path: root/drivers/pci/host/pci-mvebu.c

/*
 * PCIe driver for Marvell Armada 370 and Armada XP SoCs
 *
 * This file is licensed under the terms of the GNU General Public
 * License version 2.  This program is licensed "as is" without any
 * warranty of any kind, whether express or implied.
 */

#include <linux/kernel.h>
#include <linux/pci.h>
#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/gpio.h>
#include <linux/module.h>
#include <linux/mbus.h>
#include <linux/msi.h>
#include <linux/slab.h>
#include <linux/platform_device.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
#include <linux/of_gpio.h>
#include <linux/of_pci.h>
#include <linux/of_platform.h>

/*
 * PCIe unit register offsets.
 */
#define PCIE_DEV_ID_OFF		0x0000
#define PCIE_CMD_OFF		0x0004
#define PCIE_DEV_REV_OFF	0x0008
#define PCIE_BAR_LO_OFF(n)	(0x0010 + ((n) << 3))
#define PCIE_BAR_HI_OFF(n)	(0x0014 + ((n) << 3))
#define PCIE_HEADER_LOG_4_OFF	0x0128
#define PCIE_BAR_CTRL_OFF(n)	(0x1804 + (((n) - 1) * 4))
#define PCIE_WIN04_CTRL_OFF(n)	(0x1820 + ((n) << 4))
#define PCIE_WIN04_BASE_OFF(n)	(0x1824 + ((n) << 4))
#define PCIE_WIN04_REMAP_OFF(n)	(0x182c + ((n) << 4))
#define PCIE_WIN5_CTRL_OFF	0x1880
#define PCIE_WIN5_BASE_OFF	0x1884
#define PCIE_WIN5_REMAP_OFF	0x188c
#define PCIE_CONF_ADDR_OFF	0x18f8
#define  PCIE_CONF_ADDR_EN		0x80000000
#define  PCIE_CONF_REG(r)		((((r) & 0xf00) << 16) | ((r) & 0xfc))
#define  PCIE_CONF_BUS(b)		(((b) & 0xff) << 16)
#define  PCIE_CONF_DEV(d)		(((d) & 0x1f) << 11)
#define  PCIE_CONF_FUNC(f)		(((f) & 0x7) << 8)
#define  PCIE_CONF_ADDR(bus, devfn, where) \
	(PCIE_CONF_BUS(bus) | PCIE_CONF_DEV(PCI_SLOT(devfn))    | \
	 PCIE_CONF_FUNC(PCI_FUNC(devfn)) | PCIE_CONF_REG(where) | \
	 PCIE_CONF_ADDR_EN)
#define PCIE_CONF_DATA_OFF	0x18fc
#define PCIE_MASK_OFF		0x1910
#define  PCIE_MASK_ENABLE_INTS          0x0f000000
#define PCIE_CTRL_OFF		0x1a00
#define  PCIE_CTRL_X1_MODE		0x0001
#define PCIE_STAT_OFF		0x1a04
#define  PCIE_STAT_BUS                  0xff00
#define  PCIE_STAT_DEV                  0x1f0000
#define  PCIE_STAT_LINK_DOWN		BIT(0)
#define PCIE_DEBUG_CTRL         0x1a60
#define  PCIE_DEBUG_SOFT_RESET		BIT(20)

/*
 * This product ID is registered by Marvell, and used when the Marvell
 * SoC is not the root complex, but an endpoint on the PCIe bus. It is
 * therefore safe to re-use this PCI ID for our emulated PCI-to-PCI
 * bridge.
 */
#define MARVELL_EMULATED_PCI_PCI_BRIDGE_ID 0x7846

/* PCI configuration space of a PCI-to-PCI bridge */
struct mvebu_sw_pci_bridge {
	u16 vendor;
	u16 device;
	u16 command;
	u16 class;
	u8 interface;
	u8 revision;
	u8 bist;
	u8 header_type;
	u8 latency_timer;
	u8 cache_line_size;
	u32 bar[2];
	u8 primary_bus;
	u8 secondary_bus;
	u8 subordinate_bus;
	u8 secondary_latency_timer;
	u8 iobase;
	u8 iolimit;
	u16 secondary_status;
	u16 membase;
	u16 memlimit;
	u16 iobaseupper;
	u16 iolimitupper;
	u8 cappointer;
	u8 reserved1;
	u16 reserved2;
	u32 romaddr;
	u8 intline;
	u8 intpin;
	u16 bridgectrl;
};

struct mvebu_pcie_port;

/* Structure representing all PCIe interfaces */
struct mvebu_pcie {
	struct platform_device *pdev;
	struct mvebu_pcie_port *ports;
	struct msi_chip *msi;
	struct resource io;
	struct resource realio;
	struct resource mem;
	struct resource busn;
	int nports;
};

/* Structure representing one PCIe interface */
struct mvebu_pcie_port {
	char *name;
	void __iomem *base;
	spinlock_t conf_lock;
	u32 port;
	u32 lane;
	int devfn;
	unsigned int mem_target;
	unsigned int mem_attr;
	unsigned int io_target;
	unsigned int io_attr;
	struct clk *clk;
	int reset_gpio;
	int reset_active_low;
	char *reset_name;
	struct mvebu_sw_pci_bridge bridge;
	struct device_node *dn;
	struct mvebu_pcie *pcie;
	phys_addr_t memwin_base;
	size_t memwin_size;
	phys_addr_t iowin_base;
	size_t iowin_size;
};

static inline void mvebu_writel(struct mvebu_pcie_port *port, u32 val, u32 reg)
{
	writel(val, port->base + reg);
}

static inline u32 mvebu_readl(struct mvebu_pcie_port *port, u32 reg)
{
	return readl(port->base + reg);
}

static inline bool mvebu_has_ioport(struct mvebu_pcie_port *port)
{
	return port->io_target != -1 && port->io_attr != -1;
}

static bool mvebu_pcie_link_up(struct mvebu_pcie_port *port)
{
	return !(mvebu_readl(port, PCIE_STAT_OFF) & PCIE_STAT_LINK_DOWN);
}

static void mvebu_pcie_set_local_bus_nr(struct mvebu_pcie_port *port, int nr)
{
	u32 stat;

	stat = mvebu_readl(port, PCIE_STAT_OFF);
	stat &= ~PCIE_STAT_BUS;
	stat |= nr << 8;
	mvebu_writel(port, stat, PCIE_STAT_OFF);
}

static void mvebu_pcie_set_local_dev_nr(struct mvebu_pcie_port *port, int nr)
{
	u32 stat;

	stat = mvebu_readl(port, PCIE_STAT_OFF);
	stat &= ~PCIE_STAT_DEV;
	stat |= nr << 16;
	mvebu_writel(port, stat, PCIE_STAT_OFF);
}

/*
 * Setup PCIE BARs and Address Decode Wins:
 * BAR[0,2] -> disabled, BAR[1] -> covers all DRAM banks
 * WIN[0-3] -> DRAM bank[0-3]
 */
static