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-rw-r--r--drivers/pci/pci.c397
1 files changed, 327 insertions, 70 deletions
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index e1b0bbd05fa3..e6f7ba4378ba 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -23,7 +23,6 @@
#include <linux/string.h>
#include <linux/log2.h>
#include <linux/logic_pio.h>
-#include <linux/pci-aspm.h>
#include <linux/pm_wakeup.h>
#include <linux/interrupt.h>
#include <linux/device.h>
@@ -194,6 +193,168 @@ void __iomem *pci_ioremap_wc_bar(struct pci_dev *pdev, int bar)
EXPORT_SYMBOL_GPL(pci_ioremap_wc_bar);
#endif
+/**
+ * pci_dev_str_match_path - test if a path string matches a device
+ * @dev: the PCI device to test
+ * @p: string to match the device against
+ * @endptr: pointer to the string after the match
+ *
+ * Test if a string (typically from a kernel parameter) formatted as a
+ * path of device/function addresses matches a PCI device. The string must
+ * be of the form:
+ *
+ * [<domain>:]<bus>:<device>.<func>[/<device>.<func>]*
+ *
+ * A path for a device can be obtained using 'lspci -t'. Using a path
+ * is more robust against bus renumbering than using only a single bus,
+ * device and function address.
+ *
+ * Returns 1 if the string matches the device, 0 if it does not and
+ * a negative error code if it fails to parse the string.
+ */
+static int pci_dev_str_match_path(struct pci_dev *dev, const char *path,
+ const char **endptr)
+{
+ int ret;
+ int seg, bus, slot, func;
+ char *wpath, *p;
+ char end;
+
+ *endptr = strchrnul(path, ';');
+
+ wpath = kmemdup_nul(path, *endptr - path, GFP_KERNEL);
+ if (!wpath)
+ return -ENOMEM;
+
+ while (1) {
+ p = strrchr(wpath, '/');
+ if (!p)
+ break;
+ ret = sscanf(p, "/%x.%x%c", &slot, &func, &end);
+ if (ret != 2) {
+ ret = -EINVAL;
+ goto free_and_exit;
+ }
+
+ if (dev->devfn != PCI_DEVFN(slot, func)) {
+ ret = 0;
+ goto free_and_exit;
+ }
+
+ /*
+ * Note: we don't need to get a reference to the upstream
+ * bridge because we hold a reference to the top level
+ * device which should hold a reference to the bridge,
+ * and so on.
+ */
+ dev = pci_upstream_bridge(dev);
+ if (!dev) {
+ ret = 0;
+ goto free_and_exit;
+ }
+
+ *p = 0;
+ }
+
+ ret = sscanf(wpath, "%x:%x:%x.%x%c", &seg, &bus, &slot,
+ &func, &end);
+ if (ret != 4) {
+ seg = 0;
+ ret = sscanf(wpath, "%x:%x.%x%c", &bus, &slot, &func, &end);
+ if (ret != 3) {
+ ret = -EINVAL;
+ goto free_and_exit;
+ }
+ }
+
+ ret = (seg == pci_domain_nr(dev->bus) &&
+ bus == dev->bus->number &&
+ dev->devfn == PCI_DEVFN(slot, func));
+
+free_and_exit:
+ kfree(wpath);
+ return ret;
+}
+
+/**
+ * pci_dev_str_match - test if a string matches a device
+ * @dev: the PCI device to test
+ * @p: string to match the device against
+ * @endptr: pointer to the string after the match
+ *
+ * Test if a string (typically from a kernel parameter) matches a specified
+ * PCI device. The string may be of one of the following formats:
+ *
+ * [<domain>:]<bus>:<device>.<func>[/<device>.<func>]*
+ * pci:<vendor>:<device>[:<subvendor>:<subdevice>]
+ *
+ * The first format specifies a PCI bus/device/function address which
+ * may change if new hardware is inserted, if motherboard firmware changes,
+ * or due to changes caused in kernel parameters. If the domain is
+ * left unspecified, it is taken to be 0. In order to be robust against
+ * bus renumbering issues, a path of PCI device/function numbers may be used
+ * to address the specific device. The path for a device can be determined
+ * through the use of 'lspci -t'.
+ *
+ * The second format matches devices using IDs in the configuration
+ * space which may match multiple devices in the system. A value of 0
+ * for any field will match all devices. (Note: this differs from
+ * in-kernel code that uses PCI_ANY_ID which is ~0; this is for
+ * legacy reasons and convenience so users don't have to specify
+ * FFFFFFFFs on the command line.)
+ *
+ * Returns 1 if the string matches the device, 0 if it does not and
+ * a negative error code if the string cannot be parsed.
+ */
+static int pci_dev_str_match(struct pci_dev *dev, const char *p,
+ const char **endptr)
+{
+ int ret;
+ int count;
+ unsigned short vendor, device, subsystem_vendor, subsystem_device;
+
+ if (strncmp(p, "pci:", 4) == 0) {
+ /* PCI vendor/device (subvendor/subdevice) IDs are specified */
+ p += 4;
+ ret = sscanf(p, "%hx:%hx:%hx:%hx%n", &vendor, &device,
+ &subsystem_vendor, &subsystem_device, &count);
+ if (ret != 4) {
+ ret = sscanf(p, "%hx:%hx%n", &vendor, &device, &count);
+ if (ret != 2)
+ return -EINVAL;
+
+ subsystem_vendor = 0;
+ subsystem_device = 0;
+ }
+
+ p += count;
+
+ if ((!vendor || vendor == dev->vendor) &&
+ (!device || device == dev->device) &&
+ (!subsystem_vendor ||
+ subsystem_vendor == dev->subsystem_vendor) &&
+ (!subsystem_device ||
+ subsystem_device == dev->subsystem_device))
+ goto found;
+ } else {
+ /*
+ * PCI Bus, Device, Function IDs are specified
+ * (optionally, may include a path of devfns following it)
+ */
+ ret = pci_dev_str_match_path(dev, p, &p);
+ if (ret < 0)
+ return ret;
+ else if (ret)
+ goto found;
+ }
+
+ *endptr = p;
+ return 0;
+
+found:
+ *endptr = p;
+ return 1;
+}
static int __pci_find_next_cap_ttl(struct pci_bus *bus, unsigned int devfn,
u8 pos, int cap, int *ttl)
@@ -2076,6 +2237,7 @@ static pci_power_t pci_target_state(struct pci_dev *dev, bool wakeup)
case PCI_D2:
if (pci_no_d1d2(dev))
break;
+ /* else: fall through */
default:
target_state = state;
}
@@ -2321,7 +2483,7 @@ void pci_config_pm_runtime_put(struct pci_dev *pdev)
* @bridge: Bridge to check
*
* This function checks if it is possible to move the bridge to D3.
- * Currently we only allow D3 for recent enough PCIe ports.
+ * Currently we only allow D3 for recent enough PCIe ports and Thunderbolt.
*/
bool pci_bridge_d3_possible(struct pci_dev *bridge)
{
@@ -2336,18 +2498,27 @@ bool pci_bridge_d3_possible(struct pci_dev *bridge)
return false;
/*
- * Hotplug interrupts cannot be delivered if the link is down,
- * so parents of a hotplug port must stay awake. In addition,
- * hotplug ports handled by firmware in System Management Mode
+ * Hotplug ports handled by firmware in System Management Mode
* may not be put into D3 by the OS (Thunderbolt on non-Macs).
- * For simplicity, disallow in general for now.
*/
- if (bridge->is_hotplug_bridge)
+ if (bridge->is_hotplug_bridge && !pciehp_is_native(bridge))
return false;
if (pci_bridge_d3_force)
return true;
+ /* Even the oldest 2010 Thunderbolt controller supports D3. */
+ if (bridge->is_thunderbolt)
+ return true;
+
+ /*
+ * Hotplug ports handled natively by the OS were not validated
+ * by vendors for runtime D3 at least until 2018 because there
+ * was no OS support.
+ */
+ if (bridge->is_hotplug_bridge)
+ return false;
+
/*
* It should be safe to put PCIe ports from 2015 or newer
* to D3.
@@ -2851,6 +3022,66 @@ void pci_request_acs(void)
pci_acs_enable = 1;
}
+static const char *disable_acs_redir_param;
+
+/**
+ * pci_disable_acs_redir - disable ACS redirect capabilities
+ * @dev: the PCI device
+ *
+ * For only devices specified in the disable_acs_redir parameter.
+ */
+static void pci_disable_acs_redir(struct pci_dev *dev)
+{
+ int ret = 0;
+ const char *p;
+ int pos;
+ u16 ctrl;
+
+ if (!disable_acs_redir_param)
+ return;
+
+ p = disable_acs_redir_param;
+ while (*p) {
+ ret = pci_dev_str_match(dev, p, &p);
+ if (ret < 0) {
+ pr_info_once("PCI: Can't parse disable_acs_redir parameter: %s\n",
+ disable_acs_redir_param);
+
+ break;
+ } else if (ret == 1) {
+ /* Found a match */
+ break;
+ }
+
+ if (*p != ';' && *p != ',') {
+ /* End of param or invalid format */
+ break;
+ }
+ p++;
+ }
+
+ if (ret != 1)
+ return;
+
+ if (!pci_dev_specific_disable_acs_redir(dev))
+ return;
+
+ pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ACS);
+ if (!pos) {
+ pci_warn(dev, "cannot disable ACS redirect for this hardware as it does not have ACS capabilities\n");
+ return;
+ }
+
+ pci_read_config_word(dev, pos + PCI_ACS_CTRL, &ctrl);
+
+ /* P2P Request & Completion Redirect */
+ ctrl &= ~(PCI_ACS_RR | PCI_ACS_CR | PCI_ACS_EC);
+
+ pci_write_config_word(dev, pos + PCI_ACS_CTRL, ctrl);
+
+ pci_info(dev, "disabled ACS redirect\n");
+}
+
/**
* pci_std_enable_acs - enable ACS on devices using standard ACS capabilites
* @dev: the PCI device
@@ -2890,12 +3121,22 @@ static void pci_std_enable_acs(struct pci_dev *dev)
void pci_enable_acs(struct pci_dev *dev)
{
if (!pci_acs_enable)
- return;
+ goto disable_acs_redir;
if (!pci_dev_specific_enable_acs(dev))
- return;
+ goto disable_acs_redir;
pci_std_enable_acs(dev);
+
+disable_acs_redir:
+ /*
+ * Note: pci_disable_acs_redir() must be called even if ACS was not
+ * enabled by the kernel because it may have been enabled by
+ * platform firmware. So if we are told to disable it, we should
+ * always disable it after setting the kernel's default
+ * preferences.
+ */
+ pci_disable_acs_redir(dev);
}
static bool pci_acs_flags_enabled(struct pci_dev *pdev, u16 acs_flags)
@@ -3610,6 +3851,44 @@ void pci_unmap_iospace(struct resource *res)
}
EXPORT_SYMBOL(pci_unmap_iospace);
+static void devm_pci_unmap_iospace(struct device *dev, void *ptr)
+{
+ struct resource **res = ptr;
+
+ pci_unmap_iospace(*res);
+}
+
+/**
+ * devm_pci_remap_iospace - Managed pci_remap_iospace()
+ * @dev: Generic device to remap IO address for
+ * @res: Resource describing the I/O space
+ * @phys_addr: physical address of range to be mapped
+ *
+ * Managed pci_remap_iospace(). Map is automatically unmapped on driver
+ * detach.
+ */
+int devm_pci_remap_iospace(struct device *dev, const struct resource *res,
+ phys_addr_t phys_addr)
+{
+ const struct resource **ptr;
+ int error;
+
+ ptr = devres_alloc(devm_pci_unmap_iospace, sizeof(*ptr), GFP_KERNEL);
+ if (!ptr)
+ return -ENOMEM;
+
+ error = pci_remap_iospace(res, phys_addr);
+ if (error) {
+ devres_free(ptr);
+ } else {
+ *ptr = res;
+ devres_add(dev, ptr);
+ }
+
+ return error;
+}
+EXPORT_SYMBOL(devm_pci_remap_iospace);
+
/**
* devm_pci_remap_cfgspace - Managed pci_remap_cfgspace()
* @dev: Generic device to remap IO address for
@@ -5295,14 +5574,16 @@ u32 pcie_bandwidth_capable(struct pci_dev *dev, enum pci_bus_speed *speed,
}
/**
- * pcie_print_link_status - Report the PCI device's link speed and width
+ * __pcie_print_link_status - Report the PCI device's link speed and width
* @dev: PCI device to query
+ * @verbose: Print info even when enough bandwidth is available
*
- * Report the available bandwidth at the device. If this is less than the
- * device is capable of, report the device's maximum possible bandwidth and
- * the upstream link that limits its performance to less than that.
+ * If the available bandwidth at the device is less than the device is
+ * capable of, report the device's maximum possible bandwidth and the
+ * upstream link that limits its performance. If @verbose, always print
+ * the available bandwidth, even if the device isn't constrained.
*/
-void pcie_print_link_status(struct pci_dev *dev)
+void __pcie_print_link_status(struct pci_dev *dev, bool verbose)
{
enum pcie_link_width width, width_cap;
enum pci_bus_speed speed, speed_cap;
@@ -5312,11 +5593,11 @@ void pcie_print_link_status(struct pci_dev *dev)
bw_cap = pcie_bandwidth_capable(dev, &speed_cap, &width_cap);
bw_avail = pcie_bandwidth_available(dev, &limiting_dev, &speed, &width);
- if (bw_avail >= bw_cap)
+ if (bw_avail >= bw_cap && verbose)
pci_info(dev, "%u.%03u Gb/s available PCIe bandwidth (%s x%d link)\n",
bw_cap / 1000, bw_cap % 1000,
PCIE_SPEED2STR(speed_cap), width_cap);
- else
+ else if (bw_avail < bw_cap)
pci_info(dev, "%u.%03u Gb/s available PCIe bandwidth, limited by %s x%d link at %s (capable of %u.%03u Gb/s with %s x%d link)\n",
bw_avail / 1000, bw_avail % 1000,
PCIE_SPEED2STR(speed), width,
@@ -5324,6 +5605,17 @@ void pcie_print_link_status(struct pci_dev *dev)
bw_cap / 1000, bw_cap % 1000,
PCIE_SPEED2STR(speed_cap), width_cap);
}
+
+/**
+ * pcie_print_link_status - Report the PCI device's link speed and width
+ * @dev: PCI device to query
+ *
+ * Report the available bandwidth at the device.
+ */
+void pcie_print_link_status(struct pci_dev *dev)
+{
+ __pcie_print_link_status(dev, true);
+}
EXPORT_SYMBOL(pcie_print_link_status);
/**
@@ -5485,10 +5777,10 @@ static DEFINE_SPINLOCK(resource_alignment_lock);
static resource_size_t pci_specified_resource_alignment(struct pci_dev *dev,
bool *resize)
{
- int seg, bus, slot, func, align_order, count;
- unsigned short vendor, device, subsystem_vendor, subsystem_device;
+ int align_order, count;
resource_size_t align = pcibios_default_alignment();
- char *p;
+ const char *p;
+ int ret;
spin_lock(&resource_alignment_lock);
p = resource_alignment_param;
@@ -5508,58 +5800,21 @@ static resource_size_t pci_specified_resource_alignment(struct pci_dev *dev,
} else {
align_order = -1;
}
- if (strncmp(p, "pci:", 4) == 0) {
- /* PCI vendor/device (subvendor/subdevice) ids are specified */
- p += 4;
- if (sscanf(p, "%hx:%hx:%hx:%hx%n",
- &vendor, &device, &subsystem_vendor, &subsystem_device, &count) != 4) {
- if (sscanf(p, "%hx:%hx%n", &vendor, &device, &count) != 2) {
- printk(KERN_ERR "PCI: Can't parse resource_alignment parameter: pci:%s\n",
- p);
- break;
- }
- subsystem_vendor = subsystem_device = 0;
- }
- p += count;
- if ((!vendor || (vendor == dev->vendor)) &&
- (!device || (device == dev->device)) &&
- (!subsystem_vendor || (subsystem_vendor == dev->subsystem_vendor)) &&
- (!subsystem_device || (subsystem_device == dev->subsystem_device))) {
- *resize = true;
- if (align_order == -1)
- align = PAGE_SIZE;
- else
- align = 1 << align_order;
- /* Found */
- break;
- }
- }
- else {
- if (sscanf(p, "%x:%x:%x.%x%n",
- &seg, &bus, &slot, &func, &count) != 4) {
- seg = 0;
- if (sscanf(p, "%x:%x.%x%n",
- &bus, &slot, &func, &count) != 3) {
- /* Invalid format */
- printk(KERN_ERR "PCI: Can't parse resource_alignment parameter: %s\n",
- p);
- break;
- }
- }
- p += count;
- if (seg == pci_domain_nr(dev->bus) &&
- bus == dev->bus->number &&
- slot == PCI_SLOT(dev->devfn) &&
- func == PCI_FUNC(dev->devfn)) {
- *resize = true;
- if (align_order == -1)
- align = PAGE_SIZE;
- else
- align = 1 << align_order;
- /* Found */
- break;
- }
+
+ ret = pci_dev_str_match(dev, p, &p);
+ if (ret == 1) {
+ *resize = true;
+ if (align_order == -1)
+ align = PAGE_SIZE;
+ else
+ align = 1 << align_order;
+ break;
+ } else if (ret < 0) {
+ pr_err("PCI: Can't parse resource_alignment parameter: %s\n",
+ p);
+ break;
}
+
if (*p != ';' && *p != ',') {
/* End of param or invalid format */
break;
@@ -5874,6 +6129,8 @@ static int __init pci_setup(char *str)
pcie_bus_config = PCIE_BUS_PEER2PEER;
} else if (!strncmp(str, "pcie_scan_all", 13)) {
pci_add_flags(PCI_SCAN_ALL_PCIE_DEVS);
+ } else if (!strncmp(str, "disable_acs_redir=", 18)) {
+ disable_acs_redir_param = str + 18;
} else {
printk(KERN_ERR "PCI: Unknown option `%s'\n",
str);
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