Message-ID: <20201118082935.26828-3-jianjun.wang@mediatek.com>
Date:   Wed, 18 Nov 2020 16:29:34 +0800
From:   Jianjun Wang <jianjun.wang@...iatek.com>
To:     Bjorn Helgaas <bhelgaas@...gle.com>,
        Rob Herring <robh+dt@...nel.org>,
        Lorenzo Pieralisi <lorenzo.pieralisi@....com>,
        Ryder Lee <ryder.lee@...iatek.com>
CC:     Philipp Zabel <p.zabel@...gutronix.de>,
        Matthias Brugger <matthias.bgg@...il.com>,
        Mauro Carvalho Chehab <mchehab+huawei@...nel.org>,
        <davem@...emloft.net>, <linux-pci@...r.kernel.org>,
        <linux-mediatek@...ts.infradead.org>, <devicetree@...r.kernel.org>,
        <linux-kernel@...r.kernel.org>,
        <linux-arm-kernel@...ts.infradead.org>,
        Sj Huang <sj.huang@...iatek.com>,
        Jianjun Wang <jianjun.wang@...iatek.com>,
        <youlin.pei@...iatek.com>, <chuanjia.liu@...iatek.com>,
        <qizhong.cheng@...iatek.com>, <sin_jieyang@...iatek.com>
Subject: [v4,2/3] PCI: mediatek: Add new generation controller support

MediaTek's PCIe host controller has three generation HWs, the new
generation HW is an individual bridge, it supoorts Gen3 speed and
up to 256 MSI interrupt numbers for multi-function devices.

Add support for new Gen3 controller which can be found on MT8192.

Signed-off-by: Jianjun Wang <jianjun.wang@...iatek.com>
Acked-by: Ryder Lee <ryder.lee@...iatek.com>
---
 drivers/pci/controller/Kconfig              |   14 +
 drivers/pci/controller/Makefile             |    1 +
 drivers/pci/controller/pcie-mediatek-gen3.c | 1031 +++++++++++++++++++
 3 files changed, 1046 insertions(+)
 create mode 100644 drivers/pci/controller/pcie-mediatek-gen3.c

diff --git a/drivers/pci/controller/Kconfig b/drivers/pci/controller/Kconfig
index f18c3725ef80..83daa772595b 100644
--- a/drivers/pci/controller/Kconfig
+++ b/drivers/pci/controller/Kconfig
@@ -239,6 +239,20 @@ config PCIE_MEDIATEK
 	  Say Y here if you want to enable PCIe controller support on
 	  MediaTek SoCs.
 
+config PCIE_MEDIATEK_GEN3
+	tristate "MediaTek GEN3 PCIe controller"
+	depends on ARCH_MEDIATEK || COMPILE_TEST
+	depends on OF
+	depends on PCI_MSI_IRQ_DOMAIN
+	help
+	  Adds support for PCIe Gen3 MAC controller for MediaTek SoCs.
+	  This PCIe controller provides the capable of Gen3, Gen2 and
+	  Gen1 speed, and support up to 256 MSI interrupt numbers for
+	  multi-function devices.
+
+	  Say Y here if you want to enable Gen3 PCIe controller support on
+	  MediaTek SoCs.
+
 config PCIE_TANGO_SMP8759
 	bool "Tango SMP8759 PCIe controller (DANGEROUS)"
 	depends on ARCH_TANGO && PCI_MSI && OF
diff --git a/drivers/pci/controller/Makefile b/drivers/pci/controller/Makefile
index bcdbf49ab1e4..9c1b96777597 100644
--- a/drivers/pci/controller/Makefile
+++ b/drivers/pci/controller/Makefile
@@ -27,6 +27,7 @@ obj-$(CONFIG_PCIE_ROCKCHIP) += pcie-rockchip.o
 obj-$(CONFIG_PCIE_ROCKCHIP_EP) += pcie-rockchip-ep.o
 obj-$(CONFIG_PCIE_ROCKCHIP_HOST) += pcie-rockchip-host.o
 obj-$(CONFIG_PCIE_MEDIATEK) += pcie-mediatek.o
+obj-$(CONFIG_PCIE_MEDIATEK_GEN3) += pcie-mediatek-gen3.o
 obj-$(CONFIG_PCIE_TANGO_SMP8759) += pcie-tango.o
 obj-$(CONFIG_VMD) += vmd.o
 obj-$(CONFIG_PCIE_BRCMSTB) += pcie-brcmstb.o
diff --git a/drivers/pci/controller/pcie-mediatek-gen3.c b/drivers/pci/controller/pcie-mediatek-gen3.c
new file mode 100644
index 000000000000..dd454cfee373
--- /dev/null
+++ b/drivers/pci/controller/pcie-mediatek-gen3.c
@@ -0,0 +1,1031 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * MediaTek PCIe host controller driver.
+ *
+ * Copyright (c) 2020 MediaTek Inc.
+ * Author: Jianjun Wang <jianjun.wang@...iatek.com>
+ */
+
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/iopoll.h>
+#include <linux/irq.h>
+#include <linux/irqchip/chained_irq.h>
+#include <linux/irqdomain.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/msi.h>
+#include <linux/of_address.h>
+#include <linux/of_clk.h>
+#include <linux/of_pci.h>
+#include <linux/of_platform.h>
+#include <linux/pci.h>
+#include <linux/phy/phy.h>
+#include <linux/platform_device.h>
+#include <linux/pm_domain.h>
+#include <linux/pm_runtime.h>
+#include <linux/reset.h>
+
+#include "../pci.h"
+
+#define PCIE_SETTING_REG		0x80
+#define PCIE_PCI_IDS_1			0x9c
+#define PCI_CLASS(class)		(class << 8)
+#define PCIE_RC_MODE			BIT(0)
+
+#define PCIE_CFGNUM_REG			0x140
+#define PCIE_CFG_DEVFN(devfn)		((devfn) & GENMASK(7, 0))
+#define PCIE_CFG_BUS(bus)		(((bus) << 8) & GENMASK(15, 8))
+#define PCIE_CFG_BYTE_EN(bytes)		(((bytes) << 16) & GENMASK(19, 16))
+#define PCIE_CFG_FORCE_BYTE_EN		BIT(20)
+#define PCIE_CFG_OFFSET_ADDR		0x1000
+#define PCIE_CFG_HEADER(devfn, bus) \
+	(PCIE_CFG_DEVFN(devfn) | PCIE_CFG_BUS(bus))
+
+#define PCIE_CFG_HEADER_FORCE_BE(devfn, bus, bytes) \
+	(PCIE_CFG_HEADER(devfn, bus) | PCIE_CFG_BYTE_EN(bytes) \
+	 | PCIE_CFG_FORCE_BYTE_EN)
+
+#define PCIE_RST_CTRL_REG		0x148
+#define PCIE_MAC_RSTB			BIT(0)
+#define PCIE_PHY_RSTB			BIT(1)
+#define PCIE_BRG_RSTB			BIT(2)
+#define PCIE_PE_RSTB			BIT(3)
+
+#define PCIE_MISC_STATUS_REG		0x14C
+#define PCIE_LTR_MSG_RECEIVED		BIT(0)
+#define PCIE_PCIE_MSG_RECEIVED		BIT(1)
+
+#define PCIE_LTSSM_STATUS_REG		0x150
+#define PCIE_LTSSM_STATE_MASK		GENMASK(28, 24)
+#define PCIE_LTSSM_STATE(val)		((val & PCIE_LTSSM_STATE_MASK) >> 24)
+#define PCIE_LTSSM_STATE_L0		0x10
+#define PCIE_LTSSM_STATE_L1_IDLE	0x13
+#define PCIE_LTSSM_STATE_L2_IDLE	0x14
+
+#define PCIE_LINK_STATUS_REG		0x154
+#define PCIE_PORT_LINKUP		BIT(8)
+
+#define PCIE_MSI_SET_NUM		8
+#define PCIE_MSI_IRQS_PER_SET		32
+#define PCIE_MSI_IRQS_NUM \
+	(PCIE_MSI_IRQS_PER_SET * (PCIE_MSI_SET_NUM))
+
+#define PCIE_INT_ENABLE_REG		0x180
+#define PCIE_MSI_MASK			GENMASK(PCIE_MSI_SET_NUM + 8 - 1, 8)
+#define PCIE_MSI_SHIFT			8
+#define PCIE_INTX_SHIFT			24
+#define PCIE_INTX_MASK			GENMASK(27, 24)
+#define PCIE_MSG_MASK			BIT(28)
+#define PCIE_AER_MASK			BIT(29)
+#define PCIE_PM_MASK			BIT(30)
+
+#define PCIE_INT_STATUS_REG		0x184
+#define PCIE_MSI_SET_ENABLE_REG		0x190
+
+#define PCIE_LOW_POWER_CTRL_REG		0x194
+#define PCIE_DIS_LOWPWR_MASK		GENMASK(3, 0)
+#define PCIE_DIS_L0S_MASK		BIT(0)
+#define PCIE_DIS_L1_MASK		BIT(1)
+#define PCIE_DIS_L11_MASK		BIT(2)
+#define PCIE_DIS_L12_MASK		BIT(3)
+#define PCIE_FORCE_DIS_LOWPWR		GENMASK(11, 8)
+#define PCIE_FORCE_DIS_L0S		BIT(8)
+#define PCIE_FORCE_DIS_L1		BIT(9)
+#define PCIE_FORCE_DIS_L11		BIT(10)
+#define PCIE_FORCE_DIS_L12		BIT(11)
+
+#define PCIE_ICMD_PM_REG		0x198
+#define PCIE_TURN_OFF_LINK		BIT(4)
+
+#define PCIE_MSI_ADDR_BASE_REG		0xc00
+#define PCIE_MSI_SET_OFFSET		0x10
+#define PCIE_MSI_STATUS_OFFSET		0x04
+#define PCIE_MSI_ENABLE_OFFSET		0x08
+
+#define PCIE_TRANS_TABLE_BASE_REG	0x800
+#define PCIE_ATR_SRC_ADDR_MSB_OFFSET	0x4
+#define PCIE_ATR_TRSL_ADDR_LSB_OFFSET	0x8
+#define PCIE_ATR_TRSL_ADDR_MSB_OFFSET	0xc
+#define PCIE_ATR_TRSL_PARAM_OFFSET	0x10
+#define PCIE_ATR_TLB_SET_OFFSET		0x20
+
+#define PCIE_MAX_TRANS_TABLES		8
+#define ATR_EN				BIT(0)
+#define ATR_SIZE(size)			((((size) - 1) << 1) & GENMASK(6, 1))
+#define ATR_ID(id)			(id & GENMASK(3, 0))
+#define ATR_PARAM(param)		(((param) << 16) & GENMASK(27, 16))
+
+/**
+ * struct mtk_pcie_msi - MSI information for each set
+ * @base: IO mapped register base
+ * @irq: MSI set Interrupt number
+ * @index: MSI set number
+ * @msg_addr: MSI message address
+ * @domain: IRQ domain
+ */
+struct mtk_pcie_msi {
+	void __iomem *base;
+	unsigned int irq;
+	int index;
+	phys_addr_t msg_addr;
+	struct irq_domain *domain;
+};
+
+/**
+ * struct mtk_pcie_port - PCIe port information
+ * @dev: PCIe device
+ * @base: IO mapped register base
+ * @reg_base: Physical register base
+ * @mac_reset: mac reset control
+ * @phy_reset: phy reset control
+ * @phy: PHY controller block
+ * @clks: PCIe clocks
+ * @num_clks: PCIe clocks count for this port
+ * @is_suspended: device suspend state
+ * @irq: PCIe controller interrupt number
+ * @intx_domain: legacy INTx IRQ domain
+ * @msi_domain: MSI IRQ domain
+ * @msi_top_domain: MSI IRQ top domain
+ * @msi_info: MSI sets information
+ * @lock: lock protecting IRQ bit map
+ * @msi_irq_in_use: bit map for assigned MSI IRQ
+ */
+struct mtk_pcie_port {
+	struct device *dev;
+	void __iomem *base;
+	phys_addr_t reg_base;
+	struct reset_control *mac_reset;
+	struct reset_control *phy_reset;
+	struct phy *phy;
+	struct clk_bulk_data *clks;
+	int num_clks;
+	bool is_suspended;
+
+	int irq;
+	struct irq_domain *intx_domain;
+	struct irq_domain *msi_domain;
+	struct irq_domain *msi_top_domain;
+	struct mtk_pcie_msi **msi_info;
+	struct mutex lock;
+	DECLARE_BITMAP(msi_irq_in_use, PCIE_MSI_IRQS_NUM);
+};
+
+static int mtk_pcie_config_read(struct pci_bus *bus, unsigned int devfn,
+				    int where, int size, u32 *val)
+{
+	struct mtk_pcie_port *port = bus->sysdata;
+	int bytes;
+
+	bytes = ((1 << size) - 1) << (where & 0x3);
+	writel(PCIE_CFG_HEADER_FORCE_BE(devfn, bus->number, bytes),
+	       port->base + PCIE_CFGNUM_REG);
+
+	*val = readl(port->base + PCIE_CFG_OFFSET_ADDR + (where & ~0x3));
+
+	if (size <= 2)
+		*val = (*val >> (8 * (where & 0x3))) & ((1 << (size * 8)) - 1);
+
+	return PCIBIOS_SUCCESSFUL;
+}
+
+static int mtk_pcie_config_write(struct pci_bus *bus, unsigned int devfn,
+				     int where, int size, u32 val)
+{
+	struct mtk_pcie_port *port = bus->sysdata;
+	int bytes;
+
+	bytes = ((1 << size) - 1) << (where & 0x3);
+	writel(PCIE_CFG_HEADER_FORCE_BE(devfn, bus->number, bytes),
+	       port->base + PCIE_CFGNUM_REG);
+
+	if (size <= 2)
+		val = (val & ((1 << (size * 8)) - 1)) << ((where & 0x3) * 8);
+
+	writel(val, port->base + PCIE_CFG_OFFSET_ADDR + (where & ~0x3));
+
+	return PCIBIOS_SUCCESSFUL;
+}
+
+static struct pci_ops mtk_pcie_ops = {
+	.read  = mtk_pcie_config_read,
+	.write = mtk_pcie_config_write,
+};
+
+static void mtk_pcie_set_trans_window(void __iomem *reg,
+				      resource_size_t cpu_addr,
+				      resource_size_t pci_addr, size_t size)
+{
+	writel(lower_32_bits(cpu_addr) | ATR_SIZE(fls(size) - 1) | ATR_EN, reg);
+	writel(upper_32_bits(cpu_addr), reg + PCIE_ATR_SRC_ADDR_MSB_OFFSET);
+	writel(lower_32_bits(pci_addr), reg + PCIE_ATR_TRSL_ADDR_LSB_OFFSET);
+	writel(upper_32_bits(pci_addr), reg + PCIE_ATR_TRSL_ADDR_MSB_OFFSET);
+	writel(ATR_ID(0) | ATR_PARAM(0), reg + PCIE_ATR_TRSL_PARAM_OFFSET);
+}
+
+static int mtk_pcie_set_trans_table(void __iomem *reg,
+				    resource_size_t cpu_addr,
+				    resource_size_t pci_addr, size_t size,
+				    int num)
+{
+	void __iomem *table_base;
+
+	if (num > PCIE_MAX_TRANS_TABLES)
+		return -ENODEV;
+
+	table_base = reg + num * PCIE_ATR_TLB_SET_OFFSET;
+	mtk_pcie_set_trans_window(table_base, cpu_addr, pci_addr, size);
+
+	return 0;
+}
+
+static int mtk_pcie_startup_port(struct mtk_pcie_port *port)
+{
+	struct resource_entry *entry;
+	struct pci_host_bridge *host = pci_host_bridge_from_priv(port);
+	unsigned int table_index = 0;
+	int err;
+	u32 val;
+
+	/* Set as RC mode */
+	val = readl(port->base + PCIE_SETTING_REG);
+	val |= PCIE_RC_MODE;
+	writel(val, port->base + PCIE_SETTING_REG);
+
+	/* Set class code */
+	val = readl(port->base + PCIE_PCI_IDS_1);
+	val &= ~GENMASK(31, 8);
+	val |= PCI_CLASS(PCI_CLASS_BRIDGE_PCI << 8);
+	writel(val, port->base + PCIE_PCI_IDS_1);
+
+	/* Assert all reset signals */
+	val = readl(port->base + PCIE_RST_CTRL_REG);
+	val |= PCIE_MAC_RSTB | PCIE_PHY_RSTB | PCIE_BRG_RSTB | PCIE_PE_RSTB;
+	writel(val, port->base + PCIE_RST_CTRL_REG);
+
+	/* De-assert reset signals*/
+	val &= ~(PCIE_MAC_RSTB | PCIE_PHY_RSTB | PCIE_BRG_RSTB);
+	writel(val, port->base + PCIE_RST_CTRL_REG);
+
+	/* Delay 100ms to wait the reference clocks become stable */
+	usleep_range(100 * 1000, 120 * 1000);
+
+	/* De-assert pe reset*/
+	val &= ~PCIE_PE_RSTB;
+	writel(val, port->base + PCIE_RST_CTRL_REG);
+
+	/* Check if the link is up or not */
+	err = readl_poll_timeout(port->base + PCIE_LINK_STATUS_REG, val,
+			!!(val & PCIE_PORT_LINKUP), 20,
+			50 * USEC_PER_MSEC);
+	if (err) {
+		val = readl(port->base + PCIE_LTSSM_STATUS_REG);
+		dev_dbg(port->dev, "ltssm reg val: %#x\n", val);
+		return err;
+	}
+
+	/* Set PCIe translation windows */
+	resource_list_for_each_entry(entry, &host->windows) {
+		unsigned long type = resource_type(entry->res);
+		struct resource *res = NULL;
+		resource_size_t cpu_addr;
+		resource_size_t pci_addr;
+
+		if (!(type & (IORESOURCE_MEM | IORESOURCE_IO)))
+			continue;
+
+		res = entry->res;
+		cpu_addr = res->start;
+		pci_addr = res->start - entry->offset;
+		mtk_pcie_set_trans_table(port->base + PCIE_TRANS_TABLE_BASE_REG,
+					 cpu_addr, pci_addr, resource_size(res),
+					 table_index);
+
+		dev_dbg(port->dev, "Set %s trans window[%d]: cpu_addr = %#llx, pci_addr = %#llx, size = %#llx\n",
+			(!!(type & IORESOURCE_MEM) ? "MEM" : "IO"), table_index,
+			cpu_addr, pci_addr, resource_size(res));
+
+		table_index++;
+	}
+
+	return 0;
+}
+
+static inline struct mtk_pcie_msi *mtk_get_msi_info(struct mtk_pcie_port *port,
+						    unsigned long hwirq)
+{
+	return port->msi_info[hwirq / PCIE_MSI_IRQS_PER_SET];
+}
+
+static int mtk_pcie_set_affinity(struct irq_data *data,
+				 const struct cpumask *mask, bool force)
+{
+	struct mtk_pcie_port *port = irq_data_get_irq_chip_data(data);
+	int ret;
+
+	ret = irq_set_affinity_hint(port->irq, mask);
+	if (ret)
+		return ret;
+
+	irq_data_update_effective_affinity(data, mask);
+
+	return 0;
+}
+
+static void mtk_compose_msi_msg(struct irq_data *data, struct msi_msg *msg)
+{
+	struct mtk_pcie_msi *msi_info;
+	struct mtk_pcie_port *port = irq_data_get_irq_chip_data(data);
+
+	msi_info = mtk_get_msi_info(port, data->hwirq);
+
+	msg->address_hi = 0;
+	msg->address_lo = lower_32_bits(msi_info->msg_addr);
+
+	msg->data = data->hwirq;
+	dev_dbg(port->dev, "msi#%#lx address_hi %#x address_lo %#x data %d\n",
+		data->hwirq, msg->address_hi, msg->address_lo, msg->data);
+}
+
+static void mtk_msi_irq_ack(struct irq_data *data)
+{
+	struct mtk_pcie_msi *msi_info;
+	struct mtk_pcie_port *port = irq_data_get_irq_chip_data(data);
+	unsigned long hwirq;
+
+	msi_info = mtk_get_msi_info(port, data->hwirq);
+
+	hwirq =	data->hwirq % PCIE_MSI_IRQS_PER_SET;
+
+	writel(1 << hwirq, msi_info->base + PCIE_MSI_STATUS_OFFSET);
+}
+
+static void mtk_msi_irq_mask(struct irq_data *data)
+{
+	struct mtk_pcie_msi *msi_info;
+	struct mtk_pcie_port *port = irq_data_get_irq_chip_data(data);
+	u32 val;
+
+	msi_info = mtk_get_msi_info(port, data->hwirq);
+	val = readl(msi_info->base + PCIE_MSI_ENABLE_OFFSET);
+	val &= ~(1 << data->hwirq);
+	writel(val, msi_info->base + PCIE_MSI_ENABLE_OFFSET);
+
+	pci_msi_mask_irq(data);
+}
+
+static void mtk_msi_irq_unmask(struct irq_data *data)
+{
+	struct mtk_pcie_msi *msi_info;
+	struct mtk_pcie_port *port = irq_data_get_irq_chip_data(data);
+	u32 val;
+
+	msi_info = mtk_get_msi_info(port, data->hwirq);
+	val = readl(msi_info->base + PCIE_MSI_ENABLE_OFFSET);
+	val |= (1 << data->hwirq);
+	writel(val, msi_info->base + PCIE_MSI_ENABLE_OFFSET);
+
+	pci_msi_unmask_irq(data);
+}
+
+static struct irq_chip mtk_msi_irq_chip = {
+	.irq_ack		= mtk_msi_irq_ack,
+	.irq_compose_msi_msg	= mtk_compose_msi_msg,
+	.irq_mask		= mtk_msi_irq_mask,
+	.irq_unmask		= mtk_msi_irq_unmask,
+	.irq_set_affinity	= mtk_pcie_set_affinity,
+	.name			= "PCIe",
+};
+
+static irq_hw_number_t mtk_pcie_msi_get_hwirq(struct msi_domain_info *info,
+					      msi_alloc_info_t *arg)
+{
+	struct msi_desc *entry = arg->desc;
+	struct mtk_pcie_port *port = info->chip_data;
+	int hwirq;
+
+	mutex_lock(&port->lock);
+
+	hwirq = bitmap_find_free_region(port->msi_irq_in_use, PCIE_MSI_IRQS_NUM,
+			order_base_2(entry->nvec_used));
+	if (hwirq < 0) {
+		mutex_unlock(&port->lock);
+		return -ENOSPC;
+	}
+
+	mutex_unlock(&port->lock);
+
+	return hwirq;
+}
+
+static void mtk_pcie_msi_free(struct irq_domain *domain,
+			      struct msi_domain_info *info, unsigned int virq)
+{
+	struct irq_data *data = irq_domain_get_irq_data(domain, virq);
+	struct mtk_pcie_port *port = irq_data_get_irq_chip_data(data);
+
+	mutex_lock(&port->lock);
+
+	bitmap_clear(port->msi_irq_in_use, data->hwirq, 1);
+
+	mutex_unlock(&port->lock);
+}
+
+static struct msi_domain_ops mtk_msi_domain_ops = {
+	.get_hwirq	= mtk_pcie_msi_get_hwirq,
+	.msi_free	= mtk_pcie_msi_free,
+};
+
+static struct msi_domain_info mtk_msi_domain_info = {
+	.flags		= (MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_PCI_MSIX |
+			   MSI_FLAG_USE_DEF_CHIP_OPS | MSI_FLAG_MULTI_PCI_MSI),
+	.chip		= &mtk_msi_irq_chip,
+	.ops		= &mtk_msi_domain_ops,
+	.handler	= handle_edge_irq,
+	.handler_name	= "MSI",
+};
+
+static void mtk_msi_top_irq_eoi(struct irq_data *data)
+{
+	struct mtk_pcie_port *port = irq_data_get_irq_chip_data(data);
+	unsigned long msi_irq = data->hwirq + PCIE_MSI_SHIFT;
+
+	writel(1 << msi_irq, port->base + PCIE_INT_STATUS_REG);
+}
+
+static struct irq_chip mtk_msi_top_irq_chip = {
+	.irq_eoi	= mtk_msi_top_irq_eoi,
+	.name		= "PCIe",
+};
+
+static void mtk_pcie_msi_handler(struct irq_desc *desc)
+{
+	struct mtk_pcie_msi *msi_info = irq_desc_get_handler_data(desc);
+	struct irq_chip *irqchip = irq_desc_get_chip(desc);
+	unsigned long msi_enable, msi_status;
+	unsigned int virq;
+	irq_hw_number_t bit, hwirq;
+
+	chained_irq_enter(irqchip, desc);
+
+	msi_enable = readl(msi_info->base + PCIE_MSI_ENABLE_OFFSET);
+	while ((msi_status = readl(msi_info->base + PCIE_MSI_STATUS_OFFSET))) {
+		msi_status &= msi_enable;
+		for_each_set_bit(bit, &msi_status, PCIE_MSI_IRQS_PER_SET) {
+			hwirq = bit + msi_info->index * PCIE_MSI_IRQS_PER_SET;
+			virq = irq_find_mapping(msi_info->domain, hwirq);
+			generic_handle_irq(virq);
+		}
+	}
+
+	chained_irq_exit(irqchip, desc);
+}
+
+static int mtk_msi_top_domain_map(struct irq_domain *domain,
+				    unsigned int virq, irq_hw_number_t hwirq)
+{
+	struct mtk_pcie_port *port = domain->host_data;
+	struct mtk_pcie_msi *msi_info = port->msi_info[hwirq];
+
+	irq_domain_set_info(domain, virq, hwirq,
+			    &mtk_msi_top_irq_chip, domain->host_data,
+			    mtk_pcie_msi_handler, msi_info, NULL);
+
+	return 0;
+}
+
+static const struct irq_domain_ops mtk_msi_top_domain_ops = {
+	.map = mtk_msi_top_domain_map,
+};
+
+static void mtk_intx_mask(struct irq_data *data)
+{
+	struct mtk_pcie_port *port = irq_data_get_irq_chip_data(data);
+	u32 val;
+
+	val = readl(port->base + PCIE_INT_ENABLE_REG);
+	val &= ~(1 << (data->hwirq + PCIE_INTX_SHIFT));
+	writel(val, port->base + PCIE_INT_ENABLE_REG);
+}
+
+static void mtk_intx_unmask(struct irq_data *data)
+{
+	struct mtk_pcie_port *port = irq_data_get_irq_chip_data(data);
+	u32 val;
+
+	val = readl(port->base + PCIE_INT_ENABLE_REG);
+	val |= 1 << (data->hwirq + PCIE_INTX_SHIFT);
+	writel(val, port->base + PCIE_INT_ENABLE_REG);
+}
+
+static void mtk_intx_eoi(struct irq_data *data)
+{
+	struct mtk_pcie_port *port = irq_data_get_irq_chip_data(data);
+	unsigned long hwirq;
+
+	/**
+	 * As an emulated level irq, its interrupt status will be remained
+	 * until receive the corresponding message of de-assert, hence that
+	 * the status can only be cleared when the interrupt has been serviced.
+	 */
+	hwirq = data->hwirq + PCIE_INTX_SHIFT;
+	writel(1 << hwirq, port->base + PCIE_INT_STATUS_REG);
+}
+
+static struct irq_chip mtk_intx_irq_chip = {
+	.irq_mask		= mtk_intx_mask,
+	.irq_unmask		= mtk_intx_unmask,
+	.irq_eoi		= mtk_intx_eoi,
+	.irq_set_affinity	= mtk_pcie_set_affinity,
+	.name			= "PCIe",
+};
+
+static int mtk_pcie_intx_map(struct irq_domain *domain, unsigned int irq,
+			     irq_hw_number_t hwirq)
+{
+	irq_set_chip_and_handler_name(irq, &mtk_intx_irq_chip,
+				      handle_fasteoi_irq, "INTx");
+	irq_set_chip_data(irq, domain->host_data);
+
+	return 0;
+}
+
+static const struct irq_domain_ops intx_domain_ops = {
+	.map = mtk_pcie_intx_map,
+};
+
+static int mtk_pcie_init_irq_domains(struct mtk_pcie_port *port,
+				     struct device_node *node)
+{
+	struct device *dev = port->dev;
+	struct device_node *intc_node;
+	struct fwnode_handle *fwnode = of_node_to_fwnode(node);
+	struct mtk_pcie_msi *msi_info;
+	struct msi_domain_info *info;
+	int i, ret;
+
+	/* Setup INTx */
+	intc_node = of_get_child_by_name(node, "interrupt-controller");
+	if (!intc_node) {
+		dev_notice(dev, "Missing PCIe Intc node\n");
+		return -ENODEV;
+	}
+
+	port->intx_domain = irq_domain_add_linear(intc_node, PCI_NUM_INTX,
+						  &intx_domain_ops, port);
+	if (!port->intx_domain) {
+		dev_notice(dev, "failed to get INTx IRQ domain\n");
+		return -ENODEV;
+	}
+
+	/* Setup MSI */
+	mutex_init(&port->lock);
+
+	info = devm_kzalloc(dev, sizeof(*info), GFP_KERNEL);
+	if (!info)
+		return -ENOMEM;
+
+	memcpy(info, &mtk_msi_domain_info, sizeof(*info));
+	info->chip_data = port;
+
+	port->msi_domain = pci_msi_create_irq_domain(fwnode, info, NULL);
+	if (!port->msi_domain) {
+		dev_info(dev, "failed to create msi domain\n");
+		ret = -ENODEV;
+		goto err_msi_domain;
+	}
+
+	/* Enable MSI and setup pcie domains */
+	port->msi_top_domain = irq_domain_add_hierarchy(NULL, 0, 0, node,
+							&mtk_msi_top_domain_ops,
+							port);
+	if (!port->msi_top_domain) {
+		dev_info(dev, "failed to create msi top domain\n");
+		ret = -ENODEV;
+		goto err_msi_top_domain;
+	}
+
+	port->msi_info = devm_kzalloc(dev, PCIE_MSI_SET_NUM, GFP_KERNEL);
+	if (!port->msi_info) {
+		ret = -ENOMEM;
+		goto err_msi_info;
+	}
+
+	for (i = 0; i < PCIE_MSI_SET_NUM; i++) {
+		int offset = i * PCIE_MSI_SET_OFFSET;
+		u32 val;
+
+		msi_info = devm_kzalloc(dev, sizeof(*msi_info), GFP_KERNEL);
+		if (!msi_info) {
+			ret = -ENOMEM;
+			goto err_msi_set;
+		}
+
+		msi_info->base = port->base + PCIE_MSI_ADDR_BASE_REG + offset;
+		msi_info->msg_addr = port->reg_base + PCIE_MSI_ADDR_BASE_REG +
+				     offset;
+
+		writel(lower_32_bits(msi_info->msg_addr), msi_info->base);
+
+		msi_info->index = i;
+		msi_info->domain = port->msi_domain;
+
+		port->msi_info[i] = msi_info;
+
+		/* Alloc irq for each msi set */
+		msi_info->irq = irq_create_mapping(port->msi_top_domain, i);
+		if (!msi_info->irq) {
+			dev_info(dev, "allocate msi top irq failed\n");
+			ret = -ENOSPC;
+			goto err_msi_set;
+		}
+
+		val = readl(port->base + PCIE_INT_ENABLE_REG);
+		val |= (1 << (i + PCIE_MSI_SHIFT));
+		writel(val, port->base + PCIE_INT_ENABLE_REG);
+
+		val = readl(port->base + PCIE_MSI_SET_ENABLE_REG);
+		val |= (1 << i);
+		writel(val, port->base + PCIE_MSI_SET_ENABLE_REG);
+	}
+
+	return 0;
+
+err_msi_set:
+	while (--i >= 0) {
+		msi_info = port->msi_info[i];
+		irq_dispose_mapping(msi_info->irq);
+	}
+err_msi_info:
+	irq_domain_remove(port->msi_top_domain);
+err_msi_top_domain:
+	irq_domain_remove(port->msi_domain);
+err_msi_domain:
+	irq_domain_remove(port->intx_domain);
+
+	return ret;
+}
+
+static void mtk_pcie_irq_teardown(struct mtk_pcie_port *port)
+{
+	struct mtk_pcie_msi *msi_info;
+	int i;
+
+	irq_set_chained_handler_and_data(port->irq, NULL, NULL);
+
+	if (port->intx_domain)
+		irq_domain_remove(port->intx_domain);
+
+	if (port->msi_domain)
+		irq_domain_remove(port->msi_domain);
+
+	if (port->msi_top_domain) {
+		for (i = 0; i < PCIE_MSI_SET_NUM; i++) {
+			msi_info = port->msi_info[i];
+			irq_dispose_mapping(msi_info->irq);
+		}
+
+		irq_domain_remove(port->msi_top_domain);
+	}
+
+	irq_dispose_mapping(port->irq);
+}
+
+static void mtk_pcie_irq_handler(struct irq_desc *desc)
+{
+	struct mtk_pcie_port *port = irq_desc_get_handler_data(desc);
+	struct irq_chip *irqchip = irq_desc_get_chip(desc);
+	unsigned long status;
+	unsigned int virq;
+	irq_hw_number_t irq_bit = PCIE_INTX_SHIFT;
+
+	chained_irq_enter(irqchip, desc);
+
+	status = readl(port->base + PCIE_INT_STATUS_REG);
+	if (status & PCIE_INTX_MASK) {
+		for_each_set_bit_from(irq_bit, &status, PCI_NUM_INTX +
+				      PCIE_INTX_SHIFT) {
+			virq = irq_find_mapping(port->intx_domain,
+						irq_bit - PCIE_INTX_SHIFT);
+			generic_handle_irq(virq);
+		}
+	}
+
+	if (status & PCIE_MSI_MASK) {
+		irq_bit = PCIE_MSI_SHIFT;
+		for_each_set_bit_from(irq_bit, &status, PCIE_MSI_SET_NUM +
+				      PCIE_MSI_SHIFT) {
+			virq = irq_find_mapping(port->msi_top_domain,
+						irq_bit - PCIE_MSI_SHIFT);
+			generic_handle_irq(virq);
+		}
+	}
+
+	chained_irq_exit(irqchip, desc);
+}
+
+static int mtk_pcie_setup_irq(struct mtk_pcie_port *port,
+			      struct device_node *node)
+{
+	struct device *dev = port->dev;
+	struct platform_device *pdev = to_platform_device(dev);
+	int err;
+
+	err = mtk_pcie_init_irq_domains(port, node);
+	if (err) {
+		dev_notice(dev, "failed to init PCIe IRQ domain\n");
+		return err;
+	}
+
+	port->irq = platform_get_irq(pdev, 0);
+	if (port->irq < 0)
+		return port->irq;
+
+	irq_set_chained_handler_and_data(port->irq, mtk_pcie_irq_handler, port);
+
+	return 0;
+}
+
+static int mtk_pcie_clk_init(struct mtk_pcie_port *port)
+{
+	int ret;
+
+	port->num_clks = devm_clk_bulk_get_all(port->dev, &port->clks);
+	if (port->num_clks < 0) {
+		dev_notice(port->dev, "failed to get pcie clock\n");
+		return port->num_clks;
+	}
+
+	ret = clk_bulk_prepare_enable(port->num_clks, port->clks);
+	if (ret) {
+		dev_notice(port->dev, "failed to enable pcie clocks\n");
+		return ret;
+	}
+
+	return 0;
+}
+
+static int mtk_pcie_power_up(struct mtk_pcie_port *port)
+{
+	struct device *dev = port->dev;
+	int err;
+
+	port->phy_reset = devm_reset_control_get_optional_exclusive(dev, "phy");
+	if (IS_ERR(port->phy_reset))
+		return PTR_ERR(port->phy_reset);
+
+	/* PHY power on and enable pipe clock */
+	port->phy = devm_phy_optional_get(dev, "pcie-phy");
+	if (IS_ERR(port->phy))
+		return PTR_ERR(port->phy);
+
+	reset_control_deassert(port->phy_reset);
+
+	err = phy_power_on(port->phy);
+	if (err) {
+		dev_notice(dev, "failed to power on pcie phy\n");
+		goto err_phy_on;
+	}
+
+	err = phy_init(port->phy);
+	if (err) {
+		dev_notice(dev, "failed to initialize pcie phy\n");
+		goto err_phy_init;
+	}
+
+	port->mac_reset = devm_reset_control_get_optional_exclusive(dev, "mac");
+	if (IS_ERR(port->mac_reset)) {
+		err = PTR_ERR(port->mac_reset);
+		goto err_mac_rst;
+	}
+
+	reset_control_deassert(port->mac_reset);
+
+	/* MAC power on and enable transaction layer clocks */
+	pm_runtime_enable(dev);
+	pm_runtime_get_sync(dev);
+
+	err = mtk_pcie_clk_init(port);
+	if (err) {
+		dev_notice(dev, "clock init failed\n");
+		goto err_clk_init;
+	}
+
+	return 0;
+
+err_clk_init:
+	pm_runtime_put_sync(dev);
+	pm_runtime_disable(dev);
+	reset_control_assert(port->mac_reset);
+err_mac_rst:
+	phy_exit(port->phy);
+err_phy_init:
+	phy_power_off(port->phy);
+err_phy_on:
+	reset_control_assert(port->phy_reset);
+
+	return err;
+}
+
+static void mtk_pcie_power_down(struct mtk_pcie_port *port)
+{
+	clk_bulk_disable_unprepare(port->num_clks, port->clks);
+
+	pm_runtime_put_sync(port->dev);
+	pm_runtime_disable(port->dev);
+	reset_control_assert(port->mac_reset);
+
+	phy_power_off(port->phy);
+	phy_exit(port->phy);
+	reset_control_assert(port->phy_reset);
+}
+
+static int mtk_pcie_setup(struct mtk_pcie_port *port)
+{
+	struct device *dev = port->dev;
+	struct platform_device *pdev = to_platform_device(dev);
+	struct resource *regs;
+	int err;
+
+	regs = platform_get_resource_byname(pdev, IORESOURCE_MEM, "pcie-mac");
+	port->base = devm_ioremap_resource(dev, regs);
+	if (IS_ERR(port->base)) {
+		dev_notice(dev, "failed to map register base\n");
+		return PTR_ERR(port->base);
+	}
+
+	port->reg_base = regs->start;
+
+	/* Don't touch the hardware registers before power up */
+	err = mtk_pcie_power_up(port);
+	if (err)
+		return err;
+
+	/* Try link up */
+	err = mtk_pcie_startup_port(port);
+	if (err) {
+		dev_notice(dev, "PCIe link down\n");
+		goto err_setup;
+	}
+
+	err = mtk_pcie_setup_irq(port, dev->of_node);
+	if (err)
+		goto err_setup;
+
+	dev_info(dev, "PCIe link up success!\n");
+
+	return 0;
+
+err_setup:
+	mtk_pcie_power_down(port);
+
+	return err;
+}
+
+static int mtk_pcie_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct mtk_pcie_port *port;
+	struct pci_host_bridge *host;
+	int err;
+
+	host = devm_pci_alloc_host_bridge(dev, sizeof(*port));
+	if (!host)
+		return -ENOMEM;
+
+	port = pci_host_bridge_priv(host);
+
+	port->dev = dev;
+	platform_set_drvdata(pdev, port);
+
+	err = mtk_pcie_setup(port);
+	if (err)
+		return err;
+
+	host->ops = &mtk_pcie_ops;
+	host->sysdata = port;
+
+	err = pci_host_probe(host);
+	if (err) {
+		mtk_pcie_power_down(port);
+		return err;
+	}
+
+	return 0;
+}
+
+static int mtk_pcie_remove(struct platform_device *pdev)
+{
+	struct mtk_pcie_port *port = platform_get_drvdata(pdev);
+	struct pci_host_bridge *host = pci_host_bridge_from_priv(port);
+
+	pci_lock_rescan_remove();
+	pci_stop_root_bus(host->bus);
+	pci_remove_root_bus(host->bus);
+	pci_unlock_rescan_remove();
+
+	mtk_pcie_irq_teardown(port);
+	mtk_pcie_power_down(port);
+
+	return 0;
+}
+
+static int __maybe_unused mtk_pcie_turn_off_link(struct mtk_pcie_port *port)
+{
+	u32 val;
+
+	val = readl(port->base + PCIE_ICMD_PM_REG);
+	val |= PCIE_TURN_OFF_LINK;
+	writel(val, port->base + PCIE_ICMD_PM_REG);
+
+	/* Check the link is L2 */
+	return readl_poll_timeout(port->base + PCIE_LTSSM_STATUS_REG, val,
+				  (PCIE_LTSSM_STATE(val) ==
+				   PCIE_LTSSM_STATE_L2_IDLE), 20,
+				   50 * USEC_PER_MSEC);
+}
+
+static int __maybe_unused mtk_pcie_suspend_noirq(struct device *dev)
+{
+	struct mtk_pcie_port *port = dev_get_drvdata(dev);
+	int err;
+	u32 val;
+
+	if (port->is_suspended)
+		return 0;
+
+	/* Trigger link to L2 state */
+	err = mtk_pcie_turn_off_link(port);
+	if (err) {
+		dev_notice(port->dev, "can not enter L2 state\n");
+		goto power_off;
+	}
+
+	/* Pull down the PERST# pin */
+	val = readl(port->base + PCIE_RST_CTRL_REG);
+	val |= PCIE_PE_RSTB;
+	writel(val, port->base + PCIE_RST_CTRL_REG);
+
+	dev_info(port->dev, "enter L2 state success");
+
+power_off:
+	clk_bulk_disable_unprepare(port->num_clks, port->clks);
+
+	phy_power_off(port->phy);
+
+	port->is_suspended = true;
+
+	return 0;
+}
+
+static int __maybe_unused mtk_pcie_resume_noirq(struct device *dev)
+{
+	struct mtk_pcie_port *port = dev_get_drvdata(dev);
+	int err;
+
+	if (!port->is_suspended)
+		return 0;
+
+	phy_power_on(port->phy);
+
+	err = clk_bulk_prepare_enable(port->num_clks, port->clks);
+	if (err) {
+		dev_dbg(dev, "failed to enable pcie clocks\n");
+		return err;
+	}
+
+	err = mtk_pcie_startup_port(port);
+	if (err) {
+		dev_notice(port->dev, "resume failed\n");
+		return err;
+	}
+
+	port->is_suspended = false;
+
+	dev_info(port->dev, "resume done\n");
+
+	return 0;
+}
+
+static const struct dev_pm_ops mtk_pcie_pm_ops = {
+	SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(mtk_pcie_suspend_noirq,
+				      mtk_pcie_resume_noirq)
+};
+
+static const struct of_device_id mtk_pcie_of_match[] = {
+	{ .compatible = "mediatek,mt8192-pcie" },
+	{},
+};
+
+static struct platform_driver mtk_pcie_driver = {
+	.probe = mtk_pcie_probe,
+	.remove = mtk_pcie_remove,
+	.driver = {
+		.name = "mtk-pcie",
+		.of_match_table = mtk_pcie_of_match,
+		.pm = &mtk_pcie_pm_ops,
+	},
+};
+
+module_platform_driver(mtk_pcie_driver);
+MODULE_LICENSE("GPL v2");
-- 
2.25.1

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