From c6635792737b881021ead417b281067d56ed3380 Mon Sep 17 00:00:00 2001 From: Andy Shevchenko Date: Thu, 30 Aug 2018 13:32:36 +0300 Subject: PCI: Allocate dma_alias_mask with bitmap_zalloc() Switch to bitmap_zalloc() to show clearly what we are allocating. Besides that it returns pointer of bitmap type ("unsigned long *") instead of the opaque "void *". Signed-off-by: Andy Shevchenko Signed-off-by: Bjorn Helgaas --- drivers/pci/pci.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) (limited to 'drivers/pci/pci.c') diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index 1835f3a7aa8d..dc3313d26c79 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -5690,8 +5690,7 @@ int pci_set_vga_state(struct pci_dev *dev, bool decode, void pci_add_dma_alias(struct pci_dev *dev, u8 devfn) { if (!dev->dma_alias_mask) - dev->dma_alias_mask = kcalloc(BITS_TO_LONGS(U8_MAX), - sizeof(long), GFP_KERNEL); + dev->dma_alias_mask = bitmap_zalloc(U8_MAX, GFP_KERNEL); if (!dev->dma_alias_mask) { pci_warn(dev, "Unable to allocate DMA alias mask\n"); return; -- cgit v1.2.3 From 7eb3702504c64425961ee9dd7080396a9477b7e1 Mon Sep 17 00:00:00 2001 From: Randy Dunlap Date: Sun, 2 Sep 2018 19:32:50 -0700 Subject: PCI: Fix pci.c kernel-doc parameter warning Fix kernel-doc warning: ../drivers/pci/pci.c:218: warning: Excess function parameter 'p' description in 'pci_dev_str_match_path' Signed-off-by: Randy Dunlap Signed-off-by: Bjorn Helgaas --- drivers/pci/pci.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/pci/pci.c') diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index dc3313d26c79..455783d3acdf 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -196,7 +196,7 @@ EXPORT_SYMBOL_GPL(pci_ioremap_wc_bar); /** * 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 + * @path: 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 -- cgit v1.2.3 From 81c4b5bf30de01a0f6b43ccaa1d220f4a0a5d99c Mon Sep 17 00:00:00 2001 From: Lukas Wunner Date: Sat, 8 Sep 2018 09:59:01 +0200 Subject: PCI: hotplug: Constify hotplug_slot_ops Hotplug drivers cannot declare their hotplug_slot_ops const, making them attractive targets for attackers, because upon registration of a hotplug slot, __pci_hp_initialize() writes to the "owner" and "mod_name" members in that struct. Fix by moving these members to struct hotplug_slot and constify every driver's hotplug_slot_ops except for pciehp. pciehp constructs its hotplug_slot_ops at runtime based on the PCIe port's capabilities, hence cannot declare them const. It can be converted to __write_rarely once that's mainlined: http://www.openwall.com/lists/kernel-hardening/2016/11/16/3 Signed-off-by: Lukas Wunner Signed-off-by: Bjorn Helgaas Reviewed-by: Rafael J. Wysocki Acked-by: Tyrel Datwyler # drivers/pci/hotplug/rpa* Acked-by: Andy Shevchenko # drivers/platform/x86 Cc: Len Brown Cc: Scott Murray Cc: Benjamin Herrenschmidt Cc: Paul Mackerras Cc: Michael Ellerman Cc: Oliver OHalloran Cc: Gavin Shan Cc: Sebastian Ott Cc: Gerald Schaefer Cc: Corentin Chary Cc: Darren Hart --- drivers/pci/hotplug/acpiphp_core.c | 2 +- drivers/pci/hotplug/cpci_hotplug_core.c | 2 +- drivers/pci/hotplug/cpqphp_core.c | 2 +- drivers/pci/hotplug/ibmphp.h | 2 +- drivers/pci/hotplug/ibmphp_core.c | 2 +- drivers/pci/hotplug/pci_hotplug_core.c | 27 ++++++++++++++------------- drivers/pci/hotplug/pnv_php.c | 2 +- drivers/pci/hotplug/rpaphp.h | 2 +- drivers/pci/hotplug/rpaphp_core.c | 2 +- drivers/pci/hotplug/s390_pci_hpc.c | 2 +- drivers/pci/hotplug/sgi_hotplug.c | 2 +- drivers/pci/hotplug/shpchp_core.c | 2 +- drivers/pci/pci.c | 4 ++-- drivers/pci/slot.c | 2 +- drivers/platform/x86/asus-wmi.c | 3 +-- drivers/platform/x86/eeepc-laptop.c | 3 +-- include/linux/pci_hotplug.h | 10 +++++----- 17 files changed, 35 insertions(+), 36 deletions(-) (limited to 'drivers/pci/pci.c') diff --git a/drivers/pci/hotplug/acpiphp_core.c b/drivers/pci/hotplug/acpiphp_core.c index ad32ffbc4b91..e883cef0f3bc 100644 --- a/drivers/pci/hotplug/acpiphp_core.c +++ b/drivers/pci/hotplug/acpiphp_core.c @@ -57,7 +57,7 @@ static int get_attention_status(struct hotplug_slot *slot, u8 *value); static int get_latch_status(struct hotplug_slot *slot, u8 *value); static int get_adapter_status(struct hotplug_slot *slot, u8 *value); -static struct hotplug_slot_ops acpi_hotplug_slot_ops = { +static const struct hotplug_slot_ops acpi_hotplug_slot_ops = { .enable_slot = enable_slot, .disable_slot = disable_slot, .set_attention_status = set_attention_status, diff --git a/drivers/pci/hotplug/cpci_hotplug_core.c b/drivers/pci/hotplug/cpci_hotplug_core.c index 52a339baf06c..97c32e4c74c8 100644 --- a/drivers/pci/hotplug/cpci_hotplug_core.c +++ b/drivers/pci/hotplug/cpci_hotplug_core.c @@ -57,7 +57,7 @@ static int get_attention_status(struct hotplug_slot *slot, u8 *value); static int get_adapter_status(struct hotplug_slot *slot, u8 *value); static int get_latch_status(struct hotplug_slot *slot, u8 *value); -static struct hotplug_slot_ops cpci_hotplug_slot_ops = { +static const struct hotplug_slot_ops cpci_hotplug_slot_ops = { .enable_slot = enable_slot, .disable_slot = disable_slot, .set_attention_status = set_attention_status, diff --git a/drivers/pci/hotplug/cpqphp_core.c b/drivers/pci/hotplug/cpqphp_core.c index 5a06636e910a..3409b62fceac 100644 --- a/drivers/pci/hotplug/cpqphp_core.c +++ b/drivers/pci/hotplug/cpqphp_core.c @@ -560,7 +560,7 @@ static int get_adapter_status(struct hotplug_slot *hotplug_slot, u8 *value) return 0; } -static struct hotplug_slot_ops cpqphp_hotplug_slot_ops = { +static const struct hotplug_slot_ops cpqphp_hotplug_slot_ops = { .set_attention_status = set_attention_status, .enable_slot = process_SI, .disable_slot = process_SS, diff --git a/drivers/pci/hotplug/ibmphp.h b/drivers/pci/hotplug/ibmphp.h index fddb78606c74..db387e10581e 100644 --- a/drivers/pci/hotplug/ibmphp.h +++ b/drivers/pci/hotplug/ibmphp.h @@ -740,7 +740,7 @@ int ibmphp_do_disable_slot(struct slot *slot_cur); int ibmphp_update_slot_info(struct slot *); /* This function is called from HPC, so we need it to not be be static */ int ibmphp_configure_card(struct pci_func *, u8); int ibmphp_unconfigure_card(struct slot **, int); -extern struct hotplug_slot_ops ibmphp_hotplug_slot_ops; +extern const struct hotplug_slot_ops ibmphp_hotplug_slot_ops; #endif //__IBMPHP_H diff --git a/drivers/pci/hotplug/ibmphp_core.c b/drivers/pci/hotplug/ibmphp_core.c index 4ea57e9019f1..b82fdc17040d 100644 --- a/drivers/pci/hotplug/ibmphp_core.c +++ b/drivers/pci/hotplug/ibmphp_core.c @@ -1259,7 +1259,7 @@ error: goto exit; } -struct hotplug_slot_ops ibmphp_hotplug_slot_ops = { +const struct hotplug_slot_ops ibmphp_hotplug_slot_ops = { .set_attention_status = set_attention_status, .enable_slot = enable_slot, .disable_slot = ibmphp_disable_slot, diff --git a/drivers/pci/hotplug/pci_hotplug_core.c b/drivers/pci/hotplug/pci_hotplug_core.c index 90fde5f106d8..ede2ed6f4ce0 100644 --- a/drivers/pci/hotplug/pci_hotplug_core.c +++ b/drivers/pci/hotplug/pci_hotplug_core.c @@ -49,15 +49,15 @@ static DEFINE_MUTEX(pci_hp_mutex); #define GET_STATUS(name, type) \ static int get_##name(struct hotplug_slot *slot, type *value) \ { \ - struct hotplug_slot_ops *ops = slot->ops; \ + const struct hotplug_slot_ops *ops = slot->ops; \ int retval = 0; \ - if (!try_module_get(ops->owner)) \ + if (!try_module_get(slot->owner)) \ return -ENODEV; \ if (ops->get_##name) \ retval = ops->get_##name(slot, value); \ else \ *value = slot->info->name; \ - module_put(ops->owner); \ + module_put(slot->owner); \ return retval; \ } @@ -90,7 +90,7 @@ static ssize_t power_write_file(struct pci_slot *pci_slot, const char *buf, power = (u8)(lpower & 0xff); dbg("power = %d\n", power); - if (!try_module_get(slot->ops->owner)) { + if (!try_module_get(slot->owner)) { retval = -ENODEV; goto exit; } @@ -109,7 +109,7 @@ static ssize_t power_write_file(struct pci_slot *pci_slot, const char *buf, err("Illegal value specified for power\n"); retval = -EINVAL; } - module_put(slot->ops->owner); + module_put(slot->owner); exit: if (retval) @@ -138,7 +138,8 @@ static ssize_t attention_read_file(struct pci_slot *pci_slot, char *buf) static ssize_t attention_write_file(struct pci_slot *pci_slot, const char *buf, size_t count) { - struct hotplug_slot_ops *ops = pci_slot->hotplug->ops; + struct hotplug_slot *slot = pci_slot->hotplug; + const struct hotplug_slot_ops *ops = slot->ops; unsigned long lattention; u8 attention; int retval = 0; @@ -147,13 +148,13 @@ static ssize_t attention_write_file(struct pci_slot *pci_slot, const char *buf, attention = (u8)(lattention & 0xff); dbg(" - attention = %d\n", attention); - if (!try_module_get(ops->owner)) { + if (!try_module_get(slot->owner)) { retval = -ENODEV; goto exit; } if (ops->set_attention_status) - retval = ops->set_attention_status(pci_slot->hotplug, attention); - module_put(ops->owner); + retval = ops->set_attention_status(slot, attention); + module_put(slot->owner); exit: if (retval) @@ -213,13 +214,13 @@ static ssize_t test_write_file(struct pci_slot *pci_slot, const char *buf, test = (u32)(ltest & 0xffffffff); dbg("test = %d\n", test); - if (!try_module_get(slot->ops->owner)) { + if (!try_module_get(slot->owner)) { retval = -ENODEV; goto exit; } if (slot->ops->hardware_test) retval = slot->ops->hardware_test(slot, test); - module_put(slot->ops->owner); + module_put(slot->owner); exit: if (retval) @@ -447,8 +448,8 @@ int __pci_hp_initialize(struct hotplug_slot *slot, struct pci_bus *bus, if ((slot->info == NULL) || (slot->ops == NULL)) return -EINVAL; - slot->ops->owner = owner; - slot->ops->mod_name = mod_name; + slot->owner = owner; + slot->mod_name = mod_name; /* * No problems if we call this interface from both ACPI_PCI_SLOT diff --git a/drivers/pci/hotplug/pnv_php.c b/drivers/pci/hotplug/pnv_php.c index 3276a5e4c430..12b92a0ff688 100644 --- a/drivers/pci/hotplug/pnv_php.c +++ b/drivers/pci/hotplug/pnv_php.c @@ -530,7 +530,7 @@ static int pnv_php_disable_slot(struct hotplug_slot *slot) return ret; } -static struct hotplug_slot_ops php_slot_ops = { +static const struct hotplug_slot_ops php_slot_ops = { .get_power_status = pnv_php_get_power_state, .get_adapter_status = pnv_php_get_adapter_state, .set_attention_status = pnv_php_set_attention_state, diff --git a/drivers/pci/hotplug/rpaphp.h b/drivers/pci/hotplug/rpaphp.h index c8311724bd76..f83347819f7b 100644 --- a/drivers/pci/hotplug/rpaphp.h +++ b/drivers/pci/hotplug/rpaphp.h @@ -70,7 +70,7 @@ struct slot { struct hotplug_slot *hotplug_slot; }; -extern struct hotplug_slot_ops rpaphp_hotplug_slot_ops; +extern const struct hotplug_slot_ops rpaphp_hotplug_slot_ops; extern struct list_head rpaphp_slot_head; /* function prototypes */ diff --git a/drivers/pci/hotplug/rpaphp_core.c b/drivers/pci/hotplug/rpaphp_core.c index 857c358b727b..8620a3f8c987 100644 --- a/drivers/pci/hotplug/rpaphp_core.c +++ b/drivers/pci/hotplug/rpaphp_core.c @@ -477,7 +477,7 @@ static int disable_slot(struct hotplug_slot *hotplug_slot) return 0; } -struct hotplug_slot_ops rpaphp_hotplug_slot_ops = { +const struct hotplug_slot_ops rpaphp_hotplug_slot_ops = { .enable_slot = enable_slot, .disable_slot = disable_slot, .set_attention_status = set_attention_status, diff --git a/drivers/pci/hotplug/s390_pci_hpc.c b/drivers/pci/hotplug/s390_pci_hpc.c index 93b5341d282c..5bd45fd4a92a 100644 --- a/drivers/pci/hotplug/s390_pci_hpc.c +++ b/drivers/pci/hotplug/s390_pci_hpc.c @@ -130,7 +130,7 @@ static int get_adapter_status(struct hotplug_slot *hotplug_slot, u8 *value) return 0; } -static struct hotplug_slot_ops s390_hotplug_slot_ops = { +static const struct hotplug_slot_ops s390_hotplug_slot_ops = { .enable_slot = enable_slot, .disable_slot = disable_slot, .get_power_status = get_power_status, diff --git a/drivers/pci/hotplug/sgi_hotplug.c b/drivers/pci/hotplug/sgi_hotplug.c index babd23409f61..af4c28c574dd 100644 --- a/drivers/pci/hotplug/sgi_hotplug.c +++ b/drivers/pci/hotplug/sgi_hotplug.c @@ -80,7 +80,7 @@ static int enable_slot(struct hotplug_slot *slot); static int disable_slot(struct hotplug_slot *slot); static inline int get_power_status(struct hotplug_slot *slot, u8 *value); -static struct hotplug_slot_ops sn_hotplug_slot_ops = { +static const struct hotplug_slot_ops sn_hotplug_slot_ops = { .enable_slot = enable_slot, .disable_slot = disable_slot, .get_power_status = get_power_status, diff --git a/drivers/pci/hotplug/shpchp_core.c b/drivers/pci/hotplug/shpchp_core.c index 97cee23f3d51..26cbea04237c 100644 --- a/drivers/pci/hotplug/shpchp_core.c +++ b/drivers/pci/hotplug/shpchp_core.c @@ -51,7 +51,7 @@ static int get_attention_status(struct hotplug_slot *slot, u8 *value); static int get_latch_status(struct hotplug_slot *slot, u8 *value); static int get_adapter_status(struct hotplug_slot *slot, u8 *value); -static struct hotplug_slot_ops shpchp_hotplug_slot_ops = { +static const struct hotplug_slot_ops shpchp_hotplug_slot_ops = { .set_attention_status = set_attention_status, .enable_slot = enable_slot, .disable_slot = disable_slot, diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index 1835f3a7aa8d..0e54588825cb 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -4571,13 +4571,13 @@ static int pci_reset_hotplug_slot(struct hotplug_slot *hotplug, int probe) { int rc = -ENOTTY; - if (!hotplug || !try_module_get(hotplug->ops->owner)) + if (!hotplug || !try_module_get(hotplug->owner)) return rc; if (hotplug->ops->reset_slot) rc = hotplug->ops->reset_slot(hotplug, probe); - module_put(hotplug->ops->owner); + module_put(hotplug->owner); return rc; } diff --git a/drivers/pci/slot.c b/drivers/pci/slot.c index e634229ece89..145cd953b518 100644 --- a/drivers/pci/slot.c +++ b/drivers/pci/slot.c @@ -371,7 +371,7 @@ void pci_hp_create_module_link(struct pci_slot *pci_slot) if (!slot || !slot->ops) return; - kobj = kset_find_obj(module_kset, slot->ops->mod_name); + kobj = kset_find_obj(module_kset, slot->mod_name); if (!kobj) return; ret = sysfs_create_link(&pci_slot->kobj, kobj, "module"); diff --git a/drivers/platform/x86/asus-wmi.c b/drivers/platform/x86/asus-wmi.c index 2d6e272315a8..a8aa2eadfd82 100644 --- a/drivers/platform/x86/asus-wmi.c +++ b/drivers/platform/x86/asus-wmi.c @@ -868,8 +868,7 @@ static int asus_get_adapter_status(struct hotplug_slot *hotplug_slot, return 0; } -static struct hotplug_slot_ops asus_hotplug_slot_ops = { - .owner = THIS_MODULE, +static const struct hotplug_slot_ops asus_hotplug_slot_ops = { .get_adapter_status = asus_get_adapter_status, .get_power_status = asus_get_adapter_status, }; diff --git a/drivers/platform/x86/eeepc-laptop.c b/drivers/platform/x86/eeepc-laptop.c index a4bbf6ecd1f0..41a364376e91 100644 --- a/drivers/platform/x86/eeepc-laptop.c +++ b/drivers/platform/x86/eeepc-laptop.c @@ -726,8 +726,7 @@ static int eeepc_get_adapter_status(struct hotplug_slot *hotplug_slot, return 0; } -static struct hotplug_slot_ops eeepc_hotplug_slot_ops = { - .owner = THIS_MODULE, +static const struct hotplug_slot_ops eeepc_hotplug_slot_ops = { .get_adapter_status = eeepc_get_adapter_status, .get_power_status = eeepc_get_adapter_status, }; diff --git a/include/linux/pci_hotplug.h b/include/linux/pci_hotplug.h index a6d6650a0490..372dbe95c207 100644 --- a/include/linux/pci_hotplug.h +++ b/include/linux/pci_hotplug.h @@ -16,8 +16,6 @@ /** * struct hotplug_slot_ops -the callbacks that the hotplug pci core can use - * @owner: The module owner of this structure - * @mod_name: The module name (KBUILD_MODNAME) of this structure * @enable_slot: Called when the user wants to enable a specific pci slot * @disable_slot: Called when the user wants to disable a specific pci slot * @set_attention_status: Called to set the specific slot's attention LED to @@ -46,8 +44,6 @@ * set an LED, enable / disable power, etc.) */ struct hotplug_slot_ops { - struct module *owner; - const char *mod_name; int (*enable_slot) (struct hotplug_slot *slot); int (*disable_slot) (struct hotplug_slot *slot); int (*set_attention_status) (struct hotplug_slot *slot, u8 value); @@ -82,15 +78,19 @@ struct hotplug_slot_info { * this slot. * @private: used by the hotplug pci controller driver to store whatever it * needs. + * @owner: The module owner of this structure + * @mod_name: The module name (KBUILD_MODNAME) of this structure */ struct hotplug_slot { - struct hotplug_slot_ops *ops; + const struct hotplug_slot_ops *ops; struct hotplug_slot_info *info; void *private; /* Variables below this are for use only by the hotplug pci core. */ struct list_head slot_list; struct pci_slot *pci_slot; + struct module *owner; + const char *mod_name; }; static inline const char *hotplug_slot_name(const struct hotplug_slot *slot) -- cgit v1.2.3 From 4f802170a861265680cad03f47b19c4c3a137052 Mon Sep 17 00:00:00 2001 From: Keith Busch Date: Thu, 20 Sep 2018 10:27:08 -0600 Subject: PCI/DPC: Save and restore config state This patch provides DPC save and restore capabilities. This is necessary for the driver to observe DPC events in the event the configuration space needs to be restored after a reset. Signed-off-by: Keith Busch Signed-off-by: Bjorn Helgaas Reviewed-by: Sinan Kaya --- drivers/pci/pci.c | 2 ++ drivers/pci/pci.h | 8 +++++++ drivers/pci/pcie/dpc.c | 61 +++++++++++++++++++++++++++++++++++++++++++++----- 3 files changed, 65 insertions(+), 6 deletions(-) (limited to 'drivers/pci/pci.c') diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index 0e54588825cb..d6bb56fbee6d 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -1284,6 +1284,7 @@ int pci_save_state(struct pci_dev *dev) if (i != 0) return i; + pci_save_dpc_state(dev); return pci_save_vc_state(dev); } EXPORT_SYMBOL(pci_save_state); @@ -1378,6 +1379,7 @@ void pci_restore_state(struct pci_dev *dev) pci_restore_ats_state(dev); pci_restore_vc_state(dev); pci_restore_rebar_state(dev); + pci_restore_dpc_state(dev); pci_cleanup_aer_error_status_regs(dev); diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h index 6e0d1528d471..b5af5642c6c9 100644 --- a/drivers/pci/pci.h +++ b/drivers/pci/pci.h @@ -346,6 +346,14 @@ int aer_get_device_error_info(struct pci_dev *dev, struct aer_err_info *info); void aer_print_error(struct pci_dev *dev, struct aer_err_info *info); #endif /* CONFIG_PCIEAER */ +#ifdef CONFIG_PCIE_DPC +void pci_save_dpc_state(struct pci_dev *dev); +void pci_restore_dpc_state(struct pci_dev *dev); +#else +static inline void pci_save_dpc_state(struct pci_dev *dev) {} +static inline void pci_restore_dpc_state(struct pci_dev *dev) {} +#endif + #ifdef CONFIG_PCI_ATS void pci_restore_ats_state(struct pci_dev *dev); #else diff --git a/drivers/pci/pcie/dpc.c b/drivers/pci/pcie/dpc.c index a1fd16bf1cab..ed815a28512e 100644 --- a/drivers/pci/pcie/dpc.c +++ b/drivers/pci/pcie/dpc.c @@ -44,6 +44,58 @@ static const char * const rp_pio_error_string[] = { "Memory Request Completion Timeout", /* Bit Position 18 */ }; +static struct dpc_dev *to_dpc_dev(struct pci_dev *dev) +{ + struct device *device; + + device = pcie_port_find_device(dev, PCIE_PORT_SERVICE_DPC); + if (!device) + return NULL; + return get_service_data(to_pcie_device(device)); +} + +void pci_save_dpc_state(struct pci_dev *dev) +{ + struct dpc_dev *dpc; + struct pci_cap_saved_state *save_state; + u16 *cap; + + if (!pci_is_pcie(dev)) + return; + + dpc = to_dpc_dev(dev); + if (!dpc) + return; + + save_state = pci_find_saved_ext_cap(dev, PCI_EXT_CAP_ID_DPC); + if (!save_state) + return; + + cap = (u16 *)&save_state->cap.data[0]; + pci_read_config_word(dev, dpc->cap_pos + PCI_EXP_DPC_CTL, cap); +} + +void pci_restore_dpc_state(struct pci_dev *dev) +{ + struct dpc_dev *dpc; + struct pci_cap_saved_state *save_state; + u16 *cap; + + if (!pci_is_pcie(dev)) + return; + + dpc = to_dpc_dev(dev); + if (!dpc) + return; + + save_state = pci_find_saved_ext_cap(dev, PCI_EXT_CAP_ID_DPC); + if (!save_state) + return; + + cap = (u16 *)&save_state->cap.data[0]; + pci_write_config_word(dev, dpc->cap_pos + PCI_EXP_DPC_CTL, *cap); +} + static int dpc_wait_rp_inactive(struct dpc_dev *dpc) { unsigned long timeout = jiffies + HZ; @@ -67,18 +119,13 @@ static int dpc_wait_rp_inactive(struct dpc_dev *dpc) static pci_ers_result_t dpc_reset_link(struct pci_dev *pdev) { struct dpc_dev *dpc; - struct pcie_device *pciedev; - struct device *devdpc; - u16 cap; /* * DPC disables the Link automatically in hardware, so it has * already been reset by the time we get here. */ - devdpc = pcie_port_find_device(pdev, PCIE_PORT_SERVICE_DPC); - pciedev = to_pcie_device(devdpc); - dpc = get_service_data(pciedev); + dpc = to_dpc_dev(pdev); cap = dpc->cap_pos; /* @@ -259,6 +306,8 @@ static int dpc_probe(struct pcie_device *dev) FLAG(cap, PCI_EXP_DPC_CAP_POISONED_TLP), FLAG(cap, PCI_EXP_DPC_CAP_SW_TRIGGER), dpc->rp_log_size, FLAG(cap, PCI_EXP_DPC_CAP_DL_ACTIVE)); + + pci_add_ext_cap_save_buffer(pdev, PCI_EXT_CAP_ID_DPC, sizeof(u16)); return status; } -- cgit v1.2.3 From c4eed62a214330908eec11b0dc170d34fa50b412 Mon Sep 17 00:00:00 2001 From: Keith Busch Date: Thu, 20 Sep 2018 10:27:11 -0600 Subject: PCI/ERR: Use slot reset if available The secondary bus reset may have link side effects that a hotplug capable port may incorrectly react to. Use the slot specific reset for hotplug ports, fixing the undesirable link down-up handling during error recovering. Signed-off-by: Keith Busch [bhelgaas: fold in https://lore.kernel.org/linux-pci/20180926152326.14821-1-keith.busch@intel.com for issue reported by Stephen Rothwell ] Signed-off-by: Bjorn Helgaas Reviewed-by: Sinan Kaya --- drivers/pci/pci.c | 37 +++++++++++++++++++++++++++++++++++++ drivers/pci/pci.h | 2 ++ drivers/pci/pcie/aer.c | 2 +- drivers/pci/pcie/err.c | 2 +- drivers/pci/slot.c | 1 - 5 files changed, 41 insertions(+), 3 deletions(-) (limited to 'drivers/pci/pci.c') diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index d6bb56fbee6d..6916af269b19 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -35,6 +35,8 @@ #include #include "pci.h" +DEFINE_MUTEX(pci_slot_mutex); + const char *pci_power_names[] = { "error", "D0", "D1", "D2", "D3hot", "D3cold", "unknown", }; @@ -5155,6 +5157,41 @@ static int pci_bus_reset(struct pci_bus *bus, int probe) return ret; } +/** + * pci_bus_error_reset - reset the bridge's subordinate bus + * @bridge: The parent device that connects to the bus to reset + * + * This function will first try to reset the slots on this bus if the method is + * available. If slot reset fails or is not available, this will fall back to a + * secondary bus reset. + */ +int pci_bus_error_reset(struct pci_dev *bridge) +{ + struct pci_bus *bus = bridge->subordinate; + struct pci_slot *slot; + + if (!bus) + return -ENOTTY; + + mutex_lock(&pci_slot_mutex); + if (list_empty(&bus->slots)) + goto bus_reset; + + list_for_each_entry(slot, &bus->slots, list) + if (pci_probe_reset_slot(slot)) + goto bus_reset; + + list_for_each_entry(slot, &bus->slots, list) + if (pci_slot_reset(slot, 0)) + goto bus_reset; + + mutex_unlock(&pci_slot_mutex); + return 0; +bus_reset: + mutex_unlock(&pci_slot_mutex); + return pci_bus_reset(bridge->subordinate, 0); +} + /** * pci_probe_reset_bus - probe whether a PCI bus can be reset * @bus: PCI bus to probe diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h index b5af5642c6c9..b4ada8c383a8 100644 --- a/drivers/pci/pci.h +++ b/drivers/pci/pci.h @@ -35,6 +35,7 @@ int pci_mmap_fits(struct pci_dev *pdev, int resno, struct vm_area_struct *vmai, int pci_probe_reset_function(struct pci_dev *dev); int pci_bridge_secondary_bus_reset(struct pci_dev *dev); +int pci_bus_error_reset(struct pci_dev *dev); /** * struct pci_platform_pm_ops - Firmware PM callbacks @@ -136,6 +137,7 @@ static inline void pci_remove_legacy_files(struct pci_bus *bus) { return; } /* Lock for read/write access to pci device and bus lists */ extern struct rw_semaphore pci_bus_sem; +extern struct mutex pci_slot_mutex; extern raw_spinlock_t pci_lock; diff --git a/drivers/pci/pcie/aer.c b/drivers/pci/pcie/aer.c index 5c3ea7254c6a..1563e22600ec 100644 --- a/drivers/pci/pcie/aer.c +++ b/drivers/pci/pcie/aer.c @@ -1528,7 +1528,7 @@ static pci_ers_result_t aer_root_reset(struct pci_dev *dev) reg32 &= ~ROOT_PORT_INTR_ON_MESG_MASK; pci_write_config_dword(dev, pos + PCI_ERR_ROOT_COMMAND, reg32); - rc = pci_bridge_secondary_bus_reset(dev); + rc = pci_bus_error_reset(dev); pci_printk(KERN_DEBUG, dev, "Root Port link has been reset\n"); /* Clear Root Error Status */ diff --git a/drivers/pci/pcie/err.c b/drivers/pci/pcie/err.c index cac406b6e936..62ab665f0f03 100644 --- a/drivers/pci/pcie/err.c +++ b/drivers/pci/pcie/err.c @@ -177,7 +177,7 @@ static pci_ers_result_t default_reset_link(struct pci_dev *dev) { int rc; - rc = pci_bridge_secondary_bus_reset(dev); + rc = pci_bus_error_reset(dev); pci_printk(KERN_DEBUG, dev, "downstream link has been reset\n"); return rc ? PCI_ERS_RESULT_DISCONNECT : PCI_ERS_RESULT_RECOVERED; } diff --git a/drivers/pci/slot.c b/drivers/pci/slot.c index 145cd953b518..c46d5e1ff536 100644 --- a/drivers/pci/slot.c +++ b/drivers/pci/slot.c @@ -14,7 +14,6 @@ struct kset *pci_slots_kset; EXPORT_SYMBOL_GPL(pci_slots_kset); -static DEFINE_MUTEX(pci_slot_mutex); static ssize_t pci_slot_attr_show(struct kobject *kobj, struct attribute *attr, char *buf) -- cgit v1.2.3 From d6112f8def514e019658bcc9b57d53acdb71ca3f Mon Sep 17 00:00:00 2001 From: Felipe Balbi Date: Fri, 7 Sep 2018 09:16:51 +0300 Subject: PCI: Add support for Immediate Readiness MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit PCIe r4.0, sec 7.5.1.1.4 defines a new bit in the Status Register: Immediate Readiness – This optional bit, when Set, indicates the Function is guaranteed to be ready to successfully complete valid configuration accesses at any time following any reset that the host is capable of issuing Configuration Requests to this Function. When this bit is Set, for accesses to this Function, software is exempt from all requirements to delay configuration accesses following any type of reset, including but not limited to the timing requirements defined in Section 6.6. This means that all delays after a Conventional or Function Reset can be skipped. This patch reads such bit and caches its value in a flag inside struct pci_dev to be checked later if we should delay or can skip delays after a reset. While at that, also move the explicit msleep(100) call from pcie_flr() and pci_af_flr() to pci_dev_wait(). Signed-off-by: Felipe Balbi [bhelgaas: rename PCI_STATUS_IMMEDIATE to PCI_STATUS_IMM_READY] Signed-off-by: Bjorn Helgaas --- drivers/pci/pci.c | 13 ++++++++++++- include/linux/pci.h | 1 + include/uapi/linux/pci_regs.h | 1 + 3 files changed, 14 insertions(+), 1 deletion(-) (limited to 'drivers/pci/pci.c') diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index 1835f3a7aa8d..ee7c2f4eef9b 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -999,7 +999,7 @@ static void __pci_start_power_transition(struct pci_dev *dev, pci_power_t state) * because have already delayed for the bridge. */ if (dev->runtime_d3cold) { - if (dev->d3cold_delay) + if (dev->d3cold_delay && !dev->imm_ready) msleep(dev->d3cold_delay); /* * When powering on a bridge from D3cold, the @@ -2644,6 +2644,7 @@ EXPORT_SYMBOL_GPL(pci_d3cold_disable); void pci_pm_init(struct pci_dev *dev) { int pm; + u16 status; u16 pmc; pm_runtime_forbid(&dev->dev); @@ -2706,6 +2707,10 @@ void pci_pm_init(struct pci_dev *dev) /* Disable the PME# generation functionality */ pci_pme_active(dev, false); } + + pci_read_config_word(dev, PCI_STATUS, &status); + if (status & PCI_STATUS_IMM_READY) + dev->imm_ready = 1; } static unsigned long pci_ea_flags(struct pci_dev *dev, u8 prop) @@ -4376,6 +4381,9 @@ int pcie_flr(struct pci_dev *dev) pcie_capability_set_word(dev, PCI_EXP_DEVCTL, PCI_EXP_DEVCTL_BCR_FLR); + if (dev->imm_ready) + return 0; + /* * Per PCIe r4.0, sec 6.6.2, a device must complete an FLR within * 100ms, but may silently discard requests while the FLR is in @@ -4417,6 +4425,9 @@ static int pci_af_flr(struct pci_dev *dev, int probe) pci_write_config_byte(dev, pos + PCI_AF_CTRL, PCI_AF_CTRL_FLR); + if (dev->imm_ready) + return 0; + /* * Per Advanced Capabilities for Conventional PCI ECN, 13 April 2006, * updated 27 July 2006; a device must complete an FLR within diff --git a/include/linux/pci.h b/include/linux/pci.h index 6925828f9f25..60da5d7d4310 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -325,6 +325,7 @@ struct pci_dev { pci_power_t current_state; /* Current operating state. In ACPI, this is D0-D3, D0 being fully functional, and D3 being off. */ + unsigned int imm_ready:1; /* Supports Immediate Readiness */ u8 pm_cap; /* PM capability offset */ unsigned int pme_support:5; /* Bitmask of states from which PME# can be generated */ diff --git a/include/uapi/linux/pci_regs.h b/include/uapi/linux/pci_regs.h index ee556ccc93f4..e1e9888c85e6 100644 --- a/include/uapi/linux/pci_regs.h +++ b/include/uapi/linux/pci_regs.h @@ -52,6 +52,7 @@ #define PCI_COMMAND_INTX_DISABLE 0x400 /* INTx Emulation Disable */ #define PCI_STATUS 0x06 /* 16 bits */ +#define PCI_STATUS_IMM_READY 0x01 /* Immediate Readiness */ #define PCI_STATUS_INTERRUPT 0x08 /* Interrupt status */ #define PCI_STATUS_CAP_LIST 0x10 /* Support Capability List */ #define PCI_STATUS_66MHZ 0x20 /* Support 66 MHz PCI 2.1 bus */ -- cgit v1.2.3 From f0157160b359b1d263ee9d4e0a435a7ad85bbcea Mon Sep 17 00:00:00 2001 From: Keith Busch Date: Thu, 20 Sep 2018 10:27:17 -0600 Subject: PCI: Make link active reporting detection generic The spec has timing requirements when waiting for a link to become active after a conventional reset. Implement those hard delays when waiting for an active link so pciehp and dpc drivers don't need to duplicate this. For devices that don't support data link layer active reporting, wait the fixed time recommended by the PCIe spec. Signed-off-by: Keith Busch [bhelgaas: changelog] Signed-off-by: Bjorn Helgaas Reviewed-by: Sinan Kaya --- drivers/pci/hotplug/pciehp.h | 6 ------ drivers/pci/hotplug/pciehp_hpc.c | 22 ++-------------------- drivers/pci/pci.c | 33 +++++++++++++++++++++++++++------ drivers/pci/pcie/dpc.c | 4 +++- drivers/pci/probe.c | 1 + include/linux/pci.h | 1 + 6 files changed, 34 insertions(+), 33 deletions(-) (limited to 'drivers/pci/pci.c') diff --git a/drivers/pci/hotplug/pciehp.h b/drivers/pci/hotplug/pciehp.h index 3740f1a759c5..75fd52571107 100644 --- a/drivers/pci/hotplug/pciehp.h +++ b/drivers/pci/hotplug/pciehp.h @@ -62,11 +62,6 @@ do { \ * struct controller - PCIe hotplug controller * @pcie: pointer to the controller's PCIe port service device * @slot_cap: cached copy of the Slot Capabilities register - * @link_active_reporting: cached copy of Data Link Layer Link Active Reporting - * Capable bit in Link Capabilities register; if this bit is zero, the - * Data Link Layer Link Active bit in the Link Status register will never - * be set and the driver is thus confined to wait 1 second before assuming - * the link to a hotplugged device is up and accessing it * @slot_ctrl: cached copy of the Slot Control register * @ctrl_lock: serializes writes to the Slot Control register * @cmd_started: jiffies when the Slot Control register was last written; @@ -103,7 +98,6 @@ struct controller { struct pcie_device *pcie; u32 slot_cap; /* capabilities and quirks */ - unsigned int link_active_reporting:1; u16 slot_ctrl; /* control register access */ struct mutex ctrl_lock; diff --git a/drivers/pci/hotplug/pciehp_hpc.c b/drivers/pci/hotplug/pciehp_hpc.c index 7b5f9db60d9a..f0f3f4a3dac4 100644 --- a/drivers/pci/hotplug/pciehp_hpc.c +++ b/drivers/pci/hotplug/pciehp_hpc.c @@ -214,13 +214,6 @@ bool pciehp_check_link_active(struct controller *ctrl) return ret; } -static void pcie_wait_link_active(struct controller *ctrl) -{ - struct pci_dev *pdev = ctrl_dev(ctrl); - - pcie_wait_for_link(pdev, true); -} - static bool pci_bus_check_dev(struct pci_bus *bus, int devfn) { u32 l; @@ -253,18 +246,9 @@ int pciehp_check_link_status(struct controller *ctrl) bool found; u16 lnk_status; - /* - * Data Link Layer Link Active Reporting must be capable for - * hot-plug capable downstream port. But old controller might - * not implement it. In this case, we wait for 1000 ms. - */ - if (ctrl->link_active_reporting) - pcie_wait_link_active(ctrl); - else - msleep(1000); + if (!pcie_wait_for_link(pdev, true)) + return -1; - /* wait 100ms before read pci conf, and try in 1s */ - msleep(100); found = pci_bus_check_dev(ctrl->pcie->port->subordinate, PCI_DEVFN(0, 0)); @@ -865,8 +849,6 @@ struct controller *pcie_init(struct pcie_device *dev) /* Check if Data Link Layer Link Active Reporting is implemented */ pcie_capability_read_dword(pdev, PCI_EXP_LNKCAP, &link_cap); - if (link_cap & PCI_EXP_LNKCAP_DLLLARC) - ctrl->link_active_reporting = 1; /* Clear all remaining event bits in Slot Status register. */ pcie_capability_write_word(pdev, PCI_EXP_SLTSTA, diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index 6916af269b19..4b0b1d0548f0 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -4489,21 +4489,42 @@ bool pcie_wait_for_link(struct pci_dev *pdev, bool active) bool ret; u16 lnk_status; + /* + * Some controllers might not implement link active reporting. In this + * case, we wait for 1000 + 100 ms. + */ + if (!pdev->link_active_reporting) { + msleep(1100); + return true; + } + + /* + * PCIe r4.0 sec 6.6.1, a component must enter LTSSM Detect within 20ms, + * after which we should expect an link active if the reset was + * successful. If so, software must wait a minimum 100ms before sending + * configuration requests to devices downstream this port. + * + * If the link fails to activate, either the device was physically + * removed or the link is permanently failed. + */ + if (active) + msleep(20); for (;;) { pcie_capability_read_word(pdev, PCI_EXP_LNKSTA, &lnk_status); ret = !!(lnk_status & PCI_EXP_LNKSTA_DLLLA); if (ret == active) - return true; + break; if (timeout <= 0) break; msleep(10); timeout -= 10; } - - pci_info(pdev, "Data Link Layer Link Active not %s in 1000 msec\n", - active ? "set" : "cleared"); - - return false; + if (active && ret) + msleep(100); + else if (ret != active) + pci_info(pdev, "Data Link Layer Link Active not %s in 1000 msec\n", + active ? "set" : "cleared"); + return ret == active; } void pci_reset_secondary_bus(struct pci_dev *dev) diff --git a/drivers/pci/pcie/dpc.c b/drivers/pci/pcie/dpc.c index 23e063aefddf..e435d12e61a0 100644 --- a/drivers/pci/pcie/dpc.c +++ b/drivers/pci/pcie/dpc.c @@ -140,10 +140,12 @@ static pci_ers_result_t dpc_reset_link(struct pci_dev *pdev) pci_write_config_word(pdev, cap + PCI_EXP_DPC_STATUS, PCI_EXP_DPC_STATUS_TRIGGER); + if (!pcie_wait_for_link(pdev, true)) + return PCI_ERS_RESULT_DISCONNECT; + return PCI_ERS_RESULT_RECOVERED; } - static void dpc_process_rp_pio_error(struct dpc_dev *dpc) { struct device *dev = &dpc->dev->device; diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c index 201f9e5ff55c..bb2999d1b199 100644 --- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -713,6 +713,7 @@ static void pci_set_bus_speed(struct pci_bus *bus) pcie_capability_read_dword(bridge, PCI_EXP_LNKCAP, &linkcap); bus->max_bus_speed = pcie_link_speed[linkcap & PCI_EXP_LNKCAP_SLS]; + bridge->link_active_reporting = !!(linkcap & PCI_EXP_LNKCAP_DLLLARC); pcie_capability_read_word(bridge, PCI_EXP_LNKSTA, &linksta); pcie_update_link_speed(bus, linksta); diff --git a/include/linux/pci.h b/include/linux/pci.h index 6925828f9f25..896b42032ec5 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -402,6 +402,7 @@ struct pci_dev { unsigned int has_secondary_link:1; unsigned int non_compliant_bars:1; /* Broken BARs; ignore them */ unsigned int is_probed:1; /* Device probing in progress */ + unsigned int link_active_reporting:1;/* Device capable of reporting link active */ pci_dev_flags_t dev_flags; atomic_t enable_cnt; /* pci_enable_device has been called */ -- cgit v1.2.3 From ac86e8eeb0542d1089d8cba55884eeeb9410f027 Mon Sep 17 00:00:00 2001 From: Mika Westerberg Date: Thu, 27 Sep 2018 16:53:53 -0500 Subject: PCI: Do not skip power-managed bridges in pci_enable_wake() Commit baecc470d5fd ("PCI / PM: Skip bridges in pci_enable_wake()") changed pci_enable_wake() so that all bridges are skipped when wakeup is enabled (or disabled) with the reasoning that bridges can only signal wakeup on behalf of their subordinate devices. However, there are bridges that can signal wakeup themselves. For example PCIe downstream and root ports supporting hotplug may signal wakeup upon hotplug event. For this reason change pci_enable_wake() so that it skips all bridges except those that we power manage (->bridge_d3 is set). Those are the ones that can go into low power states and may need to signal wakeup. Signed-off-by: Mika Westerberg Signed-off-by: Bjorn Helgaas Reviewed-by: Rafael J. Wysocki --- drivers/pci/pci.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) (limited to 'drivers/pci/pci.c') diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index 4b0b1d0548f0..4a1b1f76dc92 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -2137,10 +2137,13 @@ static int __pci_enable_wake(struct pci_dev *dev, pci_power_t state, bool enable int ret = 0; /* - * Bridges can only signal wakeup on behalf of subordinate devices, - * but that is set up elsewhere, so skip them. + * Bridges that are not power-manageable directly only signal + * wakeup on behalf of subordinate devices which is set up + * elsewhere, so skip them. However, bridges that are + * power-manageable may signal wakeup for themselves (for example, + * on a hotplug event) and they need to be covered here. */ - if (pci_has_subordinate(dev)) + if (!pci_power_manageable(dev)) return 0; /* Don't do the same thing twice in a row for one device. */ -- cgit v1.2.3 From 26ad34d510a87fc65caeb48fa85cce58d2477a88 Mon Sep 17 00:00:00 2001 From: Mika Westerberg Date: Thu, 27 Sep 2018 16:57:14 -0500 Subject: PCI / ACPI: Whitelist D3 for more PCIe hotplug ports In order to have better power management for Thunderbolt PCIe chains, Windows enables power management for native PCIe hotplug ports if there is the following ACPI _DSD attached to the root port: Name (_DSD, Package () { ToUUID ("6211e2c0-58a3-4af3-90e1-927a4e0c55a4"), Package () { Package () {"HotPlugSupportInD3", 1} } }) This is also documented in: https://docs.microsoft.com/en-us/windows-hardware/drivers/pci/dsd-for-pcie-root-ports#identifying-pcie-root-ports-supporting-hot-plug-in-d3 Do the same in Linux by introducing new firmware PM callback (->bridge_d3()) and then implement it for ACPI based systems so that the above property is checked. There is one catch, though. The initial pci_dev->bridge_d3 is set before the root port has ACPI companion bound (the device is not added to the PCI bus either) so we need to look up the ACPI companion manually in that case in acpi_pci_bridge_d3(). Signed-off-by: Mika Westerberg Signed-off-by: Bjorn Helgaas Reviewed-by: Rafael J. Wysocki --- drivers/acpi/property.c | 3 +++ drivers/pci/pci-acpi.c | 41 +++++++++++++++++++++++++++++++++++++++++ drivers/pci/pci.c | 9 +++++++++ drivers/pci/pci.h | 3 +++ 4 files changed, 56 insertions(+) (limited to 'drivers/pci/pci.c') diff --git a/drivers/acpi/property.c b/drivers/acpi/property.c index 90ba9371bae6..8c7c4583b52d 100644 --- a/drivers/acpi/property.c +++ b/drivers/acpi/property.c @@ -28,6 +28,9 @@ static const guid_t prp_guids[] = { /* ACPI _DSD device properties GUID: daffd814-6eba-4d8c-8a91-bc9bbf4aa301 */ GUID_INIT(0xdaffd814, 0x6eba, 0x4d8c, 0x8a, 0x91, 0xbc, 0x9b, 0xbf, 0x4a, 0xa3, 0x01), + /* Hotplug in D3 GUID: 6211e2c0-58a3-4af3-90e1-927a4e0c55a4 */ + GUID_INIT(0x6211e2c0, 0x58a3, 0x4af3, + 0x90, 0xe1, 0x92, 0x7a, 0x4e, 0x0c, 0x55, 0xa4), }; static const guid_t ads_guid = diff --git a/drivers/pci/pci-acpi.c b/drivers/pci/pci-acpi.c index f8436d1c4d45..c8d0549580f4 100644 --- a/drivers/pci/pci-acpi.c +++ b/drivers/pci/pci-acpi.c @@ -519,6 +519,46 @@ static pci_power_t acpi_pci_choose_state(struct pci_dev *pdev) return PCI_POWER_ERROR; } +static struct acpi_device *acpi_pci_find_companion(struct device *dev); + +static bool acpi_pci_bridge_d3(struct pci_dev *dev) +{ + const struct fwnode_handle *fwnode; + struct acpi_device *adev; + struct pci_dev *root; + u8 val; + + if (!dev->is_hotplug_bridge) + return false; + + /* + * Look for a special _DSD property for the root port and if it + * is set we know the hierarchy behind it supports D3 just fine. + */ + root = pci_find_pcie_root_port(dev); + if (!root) + return false; + + adev = ACPI_COMPANION(&root->dev); + if (root == dev) { + /* + * It is possible that the ACPI companion is not yet bound + * for the root port so look it up manually here. + */ + if (!adev && !pci_dev_is_added(root)) + adev = acpi_pci_find_companion(&root->dev); + } + + if (!adev) + return false; + + fwnode = acpi_fwnode_handle(adev); + if (fwnode_property_read_u8(fwnode, "HotPlugSupportInD3", &val)) + return false; + + return val == 1; +} + static bool acpi_pci_power_manageable(struct pci_dev *dev) { struct acpi_device *adev = ACPI_COMPANION(&dev->dev); @@ -635,6 +675,7 @@ static bool acpi_pci_need_resume(struct pci_dev *dev) } static const struct pci_platform_pm_ops acpi_pci_platform_pm = { + .bridge_d3 = acpi_pci_bridge_d3, .is_manageable = acpi_pci_power_manageable, .set_state = acpi_pci_set_power_state, .get_state = acpi_pci_get_power_state, diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index 4a1b1f76dc92..e6fcf11f5dcc 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -793,6 +793,11 @@ static inline bool platform_pci_need_resume(struct pci_dev *dev) return pci_platform_pm ? pci_platform_pm->need_resume(dev) : false; } +static inline bool platform_pci_bridge_d3(struct pci_dev *dev) +{ + return pci_platform_pm ? pci_platform_pm->bridge_d3(dev) : false; +} + /** * pci_raw_set_power_state - Use PCI PM registers to set the power state of * given PCI device @@ -2518,6 +2523,10 @@ bool pci_bridge_d3_possible(struct pci_dev *bridge) if (bridge->is_thunderbolt) return true; + /* Platform might know better if the bridge supports D3 */ + if (platform_pci_bridge_d3(bridge)) + return true; + /* * Hotplug ports handled natively by the OS were not validated * by vendors for runtime D3 at least until 2018 because there diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h index eb3125decffe..672ba4d1659e 100644 --- a/drivers/pci/pci.h +++ b/drivers/pci/pci.h @@ -40,6 +40,8 @@ int pci_bus_error_reset(struct pci_dev *dev); /** * struct pci_platform_pm_ops - Firmware PM callbacks * + * @bridge_d3: Does the bridge allow entering into D3 + * * @is_manageable: returns 'true' if given device is power manageable by the * platform firmware * @@ -61,6 +63,7 @@ int pci_bus_error_reset(struct pci_dev *dev); * these callbacks are mandatory. */ struct pci_platform_pm_ops { + bool (*bridge_d3)(struct pci_dev *dev); bool (*is_manageable)(struct pci_dev *dev); int (*set_state)(struct pci_dev *dev, pci_power_t state); pci_power_t (*get_state)(struct pci_dev *dev); -- cgit v1.2.3