diff options
Diffstat (limited to 'drivers/pci/pci.c')
| -rw-r--r-- | drivers/pci/pci.c | 384 | 
1 files changed, 262 insertions, 122 deletions
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index bd6f156dc3cf..e597655a5643 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -1,11 +1,11 @@  // SPDX-License-Identifier: GPL-2.0  /* - *	PCI Bus Services, see include/linux/pci.h for further explanation. + * PCI Bus Services, see include/linux/pci.h for further explanation.   * - *	Copyright 1993 -- 1997 Drew Eckhardt, Frederic Potter, - *	David Mosberger-Tang + * Copyright 1993 -- 1997 Drew Eckhardt, Frederic Potter, + * David Mosberger-Tang   * - *	Copyright 1997 -- 2000 Martin Mares <mj@ucw.cz> + * Copyright 1997 -- 2000 Martin Mares <mj@ucw.cz>   */  #include <linux/acpi.h> @@ -22,6 +22,7 @@  #include <linux/spinlock.h>  #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> @@ -126,6 +127,9 @@ static int __init pcie_port_pm_setup(char *str)  }  __setup("pcie_port_pm=", pcie_port_pm_setup); +/* Time to wait after a reset for device to become responsive */ +#define PCIE_RESET_READY_POLL_MS 60000 +  /**   * pci_bus_max_busnr - returns maximum PCI bus number of given bus' children   * @bus: pointer to PCI bus structure to search @@ -1684,6 +1688,15 @@ int pci_set_pcie_reset_state(struct pci_dev *dev, enum pcie_reset_state state)  EXPORT_SYMBOL_GPL(pci_set_pcie_reset_state);  /** + * pcie_clear_root_pme_status - Clear root port PME interrupt status. + * @dev: PCIe root port or event collector. + */ +void pcie_clear_root_pme_status(struct pci_dev *dev) +{ +	pcie_capability_set_dword(dev, PCI_EXP_RTSTA, PCI_EXP_RTSTA_PME); +} + +/**   * pci_check_pme_status - Check if given device has generated PME.   * @dev: Device to check.   * @@ -2258,8 +2271,6 @@ void pci_config_pm_runtime_put(struct pci_dev *pdev)   */  bool pci_bridge_d3_possible(struct pci_dev *bridge)  { -	unsigned int year; -  	if (!pci_is_pcie(bridge))  		return false; @@ -2287,10 +2298,8 @@ bool pci_bridge_d3_possible(struct pci_dev *bridge)  		 * It should be safe to put PCIe ports from 2015 or newer  		 * to D3.  		 */ -		if (dmi_get_date(DMI_BIOS_DATE, &year, NULL, NULL) && -		    year >= 2015) { +		if (dmi_get_bios_year() >= 2015)  			return true; -		}  		break;  	} @@ -3440,68 +3449,35 @@ int pci_request_regions_exclusive(struct pci_dev *pdev, const char *res_name)  }  EXPORT_SYMBOL(pci_request_regions_exclusive); -#ifdef PCI_IOBASE -struct io_range { -	struct list_head list; -	phys_addr_t start; -	resource_size_t size; -}; - -static LIST_HEAD(io_range_list); -static DEFINE_SPINLOCK(io_range_lock); -#endif -  /*   * Record the PCI IO range (expressed as CPU physical address + size).   * Return a negative value if an error has occured, zero otherwise   */ -int __weak pci_register_io_range(phys_addr_t addr, resource_size_t size) +int pci_register_io_range(struct fwnode_handle *fwnode, phys_addr_t addr, +			resource_size_t	size)  { -	int err = 0; - +	int ret = 0;  #ifdef PCI_IOBASE -	struct io_range *range; -	resource_size_t allocated_size = 0; - -	/* check if the range hasn't been previously recorded */ -	spin_lock(&io_range_lock); -	list_for_each_entry(range, &io_range_list, list) { -		if (addr >= range->start && addr + size <= range->start + size) { -			/* range already registered, bail out */ -			goto end_register; -		} -		allocated_size += range->size; -	} - -	/* range not registed yet, check for available space */ -	if (allocated_size + size - 1 > IO_SPACE_LIMIT) { -		/* if it's too big check if 64K space can be reserved */ -		if (allocated_size + SZ_64K - 1 > IO_SPACE_LIMIT) { -			err = -E2BIG; -			goto end_register; -		} +	struct logic_pio_hwaddr *range; -		size = SZ_64K; -		pr_warn("Requested IO range too big, new size set to 64K\n"); -	} +	if (!size || addr + size < addr) +		return -EINVAL; -	/* add the range to the list */  	range = kzalloc(sizeof(*range), GFP_ATOMIC); -	if (!range) { -		err = -ENOMEM; -		goto end_register; -	} +	if (!range) +		return -ENOMEM; -	range->start = addr; +	range->fwnode = fwnode;  	range->size = size; +	range->hw_start = addr; +	range->flags = LOGIC_PIO_CPU_MMIO; -	list_add_tail(&range->list, &io_range_list); - -end_register: -	spin_unlock(&io_range_lock); +	ret = logic_pio_register_range(range); +	if (ret) +		kfree(range);  #endif -	return err; +	return ret;  }  phys_addr_t pci_pio_to_address(unsigned long pio) @@ -3509,21 +3485,10 @@ phys_addr_t pci_pio_to_address(unsigned long pio)  	phys_addr_t address = (phys_addr_t)OF_BAD_ADDR;  #ifdef PCI_IOBASE -	struct io_range *range; -	resource_size_t allocated_size = 0; - -	if (pio > IO_SPACE_LIMIT) +	if (pio >= MMIO_UPPER_LIMIT)  		return address; -	spin_lock(&io_range_lock); -	list_for_each_entry(range, &io_range_list, list) { -		if (pio >= allocated_size && pio < allocated_size + range->size) { -			address = range->start + pio - allocated_size; -			break; -		} -		allocated_size += range->size; -	} -	spin_unlock(&io_range_lock); +	address = logic_pio_to_hwaddr(pio);  #endif  	return address; @@ -3532,21 +3497,7 @@ phys_addr_t pci_pio_to_address(unsigned long pio)  unsigned long __weak pci_address_to_pio(phys_addr_t address)  {  #ifdef PCI_IOBASE -	struct io_range *res; -	resource_size_t offset = 0; -	unsigned long addr = -1; - -	spin_lock(&io_range_lock); -	list_for_each_entry(res, &io_range_list, list) { -		if (address >= res->start && address < res->start + res->size) { -			addr = address - res->start + offset; -			break; -		} -		offset += res->size; -	} -	spin_unlock(&io_range_lock); - -	return addr; +	return logic_pio_trans_cpuaddr(address);  #else  	if (address > IO_SPACE_LIMIT)  		return (unsigned long)-1; @@ -4017,20 +3968,13 @@ int pci_wait_for_pending_transaction(struct pci_dev *dev)  }  EXPORT_SYMBOL(pci_wait_for_pending_transaction); -static void pci_flr_wait(struct pci_dev *dev) +static int pci_dev_wait(struct pci_dev *dev, char *reset_type, int timeout)  { -	int delay = 1, timeout = 60000; +	int delay = 1;  	u32 id;  	/* -	 * Per PCIe r3.1, sec 6.6.2, a device must complete an FLR within -	 * 100ms, but may silently discard requests while the FLR is in -	 * progress.  Wait 100ms before trying to access the device. -	 */ -	msleep(100); - -	/* -	 * After 100ms, the device should not silently discard config +	 * After reset, the device should not silently discard config  	 * requests, but it may still indicate that it needs more time by  	 * responding to them with CRS completions.  The Root Port will  	 * generally synthesize ~0 data to complete the read (except when @@ -4044,14 +3988,14 @@ static void pci_flr_wait(struct pci_dev *dev)  	pci_read_config_dword(dev, PCI_COMMAND, &id);  	while (id == ~0) {  		if (delay > timeout) { -			pci_warn(dev, "not ready %dms after FLR; giving up\n", -				 100 + delay - 1); -			return; +			pci_warn(dev, "not ready %dms after %s; giving up\n", +				 delay - 1, reset_type); +			return -ENOTTY;  		}  		if (delay > 1000) -			pci_info(dev, "not ready %dms after FLR; waiting\n", -				 100 + delay - 1); +			pci_info(dev, "not ready %dms after %s; waiting\n", +				 delay - 1, reset_type);  		msleep(delay);  		delay *= 2; @@ -4059,7 +4003,10 @@ static void pci_flr_wait(struct pci_dev *dev)  	}  	if (delay > 1000) -		pci_info(dev, "ready %dms after FLR\n", 100 + delay - 1); +		pci_info(dev, "ready %dms after %s\n", delay - 1, +			 reset_type); + +	return 0;  }  /** @@ -4088,13 +4035,21 @@ static bool pcie_has_flr(struct pci_dev *dev)   * device supports FLR before calling this function, e.g. by using the   * pcie_has_flr() helper.   */ -void pcie_flr(struct pci_dev *dev) +int pcie_flr(struct pci_dev *dev)  {  	if (!pci_wait_for_pending_transaction(dev))  		pci_err(dev, "timed out waiting for pending transaction; performing function level reset anyway\n");  	pcie_capability_set_word(dev, PCI_EXP_DEVCTL, PCI_EXP_DEVCTL_BCR_FLR); -	pci_flr_wait(dev); + +	/* +	 * 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 +	 * progress.  Wait 100ms before trying to access the device. +	 */ +	msleep(100); + +	return pci_dev_wait(dev, "FLR", PCIE_RESET_READY_POLL_MS);  }  EXPORT_SYMBOL_GPL(pcie_flr); @@ -4127,8 +4082,16 @@ static int pci_af_flr(struct pci_dev *dev, int probe)  		pci_err(dev, "timed out waiting for pending transaction; performing AF function level reset anyway\n");  	pci_write_config_byte(dev, pos + PCI_AF_CTRL, PCI_AF_CTRL_FLR); -	pci_flr_wait(dev); -	return 0; + +	/* +	 * Per Advanced Capabilities for Conventional PCI ECN, 13 April 2006, +	 * updated 27 July 2006; a device must complete an FLR within +	 * 100ms, but may silently discard requests while the FLR is in +	 * progress.  Wait 100ms before trying to access the device. +	 */ +	msleep(100); + +	return pci_dev_wait(dev, "AF_FLR", PCIE_RESET_READY_POLL_MS);  }  /** @@ -4173,7 +4136,7 @@ static int pci_pm_reset(struct pci_dev *dev, int probe)  	pci_write_config_word(dev, dev->pm_cap + PCI_PM_CTRL, csr);  	pci_dev_d3_sleep(dev); -	return 0; +	return pci_dev_wait(dev, "PM D3->D0", PCIE_RESET_READY_POLL_MS);  }  void pci_reset_secondary_bus(struct pci_dev *dev) @@ -4183,6 +4146,7 @@ void pci_reset_secondary_bus(struct pci_dev *dev)  	pci_read_config_word(dev, PCI_BRIDGE_CONTROL, &ctrl);  	ctrl |= PCI_BRIDGE_CTL_BUS_RESET;  	pci_write_config_word(dev, PCI_BRIDGE_CONTROL, ctrl); +  	/*  	 * PCI spec v3.0 7.6.4.2 requires minimum Trst of 1ms.  Double  	 * this to 2ms to ensure that we meet the minimum requirement. @@ -4214,9 +4178,11 @@ void __weak pcibios_reset_secondary_bus(struct pci_dev *dev)   * Use the bridge control register to assert reset on the secondary bus.   * Devices on the secondary bus are left in power-on state.   */ -void pci_reset_bridge_secondary_bus(struct pci_dev *dev) +int pci_reset_bridge_secondary_bus(struct pci_dev *dev)  {  	pcibios_reset_secondary_bus(dev); + +	return pci_dev_wait(dev, "bus reset", PCIE_RESET_READY_POLL_MS);  }  EXPORT_SYMBOL_GPL(pci_reset_bridge_secondary_bus); @@ -4379,8 +4345,9 @@ int __pci_reset_function_locked(struct pci_dev *dev)  	if (rc != -ENOTTY)  		return rc;  	if (pcie_has_flr(dev)) { -		pcie_flr(dev); -		return 0; +		rc = pcie_flr(dev); +		if (rc != -ENOTTY) +			return rc;  	}  	rc = pci_af_flr(dev, 0);  	if (rc != -ENOTTY) @@ -4450,9 +4417,8 @@ int pci_reset_function(struct pci_dev *dev)  {  	int rc; -	rc = pci_probe_reset_function(dev); -	if (rc) -		return rc; +	if (!dev->reset_fn) +		return -ENOTTY;  	pci_dev_lock(dev);  	pci_dev_save_and_disable(dev); @@ -4487,9 +4453,8 @@ int pci_reset_function_locked(struct pci_dev *dev)  {  	int rc; -	rc = pci_probe_reset_function(dev); -	if (rc) -		return rc; +	if (!dev->reset_fn) +		return -ENOTTY;  	pci_dev_save_and_disable(dev); @@ -4511,18 +4476,17 @@ int pci_try_reset_function(struct pci_dev *dev)  {  	int rc; -	rc = pci_probe_reset_function(dev); -	if (rc) -		return rc; +	if (!dev->reset_fn) +		return -ENOTTY;  	if (!pci_dev_trylock(dev))  		return -EAGAIN;  	pci_dev_save_and_disable(dev);  	rc = __pci_reset_function_locked(dev); +	pci_dev_restore(dev);  	pci_dev_unlock(dev); -	pci_dev_restore(dev);  	return rc;  }  EXPORT_SYMBOL_GPL(pci_try_reset_function); @@ -4730,7 +4694,9 @@ static void pci_slot_restore(struct pci_slot *slot)  	list_for_each_entry(dev, &slot->bus->devices, bus_list) {  		if (!dev->slot || dev->slot != slot)  			continue; +		pci_dev_lock(dev);  		pci_dev_restore(dev); +		pci_dev_unlock(dev);  		if (dev->subordinate)  			pci_bus_restore(dev->subordinate);  	} @@ -5147,6 +5113,180 @@ int pcie_get_minimum_link(struct pci_dev *dev, enum pci_bus_speed *speed,  EXPORT_SYMBOL(pcie_get_minimum_link);  /** + * pcie_bandwidth_available - determine minimum link settings of a PCIe + *			      device and its bandwidth limitation + * @dev: PCI device to query + * @limiting_dev: storage for device causing the bandwidth limitation + * @speed: storage for speed of limiting device + * @width: storage for width of limiting device + * + * Walk up the PCI device chain and find the point where the minimum + * bandwidth is available.  Return the bandwidth available there and (if + * limiting_dev, speed, and width pointers are supplied) information about + * that point.  The bandwidth returned is in Mb/s, i.e., megabits/second of + * raw bandwidth. + */ +u32 pcie_bandwidth_available(struct pci_dev *dev, struct pci_dev **limiting_dev, +			     enum pci_bus_speed *speed, +			     enum pcie_link_width *width) +{ +	u16 lnksta; +	enum pci_bus_speed next_speed; +	enum pcie_link_width next_width; +	u32 bw, next_bw; + +	if (speed) +		*speed = PCI_SPEED_UNKNOWN; +	if (width) +		*width = PCIE_LNK_WIDTH_UNKNOWN; + +	bw = 0; + +	while (dev) { +		pcie_capability_read_word(dev, PCI_EXP_LNKSTA, &lnksta); + +		next_speed = pcie_link_speed[lnksta & PCI_EXP_LNKSTA_CLS]; +		next_width = (lnksta & PCI_EXP_LNKSTA_NLW) >> +			PCI_EXP_LNKSTA_NLW_SHIFT; + +		next_bw = next_width * PCIE_SPEED2MBS_ENC(next_speed); + +		/* Check if current device limits the total bandwidth */ +		if (!bw || next_bw <= bw) { +			bw = next_bw; + +			if (limiting_dev) +				*limiting_dev = dev; +			if (speed) +				*speed = next_speed; +			if (width) +				*width = next_width; +		} + +		dev = pci_upstream_bridge(dev); +	} + +	return bw; +} +EXPORT_SYMBOL(pcie_bandwidth_available); + +/** + * pcie_get_speed_cap - query for the PCI device's link speed capability + * @dev: PCI device to query + * + * Query the PCI device speed capability.  Return the maximum link speed + * supported by the device. + */ +enum pci_bus_speed pcie_get_speed_cap(struct pci_dev *dev) +{ +	u32 lnkcap2, lnkcap; + +	/* +	 * PCIe r4.0 sec 7.5.3.18 recommends using the Supported Link +	 * Speeds Vector in Link Capabilities 2 when supported, falling +	 * back to Max Link Speed in Link Capabilities otherwise. +	 */ +	pcie_capability_read_dword(dev, PCI_EXP_LNKCAP2, &lnkcap2); +	if (lnkcap2) { /* PCIe r3.0-compliant */ +		if (lnkcap2 & PCI_EXP_LNKCAP2_SLS_16_0GB) +			return PCIE_SPEED_16_0GT; +		else if (lnkcap2 & PCI_EXP_LNKCAP2_SLS_8_0GB) +			return PCIE_SPEED_8_0GT; +		else if (lnkcap2 & PCI_EXP_LNKCAP2_SLS_5_0GB) +			return PCIE_SPEED_5_0GT; +		else if (lnkcap2 & PCI_EXP_LNKCAP2_SLS_2_5GB) +			return PCIE_SPEED_2_5GT; +		return PCI_SPEED_UNKNOWN; +	} + +	pcie_capability_read_dword(dev, PCI_EXP_LNKCAP, &lnkcap); +	if (lnkcap) { +		if (lnkcap & PCI_EXP_LNKCAP_SLS_16_0GB) +			return PCIE_SPEED_16_0GT; +		else if (lnkcap & PCI_EXP_LNKCAP_SLS_8_0GB) +			return PCIE_SPEED_8_0GT; +		else if (lnkcap & PCI_EXP_LNKCAP_SLS_5_0GB) +			return PCIE_SPEED_5_0GT; +		else if (lnkcap & PCI_EXP_LNKCAP_SLS_2_5GB) +			return PCIE_SPEED_2_5GT; +	} + +	return PCI_SPEED_UNKNOWN; +} + +/** + * pcie_get_width_cap - query for the PCI device's link width capability + * @dev: PCI device to query + * + * Query the PCI device width capability.  Return the maximum link width + * supported by the device. + */ +enum pcie_link_width pcie_get_width_cap(struct pci_dev *dev) +{ +	u32 lnkcap; + +	pcie_capability_read_dword(dev, PCI_EXP_LNKCAP, &lnkcap); +	if (lnkcap) +		return (lnkcap & PCI_EXP_LNKCAP_MLW) >> 4; + +	return PCIE_LNK_WIDTH_UNKNOWN; +} + +/** + * pcie_bandwidth_capable - calculate a PCI device's link bandwidth capability + * @dev: PCI device + * @speed: storage for link speed + * @width: storage for link width + * + * Calculate a PCI device's link bandwidth by querying for its link speed + * and width, multiplying them, and applying encoding overhead.  The result + * is in Mb/s, i.e., megabits/second of raw bandwidth. + */ +u32 pcie_bandwidth_capable(struct pci_dev *dev, enum pci_bus_speed *speed, +			   enum pcie_link_width *width) +{ +	*speed = pcie_get_speed_cap(dev); +	*width = pcie_get_width_cap(dev); + +	if (*speed == PCI_SPEED_UNKNOWN || *width == PCIE_LNK_WIDTH_UNKNOWN) +		return 0; + +	return *width * PCIE_SPEED2MBS_ENC(*speed); +} + +/** + * 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.  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. + */ +void pcie_print_link_status(struct pci_dev *dev) +{ +	enum pcie_link_width width, width_cap; +	enum pci_bus_speed speed, speed_cap; +	struct pci_dev *limiting_dev = NULL; +	u32 bw_avail, bw_cap; + +	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) +		pci_info(dev, "%u.%03u Gb/s available bandwidth (%s x%d link)\n", +			 bw_cap / 1000, bw_cap % 1000, +			 PCIE_SPEED2STR(speed_cap), width_cap); +	else +		pci_info(dev, "%u.%03u Gb/s available 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, +			 limiting_dev ? pci_name(limiting_dev) : "<unknown>", +			 bw_cap / 1000, bw_cap % 1000, +			 PCIE_SPEED2STR(speed_cap), width_cap); +} +EXPORT_SYMBOL(pcie_print_link_status); + +/**   * pci_select_bars - Make BAR mask from the type of resource   * @dev: the PCI device for which BAR mask is made   * @flags: resource type mask to be selected @@ -5488,7 +5628,6 @@ void pci_reassigndev_resource_alignment(struct pci_dev *dev)  		return;  	} -	pci_info(dev, "Disabling memory decoding and releasing memory resources\n");  	pci_read_config_word(dev, PCI_COMMAND, &command);  	command &= ~PCI_COMMAND_MEMORY;  	pci_write_config_word(dev, PCI_COMMAND, command); @@ -5611,8 +5750,9 @@ static int of_pci_bus_find_domain_nr(struct device *parent)  		use_dt_domains = 0;  		domain = pci_get_new_domain_nr();  	} else { -		dev_err(parent, "Node %pOF has inconsistent \"linux,pci-domain\" property in DT\n", -			parent->of_node); +		if (parent) +			pr_err("Node %pOF has ", parent->of_node); +		pr_err("Inconsistent \"linux,pci-domain\" property in DT\n");  		domain = -1;  	}  | 
