1 /* 2 * leon_pci.c: LEON Host PCI support 3 * 4 * Copyright (C) 2011 Aeroflex Gaisler AB, Daniel Hellstrom 5 * 6 * Code is partially derived from pcic.c 7 */ 8 9 #include <linux/of_device.h> 10 #include <linux/kernel.h> 11 #include <linux/pci.h> 12 #include <linux/export.h> 13 #include <asm/leon.h> 14 #include <asm/leon_pci.h> 15 16 /* The LEON architecture does not rely on a BIOS or bootloader to setup 17 * PCI for us. The Linux generic routines are used to setup resources, 18 * reset values of configuration-space register settings are preserved. 19 * 20 * PCI Memory and Prefetchable Memory is direct-mapped. However I/O Space is 21 * accessed through a Window which is translated to low 64KB in PCI space, the 22 * first 4KB is not used so 60KB is available. 23 */ 24 void leon_pci_init(struct platform_device *ofdev, struct leon_pci_info *info) 25 { 26 LIST_HEAD(resources); 27 struct pci_bus *root_bus; 28 29 pci_add_resource_offset(&resources, &info->io_space, 30 info->io_space.start - 0x1000); 31 pci_add_resource(&resources, &info->mem_space); 32 info->busn.flags = IORESOURCE_BUS; 33 pci_add_resource(&resources, &info->busn); 34 35 root_bus = pci_scan_root_bus(&ofdev->dev, 0, info->ops, info, 36 &resources); 37 if (!root_bus) { 38 pci_free_resource_list(&resources); 39 return; 40 } 41 42 /* Setup IRQs of all devices using custom routines */ 43 pci_fixup_irqs(pci_common_swizzle, info->map_irq); 44 45 /* Assign devices with resources */ 46 pci_assign_unassigned_resources(); 47 pci_bus_add_devices(root_bus); 48 } 49 50 void pcibios_fixup_bus(struct pci_bus *pbus) 51 { 52 struct pci_dev *dev; 53 int i, has_io, has_mem; 54 u16 cmd; 55 56 list_for_each_entry(dev, &pbus->devices, bus_list) { 57 /* 58 * We can not rely on that the bootloader has enabled I/O 59 * or memory access to PCI devices. Instead we enable it here 60 * if the device has BARs of respective type. 61 */ 62 has_io = has_mem = 0; 63 for (i = 0; i < PCI_ROM_RESOURCE; i++) { 64 unsigned long f = dev->resource[i].flags; 65 if (f & IORESOURCE_IO) 66 has_io = 1; 67 else if (f & IORESOURCE_MEM) 68 has_mem = 1; 69 } 70 /* ROM BARs are mapped into 32-bit memory space */ 71 if (dev->resource[PCI_ROM_RESOURCE].end != 0) { 72 dev->resource[PCI_ROM_RESOURCE].flags |= 73 IORESOURCE_ROM_ENABLE; 74 has_mem = 1; 75 } 76 pci_bus_read_config_word(pbus, dev->devfn, PCI_COMMAND, &cmd); 77 if (has_io && !(cmd & PCI_COMMAND_IO)) { 78 #ifdef CONFIG_PCI_DEBUG 79 printk(KERN_INFO "LEONPCI: Enabling I/O for dev %s\n", 80 pci_name(dev)); 81 #endif 82 cmd |= PCI_COMMAND_IO; 83 pci_bus_write_config_word(pbus, dev->devfn, PCI_COMMAND, 84 cmd); 85 } 86 if (has_mem && !(cmd & PCI_COMMAND_MEMORY)) { 87 #ifdef CONFIG_PCI_DEBUG 88 printk(KERN_INFO "LEONPCI: Enabling MEMORY for dev" 89 "%s\n", pci_name(dev)); 90 #endif 91 cmd |= PCI_COMMAND_MEMORY; 92 pci_bus_write_config_word(pbus, dev->devfn, PCI_COMMAND, 93 cmd); 94 } 95 } 96 } 97 98 resource_size_t pcibios_align_resource(void *data, const struct resource *res, 99 resource_size_t size, resource_size_t align) 100 { 101 return res->start; 102 } 103