MIPS: Netlogic: XLP PCIe controller support.

Adds support for the XLP on-chip PCIe controller. On XLP, the
on-chip devices(including the 4 PCIe links) appear in the PCIe
configuration space of the XLP as PCI devices.

The changes are to initialize and register the PCIe controller,
enable hardware byte swap in the PCIe IO and MEM space, and to
enable PCIe interrupts.

Signed-off-by: Ganesan Ramalingam <ganesanr@netlogicmicro.com>
Signed-off-by: Jayachandran C <jayachandranc@netlogicmicro.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/3760/
Patchwork: https://patchwork.linux-mips.org/patch/4104/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

1 files changed, 248 insertions, 0 deletions

diff --git a/arch/mips/pci/pci-xlp.c b/arch/mips/pci/pci-xlp.c
new file mode 100644
index 000000000000..140557a20488
--- /dev/null
+++ b/arch/mips/pci/pci-xlp.c
@@ -0,0 +1,248 @@
+/*
+ * Copyright (c) 2003-2012 Broadcom Corporation
+ * All Rights Reserved
+ *
+ * This software is available to you under a choice of one of two
+ * licenses.  You may choose to be licensed under the terms of the GNU
+ * General Public License (GPL) Version 2, available from the file
+ * COPYING in the main directory of this source tree, or the Broadcom
+ * license below:
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY BROADCOM ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL BROADCOM OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
+ * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+ * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
+ * OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN
+ * IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <linux/types.h>
+#include <linux/pci.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/msi.h>
+#include <linux/mm.h>
+#include <linux/irq.h>
+#include <linux/irqdesc.h>
+#include <linux/console.h>
+
+#include <asm/io.h>
+
+#include <asm/netlogic/interrupt.h>
+#include <asm/netlogic/haldefs.h>
+
+#include <asm/netlogic/xlp-hal/iomap.h>
+#include <asm/netlogic/xlp-hal/pic.h>
+#include <asm/netlogic/xlp-hal/xlp.h>
+#include <asm/netlogic/xlp-hal/pcibus.h>
+#include <asm/netlogic/xlp-hal/bridge.h>
+
+static void *pci_config_base;
+
+#define pci_cfg_addr(bus, devfn, off) (((bus) << 20) | ((devfn) << 12) | (off))
+
+/* PCI ops */
+static inline u32 pci_cfg_read_32bit(struct pci_bus *bus, unsigned int devfn,
+        int where)
+{
+        u32 data;
+        u32 *cfgaddr;
+
+        cfgaddr = (u32 *)(pci_config_base +
+                        pci_cfg_addr(bus->number, devfn, where & ~3));
+        data = *cfgaddr;
+        return data;
+}
+
+static inline void pci_cfg_write_32bit(struct pci_bus *bus, unsigned int devfn,
+        int where, u32 data)
+{
+        u32 *cfgaddr;
+
+        cfgaddr = (u32 *)(pci_config_base +
+                        pci_cfg_addr(bus->number, devfn, where & ~3));
+        *cfgaddr = data;
+}
+
+static int nlm_pcibios_read(struct pci_bus *bus, unsigned int devfn,
+        int where, int size, u32 *val)
+{
+        u32 data;
+
+        if ((size == 2) && (where & 1))
+                return PCIBIOS_BAD_REGISTER_NUMBER;
+        else if ((size == 4) && (where & 3))
+                return PCIBIOS_BAD_REGISTER_NUMBER;
+
+        data = pci_cfg_read_32bit(bus, devfn, where);
+
+        if (size == 1)
+                *val = (data >> ((where & 3) << 3)) & 0xff;
+        else if (size == 2)
+                *val = (data >> ((where & 3) << 3)) & 0xffff;
+        else
+                *val = data;
+
+        return PCIBIOS_SUCCESSFUL;
+}
+
+
+static int nlm_pcibios_write(struct pci_bus *bus, unsigned int devfn,
+                int where, int size, u32 val)
+{
+        u32 data;
+
+        if ((size == 2) && (where & 1))
+                return PCIBIOS_BAD_REGISTER_NUMBER;
+        else if ((size == 4) && (where & 3))
+                return PCIBIOS_BAD_REGISTER_NUMBER;
+
+        data = pci_cfg_read_32bit(bus, devfn, where);
+
+        if (size == 1)
+                data = (data & ~(0xff << ((where & 3) << 3))) |
+                        (val << ((where & 3) << 3));
+        else if (size == 2)
+                data = (data & ~(0xffff << ((where & 3) << 3))) |
+                        (val << ((where & 3) << 3));
+        else
+                data = val;
+
+        pci_cfg_write_32bit(bus, devfn, where, data);
+
+        return PCIBIOS_SUCCESSFUL;
+}
+
+struct pci_ops nlm_pci_ops = {
+        .read  = nlm_pcibios_read,
+        .write = nlm_pcibios_write
+};
+
+static struct resource nlm_pci_mem_resource = {
+        .name           = "XLP PCI MEM",
+        .start          = 0xd0000000UL, /* 256MB PCI mem @ 0xd000_0000 */
+        .end            = 0xdfffffffUL,
+        .flags          = IORESOURCE_MEM,
+};
+
+static struct resource nlm_pci_io_resource = {
+        .name           = "XLP IO MEM",
+        .start          = 0x14000000UL, /* 64MB PCI IO @ 0x1000_0000 */
+        .end            = 0x17ffffffUL,
+        .flags          = IORESOURCE_IO,
+};
+
+struct pci_controller nlm_pci_controller = {
+        .index          = 0,
+        .pci_ops        = &nlm_pci_ops,
+        .mem_resource   = &nlm_pci_mem_resource,
+        .mem_offset     = 0x00000000UL,
+        .io_resource    = &nlm_pci_io_resource,
+        .io_offset      = 0x00000000UL,
+};
+
+static int get_irq_vector(const struct pci_dev *dev)
+{
+        /*
+         * For XLP PCIe, there is an IRQ per Link, find out which
+         * link the device is on to assign interrupts
+        */
+        if (dev->bus->self == NULL)
+                return 0;
+
+        switch  (dev->bus->self->devfn) {
+        case 0x8:
+                return PIC_PCIE_LINK_0_IRQ;
+        case 0x9:
+                return PIC_PCIE_LINK_1_IRQ;
+        case 0xa:
+                return PIC_PCIE_LINK_2_IRQ;
+        case 0xb:
+                return PIC_PCIE_LINK_3_IRQ;
+        }
+        WARN(1, "Unexpected devfn %d\n", dev->bus->self->devfn);
+        return 0;
+}
+
+int __init pcibios_map_irq(const struct pci_dev *dev, u8 slot, u8 pin)
+{
+        return get_irq_vector(dev);
+}
+
+/* Do platform specific device initialization at pci_enable_device() time */
+int pcibios_plat_dev_init(struct pci_dev *dev)
+{
+        return 0;
+}
+
+static int xlp_enable_pci_bswap(void)
+{
+        uint64_t pciebase, sysbase;
+        int node, i;
+        u32 reg;
+
+        /* Chip-0 so node set to 0 */
+        node = 0;
+        sysbase = nlm_get_bridge_regbase(node);
+        /*
+         *  Enable byte swap in hardware. Program each link's PCIe SWAP regions
+         * from the link's address ranges.
+         */
+        for (i = 0; i < 4; i++) {
+                pciebase = nlm_pcicfg_base(XLP_IO_PCIE_OFFSET(node, i));
+                if (nlm_read_pci_reg(pciebase, 0) == 0xffffffff)
+                        continue;
+
+                reg = nlm_read_bridge_reg(sysbase, BRIDGE_PCIEMEM_BASE0 + i);
+                nlm_write_pci_reg(pciebase, PCIE_BYTE_SWAP_MEM_BASE, reg);
+
+                reg = nlm_read_bridge_reg(sysbase, BRIDGE_PCIEMEM_LIMIT0 + i);
+                nlm_write_pci_reg(pciebase, PCIE_BYTE_SWAP_MEM_LIM,
+                        reg | 0xfff);
+
+                reg = nlm_read_bridge_reg(sysbase, BRIDGE_PCIEIO_BASE0 + i);
+                nlm_write_pci_reg(pciebase, PCIE_BYTE_SWAP_IO_BASE, reg);
+
+                reg = nlm_read_bridge_reg(sysbase, BRIDGE_PCIEIO_LIMIT0 + i);
+                nlm_write_pci_reg(pciebase, PCIE_BYTE_SWAP_IO_LIM, reg | 0xfff);
+        }
+        return 0;
+}
+
+static int __init pcibios_init(void)
+{
+        /* Firmware assigns PCI resources */
+        pci_set_flags(PCI_PROBE_ONLY);
+        pci_config_base = ioremap(XLP_DEFAULT_PCI_ECFG_BASE, 64 << 20);
+
+        /* Extend IO port for memory mapped io */
+        ioport_resource.start =  0;
+        ioport_resource.end   = ~0;
+
+        xlp_enable_pci_bswap();
+        set_io_port_base(CKSEG1);
+        nlm_pci_controller.io_map_base = CKSEG1;
+
+        register_pci_controller(&nlm_pci_controller);
+        pr_info("XLP PCIe Controller %pR%pR.\n", &nlm_pci_io_resource,
+                &nlm_pci_mem_resource);
+
+        return 0;
+}
+arch_initcall(pcibios_init);