd_pa;
131 	var->bd_last	= tsk->bd_pa + ((tsk->num_bd-1) * tsk->bd_size);
132 	var->bd_start	= tsk->bd_pa;
133 	var->buffer_size = priv->maxbufsize;
134 
135 	inc->incr_bytes	= -(s16)sizeof(u32);	/* These should be in the   */
136 	inc->incr_dst	= sizeof(u32);		/* task image, but we stick */
137 	inc->incr_dst_ma= sizeof(u8);		/* to the official ones     */
138 
139 	/* Reset the BDs */
140 	tsk->index = 0;
141 	tsk->outdex = 0;
142 
143 	memset_io(tsk->bd, 0x00, tsk->num_bd * tsk->bd_size);
144 
145 	/* Configure some stuff */
146 	bcom_set_task_pragma(tsk->tasknum, BCOM_FEC_RX_BD_PRAGMA);
147 	bcom_set_task_auto_start(tsk->tasknum, tsk->tasknum);
148 
149 	out_8(&bcom_eng->regs->ipr[BCOM_INITIATOR_FEC_RX], BCOM_IPR_FEC_RX);
150 
151 	out_be32(&bcom_eng->regs->IntPend, 1<<tsk->tasknum);	/* Clear ints */
152 
153 	return 0;
154 }
155 EXPORT_SYMBOL_GPL(bcom_fec_rx_reset);
156 
157 void
158 bcom_fec_rx_release(struct bcom_task *tsk)
159 {
160 	/* Nothing special for the FEC tasks */
161 	bcom_task_free(tsk);
162 }
163 EXPORT_SYMBOL_GPL(bcom_fec_rx_release);
164 
165 
166 
167 	/* Return 2nd to last DRD */
168 	/* This is an ugly hack, but at least it's only done
169 	   once at initialization */
170 static u32 *self_modified_drd(int tasknum)
171 {
172 	u32 *desc;
173 	int num_descs;
174 	int drd_count;
175 	int i;
176 
177 	num_descs = bcom_task_num_descs(tasknum);
178 	desc = bcom_task_desc(tasknum) + num_descs - 1;
179 	drd_count = 0;
180 	for (i=0; i<num_descs; i++, desc--)
181 		if (bcom_desc_is_drd(*desc) && ++drd_count == 3)
182 			break;
183 	return desc;
184 }
185 
186 struct bcom_task *
187 bcom_fec_tx_init(int queue_len, phys_addr_t fifo)
188 {
189 	struct bcom_task *tsk;
190 	struct bcom_fec_priv *priv;
191 
192 	tsk = bcom_task_alloc(queue_len, sizeof(struct bcom_fec_bd),
193 				sizeof(struct bcom_fec_priv));
194 	if (!tsk)
195 		return NULL;
196 
197 	tsk->flags = BCOM_FLAGS_ENABLE_TASK;
198 
199 	priv = tsk->priv;
200 	priv->fifo = fifo;
201 
202 	if (bcom_fec_tx_reset(tsk)) {
203 		bcom_task_free(tsk);
204 		return NULL;
205 	}
206 
207 	return tsk;
208 }
209 EXPORT_SYMBOL_GPL(bcom_fec_tx_init);
210 
211 int
212 bcom_fec_tx_reset(struct bcom_task *tsk)
213 {
214 	struct bcom_fec_priv *priv = tsk->priv;
215 	struct bcom_fec_tx_var *var;
216 	struct bcom_fec_tx_inc *inc;
217 
218 	/* Shutdown the task */
219 	bcom_disable_task(tsk->tasknum);
220 
221 	/* Reset the microcode */
222 	var = (struct bcom_fec_tx_var *) bcom_task_var(tsk->tasknum);
223 	inc = (struct bcom_fec_tx_inc *) bcom_task_inc(tsk->tasknum);
224 
225 	if (bcom_load_image(tsk->tasknum, bcom_fec_tx_task))
226 		return -1;
227 
228 	var->enable	= bcom_eng->regs_base +
229 				offsetof(struct mpc52xx_sdma, tcr[tsk->tasknum]);
230 	var->fifo	= (u32) priv->fifo;
231 	var->DRD	= bcom_sram_va2pa(self_modified_drd(tsk->tasknum));
232 	var->bd_base	= tsk->bd_pa;
233 	var->bd_last	= tsk->bd_pa + ((tsk->num_bd-1) * tsk->bd_size);
234 	var->bd_start	= tsk->bd_pa;
235 
236 	inc->incr_bytes	= -(s16)sizeof(u32);	/* These should be in the   */
237 	inc->incr_src	= sizeof(u32);		/* task image, but we stick */
238 	inc->incr_src_ma= sizeof(u8);		/* to the official ones     */
239 
240 	/* Reset the BDs */
241 	tsk->index = 0;
242 	tsk->outdex = 0;
243 
244 	memset_io(tsk->bd, 0x00, tsk->num_bd * tsk->bd_size);
245 
246 	/* Configure some stuff */
247 	bcom_set_task_pragma(tsk->tasknum, BCOM_FEC_TX_BD_PRAGMA);
248 	bcom_set_task_auto_start(tsk->tasknum, tsk->tasknum);
249 
250 	out_8(&bcom_eng->regs->ipr[BCOM_INITIATOR_FEC_TX], BCOM_IPR_FEC_TX);
251 
252 	out_be32(&bcom_eng->regs->IntPend, 1<<tsk->tasknum);	/* Clear ints */
253 
254 	return 0;
255 }
256 EXPORT_SYMBOL_GPL(bcom_fec_tx_reset);
257 
258 void
259 bcom_fec_tx_release(struct bcom_task *tsk)
260 {
261 	/* Nothing special for the FEC tasks */
262 	bcom_task_free(tsk);
263 }
264 EXPORT_SYMBOL_GPL(bcom_fec_tx_release);
265 
266 
267 MODULE_DESCRIPTION("BestComm FEC tasks driver");
268 MODULE_AUTHOR("Dale Farnsworth <dfarnsworth@mvista.com>");
269 MODULE_LICENSE("GPL v2");
270 
271