From 29ceb2449cb3622ccfba9eb1c77bf2ac4162464b Mon Sep 17 00:00:00 2001
From: John Crispin <blogic@openwrt.org>
Date: Sat, 27 Jun 2015 13:15:29 +0200
Subject: [PATCH 64/76] arm: mediatek: add mt7623 pcie support

Signed-off-by: John Crispin <blogic@openwrt.org>
---
 arch/arm/mach-mediatek/Makefile |    2 +-
 arch/arm/mach-mediatek/pcie.c   |  383 +++++++++++++++++++++++++++++++++++++++
 arch/arm/mach-mediatek/pcie.h   |   14 ++
 3 files changed, 398 insertions(+), 1 deletion(-)
 create mode 100644 arch/arm/mach-mediatek/pcie.c
 create mode 100644 arch/arm/mach-mediatek/pcie.h

--- a/arch/arm/mach-mediatek/Makefile
+++ b/arch/arm/mach-mediatek/Makefile
@@ -1,4 +1,4 @@
 ifeq ($(CONFIG_SMP),y)
 obj-$(CONFIG_ARCH_MEDIATEK) += platsmp.o
 endif
-obj-$(CONFIG_ARCH_MEDIATEK) += mediatek.o
+obj-$(CONFIG_ARCH_MEDIATEK) += mediatek.o pcie.o
--- /dev/null
+++ b/arch/arm/mach-mediatek/pcie.c
@@ -0,0 +1,383 @@
+/*
+ *  Mediatek MT7623 SoC PCIE support
+ *
+ *  Copyright (C) 2015 Mediatek
+ *  Copyright (C) 2015 John Crispin <blogic@openwrt.org>
+ *
+ *  This program is free software; you can redistribute it and/or modify it
+ *  under the terms of the GNU General Public License version 2 as published
+ *  by the Free Software Foundation.
+ */
+
+#include <linux/kernel.h>
+#include <linux/pci.h>
+#include <linux/ioport.h>
+#include <linux/interrupt.h>
+#include <linux/spinlock.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/delay.h>
+#include <asm/irq.h>
+#include <asm/mach/pci.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_irq.h>
+#include <linux/of_pci.h>
+#include <linux/reset.h>
+#include <linux/platform_device.h>
+
+#include "pcie.h"
+
+#define PCICFG			0x00
+#define PCIINT			0x08
+#define PCIENA			0x0C
+#define CFGADDR			0x20
+#define CFGDATA			0x24
+#define MEMBASE			0x28
+#define IOBASE			0x2C
+
+#define BAR0SETUP		0x10
+#define IMBASEBAR0		0x18
+#define PCIE_CLASS		0x34
+#define PCIE_SISTAT		0x50
+
+#define MTK_PCIE_HIGH_PERF	BIT(14)
+#define PCIEP0_BASE		0x2000
+#define PCIEP1_BASE		0x3000
+#define PCIEP2_BASE		0x4000
+
+#define PHY_P0_CTL		0x9000
+#define PHY_P1_CTL		0xA000
+#define PHY_P2_CTL		0x4000
+
+#define RSTCTL_PCIE0_RST	BIT(24)
+#define RSTCTL_PCIE1_RST	BIT(25)
+#define RSTCTL_PCIE2_RST	BIT(26)
+
+static void __iomem *pcie_base;
+static int pcie_card_link;
+
+static struct mtk_pcie_port {
+	int id;
+	int enable;
+	u32 base;
+	u32 phy_base;
+	u32 perst_n;
+	u32 reset;
+	u32 interrupt;
+	u32 link;
+} mtk_pcie_port[] = {
+	{ 0, 1, PCIEP0_BASE, PHY_P0_CTL, BIT(1), RSTCTL_PCIE0_RST, BIT(20) },
+	{ 1, 1, PCIEP1_BASE, PHY_P1_CTL, BIT(2), RSTCTL_PCIE1_RST, BIT(21) },
+	{ 2, 0, PCIEP2_BASE, PHY_P2_CTL, BIT(3), RSTCTL_PCIE2_RST, BIT(22) },
+};
+
+#define mtk_foreach_port(p)		\
+	for (p = mtk_pcie_port; p != &mtk_pcie_port[ARRAY_SIZE(mtk_pcie_port)]; p++)
+
+#define mtk_foreach_port_enabled(p)	\
+	mtk_foreach_port(p)		\
+		if (p->enable)
+
+#define mtk_foreach_port_link(p)	\
+	mtk_foreach_port(p)		\
+		if (p->link)
+
+static struct mtk_phy_init {
+	uint32_t reg;
+	uint32_t mask;
+	uint32_t val;
+} mtk_phy_init[] = {
+	{ 0xC00, 0x33000, 0x22000 },
+	{ 0xB04, 0xe0000000, 0x40000000 },
+	{ 0xB00, 0xe, 0x4 },
+	{ 0xC3C, 0xffff0000, 0x3c0000 },
+	{ 0xC48, 0xffff, 0x36 },
+	{ 0xC0C, 0x30000000, 0x10000000 },
+	{ 0xC08, 0x3800c0, 0xc0 },
+	{ 0xC10, 0xf0000, 0x20000 },
+	{ 0xC0C, 0xf000, 0x1000 },
+	{ 0xC14, 0xf0000, 0xa0000 },
+};
+
+static inline void pcie_w32(u32 val, unsigned reg)
+{
+	iowrite32(val, pcie_base + reg);
+}
+
+static inline u32 pcie_r32(unsigned reg)
+{
+	return ioread32(pcie_base + reg);
+}
+
+static inline void pcie_m32(u32 mask, u32 val, unsigned reg)
+{
+	u32 v = pcie_r32(reg);
+
+	v &= mask;
+	v |= val;
+	pcie_w32(v, reg);
+}
+
+static int pcie_config_read(struct pci_bus *bus, unsigned int devfn, int where, int size, u32 * val)
+{
+	unsigned int slot = PCI_SLOT(devfn);
+	u8 func = PCI_FUNC(devfn);
+	u32 address;
+	u32 data;
+	u32 num = 0;
+
+	if (bus)
+		num = bus->number;
+
+	address = (((where & 0xF00) >> 8) << 24) | (num << 16) | (slot << 11) | (func << 8) | (where & 0xfc);
+	pcie_m32(0xf0000000, address, CFGADDR);
+	data = pcie_r32(CFGDATA);
+
+	switch (size) {
+	case 1:
+		*val = (data >> ((where & 3) << 3)) & 0xff;
+		break;
+	case 2:
+		*val = (data >> ((where & 3) << 3)) & 0xffff;
+		break;
+	case 4:
+		*val = data;
+		break;
+	}
+
+	return PCIBIOS_SUCCESSFUL;
+}
+
+static int pcie_config_write(struct pci_bus *bus, unsigned int devfn, int where, int size, u32 val)
+{
+	unsigned int slot = PCI_SLOT(devfn);
+	u8 func = PCI_FUNC(devfn);
+	u32 address;
+	u32 data;
+	u32 num = 0;
+
+	if (bus)
+		num = bus->number;
+
+	address = (((where & 0xF00) >> 8) << 24) | (num << 16) | (slot << 11) | (func << 8) | (where & 0xfc);
+	pcie_m32(0xf0000000, address, CFGADDR);
+	data = pcie_r32(CFGDATA);
+
+	switch (size) {
+	case 1:
+		data = (data & ~(0xff << ((where & 3) << 3))) |
+		(val << ((where & 3) << 3));
+		break;
+	case 2:
+		data = (data & ~(0xffff << ((where & 3) << 3))) |
+		(val << ((where & 3) << 3));
+		break;
+	case 4:
+		data = val;
+		break;
+	}
+
+	pcie_w32(data, CFGDATA);
+
+	return PCIBIOS_SUCCESSFUL;
+}
+
+static struct pci_ops mtk_pcie_ops = {
+	.read   = pcie_config_read,
+	.write  = pcie_config_write,
+};
+
+static struct resource pci_mem = {
+	.name   = "PCIe Memory space",
+	.start  = MEM_DIRECT1,
+	.end    = (u32) (MEM_DIRECT1 + (unsigned char *) 0x0fffffff),
+	.flags  = IORESOURCE_MEM,
+};
+
+static struct resource pci_io = {
+	.name   = "PCIe IO space",
+	.start  = IO_WIN,
+	.end    = (u32) (IO_WIN + (unsigned char *) 0x0ffff),
+	.flags  = IORESOURCE_IO,
+};
+
+static int __init mtk_pcie_setup(int nr, struct pci_sys_data *sys)
+{
+	sys->mem_offset = 0;
+	sys->io_offset = 0;
+
+	request_resource(&ioport_resource, &pci_io);
+	request_resource(&iomem_resource, &pci_mem);
+
+	pci_add_resource_offset(&sys->resources, &pci_io, sys->io_offset);
+	pci_add_resource_offset(&sys->resources, &pci_mem, sys->mem_offset);
+
+	return 1;
+}
+
+static struct pci_bus * __init mtk_pcie_scan_bus(int nr, struct pci_sys_data *sys)
+{
+	return pci_scan_root_bus(NULL, sys->busnr, &mtk_pcie_ops, sys,
+				 &sys->resources);
+}
+
+static int __init mtk_pcie_map_irq(const struct pci_dev *dev, u8 slot, u8 pin)
+{
+	u16 cmd;
+	u32 val;
+
+	if (dev->bus->number == 0) {
+		pcie_config_write(NULL, slot, 0, PCI_BASE_ADDRESS_0, MEMORY_BASE);
+		pcie_config_read(NULL, slot, 0, PCI_BASE_ADDRESS_0, &val);
+		printk("BAR0 at bus %d, slot %d\n", dev->bus->number, slot);
+	}
+
+	printk("bus=0x%x, slot = 0x%x, pin=0x%x, irq=0x%x\n", dev->bus->number, slot, pin, dev->irq);
+
+	pci_write_config_byte(dev, PCI_CACHE_LINE_SIZE, 0x14);
+	pci_write_config_byte(dev, PCI_LATENCY_TIMER, 0xFF);
+	pci_read_config_word(dev, PCI_COMMAND, &cmd);
+	cmd = cmd | PCI_COMMAND_MASTER | PCI_COMMAND_IO | PCI_COMMAND_MEMORY;
+	pci_write_config_word(dev, PCI_COMMAND, cmd);
+	pci_write_config_byte(dev, PCI_INTERRUPT_LINE, dev->irq);
+
+	return dev->irq;
+}
+
+static void __init mtk_pcie_preinit(void)
+{
+	struct mtk_pcie_port *port;
+	u32 val = 0;
+	int i;
+
+	pcibios_min_io = 0;
+	pcibios_min_mem = 0;
+
+#if defined (CONFIG_PCIE_PORT2)
+	printk("%s: PCIe/USB3 combo PHY mode (%x) =%x\n", __func__, SYSCFG1, REGDATA(SYSCFG1));
+	REGDATA(SYSCFG1) &= ~(0x300000);
+	printk("%s: PCIe/USB3 combo PHY mode (%x) =%x\n", __func__, SYSCFG1, REGDATA(SYSCFG1));
+#endif
+
+	/* PCIe RC Reset */
+	val = 0;
+	mtk_foreach_port_enabled(port)
+		val |= port->reset;
+	REGDATA(RSTCTL) |= val;
+	mdelay(10);
+	REGDATA(RSTCTL) &= ~val;
+	mdelay(10);
+
+	/* Configure PCIe PHY */
+	mtk_foreach_port_enabled(port) {
+		for (i = 0; i < ARRAY_SIZE(mtk_phy_init); i++) {
+			u32 val = pcie_r32(port->phy_base + mtk_phy_init[i].reg);
+			val &= ~mtk_phy_init[i].mask;
+			val |= mtk_phy_init[i].val;
+			pcie_w32(val, port->phy_base + mtk_phy_init[i].reg);
+		}
+		mdelay(10);
+	}
+
+	/* Enable RC */
+	mtk_foreach_port_enabled(port) {
+		val = 0;
+		pcie_config_read(NULL, port->id, 0, 0x73c, &val);
+		val &= ~(0x9fff)<<16;
+		val |= 0x806c<<16;
+		pcie_config_write(NULL, port->id, 0, 0x73c, val);
+	}
+
+	/* PCIe EP reset */
+	val = 0;
+	mtk_foreach_port_enabled(port)
+		val |= port->perst_n;
+	val |= MTK_PCIE_HIGH_PERF;
+	pcie_w32(pcie_r32(PCICFG) | val, PCICFG);
+	mdelay(10);
+	pcie_w32(pcie_r32(PCICFG) & ~val, PCICFG);
+	mdelay(10);
+
+	/* check the link status */
+	val = 0;
+	mtk_foreach_port_enabled(port) {
+		if ((pcie_r32(port->base + PCIE_SISTAT) & 0x1))
+			port->link = 1;
+		else
+			val |= port->reset;
+	}
+	REGDATA(RSTCTL) |= val;
+
+	mtk_foreach_port_link(port)
+		pcie_card_link++;
+
+	printk("PCIe Link count = %d\n", pcie_card_link);
+	if (!pcie_card_link)
+		return;
+
+	pcie_w32(MEM_WIN, MEMBASE);
+	pcie_w32(IO_WIN, IOBASE);
+
+	mtk_foreach_port_link(port) {
+		pcie_m32(0, port->interrupt, PCIENA);
+		pcie_w32(0x7FFF0001, port->base + BAR0SETUP);
+		pcie_w32(MEMORY_BASE, port->base + IMBASEBAR0);
+		pcie_w32(0x06040001, port->base + PCIE_CLASS);
+		printk("PCIE%d Setup OK\n", port->id);
+	}
+	val = 0;
+
+	pcie_config_read(NULL, pcie_card_link - 1, 0, 0x4, &val);
+	pcie_config_write(NULL, pcie_card_link - 1, 0, 0x4, val|0x4);
+	pcie_config_read(NULL, pcie_card_link - 1, 0, 0x70c, &val);
+	val &= ~(0xff3) << 8;
+	val |= 0x50 << 8;
+	pcie_config_write(NULL, pcie_card_link - 1, 0, 0x70c, val);
+	pcie_config_read(NULL, pcie_card_link - 1, 0, 0x70c, &val);
+}
+
+static struct hw_pci mtk_pci __initdata = {
+	.nr_controllers		= 1,
+	.map_irq		= mtk_pcie_map_irq,
+	.setup			= mtk_pcie_setup,
+	.scan			= mtk_pcie_scan_bus,
+	.preinit		= mtk_pcie_preinit,
+};
+
+extern void mt7623_ethifsys_init(void);
+static int mtk_pcie_probe(struct platform_device *pdev)
+{
+	struct resource *pcie_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+
+	pcie_base = devm_ioremap_resource(&pdev->dev, pcie_res);
+        if (!pcie_base)
+		return -ENOMEM;
+
+	mt7623_ethifsys_init();
+	pci_common_init_dev(&pdev->dev, &mtk_pci);
+
+	return 0;
+}
+
+static const struct of_device_id mtk_pcie_ids[] = {
+	{ .compatible = "mediatek,mt7623-pcie" },
+	{},
+};
+MODULE_DEVICE_TABLE(of, mtk_pcie_ids);
+
+static struct platform_driver mtk_pcie_driver = {
+	.probe = mtk_pcie_probe,
+	.driver = {
+		.name = "mt7623-pcie",
+		.owner = THIS_MODULE,
+		.of_match_table = of_match_ptr(mtk_pcie_ids),
+	},
+};
+
+static int __init mtk_pcie_init(void)
+{
+	return platform_driver_register(&mtk_pcie_driver);
+}
+
+late_initcall(mtk_pcie_init);
--- /dev/null
+++ b/arch/arm/mach-mediatek/pcie.h
@@ -0,0 +1,14 @@
+#define SYSCTL_BASE	0xFA000000
+#define MEM_WIN		0x1A150000
+#define IO_WIN		0x1A160000
+#define MEM_DIRECT1	0x60000000
+#define MEMORY_BASE	0x80000000
+
+#define REGADDR(x, y)	(x##_BASE + y)
+#define REGDATA(x)			*((volatile unsigned int *)(x))	
+
+#define SYSCFG1		REGADDR(SYSCTL, 0x14)
+#define RSTCTL		REGADDR(SYSCTL, 0x34)
+
+
+