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Diffstat (limited to 'drivers/net/ethernet/stmicro/stmmac/ring_mode.c')
-rw-r--r--drivers/net/ethernet/stmicro/stmmac/ring_mode.c148
1 files changed, 148 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 000000000..8ad900949
--- /dev/null
+++ b/drivers/net/ethernet/stmicro/stmmac/ring_mode.c
@@ -0,0 +1,148 @@
+// 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(void *p, struct sk_buff *skb, int csum)
+{
+ struct stmmac_tx_queue *tx_q = (struct stmmac_tx_queue *)p;
+ 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_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(void *priv_ptr, struct dma_desc *p)
+{
+ struct stmmac_rx_queue *rx_q = priv_ptr;
+ struct stmmac_priv *priv = rx_q->priv_data;
+
+ /* Fill DES3 in case of RING mode */
+ if (priv->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(void *priv_ptr, struct dma_desc *p)
+{
+ struct stmmac_tx_queue *tx_q = (struct stmmac_tx_queue *)priv_ptr;
+ 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,
+};