drivers/net/ethernet/stmicro/stmmac/descs_com.h

   1 /*******************************************************************************
   2   Header File to describe Normal/enhanced descriptor functions used for RING
   3   and CHAINED modes.
   4
   5   Copyright(C) 2011  STMicroelectronics Ltd
   6
   7   It defines all the functions used to handle the normal/enhanced
   8   descriptors in case of the DMA is configured to work in chained or
   9   in ring mode.
  10
  11   This program is free software; you can redistribute it and/or modify it
  12   under the terms and conditions of the GNU General Public License,
  13   version 2, as published by the Free Software Foundation.
  14
  15   This program is distributed in the hope it will be useful, but WITHOUT
  16   ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  17   FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  18   more details.
  19
  20   You should have received a copy of the GNU General Public License along with
  21   this program; if not, write to the Free Software Foundation, Inc.,
  22   51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
  23
  24   The full GNU General Public License is included in this distribution in
  25   the file called "COPYING".
  26
  27   Author: Giuseppe Cavallaro <peppe.cavallaro@st.com>
  28 *******************************************************************************/
  29
  30 #ifndef __DESC_COM_H__
  31 #define __DESC_COM_H__
  32
  33 /* Specific functions used for Ring mode */
  34
  35 /* Enhanced descriptors */
  36 static inline void ehn_desc_rx_set_on_ring(struct dma_desc *p, int end,
  37                                            int bfsize)
  38 {
  39         if (bfsize == BUF_SIZE_16KiB)
  40                 p->des1 |= cpu_to_le32((BUF_SIZE_8KiB
  41                                 << ERDES1_BUFFER2_SIZE_SHIFT)
  42                 & ERDES1_BUFFER2_SIZE_MASK);
  43
  44
  45         if (end)
  46                 p->des1 |= cpu_to_le32(ERDES1_END_RING);
  47 }
  48
  49 static inline void enh_desc_end_tx_desc_on_ring(struct dma_desc *p, int end)
  50 {
  51         if (end)
  52                 p->des0 |= cpu_to_le32(ETDES0_END_RING);
  53         else
  54                 p->des0 &= cpu_to_le32(~ETDES0_END_RING);
  55 }
  56
  57 static inline void enh_set_tx_desc_len_on_ring(struct dma_desc *p, int len)
  58 {
  59         if (unlikely(len > BUF_SIZE_4KiB)) {
  60                 p->des1 |= cpu_to_le32((((len - BUF_SIZE_4KiB)
  61                                         << ETDES1_BUFFER2_SIZE_SHIFT)
  62                             & ETDES1_BUFFER2_SIZE_MASK) | (BUF_SIZE_4KiB
  63                             & ETDES1_BUFFER1_SIZE_MASK));
  64         } else
  65                 p->des1 |= cpu_to_le32((len & ETDES1_BUFFER1_SIZE_MASK));
  66 }
  67
  68 /* Normal descriptors */
  69 static inline void ndesc_rx_set_on_ring(struct dma_desc *p, int end, int bfsize)
  70 {
  71         if (bfsize >= BUF_SIZE_2KiB) {
  72                 int bfsize2;
  73
  74                 bfsize2 = min(bfsize - BUF_SIZE_2KiB + 1, BUF_SIZE_2KiB - 1);
  75                 p->des1 |= cpu_to_le32((bfsize2 << RDES1_BUFFER2_SIZE_SHIFT)
  76                             & RDES1_BUFFER2_SIZE_MASK);
  77         }
  78
  79         if (end)
  80                 p->des1 |= cpu_to_le32(RDES1_END_RING);
  81 }
  82
  83 static inline void ndesc_end_tx_desc_on_ring(struct dma_desc *p, int end)
  84 {
  85         if (end)
  86                 p->des1 |= cpu_to_le32(TDES1_END_RING);
  87         else
  88                 p->des1 &= cpu_to_le32(~TDES1_END_RING);
  89 }
  90
  91 static inline void norm_set_tx_desc_len_on_ring(struct dma_desc *p, int len)
  92 {
  93         if (unlikely(len > BUF_SIZE_2KiB)) {
  94                 unsigned int buffer1 = (BUF_SIZE_2KiB - 1)
  95                                         & TDES1_BUFFER1_SIZE_MASK;
  96                 p->des1 |= cpu_to_le32((((len - buffer1)
  97                                         << TDES1_BUFFER2_SIZE_SHIFT)
  98                                 & TDES1_BUFFER2_SIZE_MASK) | buffer1);
  99         } else
 100                 p->des1 |= cpu_to_le32((len & TDES1_BUFFER1_SIZE_MASK));
 101 }
 102
 103 /* Specific functions used for Chain mode */
 104
 105 /* Enhanced descriptors */
 106 static inline void ehn_desc_rx_set_on_chain(struct dma_desc *p)
 107 {
 108         p->des1 |= cpu_to_le32(ERDES1_SECOND_ADDRESS_CHAINED);
 109 }
 110
 111 static inline void enh_desc_end_tx_desc_on_chain(struct dma_desc *p)
 112 {
 113         p->des0 |= cpu_to_le32(ETDES0_SECOND_ADDRESS_CHAINED);
 114 }
 115
 116 static inline void enh_set_tx_desc_len_on_chain(struct dma_desc *p, int len)
 117 {
 118         p->des1 |= cpu_to_le32(len & ETDES1_BUFFER1_SIZE_MASK);
 119 }
 120
 121 /* Normal descriptors */
 122 static inline void ndesc_rx_set_on_chain(struct dma_desc *p, int end)
 123 {
 124         p->des1 |= cpu_to_le32(RDES1_SECOND_ADDRESS_CHAINED);
 125 }
 126
 127 static inline void ndesc_tx_set_on_chain(struct dma_desc *p)
 128 {
 129         p->des1 |= cpu_to_le32(TDES1_SECOND_ADDRESS_CHAINED);
 130 }
 131
 132 static inline void norm_set_tx_desc_len_on_chain(struct dma_desc *p, int len)
 133 {
 134         p->des1 |= cpu_to_le32(len & TDES1_BUFFER1_SIZE_MASK);
 135 }
 136 #endif /* __DESC_COM_H__ */