@@ -11,5 +11,6 @@ mscc_ocelot_switch_lib-y := \
mscc_ocelot_switch_lib-$(CONFIG_BRIDGE_MRP) += ocelot_mrp.o
obj-$(CONFIG_MSCC_OCELOT_SWITCH) += mscc_ocelot.o
mscc_ocelot-y := \
+ ocelot_fdma.o \
ocelot_vsc7514.o \
ocelot_net.o
new file mode 100644
@@ -0,0 +1,894 @@
+// SPDX-License-Identifier: (GPL-2.0 OR MIT)
+/*
+ * Microsemi SoCs FDMA driver
+ *
+ * Copyright (c) 2021 Microchip
+ *
+ * Page recycling code is mostly taken from gianfar driver.
+ */
+
+#include <linux/align.h>
+#include <linux/bitops.h>
+#include <linux/dmapool.h>
+#include <linux/dsa/ocelot.h>
+#include <linux/netdevice.h>
+#include <linux/of_platform.h>
+#include <linux/skbuff.h>
+
+#include "ocelot_fdma.h"
+#include "ocelot_qs.h"
+
+DEFINE_STATIC_KEY_FALSE(ocelot_fdma_enabled);
+
+static void ocelot_fdma_writel(struct ocelot *ocelot, u32 reg, u32 data)
+{
+ regmap_write(ocelot->targets[FDMA], reg, data);
+}
+
+static u32 ocelot_fdma_readl(struct ocelot *ocelot, u32 reg)
+{
+ u32 retval;
+
+ regmap_read(ocelot->targets[FDMA], reg, &retval);
+
+ return retval;
+}
+
+static dma_addr_t ocelot_fdma_idx_dma(dma_addr_t base, u16 idx)
+{
+ return base + idx * sizeof(struct ocelot_fdma_dcb);
+}
+
+static u16 ocelot_fdma_dma_idx(dma_addr_t base, dma_addr_t dma)
+{
+ return (dma - base) / sizeof(struct ocelot_fdma_dcb);
+}
+
+static u16 ocelot_fdma_idx_next(u16 idx, u16 ring_sz)
+{
+ return unlikely(idx == ring_sz - 1) ? 0 : idx + 1;
+}
+
+static u16 ocelot_fdma_idx_prev(u16 idx, u16 ring_sz)
+{
+ return unlikely(idx == 0) ? ring_sz - 1 : idx - 1;
+}
+
+static int ocelot_fdma_rx_ring_free(struct ocelot_fdma *fdma)
+{
+ struct ocelot_fdma_rx_ring *rx_ring = &fdma->rx_ring;
+
+ if (rx_ring->next_to_use >= rx_ring->next_to_clean)
+ return OCELOT_FDMA_RX_RING_SIZE -
+ (rx_ring->next_to_use - rx_ring->next_to_clean) - 1;
+ else
+ return rx_ring->next_to_clean - rx_ring->next_to_use - 1;
+}
+
+static int ocelot_fdma_tx_ring_free(struct ocelot_fdma *fdma)
+{
+ struct ocelot_fdma_tx_ring *tx_ring = &fdma->tx_ring;
+
+ if (tx_ring->next_to_use >= tx_ring->next_to_clean)
+ return OCELOT_FDMA_TX_RING_SIZE -
+ (tx_ring->next_to_use - tx_ring->next_to_clean) - 1;
+ else
+ return tx_ring->next_to_clean - tx_ring->next_to_use - 1;
+}
+
+static bool ocelot_fdma_tx_ring_empty(struct ocelot_fdma *fdma)
+{
+ struct ocelot_fdma_tx_ring *tx_ring = &fdma->tx_ring;
+
+ return tx_ring->next_to_clean == tx_ring->next_to_use;
+}
+
+static void ocelot_fdma_activate_chan(struct ocelot *ocelot, dma_addr_t dma,
+ int chan)
+{
+ ocelot_fdma_writel(ocelot, MSCC_FDMA_DCB_LLP(chan), dma);
+ /* Barrier to force memory writes to DCB to be completed before starting
+ * the channel.
+ */
+ wmb();
+ ocelot_fdma_writel(ocelot, MSCC_FDMA_CH_ACTIVATE, BIT(chan));
+}
+
+static int ocelot_fdma_wait_chan_safe(struct ocelot *ocelot, int chan)
+{
+ unsigned long timeout;
+ u32 safe;
+
+ timeout = jiffies + usecs_to_jiffies(OCELOT_FDMA_CH_SAFE_TIMEOUT_US);
+ do {
+ safe = ocelot_fdma_readl(ocelot, MSCC_FDMA_CH_SAFE);
+ if (safe & BIT(chan))
+ return 0;
+ } while (time_after(jiffies, timeout));
+
+ return -ETIMEDOUT;
+}
+
+static void ocelot_fdma_dcb_set_data(struct ocelot_fdma_dcb *dcb,
+ dma_addr_t dma_addr,
+ size_t size)
+{
+ u32 offset = dma_addr & 0x3;
+
+ dcb->llp = 0;
+ dcb->datap = ALIGN_DOWN(dma_addr, 4);
+ dcb->datal = ALIGN_DOWN(size, 4);
+ dcb->stat = MSCC_FDMA_DCB_STAT_BLOCKO(offset);
+}
+
+static bool ocelot_fdma_rx_alloc_page(struct ocelot *ocelot,
+ struct ocelot_fdma_rx_buf *rxb)
+{
+ dma_addr_t mapping;
+ struct page *page;
+
+ page = dev_alloc_page();
+ if (unlikely(!page))
+ return false;
+
+ mapping = dma_map_page(ocelot->dev, page, 0, PAGE_SIZE,
+ DMA_FROM_DEVICE);
+ if (unlikely(dma_mapping_error(ocelot->dev, mapping))) {
+ __free_page(page);
+ return false;
+ }
+
+ rxb->page = page;
+ rxb->page_offset = 0;
+ rxb->dma_addr = mapping;
+
+ return true;
+}
+
+static int ocelot_fdma_alloc_rx_buffs(struct ocelot *ocelot, u16 alloc_cnt)
+{
+ struct ocelot_fdma *fdma = ocelot->fdma;
+ struct ocelot_fdma_rx_ring *rx_ring;
+ struct ocelot_fdma_rx_buf *rxb;
+ struct ocelot_fdma_dcb *dcb;
+ dma_addr_t dma_addr;
+ int ret = 0;
+ u16 idx;
+
+ rx_ring = &fdma->rx_ring;
+ idx = rx_ring->next_to_use;
+
+ while (alloc_cnt--) {
+ rxb = &rx_ring->bufs[idx];
+ /* try reuse page */
+ if (unlikely(!rxb->page)) {
+ if (unlikely(!ocelot_fdma_rx_alloc_page(ocelot, rxb))) {
+ dev_err_ratelimited(ocelot->dev,
+ "Failed to allocate rx\n");
+ ret = -ENOMEM;
+ break;
+ }
+ }
+
+ dcb = &rx_ring->dcbs[idx];
+ dma_addr = rxb->dma_addr + rxb->page_offset;
+ ocelot_fdma_dcb_set_data(dcb, dma_addr, OCELOT_FDMA_RXB_SIZE);
+
+ idx = ocelot_fdma_idx_next(idx, OCELOT_FDMA_RX_RING_SIZE);
+ /* Chain the DCB to the next one */
+ dcb->llp = ocelot_fdma_idx_dma(rx_ring->dcbs_dma, idx);
+ }
+
+ rx_ring->next_to_use = idx;
+ rx_ring->next_to_alloc = idx;
+
+ return ret;
+}
+
+static bool ocelot_fdma_tx_dcb_set_skb(struct ocelot *ocelot,
+ struct ocelot_fdma_tx_buf *tx_buf,
+ struct ocelot_fdma_dcb *dcb,
+ struct sk_buff *skb)
+{
+ dma_addr_t mapping;
+
+ mapping = dma_map_single(ocelot->dev, skb->data, skb->len,
+ DMA_TO_DEVICE);
+ if (unlikely(dma_mapping_error(ocelot->dev, mapping)))
+ return false;
+
+ dma_unmap_addr_set(tx_buf, dma_addr, mapping);
+
+ ocelot_fdma_dcb_set_data(dcb, mapping, OCELOT_FDMA_RX_SIZE);
+ tx_buf->skb = skb;
+ dcb->stat |= MSCC_FDMA_DCB_STAT_BLOCKL(skb->len);
+ dcb->stat |= MSCC_FDMA_DCB_STAT_SOF | MSCC_FDMA_DCB_STAT_EOF;
+
+ return true;
+}
+
+static bool ocelot_fdma_check_stop_rx(struct ocelot *ocelot)
+{
+ u32 llp;
+
+ /* Check if the FDMA hits the DCB with LLP == NULL */
+ llp = ocelot_fdma_readl(ocelot, MSCC_FDMA_DCB_LLP(MSCC_FDMA_XTR_CHAN));
+ if (unlikely(llp))
+ return false;
+
+ ocelot_fdma_writel(ocelot, MSCC_FDMA_CH_DISABLE,
+ BIT(MSCC_FDMA_XTR_CHAN));
+
+ return true;
+}
+
+static void ocelot_fdma_rx_set_llp(struct ocelot_fdma_rx_ring *rx_ring)
+{
+ struct ocelot_fdma_dcb *dcb;
+ unsigned int idx;
+
+ idx = ocelot_fdma_idx_prev(rx_ring->next_to_use,
+ OCELOT_FDMA_RX_RING_SIZE);
+ dcb = &rx_ring->dcbs[idx];
+ dcb->llp = 0;
+}
+
+static void ocelot_fdma_rx_restart(struct ocelot *ocelot)
+{
+ struct ocelot_fdma *fdma = ocelot->fdma;
+ struct ocelot_fdma_rx_ring *rx_ring;
+ const u8 chan = MSCC_FDMA_XTR_CHAN;
+ dma_addr_t new_llp, dma_base;
+ unsigned int idx;
+ u32 llp_prev;
+ int ret;
+
+ rx_ring = &fdma->rx_ring;
+ ret = ocelot_fdma_wait_chan_safe(ocelot, chan);
+ if (ret) {
+ dev_err_ratelimited(ocelot->dev,
+ "Unable to stop RX channel\n");
+ return;
+ }
+
+ ocelot_fdma_rx_set_llp(rx_ring);
+
+ /* FDMA stopped on the last DCB that contained a NULL LLP, since
+ * we processed some DCBs in RX, there is free space, and we must set
+ * DCB_LLP to point to the next DCB
+ */
+ llp_prev = ocelot_fdma_readl(ocelot, MSCC_FDMA_DCB_LLP_PREV(chan));
+ dma_base = rx_ring->dcbs_dma;
+
+ /* Get the next DMA addr located after LLP == NULL DCB */
+ idx = ocelot_fdma_dma_idx(dma_base, llp_prev);
+ idx = ocelot_fdma_idx_next(idx, OCELOT_FDMA_RX_RING_SIZE);
+ new_llp = ocelot_fdma_idx_dma(dma_base, idx);
+
+ /* Finally reactivate the channel */
+ ocelot_fdma_activate_chan(ocelot, new_llp, chan);
+}
+
+static bool ocelot_fdma_add_rx_frag(struct ocelot_fdma_rx_buf *rxb, u32 stat,
+ struct sk_buff *skb, bool first)
+{
+ int size = MSCC_FDMA_DCB_STAT_BLOCKL(stat);
+ struct page *page = rxb->page;
+
+ if (likely(first)) {
+ skb_put(skb, size);
+ } else {
+ skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags, page,
+ rxb->page_offset, size, OCELOT_FDMA_RX_SIZE);
+ }
+
+ /* Try to reuse page */
+ if (unlikely(page_ref_count(page) != 1 || page_is_pfmemalloc(page)))
+ return false;
+
+ /* Change offset to the other half */
+ rxb->page_offset ^= OCELOT_FDMA_RX_SIZE;
+
+ page_ref_inc(page);
+
+ return true;
+}
+
+static void ocelot_fdma_reuse_rx_page(struct ocelot *ocelot,
+ struct ocelot_fdma_rx_buf *old_rxb)
+{
+ struct ocelot_fdma_rx_ring *rx_ring = &ocelot->fdma->rx_ring;
+ struct ocelot_fdma_rx_buf *new_rxb;
+
+ new_rxb = &rx_ring->bufs[rx_ring->next_to_alloc];
+ rx_ring->next_to_alloc = ocelot_fdma_idx_next(rx_ring->next_to_alloc,
+ OCELOT_FDMA_RX_RING_SIZE);
+
+ /* Copy page reference */
+ *new_rxb = *old_rxb;
+
+ /* Sync for use by the device */
+ dma_sync_single_range_for_device(ocelot->dev, old_rxb->dma_addr,
+ old_rxb->page_offset,
+ OCELOT_FDMA_RX_SIZE, DMA_FROM_DEVICE);
+}
+
+static struct sk_buff *ocelot_fdma_get_skb(struct ocelot *ocelot, u32 stat,
+ struct ocelot_fdma_rx_buf *rxb,
+ struct sk_buff *skb)
+{
+ bool first = false;
+
+ /* Allocate skb head and data */
+ if (likely(!skb)) {
+ void *buff_addr = page_address(rxb->page) +
+ rxb->page_offset;
+
+ skb = build_skb(buff_addr, OCELOT_FDMA_SKBFRAG_SIZE);
+ if (unlikely(!skb)) {
+ dev_err_ratelimited(ocelot->dev,
+ "build_skb failed !\n");
+ return NULL;
+ }
+ first = true;
+ }
+
+ dma_sync_single_range_for_cpu(ocelot->dev, rxb->dma_addr,
+ rxb->page_offset, OCELOT_FDMA_RX_SIZE,
+ DMA_FROM_DEVICE);
+
+ if (ocelot_fdma_add_rx_frag(rxb, stat, skb, first)) {
+ /* Reuse the free half of the page for the next_to_alloc DCB*/
+ ocelot_fdma_reuse_rx_page(ocelot, rxb);
+ } else {
+ /* page cannot be reused, unmap it */
+ dma_unmap_page(ocelot->dev, rxb->dma_addr, PAGE_SIZE,
+ DMA_FROM_DEVICE);
+ }
+
+ /* clear rx buff content */
+ rxb->page = NULL;
+
+ return skb;
+}
+
+static bool ocelot_fdma_receive_skb(struct ocelot *ocelot, struct sk_buff *skb)
+{
+ struct net_device *ndev;
+ void *xfh = skb->data;
+ u64 timestamp;
+ u64 src_port;
+
+ skb_pull(skb, OCELOT_TAG_LEN);
+
+ ocelot_xfh_get_src_port(xfh, &src_port);
+ if (unlikely(src_port >= ocelot->num_phys_ports))
+ return false;
+
+ ndev = ocelot_port_to_netdev(ocelot, src_port);
+ if (unlikely(!ndev))
+ return false;
+
+ pskb_trim(skb, skb->len - ETH_FCS_LEN);
+
+ skb->dev = ndev;
+ skb->protocol = eth_type_trans(skb, skb->dev);
+ skb->dev->stats.rx_bytes += skb->len;
+ skb->dev->stats.rx_packets++;
+
+ if (ocelot->ptp) {
+ ocelot_xfh_get_rew_val(xfh, ×tamp);
+ ocelot_ptp_rx_timestamp(ocelot, skb, timestamp);
+ }
+
+ if (likely(!skb_defer_rx_timestamp(skb)))
+ netif_receive_skb(skb);
+
+ return true;
+}
+
+static int ocelot_fdma_rx_get(struct ocelot *ocelot, int budget)
+{
+ struct ocelot_fdma *fdma = ocelot->fdma;
+ struct ocelot_fdma_rx_ring *rx_ring;
+ struct ocelot_fdma_rx_buf *rxb;
+ struct ocelot_fdma_dcb *dcb;
+ struct sk_buff *skb;
+ int work_done = 0;
+ int cleaned_cnt;
+ u32 stat;
+ u16 idx;
+
+ cleaned_cnt = ocelot_fdma_rx_ring_free(fdma);
+ rx_ring = &fdma->rx_ring;
+ skb = rx_ring->skb;
+
+ while (budget--) {
+ idx = rx_ring->next_to_clean;
+ dcb = &rx_ring->dcbs[idx];
+ stat = dcb->stat;
+ if (MSCC_FDMA_DCB_STAT_BLOCKL(stat) == 0)
+ break;
+
+ /* New packet is a start of frame but we already got a skb set,
+ * we probably lost an EOF packet, free skb
+ */
+ if (unlikely(skb && (stat & MSCC_FDMA_DCB_STAT_SOF))) {
+ dev_kfree_skb(skb);
+ skb = NULL;
+ }
+
+ rxb = &rx_ring->bufs[idx];
+ /* Fetch next to clean buffer from the rx_ring */
+ skb = ocelot_fdma_get_skb(ocelot, stat, rxb, skb);
+ if (unlikely(!skb))
+ break;
+
+ work_done++;
+ cleaned_cnt++;
+
+ idx = ocelot_fdma_idx_next(idx, OCELOT_FDMA_RX_RING_SIZE);
+ rx_ring->next_to_clean = idx;
+
+ if (unlikely(stat & MSCC_FDMA_DCB_STAT_ABORT ||
+ stat & MSCC_FDMA_DCB_STAT_PD)) {
+ dev_err_ratelimited(ocelot->dev,
+ "DCB aborted or pruned\n");
+ dev_kfree_skb(skb);
+ skb = NULL;
+ continue;
+ }
+
+ /* We still need to process the other fragment of the packet
+ * before delivering it to the network stack
+ */
+ if (!(stat & MSCC_FDMA_DCB_STAT_EOF))
+ continue;
+
+ if (unlikely(!ocelot_fdma_receive_skb(ocelot, skb)))
+ dev_kfree_skb(skb);
+
+ skb = NULL;
+ }
+
+ rx_ring->skb = skb;
+
+ if (cleaned_cnt)
+ ocelot_fdma_alloc_rx_buffs(ocelot, cleaned_cnt);
+
+ return work_done;
+}
+
+static void ocelot_fdma_wakeup_netdev(struct ocelot *ocelot)
+{
+ struct ocelot_port_private *priv;
+ struct ocelot_port *ocelot_port;
+ struct net_device *dev;
+ int port;
+
+ for (port = 0; port < ocelot->num_phys_ports; port++) {
+ ocelot_port = ocelot->ports[port];
+ if (!ocelot_port)
+ continue;
+ priv = container_of(ocelot_port, struct ocelot_port_private,
+ port);
+ dev = priv->dev;
+
+ if (unlikely(netif_queue_stopped(dev)))
+ netif_wake_queue(dev);
+ }
+}
+
+static void ocelot_fdma_tx_cleanup(struct ocelot *ocelot, int budget)
+{
+ struct ocelot_fdma *fdma = ocelot->fdma;
+ struct ocelot_fdma_tx_ring *tx_ring;
+ struct ocelot_fdma_tx_buf *buf;
+ unsigned int new_null_llp_idx;
+ struct ocelot_fdma_dcb *dcb;
+ bool end_of_list = false;
+ struct sk_buff *skb;
+ dma_addr_t dma;
+ u32 dcb_llp;
+ u16 ntc;
+ int ret;
+
+ tx_ring = &fdma->tx_ring;
+
+ /* Purge the TX packets that have been sent up to the NULL llp or the
+ * end of done list.
+ */
+ while (!ocelot_fdma_tx_ring_empty(fdma)) {
+ ntc = tx_ring->next_to_clean;
+ dcb = &tx_ring->dcbs[ntc];
+ if (!(dcb->stat & MSCC_FDMA_DCB_STAT_PD))
+ break;
+
+ buf = &tx_ring->bufs[ntc];
+ skb = buf->skb;
+ dma_unmap_single(ocelot->dev, dma_unmap_addr(buf, dma_addr),
+ skb->len, DMA_TO_DEVICE);
+ napi_consume_skb(skb, budget);
+ dcb_llp = dcb->llp;
+
+ /* Only update after accessing all dcb fields */
+ tx_ring->next_to_clean = ocelot_fdma_idx_next(ntc,
+ OCELOT_FDMA_TX_RING_SIZE);
+
+ /* If we hit the NULL LLP, stop, we might need to reload FDMA */
+ if (dcb_llp == 0) {
+ end_of_list = true;
+ break;
+ }
+ }
+
+ /* No need to try to wake if there were no TX cleaned_cnt up. */
+ if (ocelot_fdma_tx_ring_free(fdma))
+ ocelot_fdma_wakeup_netdev(ocelot);
+
+ /* If there is still some DCBs to be processed by the FDMA or if the
+ * pending list is empty, there is no need to restart the FDMA.
+ */
+ if (!end_of_list || ocelot_fdma_tx_ring_empty(fdma))
+ return;
+
+ ret = ocelot_fdma_wait_chan_safe(ocelot, MSCC_FDMA_INJ_CHAN);
+ if (ret) {
+ dev_warn(ocelot->dev,
+ "Failed to wait for TX channel to stop\n");
+ return;
+ }
+
+ /* Set NULL LLP to be the last DCB used */
+ new_null_llp_idx = ocelot_fdma_idx_prev(tx_ring->next_to_use,
+ OCELOT_FDMA_TX_RING_SIZE);
+ dcb = &tx_ring->dcbs[new_null_llp_idx];
+ dcb->llp = 0;
+
+ dma = ocelot_fdma_idx_dma(tx_ring->dcbs_dma, tx_ring->next_to_clean);
+ ocelot_fdma_activate_chan(ocelot, dma, MSCC_FDMA_INJ_CHAN);
+}
+
+static int ocelot_fdma_napi_poll(struct napi_struct *napi, int budget)
+{
+ struct ocelot_fdma *fdma = container_of(napi, struct ocelot_fdma, napi);
+ struct ocelot *ocelot = fdma->ocelot;
+ int work_done = 0;
+ bool rx_stopped;
+
+ ocelot_fdma_tx_cleanup(ocelot, budget);
+
+ rx_stopped = ocelot_fdma_check_stop_rx(ocelot);
+
+ work_done = ocelot_fdma_rx_get(ocelot, budget);
+
+ if (rx_stopped)
+ ocelot_fdma_rx_restart(ocelot);
+
+ if (work_done < budget) {
+ napi_complete_done(&fdma->napi, work_done);
+ ocelot_fdma_writel(ocelot, MSCC_FDMA_INTR_ENA,
+ BIT(MSCC_FDMA_INJ_CHAN) |
+ BIT(MSCC_FDMA_XTR_CHAN));
+ }
+
+ return work_done;
+}
+
+static irqreturn_t ocelot_fdma_interrupt(int irq, void *dev_id)
+{
+ u32 ident, llp, frm, err, err_code;
+ struct ocelot *ocelot = dev_id;
+
+ ident = ocelot_fdma_readl(ocelot, MSCC_FDMA_INTR_IDENT);
+ frm = ocelot_fdma_readl(ocelot, MSCC_FDMA_INTR_FRM);
+ llp = ocelot_fdma_readl(ocelot, MSCC_FDMA_INTR_LLP);
+
+ ocelot_fdma_writel(ocelot, MSCC_FDMA_INTR_LLP, llp & ident);
+ ocelot_fdma_writel(ocelot, MSCC_FDMA_INTR_FRM, frm & ident);
+ if (frm || llp) {
+ ocelot_fdma_writel(ocelot, MSCC_FDMA_INTR_ENA, 0);
+ napi_schedule(&ocelot->fdma->napi);
+ }
+
+ err = ocelot_fdma_readl(ocelot, MSCC_FDMA_EVT_ERR);
+ if (unlikely(err)) {
+ err_code = ocelot_fdma_readl(ocelot, MSCC_FDMA_EVT_ERR_CODE);
+ dev_err_ratelimited(ocelot->dev,
+ "Error ! chans mask: %#x, code: %#x\n",
+ err, err_code);
+
+ ocelot_fdma_writel(ocelot, MSCC_FDMA_EVT_ERR, err);
+ ocelot_fdma_writel(ocelot, MSCC_FDMA_EVT_ERR_CODE, err_code);
+ }
+
+ return IRQ_HANDLED;
+}
+
+static void ocelot_fdma_send_skb(struct ocelot *ocelot,
+ struct ocelot_fdma *fdma, struct sk_buff *skb)
+{
+ struct ocelot_fdma_tx_ring *tx_ring = &fdma->tx_ring;
+ struct ocelot_fdma_tx_buf *tx_buf;
+ struct ocelot_fdma_dcb *dcb;
+ dma_addr_t dma;
+ u16 next_idx;
+
+ dcb = &tx_ring->dcbs[tx_ring->next_to_use];
+ tx_buf = &tx_ring->bufs[tx_ring->next_to_use];
+ if (!ocelot_fdma_tx_dcb_set_skb(ocelot, tx_buf, dcb, skb)) {
+ dev_kfree_skb_any(skb);
+ return;
+ }
+
+ next_idx = ocelot_fdma_idx_next(tx_ring->next_to_use,
+ OCELOT_FDMA_TX_RING_SIZE);
+ skb_tx_timestamp(skb);
+
+ /* If the FDMA TX chan is empty, then enqueue the DCB directly */
+ if (ocelot_fdma_tx_ring_empty(fdma)) {
+ dma = ocelot_fdma_idx_dma(tx_ring->dcbs_dma,
+ tx_ring->next_to_use);
+ ocelot_fdma_activate_chan(ocelot, dma, MSCC_FDMA_INJ_CHAN);
+ } else {
+ /* Chain the DCBs */
+ dcb->llp = ocelot_fdma_idx_dma(tx_ring->dcbs_dma, next_idx);
+ }
+
+ tx_ring->next_to_use = next_idx;
+}
+
+static int ocelot_fdma_prepare_skb(struct ocelot *ocelot, int port, u32 rew_op,
+ struct sk_buff *skb, struct net_device *dev)
+{
+ int needed_headroom = max_t(int, OCELOT_TAG_LEN - skb_headroom(skb), 0);
+ int needed_tailroom = max_t(int, ETH_FCS_LEN - skb_tailroom(skb), 0);
+ void *ifh;
+ int err;
+
+ if (unlikely(needed_headroom || needed_tailroom ||
+ skb_header_cloned(skb))) {
+ err = pskb_expand_head(skb, needed_headroom, needed_tailroom,
+ GFP_ATOMIC);
+ if (unlikely(err)) {
+ dev_kfree_skb_any(skb);
+ return 1;
+ }
+ }
+
+ err = skb_linearize(skb);
+ if (err) {
+ net_err_ratelimited("%s: skb_linearize error (%d)!\n",
+ dev->name, err);
+ dev_kfree_skb_any(skb);
+ return 1;
+ }
+
+ ifh = skb_push(skb, OCELOT_TAG_LEN);
+ skb_put(skb, ETH_FCS_LEN);
+ memset(ifh, 0, OCELOT_TAG_LEN);
+ ocelot_ifh_port_set(ifh, port, rew_op, skb_vlan_tag_get(skb));
+
+ return 0;
+}
+
+int ocelot_fdma_inject_frame(struct ocelot *ocelot, int port, u32 rew_op,
+ struct sk_buff *skb, struct net_device *dev)
+{
+ struct ocelot_fdma *fdma = ocelot->fdma;
+ int ret = NETDEV_TX_OK;
+
+ spin_lock(&fdma->tx_ring.xmit_lock);
+
+ if (ocelot_fdma_tx_ring_free(fdma) == 0) {
+ netif_stop_queue(dev);
+ ret = NETDEV_TX_BUSY;
+ goto out;
+ }
+
+ if (ocelot_fdma_prepare_skb(ocelot, port, rew_op, skb, dev))
+ goto out;
+
+ ocelot_fdma_send_skb(ocelot, fdma, skb);
+
+out:
+ spin_unlock(&fdma->tx_ring.xmit_lock);
+
+ return ret;
+}
+
+static void ocelot_fdma_free_rx_ring(struct ocelot *ocelot)
+{
+ struct ocelot_fdma *fdma = ocelot->fdma;
+ struct ocelot_fdma_rx_ring *rx_ring;
+ struct ocelot_fdma_rx_buf *rxb;
+ u16 idx;
+
+ rx_ring = &fdma->rx_ring;
+ idx = rx_ring->next_to_clean;
+
+ /* Free the pages held in the RX ring */
+ while (idx != rx_ring->next_to_use) {
+ rxb = &rx_ring->bufs[idx];
+ dma_unmap_page(ocelot->dev, rxb->dma_addr, PAGE_SIZE,
+ DMA_FROM_DEVICE);
+ __free_page(rxb->page);
+ idx = ocelot_fdma_idx_next(idx, OCELOT_FDMA_RX_RING_SIZE);
+ }
+
+ if (fdma->rx_ring.skb)
+ dev_kfree_skb_any(fdma->rx_ring.skb);
+}
+
+static void ocelot_fdma_free_tx_ring(struct ocelot *ocelot)
+{
+ struct ocelot_fdma *fdma = ocelot->fdma;
+ struct ocelot_fdma_tx_ring *tx_ring;
+ struct ocelot_fdma_tx_buf *txb;
+ struct sk_buff *skb;
+ u16 idx;
+
+ tx_ring = &fdma->tx_ring;
+ idx = tx_ring->next_to_clean;
+
+ while (idx != tx_ring->next_to_use) {
+ txb = &tx_ring->bufs[idx];
+ skb = txb->skb;
+ dma_unmap_single(ocelot->dev, txb->dma_addr, skb->len,
+ DMA_TO_DEVICE);
+ dev_kfree_skb_any(skb);
+ idx = ocelot_fdma_idx_next(idx, OCELOT_FDMA_TX_RING_SIZE);
+ }
+}
+
+static int ocelot_fdma_rings_alloc(struct ocelot *ocelot)
+{
+ struct ocelot_fdma *fdma = ocelot->fdma;
+ struct ocelot_fdma_dcb *dcbs;
+ unsigned int adjust;
+ dma_addr_t dcbs_dma;
+ int ret;
+
+ /* Create a pool of consistent memory blocks for hardware descriptors */
+ fdma->dcbs_base = dmam_alloc_coherent(ocelot->dev,
+ OCELOT_DCBS_HW_ALLOC_SIZE,
+ &fdma->dcbs_dma_base, GFP_KERNEL);
+ if (!fdma->dcbs_base)
+ return -ENOMEM;
+
+ /* DCBs must be aligned on a 32bit boundary */
+ dcbs = fdma->dcbs_base;
+ dcbs_dma = fdma->dcbs_dma_base;
+ if (!IS_ALIGNED(dcbs_dma, 4)) {
+ adjust = dcbs_dma & 0x3;
+ dcbs_dma = ALIGN(dcbs_dma, 4);
+ dcbs = (void *)dcbs + adjust;
+ }
+
+ /* TX queue */
+ fdma->tx_ring.dcbs = dcbs;
+ fdma->tx_ring.dcbs_dma = dcbs_dma;
+ spin_lock_init(&fdma->tx_ring.xmit_lock);
+
+ /* RX queue */
+ fdma->rx_ring.dcbs = dcbs + OCELOT_FDMA_TX_RING_SIZE;
+ fdma->rx_ring.dcbs_dma = dcbs_dma + OCELOT_FDMA_TX_DCB_SIZE;
+ ret = ocelot_fdma_alloc_rx_buffs(ocelot,
+ ocelot_fdma_tx_ring_free(fdma));
+ if (ret) {
+ ocelot_fdma_free_rx_ring(ocelot);
+ return ret;
+ }
+
+ /* Set the last DCB LLP as NULL, this is normally done when restarting
+ * the RX chan, but this is for the first run
+ */
+ ocelot_fdma_rx_set_llp(&fdma->rx_ring);
+
+ return 0;
+}
+
+void ocelot_fdma_netdev_init(struct ocelot *ocelot, struct net_device *dev)
+{
+ struct ocelot_fdma *fdma = ocelot->fdma;
+
+ dev->needed_headroom = OCELOT_TAG_LEN;
+ dev->needed_tailroom = ETH_FCS_LEN;
+
+ if (fdma->ndev)
+ return;
+
+ fdma->ndev = dev;
+ netif_napi_add(dev, &fdma->napi, ocelot_fdma_napi_poll,
+ OCELOT_FDMA_WEIGHT);
+}
+
+void ocelot_fdma_netdev_deinit(struct ocelot *ocelot, struct net_device *dev)
+{
+ struct ocelot_fdma *fdma = ocelot->fdma;
+
+ if (fdma->ndev == dev) {
+ netif_napi_del(&fdma->napi);
+ fdma->ndev = NULL;
+ }
+}
+
+void ocelot_fdma_init(struct platform_device *pdev, struct ocelot *ocelot)
+{
+ struct device *dev = ocelot->dev;
+ struct ocelot_fdma *fdma;
+ int ret;
+
+ fdma = devm_kzalloc(dev, sizeof(*fdma), GFP_KERNEL);
+ if (!fdma)
+ return;
+
+ ocelot->fdma = fdma;
+ ocelot->dev->coherent_dma_mask = DMA_BIT_MASK(32);
+
+ ocelot_fdma_writel(ocelot, MSCC_FDMA_INTR_ENA, 0);
+
+ fdma->ocelot = ocelot;
+ fdma->irq = platform_get_irq_byname(pdev, "fdma");
+ ret = devm_request_irq(dev, fdma->irq, ocelot_fdma_interrupt, 0,
+ dev_name(dev), ocelot);
+ if (ret)
+ goto err_free_fdma;
+
+ ret = ocelot_fdma_rings_alloc(ocelot);
+ if (ret)
+ goto err_free_irq;
+
+ static_branch_enable(&ocelot_fdma_enabled);
+
+ return;
+
+err_free_irq:
+ devm_free_irq(dev, fdma->irq, fdma);
+err_free_fdma:
+ devm_kfree(dev, fdma);
+
+ ocelot->fdma = NULL;
+}
+
+void ocelot_fdma_start(struct ocelot *ocelot)
+{
+ struct ocelot_fdma *fdma = ocelot->fdma;
+
+ /* Reconfigure for extraction and injection using DMA */
+ ocelot_write_rix(ocelot, QS_INJ_GRP_CFG_MODE(2), QS_INJ_GRP_CFG, 0);
+ ocelot_write_rix(ocelot, QS_INJ_CTRL_GAP_SIZE(0), QS_INJ_CTRL, 0);
+
+ ocelot_write_rix(ocelot, QS_XTR_GRP_CFG_MODE(2), QS_XTR_GRP_CFG, 0);
+
+ ocelot_fdma_writel(ocelot, MSCC_FDMA_INTR_LLP, 0xffffffff);
+ ocelot_fdma_writel(ocelot, MSCC_FDMA_INTR_FRM, 0xffffffff);
+
+ ocelot_fdma_writel(ocelot, MSCC_FDMA_INTR_LLP_ENA,
+ BIT(MSCC_FDMA_INJ_CHAN) | BIT(MSCC_FDMA_XTR_CHAN));
+ ocelot_fdma_writel(ocelot, MSCC_FDMA_INTR_FRM_ENA,
+ BIT(MSCC_FDMA_XTR_CHAN));
+ ocelot_fdma_writel(ocelot, MSCC_FDMA_INTR_ENA,
+ BIT(MSCC_FDMA_INJ_CHAN) | BIT(MSCC_FDMA_XTR_CHAN));
+
+ napi_enable(&fdma->napi);
+
+ ocelot_fdma_activate_chan(ocelot, ocelot->fdma->rx_ring.dcbs_dma,
+ MSCC_FDMA_XTR_CHAN);
+}
+
+void ocelot_fdma_deinit(struct ocelot *ocelot)
+{
+ struct ocelot_fdma *fdma = ocelot->fdma;
+
+ ocelot_fdma_writel(ocelot, MSCC_FDMA_INTR_ENA, 0);
+ ocelot_fdma_writel(ocelot, MSCC_FDMA_CH_FORCEDIS,
+ BIT(MSCC_FDMA_XTR_CHAN));
+ ocelot_fdma_writel(ocelot, MSCC_FDMA_CH_FORCEDIS,
+ BIT(MSCC_FDMA_INJ_CHAN));
+ napi_synchronize(&fdma->napi);
+ napi_disable(&fdma->napi);
+
+ ocelot_fdma_free_rx_ring(ocelot);
+ ocelot_fdma_free_tx_ring(ocelot);
+}
new file mode 100644
@@ -0,0 +1,166 @@
+/* SPDX-License-Identifier: (GPL-2.0 OR MIT) */
+/*
+ * Microsemi SoCs FDMA driver
+ *
+ * Copyright (c) 2021 Microchip
+ */
+#ifndef _MSCC_OCELOT_FDMA_H_
+#define _MSCC_OCELOT_FDMA_H_
+
+#include "ocelot.h"
+
+#define MSCC_FDMA_DCB_STAT_BLOCKO(x) (((x) << 20) & GENMASK(31, 20))
+#define MSCC_FDMA_DCB_STAT_BLOCKO_M GENMASK(31, 20)
+#define MSCC_FDMA_DCB_STAT_BLOCKO_X(x) (((x) & GENMASK(31, 20)) >> 20)
+#define MSCC_FDMA_DCB_STAT_PD BIT(19)
+#define MSCC_FDMA_DCB_STAT_ABORT BIT(18)
+#define MSCC_FDMA_DCB_STAT_EOF BIT(17)
+#define MSCC_FDMA_DCB_STAT_SOF BIT(16)
+#define MSCC_FDMA_DCB_STAT_BLOCKL_M GENMASK(15, 0)
+#define MSCC_FDMA_DCB_STAT_BLOCKL(x) ((x) & GENMASK(15, 0))
+
+#define MSCC_FDMA_DCB_LLP(x) ((x) * 4 + 0x0)
+#define MSCC_FDMA_DCB_LLP_PREV(x) ((x) * 4 + 0xA0)
+#define MSCC_FDMA_CH_SAFE 0xcc
+#define MSCC_FDMA_CH_ACTIVATE 0xd0
+#define MSCC_FDMA_CH_DISABLE 0xd4
+#define MSCC_FDMA_CH_FORCEDIS 0xd8
+#define MSCC_FDMA_EVT_ERR 0x164
+#define MSCC_FDMA_EVT_ERR_CODE 0x168
+#define MSCC_FDMA_INTR_LLP 0x16c
+#define MSCC_FDMA_INTR_LLP_ENA 0x170
+#define MSCC_FDMA_INTR_FRM 0x174
+#define MSCC_FDMA_INTR_FRM_ENA 0x178
+#define MSCC_FDMA_INTR_ENA 0x184
+#define MSCC_FDMA_INTR_IDENT 0x188
+
+#define MSCC_FDMA_INJ_CHAN 2
+#define MSCC_FDMA_XTR_CHAN 0
+
+#define OCELOT_FDMA_WEIGHT 32
+
+#define OCELOT_FDMA_CH_SAFE_TIMEOUT_US 10
+
+#define OCELOT_FDMA_RX_RING_SIZE 512
+#define OCELOT_FDMA_TX_RING_SIZE 128
+
+#define OCELOT_FDMA_RX_DCB_SIZE (OCELOT_FDMA_RX_RING_SIZE * \
+ sizeof(struct ocelot_fdma_dcb))
+#define OCELOT_FDMA_TX_DCB_SIZE (OCELOT_FDMA_TX_RING_SIZE * \
+ sizeof(struct ocelot_fdma_dcb))
+/* +4 allows for word alignment after allocation */
+#define OCELOT_DCBS_HW_ALLOC_SIZE (OCELOT_FDMA_RX_DCB_SIZE + \
+ OCELOT_FDMA_TX_DCB_SIZE + \
+ 4)
+
+#define OCELOT_FDMA_RX_SIZE (PAGE_SIZE / 2)
+
+#define OCELOT_FDMA_SKBFRAG_OVR (4 + SKB_DATA_ALIGN(sizeof(struct skb_shared_info)))
+#define OCELOT_FDMA_RXB_SIZE ALIGN_DOWN(OCELOT_FDMA_RX_SIZE - OCELOT_FDMA_SKBFRAG_OVR, 4)
+#define OCELOT_FDMA_SKBFRAG_SIZE (OCELOT_FDMA_RXB_SIZE + OCELOT_FDMA_SKBFRAG_OVR)
+
+DECLARE_STATIC_KEY_FALSE(ocelot_fdma_enabled);
+
+struct ocelot_fdma_dcb {
+ u32 llp;
+ u32 datap;
+ u32 datal;
+ u32 stat;
+} __packed;
+
+/**
+ * struct ocelot_fdma_tx_buf - TX buffer structure
+ * @skb: SKB currently used in the corresponding DCB.
+ * @dma_addr: SKB DMA mapped address.
+ */
+struct ocelot_fdma_tx_buf {
+ struct sk_buff *skb;
+ DEFINE_DMA_UNMAP_ADDR(dma_addr);
+};
+
+/**
+ * struct ocelot_fdma_tx_ring - TX ring description of DCBs
+ *
+ * @dcbs: DCBs allocated for the ring
+ * @dcbs_dma: DMA base address of the DCBs
+ * @bufs: List of TX buffer associated to the DCBs
+ * @xmit_lock: lock for concurrent xmit access
+ * @next_to_clean: Next DCB to be cleaned in tx_cleanup
+ * @next_to_use: Next available DCB to send SKB
+ */
+struct ocelot_fdma_tx_ring {
+ struct ocelot_fdma_dcb *dcbs;
+ dma_addr_t dcbs_dma;
+ struct ocelot_fdma_tx_buf bufs[OCELOT_FDMA_TX_RING_SIZE];
+ /* Protect concurrent xmit calls */
+ spinlock_t xmit_lock;
+ u16 next_to_clean;
+ u16 next_to_use;
+};
+
+/**
+ * struct ocelot_fdma_rx_buf - RX buffer structure
+ * @page: Struct page used in this buffer
+ * @page_offset: Current page offset (either 0 or PAGE_SIZE/2)
+ * @dma_addr: DMA address of the page
+ */
+struct ocelot_fdma_rx_buf {
+ struct page *page;
+ u32 page_offset;
+ dma_addr_t dma_addr;
+};
+
+/**
+ * struct ocelot_fdma_rx_ring - TX ring description of DCBs
+ *
+ * @dcbs: DCBs allocated for the ring
+ * @dcbs_dma: DMA base address of the DCBs
+ * @bufs: List of RX buffer associated to the DCBs
+ * @skb: SKB currently received by the netdev
+ * @next_to_clean: Next DCB to be cleaned NAPI polling
+ * @next_to_use: Next available DCB to send SKB
+ * @next_to_alloc: Next buffer that needs to be allocated (page reuse or alloc)
+ */
+struct ocelot_fdma_rx_ring {
+ struct ocelot_fdma_dcb *dcbs;
+ dma_addr_t dcbs_dma;
+ struct ocelot_fdma_rx_buf bufs[OCELOT_FDMA_RX_RING_SIZE];
+ struct sk_buff *skb;
+ u16 next_to_clean;
+ u16 next_to_use;
+ u16 next_to_alloc;
+};
+
+/**
+ * struct ocelot_fdma - FDMA context
+ *
+ * @irq: FDMA interrupt
+ * @ndev: Net device used to initialize NAPI
+ * @dcbs_base: Memory coherent DCBs
+ * @dcbs_dma_base: DMA base address of memory coherent DCBs
+ * @tx_ring: Injection ring
+ * @rx_ring: Extraction ring
+ * @napi: NAPI context
+ * @ocelot: Back-pointer to ocelot struct
+ */
+struct ocelot_fdma {
+ int irq;
+ struct net_device *ndev;
+ struct ocelot_fdma_dcb *dcbs_base;
+ dma_addr_t dcbs_dma_base;
+ struct ocelot_fdma_tx_ring tx_ring;
+ struct ocelot_fdma_rx_ring rx_ring;
+ struct napi_struct napi;
+ struct ocelot *ocelot;
+};
+
+void ocelot_fdma_init(struct platform_device *pdev, struct ocelot *ocelot);
+void ocelot_fdma_start(struct ocelot *ocelot);
+void ocelot_fdma_deinit(struct ocelot *ocelot);
+int ocelot_fdma_inject_frame(struct ocelot *fdma, int port, u32 rew_op,
+ struct sk_buff *skb, struct net_device *dev);
+void ocelot_fdma_netdev_init(struct ocelot *ocelot, struct net_device *dev);
+void ocelot_fdma_netdev_deinit(struct ocelot *ocelot,
+ struct net_device *dev);
+
+#endif
@@ -15,6 +15,7 @@
#include <net/pkt_cls.h>
#include "ocelot.h"
#include "ocelot_vcap.h"
+#include "ocelot_fdma.h"
#define OCELOT_MAC_QUIRKS OCELOT_QUIRK_QSGMII_PORTS_MUST_BE_UP
@@ -457,7 +458,8 @@ static netdev_tx_t ocelot_port_xmit(struct sk_buff *skb, struct net_device *dev)
int port = priv->chip_port;
u32 rew_op = 0;
- if (!ocelot_can_inject(ocelot, 0))
+ if (!static_branch_unlikely(&ocelot_fdma_enabled) &&
+ !ocelot_can_inject(ocelot, 0))
return NETDEV_TX_BUSY;
/* Check if timestamping is needed */
@@ -475,9 +477,13 @@ static netdev_tx_t ocelot_port_xmit(struct sk_buff *skb, struct net_device *dev)
rew_op = ocelot_ptp_rew_op(skb);
}
- ocelot_port_inject_frame(ocelot, port, 0, rew_op, skb);
+ if (static_branch_unlikely(&ocelot_fdma_enabled)) {
+ ocelot_fdma_inject_frame(ocelot, port, rew_op, skb, dev);
+ } else {
+ ocelot_port_inject_frame(ocelot, port, 0, rew_op, skb);
- kfree_skb(skb);
+ consume_skb(skb);
+ }
return NETDEV_TX_OK;
}
@@ -1702,14 +1708,20 @@ int ocelot_probe_port(struct ocelot *ocelot, int port, struct regmap *target,
if (err)
goto out;
+ if (ocelot->fdma)
+ ocelot_fdma_netdev_init(ocelot, dev);
+
err = register_netdev(dev);
if (err) {
dev_err(ocelot->dev, "register_netdev failed\n");
- goto out;
+ goto out_fdma_deinit;
}
return 0;
+out_fdma_deinit:
+ if (ocelot->fdma)
+ ocelot_fdma_netdev_deinit(ocelot, dev);
out:
ocelot->ports[port] = NULL;
free_netdev(dev);
@@ -1722,9 +1734,14 @@ void ocelot_release_port(struct ocelot_port *ocelot_port)
struct ocelot_port_private *priv = container_of(ocelot_port,
struct ocelot_port_private,
port);
+ struct ocelot *ocelot = ocelot_port->ocelot;
+ struct ocelot_fdma *fdma = ocelot->fdma;
unregister_netdev(priv->dev);
+ if (fdma)
+ ocelot_fdma_netdev_deinit(ocelot, priv->dev);
+
if (priv->phylink) {
rtnl_lock();
phylink_disconnect_phy(priv->phylink);
@@ -18,6 +18,7 @@
#include <soc/mscc/ocelot_vcap.h>
#include <soc/mscc/ocelot_hsio.h>
+#include "ocelot_fdma.h"
#include "ocelot.h"
#define VSC7514_VCAP_POLICER_BASE 128
@@ -1048,6 +1049,7 @@ static int mscc_ocelot_probe(struct platform_device *pdev)
{ S1, "s1" },
{ S2, "s2" },
{ PTP, "ptp", 1 },
+ { FDMA, "fdma", 1 },
};
if (!np && !pdev->dev.platform_data)
@@ -1083,6 +1085,9 @@ static int mscc_ocelot_probe(struct platform_device *pdev)
ocelot->targets[io_target[i].id] = target;
}
+ if (ocelot->targets[FDMA])
+ ocelot_fdma_init(pdev, ocelot);
+
hsio = syscon_regmap_lookup_by_compatible("mscc,ocelot-hsio");
if (IS_ERR(hsio)) {
dev_err(&pdev->dev, "missing hsio syscon\n");
@@ -1146,6 +1151,9 @@ static int mscc_ocelot_probe(struct platform_device *pdev)
if (err)
goto out_ocelot_devlink_unregister;
+ if (ocelot->fdma)
+ ocelot_fdma_start(ocelot);
+
err = ocelot_devlink_sb_register(ocelot);
if (err)
goto out_ocelot_release_ports;
@@ -1186,6 +1194,8 @@ static int mscc_ocelot_remove(struct platform_device *pdev)
{
struct ocelot *ocelot = platform_get_drvdata(pdev);
+ if (ocelot->fdma)
+ ocelot_fdma_deinit(ocelot);
devlink_unregister(ocelot->devlink);
ocelot_deinit_timestamp(ocelot);
ocelot_devlink_sb_unregister(ocelot);
@@ -118,6 +118,7 @@ enum ocelot_target {
S2,
HSIO,
PTP,
+ FDMA,
GCB,
DEV_GMII,
TARGET_MAX,
@@ -732,6 +733,8 @@ struct ocelot {
/* Protects the PTP clock */
spinlock_t ptp_clock_lock;
struct ptp_pin_desc ptp_pins[OCELOT_PTP_PINS_NUM];
+
+ struct ocelot_fdma *fdma;
};
struct ocelot_policer {