[PATCHv7 08/17] pci: PCIe driver for Marvell Armada 370/XP systems
Bjorn Helgaas
bhelgaas at google.com
Tue Apr 9 06:29:59 EST 2013
On Wed, Mar 27, 2013 at 8:40 AM, Thomas Petazzoni
<thomas.petazzoni at free-electrons.com> wrote:
> This driver implements the support for the PCIe interfaces on the
> Marvell Armada 370/XP ARM SoCs. In the future, it might be extended to
> cover earlier families of Marvell SoCs, such as Dove, Orion and
> Kirkwood.
>
> The driver implements the hw_pci operations needed by the core ARM PCI
> code to setup PCI devices and get their corresponding IRQs, and the
> pci_ops operations that are used by the PCI core to read/write the
> configuration space of PCI devices.
>
> Since the PCIe interfaces of Marvell SoCs are completely separate and
> not linked together in a bus, this driver sets up an emulated PCI host
> bridge, with one PCI-to-PCI bridge as child for each hardware PCIe
> interface.
>
> In addition, this driver enumerates the different PCIe slots, and for
> those having a device plugged in, it sets up the necessary address
> decoding windows, using the new armada_370_xp_alloc_pcie_window()
> function from mach-mvebu/addr-map.c.
>
> Signed-off-by: Thomas Petazzoni <thomas.petazzoni at free-electrons.com>
Acked-by: Bjorn Helgaas <bhelgaas at google.com>
A few trivial comments below; it's up to you whether you do anything
with them or not. It's OK with me if you ignore them :)
The only thing I saw that might be a bug is the resource_size()
question in mvebu_pcie_probe().
Bjorn
> diff --git a/drivers/pci/host/Makefile b/drivers/pci/host/Makefile
> new file mode 100644
> index 0000000..3ad563f
> --- /dev/null
> +++ b/drivers/pci/host/Makefile
> @@ -0,0 +1,4 @@
> +obj-$(CONFIG_PCI_MVEBU) += pci-mvebu.o
> +CFLAGS_pci-mvebu.o += \
> + -I$(srctree)/arch/arm/plat-orion/include \
> + -I$(srctree)/arch/arm/mach-mvebu/include
Too bad to have to adjust CFLAGS here. Seems like I remember earlier
discussion, but I didn't pay much attention, and if this is the best
we can do, I guess it's OK.
> diff --git a/drivers/pci/host/pci-mvebu.c b/drivers/pci/host/pci-mvebu.c
> new file mode 100644
> index 0000000..289babd
> --- /dev/null
> +++ b/drivers/pci/host/pci-mvebu.c
> @@ -0,0 +1,927 @@
> +/*
> + * 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/module.h>
> +#include <linux/mbus.h>
> +#include <linux/slab.h>
> +#include <linux/platform_device.h>
> +#include <linux/of_address.h>
> +#include <linux/of_pci.h>
> +#include <linux/of_irq.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))
Strictly speaking, I suppose you should have "(((n) - 1) ..." here.
> +#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_DATA_OFF 0x18fc
> +#define PCIE_MASK_OFF 0x1910
> +#define PCIE_CTRL_OFF 0x1a00
> +#define PCIE_CTRL_X1_MODE 0x0001
> +#define PCIE_STAT_OFF 0x1a04
> +#define PCIE_STAT_DEV_OFFS 20
> +#define PCIE_STAT_DEV_MASK 0x1f
> +#define PCIE_STAT_BUS_OFFS 8
> +#define PCIE_STAT_BUS_MASK 0xff
> +#define PCIE_STAT_LINK_DOWN 1
Whoever wrote pci_regs.h came up with a style I kind of like: the bit
masks are already shifted so you can see where they are in the value,
and there are no #defines for the shifts, e.g.,
#define PCI_EXP_FLAGS_TYPE 0x00f0 /* Device/Port type */
The users of PCI_EXP_FLAGS_TYPE just have a bare ">> 4" where
necessary. It seems like a good compromise that uses only one symbol
(good for grepping), gives good visual indication in the header file
of how the value is laid out, allows clearing bits without shifts, and
clearly shows what's happening at the uses.
But what you have is OK, too :)
> +#define PCIE_DEBUG_CTRL 0x1a60
> +#define PCIE_DEBUG_SOFT_RESET (1<<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 status;
> + 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 prefmembase;
> + u16 prefmemlimit;
> + u32 prefbaseupper;
> + u32 preflimitupper;
> + 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 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;
> + int haslink;
> + u32 port;
> + u32 lane;
> + int devfn;
> + struct clk *clk;
> + 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 int mvebu_pcie_link_up(void __iomem *base)
This could return bool, I guess.
I think I would make
mvebu_pcie_link_up()
mvebu_pcie_set_local_bus_nr()
mvebu_pcie_setup_wins()
mvebu_pcie_setup_hw()
mvebu_pcie_hw_rd_conf()
mvebu_pcie_hw_wr_conf()
all take a "struct mvebu_pcie_port *port" directly rather than having
the caller pass in "port->base", but maybe you have a reason for doing
otherwise.
> +{
> + return !(readl(base + PCIE_STAT_OFF) & PCIE_STAT_LINK_DOWN);
> +}
> +
> +static void mvebu_pcie_set_local_bus_nr(void __iomem *base, int nr)
> +{
> + u32 stat;
> +
> + stat = readl(base + PCIE_STAT_OFF);
> + stat &= ~(PCIE_STAT_BUS_MASK << PCIE_STAT_BUS_OFFS);
> + stat |= nr << PCIE_STAT_BUS_OFFS;
> + writel(stat, base + 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 void __init mvebu_pcie_setup_wins(void __iomem *base)
> +{
> + const struct mbus_dram_target_info *dram;
> + u32 size;
> + int i;
> +
> + dram = mv_mbus_dram_info();
> +
> + /*
> + * First, disable and clear BARs and windows.
> + */
Typically single-line comments would be "/* ... */" all on one line.
> + for (i = 1; i <= 2; i++) {
Interesting use of "i <= 2" rather than the typical "i < 3".
> + writel(0, base + PCIE_BAR_CTRL_OFF(i));
> + writel(0, base + PCIE_BAR_LO_OFF(i));
> + writel(0, base + PCIE_BAR_HI_OFF(i));
> + }
> +
> + for (i = 0; i < 5; i++) {
> + writel(0, base + PCIE_WIN04_CTRL_OFF(i));
> + writel(0, base + PCIE_WIN04_BASE_OFF(i));
> + writel(0, base + PCIE_WIN04_REMAP_OFF(i));
> + }
> +
> + writel(0, base + PCIE_WIN5_CTRL_OFF);
> + writel(0, base + PCIE_WIN5_BASE_OFF);
> + writel(0, base + PCIE_WIN5_REMAP_OFF);
> +
> + /*
> + * Setup windows for DDR banks. Count total DDR size on the fly.
> + */
> + size = 0;
> + for (i = 0; i < dram->num_cs; i++) {
> + const struct mbus_dram_window *cs = dram->cs + i;
> +
> + writel(cs->base & 0xffff0000, base + PCIE_WIN04_BASE_OFF(i));
> + writel(0, base + PCIE_WIN04_REMAP_OFF(i));
> + writel(((cs->size - 1) & 0xffff0000) |
> + (cs->mbus_attr << 8) |
> + (dram->mbus_dram_target_id << 4) | 1,
> + base + PCIE_WIN04_CTRL_OFF(i));
> +
> + size += cs->size;
> + }
> +
> + /*
> + * Round up 'size' to the nearest power of two.
> + */
> + if ((size & (size - 1)) != 0)
> + size = 1 << fls(size);
> +
> + /*
> + * Setup BAR[1] to all DRAM banks.
> + */
> + writel(dram->cs[0].base, base + PCIE_BAR_LO_OFF(1));
> + writel(0, base + PCIE_BAR_HI_OFF(1));
> + writel(((size - 1) & 0xffff0000) | 1, base + PCIE_BAR_CTRL_OFF(1));
> +}
> +
> +static void __init mvebu_pcie_setup_hw(void __iomem *base)
> +{
> + u16 cmd;
> + u32 mask;
> +
> + /*
> + * Point PCIe unit MBUS decode windows to DRAM space.
> + */
> + mvebu_pcie_setup_wins(base);
> +
> + /*
> + * Master + slave enable.
> + */
> + cmd = readw(base + PCIE_CMD_OFF);
> + cmd |= PCI_COMMAND_IO;
> + cmd |= PCI_COMMAND_MEMORY;
> + cmd |= PCI_COMMAND_MASTER;
> + writew(cmd, base + PCIE_CMD_OFF);
> +
> + /*
> + * Enable interrupt lines A-D.
> + */
> + mask = readl(base + PCIE_MASK_OFF);
> + mask |= 0x0f000000;
No #defines for these bits?
> + writel(mask, base + PCIE_MASK_OFF);
> +}
> +
> +static int mvebu_pcie_hw_rd_conf(void __iomem *base, struct pci_bus *bus,
> + u32 devfn, int where, int size, u32 *val)
> +{
> + writel(PCIE_CONF_BUS(bus->number) |
> + PCIE_CONF_DEV(PCI_SLOT(devfn)) |
> + PCIE_CONF_FUNC(PCI_FUNC(devfn)) |
> + PCIE_CONF_REG(where) | PCIE_CONF_ADDR_EN,
A "PCIE_CONF_ADDR(busnr, devfn, where)" macro would be nice here.
> + base + PCIE_CONF_ADDR_OFF);
> +
> + *val = readl(base + PCIE_CONF_DATA_OFF);
> +
> + if (size == 1)
> + *val = (*val >> (8 * (where & 3))) & 0xff;
> + else if (size == 2)
> + *val = (*val >> (8 * (where & 3))) & 0xffff;
> +
> + return PCIBIOS_SUCCESSFUL;
> +}
> +
> +static int mvebu_pcie_hw_wr_conf(void __iomem *base, struct pci_bus *bus,
> + u32 devfn, int where, int size, u32 val)
> +{
> + int ret = PCIBIOS_SUCCESSFUL;
> +
> + writel(PCIE_CONF_BUS(bus->number) |
> + PCIE_CONF_DEV(PCI_SLOT(devfn)) |
> + PCIE_CONF_FUNC(PCI_FUNC(devfn)) |
> + PCIE_CONF_REG(where) | PCIE_CONF_ADDR_EN,
> + base + PCIE_CONF_ADDR_OFF);
> +
> + if (size == 4)
> + writel(val, base + PCIE_CONF_DATA_OFF);
> + else if (size == 2)
> + writew(val, base + PCIE_CONF_DATA_OFF + (where & 3));
> + else if (size == 1)
> + writeb(val, base + PCIE_CONF_DATA_OFF + (where & 3));
> + else
> + ret = PCIBIOS_BAD_REGISTER_NUMBER;
> +
> + return ret;
> +}
> +
> +static void mvebu_pcie_handle_iobase_change(struct mvebu_pcie_port *port)
> +{
> + phys_addr_t iobase;
> +
> + /* Are the current iobase/iolimit values invalid? */
I first thought "current ... values" meant "the values before the
change." If you used "new values" it might be clearer that this is
used to handle *writes* to the window base/size registers, and that
we're looking at the values being written.
> + if (port->bridge.iolimit < port->bridge.iobase ||
> + port->bridge.iolimitupper < port->bridge.iobaseupper) {
> +
> + /* If a window was configured, remove it */
> + if (port->iowin_base) {
> + mvebu_mbus_del_window(port->iowin_base,
> + port->iowin_size);
> + port->iowin_base = 0;
> + port->iowin_size = 0;
> + }
> +
> + return;
> + }
> +
> + /*
> + * We read the PCI-to-PCI bridge emulated registers, and
> + * calculate the base address and size of the address decoding
> + * window to setup, according to the PCI-to-PCI bridge
> + * specifications. iobase is the bus address, port->iowin_base
> + * is the CPU address.
> + */
> + iobase = ((port->bridge.iobase & 0xF0) << 8) |
> + (port->bridge.iobaseupper << 16);
> + port->iowin_base = port->pcie->io.start + iobase;
> + port->iowin_size = ((0xFFF | ((port->bridge.iolimit & 0xF0) << 8) |
> + (port->bridge.iolimitupper << 16)) -
> + iobase);
> +
> + mvebu_mbus_add_window_remap_flags(port->name, port->iowin_base,
> + port->iowin_size,
> + iobase,
> + MVEBU_MBUS_PCI_IO);
> +
> + pci_ioremap_io(iobase, port->iowin_base);
> +}
> +
> +static void mvebu_pcie_handle_membase_change(struct mvebu_pcie_port *port)
> +{
> + /* Are the current membase/memlimit values invalid? */
> + if (port->bridge.memlimit < port->bridge.membase) {
> +
> + /* If a window was configured, remove it */
> + if (port->memwin_base) {
> + mvebu_mbus_del_window(port->memwin_base,
> + port->memwin_size);
> + port->memwin_base = 0;
> + port->memwin_size = 0;
> + }
> +
> + return;
> + }
> +
> + /*
> + * We read the PCI-to-PCI bridge emulated registers, and
> + * calculate the base address and size of the address decoding
> + * window to setup, according to the PCI-to-PCI bridge
> + * specifications.
> + */
> + port->memwin_base = ((port->bridge.membase & 0xFFF0) << 16);
> + port->memwin_size =
> + (((port->bridge.memlimit & 0xFFF0) << 16) | 0xFFFFF) -
> + port->memwin_base;
> +
> + mvebu_mbus_add_window_remap_flags(port->name, port->memwin_base,
> + port->memwin_size,
> + MVEBU_MBUS_NO_REMAP,
> + MVEBU_MBUS_PCI_MEM);
> +}
> +
> +/*
> + * Initialize the configuration space of the PCI-to-PCI bridge
> + * associated with the given PCIe interface.
> + */
> +static void mvebu_sw_pci_bridge_init(struct mvebu_pcie_port *port)
> +{
> + struct mvebu_sw_pci_bridge *bridge = &port->bridge;
> +
> + memset(bridge, 0, sizeof(struct mvebu_sw_pci_bridge));
> +
> + bridge->status = PCI_STATUS_CAP_LIST;
> + bridge->class = PCI_CLASS_BRIDGE_PCI;
> + bridge->vendor = PCI_VENDOR_ID_MARVELL;
> + bridge->device = MARVELL_EMULATED_PCI_PCI_BRIDGE_ID;
> + bridge->header_type = PCI_HEADER_TYPE_BRIDGE;
> + bridge->cache_line_size = 0x10;
> +
> + /* We support 32 bits I/O addressing */
> + bridge->iobase = PCI_IO_RANGE_TYPE_32;
> + bridge->iolimit = PCI_IO_RANGE_TYPE_32;
> +}
> +
> +/*
> + * Read the configuration space of the PCI-to-PCI bridge associated to
> + * the given PCIe interface.
> + */
> +static int mvebu_sw_pci_bridge_read(struct mvebu_pcie_port *port,
> + unsigned int where, int size, u32 *value)
> +{
> + struct mvebu_sw_pci_bridge *bridge = &port->bridge;
> +
> + switch (where & ~3) {
> + case PCI_VENDOR_ID:
> + *value = bridge->device << 16 | bridge->vendor;
> + break;
> +
> + case PCI_COMMAND:
> + *value = bridge->status << 16 | bridge->command;
> + break;
> +
> + case PCI_CLASS_REVISION:
> + *value = bridge->class << 16 | bridge->interface << 8 |
> + bridge->revision;
> + break;
> +
> + case PCI_CACHE_LINE_SIZE:
> + *value = bridge->bist << 24 | bridge->header_type << 16 |
> + bridge->latency_timer << 8 | bridge->cache_line_size;
> + break;
> +
> + case PCI_BASE_ADDRESS_0 ... PCI_BASE_ADDRESS_1:
> + *value = bridge->bar[((where & ~3) - PCI_BASE_ADDRESS_0) / 4];
> + break;
> +
> + case PCI_PRIMARY_BUS:
> + *value = (bridge->secondary_latency_timer << 24 |
> + bridge->subordinate_bus << 16 |
> + bridge->secondary_bus << 8 |
> + bridge->primary_bus);
> + break;
> +
> + case PCI_IO_BASE:
> + *value = (bridge->secondary_status << 16 |
> + bridge->iolimit << 8 |
> + bridge->iobase);
> + break;
> +
> + case PCI_MEMORY_BASE:
> + *value = (bridge->memlimit << 16 | bridge->membase);
> + break;
> +
> + case PCI_PREF_MEMORY_BASE:
> + *value = (bridge->prefmemlimit << 16 | bridge->prefmembase);
> + break;
> +
> + case PCI_PREF_BASE_UPPER32:
> + *value = bridge->prefbaseupper;
> + break;
> +
> + case PCI_PREF_LIMIT_UPPER32:
> + *value = bridge->preflimitupper;
> + break;
> +
> + case PCI_IO_BASE_UPPER16:
> + *value = (bridge->iolimitupper << 16 | bridge->iobaseupper);
> + break;
> +
> + case PCI_ROM_ADDRESS1:
> + *value = 0;
> + break;
> +
> + default:
> + *value = 0xffffffff;
> + return PCIBIOS_BAD_REGISTER_NUMBER;
> + }
> +
> + if (size == 2)
> + *value = (*value >> (8 * (where & 3))) & 0xffff;
> + else if (size == 1)
> + *value = (*value >> (8 * (where & 3))) & 0xff;
> +
> + return PCIBIOS_SUCCESSFUL;
> +}
> +
> +/* Write to the PCI-to-PCI bridge configuration space */
> +static int mvebu_sw_pci_bridge_write(struct mvebu_pcie_port *port,
> + unsigned int where, int size, u32 value)
> +{
> + struct mvebu_sw_pci_bridge *bridge = &port->bridge;
> + u32 mask, reg;
> + int err;
> +
> + if (size == 4)
> + mask = 0x0;
> + else if (size == 2)
> + mask = ~(0xffff << ((where & 3) * 8));
> + else if (size == 1)
> + mask = ~(0xff << ((where & 3) * 8));
> + else
> + return PCIBIOS_BAD_REGISTER_NUMBER;
> +
> + err = mvebu_sw_pci_bridge_read(port, where & ~3, 4, ®);
> + if (err)
> + return err;
> +
> + value = (reg & mask) | value << ((where & 3) * 8);
> +
> + switch (where & ~3) {
> + case PCI_COMMAND:
> + bridge->command = value & 0xffff;
> + bridge->status = value >> 16;
> + break;
> +
> + case PCI_BASE_ADDRESS_0 ... PCI_BASE_ADDRESS_1:
> + bridge->bar[((where & ~3) - PCI_BASE_ADDRESS_0) / 4] = value;
> + break;
> +
> + case PCI_IO_BASE:
> + /*
> + * We also keep bit 1 set, it is a read-only bit that
> + * indicates we support 32 bits addressing for the
> + * I/O
> + */
> + bridge->iobase = (value & 0xff) | PCI_IO_RANGE_TYPE_32;
> + bridge->iolimit = ((value >> 8) & 0xff) | PCI_IO_RANGE_TYPE_32;
> + bridge->secondary_status = value >> 16;
> + mvebu_pcie_handle_iobase_change(port);
> + break;
> +
> + case PCI_MEMORY_BASE:
> + bridge->membase = value & 0xffff;
> + bridge->memlimit = value >> 16;
> + mvebu_pcie_handle_membase_change(port);
> + break;
> +
> + case PCI_PREF_MEMORY_BASE:
> + bridge->prefmembase = value & 0xffff;
> + bridge->prefmemlimit = value >> 16;
> + break;
> +
> + case PCI_PREF_BASE_UPPER32:
> + bridge->prefbaseupper = value;
> + break;
> +
> + case PCI_PREF_LIMIT_UPPER32:
> + bridge->preflimitupper = value;
> + break;
> +
> + case PCI_IO_BASE_UPPER16:
> + bridge->iobaseupper = value & 0xffff;
> + bridge->iolimitupper = value >> 16;
> + mvebu_pcie_handle_iobase_change(port);
> + break;
> +
> + case PCI_PRIMARY_BUS:
> + bridge->primary_bus = value & 0xff;
> + bridge->secondary_bus = (value >> 8) & 0xff;
> + bridge->subordinate_bus = (value >> 16) & 0xff;
> + bridge->secondary_latency_timer = (value >> 24) & 0xff;
> + mvebu_pcie_set_local_bus_nr(port->base, bridge->secondary_bus);
> + break;
> +
> + default:
> + break;
> + }
> +
> + return PCIBIOS_SUCCESSFUL;
> +}
> +
> +static inline struct mvebu_pcie *sys_to_pcie(struct pci_sys_data *sys)
> +{
> + return sys->private_data;
> +}
> +
> +/* Find the PCIe interface that corresponds to the given bus */
> +static struct mvebu_pcie_port *mvebu_find_port_from_bus(struct mvebu_pcie *pcie,
> + int bus)
> +{
> + int porti;
> +
> + for (porti = 0; porti < pcie->nports; porti++)
> + if (pcie->ports[porti].bridge.secondary_bus == bus)
> + return &pcie->ports[porti];
> +
> + return NULL;
> +}
> +
> +/* Find the PCIe interface that corresponds to the given devfn */
> +static struct mvebu_pcie_port *
> +mvebu_find_port_from_devfn(struct mvebu_pcie *pcie, int devfn)
> +{
> + int porti;
> +
> + for (porti = 0; porti < pcie->nports; porti++)
> + if (pcie->ports[porti].devfn == devfn)
> + return &pcie->ports[porti];
> +
> + return NULL;
> +}
> +
> +/* PCI configuration space write function */
> +static int mvebu_pcie_wr_conf(struct pci_bus *bus, u32 devfn,
> + int where, int size, u32 val)
> +{
> + struct mvebu_pcie *pcie = sys_to_pcie(bus->sysdata);
> +
> + if (bus->number != 0) {
> + /*
> + * Accessing a real PCIe interface.
> + */
> + struct mvebu_pcie_port *port;
> + unsigned long flags;
> + int ret;
> +
> + port = mvebu_find_port_from_bus(pcie, bus->number);
> + if (!port)
> + return PCIBIOS_DEVICE_NOT_FOUND;
> +
> + if (!port->haslink)
> + return PCIBIOS_DEVICE_NOT_FOUND;
> +
> + if (PCI_SLOT(devfn) != 0)
> + return PCIBIOS_DEVICE_NOT_FOUND;
> +
> + spin_lock_irqsave(&port->conf_lock, flags);
> + ret = mvebu_pcie_hw_wr_conf(port->base, bus,
> + PCI_DEVFN(1, PCI_FUNC(devfn)),
> + where, size, val);
> + spin_unlock_irqrestore(&port->conf_lock, flags);
> +
> + return ret;
> + } else {
> + /*
> + * Access the emulated PCI-to-PCI bridges.
> + */
> + struct mvebu_pcie_port *port;
> + port = mvebu_find_port_from_devfn(pcie, devfn);
> + if (!port)
> + return PCIBIOS_DEVICE_NOT_FOUND;
> +
> + return mvebu_sw_pci_bridge_write(port, where, size, val);
> + }
> +
> + return PCIBIOS_SUCCESSFUL;
This last "return" is unreachable (I see you omitted it from the
rd_conf() path already :)). This would be slightly simpler as:
static struct mvebu_pcie_port *mvebu_find_port(struct mvebu_pcie *pcie,
struct pci_bus *bus, int devfn)
{
int i;
for (i = 0; i < pcie->nports; i++) {
if ((bus->number == 0 && pcie->ports[i].devfn == devfn) ||
(pcie->ports[porti].bridge.secondary_bus == bus->number))
return &pcie->ports[i];
}
return NULL;
}
static int mvebu_pcie_wr_conf(struct pci_bus *bus, ...)
{
port = mvebu_find_port(pcie, bus, devfn);
if (!port)
return PCIBIOS_DEVICE_NOT_FOUND;
if (bus->number == 0)
return mvebu_sw_pci_bridge_write(port, where, size, val);
if (!port->haslink || PCI_SLOT(devfn) != 0)
return PCIBIOS_DEVICE_NOT_FOUND;
...
return ret;
}
> +}
> +
> +/* PCI configuration space read function */
> +static int mvebu_pcie_rd_conf(struct pci_bus *bus, u32 devfn, int where,
> + int size, u32 *val)
> +{
> + struct mvebu_pcie *pcie = sys_to_pcie(bus->sysdata);
> +
> + if (bus->number != 0) {
> + /*
> + * Accessing a real PCIe interface.
> + */
> + struct mvebu_pcie_port *port;
> + unsigned long flags;
> + int ret;
> +
> + port = mvebu_find_port_from_bus(pcie, bus->number);
> + if (!port) {
> + *val = 0xffffffff;
> + return PCIBIOS_DEVICE_NOT_FOUND;
> + }
> +
> + if (!port->haslink || PCI_SLOT(devfn) != 0) {
> + *val = 0xffffffff;
> + return PCIBIOS_DEVICE_NOT_FOUND;
> + }
> +
> + spin_lock_irqsave(&port->conf_lock, flags);
> + ret = mvebu_pcie_hw_rd_conf(port->base, bus,
> + PCI_DEVFN(1, PCI_FUNC(devfn)),
> + where, size, val);
> + spin_unlock_irqrestore(&port->conf_lock, flags);
> +
> + return ret;
> + } else {
> + /*
> + * Access the emulated PCI-to-PCI bridges.
> + */
> + struct mvebu_pcie_port *port;
> + port = mvebu_find_port_from_devfn(pcie, devfn);
> + if (!port) {
> + *val = 0xffffffff;
> + return PCIBIOS_DEVICE_NOT_FOUND;
> + }
> +
> + return mvebu_sw_pci_bridge_read(port, where, size, val);
> + }
> +}
> +
> +static struct pci_ops mvebu_pcie_ops = {
> + .read = mvebu_pcie_rd_conf,
> + .write = mvebu_pcie_wr_conf,
> +};
> +
> +static int __init mvebu_pcie_setup(int nr, struct pci_sys_data *sys)
> +{
> + struct mvebu_pcie *pcie = sys_to_pcie(sys);
> + int i;
> +
> + pci_add_resource_offset(&sys->resources, &pcie->realio, sys->io_offset);
> + pci_add_resource_offset(&sys->resources, &pcie->mem, sys->mem_offset);
> + pci_add_resource(&sys->resources, &pcie->busn);
> +
> + for (i = 0; i < pcie->nports; i++) {
> + struct mvebu_pcie_port *port = &pcie->ports[i];
> + mvebu_pcie_setup_hw(port->base);
> + }
> +
> + return 1;
> +}
> +
> +static int __init mvebu_pcie_map_irq(const struct pci_dev *dev, u8 slot, u8 pin)
> +{
> + struct of_irq oirq;
> + int ret;
> +
> + ret = of_irq_map_pci(dev, &oirq);
> + if (ret)
> + return ret;
> +
> + return irq_create_of_mapping(oirq.controller, oirq.specifier,
> + oirq.size);
> +}
> +
> +static struct pci_bus *mvebu_pcie_scan_bus(int nr, struct pci_sys_data *sys)
> +{
> + struct mvebu_pcie *pcie = sys_to_pcie(sys);
> + struct pci_bus *bus;
> +
> + bus = pci_create_root_bus(&pcie->pdev->dev, sys->busnr,
> + &mvebu_pcie_ops, sys, &sys->resources);
> + if (!bus)
> + return NULL;
> +
> + pci_scan_child_bus(bus);
> +
> + return bus;
> +}
> +
> +resource_size_t mvebu_pcie_align_resource(struct pci_dev *dev,
> + const struct resource *res,
> + resource_size_t start,
> + resource_size_t size,
> + resource_size_t align)
> +{
> + if (dev->bus->number != 0)
> + return start;
> +
> + /*
> + * On the PCI-to-PCI bridge side, the I/O windows must have at
> + * least a 64 KB size and be aligned on their size, and the
> + * memory windows must have at least a 1 MB size and be
> + * aligned on their size
> + */
> + if (res->flags & IORESOURCE_IO)
> + return round_up(start, max((resource_size_t)SZ_64K, size));
> + else if (res->flags & IORESOURCE_MEM)
> + return round_up(start, max((resource_size_t)SZ_1M, size));
> + else
> + return start;
> +}
> +
> +static void mvebu_pcie_enable(struct mvebu_pcie *pcie)
> +{
> + struct hw_pci hw;
> +
> + memset(&hw, 0, sizeof(hw));
> +
> + hw.nr_controllers = 1;
> + hw.private_data = (void **)&pcie;
> + hw.setup = mvebu_pcie_setup;
> + hw.scan = mvebu_pcie_scan_bus;
> + hw.map_irq = mvebu_pcie_map_irq;
> + hw.ops = &mvebu_pcie_ops;
> + hw.align_resource = mvebu_pcie_align_resource;
> +
> + pci_common_init(&hw);
> +}
> +
> +/*
> + * Looks up the list of register addresses encoded into the reg =
> + * <...> property for one that matches the given port/lane. Once
> + * found, maps it.
> + */
> +static void __iomem *mvebu_pcie_map_registers(struct platform_device *pdev,
> + struct device_node *np,
> + struct mvebu_pcie_port *port)
> +{
> + struct resource regs;
> + int ret = 0;
> +
> + ret = of_address_to_resource(np, 0, ®s);
> + if (ret)
> + return NULL;
> +
> + return devm_request_and_ioremap(&pdev->dev, ®s);
> +}
> +
> +static int __init mvebu_pcie_probe(struct platform_device *pdev)
> +{
> + struct mvebu_pcie *pcie;
> + struct device_node *np = pdev->dev.of_node;
> + struct of_pci_range range;
> + struct of_pci_range_parser parser;
> + struct device_node *child;
> + int i, ret;
> +
> + pcie = devm_kzalloc(&pdev->dev, sizeof(struct mvebu_pcie),
> + GFP_KERNEL);
> + if (!pcie)
> + return -ENOMEM;
> +
> + pcie->pdev = pdev;
> +
> + if (of_pci_range_parser(&parser, np))
> + return -EINVAL;
> +
> + /* Get the I/O and memory ranges from DT */
> + for_each_of_pci_range(&parser, &range) {
> + unsigned long restype = range.flags & IORESOURCE_TYPE_BITS;
> + if (restype == IORESOURCE_IO) {
> + of_pci_range_to_resource(&range, np, &pcie->io);
> + of_pci_range_to_resource(&range, np, &pcie->realio);
> + pcie->io.name = "I/O";
> + pcie->realio.start = PCIBIOS_MIN_IO;
> + pcie->realio.end = min(resource_size(&pcie->io),
> + IO_SPACE_LIMIT);
Using "resource_size(&pcie->io)" here seems strange -- are you
assuming that pcie->io starts at address zero?
> + }
> + if (restype == IORESOURCE_MEM) {
> + of_pci_range_to_resource(&range, np, &pcie->mem);
> + pcie->mem.name = "MEM";
> + }
> + }
> +
> + /* Get the bus range */
> + ret = of_pci_parse_bus_range(np, &pcie->busn);
> + if (ret) {
> + dev_err(&pdev->dev, "failed to parse bus-range property: %d\n",
> + ret);
> + return ret;
> + }
> +
> + for_each_child_of_node(pdev->dev.of_node, child) {
> + if (!of_device_is_available(child))
> + continue;
> + pcie->nports++;
> + }
> +
> + pcie->ports = devm_kzalloc(&pdev->dev, pcie->nports *
> + sizeof(struct mvebu_pcie_port),
> + GFP_KERNEL);
> + if (!pcie->ports)
> + return -ENOMEM;
> +
> + i = 0;
> + for_each_child_of_node(pdev->dev.of_node, child) {
> + struct mvebu_pcie_port *port = &pcie->ports[i];
> +
> + if (!of_device_is_available(child))
> + continue;
> +
> + port->pcie = pcie;
> +
> + if (of_property_read_u32(child, "marvell,pcie-port",
> + &port->port)) {
> + dev_warn(&pdev->dev,
> + "ignoring PCIe DT node, missing pcie-port property\n");
> + continue;
> + }
> +
> + if (of_property_read_u32(child, "marvell,pcie-lane",
> + &port->lane))
> + port->lane = 0;
> +
> + port->name = kasprintf(GFP_KERNEL, "pcie%d.%d",
> + port->port, port->lane);
> +
> + port->devfn = of_pci_get_devfn(child);
> + if (port->devfn < 0)
> + continue;
> +
> + port->base = mvebu_pcie_map_registers(pdev, child, port);
> + if (!port->base) {
> + dev_err(&pdev->dev, "PCIe%d.%d: cannot map registers\n",
> + port->port, port->lane);
> + continue;
> + }
> +
> + if (mvebu_pcie_link_up(port->base)) {
> + port->haslink = 1;
> + dev_info(&pdev->dev, "PCIe%d.%d: link up\n",
> + port->port, port->lane);
> + } else {
> + port->haslink = 0;
> + dev_info(&pdev->dev, "PCIe%d.%d: link down\n",
> + port->port, port->lane);
> + }
> +
> + port->clk = of_clk_get_by_name(child, NULL);
> + if (!port->clk) {
> + dev_err(&pdev->dev, "PCIe%d.%d: cannot get clock\n",
> + port->port, port->lane);
> + iounmap(port->base);
> + port->haslink = 0;
> + continue;
> + }
> +
> + port->dn = child;
> +
> + clk_prepare_enable(port->clk);
> + spin_lock_init(&port->conf_lock);
> +
> + mvebu_sw_pci_bridge_init(port);
> +
> + i++;
> + }
> +
> + mvebu_pcie_enable(pcie);
> +
> + return 0;
> +}
> +
> +static const struct of_device_id mvebu_pcie_of_match_table[] = {
> + { .compatible = "marvell,armada-xp-pcie", },
> + { .compatible = "marvell,armada-370-pcie", },
> + {},
> +};
> +MODULE_DEVICE_TABLE(of, mvebu_pcie_of_match_table);
> +
> +static struct platform_driver mvebu_pcie_driver = {
> + .driver = {
> + .owner = THIS_MODULE,
> + .name = "mvebu-pcie",
> + .of_match_table =
> + of_match_ptr(mvebu_pcie_of_match_table),
> + },
> +};
> +
> +static int mvebu_pcie_init(void)
> +{
> + return platform_driver_probe(&mvebu_pcie_driver,
> + mvebu_pcie_probe);
> +}
> +
> +subsys_initcall(mvebu_pcie_init);
> +
> +MODULE_AUTHOR("Thomas Petazzoni <thomas.petazzoni at free-electrons.com>");
> +MODULE_DESCRIPTION("Marvell EBU PCIe driver");
> +MODULE_LICENSE("GPLv2");
> --
> 1.7.9.5
>
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