147 lines
		
	
	
		
			4.0 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			147 lines
		
	
	
		
			4.0 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| // SPDX-License-Identifier: GPL-2.0-only
 | |
| /*******************************************************************************
 | |
|   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.
 | |
| 
 | |
| 
 | |
|   Author: Giuseppe Cavallaro <peppe.cavallaro@st.com>
 | |
| *******************************************************************************/
 | |
| 
 | |
| #include "stmmac.h"
 | |
| 
 | |
| static int jumbo_frm(struct stmmac_tx_queue *tx_q, struct sk_buff *skb,
 | |
| 		     int csum)
 | |
| {
 | |
| 	unsigned int nopaged_len = skb_headlen(skb);
 | |
| 	struct stmmac_priv *priv = tx_q->priv_data;
 | |
| 	unsigned int entry = tx_q->cur_tx;
 | |
| 	unsigned int bmax, len, des2;
 | |
| 	struct dma_desc *desc;
 | |
| 
 | |
| 	if (priv->extend_desc)
 | |
| 		desc = (struct dma_desc *)(tx_q->dma_etx + entry);
 | |
| 	else
 | |
| 		desc = tx_q->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) {
 | |
| 
 | |
| 		des2 = dma_map_single(priv->device, skb->data, bmax,
 | |
| 				      DMA_TO_DEVICE);
 | |
| 		desc->des2 = cpu_to_le32(des2);
 | |
| 		if (dma_mapping_error(priv->device, des2))
 | |
| 			return -1;
 | |
| 
 | |
| 		tx_q->tx_skbuff_dma[entry].buf = des2;
 | |
| 		tx_q->tx_skbuff_dma[entry].len = bmax;
 | |
| 		tx_q->tx_skbuff_dma[entry].is_jumbo = true;
 | |
| 
 | |
| 		desc->des3 = cpu_to_le32(des2 + BUF_SIZE_4KiB);
 | |
| 		stmmac_prepare_tx_desc(priv, desc, 1, bmax, csum,
 | |
| 				STMMAC_RING_MODE, 0, false, skb->len);
 | |
| 		tx_q->tx_skbuff[entry] = NULL;
 | |
| 		entry = STMMAC_GET_ENTRY(entry, priv->dma_conf.dma_tx_size);
 | |
| 
 | |
| 		if (priv->extend_desc)
 | |
| 			desc = (struct dma_desc *)(tx_q->dma_etx + entry);
 | |
| 		else
 | |
| 			desc = tx_q->dma_tx + entry;
 | |
| 
 | |
| 		des2 = dma_map_single(priv->device, skb->data + bmax, len,
 | |
| 				      DMA_TO_DEVICE);
 | |
| 		desc->des2 = cpu_to_le32(des2);
 | |
| 		if (dma_mapping_error(priv->device, des2))
 | |
| 			return -1;
 | |
| 		tx_q->tx_skbuff_dma[entry].buf = des2;
 | |
| 		tx_q->tx_skbuff_dma[entry].len = len;
 | |
| 		tx_q->tx_skbuff_dma[entry].is_jumbo = true;
 | |
| 
 | |
| 		desc->des3 = cpu_to_le32(des2 + BUF_SIZE_4KiB);
 | |
| 		stmmac_prepare_tx_desc(priv, desc, 0, len, csum,
 | |
| 				STMMAC_RING_MODE, 1, !skb_is_nonlinear(skb),
 | |
| 				skb->len);
 | |
| 	} else {
 | |
| 		des2 = dma_map_single(priv->device, skb->data,
 | |
| 				      nopaged_len, DMA_TO_DEVICE);
 | |
| 		desc->des2 = cpu_to_le32(des2);
 | |
| 		if (dma_mapping_error(priv->device, des2))
 | |
| 			return -1;
 | |
| 		tx_q->tx_skbuff_dma[entry].buf = des2;
 | |
| 		tx_q->tx_skbuff_dma[entry].len = nopaged_len;
 | |
| 		tx_q->tx_skbuff_dma[entry].is_jumbo = true;
 | |
| 		desc->des3 = cpu_to_le32(des2 + BUF_SIZE_4KiB);
 | |
| 		stmmac_prepare_tx_desc(priv, desc, 1, nopaged_len, csum,
 | |
| 				STMMAC_RING_MODE, 0, !skb_is_nonlinear(skb),
 | |
| 				skb->len);
 | |
| 	}
 | |
| 
 | |
| 	tx_q->cur_tx = entry;
 | |
| 
 | |
| 	return entry;
 | |
| }
 | |
| 
 | |
| static unsigned int is_jumbo_frm(int len, int enh_desc)
 | |
| {
 | |
| 	unsigned int ret = 0;
 | |
| 
 | |
| 	if (len >= BUF_SIZE_4KiB)
 | |
| 		ret = 1;
 | |
| 
 | |
| 	return ret;
 | |
| }
 | |
| 
 | |
| static void refill_desc3(struct stmmac_rx_queue *rx_q, struct dma_desc *p)
 | |
| {
 | |
| 	struct stmmac_priv *priv = rx_q->priv_data;
 | |
| 
 | |
| 	/* Fill DES3 in case of RING mode */
 | |
| 	if (priv->dma_conf.dma_buf_sz == BUF_SIZE_16KiB)
 | |
| 		p->des3 = cpu_to_le32(le32_to_cpu(p->des2) + BUF_SIZE_8KiB);
 | |
| }
 | |
| 
 | |
| /* In ring mode we need to fill the desc3 because it is used as buffer */
 | |
| static void init_desc3(struct dma_desc *p)
 | |
| {
 | |
| 	p->des3 = cpu_to_le32(le32_to_cpu(p->des2) + BUF_SIZE_8KiB);
 | |
| }
 | |
| 
 | |
| static void clean_desc3(struct stmmac_tx_queue *tx_q, struct dma_desc *p)
 | |
| {
 | |
| 	struct stmmac_priv *priv = tx_q->priv_data;
 | |
| 	unsigned int entry = tx_q->dirty_tx;
 | |
| 
 | |
| 	/* des3 is only used for jumbo frames tx or time stamping */
 | |
| 	if (unlikely(tx_q->tx_skbuff_dma[entry].is_jumbo ||
 | |
| 		     (tx_q->tx_skbuff_dma[entry].last_segment &&
 | |
| 		      !priv->extend_desc && priv->hwts_tx_en)))
 | |
| 		p->des3 = 0;
 | |
| }
 | |
| 
 | |
| static int set_16kib_bfsize(int mtu)
 | |
| {
 | |
| 	int ret = 0;
 | |
| 	if (unlikely(mtu > BUF_SIZE_8KiB))
 | |
| 		ret = BUF_SIZE_16KiB;
 | |
| 	return ret;
 | |
| }
 | |
| 
 | |
| const struct stmmac_mode_ops ring_mode_ops = {
 | |
| 	.is_jumbo_frm = is_jumbo_frm,
 | |
| 	.jumbo_frm = jumbo_frm,
 | |
| 	.refill_desc3 = refill_desc3,
 | |
| 	.init_desc3 = init_desc3,
 | |
| 	.clean_desc3 = clean_desc3,
 | |
| 	.set_16kib_bfsize = set_16kib_bfsize,
 | |
| };
 |