arch/arm/mach-kirkwood/pcie.c

   1 /*
   2  * arch/arm/mach-kirkwood/pcie.c
   3  *
   4  * PCIe functions for Marvell Kirkwood SoCs
   5  *
   6  * This file is licensed under the terms of the GNU General Public
   7  * License version 2.  This program is licensed "as is" without any
   8  * warranty of any kind, whether express or implied.
   9  */
  10
  11 #include <linux/kernel.h>
  12 #include <linux/pci.h>
  13 #include <linux/mbus.h>
  14 #include <asm/mach/pci.h>
  15 #include <asm/plat-orion/pcie.h>
  16 #include "common.h"
  17
  18
  19 #define PCIE_BASE       ((void __iomem *)PCIE_VIRT_BASE)
  20
  21 static int pcie_valid_config(int bus, int dev)
  22 {
  23         /*
  24          * Don't go out when trying to access --
  25          * 1. nonexisting device on local bus
  26          * 2. where there's no device connected (no link)
  27          */
  28         if (bus == 0 && dev == 0)
  29                 return 1;
  30
  31         if (!orion_pcie_link_up(PCIE_BASE))
  32                 return 0;
  33
  34         if (bus == 0 && dev != 1)
  35                 return 0;
  36
  37         return 1;
  38 }
  39
  40
  41 /*
  42  * PCIe config cycles are done by programming the PCIE_CONF_ADDR register
  43  * and then reading the PCIE_CONF_DATA register. Need to make sure these
  44  * transactions are atomic.
  45  */
  46 static DEFINE_SPINLOCK(kirkwood_pcie_lock);
  47
  48 static int pcie_rd_conf(struct pci_bus *bus, u32 devfn, int where,
  49                         int size, u32 *val)
  50 {
  51         unsigned long flags;
  52         int ret;
  53
  54         if (pcie_valid_config(bus->number, PCI_SLOT(devfn)) == 0) {
  55                 *val = 0xffffffff;
  56                 return PCIBIOS_DEVICE_NOT_FOUND;
  57         }
  58
  59         spin_lock_irqsave(&kirkwood_pcie_lock, flags);
  60         ret = orion_pcie_rd_conf(PCIE_BASE, bus, devfn, where, size, val);
  61         spin_unlock_irqrestore(&kirkwood_pcie_lock, flags);
  62
  63         return ret;
  64 }
  65
  66 static int pcie_wr_conf(struct pci_bus *bus, u32 devfn,
  67                         int where, int size, u32 val)
  68 {
  69         unsigned long flags;
  70         int ret;
  71
  72         if (pcie_valid_config(bus->number, PCI_SLOT(devfn)) == 0)
  73                 return PCIBIOS_DEVICE_NOT_FOUND;
  74
  75         spin_lock_irqsave(&kirkwood_pcie_lock, flags);
  76         ret = orion_pcie_wr_conf(PCIE_BASE, bus, devfn, where, size, val);
  77         spin_unlock_irqrestore(&kirkwood_pcie_lock, flags);
  78
  79         return ret;
  80 }
  81
  82 static struct pci_ops pcie_ops = {
  83         .read = pcie_rd_conf,
  84         .write = pcie_wr_conf,
  85 };
  86
  87
  88 static int kirkwood_pcie_setup(int nr, struct pci_sys_data *sys)
  89 {
  90         struct resource *res;
  91
  92         /*
  93          * Generic PCIe unit setup.
  94          */
  95         orion_pcie_setup(PCIE_BASE, &kirkwood_mbus_dram_info);
  96
  97         /*
  98          * Request resources.
  99          */
 100         res = kzalloc(sizeof(struct resource) * 2, GFP_KERNEL);
 101         if (!res)
 102                 panic("pcie_setup unable to alloc resources");
 103
 104         /*
 105          * IORESOURCE_IO
 106          */
 107         res[0].name = "PCIe I/O Space";
 108         res[0].flags = IORESOURCE_IO;
 109         res[0].start = KIRKWOOD_PCIE_IO_PHYS_BASE;
 110         res[0].end = res[0].start + KIRKWOOD_PCIE_IO_SIZE - 1;
 111         if (request_resource(&ioport_resource, &res[0]))
 112                 panic("Request PCIe IO resource failed\n");
 113         sys->resource[0] = &res[0];
 114
 115         /*
 116          * IORESOURCE_MEM
 117          */
 118         res[1].name = "PCIe Memory Space";
 119         res[1].flags = IORESOURCE_MEM;
 120         res[1].start = KIRKWOOD_PCIE_MEM_PHYS_BASE;
 121         res[1].end = res[1].start + KIRKWOOD_PCIE_MEM_SIZE - 1;
 122         if (request_resource(&iomem_resource, &res[1]))
 123                 panic("Request PCIe Memory resource failed\n");
 124         sys->resource[1] = &res[1];
 125
 126         sys->resource[2] = NULL;
 127         sys->io_offset = 0;
 128
 129         return 1;
 130 }
 131
 132 static void __devinit rc_pci_fixup(struct pci_dev *dev)
 133 {
 134         /*
 135          * Prevent enumeration of root complex.
 136          */
 137         if (dev->bus->parent == NULL && dev->devfn == 0) {
 138                 int i;
 139
 140                 for (i = 0; i < DEVICE_COUNT_RESOURCE; i++) {
 141                         dev->resource[i].start = 0;
 142                         dev->resource[i].end   = 0;
 143                         dev->resource[i].flags = 0;
 144                 }
 145         }
 146 }
 147 DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_MARVELL, PCI_ANY_ID, rc_pci_fixup);
 148
 149 static struct pci_bus __init *
 150 kirkwood_pcie_scan_bus(int nr, struct pci_sys_data *sys)
 151 {
 152         struct pci_bus *bus;
 153
 154         if (nr == 0) {
 155                 bus = pci_scan_bus(sys->busnr, &pcie_ops, sys);
 156         } else {
 157                 bus = NULL;
 158                 BUG();
 159         }
 160
 161         return bus;
 162 }
 163
 164 static int __init kirkwood_pcie_map_irq(struct pci_dev *dev, u8 slot, u8 pin)
 165 {
 166         return IRQ_KIRKWOOD_PCIE;
 167 }
 168
 169 static struct hw_pci kirkwood_pci __initdata = {
 170         .nr_controllers = 1,
 171         .swizzle        = pci_std_swizzle,
 172         .setup          = kirkwood_pcie_setup,
 173         .scan           = kirkwood_pcie_scan_bus,
 174         .map_irq        = kirkwood_pcie_map_irq,
 175 };
 176
 177 void __init kirkwood_pcie_init(void)
 178 {
 179         pci_common_init(&kirkwood_pci);
 180 }