8. Vendor and device identifications
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-One is not required to add new device ids to include/linux/pci_ids.h.
-Please add PCI_VENDOR_ID_xxx for vendors and a hex constant for device ids.
+Do not add new device or vendor IDs to include/linux/pci_ids.h unless they
+are shared across multiple drivers. You can add private definitions in
+your driver if they're helpful, or just use plain hex constants.
-PCI_VENDOR_ID_xxx constants are re-used. The device ids are arbitrary
-hex numbers (vendor controlled) and normally used only in a single
-location, the pci_device_id table.
+The device IDs are arbitrary hex numbers (vendor controlled) and normally used
+only in a single location, the pci_device_id table.
-Please DO submit new vendor/device ids to pciids.sourceforge.net project.
+Please DO submit new vendor/device IDs to http://pciids.sourceforge.net/.
}
EXPORT_SYMBOL(acpi_pci_osc_control_set);
-static void negotiate_os_control(struct acpi_pci_root *root, int *no_aspm,
- int *clear_aspm)
+static void negotiate_os_control(struct acpi_pci_root *root, int *no_aspm)
{
u32 support, control, requested;
acpi_status status;
decode_osc_control(root, "OS now controls", control);
if (acpi_gbl_FADT.boot_flags & ACPI_FADT_NO_ASPM) {
/*
- * We have ASPM control, but the FADT indicates
- * that it's unsupported. Clear it.
+ * We have ASPM control, but the FADT indicates that
+ * it's unsupported. Leave existing configuration
+ * intact and prevent the OS from touching it.
*/
- *clear_aspm = 1;
+ dev_info(&device->dev, "FADT indicates ASPM is unsupported, using BIOS configuration\n");
+ *no_aspm = 1;
}
} else {
decode_osc_control(root, "OS requested", requested);
int result;
struct acpi_pci_root *root;
acpi_handle handle = device->handle;
- int no_aspm = 0, clear_aspm = 0;
+ int no_aspm = 0;
bool hotadd = system_state != SYSTEM_BOOTING;
root = kzalloc(sizeof(struct acpi_pci_root), GFP_KERNEL);
root->mcfg_addr = acpi_pci_root_get_mcfg_addr(handle);
- negotiate_os_control(root, &no_aspm, &clear_aspm);
+ negotiate_os_control(root, &no_aspm);
/*
* TBD: Need PCI interface for enumeration/configuration of roots.
goto remove_dmar;
}
- if (clear_aspm) {
- dev_info(&device->dev, "Disabling ASPM (FADT indicates it is unsupported)\n");
- pcie_clear_aspm(root->bus);
- }
if (no_aspm)
pcie_no_aspm();
return bus;
}
-static struct pci_host_bridge *find_pci_host_bridge(struct pci_bus *bus)
+struct pci_host_bridge *pci_find_host_bridge(struct pci_bus *bus)
{
struct pci_bus *root_bus = find_pci_root_bus(bus);
void pcibios_resource_to_bus(struct pci_bus *bus, struct pci_bus_region *region,
struct resource *res)
{
- struct pci_host_bridge *bridge = find_pci_host_bridge(bus);
+ struct pci_host_bridge *bridge = pci_find_host_bridge(bus);
struct resource_entry *window;
resource_size_t offset = 0;
void pcibios_bus_to_resource(struct pci_bus *bus, struct resource *res,
struct pci_bus_region *region)
{
- struct pci_host_bridge *bridge = find_pci_host_bridge(bus);
+ struct pci_host_bridge *bridge = pci_find_host_bridge(bus);
struct resource_entry *window;
resource_size_t offset = 0;
#include <linux/pm_qos.h>
#include "pci.h"
+/*
+ * The UUID is defined in the PCI Firmware Specification available here:
+ * https://www.pcisig.com/members/downloads/pcifw_r3_1_13Dec10.pdf
+ */
+const u8 pci_acpi_dsm_uuid[] = {
+ 0xd0, 0x37, 0xc9, 0xe5, 0x53, 0x35, 0x7a, 0x4d,
+ 0x91, 0x17, 0xea, 0x4d, 0x19, 0xc3, 0x43, 0x4d
+};
+
phys_addr_t acpi_pci_root_get_mcfg_addr(acpi_handle handle)
{
acpi_status status = AE_NOT_EXIST;
void acpi_pci_add_bus(struct pci_bus *bus)
{
+ union acpi_object *obj;
+ struct pci_host_bridge *bridge;
+
if (acpi_pci_disabled || !bus->bridge)
return;
acpi_pci_slot_enumerate(bus);
acpiphp_enumerate_slots(bus);
+
+ /*
+ * For a host bridge, check its _DSM for function 8 and if
+ * that is available, mark it in pci_host_bridge.
+ */
+ if (!pci_is_root_bus(bus))
+ return;
+
+ obj = acpi_evaluate_dsm(ACPI_HANDLE(bus->bridge), pci_acpi_dsm_uuid, 3,
+ RESET_DELAY_DSM, NULL);
+ if (!obj)
+ return;
+
+ if (obj->type == ACPI_TYPE_INTEGER && obj->integer.value == 1) {
+ bridge = pci_find_host_bridge(bus);
+ bridge->ignore_reset_delay = 1;
+ }
+ ACPI_FREE(obj);
}
void acpi_pci_remove_bus(struct pci_bus *bus)
check_children);
}
+/**
+ * pci_acpi_optimize_delay - optimize PCI D3 and D3cold delay from ACPI
+ * @pdev: the PCI device whose delay is to be updated
+ * @adev: the companion ACPI device of this PCI device
+ *
+ * Update the d3_delay and d3cold_delay of a PCI device from the ACPI _DSM
+ * control method of either the device itself or the PCI host bridge.
+ *
+ * Function 8, "Reset Delay," applies to the entire hierarchy below a PCI
+ * host bridge. If it returns one, the OS may assume that all devices in
+ * the hierarchy have already completed power-on reset delays.
+ *
+ * Function 9, "Device Readiness Durations," applies only to the object
+ * where it is located. It returns delay durations required after various
+ * events if the device requires less time than the spec requires. Delays
+ * from this function take precedence over the Reset Delay function.
+ *
+ * These _DSM functions are defined by the draft ECN of January 28, 2014,
+ * titled "ACPI additions for FW latency optimizations."
+ */
+static void pci_acpi_optimize_delay(struct pci_dev *pdev,
+ acpi_handle handle)
+{
+ struct pci_host_bridge *bridge = pci_find_host_bridge(pdev->bus);
+ int value;
+ union acpi_object *obj, *elements;
+
+ if (bridge->ignore_reset_delay)
+ pdev->d3cold_delay = 0;
+
+ obj = acpi_evaluate_dsm(handle, pci_acpi_dsm_uuid, 3,
+ FUNCTION_DELAY_DSM, NULL);
+ if (!obj)
+ return;
+
+ if (obj->type == ACPI_TYPE_PACKAGE && obj->package.count == 5) {
+ elements = obj->package.elements;
+ if (elements[0].type == ACPI_TYPE_INTEGER) {
+ value = (int)elements[0].integer.value / 1000;
+ if (value < PCI_PM_D3COLD_WAIT)
+ pdev->d3cold_delay = value;
+ }
+ if (elements[3].type == ACPI_TYPE_INTEGER) {
+ value = (int)elements[3].integer.value / 1000;
+ if (value < PCI_PM_D3_WAIT)
+ pdev->d3_delay = value;
+ }
+ }
+ ACPI_FREE(obj);
+}
+
static void pci_acpi_setup(struct device *dev)
{
struct pci_dev *pci_dev = to_pci_dev(dev);
if (!adev)
return;
+ pci_acpi_optimize_delay(pci_dev, adev->handle);
+
pci_acpi_add_pm_notifier(adev, pci_dev);
if (!adev->wakeup.flags.valid)
return;
#include <linux/pci-acpi.h>
#include "pci.h"
-#define DEVICE_LABEL_DSM 0x07
-
#ifdef CONFIG_DMI
enum smbios_attr_enum {
SMBIOS_ATTR_NONE = 0,
#endif
#ifdef CONFIG_ACPI
-static const char device_label_dsm_uuid[] = {
- 0xD0, 0x37, 0xC9, 0xE5, 0x53, 0x35, 0x7A, 0x4D,
- 0x91, 0x17, 0xEA, 0x4D, 0x19, 0xC3, 0x43, 0x4D
-};
-
enum acpi_attr_enum {
ACPI_ATTR_LABEL_SHOW,
ACPI_ATTR_INDEX_SHOW,
if (!handle)
return -1;
- obj = acpi_evaluate_dsm(handle, device_label_dsm_uuid, 0x2,
+ obj = acpi_evaluate_dsm(handle, pci_acpi_dsm_uuid, 0x2,
DEVICE_LABEL_DSM, NULL);
if (!obj)
return -1;
if (!handle)
return false;
- return !!acpi_check_dsm(handle, device_label_dsm_uuid, 0x2,
+ return !!acpi_check_dsm(handle, pci_acpi_dsm_uuid, 0x2,
1 << DEVICE_LABEL_DSM);
}
u8 pos, int cap, int *ttl)
{
u8 id;
+ u16 ent;
+
+ pci_bus_read_config_byte(bus, devfn, pos, &pos);
while ((*ttl)--) {
- pci_bus_read_config_byte(bus, devfn, pos, &pos);
if (pos < 0x40)
break;
pos &= ~3;
- pci_bus_read_config_byte(bus, devfn, pos + PCI_CAP_LIST_ID,
- &id);
+ pci_bus_read_config_word(bus, devfn, pos, &ent);
+
+ id = ent & 0xff;
if (id == 0xff)
break;
if (id == cap)
return pos;
- pos += PCI_CAP_LIST_NEXT;
+ pos = (ent >> 8);
}
return 0;
}
}
#endif
+struct pci_host_bridge *pci_find_host_bridge(struct pci_bus *bus);
+
#endif /* DRIVERS_PCI_H */
}
EXPORT_SYMBOL(pci_disable_link_state);
-void pcie_clear_aspm(struct pci_bus *bus)
-{
- struct pci_dev *child;
-
- if (aspm_force)
- return;
-
- /*
- * Clear any ASPM setup that the firmware has carried out on this bus
- */
- list_for_each_entry(child, &bus->devices, bus_list) {
- __pci_disable_link_state(child, PCIE_LINK_STATE_L0S |
- PCIE_LINK_STATE_L1 |
- PCIE_LINK_STATE_CLKPM,
- false, true);
- }
-}
-
static int pcie_aspm_set_policy(const char *val, struct kernel_param *kp)
{
int i;
|| nhi->subsystem_vendor != 0x2222
|| nhi->subsystem_device != 0x1111)
goto out;
- dev_info(&dev->dev, "quirk: wating for thunderbolt to reestablish pci tunnels...\n");
+ dev_info(&dev->dev, "quirk: waiting for thunderbolt to reestablish PCI tunnels...\n");
device_pm_wait_for_dev(&dev->dev, &nhi->dev);
out:
pci_dev_put(nhi);
static inline void acpiphp_check_host_bridge(struct acpi_device *adev) { }
#endif
+extern const u8 pci_acpi_dsm_uuid[];
+#define DEVICE_LABEL_DSM 0x07
+#define RESET_DELAY_DSM 0x08
+#define FUNCTION_DELAY_DSM 0x09
+
#else /* CONFIG_ACPI */
static inline void acpi_pci_add_bus(struct pci_bus *bus) { }
static inline void acpi_pci_remove_bus(struct pci_bus *bus) { }
void pcie_aspm_powersave_config_link(struct pci_dev *pdev);
void pci_disable_link_state(struct pci_dev *pdev, int state);
void pci_disable_link_state_locked(struct pci_dev *pdev, int state);
-void pcie_clear_aspm(struct pci_bus *bus);
void pcie_no_aspm(void);
#else
static inline void pcie_aspm_init_link_state(struct pci_dev *pdev)
static inline void pci_disable_link_state(struct pci_dev *pdev, int state)
{
}
-static inline void pcie_clear_aspm(struct pci_bus *bus)
-{
-}
static inline void pcie_no_aspm(void)
{
}
struct list_head windows; /* resource_entry */
void (*release_fn)(struct pci_host_bridge *);
void *release_data;
+ unsigned int ignore_reset_delay:1; /* for entire hierarchy */
};
#define to_pci_host_bridge(n) container_of(n, struct pci_host_bridge, dev)