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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
commit76cb841cb886eef6b3bee341a2266c76578724ad (patch)
treef5892e5ba6cc11949952a6ce4ecbe6d516d6ce58 /drivers/net/ethernet/stmicro/stmmac/chain_mode.c
parentInitial commit. (diff)
downloadlinux-76cb841cb886eef6b3bee341a2266c76578724ad.tar.xz
linux-76cb841cb886eef6b3bee341a2266c76578724ad.zip
Adding upstream version 4.19.249.upstream/4.19.249
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.c177
1 files changed, 177 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..b9c900306
--- /dev/null
+++ b/drivers/net/ethernet/stmicro/stmmac/chain_mode.c
@@ -0,0 +1,177 @@
+/*******************************************************************************
+ 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.
+
+ 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.
+
+ 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 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, 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) %
+ 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) % 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,
+};