diff options
Diffstat (limited to 'drivers/net/ethernet/stmicro/stmmac/ring_mode.c')
| -rw-r--r-- | drivers/net/ethernet/stmicro/stmmac/ring_mode.c | 126 |
1 files changed, 126 insertions, 0 deletions
diff --git a/drivers/net/ethernet/stmicro/stmmac/ring_mode.c b/drivers/net/ethernet/stmicro/stmmac/ring_mode.c new file mode 100644 index 00000000000..fb8377da168 --- /dev/null +++ b/drivers/net/ethernet/stmicro/stmmac/ring_mode.c @@ -0,0 +1,126 @@ +/******************************************************************************* + Specialised functions for managing Ring 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, len; + + if (priv->plat->enh_desc) + bmax = BUF_SIZE_8KiB; + else + bmax = BUF_SIZE_2KiB; + + len = nopaged_len - bmax; + + if (nopaged_len > BUF_SIZE_8KiB) { + + desc->des2 = dma_map_single(priv->device, skb->data, + bmax, DMA_TO_DEVICE); + desc->des3 = desc->des2 + BUF_SIZE_4KiB; + priv->hw->desc->prepare_tx_desc(desc, 1, bmax, + csum); + + entry = (++priv->cur_tx) % txsize; + desc = priv->dma_tx + entry; + + desc->des2 = dma_map_single(priv->device, skb->data + bmax, + len, DMA_TO_DEVICE); + desc->des3 = desc->des2 + BUF_SIZE_4KiB; + priv->hw->desc->prepare_tx_desc(desc, 0, len, csum); + priv->hw->desc->set_tx_owner(desc); + priv->tx_skbuff[entry] = NULL; + } else { + desc->des2 = dma_map_single(priv->device, skb->data, + nopaged_len, DMA_TO_DEVICE); + desc->des3 = desc->des2 + BUF_SIZE_4KiB; + priv->hw->desc->prepare_tx_desc(desc, 1, nopaged_len, csum); + } + + return entry; +} + +static unsigned int stmmac_is_jumbo_frm(int len, int enh_desc) +{ + unsigned int ret = 0; + + if (len >= BUF_SIZE_4KiB) + ret = 1; + + return ret; +} + +static void stmmac_refill_desc3(int bfsize, struct dma_desc *p) +{ + /* Fill DES3 in case of RING mode */ + if (bfsize >= BUF_SIZE_8KiB) + p->des3 = p->des2 + BUF_SIZE_8KiB; +} + +/* In ring mode we need to fill the desc3 because it is used + * as buffer */ +static void stmmac_init_desc3(int des3_as_data_buf, struct dma_desc *p) +{ + if (unlikely(des3_as_data_buf)) + p->des3 = p->des2 + BUF_SIZE_8KiB; +} + +static void stmmac_init_dma_chain(struct dma_desc *des, dma_addr_t phy_addr, + unsigned int size) +{ +} + +static void stmmac_clean_desc3(struct dma_desc *p) +{ + if (unlikely(p->des3)) + p->des3 = 0; +} + +static int stmmac_set_16kib_bfsize(int mtu) +{ + int ret = 0; + if (unlikely(mtu >= BUF_SIZE_8KiB)) + ret = BUF_SIZE_16KiB; + return ret; +} + +const struct stmmac_ring_mode_ops ring_mode_ops = { + .is_jumbo_frm = stmmac_is_jumbo_frm, + .jumbo_frm = stmmac_jumbo_frm, + .refill_desc3 = stmmac_refill_desc3, + .init_desc3 = stmmac_init_desc3, + .init_dma_chain = stmmac_init_dma_chain, + .clean_desc3 = stmmac_clean_desc3, + .set_16kib_bfsize = stmmac_set_16kib_bfsize, +}; |