From 6fbf9e7a90862988c278462d85ce9684605a52b2 Mon Sep 17 00:00:00 2001 From: Konrad Rzeszutek Wilk Date: Thu, 12 Jan 2012 12:06:46 -0500 Subject: PCI: Introduce __pci_reset_function_locked to be used when holding device_lock. The use case of this is when a driver wants to call FLR when a device is attached to it using the SysFS "bind" or "unbind" functionality. The call chain when a user does "bind" looks as so: echo "0000:01.07.0" > /sys/bus/pci/drivers/XXXX/bind and ends up calling: driver_bind: device_lock(dev); <=== TAKES LOCK XXXX_probe: .. pci_enable_device() ...__pci_reset_function(), which calls pci_dev_reset(dev, 0): if (!0) { device_lock(dev) <==== DEADLOCK The __pci_reset_function_locked function allows the the drivers 'probe' function to call the "pci_reset_function" while still holding the driver mutex lock. Signed-off-by: Konrad Rzeszutek Wilk Signed-off-by: Jesse Barnes --- drivers/pci/pci.c | 25 +++++++++++++++++++++++++ 1 file changed, 25 insertions(+) (limited to 'drivers/pci/pci.c') diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index af295bb21d6..053670e09e2 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -3162,6 +3162,31 @@ int __pci_reset_function(struct pci_dev *dev) } EXPORT_SYMBOL_GPL(__pci_reset_function); +/** + * __pci_reset_function_locked - reset a PCI device function while holding + * the @dev mutex lock. + * @dev: PCI device to reset + * + * Some devices allow an individual function to be reset without affecting + * other functions in the same device. The PCI device must be responsive + * to PCI config space in order to use this function. + * + * The device function is presumed to be unused and the caller is holding + * the device mutex lock when this function is called. + * Resetting the device will make the contents of PCI configuration space + * random, so any caller of this must be prepared to reinitialise the + * device including MSI, bus mastering, BARs, decoding IO and memory spaces, + * etc. + * + * Returns 0 if the device function was successfully reset or negative if the + * device doesn't support resetting a single function. + */ +int __pci_reset_function_locked(struct pci_dev *dev) +{ + return pci_dev_reset(dev, 1); +} +EXPORT_SYMBOL_GPL(__pci_reset_function_locked); + /** * pci_probe_reset_function - check whether the device can be safely reset * @dev: PCI device to reset -- cgit v1.2.3-70-g09d2 From 26f41062f28de65e11d3cf353e52d0be73442be1 Mon Sep 17 00:00:00 2001 From: "Kay, Allen M" Date: Thu, 26 Jan 2012 10:25:53 -0800 Subject: PCI: check for pci bar restore completion and retry On some OEM systems, pci_restore_state() is called while FLR has not yet completed. As a result, PCI BAR register restore is not successful. This fix reads back the restored value and compares it with saved value and re-tries 10 times before giving up. Signed-off-by: Jean Guyader Signed-off-by: Eric Chanudet Signed-off-by: Allen Kay Signed-off-by: Jesse Barnes --- drivers/pci/pci.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) (limited to 'drivers/pci/pci.c') diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index 053670e09e2..9c89447e7b2 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -959,6 +959,7 @@ void pci_restore_state(struct pci_dev *dev) { int i; u32 val; + int tries; if (!dev->state_saved) return; @@ -973,12 +974,16 @@ void pci_restore_state(struct pci_dev *dev) */ for (i = 15; i >= 0; i--) { pci_read_config_dword(dev, i * 4, &val); - if (val != dev->saved_config_space[i]) { + tries = 10; + while (tries && val != dev->saved_config_space[i]) { dev_dbg(&dev->dev, "restoring config " "space at offset %#x (was %#x, writing %#x)\n", i, val, (int)dev->saved_config_space[i]); pci_write_config_dword(dev,i * 4, dev->saved_config_space[i]); + pci_read_config_dword(dev, i * 4, &val); + mdelay(10); + tries--; } } pci_restore_pcix_state(dev); -- cgit v1.2.3-70-g09d2 From f796841e49fe086176e27ed0e1f3f7a1123a4a6b Mon Sep 17 00:00:00 2001 From: Yinghai Lu Date: Sat, 11 Feb 2012 00:18:30 -0800 Subject: PCI: fix memleak for pci dev removing during hotplug unreferenced object 0xffff880276d17700 (size 64): comm "swapper/0", pid 1, jiffies 4294897182 (age 3976.028s) hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 18 f9 de 76 02 88 ff ff ...........v.... 10 00 00 00 0e 00 00 00 0f 28 40 00 00 00 00 00 .........(@..... backtrace: [] kmemleak_alloc+0x26/0x43 [] __kmalloc+0x121/0x183 [] pci_add_cap_save_buffer+0x35/0x7c [] pci_allocate_cap_save_buffers+0x1d/0x65 [] pci_device_add+0x92/0xf1 [] pci_scan_single_device+0x9f/0xa1 [] pci_scan_slot.part.20+0x21/0x106 [] pci_scan_slot+0x2b/0x35 [] __pci_scan_child_bus+0x51/0x107 [] pci_scan_bridge+0x376/0x6ae [] __pci_scan_child_bus+0xcd/0x107 [] pci_scan_child_bus+0x11/0x2a [] pci_acpi_scan_root+0x18b/0x21c [] acpi_pci_root_add+0x1e1/0x42a [] acpi_device_probe+0x50/0x190 [] really_probe+0x99/0x126 Need to free saved_buffer for capabilities. Signed-off-by: Yinghai Lu Signed-off-by: Jesse Barnes --- drivers/pci/pci.c | 9 +++++++++ drivers/pci/pci.h | 1 + drivers/pci/probe.c | 1 + 3 files changed, 11 insertions(+) (limited to 'drivers/pci/pci.c') diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index 9c89447e7b2..e7dfcd44757 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -1916,6 +1916,15 @@ void pci_allocate_cap_save_buffers(struct pci_dev *dev) "unable to preallocate PCI-X save buffer\n"); } +void pci_free_cap_save_buffers(struct pci_dev *dev) +{ + struct pci_cap_saved_state *tmp; + struct hlist_node *pos, *n; + + hlist_for_each_entry_safe(tmp, pos, n, &dev->saved_cap_space, next) + kfree(tmp); +} + /** * pci_enable_ari - enable ARI forwarding if hardware support it * @dev: the PCI device diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h index aaf7ff8c517..586ac9b097e 100644 --- a/drivers/pci/pci.h +++ b/drivers/pci/pci.h @@ -73,6 +73,7 @@ extern int __pci_pme_wakeup(struct pci_dev *dev, void *ign); extern void pci_pm_init(struct pci_dev *dev); extern void platform_pci_wakeup_init(struct pci_dev *dev); extern void pci_allocate_cap_save_buffers(struct pci_dev *dev); +void pci_free_cap_save_buffers(struct pci_dev *dev); static inline void pci_wakeup_event(struct pci_dev *dev) { diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c index aa9b1dec0d3..dc904bd4b56 100644 --- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -1024,6 +1024,7 @@ static void pci_release_capabilities(struct pci_dev *dev) { pci_vpd_release(dev); pci_iov_release(dev); + pci_free_cap_save_buffers(dev); } /** -- cgit v1.2.3-70-g09d2 From 34a4876e3071ddebf3c98c99ba01c14b059a1361 Mon Sep 17 00:00:00 2001 From: Yinghai Lu Date: Sat, 11 Feb 2012 00:18:41 -0800 Subject: PCI: move pci_find_saved_cap out of linux/pci.h Only one user in driver/pci/pci.c, so we don't need to put it in global pci.h Reviewed-by: Bjorn Helgaas Signed-off-by: Yinghai Lu Signed-off-by: Jesse Barnes --- drivers/pci/pci.c | 19 +++++++++++++++++++ include/linux/pci.h | 19 ------------------- 2 files changed, 19 insertions(+), 19 deletions(-) (limited to 'drivers/pci/pci.c') diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index e7dfcd44757..8f30736dbf3 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -825,6 +825,19 @@ EXPORT_SYMBOL(pci_choose_state); #define pcie_cap_has_sltctl2(type, flags) \ ((flags & PCI_EXP_FLAGS_VERS) > 1) +static struct pci_cap_saved_state *pci_find_saved_cap( + struct pci_dev *pci_dev, char cap) +{ + struct pci_cap_saved_state *tmp; + struct hlist_node *pos; + + hlist_for_each_entry(tmp, pos, &pci_dev->saved_cap_space, next) { + if (tmp->cap.cap_nr == cap) + return tmp; + } + return NULL; +} + static int pci_save_pcie_state(struct pci_dev *dev) { int pos, i = 0; @@ -1869,6 +1882,12 @@ void platform_pci_wakeup_init(struct pci_dev *dev) platform_pci_sleep_wake(dev, false); } +static void pci_add_saved_cap(struct pci_dev *pci_dev, + struct pci_cap_saved_state *new_cap) +{ + hlist_add_head(&new_cap->next, &pci_dev->saved_cap_space); +} + /** * pci_add_save_buffer - allocate buffer for saving given capability registers * @dev: the PCI device diff --git a/include/linux/pci.h b/include/linux/pci.h index f8caaab4b3f..bcaa51ca785 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -368,25 +368,6 @@ static inline int pci_channel_offline(struct pci_dev *pdev) return (pdev->error_state != pci_channel_io_normal); } -static inline struct pci_cap_saved_state *pci_find_saved_cap( - struct pci_dev *pci_dev, char cap) -{ - struct pci_cap_saved_state *tmp; - struct hlist_node *pos; - - hlist_for_each_entry(tmp, pos, &pci_dev->saved_cap_space, next) { - if (tmp->cap.cap_nr == cap) - return tmp; - } - return NULL; -} - -static inline void pci_add_saved_cap(struct pci_dev *pci_dev, - struct pci_cap_saved_state *new_cap) -{ - hlist_add_head(&new_cap->next, &pci_dev->saved_cap_space); -} - /* * The first PCI_BRIDGE_RESOURCE_NUM PCI bus resources (those that correspond * to P2P or CardBus bridge windows) go in a table. Additional ones (for -- cgit v1.2.3-70-g09d2 From b55438fdd5173a367659a7e200acea6c9f77b8cb Mon Sep 17 00:00:00 2001 From: Yinghai Lu Date: Thu, 23 Feb 2012 19:23:30 -0800 Subject: PCI: prepare pci=realloc for multiple options Let the user could enable and disable with pci=realloc=on or pci=realloc=off Also 1. move variable and functions near the place they are used. 2. change macro to function 3. change related functions and variable to static and _init 4. update parameter description accordingly. This will let us add a config option to control default behavior, and still allow the user to turn off automatic reallocation if it fails on their platform until a permanent solution is found. -v2: still honor pci=realloc, and treat it as pci=realloc=on also use enum instead of ... -v3: update kernel-paramenters.txt according to Jesse. Signed-off-by: Yinghai Lu Acked-by: Jesse Barnes Signed-off-by: Jesse Barnes --- Documentation/kernel-parameters.txt | 9 +++++++-- drivers/pci/pci.c | 4 +++- drivers/pci/pci.h | 2 +- drivers/pci/setup-bus.c | 34 +++++++++++++++++++++++++++------- 4 files changed, 38 insertions(+), 11 deletions(-) (limited to 'drivers/pci/pci.c') diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 7fb7a4b161f..7dc523e082a 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -2109,8 +2109,13 @@ bytes respectively. Such letter suffixes can also be entirely omitted. the default. off: Turn ECRC off on: Turn ECRC on. - realloc reallocate PCI resources if allocations done by BIOS - are erroneous. + realloc= Enable/disable reallocating PCI bridge resources + if allocations done by BIOS are too small to + accommodate resources required by all child + devices. + off: Turn realloc off + on: Turn realloc on + realloc same as realloc=on pcie_aspm= [PCIE] Forcibly enable or disable PCIe Active State Power Management. diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index 8f30736dbf3..e9f9dc183cf 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -3772,8 +3772,10 @@ static int __init pci_setup(char *str) pci_no_msi(); } else if (!strcmp(str, "noaer")) { pci_no_aer(); + } else if (!strncmp(str, "realloc=", 8)) { + pci_realloc_get_opt(str + 8); } else if (!strncmp(str, "realloc", 7)) { - pci_realloc(); + pci_realloc_get_opt("on"); } else if (!strcmp(str, "nodomains")) { pci_no_domains(); } else if (!strncmp(str, "cbiosize=", 9)) { diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h index 586ac9b097e..1fc63b39f83 100644 --- a/drivers/pci/pci.h +++ b/drivers/pci/pci.h @@ -149,7 +149,7 @@ static inline void pci_no_msi(void) { } static inline void pci_msi_init_pci_dev(struct pci_dev *dev) { } #endif -extern void pci_realloc(void); +void pci_realloc_get_opt(char *); static inline int pci_no_d1d2(struct pci_dev *dev) { diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c index 162edfb356b..219722df68d 100644 --- a/drivers/pci/setup-bus.c +++ b/drivers/pci/setup-bus.c @@ -48,13 +48,6 @@ static void free_list(struct list_head *head) } } -int pci_realloc_enable = 0; -#define pci_realloc_enabled() pci_realloc_enable -void pci_realloc(void) -{ - pci_realloc_enable = 1; -} - /** * add_to_list() - add a new resource tracker to the list * @head: Head of the list @@ -1273,6 +1266,33 @@ static int __init pci_get_max_depth(void) return depth; } +/* + * -1: undefined, will auto detect later + * 0: disabled by user + * 1: disabled by auto detect + * 2: enabled by user + * 3: enabled by auto detect + */ +enum enable_type { + undefined = -1, + user_disabled, + auto_disabled, + user_enabled, + auto_enabled, +}; + +static enum enable_type pci_realloc_enable __initdata = undefined; +void __init pci_realloc_get_opt(char *str) +{ + if (!strncmp(str, "off", 3)) + pci_realloc_enable = user_disabled; + else if (!strncmp(str, "on", 2)) + pci_realloc_enable = user_enabled; +} +static bool __init pci_realloc_enabled(void) +{ + return pci_realloc_enable >= user_enabled; +} /* * first try will not touch pci bridge res -- cgit v1.2.3-70-g09d2 From 2069ecfbe14ebd71a6f98e8a00724e9adf4fe4ee Mon Sep 17 00:00:00 2001 From: Yinghai Lu Date: Wed, 15 Feb 2012 21:40:31 -0800 Subject: PCI: Move "pci reassigndev resource alignment" out of quirks.c This isn't really a quirk; calling it directly from pci_add_device makes more sense. Signed-off-by: Yinghai Lu Signed-off-by: Jesse Barnes --- drivers/pci/pci.c | 62 ++++++++++++++++++++++++++++++++++++++++++++++++ drivers/pci/pci.h | 5 +--- drivers/pci/probe.c | 3 +++ drivers/pci/quirks.c | 63 ------------------------------------------------- drivers/pci/setup-res.c | 4 ---- 5 files changed, 66 insertions(+), 71 deletions(-) (limited to 'drivers/pci/pci.c') diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index e9f9dc183cf..b832f0fece9 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -3694,6 +3694,68 @@ int pci_is_reassigndev(struct pci_dev *dev) return (pci_specified_resource_alignment(dev) != 0); } +/* + * This function disables memory decoding and releases memory resources + * of the device specified by kernel's boot parameter 'pci=resource_alignment='. + * It also rounds up size to specified alignment. + * Later on, the kernel will assign page-aligned memory resource back + * to the device. + */ +void pci_reassigndev_resource_alignment(struct pci_dev *dev) +{ + int i; + struct resource *r; + resource_size_t align, size; + u16 command; + + if (!pci_is_reassigndev(dev)) + return; + + if (dev->hdr_type == PCI_HEADER_TYPE_NORMAL && + (dev->class >> 8) == PCI_CLASS_BRIDGE_HOST) { + dev_warn(&dev->dev, + "Can't reassign resources to host bridge.\n"); + return; + } + + dev_info(&dev->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); + + align = pci_specified_resource_alignment(dev); + for (i = 0; i < PCI_BRIDGE_RESOURCES; i++) { + r = &dev->resource[i]; + if (!(r->flags & IORESOURCE_MEM)) + continue; + size = resource_size(r); + if (size < align) { + size = align; + dev_info(&dev->dev, + "Rounding up size of resource #%d to %#llx.\n", + i, (unsigned long long)size); + } + r->end = size - 1; + r->start = 0; + } + /* Need to disable bridge's resource window, + * to enable the kernel to reassign new resource + * window later on. + */ + if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE && + (dev->class >> 8) == PCI_CLASS_BRIDGE_PCI) { + for (i = PCI_BRIDGE_RESOURCES; i < PCI_NUM_RESOURCES; i++) { + r = &dev->resource[i]; + if (!(r->flags & IORESOURCE_MEM)) + continue; + r->end = resource_size(r) - 1; + r->start = 0; + } + pci_disable_bridge_window(dev); + } +} + ssize_t pci_set_resource_alignment_param(const char *buf, size_t count) { if (count > RESOURCE_ALIGNMENT_PARAM_SIZE - 1) diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h index 1fc63b39f83..e4943479b23 100644 --- a/drivers/pci/pci.h +++ b/drivers/pci/pci.h @@ -228,11 +228,8 @@ static inline int pci_ari_enabled(struct pci_bus *bus) return bus->self && bus->self->ari_enabled; } -#ifdef CONFIG_PCI_QUIRKS -extern int pci_is_reassigndev(struct pci_dev *dev); -resource_size_t pci_specified_resource_alignment(struct pci_dev *dev); +void pci_reassigndev_resource_alignment(struct pci_dev *dev); extern void pci_disable_bridge_window(struct pci_dev *dev); -#endif /* Single Root I/O Virtualization */ struct pci_sriov { diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c index 36c22032ea1..944e05a66b9 100644 --- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -1325,6 +1325,9 @@ void pci_device_add(struct pci_dev *dev, struct pci_bus *bus) /* Fix up broken headers */ pci_fixup_device(pci_fixup_header, dev); + /* moved out from quirk header fixup code */ + pci_reassigndev_resource_alignment(dev); + /* Clear the state_saved flag. */ dev->state_saved = false; diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c index e198589d099..f8f81d4f29f 100644 --- a/drivers/pci/quirks.c +++ b/drivers/pci/quirks.c @@ -31,69 +31,6 @@ #include /* isa_dma_bridge_buggy */ #include "pci.h" -/* - * This quirk function disables memory decoding and releases memory resources - * of the device specified by kernel's boot parameter 'pci=resource_alignment='. - * It also rounds up size to specified alignment. - * Later on, the kernel will assign page-aligned memory resource back - * to the device. - */ -static void __devinit quirk_resource_alignment(struct pci_dev *dev) -{ - int i; - struct resource *r; - resource_size_t align, size; - u16 command; - - if (!pci_is_reassigndev(dev)) - return; - - if (dev->hdr_type == PCI_HEADER_TYPE_NORMAL && - (dev->class >> 8) == PCI_CLASS_BRIDGE_HOST) { - dev_warn(&dev->dev, - "Can't reassign resources to host bridge.\n"); - return; - } - - dev_info(&dev->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); - - align = pci_specified_resource_alignment(dev); - for (i=0; i < PCI_BRIDGE_RESOURCES; i++) { - r = &dev->resource[i]; - if (!(r->flags & IORESOURCE_MEM)) - continue; - size = resource_size(r); - if (size < align) { - size = align; - dev_info(&dev->dev, - "Rounding up size of resource #%d to %#llx.\n", - i, (unsigned long long)size); - } - r->end = size - 1; - r->start = 0; - } - /* Need to disable bridge's resource window, - * to enable the kernel to reassign new resource - * window later on. - */ - if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE && - (dev->class >> 8) == PCI_CLASS_BRIDGE_PCI) { - for (i = PCI_BRIDGE_RESOURCES; i < PCI_NUM_RESOURCES; i++) { - r = &dev->resource[i]; - if (!(r->flags & IORESOURCE_MEM)) - continue; - r->end = resource_size(r) - 1; - r->start = 0; - } - pci_disable_bridge_window(dev); - } -} -DECLARE_PCI_FIXUP_HEADER(PCI_ANY_ID, PCI_ANY_ID, quirk_resource_alignment); - /* * Decoding should be disabled for a PCI device during BAR sizing to avoid * conflict. But doing so may cause problems on host bridge and perhaps other diff --git a/drivers/pci/setup-res.c b/drivers/pci/setup-res.c index f968185aa19..eea85dafc76 100644 --- a/drivers/pci/setup-res.c +++ b/drivers/pci/setup-res.c @@ -114,7 +114,6 @@ int pci_claim_resource(struct pci_dev *dev, int resource) } EXPORT_SYMBOL(pci_claim_resource); -#ifdef CONFIG_PCI_QUIRKS void pci_disable_bridge_window(struct pci_dev *dev) { dev_info(&dev->dev, "disabling bridge mem windows\n"); @@ -127,9 +126,6 @@ void pci_disable_bridge_window(struct pci_dev *dev) pci_write_config_dword(dev, PCI_PREF_MEMORY_BASE, 0x0000fff0); pci_write_config_dword(dev, PCI_PREF_BASE_UPPER32, 0xffffffff); } -#endif /* CONFIG_PCI_QUIRKS */ - - static int __pci_assign_resource(struct pci_bus *bus, struct pci_dev *dev, int resno, resource_size_t size, resource_size_t align) -- cgit v1.2.3-70-g09d2 From 6748dcc269e52925993e0d68447858b41b88b4be Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Thu, 1 Mar 2012 00:06:33 +0100 Subject: PCI / PCIe: Introduce command line option to disable ARI There are PCIe devices on the market that report ARI support but then fail to initialize correctly when ARI is actually used. This leads to situations in which kernels 2.6.34 and newer fail to handle systems where the previous kernels worked without any apparent problems. Unfortunately, it is currently unknown how many such devices are there. For this reason, introduce a new kernel command line option, pci=noari, allowing users to disable PCIe ARI altogether if they see problems with PCIe device initialization. Signed-off-by: Rafael J. Wysocki Signed-off-by: Jesse Barnes --- Documentation/kernel-parameters.txt | 1 + drivers/pci/pci.c | 7 ++++++- 2 files changed, 7 insertions(+), 1 deletion(-) (limited to 'drivers/pci/pci.c') diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 7dc523e082a..3d153e5723b 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -2116,6 +2116,7 @@ bytes respectively. Such letter suffixes can also be entirely omitted. off: Turn realloc off on: Turn realloc on realloc same as realloc=on + noari do not use PCIe ARI. pcie_aspm= [PCIE] Forcibly enable or disable PCIe Active State Power Management. diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index b832f0fece9..81567441526 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -94,6 +94,9 @@ u8 pci_cache_line_size; */ unsigned int pcibios_max_latency = 255; +/* If set, the PCIe ARI capability will not be used. */ +static bool pcie_ari_disabled; + /** * pci_bus_max_busnr - returns maximum PCI bus number of given bus' children * @bus: pointer to PCI bus structure to search @@ -1955,7 +1958,7 @@ void pci_enable_ari(struct pci_dev *dev) u16 flags, ctrl; struct pci_dev *bridge; - if (!pci_is_pcie(dev) || dev->devfn) + if (pcie_ari_disabled || !pci_is_pcie(dev) || dev->devfn) return; pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ARI); @@ -3840,6 +3843,8 @@ static int __init pci_setup(char *str) pci_realloc_get_opt("on"); } else if (!strcmp(str, "nodomains")) { pci_no_domains(); + } else if (!strncmp(str, "noari", 5)) { + pcie_ari_disabled = true; } else if (!strncmp(str, "cbiosize=", 9)) { pci_cardbus_io_size = memparse(str + 9, &str); } else if (!strncmp(str, "cbmemsize=", 10)) { -- cgit v1.2.3-70-g09d2