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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/net/ethernet/stmicro/stmmac/chain_mode.c
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/net/ethernet/stmicro/stmmac/chain_mode.c')
-rw-r--r--drivers/net/ethernet/stmicro/stmmac/chain_mode.c168
1 files changed, 168 insertions, 0 deletions
diff --git a/drivers/net/ethernet/stmicro/stmmac/chain_mode.c b/drivers/net/ethernet/stmicro/stmmac/chain_mode.c
new file mode 100644
index 000000000..2e8744ac6
--- /dev/null
+++ b/drivers/net/ethernet/stmicro/stmmac/chain_mode.c
@@ -0,0 +1,168 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*******************************************************************************
+ Specialised functions for managing Chained 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, des2;
+ unsigned int i = 1, len;
+ struct dma_desc *desc;
+
+ desc = tx_q->dma_tx + entry;
+
+ if (priv->plat->enh_desc)
+ bmax = BUF_SIZE_8KiB;
+ else
+ bmax = BUF_SIZE_2KiB;
+
+ len = nopaged_len - bmax;
+
+ 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;
+ /* do not close the descriptor and do not set own bit */
+ stmmac_prepare_tx_desc(priv, desc, 1, bmax, csum, STMMAC_CHAIN_MODE,
+ 0, false, skb->len);
+
+ while (len != 0) {
+ tx_q->tx_skbuff[entry] = NULL;
+ entry = STMMAC_GET_ENTRY(entry, priv->dma_conf.dma_tx_size);
+ desc = tx_q->dma_tx + entry;
+
+ if (len > bmax) {
+ des2 = dma_map_single(priv->device,
+ (skb->data + bmax * i),
+ 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;
+ stmmac_prepare_tx_desc(priv, desc, 0, bmax, csum,
+ STMMAC_CHAIN_MODE, 1, false, skb->len);
+ len -= bmax;
+ i++;
+ } else {
+ des2 = dma_map_single(priv->device,
+ (skb->data + bmax * i), 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;
+ /* last descriptor can be set now */
+ stmmac_prepare_tx_desc(priv, desc, 0, len, csum,
+ STMMAC_CHAIN_MODE, 1, true, skb->len);
+ len = 0;
+ }
+ }
+
+ tx_q->cur_tx = entry;
+
+ return entry;
+}
+
+static unsigned int is_jumbo_frm(int len, int enh_desc)
+{
+ unsigned int ret = 0;
+
+ if ((enh_desc && (len > BUF_SIZE_8KiB)) ||
+ (!enh_desc && (len > BUF_SIZE_2KiB))) {
+ ret = 1;
+ }
+
+ return ret;
+}
+
+static void init_dma_chain(void *des, dma_addr_t phy_addr,
+ unsigned int size, unsigned int extend_desc)
+{
+ /*
+ * In chained mode the des3 points to the next element in the ring.
+ * The latest element has to point to the head.
+ */
+ int i;
+ dma_addr_t dma_phy = phy_addr;
+
+ if (extend_desc) {
+ struct dma_extended_desc *p = (struct dma_extended_desc *)des;
+ for (i = 0; i < (size - 1); i++) {
+ dma_phy += sizeof(struct dma_extended_desc);
+ p->basic.des3 = cpu_to_le32((unsigned int)dma_phy);
+ p++;
+ }
+ p->basic.des3 = cpu_to_le32((unsigned int)phy_addr);
+
+ } else {
+ struct dma_desc *p = (struct dma_desc *)des;
+ for (i = 0; i < (size - 1); i++) {
+ dma_phy += sizeof(struct dma_desc);
+ p->des3 = cpu_to_le32((unsigned int)dma_phy);
+ p++;
+ }
+ p->des3 = cpu_to_le32((unsigned int)phy_addr);
+ }
+}
+
+static void refill_desc3(void *priv_ptr, struct dma_desc *p)
+{
+ struct stmmac_rx_queue *rx_q = (struct stmmac_rx_queue *)priv_ptr;
+ struct stmmac_priv *priv = rx_q->priv_data;
+
+ if (priv->hwts_rx_en && !priv->extend_desc)
+ /* NOTE: Device will overwrite des3 with timestamp value if
+ * 1588-2002 time stamping is enabled, hence reinitialize it
+ * to keep explicit chaining in the descriptor.
+ */
+ p->des3 = cpu_to_le32((unsigned int)(rx_q->dma_rx_phy +
+ (((rx_q->dirty_rx) + 1) %
+ priv->dma_conf.dma_rx_size) *
+ sizeof(struct dma_desc)));
+}
+
+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;
+
+ if (tx_q->tx_skbuff_dma[entry].last_segment && !priv->extend_desc &&
+ priv->hwts_tx_en)
+ /* NOTE: Device will overwrite des3 with timestamp value if
+ * 1588-2002 time stamping is enabled, hence reinitialize it
+ * to keep explicit chaining in the descriptor.
+ */
+ p->des3 = cpu_to_le32((unsigned int)((tx_q->dma_tx_phy +
+ ((tx_q->dirty_tx + 1) %
+ priv->dma_conf.dma_tx_size))
+ * sizeof(struct dma_desc)));
+}
+
+const struct stmmac_mode_ops chain_mode_ops = {
+ .init = init_dma_chain,
+ .is_jumbo_frm = is_jumbo_frm,
+ .jumbo_frm = jumbo_frm,
+ .refill_desc3 = refill_desc3,
+ .clean_desc3 = clean_desc3,
+};