enetc: Introduce basic PF and VF ENETC ethernet drivers

ENETC is a multi-port virtualized Ethernet controller supporting GbE
designs and Time-Sensitive Networking (TSN) functionality.
ENETC is operating as an SR-IOV multi-PF capable Root Complex Integrated
Endpoint (RCIE).  As such, it contains multiple physical (PF) and
virtual (VF) PCIe functions, discoverable by standard PCI Express.

Introduce basic PF and VF ENETC ethernet drivers.  The PF has access to
the ENETC Port registers and resources and makes the required privileged
configurations for the underlying VF devices.  Common functionality is
controlled through so called System Interface (SI) register blocks, PFs
and VFs own a SI each.  Though SI register blocks are almost identical,
there are a few privileged SI level controls that are accessible only to
PFs, and so the distinction is made between PF SIs (PSI) and VF SIs (VSI).
As such, the bulk of the code, including datapath processing, basic h/w
offload support and generic pci related configuration, is shared between
the 2 drivers and is factored out in common source files (i.e. enetc.c).

Major functionalities included (for both drivers):
MSI-X support for Rx and Tx processing, assignment of Rx/Tx BD ring pairs
to MSI-X entries, multi-queue support, Rx S/G (Rx frame fragmentation) and
jumbo frame (up to 9600B) support, Rx paged allocation and reuse, Tx S/G
support (NETIF_F_SG), Rx and Tx checksum offload, PF MAC filtering and
initial control ring support, VLAN extraction/ insertion, PF Rx VLAN
CTAG filtering, VF mac address config support, VF VLAN isolation support,
etc.

Signed-off-by: Claudiu Manoil <claudiu.manoil@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 110 insertions, 0 deletions

diff --git a/drivers/net/ethernet/freescale/enetc/enetc_cbdr.c b/drivers/net/ethernet/freescale/enetc/enetc_cbdr.c
new file mode 100644
index 000000000000..2ec0f2f316be
--- /dev/null
+++ b/drivers/net/ethernet/freescale/enetc/enetc_cbdr.c
@@ -0,0 +1,110 @@
+// SPDX-License-Identifier: (GPL-2.0+ OR BSD-3-Clause)
+/* Copyright 2017-2019 NXP */
+
+#include "enetc.h"
+
+static void enetc_clean_cbdr(struct enetc_si *si)
+{
+	struct enetc_cbdr *ring = &si->cbd_ring;
+	struct enetc_cbd *dest_cbd;
+	int i, status;
+
+	i = ring->next_to_clean;
+
+	while (enetc_rd_reg(ring->cir) != i) {
+		dest_cbd = ENETC_CBD(*ring, i);
+		status = dest_cbd->status_flags & ENETC_CBD_STATUS_MASK;
+		if (status)
+			dev_warn(&si->pdev->dev, "CMD err %04x for cmd %04x\n",
+				 status, dest_cbd->cmd);
+
+		memset(dest_cbd, 0, sizeof(*dest_cbd));
+
+		i = (i + 1) % ring->bd_count;
+	}
+
+	ring->next_to_clean = i;
+}
+
+static int enetc_cbd_unused(struct enetc_cbdr *r)
+{
+	return (r->next_to_clean - r->next_to_use - 1 + r->bd_count) %
+		r->bd_count;
+}
+
+static int enetc_send_cmd(struct enetc_si *si, struct enetc_cbd *cbd)
+{
+	struct enetc_cbdr *ring = &si->cbd_ring;
+	int timeout = ENETC_CBDR_TIMEOUT;
+	struct enetc_cbd *dest_cbd;
+	int i;
+
+	if (unlikely(!ring->bd_base))
+		return -EIO;
+
+	if (unlikely(!enetc_cbd_unused(ring)))
+		enetc_clean_cbdr(si);
+
+	i = ring->next_to_use;
+	dest_cbd = ENETC_CBD(*ring, i);
+
+	/* copy command to the ring */
+	*dest_cbd = *cbd;
+	i = (i + 1) % ring->bd_count;
+
+	ring->next_to_use = i;
+	/* let H/W know BD ring has been updated */
+	enetc_wr_reg(ring->pir, i);
+
+	do {
+		if (enetc_rd_reg(ring->cir) == i)
+			break;
+		udelay(10); /* cannot sleep, rtnl_lock() */
+		timeout -= 10;
+	} while (timeout);
+
+	if (!timeout)
+		return -EBUSY;
+
+	enetc_clean_cbdr(si);
+
+	return 0;
+}
+
+int enetc_clear_mac_flt_entry(struct enetc_si *si, int index)
+{
+	struct enetc_cbd cbd;
+
+	memset(&cbd, 0, sizeof(cbd));
+
+	cbd.cls = 1;
+	cbd.status_flags = ENETC_CBD_FLAGS_SF;
+	cbd.index = cpu_to_le16(index);
+
+	return enetc_send_cmd(si, &cbd);
+}
+
+int enetc_set_mac_flt_entry(struct enetc_si *si, int index,
+			    char *mac_addr, int si_map)
+{
+	struct enetc_cbd cbd;
+	u32 upper;
+	u16 lower;
+
+	memset(&cbd, 0, sizeof(cbd));
+
+	/* fill up the "set" descriptor */
+	cbd.cls = 1;
+	cbd.status_flags = ENETC_CBD_FLAGS_SF;
+	cbd.index = cpu_to_le16(index);
+	cbd.opt[3] = cpu_to_le32(si_map);
+	/* enable entry */
+	cbd.opt[0] = cpu_to_le32(BIT(31));
+
+	upper = *(const u32 *)mac_addr;
+	lower = *(const u16 *)(mac_addr + 4);
+	cbd.addr[0] = cpu_to_le32(upper);
+	cbd.addr[1] = cpu_to_le32(lower);
+
+	return enetc_send_cmd(si, &cbd);
+}