From 41aa7fc236fdb1f4c9b8b10df9b71f0d248cb36b Mon Sep 17 00:00:00 2001
From: John Crispin <blogic@openwrt.org>
Date: Mon, 7 Dec 2015 17:11:12 +0100
Subject: [PATCH 09/53] PCI: MIPS: adds mt7620a pcie driver

Signed-off-by: John Crispin <blogic@openwrt.org>
---
 arch/mips/include/asm/mach-ralink/mt7620.h |    1 +
 arch/mips/pci/Makefile                     |    1 +
 arch/mips/pci/pci-mt7620.c                 |  396 ++++++++++++++++++++++++++++
 arch/mips/ralink/Kconfig                   |    1 +
 4 files changed, 399 insertions(+)
 create mode 100644 arch/mips/pci/pci-mt7620.c

--- a/arch/mips/pci/Makefile
+++ b/arch/mips/pci/Makefile
@@ -43,6 +43,7 @@ obj-$(CONFIG_SIBYTE_BCM1x80)	+= pci-bcm1
 obj-$(CONFIG_SNI_RM)		+= fixup-sni.o ops-sni.o
 obj-$(CONFIG_LANTIQ)		+= fixup-lantiq.o
 obj-$(CONFIG_PCI_LANTIQ)	+= pci-lantiq.o ops-lantiq.o
+obj-$(CONFIG_SOC_MT7620)	+= pci-mt7620.o
 obj-$(CONFIG_SOC_MT7621)	+= pci-mt7621.o
 obj-$(CONFIG_SOC_RT288X)	+= pci-rt2880.o
 obj-$(CONFIG_SOC_RT3883)	+= pci-rt3883.o
--- /dev/null
+++ b/arch/mips/pci/pci-mt7620.c
@@ -0,0 +1,396 @@
+/*
+ *  Ralink MT7620A SoC PCI support
+ *
+ *  Copyright (C) 2007-2013 Bruce Chang
+ *  Copyright (C) 2013 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/types.h>
+#include <linux/pci.h>
+#include <linux/io.h>
+#include <linux/init.h>
+#include <linux/delay.h>
+#include <linux/interrupt.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 <asm/mach-ralink/ralink_regs.h>
+#include <asm/mach-ralink/mt7620.h>
+
+#define RALINK_PCI_MM_MAP_BASE		0x20000000
+#define RALINK_PCI_IO_MAP_BASE		0x10160000
+
+#define RALINK_INT_PCIE0		4
+#define RALINK_SYSCFG1			0x14
+#define RALINK_CLKCFG1			0x30
+#define RALINK_GPIOMODE			0x60
+#define RALINK_PCIE_CLK_GEN		0x7c
+#define RALINK_PCIE_CLK_GEN1		0x80
+#define PCIEPHY0_CFG			0x90
+#define PPLL_CFG1			0x9c
+#define PPLL_DRV			0xa0
+#define PDRV_SW_SET			(1<<31)
+#define LC_CKDRVPD_			(1<<19)
+
+#define RALINK_PCI_CONFIG_ADDR		0x20
+#define RALINK_PCI_CONFIG_DATA_VIRT_REG	0x24
+#define MEMORY_BASE			0x0
+#define RALINK_PCIE0_RST		(1<<26)
+#define RALINK_PCI_BASE			0xB0140000
+#define RALINK_PCI_MEMBASE		0x28
+#define RALINK_PCI_IOBASE		0x2C
+
+#define RT6855_PCIE0_OFFSET		0x2000
+
+#define RALINK_PCI_PCICFG_ADDR		0x00
+#define RALINK_PCI0_BAR0SETUP_ADDR	0x10
+#define RALINK_PCI0_IMBASEBAR0_ADDR	0x18
+#define RALINK_PCI0_ID			0x30
+#define RALINK_PCI0_CLASS		0x34
+#define RALINK_PCI0_SUBID		0x38
+#define RALINK_PCI0_STATUS		0x50
+#define RALINK_PCI_PCIMSK_ADDR		0x0C
+
+#define RALINK_PCIEPHY_P0_CTL_OFFSET	0x7498
+#define RALINK_PCIE0_CLK_EN		(1 << 26)
+
+#define BUSY				0x80000000
+#define WAITRETRY_MAX			10
+#define WRITE_MODE			(1UL << 23)
+#define DATA_SHIFT			0
+#define ADDR_SHIFT			8
+
+static void __iomem *bridge_base;
+static void __iomem *pcie_base;
+
+static struct reset_control *rstpcie0;
+
+static inline void bridge_w32(u32 val, unsigned reg)
+{
+	iowrite32(val, bridge_base + reg);
+}
+
+static inline u32 bridge_r32(unsigned reg)
+{
+	return ioread32(bridge_base + reg);
+}
+
+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 clr, u32 set, unsigned reg)
+{
+	u32 val = pcie_r32(reg);
+
+	val &= ~clr;
+	val |= set;
+	pcie_w32(val, reg);
+}
+
+static int wait_pciephy_busy(void)
+{
+	unsigned long reg_value = 0x0, retry = 0;
+
+	while (1) {
+		reg_value = pcie_r32(PCIEPHY0_CFG);
+
+		if (reg_value & BUSY)
+			mdelay(100);
+		else
+			break;
+		if (retry++ > WAITRETRY_MAX){
+			printk("PCIE-PHY retry failed.\n");
+			return -1;
+		}
+	}
+	return 0;
+}
+
+static void pcie_phy(unsigned long addr, unsigned long val)
+{
+	wait_pciephy_busy();
+	pcie_w32(WRITE_MODE | (val << DATA_SHIFT) | (addr << ADDR_SHIFT), PCIEPHY0_CFG);
+	mdelay(1);
+	wait_pciephy_busy();
+}
+
+static int pci_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) | 0x80000000;
+	bridge_w32(address, RALINK_PCI_CONFIG_ADDR);
+	data = bridge_r32(RALINK_PCI_CONFIG_DATA_VIRT_REG);
+
+	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 pci_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) | 0x80000000;
+	bridge_w32(address, RALINK_PCI_CONFIG_ADDR);
+	data = bridge_r32(RALINK_PCI_CONFIG_DATA_VIRT_REG);
+
+	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;
+	}
+
+	bridge_w32(data, RALINK_PCI_CONFIG_DATA_VIRT_REG);
+
+	return PCIBIOS_SUCCESSFUL;
+}
+
+struct pci_ops mt7620_pci_ops= {
+	.read	= pci_config_read,
+	.write	= pci_config_write,
+};
+
+static struct resource mt7620_res_pci_mem1;
+static struct resource mt7620_res_pci_io1;
+struct pci_controller mt7620_controller = {
+	.pci_ops	= &mt7620_pci_ops,
+	.mem_resource	= &mt7620_res_pci_mem1,
+	.mem_offset	= 0x00000000UL,
+	.io_resource	= &mt7620_res_pci_io1,
+	.io_offset	= 0x00000000UL,
+	.io_map_base	= 0xa0000000,
+};
+
+static int mt7620_pci_hw_init(struct platform_device *pdev) {
+	/* PCIE: bypass PCIe DLL */
+	pcie_phy(0x0, 0x80);
+	pcie_phy(0x1, 0x04);
+
+	/* PCIE: Elastic buffer control */
+	pcie_phy(0x68, 0xB4);
+
+	pcie_m32(0, BIT(1), RALINK_PCI_PCICFG_ADDR);
+
+	reset_control_assert(rstpcie0);
+
+	rt_sysc_m32(RALINK_PCIE0_CLK_EN, 0, RALINK_CLKCFG1);
+	rt_sysc_m32(BIT(19), BIT(31), PPLL_DRV);
+
+	reset_control_deassert(rstpcie0);
+	rt_sysc_m32(0, RALINK_PCIE0_CLK_EN, RALINK_CLKCFG1);
+
+	mdelay(100);
+
+	if (!(rt_sysc_r32(PPLL_CFG1) & BIT(23))) {
+		dev_err(&pdev->dev, "MT7620 PPLL unlock\n");
+		reset_control_assert(rstpcie0);
+		rt_sysc_m32(RALINK_PCIE0_CLK_EN, 0, RALINK_CLKCFG1);
+		return -1;
+	}
+	rt_sysc_m32(BIT(18) | BIT(17), BIT(19) | BIT(31), PPLL_DRV);
+
+	return 0;
+}
+
+static int mt7628_pci_hw_init(struct platform_device *pdev) {
+	u32 val = 0;
+
+	rt_sysc_m32(BIT(16), 0, RALINK_GPIOMODE);
+	reset_control_deassert(rstpcie0);
+	rt_sysc_m32(0, RALINK_PCIE0_CLK_EN, RALINK_CLKCFG1);
+	mdelay(100);
+
+	pcie_m32(~0xff, 0x5, RALINK_PCIEPHY_P0_CTL_OFFSET);
+
+	pci_config_read(NULL, 0, 0x70c, 4, &val);
+	val &= ~(0xff) << 8;
+	val |= 0x50 << 8;
+	pci_config_write(NULL, 0, 0x70c, 4, val);
+
+	pci_config_read(NULL, 0, 0x70c, 4, &val);
+	dev_err(&pdev->dev, "Port 0 N_FTS = %x\n", (unsigned int) val);
+
+	return 0;
+}
+
+static int mt7620_pci_probe(struct platform_device *pdev)
+{
+	struct resource *bridge_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	struct resource *pcie_res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+	u32 val = 0;
+
+	rstpcie0 = devm_reset_control_get(&pdev->dev, "pcie0");
+	if (IS_ERR(rstpcie0))
+		return PTR_ERR(rstpcie0);
+
+	bridge_base = devm_ioremap_resource(&pdev->dev, bridge_res);
+        if (!bridge_base)
+		return -ENOMEM;
+
+	pcie_base = devm_ioremap_resource(&pdev->dev, pcie_res);
+        if (!pcie_base)
+		return -ENOMEM;
+
+	iomem_resource.start = 0;
+	iomem_resource.end = ~0;
+	ioport_resource.start = 0;
+	ioport_resource.end = ~0;
+
+	/* bring up the pci core */
+	switch (ralink_soc) {
+	case MT762X_SOC_MT7620A:
+		if (mt7620_pci_hw_init(pdev))
+			return -1;
+		break;
+
+	case MT762X_SOC_MT7628AN:
+		if (mt7628_pci_hw_init(pdev))
+			return -1;
+		break;
+
+	default:
+		dev_err(&pdev->dev, "pcie is not supported on this hardware\n");
+		return -1;
+	}
+	mdelay(50);
+
+	/* enable write access */
+	pcie_m32(BIT(1), 0, RALINK_PCI_PCICFG_ADDR);
+	mdelay(100);
+
+	/* check if there is a card present */
+	if ((pcie_r32(RALINK_PCI0_STATUS) & 0x1) == 0) {
+		reset_control_assert(rstpcie0);
+		rt_sysc_m32(RALINK_PCIE0_CLK_EN, 0, RALINK_CLKCFG1);
+		if (ralink_soc == MT762X_SOC_MT7620A)
+			rt_sysc_m32(LC_CKDRVPD_, PDRV_SW_SET, PPLL_DRV);
+		dev_err(&pdev->dev, "PCIE0 no card, disable it(RST&CLK)\n");
+		return -1;
+	}
+
+	/* setup ranges */
+	bridge_w32(0xffffffff, RALINK_PCI_MEMBASE);
+	bridge_w32(RALINK_PCI_IO_MAP_BASE, RALINK_PCI_IOBASE);
+
+	pcie_w32(0x7FFF0001, RALINK_PCI0_BAR0SETUP_ADDR);
+	pcie_w32(MEMORY_BASE, RALINK_PCI0_IMBASEBAR0_ADDR);
+	pcie_w32(0x06040001, RALINK_PCI0_CLASS);
+
+	/* enable interrupts */
+	pcie_m32(0, BIT(20), RALINK_PCI_PCIMSK_ADDR);
+
+	/* voodoo from the SDK driver */
+	pci_config_read(NULL, 0, 4, 4, &val);
+	pci_config_write(NULL, 0, 4, 4, val | 0x7);
+
+	pci_load_of_ranges(&mt7620_controller, pdev->dev.of_node);
+	register_pci_controller(&mt7620_controller);
+
+	return 0;
+}
+
+int __init pcibios_map_irq(const struct pci_dev *dev, u8 slot, u8 pin)
+{
+	u16 cmd;
+	u32 val;
+	int irq = 0;
+
+	if ((dev->bus->number == 0) && (slot == 0)) {
+		pcie_w32(0x7FFF0001, RALINK_PCI0_BAR0SETUP_ADDR); //open 7FFF:2G; ENABLE
+		pci_config_write(dev->bus, 0, PCI_BASE_ADDRESS_0, 4, MEMORY_BASE);
+		pci_config_read(dev->bus, 0, PCI_BASE_ADDRESS_0, 4, &val);
+	} else if ((dev->bus->number == 1) && (slot == 0x0)) {
+		irq = RALINK_INT_PCIE0;
+	} else {
+		dev_err(&dev->dev, "no irq found - bus=0x%x, slot = 0x%x\n", dev->bus->number, slot);
+		return 0;
+	}
+	dev_err(&dev->dev, "card - bus=0x%x, slot = 0x%x irq=%d\n", dev->bus->number, slot, irq);
+
+	pci_write_config_byte(dev, PCI_CACHE_LINE_SIZE, 0x14);  //configure cache line size 0x14
+	pci_write_config_byte(dev, PCI_LATENCY_TIMER, 0xFF);  //configure latency timer 0x10
+	pci_read_config_word(dev, PCI_COMMAND, &cmd);
+
+	// FIXME
+	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);
+	//pci_write_config_byte(dev, PCI_INTERRUPT_PIN, dev->irq);
+
+	return irq;
+}
+
+int pcibios_plat_dev_init(struct pci_dev *dev)
+{
+	return 0;
+}
+
+static const struct of_device_id mt7620_pci_ids[] = {
+	{ .compatible = "mediatek,mt7620-pci" },
+	{},
+};
+MODULE_DEVICE_TABLE(of, mt7620_pci_ids);
+
+static struct platform_driver mt7620_pci_driver = {
+	.probe = mt7620_pci_probe,
+	.driver = {
+		.name = "mt7620-pci",
+		.owner = THIS_MODULE,
+		.of_match_table = of_match_ptr(mt7620_pci_ids),
+	},
+};
+
+static int __init mt7620_pci_init(void)
+{
+	return platform_driver_register(&mt7620_pci_driver);
+}
+
+arch_initcall(mt7620_pci_init);
--- a/arch/mips/ralink/Kconfig
+++ b/arch/mips/ralink/Kconfig
@@ -43,6 +43,7 @@ choice
 
 	config SOC_MT7620
 		bool "MT7620/8"
+		select HW_HAS_PCI
 
 	config SOC_MT7621
 		bool "MT7621"
