Adding upstream version 6.1.76.upstream/6.1.76

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 153 insertions, 0 deletions

diff --git a/drivers/net/ethernet/freescale/enetc/enetc_ierb.c b/drivers/net/ethernet/freescale/enetc/enetc_ierb.c
new file mode 100644
index 000000000..91f02c505
--- /dev/null
+++ b/drivers/net/ethernet/freescale/enetc/enetc_ierb.c
@@ -0,0 +1,153 @@
+// SPDX-License-Identifier: (GPL-2.0+ OR BSD-3-Clause)
+/* Copyright 2021 NXP
+ *
+ * The Integrated Endpoint Register Block (IERB) is configured by pre-boot
+ * software and is supposed to be to ENETC what a NVRAM is to a 'real' PCIe
+ * card. Upon FLR, values from the IERB are transferred to the ENETC PFs, and
+ * are read-only in the PF memory space.
+ *
+ * This driver fixes up the power-on reset values for the ENETC shared FIFO,
+ * such that the TX and RX allocations are sufficient for jumbo frames, and
+ * that intelligent FIFO dropping is enabled before the internal data
+ * structures are corrupted.
+ *
+ * Even though not all ports might be used on a given board, we are not
+ * concerned with partitioning the FIFO, because the default values configure
+ * no strict reservations, so the entire FIFO can be used by the RX of a single
+ * port, or the TX of a single port.
+ */
+
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/pci.h>
+#include <linux/platform_device.h>
+#include "enetc.h"
+#include "enetc_ierb.h"
+
+/* IERB registers */
+#define ENETC_IERB_TXMBAR(port)			(((port) * 0x100) + 0x8080)
+#define ENETC_IERB_RXMBER(port)			(((port) * 0x100) + 0x8090)
+#define ENETC_IERB_RXMBLR(port)			(((port) * 0x100) + 0x8094)
+#define ENETC_IERB_RXBCR(port)			(((port) * 0x100) + 0x80a0)
+#define ENETC_IERB_TXBCR(port)			(((port) * 0x100) + 0x80a8)
+#define ENETC_IERB_FMBDTR			0xa000
+
+#define ENETC_RESERVED_FOR_ICM			1024
+
+struct enetc_ierb {
+	void __iomem *regs;
+};
+
+static void enetc_ierb_write(struct enetc_ierb *ierb, u32 offset, u32 val)
+{
+	iowrite32(val, ierb->regs + offset);
+}
+
+int enetc_ierb_register_pf(struct platform_device *pdev,
+			   struct pci_dev *pf_pdev)
+{
+	struct enetc_ierb *ierb = platform_get_drvdata(pdev);
+	int port = enetc_pf_to_port(pf_pdev);
+	u16 tx_credit, rx_credit, tx_alloc;
+
+	if (port < 0)
+		return -ENODEV;
+
+	if (!ierb)
+		return -EPROBE_DEFER;
+
+	/* By default, it is recommended to set the Host Transfer Agent
+	 * per port transmit byte credit to "1000 + max_frame_size/2".
+	 * The power-on reset value (1800 bytes) is rounded up to the nearest
+	 * 100 assuming a maximum frame size of 1536 bytes.
+	 */
+	tx_credit = roundup(1000 + ENETC_MAC_MAXFRM_SIZE / 2, 100);
+
+	/* Internal memory allocated for transmit buffering is guaranteed but
+	 * not reserved; i.e. if the total transmit allocation is not used,
+	 * then the unused portion is not left idle, it can be used for receive
+	 * buffering but it will be reclaimed, if required, from receive by
+	 * intelligently dropping already stored receive frames in the internal
+	 * memory to ensure that the transmit allocation is respected.
+	 *
+	 * PaTXMBAR must be set to a value larger than
+	 *     PaTXBCR + 2 * max_frame_size + 32
+	 * if frame preemption is not enabled, or to
+	 *     2 * PaTXBCR + 2 * p_max_frame_size (pMAC maximum frame size) +
+	 *     2 * np_max_frame_size (eMAC maximum frame size) + 64
+	 * if frame preemption is enabled.
+	 */
+	tx_alloc = roundup(2 * tx_credit + 4 * ENETC_MAC_MAXFRM_SIZE + 64, 16);
+
+	/* Initial credits, in units of 8 bytes, to the Ingress Congestion
+	 * Manager for the maximum amount of bytes the port is allocated for
+	 * pending traffic.
+	 * It is recommended to set the initial credits to 2 times the maximum
+	 * frame size (2 frames of maximum size).
+	 */
+	rx_credit = DIV_ROUND_UP(ENETC_MAC_MAXFRM_SIZE * 2, 8);
+
+	enetc_ierb_write(ierb, ENETC_IERB_TXBCR(port), tx_credit);
+	enetc_ierb_write(ierb, ENETC_IERB_TXMBAR(port), tx_alloc);
+	enetc_ierb_write(ierb, ENETC_IERB_RXBCR(port), rx_credit);
+
+	return 0;
+}
+EXPORT_SYMBOL(enetc_ierb_register_pf);
+
+static int enetc_ierb_probe(struct platform_device *pdev)
+{
+	struct enetc_ierb *ierb;
+	void __iomem *regs;
+
+	ierb = devm_kzalloc(&pdev->dev, sizeof(*ierb), GFP_KERNEL);
+	if (!ierb)
+		return -ENOMEM;
+
+	regs = devm_platform_get_and_ioremap_resource(pdev, 0, NULL);
+	if (IS_ERR(regs))
+		return PTR_ERR(regs);
+
+	ierb->regs = regs;
+
+	/* Free buffer depletion threshold in bytes.
+	 * This sets the minimum amount of free buffer memory that should be
+	 * maintained in the datapath sub system, and when the amount of free
+	 * buffer memory falls below this threshold, a depletion indication is
+	 * asserted, which may trigger "intelligent drop" frame releases from
+	 * the ingress queues in the ICM.
+	 * It is recommended to set the free buffer depletion threshold to 1024
+	 * bytes, since the ICM needs some FIFO memory for its own use.
+	 */
+	enetc_ierb_write(ierb, ENETC_IERB_FMBDTR, ENETC_RESERVED_FOR_ICM);
+
+	platform_set_drvdata(pdev, ierb);
+
+	return 0;
+}
+
+static int enetc_ierb_remove(struct platform_device *pdev)
+{
+	return 0;
+}
+
+static const struct of_device_id enetc_ierb_match[] = {
+	{ .compatible = "fsl,ls1028a-enetc-ierb", },
+	{},
+};
+MODULE_DEVICE_TABLE(of, enetc_ierb_match);
+
+static struct platform_driver enetc_ierb_driver = {
+	.driver = {
+		.name = "fsl-enetc-ierb",
+		.of_match_table = enetc_ierb_match,
+	},
+	.probe = enetc_ierb_probe,
+	.remove = enetc_ierb_remove,
+};
+
+module_platform_driver(enetc_ierb_driver);
+
+MODULE_DESCRIPTION("NXP ENETC IERB");
+MODULE_LICENSE("Dual BSD/GPL");