| /******************************************************************************* |
| Specialised functions for managing Chained mode |
| |
| Copyright(C) 2011 STMicroelectronics Ltd |
| |
| It defines all the functions used to handle the normal/enhanced |
| descriptors in case of the DMA is configured to work in chained or |
| in ring mode. |
| |
| This program is free software; you can redistribute it and/or modify it |
| under the terms and conditions of the GNU General Public License, |
| version 2, as published by the Free Software Foundation. |
| |
| This program is distributed in the hope it will be useful, but WITHOUT |
| ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for |
| more details. |
| |
| You should have received a copy of the GNU General Public License along with |
| this program; if not, write to the Free Software Foundation, Inc., |
| 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA. |
| |
| The full GNU General Public License is included in this distribution in |
| the file called "COPYING". |
| |
| Author: Giuseppe Cavallaro <peppe.cavallaro@st.com> |
| *******************************************************************************/ |
| |
| #include "stmmac.h" |
| |
| static unsigned int stmmac_jumbo_frm(void *p, struct sk_buff *skb, int csum) |
| { |
| struct stmmac_priv *priv = (struct stmmac_priv *)p; |
| unsigned int txsize = priv->dma_tx_size; |
| unsigned int entry = priv->cur_tx % txsize; |
| struct dma_desc *desc = priv->dma_tx + entry; |
| unsigned int nopaged_len = skb_headlen(skb); |
| unsigned int bmax; |
| unsigned int i = 1, len; |
| |
| if (priv->plat->enh_desc) |
| bmax = BUF_SIZE_8KiB; |
| else |
| bmax = BUF_SIZE_2KiB; |
| |
| len = nopaged_len - bmax; |
| |
| desc->des2 = dma_map_single(priv->device, skb->data, |
| bmax, DMA_TO_DEVICE); |
| priv->tx_skbuff_dma[entry] = desc->des2; |
| priv->hw->desc->prepare_tx_desc(desc, 1, bmax, csum, STMMAC_CHAIN_MODE); |
| |
| while (len != 0) { |
| entry = (++priv->cur_tx) % txsize; |
| desc = priv->dma_tx + entry; |
| |
| if (len > bmax) { |
| desc->des2 = dma_map_single(priv->device, |
| (skb->data + bmax * i), |
| bmax, DMA_TO_DEVICE); |
| priv->tx_skbuff_dma[entry] = desc->des2; |
| priv->hw->desc->prepare_tx_desc(desc, 0, bmax, csum, |
| STMMAC_CHAIN_MODE); |
| priv->hw->desc->set_tx_owner(desc); |
| priv->tx_skbuff[entry] = NULL; |
| len -= bmax; |
| i++; |
| } else { |
| desc->des2 = dma_map_single(priv->device, |
| (skb->data + bmax * i), len, |
| DMA_TO_DEVICE); |
| priv->tx_skbuff_dma[entry] = desc->des2; |
| priv->hw->desc->prepare_tx_desc(desc, 0, len, csum, |
| STMMAC_CHAIN_MODE); |
| priv->hw->desc->set_tx_owner(desc); |
| priv->tx_skbuff[entry] = NULL; |
| len = 0; |
| } |
| } |
| return entry; |
| } |
| |
| static unsigned int stmmac_is_jumbo_frm(int len, int enh_desc) |
| { |
| unsigned int ret = 0; |
| |
| if ((enh_desc && (len > BUF_SIZE_8KiB)) || |
| (!enh_desc && (len > BUF_SIZE_2KiB))) { |
| ret = 1; |
| } |
| |
| return ret; |
| } |
| |
| static void stmmac_init_dma_chain(void *des, dma_addr_t phy_addr, |
| unsigned int size, unsigned int extend_desc) |
| { |
| /* |
| * In chained mode the des3 points to the next element in the ring. |
| * The latest element has to point to the head. |
| */ |
| int i; |
| dma_addr_t dma_phy = phy_addr; |
| |
| if (extend_desc) { |
| struct dma_extended_desc *p = (struct dma_extended_desc *)des; |
| for (i = 0; i < (size - 1); i++) { |
| dma_phy += sizeof(struct dma_extended_desc); |
| p->basic.des3 = (unsigned int)dma_phy; |
| p++; |
| } |
| p->basic.des3 = (unsigned int)phy_addr; |
| |
| } else { |
| struct dma_desc *p = (struct dma_desc *)des; |
| for (i = 0; i < (size - 1); i++) { |
| dma_phy += sizeof(struct dma_desc); |
| p->des3 = (unsigned int)dma_phy; |
| p++; |
| } |
| p->des3 = (unsigned int)phy_addr; |
| } |
| } |
| |
| static void stmmac_refill_desc3(void *priv_ptr, struct dma_desc *p) |
| { |
| struct stmmac_priv *priv = (struct stmmac_priv *)priv_ptr; |
| |
| if (priv->hwts_rx_en && !priv->extend_desc) |
| /* NOTE: Device will overwrite des3 with timestamp value if |
| * 1588-2002 time stamping is enabled, hence reinitialize it |
| * to keep explicit chaining in the descriptor. |
| */ |
| p->des3 = (unsigned int)(priv->dma_rx_phy + |
| (((priv->dirty_rx) + 1) % |
| priv->dma_rx_size) * |
| sizeof(struct dma_desc)); |
| } |
| |
| static void stmmac_clean_desc3(void *priv_ptr, struct dma_desc *p) |
| { |
| struct stmmac_priv *priv = (struct stmmac_priv *)priv_ptr; |
| |
| if (priv->hw->desc->get_tx_ls(p) && !priv->extend_desc) |
| /* NOTE: Device will overwrite des3 with timestamp value if |
| * 1588-2002 time stamping is enabled, hence reinitialize it |
| * to keep explicit chaining in the descriptor. |
| */ |
| p->des3 = (unsigned int)(priv->dma_tx_phy + |
| (((priv->dirty_tx + 1) % |
| priv->dma_tx_size) * |
| sizeof(struct dma_desc))); |
| } |
| |
| const struct stmmac_chain_mode_ops chain_mode_ops = { |
| .init = stmmac_init_dma_chain, |
| .is_jumbo_frm = stmmac_is_jumbo_frm, |
| .jumbo_frm = stmmac_jumbo_frm, |
| .refill_desc3 = stmmac_refill_desc3, |
| .clean_desc3 = stmmac_clean_desc3, |
| }; |