diff options
Diffstat (limited to 'drivers/net/ethernet/stmicro/stmmac/chain_mode.c')
| -rw-r--r-- | drivers/net/ethernet/stmicro/stmmac/chain_mode.c | 166 |
1 files changed, 166 insertions, 0 deletions
diff --git a/drivers/net/ethernet/stmicro/stmmac/chain_mode.c b/drivers/net/ethernet/stmicro/stmmac/chain_mode.c new file mode 100644 index 000000000..cf28daba4 --- /dev/null +++ b/drivers/net/ethernet/stmicro/stmmac/chain_mode.c @@ -0,0 +1,166 @@ +/******************************************************************************* + 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 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); + if (dma_mapping_error(priv->device, desc->des2)) + return -1; + priv->tx_skbuff_dma[entry].buf = desc->des2; + priv->hw->desc->prepare_tx_desc(desc, 1, bmax, csum, STMMAC_CHAIN_MODE); + + while (len != 0) { + priv->tx_skbuff[entry] = NULL; + 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); + if (dma_mapping_error(priv->device, desc->des2)) + return -1; + priv->tx_skbuff_dma[entry].buf = desc->des2; + priv->hw->desc->prepare_tx_desc(desc, 0, bmax, csum, + STMMAC_CHAIN_MODE); + priv->hw->desc->set_tx_owner(desc); + len -= bmax; + i++; + } else { + desc->des2 = dma_map_single(priv->device, + (skb->data + bmax * i), len, + DMA_TO_DEVICE); + if (dma_mapping_error(priv->device, desc->des2)) + return -1; + priv->tx_skbuff_dma[entry].buf = desc->des2; + priv->hw->desc->prepare_tx_desc(desc, 0, len, csum, + STMMAC_CHAIN_MODE); + priv->hw->desc->set_tx_owner(desc); + 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_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, +}; |