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 /* Setup IRQs of all devices using custom routines */ 39 pci_fixup_irqs(pci_common_swizzle, info->map_irq); 40 41 /* Assign devices with resources */ 42 pci_assign_unassigned_resources(); 43 } else { 44 pci_free_resource_list(&resources); 45 } 46 } 47 48 void pcibios_fixup_bus(struct pci_bus *pbus) 49 { 50 struct pci_dev *dev; 51 int i, has_io, has_mem; 52 u16 cmd; 53 54 list_for_each_entry(dev, &pbus->devices, bus_list) { 55 /* 56 * We can not rely on that the bootloader has enabled I/O 57 * or memory access to PCI devices. Instead we enable it here 58 * if the device has BARs of respective type. 59 */ 60 has_io = has_mem = 0; 61 for (i = 0; i < PCI_ROM_RESOURCE; i++) { 62 unsigned long f = dev->resource[i].flags; 63 if (f & IORESOURCE_IO) 64 has_io = 1; 65 else if (f & IORESOURCE_MEM) 66 has_mem = 1; 67 } 68 /* ROM BARs are mapped into 32-bit memory space */ 69 if (dev->resource[PCI_ROM_RESOURCE].end != 0) { 70 dev->resource[PCI_ROM_RESOURCE].flags |= 71 IORESOURCE_ROM_ENABLE; 72 has_mem = 1; 73 } 74 pci_bus_read_config_word(pbus, dev->devfn, PCI_COMMAND, &cmd); 75 if (has_io && !(cmd & PCI_COMMAND_IO)) { 76 #ifdef CONFIG_PCI_DEBUG 77 printk(KERN_INFO "LEONPCI: Enabling I/O for dev %s\n", 78 pci_name(dev)); 79 #endif 80 cmd |= PCI_COMMAND_IO; 81 pci_bus_write_config_word(pbus, dev->devfn, PCI_COMMAND, 82 cmd); 83 } 84 if (has_mem && !(cmd & PCI_COMMAND_MEMORY)) { 85 #ifdef CONFIG_PCI_DEBUG 86 printk(KERN_INFO "LEONPCI: Enabling MEMORY for dev" 87 "%s\n", pci_name(dev)); 88 #endif 89 cmd |= PCI_COMMAND_MEMORY; 90 pci_bus_write_config_word(pbus, dev->devfn, PCI_COMMAND, 91 cmd); 92 } 93 } 94 } 95 96 resource_size_t pcibios_align_resource(void *data, const struct resource *res, 97 resource_size_t size, resource_size_t align) 98 { 99 return res->start; 100 } 101