PCI: Assign resources before drivers claim devices (pci_scan_root_bus())
Previously, pci_scan_root_bus() created a root PCI bus, enumerated the
devices on it, and called pci_bus_add_devices(), which made the devices
available for drivers to claim them.
Most callers assigned resources to devices after pci_scan_root_bus()
returns, which may be after drivers have claimed the devices. This is
incorrect; the PCI core should not change device resources while a driver
is managing the device.
Remove pci_bus_add_devices() from pci_scan_root_bus() and do it after any
resource assignment in the callers.
Note that ARM's pci_common_init_dev() already called pci_bus_add_devices()
after pci_scan_root_bus(), so we only need to remove the first call:
pci_common_init_dev
pcibios_init_hw
pci_scan_root_bus
pci_bus_add_devices # first call
pci_bus_assign_resources
pci_bus_add_devices # second call
[bhelgaas: changelog, drop "root_bus" var in alpha common_init_pci(),
return failure earlier in mn10300, add "return" in x86 pcibios_scan_root(),
return early if xtensa platform_pcibios_fixup() fails]
Signed-off-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
CC: Richard Henderson <rth@twiddle.net>
CC: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
CC: Matt Turner <mattst88@gmail.com>
CC: David Howells <dhowells@redhat.com>
CC: Tony Luck <tony.luck@intel.com>
CC: Michal Simek <monstr@monstr.eu>
CC: Ralf Baechle <ralf@linux-mips.org>
CC: Koichi Yasutake <yasutake.koichi@jp.panasonic.com>
CC: Sebastian Ott <sebott@linux.vnet.ibm.com>
CC: "David S. Miller" <davem@davemloft.net>
CC: Chris Metcalf <cmetcalf@ezchip.com>
CC: Chris Zankel <chris@zankel.net>
CC: Max Filippov <jcmvbkbc@gmail.com>
CC: Thomas Gleixner <tglx@linutronix.de>
(cherry picked from commit b97ea289cf6aff8d4cbcefe2b707bb9b00a73c73)
Signed-off-by: Alex Shi <alex.shi@linaro.org>
Conflicts solution:
add drivers/pci/host/pci-versatile.c
diff --git a/arch/alpha/kernel/pci.c b/arch/alpha/kernel/pci.c
index 076c35c..f249000 100644
--- a/arch/alpha/kernel/pci.c
+++ b/arch/alpha/kernel/pci.c
@@ -334,6 +334,8 @@
bus = pci_scan_root_bus(NULL, next_busno, alpha_mv.pci_ops,
hose, &resources);
+ if (!bus)
+ continue;
hose->bus = bus;
hose->need_domain_info = need_domain_info;
next_busno = bus->busn_res.end + 1;
@@ -349,6 +351,11 @@
pci_assign_unassigned_resources();
pci_fixup_irqs(alpha_mv.pci_swizzle, alpha_mv.pci_map_irq);
+ for (hose = hose_head; hose; hose = hose->next) {
+ bus = hose->bus;
+ if (bus)
+ pci_bus_add_devices(bus);
+ }
}
diff --git a/arch/frv/mb93090-mb00/pci-vdk.c b/arch/frv/mb93090-mb00/pci-vdk.c
index efa5d65..34fb537 100644
--- a/arch/frv/mb93090-mb00/pci-vdk.c
+++ b/arch/frv/mb93090-mb00/pci-vdk.c
@@ -316,6 +316,7 @@
int __init pcibios_init(void)
{
+ struct pci_bus *bus;
struct pci_ops *dir = NULL;
LIST_HEAD(resources);
@@ -383,12 +384,15 @@
printk("PCI: Probing PCI hardware\n");
pci_add_resource(&resources, &pci_ioport_resource);
pci_add_resource(&resources, &pci_iomem_resource);
- pci_scan_root_bus(NULL, 0, pci_root_ops, NULL, &resources);
+ bus = pci_scan_root_bus(NULL, 0, pci_root_ops, NULL, &resources);
pcibios_irq_init();
pcibios_fixup_irqs();
pcibios_resource_survey();
+ if (!bus)
+ return 0;
+ pci_bus_add_devices(bus);
return 0;
}
diff --git a/arch/ia64/sn/kernel/io_init.c b/arch/ia64/sn/kernel/io_init.c
index 0b5ce82..1be65eb 100644
--- a/arch/ia64/sn/kernel/io_init.c
+++ b/arch/ia64/sn/kernel/io_init.c
@@ -271,7 +271,9 @@
if (bus == NULL) {
kfree(res);
kfree(controller);
+ return;
}
+ pci_bus_add_devices(bus);
}
/*
diff --git a/arch/microblaze/pci/pci-common.c b/arch/microblaze/pci/pci-common.c
index b30e41c..a014e5b 100644
--- a/arch/microblaze/pci/pci-common.c
+++ b/arch/microblaze/pci/pci-common.c
@@ -1371,6 +1371,10 @@
/* Call common code to handle resource allocation */
pcibios_resource_survey();
+ list_for_each_entry_safe(hose, tmp, &hose_list, list_node) {
+ if (hose->bus)
+ pci_bus_add_devices(hose->bus);
+ }
return 0;
}
diff --git a/arch/mips/pci/pci.c b/arch/mips/pci/pci.c
index 1bf60b1..9eb54b5 100644
--- a/arch/mips/pci/pci.c
+++ b/arch/mips/pci/pci.c
@@ -114,6 +114,7 @@
pci_bus_size_bridges(bus);
pci_bus_assign_resources(bus);
}
+ pci_bus_add_devices(bus);
}
}
diff --git a/arch/mn10300/unit-asb2305/pci.c b/arch/mn10300/unit-asb2305/pci.c
index 6b4339f..1d91c74 100644
--- a/arch/mn10300/unit-asb2305/pci.c
+++ b/arch/mn10300/unit-asb2305/pci.c
@@ -347,6 +347,7 @@
{
resource_size_t io_offset, mem_offset;
LIST_HEAD(resources);
+ struct pci_bus *bus;
ioport_resource.start = 0xA0000000;
ioport_resource.end = 0xDFFFFFFF;
@@ -376,11 +377,14 @@
pci_add_resource_offset(&resources, &pci_ioport_resource, io_offset);
pci_add_resource_offset(&resources, &pci_iomem_resource, mem_offset);
- pci_scan_root_bus(NULL, 0, &pci_direct_ampci, NULL, &resources);
+ bus = pci_scan_root_bus(NULL, 0, &pci_direct_ampci, NULL, &resources);
+ if (!bus)
+ return 0;
pcibios_irq_init();
pcibios_fixup_irqs();
pcibios_resource_survey();
+ pci_bus_add_devices(bus);
return 0;
}
diff --git a/arch/s390/pci/pci.c b/arch/s390/pci/pci.c
index d59c825..dda4782 100644
--- a/arch/s390/pci/pci.c
+++ b/arch/s390/pci/pci.c
@@ -755,8 +755,8 @@
zpci_cleanup_bus_resources(zdev);
return -EIO;
}
-
zdev->bus->max_bus_speed = zdev->max_bus_speed;
+ pci_bus_add_devices(zdev->bus);
return 0;
}
diff --git a/arch/sh/drivers/pci/pci.c b/arch/sh/drivers/pci/pci.c
index 1bc09ee..efc1051 100644
--- a/arch/sh/drivers/pci/pci.c
+++ b/arch/sh/drivers/pci/pci.c
@@ -69,6 +69,7 @@
pci_bus_size_bridges(bus);
pci_bus_assign_resources(bus);
+ pci_bus_add_devices(bus);
} else {
pci_free_resource_list(&resources);
}
diff --git a/arch/sparc/kernel/leon_pci.c b/arch/sparc/kernel/leon_pci.c
index 899b720..2971076 100644
--- a/arch/sparc/kernel/leon_pci.c
+++ b/arch/sparc/kernel/leon_pci.c
@@ -40,6 +40,7 @@
/* Assign devices with resources */
pci_assign_unassigned_resources();
+ pci_bus_add_devices(root_bus);
} else {
pci_free_resource_list(&resources);
}
diff --git a/arch/tile/kernel/pci.c b/arch/tile/kernel/pci.c
index 1f80a88..9503957 100644
--- a/arch/tile/kernel/pci.c
+++ b/arch/tile/kernel/pci.c
@@ -339,6 +339,8 @@
struct pci_bus *next_bus;
struct pci_dev *dev;
+ pci_bus_add_devices(root_bus);
+
list_for_each_entry(dev, &root_bus->devices, bus_list) {
/*
* Find the PCI host controller, ie. the 1st
diff --git a/arch/tile/kernel/pci_gx.c b/arch/tile/kernel/pci_gx.c
index e717af20..be79d28 100644
--- a/arch/tile/kernel/pci_gx.c
+++ b/arch/tile/kernel/pci_gx.c
@@ -1042,6 +1042,8 @@
alloc_mem_map_failed:
break;
}
+
+ pci_bus_add_devices(root_bus);
}
return 0;
diff --git a/arch/x86/pci/common.c b/arch/x86/pci/common.c
index 2fb3847..8fd6f44 100644
--- a/arch/x86/pci/common.c
+++ b/arch/x86/pci/common.c
@@ -490,7 +490,9 @@
if (!bus) {
pci_free_resource_list(&resources);
kfree(sd);
+ return;
}
+ pci_bus_add_devices(bus);
}
void __init pcibios_set_cache_line_size(void)
diff --git a/arch/xtensa/kernel/pci.c b/arch/xtensa/kernel/pci.c
index 5b34033..b848cc3 100644
--- a/arch/xtensa/kernel/pci.c
+++ b/arch/xtensa/kernel/pci.c
@@ -174,7 +174,7 @@
struct pci_controller *pci_ctrl;
struct list_head resources;
struct pci_bus *bus;
- int next_busno = 0;
+ int next_busno = 0, ret;
printk("PCI: Probing PCI hardware\n");
@@ -185,14 +185,25 @@
pci_controller_apertures(pci_ctrl, &resources);
bus = pci_scan_root_bus(NULL, pci_ctrl->first_busno,
pci_ctrl->ops, pci_ctrl, &resources);
+ if (!bus)
+ continue;
+
pci_ctrl->bus = bus;
pci_ctrl->last_busno = bus->busn_res.end;
if (next_busno <= pci_ctrl->last_busno)
next_busno = pci_ctrl->last_busno+1;
}
pci_bus_count = next_busno;
+ ret = platform_pcibios_fixup();
+ if (ret)
+ return ret;
- return platform_pcibios_fixup();
+ for (pci_ctrl = pci_ctrl_head; pci_ctrl; pci_ctrl = pci_ctrl->next) {
+ if (pci_ctrl->bus)
+ pci_bus_add_devices(pci_ctrl->bus);
+ }
+
+ return 0;
}
subsys_initcall(pcibios_init);
diff --git a/drivers/pci/host/pci-versatile.c b/drivers/pci/host/pci-versatile.c
new file mode 100644
index 0000000..e3a2450
--- /dev/null
+++ b/drivers/pci/host/pci-versatile.c
@@ -0,0 +1,238 @@
+/*
+ * 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;
+
+ err = of_pci_get_host_bridge_resources(np, 0, 0xff, res, &iobase);
+ if (err)
+ return err;
+
+ resource_list_for_each_entry(win, res, list) {
+ struct resource *parent, *res = win->res;
+
+ switch (resource_type(res)) {
+ case IORESOURCE_IO:
+ parent = &ioport_resource;
+ err = pci_remap_iospace(res, iobase);
+ if (err) {
+ dev_warn(dev, "error %d: failed to map resource %pR\n",
+ err, res);
+ continue;
+ }
+ break;
+ case IORESOURCE_MEM:
+ parent = &iomem_resource;
+ res_valid |= !(res->flags & IORESOURCE_PREFETCH);
+
+ writel(res->start >> 28, PCI_IMAP(mem));
+ writel(PHYS_OFFSET >> 28, PCI_SMAP(mem));
+ mem++;
+
+ break;
+ case IORESOURCE_BUS:
+ default:
+ continue;
+ }
+
+ err = devm_request_resource(dev, parent, res);
+ if (err)
+ goto out_release_res;
+ }
+
+ if (!res_valid) {
+ dev_err(dev, "non-prefetchable memory resource required\n");
+ err = -EINVAL;
+ goto out_release_res;
+ }
+
+ return 0;
+
+out_release_res:
+ pci_free_resource_list(res);
+ return err;
+}
+
+/* Unused, temporary to satisfy ARM arch code */
+struct pci_sys_data sys;
+
+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;
+ LIST_HEAD(pci_res);
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!res)
+ return -ENODEV;
+ versatile_pci_base = devm_ioremap_resource(&pdev->dev, res);
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+ if (!res)
+ return -ENODEV;
+ versatile_cfg_base[0] = devm_ioremap_resource(&pdev->dev, res);
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 2);
+ if (!res)
+ return -ENODEV;
+ versatile_cfg_base[1] = devm_ioremap_resource(&pdev->dev, res);
+
+ 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);
+
+ bus = pci_scan_root_bus(&pdev->dev, 0, &pci_versatile_ops, &sys, &pci_res);
+ if (!bus)
+ return -ENOMEM;
+
+ pci_fixup_irqs(pci_common_swizzle, of_irq_parse_and_map_pci);
+ pci_assign_unassigned_bus_resources(bus);
+ 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,
+ },
+ .probe = versatile_pci_probe,
+};
+module_platform_driver(versatile_pci_driver);
+
+MODULE_DESCRIPTION("Versatile PCI driver");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index 2d49853..073396c 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -2165,7 +2165,6 @@
if (!found)
pci_bus_update_busn_res_end(b, max);
- pci_bus_add_devices(b);
return b;
}
EXPORT_SYMBOL(pci_scan_root_bus);