linux/drivers/pci/host/pci-versatile.c

247 lines
6.8 KiB
C

/*
* Copyright 2004 Koninklijke Philips Electronics NV
*
* Conversion to platform driver and DT:
* Copyright 2014 Linaro Ltd.
*
* This software is licensed under the terms of the GNU General Public
* License version 2, as published by the Free Software Foundation, and
* may be copied, distributed, and modified under those terms.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* 14/04/2005 Initial version, colin.king@philips.com
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of_address.h>
#include <linux/of_pci.h>
#include <linux/of_platform.h>
#include <linux/pci.h>
#include <linux/platform_device.h>
static void __iomem *versatile_pci_base;
static void __iomem *versatile_cfg_base[2];
#define PCI_IMAP(m) (versatile_pci_base + ((m) * 4))
#define PCI_SMAP(m) (versatile_pci_base + 0x14 + ((m) * 4))
#define PCI_SELFID (versatile_pci_base + 0xc)
#define VP_PCI_DEVICE_ID 0x030010ee
#define VP_PCI_CLASS_ID 0x0b400000
static u32 pci_slot_ignore;
static int __init versatile_pci_slot_ignore(char *str)
{
int retval;
int slot;
while ((retval = get_option(&str, &slot))) {
if ((slot < 0) || (slot > 31))
pr_err("Illegal slot value: %d\n", slot);
else
pci_slot_ignore |= (1 << slot);
}
return 1;
}
__setup("pci_slot_ignore=", versatile_pci_slot_ignore);
static void __iomem *versatile_map_bus(struct pci_bus *bus,
unsigned int devfn, int offset)
{
unsigned int busnr = bus->number;
if (pci_slot_ignore & (1 << PCI_SLOT(devfn)))
return NULL;
return versatile_cfg_base[1] + ((busnr << 16) | (devfn << 8) | offset);
}
static struct pci_ops pci_versatile_ops = {
.map_bus = versatile_map_bus,
.read = pci_generic_config_read32,
.write = pci_generic_config_write,
};
static int versatile_pci_parse_request_of_pci_ranges(struct device *dev,
struct list_head *res)
{
int err, mem = 1, res_valid = 0;
struct device_node *np = dev->of_node;
resource_size_t iobase;
struct resource_entry *win, *tmp;
err = of_pci_get_host_bridge_resources(np, 0, 0xff, res, &iobase);
if (err)
return err;
err = devm_request_pci_bus_resources(dev, res);
if (err)
goto out_release_res;
resource_list_for_each_entry_safe(win, tmp, res) {
struct resource *res = win->res;
switch (resource_type(res)) {
case IORESOURCE_IO:
err = pci_remap_iospace(res, iobase);
if (err) {
dev_warn(dev, "error %d: failed to map resource %pR\n",
err, res);
resource_list_destroy_entry(win);
}
break;
case IORESOURCE_MEM:
res_valid |= !(res->flags & IORESOURCE_PREFETCH);
writel(res->start >> 28, PCI_IMAP(mem));
writel(PHYS_OFFSET >> 28, PCI_SMAP(mem));
mem++;
break;
}
}
if (res_valid)
return 0;
dev_err(dev, "non-prefetchable memory resource required\n");
err = -EINVAL;
out_release_res:
pci_free_resource_list(res);
return err;
}
static int versatile_pci_probe(struct platform_device *pdev)
{
struct resource *res;
int ret, i, myslot = -1;
u32 val;
void __iomem *local_pci_cfg_base;
struct pci_bus *bus, *child;
struct pci_host_bridge *bridge;
LIST_HEAD(pci_res);
bridge = devm_pci_alloc_host_bridge(&pdev->dev, 0);
if (!bridge)
return -ENOMEM;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
versatile_pci_base = devm_ioremap_resource(&pdev->dev, res);
if (IS_ERR(versatile_pci_base))
return PTR_ERR(versatile_pci_base);
res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
versatile_cfg_base[0] = devm_ioremap_resource(&pdev->dev, res);
if (IS_ERR(versatile_cfg_base[0]))
return PTR_ERR(versatile_cfg_base[0]);
res = platform_get_resource(pdev, IORESOURCE_MEM, 2);
versatile_cfg_base[1] = devm_pci_remap_cfg_resource(&pdev->dev,
res);
if (IS_ERR(versatile_cfg_base[1]))
return PTR_ERR(versatile_cfg_base[1]);
ret = versatile_pci_parse_request_of_pci_ranges(&pdev->dev, &pci_res);
if (ret)
return ret;
/*
* We need to discover the PCI core first to configure itself
* before the main PCI probing is performed
*/
for (i = 0; i < 32; i++) {
if ((readl(versatile_cfg_base[0] + (i << 11) + PCI_VENDOR_ID) == VP_PCI_DEVICE_ID) &&
(readl(versatile_cfg_base[0] + (i << 11) + PCI_CLASS_REVISION) == VP_PCI_CLASS_ID)) {
myslot = i;
break;
}
}
if (myslot == -1) {
dev_err(&pdev->dev, "Cannot find PCI core!\n");
return -EIO;
}
/*
* Do not to map Versatile FPGA PCI device into memory space
*/
pci_slot_ignore |= (1 << myslot);
dev_info(&pdev->dev, "PCI core found (slot %d)\n", myslot);
writel(myslot, PCI_SELFID);
local_pci_cfg_base = versatile_cfg_base[1] + (myslot << 11);
val = readl(local_pci_cfg_base + PCI_COMMAND);
val |= PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER | PCI_COMMAND_INVALIDATE;
writel(val, local_pci_cfg_base + PCI_COMMAND);
/*
* Configure the PCI inbound memory windows to be 1:1 mapped to SDRAM
*/
writel(PHYS_OFFSET, local_pci_cfg_base + PCI_BASE_ADDRESS_0);
writel(PHYS_OFFSET, local_pci_cfg_base + PCI_BASE_ADDRESS_1);
writel(PHYS_OFFSET, local_pci_cfg_base + PCI_BASE_ADDRESS_2);
/*
* For many years the kernel and QEMU were symbiotically buggy
* in that they both assumed the same broken IRQ mapping.
* QEMU therefore attempts to auto-detect old broken kernels
* so that they still work on newer QEMU as they did on old
* QEMU. Since we now use the correct (ie matching-hardware)
* IRQ mapping we write a definitely different value to a
* PCI_INTERRUPT_LINE register to tell QEMU that we expect
* real hardware behaviour and it need not be backwards
* compatible for us. This write is harmless on real hardware.
*/
writel(0, versatile_cfg_base[0] + PCI_INTERRUPT_LINE);
pci_add_flags(PCI_ENABLE_PROC_DOMAINS);
pci_add_flags(PCI_REASSIGN_ALL_BUS | PCI_REASSIGN_ALL_RSRC);
list_splice_init(&pci_res, &bridge->windows);
bridge->dev.parent = &pdev->dev;
bridge->sysdata = NULL;
bridge->busnr = 0;
bridge->ops = &pci_versatile_ops;
ret = pci_scan_root_bus_bridge(bridge);
if (ret < 0)
return ret;
bus = bridge->bus;
pci_fixup_irqs(pci_common_swizzle, of_irq_parse_and_map_pci);
pci_assign_unassigned_bus_resources(bus);
list_for_each_entry(child, &bus->children, node)
pcie_bus_configure_settings(child);
pci_bus_add_devices(bus);
return 0;
}
static const struct of_device_id versatile_pci_of_match[] = {
{ .compatible = "arm,versatile-pci", },
{ },
};
MODULE_DEVICE_TABLE(of, versatile_pci_of_match);
static struct platform_driver versatile_pci_driver = {
.driver = {
.name = "versatile-pci",
.of_match_table = versatile_pci_of_match,
.suppress_bind_attrs = true,
},
.probe = versatile_pci_probe,
};
module_platform_driver(versatile_pci_driver);
MODULE_DESCRIPTION("Versatile PCI driver");
MODULE_LICENSE("GPL v2");