From d1158f0282304c89217894aa346fc45364b95542 Mon Sep 17 00:00:00 2001
From: Luo Jie <quic_luoj@quicinc.com>
Date: Sun, 9 Feb 2025 22:29:37 +0800
Subject: [PATCH] net: ethernet: qualcomm: Add PPE driver for IPQ9574 SoC

The PPE (Packet Process Engine) hardware block is available
on Qualcomm IPQ SoC that support PPE architecture, such as
IPQ9574.

The PPE in IPQ9574 includes six integrated ethernet MAC
(for 6 PPE ports), buffer management, queue management and
scheduler functions. The MACs can connect with the external
PHY or switch devices using the UNIPHY PCS block available
in the SoC.

The PPE also includes various packet processing offload
capabilities such as L3 routing and L2 bridging, VLAN and
tunnel processing offload. It also includes Ethernet DMA
function for transferring packets between ARM cores and
PPE ethernet ports.

This patch adds the base source files and Makefiles for
the PPE driver such as platform driver registration,
clock initialization, and PPE reset routines.

Signed-off-by: Luo Jie <quic_luoj@quicinc.com>
---
 drivers/net/ethernet/qualcomm/Kconfig      |  15 ++
 drivers/net/ethernet/qualcomm/Makefile     |   1 +
 drivers/net/ethernet/qualcomm/ppe/Makefile |   7 +
 drivers/net/ethernet/qualcomm/ppe/ppe.c    | 218 +++++++++++++++++++++
 drivers/net/ethernet/qualcomm/ppe/ppe.h    |  36 ++++
 5 files changed, 277 insertions(+)
 create mode 100644 drivers/net/ethernet/qualcomm/ppe/Makefile
 create mode 100644 drivers/net/ethernet/qualcomm/ppe/ppe.c
 create mode 100644 drivers/net/ethernet/qualcomm/ppe/ppe.h

--- a/drivers/net/ethernet/qualcomm/Kconfig
+++ b/drivers/net/ethernet/qualcomm/Kconfig
@@ -61,6 +61,21 @@ config QCOM_EMAC
 	  low power, Receive-Side Scaling (RSS), and IEEE 1588-2008
 	  Precision Clock Synchronization Protocol.
 
+config QCOM_PPE
+	tristate "Qualcomm Technologies, Inc. PPE Ethernet support"
+	depends on HAS_IOMEM && OF
+	depends on COMMON_CLK
+	select REGMAP_MMIO
+	help
+	  This driver supports the Qualcomm Technologies, Inc. packet
+	  process engine (PPE) available with IPQ SoC. The PPE includes
+	  the ethernet MACs, Ethernet DMA (EDMA) and switch core that
+	  supports L3 flow offload, L2 switch function, RSS and tunnel
+	  offload.
+
+	  To compile this driver as a module, choose M here. The module
+	  will be called qcom-ppe.
+
 source "drivers/net/ethernet/qualcomm/rmnet/Kconfig"
 
 endif # NET_VENDOR_QUALCOMM
--- a/drivers/net/ethernet/qualcomm/Makefile
+++ b/drivers/net/ethernet/qualcomm/Makefile
@@ -11,4 +11,5 @@ qcauart-objs := qca_uart.o
 
 obj-y += emac/
 
+obj-$(CONFIG_QCOM_PPE) += ppe/
 obj-$(CONFIG_RMNET) += rmnet/
--- /dev/null
+++ b/drivers/net/ethernet/qualcomm/ppe/Makefile
@@ -0,0 +1,7 @@
+# SPDX-License-Identifier: GPL-2.0-only
+#
+# Makefile for the device driver of PPE (Packet Process Engine) in IPQ SoC
+#
+
+obj-$(CONFIG_QCOM_PPE) += qcom-ppe.o
+qcom-ppe-objs := ppe.o
--- /dev/null
+++ b/drivers/net/ethernet/qualcomm/ppe/ppe.c
@@ -0,0 +1,218 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2025 Qualcomm Innovation Center, Inc. All rights reserved.
+ */
+
+/* PPE platform device probe, DTSI parser and PPE clock initializations. */
+
+#include <linux/clk.h>
+#include <linux/interconnect.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/reset.h>
+
+#include "ppe.h"
+
+#define PPE_PORT_MAX		8
+#define PPE_CLK_RATE		353000000
+
+/* ICC clocks for enabling PPE device. The avg_bw and peak_bw with value 0
+ * will be updated by the clock rate of PPE.
+ */
+static const struct icc_bulk_data ppe_icc_data[] = {
+	{
+		.name = "ppe",
+		.avg_bw = 0,
+		.peak_bw = 0,
+	},
+	{
+		.name = "ppe_cfg",
+		.avg_bw = 0,
+		.peak_bw = 0,
+	},
+	{
+		.name = "qos_gen",
+		.avg_bw = 6000,
+		.peak_bw = 6000,
+	},
+	{
+		.name = "timeout_ref",
+		.avg_bw = 6000,
+		.peak_bw = 6000,
+	},
+	{
+		.name = "nssnoc_memnoc",
+		.avg_bw = 533333,
+		.peak_bw = 533333,
+	},
+	{
+		.name = "memnoc_nssnoc",
+		.avg_bw = 533333,
+		.peak_bw = 533333,
+	},
+	{
+		.name = "memnoc_nssnoc_1",
+		.avg_bw = 533333,
+		.peak_bw = 533333,
+	},
+};
+
+static const struct regmap_range ppe_readable_ranges[] = {
+	regmap_reg_range(0x0, 0x1ff),		/* Global */
+	regmap_reg_range(0x400, 0x5ff),		/* LPI CSR */
+	regmap_reg_range(0x1000, 0x11ff),	/* GMAC0 */
+	regmap_reg_range(0x1200, 0x13ff),	/* GMAC1 */
+	regmap_reg_range(0x1400, 0x15ff),	/* GMAC2 */
+	regmap_reg_range(0x1600, 0x17ff),	/* GMAC3 */
+	regmap_reg_range(0x1800, 0x19ff),	/* GMAC4 */
+	regmap_reg_range(0x1a00, 0x1bff),	/* GMAC5 */
+	regmap_reg_range(0xb000, 0xefff),	/* PRX CSR */
+	regmap_reg_range(0xf000, 0x1efff),	/* IPE */
+	regmap_reg_range(0x20000, 0x5ffff),	/* PTX CSR */
+	regmap_reg_range(0x60000, 0x9ffff),	/* IPE L2 CSR */
+	regmap_reg_range(0xb0000, 0xeffff),	/* IPO CSR */
+	regmap_reg_range(0x100000, 0x17ffff),	/* IPE PC */
+	regmap_reg_range(0x180000, 0x1bffff),	/* PRE IPO CSR */
+	regmap_reg_range(0x1d0000, 0x1dffff),	/* Tunnel parser */
+	regmap_reg_range(0x1e0000, 0x1effff),	/* Ingress parse */
+	regmap_reg_range(0x200000, 0x2fffff),	/* IPE L3 */
+	regmap_reg_range(0x300000, 0x3fffff),	/* IPE tunnel */
+	regmap_reg_range(0x400000, 0x4fffff),	/* Scheduler */
+	regmap_reg_range(0x500000, 0x503fff),	/* XGMAC0 */
+	regmap_reg_range(0x504000, 0x507fff),	/* XGMAC1 */
+	regmap_reg_range(0x508000, 0x50bfff),	/* XGMAC2 */
+	regmap_reg_range(0x50c000, 0x50ffff),	/* XGMAC3 */
+	regmap_reg_range(0x510000, 0x513fff),	/* XGMAC4 */
+	regmap_reg_range(0x514000, 0x517fff),	/* XGMAC5 */
+	regmap_reg_range(0x600000, 0x6fffff),	/* BM */
+	regmap_reg_range(0x800000, 0x9fffff),	/* QM */
+	regmap_reg_range(0xb00000, 0xbef800),	/* EDMA */
+};
+
+static const struct regmap_access_table ppe_reg_table = {
+	.yes_ranges = ppe_readable_ranges,
+	.n_yes_ranges = ARRAY_SIZE(ppe_readable_ranges),
+};
+
+static const struct regmap_config regmap_config_ipq9574 = {
+	.reg_bits = 32,
+	.reg_stride = 4,
+	.val_bits = 32,
+	.rd_table = &ppe_reg_table,
+	.wr_table = &ppe_reg_table,
+	.max_register = 0xbef800,
+	.fast_io = true,
+};
+
+static int ppe_clock_init_and_reset(struct ppe_device *ppe_dev)
+{
+	unsigned long ppe_rate = ppe_dev->clk_rate;
+	struct device *dev = ppe_dev->dev;
+	struct reset_control *rstc;
+	struct clk_bulk_data *clks;
+	struct clk *clk;
+	int ret, i;
+
+	for (i = 0; i < ppe_dev->num_icc_paths; i++) {
+		ppe_dev->icc_paths[i].name = ppe_icc_data[i].name;
+		ppe_dev->icc_paths[i].avg_bw = ppe_icc_data[i].avg_bw ? :
+					       Bps_to_icc(ppe_rate);
+		ppe_dev->icc_paths[i].peak_bw = ppe_icc_data[i].peak_bw ? :
+						Bps_to_icc(ppe_rate);
+	}
+
+	ret = devm_of_icc_bulk_get(dev, ppe_dev->num_icc_paths,
+				   ppe_dev->icc_paths);
+	if (ret)
+		return ret;
+
+	ret = icc_bulk_set_bw(ppe_dev->num_icc_paths, ppe_dev->icc_paths);
+	if (ret)
+		return ret;
+
+	/* The PPE clocks have a common parent clock. Setting the clock
+	 * rate of "ppe" ensures the clock rate of all PPE clocks is
+	 * configured to the same rate.
+	 */
+	clk = devm_clk_get(dev, "ppe");
+	if (IS_ERR(clk))
+		return PTR_ERR(clk);
+
+	ret = clk_set_rate(clk, ppe_rate);
+	if (ret)
+		return ret;
+
+	ret = devm_clk_bulk_get_all_enable(dev, &clks);
+	if (ret < 0)
+		return ret;
+
+	/* Reset the PPE. */
+	rstc = devm_reset_control_get_exclusive(dev, NULL);
+	if (IS_ERR(rstc))
+		return PTR_ERR(rstc);
+
+	ret = reset_control_assert(rstc);
+	if (ret)
+		return ret;
+
+	/* The delay 10 ms of assert is necessary for resetting PPE. */
+	usleep_range(10000, 11000);
+
+	return reset_control_deassert(rstc);
+}
+
+static int qcom_ppe_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct ppe_device *ppe_dev;
+	void __iomem *base;
+	int ret, num_icc;
+
+	num_icc = ARRAY_SIZE(ppe_icc_data);
+	ppe_dev = devm_kzalloc(dev, struct_size(ppe_dev, icc_paths, num_icc),
+			       GFP_KERNEL);
+	if (!ppe_dev)
+		return -ENOMEM;
+
+	base = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(base))
+		return dev_err_probe(dev, PTR_ERR(base), "PPE ioremap failed\n");
+
+	ppe_dev->regmap = devm_regmap_init_mmio(dev, base, &regmap_config_ipq9574);
+	if (IS_ERR(ppe_dev->regmap))
+		return dev_err_probe(dev, PTR_ERR(ppe_dev->regmap),
+				     "PPE initialize regmap failed\n");
+	ppe_dev->dev = dev;
+	ppe_dev->clk_rate = PPE_CLK_RATE;
+	ppe_dev->num_ports = PPE_PORT_MAX;
+	ppe_dev->num_icc_paths = num_icc;
+
+	ret = ppe_clock_init_and_reset(ppe_dev);
+	if (ret)
+		return dev_err_probe(dev, ret, "PPE clock config failed\n");
+
+	platform_set_drvdata(pdev, ppe_dev);
+
+	return 0;
+}
+
+static const struct of_device_id qcom_ppe_of_match[] = {
+	{ .compatible = "qcom,ipq9574-ppe" },
+	{}
+};
+MODULE_DEVICE_TABLE(of, qcom_ppe_of_match);
+
+static struct platform_driver qcom_ppe_driver = {
+	.driver = {
+		.name = "qcom_ppe",
+		.of_match_table = qcom_ppe_of_match,
+	},
+	.probe	= qcom_ppe_probe,
+};
+module_platform_driver(qcom_ppe_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Qualcomm Technologies, Inc. IPQ PPE driver");
--- /dev/null
+++ b/drivers/net/ethernet/qualcomm/ppe/ppe.h
@@ -0,0 +1,36 @@
+/* SPDX-License-Identifier: GPL-2.0-only
+ *
+ * Copyright (c) 2025 Qualcomm Innovation Center, Inc. All rights reserved.
+ */
+
+#ifndef __PPE_H__
+#define __PPE_H__
+
+#include <linux/compiler.h>
+#include <linux/interconnect.h>
+
+struct device;
+struct regmap;
+
+/**
+ * struct ppe_device - PPE device private data.
+ * @dev: PPE device structure.
+ * @regmap: PPE register map.
+ * @clk_rate: PPE clock rate.
+ * @num_ports: Number of PPE ports.
+ * @num_icc_paths: Number of interconnect paths.
+ * @icc_paths: Interconnect path array.
+ *
+ * PPE device is the instance of PPE hardware, which is used to
+ * configure PPE packet process modules such as BM (buffer management),
+ * QM (queue management), and scheduler.
+ */
+struct ppe_device {
+	struct device *dev;
+	struct regmap *regmap;
+	unsigned long clk_rate;
+	unsigned int num_ports;
+	unsigned int num_icc_paths;
+	struct icc_bulk_data icc_paths[] __counted_by(num_icc_paths);
+};
+#endif
