4a7d666a72
Previously we had two Koptions to decide if the stmmac had to use either a ring or a chain to manage its descriptors. This patch removes the Kernel configuration options and it allow us to use the chain mode by passing a module option. Ring mode continues to be the default. Also with this patch, it will be easier to validate the driver built and guarantee that all the two modes always compile fine. Signed-off-by: Giuseppe Cavallaro <peppe.cavallaro@st.com> Signed-off-by: David S. Miller <davem@davemloft.net>
122 lines
3.5 KiB
C
122 lines
3.5 KiB
C
/*******************************************************************************
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Specialised functions for managing Ring mode
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Copyright(C) 2011 STMicroelectronics Ltd
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It defines all the functions used to handle the normal/enhanced
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descriptors in case of the DMA is configured to work in chained or
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in ring mode.
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This program is free software; you can redistribute it and/or modify it
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under the terms and conditions of the GNU General Public License,
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version 2, as published by the Free Software Foundation.
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This program is distributed in the hope it will be useful, but WITHOUT
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ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
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more details.
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You should have received a copy of the GNU General Public License along with
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this program; if not, write to the Free Software Foundation, Inc.,
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51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
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The full GNU General Public License is included in this distribution in
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the file called "COPYING".
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Author: Giuseppe Cavallaro <peppe.cavallaro@st.com>
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*******************************************************************************/
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#include "stmmac.h"
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static unsigned int stmmac_jumbo_frm(void *p, struct sk_buff *skb, int csum)
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{
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struct stmmac_priv *priv = (struct stmmac_priv *) p;
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unsigned int txsize = priv->dma_tx_size;
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unsigned int entry = priv->cur_tx % txsize;
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struct dma_desc *desc = priv->dma_tx + entry;
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unsigned int nopaged_len = skb_headlen(skb);
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unsigned int bmax, len;
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if (priv->plat->enh_desc)
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bmax = BUF_SIZE_8KiB;
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else
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bmax = BUF_SIZE_2KiB;
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len = nopaged_len - bmax;
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if (nopaged_len > BUF_SIZE_8KiB) {
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desc->des2 = dma_map_single(priv->device, skb->data,
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bmax, DMA_TO_DEVICE);
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desc->des3 = desc->des2 + BUF_SIZE_4KiB;
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priv->hw->desc->prepare_tx_desc(desc, 1, bmax, csum,
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STMMAC_RING_MODE);
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wmb();
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entry = (++priv->cur_tx) % txsize;
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desc = priv->dma_tx + entry;
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desc->des2 = dma_map_single(priv->device, skb->data + bmax,
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len, DMA_TO_DEVICE);
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desc->des3 = desc->des2 + BUF_SIZE_4KiB;
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priv->hw->desc->prepare_tx_desc(desc, 0, len, csum,
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STMMAC_RING_MODE);
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wmb();
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priv->hw->desc->set_tx_owner(desc);
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priv->tx_skbuff[entry] = NULL;
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} else {
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desc->des2 = dma_map_single(priv->device, skb->data,
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nopaged_len, DMA_TO_DEVICE);
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desc->des3 = desc->des2 + BUF_SIZE_4KiB;
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priv->hw->desc->prepare_tx_desc(desc, 1, nopaged_len, csum,
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STMMAC_RING_MODE);
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}
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return entry;
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}
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static unsigned int stmmac_is_jumbo_frm(int len, int enh_desc)
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{
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unsigned int ret = 0;
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if (len >= BUF_SIZE_4KiB)
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ret = 1;
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return ret;
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}
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static void stmmac_refill_desc3(int bfsize, struct dma_desc *p)
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{
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/* Fill DES3 in case of RING mode */
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if (bfsize >= BUF_SIZE_8KiB)
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p->des3 = p->des2 + BUF_SIZE_8KiB;
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}
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/* In ring mode we need to fill the desc3 because it is used as buffer */
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static void stmmac_init_desc3(struct dma_desc *p)
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{
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p->des3 = p->des2 + BUF_SIZE_8KiB;
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}
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static void stmmac_clean_desc3(struct dma_desc *p)
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{
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if (unlikely(p->des3))
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p->des3 = 0;
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}
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static int stmmac_set_16kib_bfsize(int mtu)
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{
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int ret = 0;
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if (unlikely(mtu >= BUF_SIZE_8KiB))
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ret = BUF_SIZE_16KiB;
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return ret;
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}
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const struct stmmac_ring_mode_ops ring_mode_ops = {
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.is_jumbo_frm = stmmac_is_jumbo_frm,
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.jumbo_frm = stmmac_jumbo_frm,
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.refill_desc3 = stmmac_refill_desc3,
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.init_desc3 = stmmac_init_desc3,
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.clean_desc3 = stmmac_clean_desc3,
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.set_16kib_bfsize = stmmac_set_16kib_bfsize,
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};
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