[deliverable/linux.git] / drivers / net / ethernet / stmicro / stmmac / ring_mode.c

/*******************************************************************************
  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;
	unsigned int nopaged_len = skb_headlen(skb);
	unsigned int bmax, len;

	if (priv->extend_desc)
		desc = (struct dma_desc *)(priv->dma_etx + entry);
	else
		desc = priv->dma_tx + entry;

	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);
		priv->tx_skbuff_dma[entry] = desc->des2;
		desc->des3 = desc->des2 + BUF_SIZE_4KiB;
		priv->hw->desc->prepare_tx_desc(desc, 1, bmax, csum,
						STMMAC_RING_MODE);
		wmb();
		entry = (++priv->cur_tx) % txsize;

		if (priv->extend_desc)
			desc = (struct dma_desc *)(priv->dma_etx + entry);
		else
			desc = priv->dma_tx + entry;

		desc->des2 = dma_map_single(priv->device, skb->data + bmax,
					    len, DMA_TO_DEVICE);
		priv->tx_skbuff_dma[entry] = desc->des2;
		desc->des3 = desc->des2 + BUF_SIZE_4KiB;
		priv->hw->desc->prepare_tx_desc(desc, 0, len, csum,
						STMMAC_RING_MODE);
		wmb();
		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);
		priv->tx_skbuff_dma[entry] = desc->des2;
		desc->des3 = desc->des2 + BUF_SIZE_4KiB;
		priv->hw->desc->prepare_tx_desc(desc, 1, nopaged_len, csum,
						STMMAC_RING_MODE);
	}

	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(void *priv_ptr, struct dma_desc *p)
{
	struct stmmac_priv *priv = (struct stmmac_priv *)priv_ptr;

	if (unlikely(priv->plat->has_gmac))
		/* Fill DES3 in case of RING mode */
		if (priv->dma_buf_sz >= 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(struct dma_desc *p)
{
	p->des3 = p->des2 + BUF_SIZE_8KiB;
}

static void stmmac_clean_desc3(void *priv_ptr, 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,
	.clean_desc3 = stmmac_clean_desc3,
	.set_16kib_bfsize = stmmac_set_16kib_bfsize,
};
Commit	Line	Data
286a8372 GC	1	/*******************************************************************************
	2	Specialised functions for managing Ring mode
	3
	4	Copyright(C) 2011 STMicroelectronics Ltd
	5
	6	It defines all the functions used to handle the normal/enhanced
	7	descriptors in case of the DMA is configured to work in chained or
	8	in ring mode.
	9
	10	This program is free software; you can redistribute it and/or modify it
	11	under the terms and conditions of the GNU General Public License,
	12	version 2, as published by the Free Software Foundation.
	13
	14	This program is distributed in the hope it will be useful, but WITHOUT
	15	ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
	16	FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
	17	more details.
	18
	19	You should have received a copy of the GNU General Public License along with
	20	this program; if not, write to the Free Software Foundation, Inc.,
	21	51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
	22
	23	The full GNU General Public License is included in this distribution in
	24	the file called "COPYING".
	25
	26	Author: Giuseppe Cavallaro <peppe.cavallaro@st.com>
	27	*******************************************************************************/
	28
	29	#include "stmmac.h"
	30
	31	static unsigned int stmmac_jumbo_frm(void p, struct sk_buff skb, int csum)
	32	{
ceb69499	33	struct stmmac_priv priv = (struct stmmac_priv )p;
286a8372 GC	34	unsigned int txsize = priv->dma_tx_size;
286a8372 GC	35	unsigned int entry = priv->cur_tx % txsize;
21ff0193	36	struct dma_desc *desc;
286a8372 GC	37	unsigned int nopaged_len = skb_headlen(skb);
	38	unsigned int bmax, len;
	39
21ff0193 BA	40	if (priv->extend_desc)
	41	desc = (struct dma_desc *)(priv->dma_etx + entry);
	42	else
	43	desc = priv->dma_tx + entry;
	44
286a8372 GC	45	if (priv->plat->enh_desc)
	46	bmax = BUF_SIZE_8KiB;
	47	else
	48	bmax = BUF_SIZE_2KiB;
	49
	50	len = nopaged_len - bmax;
	51
	52	if (nopaged_len > BUF_SIZE_8KiB) {
	53
	54	desc->des2 = dma_map_single(priv->device, skb->data,
	55	bmax, DMA_TO_DEVICE);
cf32deec	56	priv->tx_skbuff_dma[entry] = desc->des2;
286a8372	57	desc->des3 = desc->des2 + BUF_SIZE_4KiB;
4a7d666a GC	58	priv->hw->desc->prepare_tx_desc(desc, 1, bmax, csum,
4a7d666a GC	59	STMMAC_RING_MODE);
684901a6	60	wmb();
286a8372	61	entry = (++priv->cur_tx) % txsize;
21ff0193 BA	62
	63	if (priv->extend_desc)
	64	desc = (struct dma_desc *)(priv->dma_etx + entry);
	65	else
	66	desc = priv->dma_tx + entry;
286a8372 GC	67
	68	desc->des2 = dma_map_single(priv->device, skb->data + bmax,
	69	len, DMA_TO_DEVICE);
cf32deec	70	priv->tx_skbuff_dma[entry] = desc->des2;
286a8372	71	desc->des3 = desc->des2 + BUF_SIZE_4KiB;
4a7d666a GC	72	priv->hw->desc->prepare_tx_desc(desc, 0, len, csum,
4a7d666a GC	73	STMMAC_RING_MODE);
684901a6	74	wmb();
286a8372 GC	75	priv->hw->desc->set_tx_owner(desc);
	76	priv->tx_skbuff[entry] = NULL;
	77	} else {
	78	desc->des2 = dma_map_single(priv->device, skb->data,
	79	nopaged_len, DMA_TO_DEVICE);
cf32deec	80	priv->tx_skbuff_dma[entry] = desc->des2;
286a8372	81	desc->des3 = desc->des2 + BUF_SIZE_4KiB;
4a7d666a GC	82	priv->hw->desc->prepare_tx_desc(desc, 1, nopaged_len, csum,
4a7d666a GC	83	STMMAC_RING_MODE);
286a8372 GC	84	}
	85
	86	return entry;
	87	}
	88
	89	static unsigned int stmmac_is_jumbo_frm(int len, int enh_desc)
	90	{
	91	unsigned int ret = 0;
	92
	93	if (len >= BUF_SIZE_4KiB)
	94	ret = 1;
	95
	96	return ret;
	97	}
	98
891434b1	99	static void stmmac_refill_desc3(void priv_ptr, struct dma_desc p)
286a8372	100	{
891434b1 RK	101	struct stmmac_priv priv = (struct stmmac_priv )priv_ptr;
	102
	103	if (unlikely(priv->plat->has_gmac))
	104	/* Fill DES3 in case of RING mode */
	105	if (priv->dma_buf_sz >= BUF_SIZE_8KiB)
	106	p->des3 = p->des2 + BUF_SIZE_8KiB;
286a8372 GC	107	}
286a8372 GC	108
4a7d666a GC	109	/* In ring mode we need to fill the desc3 because it is used as buffer */
4a7d666a GC	110	static void stmmac_init_desc3(struct dma_desc *p)
286a8372	111	{
4a7d666a	112	p->des3 = p->des2 + BUF_SIZE_8KiB;
286a8372 GC	113	}
286a8372 GC	114
891434b1	115	static void stmmac_clean_desc3(void priv_ptr, struct dma_desc p)
286a8372 GC	116	{
	117	if (unlikely(p->des3))
	118	p->des3 = 0;
	119	}
	120
	121	static int stmmac_set_16kib_bfsize(int mtu)
	122	{
	123	int ret = 0;
	124	if (unlikely(mtu >= BUF_SIZE_8KiB))
	125	ret = BUF_SIZE_16KiB;
	126	return ret;
	127	}
	128
	129	const struct stmmac_ring_mode_ops ring_mode_ops = {
	130	.is_jumbo_frm = stmmac_is_jumbo_frm,
	131	.jumbo_frm = stmmac_jumbo_frm,
	132	.refill_desc3 = stmmac_refill_desc3,
	133	.init_desc3 = stmmac_init_desc3,
286a8372 GC	134	.clean_desc3 = stmmac_clean_desc3,
	135	.set_16kib_bfsize = stmmac_set_16kib_bfsize,
	136	};