diff options
Diffstat (limited to 'arch/sparc/kernel/leon_pci.c')
-rw-r--r-- | arch/sparc/kernel/leon_pci.c | 89 |
1 files changed, 89 insertions, 0 deletions
diff --git a/arch/sparc/kernel/leon_pci.c b/arch/sparc/kernel/leon_pci.c new file mode 100644 index 0000000000..8de6646e9c --- /dev/null +++ b/arch/sparc/kernel/leon_pci.c @@ -0,0 +1,89 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * leon_pci.c: LEON Host PCI support + * + * Copyright (C) 2011 Aeroflex Gaisler AB, Daniel Hellstrom + * + * Code is partially derived from pcic.c + */ + +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/kernel.h> +#include <linux/pci.h> +#include <linux/export.h> +#include <asm/leon.h> +#include <asm/leon_pci.h> + +/* The LEON architecture does not rely on a BIOS or bootloader to setup + * PCI for us. The Linux generic routines are used to setup resources, + * reset values of configuration-space register settings are preserved. + * + * PCI Memory and Prefetchable Memory is direct-mapped. However I/O Space is + * accessed through a Window which is translated to low 64KB in PCI space, the + * first 4KB is not used so 60KB is available. + */ +void leon_pci_init(struct platform_device *ofdev, struct leon_pci_info *info) +{ + LIST_HEAD(resources); + struct pci_bus *root_bus; + struct pci_host_bridge *bridge; + int ret; + + bridge = pci_alloc_host_bridge(0); + if (!bridge) + return; + + pci_add_resource_offset(&resources, &info->io_space, + info->io_space.start - 0x1000); + pci_add_resource(&resources, &info->mem_space); + info->busn.flags = IORESOURCE_BUS; + pci_add_resource(&resources, &info->busn); + + list_splice_init(&resources, &bridge->windows); + bridge->dev.parent = &ofdev->dev; + bridge->sysdata = info; + bridge->busnr = 0; + bridge->ops = info->ops; + bridge->swizzle_irq = pci_common_swizzle; + bridge->map_irq = info->map_irq; + + ret = pci_scan_root_bus_bridge(bridge); + if (ret) { + pci_free_host_bridge(bridge); + return; + } + + root_bus = bridge->bus; + + /* Assign devices with resources */ + pci_assign_unassigned_resources(); + pci_bus_add_devices(root_bus); +} + +int pcibios_enable_device(struct pci_dev *dev, int mask) +{ + struct resource *res; + u16 cmd, oldcmd; + int i; + + pci_read_config_word(dev, PCI_COMMAND, &cmd); + oldcmd = cmd; + + pci_dev_for_each_resource(dev, res, i) { + /* Only set up the requested stuff */ + if (!(mask & (1<<i))) + continue; + + if (res->flags & IORESOURCE_IO) + cmd |= PCI_COMMAND_IO; + if (res->flags & IORESOURCE_MEM) + cmd |= PCI_COMMAND_MEMORY; + } + + if (cmd != oldcmd) { + pci_info(dev, "enabling device (%04x -> %04x)\n", oldcmd, cmd); + pci_write_config_word(dev, PCI_COMMAND, cmd); + } + return 0; +} |