From 418e4da33f45fd7bdcce48778b149b780ff730bc Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Mon, 26 Jan 2009 21:43:08 +0100 Subject: PCI PM: Fix suspend error paths and testing facility breakage If one of device drivers refuses to suspend by returning error code from its ->suspend() callback, the devices that have already been suspended are resumed by executing their drivers' ->resume() callbacks. Some of these callbacks expect the device's configuration space to be restored if the device has been put into D3 before they are called. Unfortunately, this mechanism has been broken by recent changes moving the restoration of config spaces of some devices (most importantly, USB controllers and HDA Intel) into the resume callbacks executed with interrupts off. Obviously, these callbacks are not invoked in the suspend error path and, as a result, the system cannot be successfully brought back into the working state in case of a suspend error. The same thing happens in the hibernation error path right before putting the system into S4. Similarly, the suspend testing facility associated with the /sys/power/pm_test file is broken, because it uses the very same mechanism that is used in the suspend and hibernation error paths. Fix the breakage by making the PCI core restore the configuration spaces of PCI devices that haven't been restored already before pci_pm_resume() is called for those devices by the PM core. Signed-off-by: Rafael J. Wysocki Signed-off-by: Jesse Barnes --- drivers/pci/pci-driver.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) (limited to 'drivers') diff --git a/drivers/pci/pci-driver.c b/drivers/pci/pci-driver.c index 9de07b75b99..4884c4840b3 100644 --- a/drivers/pci/pci-driver.c +++ b/drivers/pci/pci-driver.c @@ -370,6 +370,7 @@ static int pci_legacy_suspend(struct device *dev, pm_message_t state) } pci_save_state(pci_dev); + pci_dev->state_saved = true; /* * This is for compatibility with existing code with legacy PM support. */ @@ -419,6 +420,7 @@ static int pci_legacy_resume(struct device *dev) static void pci_pm_default_resume_noirq(struct pci_dev *pci_dev) { pci_restore_standard_config(pci_dev); + pci_dev->state_saved = false; pci_fixup_device(pci_fixup_resume_early, pci_dev); } @@ -555,6 +557,13 @@ static int pci_pm_resume(struct device *dev) struct device_driver *drv = dev->driver; int error = 0; + /* + * This is necessary for the suspend error path in which resume is + * called without restoring the standard config registers of the device. + */ + if (pci_dev->state_saved) + pci_restore_standard_config(pci_dev); + if (pci_has_legacy_pm_support(pci_dev)) return pci_legacy_resume(dev); @@ -710,6 +719,13 @@ static int pci_pm_restore(struct device *dev) struct device_driver *drv = dev->driver; int error = 0; + /* + * This is necessary for the hibernation error path in which restore is + * called without restoring the standard config registers of the device. + */ + if (pci_dev->state_saved) + pci_restore_standard_config(pci_dev); + if (pci_has_legacy_pm_support(pci_dev)) return pci_legacy_resume(dev); -- cgit v1.2.3-70-g09d2 From 545ffd58adc86b8d33449dab44fe81b503a6f81b Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Thu, 22 Jan 2009 23:36:56 +0100 Subject: PCI PM: Fix hibernation breakage on EeePC 701 Hibernation breaks on EeePC 701 as a result of attempting to put one of its (driverless) devices into a low power state. Avoid that by not attepmting to power manage driverless devices during hibernation. Signed-off-by: Rafael J. Wysocki Reported-and-tested-by: Alan Jenkins Signed-off-by: Jesse Barnes --- drivers/pci/pci-driver.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) (limited to 'drivers') diff --git a/drivers/pci/pci-driver.c b/drivers/pci/pci-driver.c index 4884c4840b3..ab1d615425a 100644 --- a/drivers/pci/pci-driver.c +++ b/drivers/pci/pci-driver.c @@ -669,7 +669,10 @@ static int pci_pm_poweroff(struct device *dev) if (pci_has_legacy_pm_support(pci_dev)) return pci_legacy_suspend(dev, PMSG_HIBERNATE); - if (drv && drv->pm && drv->pm->poweroff) { + if (!drv || !drv->pm) + return 0; + + if (drv->pm->poweroff) { error = drv->pm->poweroff(dev); suspend_report_result(drv->pm->poweroff, error); } -- cgit v1.2.3-70-g09d2 From 48f67f54a53bb68619a63c3f38cf7f502ed74b1d Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Thu, 22 Jan 2009 23:38:31 +0100 Subject: PCI PM: Power up devices before restoring their state Devices that have MSI-X enabled before suspend to RAM or hibernation and that are in a low power state during resume will not be handled correctly by pci_restore_standard_config(). Namely, it first calls pci_restore_state() which calls pci_restore_msi_state(), which in turn executes __pci_restore_msix_state() that accesses the device's memory space to restore the contents of the MSI-X table. However, if the device is in a low power state at this point, it's memory space is not accessible. The easiest way to fix this potential problem is to make pci_restore_standard_config() call pci_restore_state() after it has put the device into the full power state, D0. Fortunately, all of this is done with interrupts off, so the change of ordering should not cause any trouble. Signed-off-by: Rafael J. Wysocki Signed-off-by: Jesse Barnes --- drivers/pci/pci.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'drivers') diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index 17bd9325a24..f0aa3d53383 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -1393,12 +1393,11 @@ int pci_restore_standard_config(struct pci_dev *dev) pci_power_t prev_state; int error; - pci_restore_state(dev); pci_update_current_state(dev, PCI_D0); prev_state = dev->current_state; if (prev_state == PCI_D0) - return 0; + goto Restore; error = pci_raw_set_power_state(dev, PCI_D0, false); if (error) @@ -1421,7 +1420,8 @@ int pci_restore_standard_config(struct pci_dev *dev) dev->current_state = PCI_D0; - return 0; + Restore: + return pci_restore_state(dev); } /** -- cgit v1.2.3-70-g09d2 From 476e7faefc43f106a90b5c96166c59b75de19d30 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Thu, 22 Jan 2009 23:39:57 +0100 Subject: PCI PM: Do not wait for buses in B2 or B3 during resume pci_restore_standard_config() adds extra delay for PCI buses in low power states (B2 or B3), but this is only correct for buses in B2, because the buses in B3 are reset when they are put back into B0. Thus we should wait for such buses to settle after the reset, but it's not a good idea to wait that long (1.1 s) with interrupts off. On the other hand, we have never waited for buses in B2 and B3 during resume and it seems reasonable to go back to this well tested behaviour. Signed-off-by: Rafael J. Wysocki Signed-off-by: Jesse Barnes --- drivers/pci/pci.c | 26 +++++++++++++------------- 1 file changed, 13 insertions(+), 13 deletions(-) (limited to 'drivers') diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index f0aa3d53383..48807556b47 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -1403,19 +1403,19 @@ int pci_restore_standard_config(struct pci_dev *dev) if (error) return error; - if (pci_is_bridge(dev)) { - if (prev_state > PCI_D1) - mdelay(PCI_PM_BUS_WAIT); - } else { - switch(prev_state) { - case PCI_D3cold: - case PCI_D3hot: - mdelay(pci_pm_d3_delay); - break; - case PCI_D2: - udelay(PCI_PM_D2_DELAY); - break; - } + /* + * This assumes that we won't get a bus in B2 or B3 from the BIOS, but + * we've made this assumption forever and it appears to be universally + * satisfied. + */ + switch(prev_state) { + case PCI_D3cold: + case PCI_D3hot: + mdelay(pci_pm_d3_delay); + break; + case PCI_D2: + udelay(PCI_PM_D2_DELAY); + break; } dev->current_state = PCI_D0; -- cgit v1.2.3-70-g09d2 From bffac3c593eba1f9da3efd0199e49ea6558a40ce Mon Sep 17 00:00:00 2001 From: Matthew Wilcox Date: Wed, 21 Jan 2009 19:19:19 -0500 Subject: PCI MSI: Fix undefined shift by 32 Add an msi_mask() function which returns the correct bitmask for the number of MSI interrupts you have. This fixes an undefined bug in msi_capability_init(). Signed-off-by: Matthew Wilcox Signed-off-by: Jesse Barnes --- drivers/pci/msi.c | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-) (limited to 'drivers') diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c index 896a15d70f5..44f15ff70c1 100644 --- a/drivers/pci/msi.c +++ b/drivers/pci/msi.c @@ -103,6 +103,16 @@ static void msix_set_enable(struct pci_dev *dev, int enable) } } +/* + * Essentially, this is ((1 << (1 << x)) - 1), but without the + * undefinedness of a << 32. + */ +static inline __attribute_const__ u32 msi_mask(unsigned x) +{ + static const u32 mask[] = { 1, 2, 4, 0xf, 0xff, 0xffff, 0xffffffff }; + return mask[x]; +} + static void msix_flush_writes(struct irq_desc *desc) { struct msi_desc *entry; @@ -407,8 +417,7 @@ static int msi_capability_init(struct pci_dev *dev) /* All MSIs are unmasked by default, Mask them all */ pci_read_config_dword(dev, base, &maskbits); - temp = (1 << multi_msi_capable(control)); - temp = ((temp - 1) & ~temp); + temp = msi_mask((control & PCI_MSI_FLAGS_QMASK) >> 1); maskbits |= temp; pci_write_config_dword(dev, base, maskbits); entry->msi_attrib.maskbits_mask = temp; -- cgit v1.2.3-70-g09d2 From bf4162bcf82ebc3258d6bc0ddd6453132abde72d Mon Sep 17 00:00:00 2001 From: "Darrick J. Wong" Date: Tue, 25 Nov 2008 13:51:44 -0800 Subject: PCI hotplug: fakephp: Allocate PCI resources before adding the device For PCI devices, pci_bus_assign_resources() must be called to set up the pci_device->resource array before pci_bus_add_devices() can be called, else attempts to load drivers results in BAR collision errors where there are none. This is not done in fakephp, so devices can be "unplugged" but scanning the parent bus won't bring the devices back due to resource unallocation. Move the pci_bus_add_device-calling logic into pci_rescan_bus and preface it with a call to pci_bus_assign_resources so that we only have to (re)allocate resources once per bus where a new device is found. Signed-off-by: Darrick J. Wong Acked-by: Alex Chiang Signed-off-by: Jesse Barnes --- drivers/pci/hotplug/fakephp.c | 42 ++++++++++++++++++++++++++---------------- 1 file changed, 26 insertions(+), 16 deletions(-) (limited to 'drivers') diff --git a/drivers/pci/hotplug/fakephp.c b/drivers/pci/hotplug/fakephp.c index b0e7de9e536..d8649e12729 100644 --- a/drivers/pci/hotplug/fakephp.c +++ b/drivers/pci/hotplug/fakephp.c @@ -195,13 +195,13 @@ static void remove_slot_worker(struct work_struct *work) * Tries hard not to re-enable already existing devices; * also handles scanning of subfunctions. */ -static void pci_rescan_slot(struct pci_dev *temp) +static int pci_rescan_slot(struct pci_dev *temp) { struct pci_bus *bus = temp->bus; struct pci_dev *dev; int func; - int retval; u8 hdr_type; + int count = 0; if (!pci_read_config_byte(temp, PCI_HEADER_TYPE, &hdr_type)) { temp->hdr_type = hdr_type & 0x7f; @@ -213,17 +213,12 @@ static void pci_rescan_slot(struct pci_dev *temp) dbg("New device on %s function %x:%x\n", bus->name, temp->devfn >> 3, temp->devfn & 7); - retval = pci_bus_add_device(dev); - if (retval) - dev_err(&dev->dev, "error adding " - "device, continuing.\n"); - else - add_slot(dev); + count++; } } /* multifunction device? */ if (!(hdr_type & 0x80)) - return; + return count; /* continue scanning for other functions */ for (func = 1, temp->devfn++; func < 8; func++, temp->devfn++) { @@ -239,16 +234,13 @@ static void pci_rescan_slot(struct pci_dev *temp) dbg("New device on %s function %x:%x\n", bus->name, temp->devfn >> 3, temp->devfn & 7); - retval = pci_bus_add_device(dev); - if (retval) - dev_err(&dev->dev, "error adding " - "device, continuing.\n"); - else - add_slot(dev); + count++; } } } } + + return count; } @@ -262,6 +254,8 @@ static void pci_rescan_bus(const struct pci_bus *bus) { unsigned int devfn; struct pci_dev *dev; + int retval; + int found = 0; dev = alloc_pci_dev(); if (!dev) return; @@ -270,7 +264,23 @@ static void pci_rescan_bus(const struct pci_bus *bus) dev->sysdata = bus->sysdata; for (devfn = 0; devfn < 0x100; devfn += 8) { dev->devfn = devfn; - pci_rescan_slot(dev); + found += pci_rescan_slot(dev); + } + + if (found) { + pci_bus_assign_resources(bus); + list_for_each_entry(dev, &bus->devices, bus_list) { + /* Skip already-added devices */ + if (dev->is_added) + continue; + retval = pci_bus_add_device(dev); + if (retval) + dev_err(&dev->dev, + "Error adding device, continuing\n"); + else + add_slot(dev); + } + pci_bus_add_devices(bus); } kfree(dev); } -- cgit v1.2.3-70-g09d2 From 71a082efc9fdc12068a3cee6cebb1330b00ebeee Mon Sep 17 00:00:00 2001 From: Matthew Garrett Date: Tue, 27 Jan 2009 01:03:35 +0000 Subject: PCI hotplug: Change link order of pciehp & acpiphp Some hardware exposes PCIE slots in such a way that they can be claimed by either the acpiphp or pciehp driver. pciehp is the preferred driver if the firmware allows the OS to claim control via the _OSC method so should be loaded first - if it fails to bind (either due to a missing _OSC method or the firmware refusing to hand off control) then we can fall back to acpiphp or a vendor-specific driver. This patch simply changes the link order to ensure that pciehp will be initialised before acpiphp if both are statically built into the kernel. Signed-off-by: Matthew Garrett Acked-by: Randy Dunlap Signed-off-by: Jesse Barnes --- drivers/pci/hotplug/Makefile | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) (limited to 'drivers') diff --git a/drivers/pci/hotplug/Makefile b/drivers/pci/hotplug/Makefile index e31fb91652c..2aa117c8cd8 100644 --- a/drivers/pci/hotplug/Makefile +++ b/drivers/pci/hotplug/Makefile @@ -5,11 +5,15 @@ obj-$(CONFIG_HOTPLUG_PCI) += pci_hotplug.o obj-$(CONFIG_HOTPLUG_PCI_COMPAQ) += cpqphp.o obj-$(CONFIG_HOTPLUG_PCI_IBM) += ibmphp.o + +# pciehp should be linked before acpiphp in order to allow the native driver +# to attempt to bind first. We can then fall back to generic support. + +obj-$(CONFIG_HOTPLUG_PCI_PCIE) += pciehp.o obj-$(CONFIG_HOTPLUG_PCI_ACPI) += acpiphp.o obj-$(CONFIG_HOTPLUG_PCI_ACPI_IBM) += acpiphp_ibm.o obj-$(CONFIG_HOTPLUG_PCI_CPCI_ZT5550) += cpcihp_zt5550.o obj-$(CONFIG_HOTPLUG_PCI_CPCI_GENERIC) += cpcihp_generic.o -obj-$(CONFIG_HOTPLUG_PCI_PCIE) += pciehp.o obj-$(CONFIG_HOTPLUG_PCI_SHPC) += shpchp.o obj-$(CONFIG_HOTPLUG_PCI_RPA) += rpaphp.o obj-$(CONFIG_HOTPLUG_PCI_RPA_DLPAR) += rpadlpar_io.o -- cgit v1.2.3-70-g09d2