stmmac: code tidy-up
[cascardo/linux.git] / drivers / net / ethernet / stmicro / stmmac / norm_desc.c
1 /*******************************************************************************
2   This contains the functions to handle the normal descriptors.
3
4   Copyright (C) 2007-2009  STMicroelectronics Ltd
5
6   This program is free software; you can redistribute it and/or modify it
7   under the terms and conditions of the GNU General Public License,
8   version 2, as published by the Free Software Foundation.
9
10   This program is distributed in the hope it will be useful, but WITHOUT
11   ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12   FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
13   more details.
14
15   You should have received a copy of the GNU General Public License along with
16   this program; if not, write to the Free Software Foundation, Inc.,
17   51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
18
19   The full GNU General Public License is included in this distribution in
20   the file called "COPYING".
21
22   Author: Giuseppe Cavallaro <peppe.cavallaro@st.com>
23 *******************************************************************************/
24
25 #include <linux/stmmac.h>
26 #include "common.h"
27 #include "descs_com.h"
28
29 static int ndesc_get_tx_status(void *data, struct stmmac_extra_stats *x,
30                                struct dma_desc *p, void __iomem *ioaddr)
31 {
32         int ret = 0;
33         struct net_device_stats *stats = (struct net_device_stats *)data;
34
35         if (unlikely(p->des01.tx.error_summary)) {
36                 if (unlikely(p->des01.tx.underflow_error)) {
37                         x->tx_underflow++;
38                         stats->tx_fifo_errors++;
39                 }
40                 if (unlikely(p->des01.tx.no_carrier)) {
41                         x->tx_carrier++;
42                         stats->tx_carrier_errors++;
43                 }
44                 if (unlikely(p->des01.tx.loss_carrier)) {
45                         x->tx_losscarrier++;
46                         stats->tx_carrier_errors++;
47                 }
48                 if (unlikely((p->des01.tx.excessive_deferral) ||
49                              (p->des01.tx.excessive_collisions) ||
50                              (p->des01.tx.late_collision)))
51                         stats->collisions += p->des01.tx.collision_count;
52                 ret = -1;
53         }
54
55         if (p->des01.etx.vlan_frame) {
56                 CHIP_DBG(KERN_INFO "GMAC TX status: VLAN frame\n");
57                 x->tx_vlan++;
58         }
59
60         if (unlikely(p->des01.tx.deferred))
61                 x->tx_deferred++;
62
63         return ret;
64 }
65
66 static int ndesc_get_tx_len(struct dma_desc *p)
67 {
68         return p->des01.tx.buffer1_size;
69 }
70
71 /* This function verifies if each incoming frame has some errors
72  * and, if required, updates the multicast statistics.
73  * In case of success, it returns good_frame because the GMAC device
74  * is supposed to be able to compute the csum in HW. */
75 static int ndesc_get_rx_status(void *data, struct stmmac_extra_stats *x,
76                                struct dma_desc *p)
77 {
78         int ret = good_frame;
79         struct net_device_stats *stats = (struct net_device_stats *)data;
80
81         if (unlikely(p->des01.rx.last_descriptor == 0)) {
82                 pr_warn("%s: Oversized frame spanned multiple buffers\n",
83                         __func__);
84                 stats->rx_length_errors++;
85                 return discard_frame;
86         }
87
88         if (unlikely(p->des01.rx.error_summary)) {
89                 if (unlikely(p->des01.rx.descriptor_error))
90                         x->rx_desc++;
91                 if (unlikely(p->des01.rx.sa_filter_fail))
92                         x->sa_filter_fail++;
93                 if (unlikely(p->des01.rx.overflow_error))
94                         x->overflow_error++;
95                 if (unlikely(p->des01.rx.ipc_csum_error))
96                         x->ipc_csum_error++;
97                 if (unlikely(p->des01.rx.collision)) {
98                         x->rx_collision++;
99                         stats->collisions++;
100                 }
101                 if (unlikely(p->des01.rx.crc_error)) {
102                         x->rx_crc++;
103                         stats->rx_crc_errors++;
104                 }
105                 ret = discard_frame;
106         }
107         if (unlikely(p->des01.rx.dribbling))
108                 x->dribbling_bit++;
109
110         if (unlikely(p->des01.rx.length_error)) {
111                 x->rx_length++;
112                 ret = discard_frame;
113         }
114         if (unlikely(p->des01.rx.mii_error)) {
115                 x->rx_mii++;
116                 ret = discard_frame;
117         }
118 #ifdef STMMAC_VLAN_TAG_USED
119         if (p->des01.rx.vlan_tag)
120                 x->vlan_tag++;
121 #endif
122         return ret;
123 }
124
125 static void ndesc_init_rx_desc(struct dma_desc *p, int disable_rx_ic, int mode,
126                                int end)
127 {
128         p->des01.rx.own = 1;
129         p->des01.rx.buffer1_size = BUF_SIZE_2KiB - 1;
130
131         if (mode == STMMAC_CHAIN_MODE)
132                 ndesc_rx_set_on_chain(p, end);
133         else
134                 ndesc_rx_set_on_ring(p, end);
135
136         if (disable_rx_ic)
137                 p->des01.rx.disable_ic = 1;
138 }
139
140 static void ndesc_init_tx_desc(struct dma_desc *p, int mode, int end)
141 {
142         p->des01.tx.own = 0;
143         if (mode == STMMAC_CHAIN_MODE)
144                 ndesc_tx_set_on_chain(p, end);
145         else
146                 ndesc_tx_set_on_ring(p, end);
147 }
148
149 static int ndesc_get_tx_owner(struct dma_desc *p)
150 {
151         return p->des01.tx.own;
152 }
153
154 static int ndesc_get_rx_owner(struct dma_desc *p)
155 {
156         return p->des01.rx.own;
157 }
158
159 static void ndesc_set_tx_owner(struct dma_desc *p)
160 {
161         p->des01.tx.own = 1;
162 }
163
164 static void ndesc_set_rx_owner(struct dma_desc *p)
165 {
166         p->des01.rx.own = 1;
167 }
168
169 static int ndesc_get_tx_ls(struct dma_desc *p)
170 {
171         return p->des01.tx.last_segment;
172 }
173
174 static void ndesc_release_tx_desc(struct dma_desc *p, int mode)
175 {
176         int ter = p->des01.tx.end_ring;
177
178         memset(p, 0, offsetof(struct dma_desc, des2));
179         if (mode == STMMAC_CHAIN_MODE)
180                 ndesc_end_tx_desc_on_chain(p, ter);
181         else
182                 ndesc_end_tx_desc_on_ring(p, ter);
183 }
184
185 static void ndesc_prepare_tx_desc(struct dma_desc *p, int is_fs, int len,
186                                   int csum_flag, int mode)
187 {
188         p->des01.tx.first_segment = is_fs;
189         if (mode == STMMAC_CHAIN_MODE)
190                 norm_set_tx_desc_len_on_chain(p, len);
191         else
192                 norm_set_tx_desc_len_on_ring(p, len);
193
194         if (likely(csum_flag))
195                 p->des01.tx.checksum_insertion = cic_full;
196 }
197
198 static void ndesc_clear_tx_ic(struct dma_desc *p)
199 {
200         p->des01.tx.interrupt = 0;
201 }
202
203 static void ndesc_close_tx_desc(struct dma_desc *p)
204 {
205         p->des01.tx.last_segment = 1;
206         p->des01.tx.interrupt = 1;
207 }
208
209 static int ndesc_get_rx_frame_len(struct dma_desc *p, int rx_coe_type)
210 {
211         /* The type-1 checksum offload engines append the checksum at
212          * the end of frame and the two bytes of checksum are added in
213          * the length.
214          * Adjust for that in the framelen for type-1 checksum offload
215          * engines. */
216         if (rx_coe_type == STMMAC_RX_COE_TYPE1)
217                 return p->des01.rx.frame_length - 2;
218         else
219                 return p->des01.rx.frame_length;
220 }
221
222 static void ndesc_enable_tx_timestamp(struct dma_desc *p)
223 {
224         p->des01.tx.time_stamp_enable = 1;
225 }
226
227 static int ndesc_get_tx_timestamp_status(struct dma_desc *p)
228 {
229         return p->des01.tx.time_stamp_status;
230 }
231
232 static u64 ndesc_get_timestamp(void *desc, u32 ats)
233 {
234         struct dma_desc *p = (struct dma_desc *)desc;
235         u64 ns;
236
237         ns = p->des2;
238         /* convert high/sec time stamp value to nanosecond */
239         ns += p->des3 * 1000000000ULL;
240
241         return ns;
242 }
243
244 static int ndesc_get_rx_timestamp_status(void *desc, u32 ats)
245 {
246         struct dma_desc *p = (struct dma_desc *)desc;
247
248         if ((p->des2 == 0xffffffff) && (p->des3 == 0xffffffff))
249                 /* timestamp is corrupted, hence don't store it */
250                 return 0;
251         else
252                 return 1;
253 }
254
255 const struct stmmac_desc_ops ndesc_ops = {
256         .tx_status = ndesc_get_tx_status,
257         .rx_status = ndesc_get_rx_status,
258         .get_tx_len = ndesc_get_tx_len,
259         .init_rx_desc = ndesc_init_rx_desc,
260         .init_tx_desc = ndesc_init_tx_desc,
261         .get_tx_owner = ndesc_get_tx_owner,
262         .get_rx_owner = ndesc_get_rx_owner,
263         .release_tx_desc = ndesc_release_tx_desc,
264         .prepare_tx_desc = ndesc_prepare_tx_desc,
265         .clear_tx_ic = ndesc_clear_tx_ic,
266         .close_tx_desc = ndesc_close_tx_desc,
267         .get_tx_ls = ndesc_get_tx_ls,
268         .set_tx_owner = ndesc_set_tx_owner,
269         .set_rx_owner = ndesc_set_rx_owner,
270         .get_rx_frame_len = ndesc_get_rx_frame_len,
271         .enable_tx_timestamp = ndesc_enable_tx_timestamp,
272         .get_tx_timestamp_status = ndesc_get_tx_timestamp_status,
273         .get_timestamp = ndesc_get_timestamp,
274         .get_rx_timestamp_status = ndesc_get_rx_timestamp_status,
275 };