From 67b5db6502ddd27d65dea43bf036abbd82d0dfc9 Mon Sep 17 00:00:00 2001 From: Hidetoshi Seto Date: Mon, 20 Apr 2009 10:54:59 +0900 Subject: PCI MSI: Define PCI_MSI_MASK_32/64 Impact: cleanup, improve readability Define PCI_MSI_MASK_32/64 for 32/64bit devices, instead of using implicit offset (-4), "PCI_MSI_MASK_BIT - 4" and "PCI_MSI_MASK_BIT". Signed-off-by: Hidetoshi Seto Reviewed-by: Matthew Wilcox Signed-off-by: Jesse Barnes --- drivers/pci/msi.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/pci/msi.c') diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c index 362773247fbf..7ffac27d5d4a 100644 --- a/drivers/pci/msi.c +++ b/drivers/pci/msi.c @@ -381,7 +381,7 @@ static int msi_capability_init(struct pci_dev *dev, int nvec) entry->msi_attrib.default_irq = dev->irq; /* Save IOAPIC IRQ */ entry->msi_attrib.pos = pos; - entry->mask_pos = msi_mask_bits_reg(pos, entry->msi_attrib.is_64); + entry->mask_pos = msi_mask_reg(pos, entry->msi_attrib.is_64); /* All MSIs are unmasked by default, Mask them all */ if (entry->msi_attrib.maskbit) pci_read_config_dword(dev, entry->mask_pos, &entry->masked); -- cgit v1.2.3 From 57fbf52c86addd8e25d1975fac0d59d982d1f6ec Mon Sep 17 00:00:00 2001 From: "Michael S. Tsirkin" Date: Thu, 7 May 2009 11:28:41 +0300 Subject: PCI MSI: let drivers retry when not enough vectors pci_enable_msix currently returns -EINVAL if you ask for more vectors than supported by the device, which would typically cause fallback to regular interrupts. It's better to return the table size, making the driver retry MSI-X with less vectors. Reviewed-by: Matthew Wilcox Signed-off-by: Michael S. Tsirkin Signed-off-by: Jesse Barnes --- drivers/pci/msi.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'drivers/pci/msi.c') diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c index 7ffac27d5d4a..f2725710593a 100644 --- a/drivers/pci/msi.c +++ b/drivers/pci/msi.c @@ -691,8 +691,8 @@ int pci_msix_table_size(struct pci_dev *dev) * indicates the successful configuration of MSI-X capability structure * with new allocated MSI-X irqs. A return of < 0 indicates a failure. * Or a return of > 0 indicates that driver request is exceeding the number - * of irqs available. Driver should use the returned value to re-send - * its request. + * of irqs or MSI-X vectors available. Driver should use the returned value to + * re-send its request. **/ int pci_enable_msix(struct pci_dev* dev, struct msix_entry *entries, int nvec) { @@ -708,7 +708,7 @@ int pci_enable_msix(struct pci_dev* dev, struct msix_entry *entries, int nvec) nr_entries = pci_msix_table_size(dev); if (nvec > nr_entries) - return -EINVAL; + return nr_entries; /* Check for any invalid entries */ for (i = 0; i < nvec; i++) { -- cgit v1.2.3 From ab7de999a2c771482698efa6fe7c7b7fcb1d482a Mon Sep 17 00:00:00 2001 From: Kenji Kaneshige Date: Tue, 16 Jun 2009 16:25:40 +0900 Subject: PCI: remove invalid comment of msi_mask_irq() Remove invalid comment of msi_mask_irq(). Reviewed-by: Matthew Wilcox Signed-off-by: Kenji Kaneshige Signed-off-by: Jesse Barnes --- drivers/pci/msi.c | 3 --- 1 file changed, 3 deletions(-) (limited to 'drivers/pci/msi.c') diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c index f2725710593a..f48f7550b4a7 100644 --- a/drivers/pci/msi.c +++ b/drivers/pci/msi.c @@ -131,9 +131,6 @@ static inline __attribute_const__ u32 msi_enabled_mask(u16 control) * mask all MSI interrupts by clearing the MSI enable bit does not work * reliably as devices without an INTx disable bit will then generate a * level IRQ which will never be cleared. - * - * Returns 1 if it succeeded in masking the interrupt and 0 if the device - * doesn't support MSI masking. */ static void msi_mask_irq(struct msi_desc *desc, u32 mask, u32 flag) { -- cgit v1.2.3 From 110828c9cdce6e8ec68479ced4ca0bdc1135bb91 Mon Sep 17 00:00:00 2001 From: Matthew Wilcox Date: Tue, 16 Jun 2009 06:31:45 -0600 Subject: PCI: remove redundant __msi_set_enable() We have the 'pos' of the MSI capability at all locations which call msi_set_enable(), so pass it to msi_set_enable() instead of making it find the capability every time. Reviewed-by: Kenji Kaneshige Signed-off-by: Matthew Wilcox Signed-off-by: Jesse Barnes --- drivers/pci/msi.c | 38 ++++++++++++++++++-------------------- 1 file changed, 18 insertions(+), 20 deletions(-) (limited to 'drivers/pci/msi.c') diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c index f48f7550b4a7..79e56906c7f1 100644 --- a/drivers/pci/msi.c +++ b/drivers/pci/msi.c @@ -75,22 +75,17 @@ void arch_teardown_msi_irqs(struct pci_dev *dev) } #endif -static void __msi_set_enable(struct pci_dev *dev, int pos, int enable) +static void msi_set_enable(struct pci_dev *dev, int pos, int enable) { u16 control; - if (pos) { - pci_read_config_word(dev, pos + PCI_MSI_FLAGS, &control); - control &= ~PCI_MSI_FLAGS_ENABLE; - if (enable) - control |= PCI_MSI_FLAGS_ENABLE; - pci_write_config_word(dev, pos + PCI_MSI_FLAGS, control); - } -} + BUG_ON(!pos); -static void msi_set_enable(struct pci_dev *dev, int enable) -{ - __msi_set_enable(dev, pci_find_capability(dev, PCI_CAP_ID_MSI), enable); + pci_read_config_word(dev, pos + PCI_MSI_FLAGS, &control); + control &= ~PCI_MSI_FLAGS_ENABLE; + if (enable) + control |= PCI_MSI_FLAGS_ENABLE; + pci_write_config_word(dev, pos + PCI_MSI_FLAGS, control); } static void msix_set_enable(struct pci_dev *dev, int enable) @@ -300,7 +295,7 @@ static void __pci_restore_msi_state(struct pci_dev *dev) pos = entry->msi_attrib.pos; pci_intx_for_msi(dev, 0); - msi_set_enable(dev, 0); + msi_set_enable(dev, pos, 0); write_msi_msg(dev->irq, &entry->msg); pci_read_config_word(dev, pos + PCI_MSI_FLAGS, &control); @@ -362,9 +357,9 @@ static int msi_capability_init(struct pci_dev *dev, int nvec) u16 control; unsigned mask; - msi_set_enable(dev, 0); /* Ensure msi is disabled as I set it up */ - pos = pci_find_capability(dev, PCI_CAP_ID_MSI); + msi_set_enable(dev, pos, 0); /* Disable MSI during set up */ + pci_read_config_word(dev, msi_control_reg(pos), &control); /* MSI Entry Initialization */ entry = alloc_msi_entry(dev); @@ -396,7 +391,7 @@ static int msi_capability_init(struct pci_dev *dev, int nvec) /* Set MSI enabled bits */ pci_intx_for_msi(dev, 0); - msi_set_enable(dev, 1); + msi_set_enable(dev, pos, 1); dev->msi_enabled = 1; dev->irq = entry->irq; @@ -593,17 +588,20 @@ void pci_msi_shutdown(struct pci_dev *dev) struct msi_desc *desc; u32 mask; u16 ctrl; + unsigned pos; if (!pci_msi_enable || !dev || !dev->msi_enabled) return; - msi_set_enable(dev, 0); + BUG_ON(list_empty(&dev->msi_list)); + desc = list_first_entry(&dev->msi_list, struct msi_desc, list); + pos = desc->msi_attrib.pos; + + msi_set_enable(dev, pos, 0); pci_intx_for_msi(dev, 1); dev->msi_enabled = 0; - BUG_ON(list_empty(&dev->msi_list)); - desc = list_first_entry(&dev->msi_list, struct msi_desc, list); - pci_read_config_word(dev, desc->msi_attrib.pos + PCI_MSI_FLAGS, &ctrl); + pci_read_config_word(dev, pos + PCI_MSI_FLAGS, &ctrl); mask = msi_capable_mask(ctrl); msi_mask_irq(desc, mask, ~mask); -- cgit v1.2.3 From f598282f5145036312d90875d0ed5c14b49fd8a7 Mon Sep 17 00:00:00 2001 From: Matthew Wilcox Date: Thu, 18 Jun 2009 19:15:59 -0700 Subject: PCI: Fix the NIU MSI-X problem in a better way The previous MSI-X fix (8d181018532dd709ec1f789e374cda92d7b01ce1) had three bugs. First, it didn't move the write that disabled the vector. This led to writing garbage to the MSI-X vector (spotted by Michael Ellerman). It didn't fix the PCI resume case, and it had a race window where the device could generate an interrupt before the MSI-X registers were programmed (leading to a DMA to random addresses). Fortunately, the MSI-X capability has a bit to mask all the vectors. By setting this bit instead of clearing the enable bit, we can ensure the device will not generate spurious interrupts. Since the capability is now enabled, the NIU device will not have a problem with the reads and writes to the MSI-X registers being in the original order in the code. Signed-off-by: Matthew Wilcox Reviewed-by: Hidetoshi Seto Signed-off-by: Jesse Barnes --- drivers/pci/msi.c | 46 ++++++++++++++++++++++++++++------------------ 1 file changed, 28 insertions(+), 18 deletions(-) (limited to 'drivers/pci/msi.c') diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c index 79e56906c7f1..944e45e4a84f 100644 --- a/drivers/pci/msi.c +++ b/drivers/pci/msi.c @@ -313,22 +313,22 @@ static void __pci_restore_msix_state(struct pci_dev *dev) if (!dev->msix_enabled) return; + BUG_ON(list_empty(&dev->msi_list)); + entry = list_entry(dev->msi_list.next, struct msi_desc, list); + pos = entry->msi_attrib.pos; + pci_read_config_word(dev, pos + PCI_MSIX_FLAGS, &control); /* route the table */ pci_intx_for_msi(dev, 0); - msix_set_enable(dev, 0); + control |= PCI_MSIX_FLAGS_ENABLE | PCI_MSIX_FLAGS_MASKALL; + pci_write_config_word(dev, pos + PCI_MSIX_FLAGS, control); list_for_each_entry(entry, &dev->msi_list, list) { write_msi_msg(entry->irq, &entry->msg); msix_mask_irq(entry, entry->masked); } - BUG_ON(list_empty(&dev->msi_list)); - entry = list_entry(dev->msi_list.next, struct msi_desc, list); - pos = entry->msi_attrib.pos; - pci_read_config_word(dev, pos + PCI_MSIX_FLAGS, &control); control &= ~PCI_MSIX_FLAGS_MASKALL; - control |= PCI_MSIX_FLAGS_ENABLE; pci_write_config_word(dev, pos + PCI_MSIX_FLAGS, control); } @@ -419,11 +419,14 @@ static int msix_capability_init(struct pci_dev *dev, u8 bir; void __iomem *base; - msix_set_enable(dev, 0);/* Ensure msix is disabled as I set it up */ - pos = pci_find_capability(dev, PCI_CAP_ID_MSIX); + pci_read_config_word(dev, pos + PCI_MSIX_FLAGS, &control); + + /* Ensure MSI-X is disabled while it is set up */ + control &= ~PCI_MSIX_FLAGS_ENABLE; + pci_write_config_word(dev, pos + PCI_MSIX_FLAGS, control); + /* Request & Map MSI-X table region */ - pci_read_config_word(dev, msi_control_reg(pos), &control); nr_entries = multi_msix_capable(control); pci_read_config_dword(dev, msix_table_offset_reg(pos), &table_offset); @@ -434,7 +437,6 @@ static int msix_capability_init(struct pci_dev *dev, if (base == NULL) return -ENOMEM; - /* MSI-X Table Initialization */ for (i = 0; i < nvec; i++) { entry = alloc_msi_entry(dev); if (!entry) @@ -447,7 +449,6 @@ static int msix_capability_init(struct pci_dev *dev, entry->msi_attrib.default_irq = dev->irq; entry->msi_attrib.pos = pos; entry->mask_base = base; - msix_mask_irq(entry, 1); list_add_tail(&entry->list, &dev->msi_list); } @@ -472,22 +473,31 @@ static int msix_capability_init(struct pci_dev *dev, return ret; } + /* + * Some devices require MSI-X to be enabled before we can touch the + * MSI-X registers. We need to mask all the vectors to prevent + * interrupts coming in before they're fully set up. + */ + control |= PCI_MSIX_FLAGS_MASKALL | PCI_MSIX_FLAGS_ENABLE; + pci_write_config_word(dev, pos + PCI_MSIX_FLAGS, control); + i = 0; list_for_each_entry(entry, &dev->msi_list, list) { entries[i].vector = entry->irq; set_irq_msi(entry->irq, entry); + j = entries[i].entry; + entry->masked = readl(base + j * PCI_MSIX_ENTRY_SIZE + + PCI_MSIX_ENTRY_VECTOR_CTRL_OFFSET); + msix_mask_irq(entry, 1); i++; } - /* Set MSI-X enabled bits */ + + /* Set MSI-X enabled bits and unmask the function */ pci_intx_for_msi(dev, 0); - msix_set_enable(dev, 1); dev->msix_enabled = 1; - list_for_each_entry(entry, &dev->msi_list, list) { - int vector = entry->msi_attrib.entry_nr; - entry->masked = readl(base + vector * PCI_MSIX_ENTRY_SIZE + - PCI_MSIX_ENTRY_VECTOR_CTRL_OFFSET); - } + control &= ~PCI_MSIX_FLAGS_MASKALL; + pci_write_config_word(dev, pos + PCI_MSIX_FLAGS, control); return 0; } -- cgit v1.2.3 From 2af5066f664cb011cf17d2e4414491fe24597e07 Mon Sep 17 00:00:00 2001 From: Hidetoshi Seto Date: Thu, 18 Jun 2009 19:20:26 -0700 Subject: PCI: make msi_free_irqs() to use msix_mask_irq() instead of open coded write Use msix_mask_irq() instead of direct use of writel, so as not to clear preserved bits in the Vector Control register [31:1]. Signed-off-by: Hidetoshi Seto Signed-off-by: Jesse Barnes --- drivers/pci/msi.c | 5 +---- 1 file changed, 1 insertion(+), 4 deletions(-) (limited to 'drivers/pci/msi.c') diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c index 944e45e4a84f..d9f06fbfa0bf 100644 --- a/drivers/pci/msi.c +++ b/drivers/pci/msi.c @@ -653,10 +653,7 @@ static int msi_free_irqs(struct pci_dev* dev) list_for_each_entry_safe(entry, tmp, &dev->msi_list, list) { if (entry->msi_attrib.is_msix) { - writel(1, entry->mask_base + entry->msi_attrib.entry_nr - * PCI_MSIX_ENTRY_SIZE - + PCI_MSIX_ENTRY_VECTOR_CTRL_OFFSET); - + msix_mask_irq(entry, 1); if (list_is_last(&entry->list, &dev->msi_list)) iounmap(entry->mask_base); } -- cgit v1.2.3 From 0d07348931daef854aca8c834a89f1a99ba4ff2b Mon Sep 17 00:00:00 2001 From: Hidetoshi Seto Date: Wed, 24 Jun 2009 12:08:27 +0900 Subject: PCI MSI: Return if alloc_msi_entry for MSI-X failed In current code it continues setup even if alloc_msi_entry() for MSI-X is failed due to lack of memory. It means arch_setup_msi_irqs() might be called with msi_desc entries less than its argument nvec. At least x86's arch_setup_msi_irqs() uses list_for_each_entry() for dev->msi_list that suspected to have entries same numbers as nvec, and it doesn't check the number of allocated vectors and passed arg nvec. Therefore it will result in success of pci_enable_msix(), with less vectors allocated than requested. This patch fixes the error route to return -ENOMEM, instead of continuing the setup (proposed by Matthew Wilcox). Note that there is no iounmap in msi_free_irqs() if no msi_disc is allocated. Reviewed-by: Matthew Wilcox Signed-off-by: Hidetoshi Seto Signed-off-by: Jesse Barnes --- drivers/pci/msi.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) (limited to 'drivers/pci/msi.c') diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c index d9f06fbfa0bf..628c14150d49 100644 --- a/drivers/pci/msi.c +++ b/drivers/pci/msi.c @@ -439,8 +439,14 @@ static int msix_capability_init(struct pci_dev *dev, for (i = 0; i < nvec; i++) { entry = alloc_msi_entry(dev); - if (!entry) - break; + if (!entry) { + if (!i) + iounmap(base); + else + msi_free_irqs(dev); + /* No enough memory. Don't try again */ + return -ENOMEM; + } j = entries[i].entry; entry->msi_attrib.is_msix = 1; -- cgit v1.2.3 From 2c21fd4b333e4c780a46edcd6d1e85bfc6cdf371 Mon Sep 17 00:00:00 2001 From: Hidetoshi Seto Date: Tue, 23 Jun 2009 17:40:04 +0900 Subject: PCI MSI: shorten PCI_MSIX_ENTRY_* symbol names These names are too long! Drop _OFFSET to save some bytes/lines. Reviewed-by: Matthew Wilcox Signed-off-by: Hidetoshi Seto Signed-off-by: Jesse Barnes --- drivers/pci/msi.c | 18 ++++++++---------- drivers/pci/msi.h | 10 +++++----- 2 files changed, 13 insertions(+), 15 deletions(-) (limited to 'drivers/pci/msi.c') diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c index 628c14150d49..a088fc6f5838 100644 --- a/drivers/pci/msi.c +++ b/drivers/pci/msi.c @@ -151,7 +151,7 @@ static void msix_mask_irq(struct msi_desc *desc, u32 flag) { u32 mask_bits = desc->masked; unsigned offset = desc->msi_attrib.entry_nr * PCI_MSIX_ENTRY_SIZE + - PCI_MSIX_ENTRY_VECTOR_CTRL_OFFSET; + PCI_MSIX_ENTRY_VECTOR_CTRL; mask_bits &= ~1; mask_bits |= flag; writel(mask_bits, desc->mask_base + offset); @@ -188,9 +188,9 @@ void read_msi_msg_desc(struct irq_desc *desc, struct msi_msg *msg) void __iomem *base = entry->mask_base + entry->msi_attrib.entry_nr * PCI_MSIX_ENTRY_SIZE; - msg->address_lo = readl(base + PCI_MSIX_ENTRY_LOWER_ADDR_OFFSET); - msg->address_hi = readl(base + PCI_MSIX_ENTRY_UPPER_ADDR_OFFSET); - msg->data = readl(base + PCI_MSIX_ENTRY_DATA_OFFSET); + msg->address_lo = readl(base + PCI_MSIX_ENTRY_LOWER_ADDR); + msg->address_hi = readl(base + PCI_MSIX_ENTRY_UPPER_ADDR); + msg->data = readl(base + PCI_MSIX_ENTRY_DATA); } else { struct pci_dev *dev = entry->dev; int pos = entry->msi_attrib.pos; @@ -225,11 +225,9 @@ void write_msi_msg_desc(struct irq_desc *desc, struct msi_msg *msg) base = entry->mask_base + entry->msi_attrib.entry_nr * PCI_MSIX_ENTRY_SIZE; - writel(msg->address_lo, - base + PCI_MSIX_ENTRY_LOWER_ADDR_OFFSET); - writel(msg->address_hi, - base + PCI_MSIX_ENTRY_UPPER_ADDR_OFFSET); - writel(msg->data, base + PCI_MSIX_ENTRY_DATA_OFFSET); + writel(msg->address_lo, base + PCI_MSIX_ENTRY_LOWER_ADDR); + writel(msg->address_hi, base + PCI_MSIX_ENTRY_UPPER_ADDR); + writel(msg->data, base + PCI_MSIX_ENTRY_DATA); } else { struct pci_dev *dev = entry->dev; int pos = entry->msi_attrib.pos; @@ -493,7 +491,7 @@ static int msix_capability_init(struct pci_dev *dev, set_irq_msi(entry->irq, entry); j = entries[i].entry; entry->masked = readl(base + j * PCI_MSIX_ENTRY_SIZE + - PCI_MSIX_ENTRY_VECTOR_CTRL_OFFSET); + PCI_MSIX_ENTRY_VECTOR_CTRL); msix_mask_irq(entry, 1); i++; } diff --git a/drivers/pci/msi.h b/drivers/pci/msi.h index a0662842550b..de27c1cb5a2b 100644 --- a/drivers/pci/msi.h +++ b/drivers/pci/msi.h @@ -6,11 +6,11 @@ #ifndef MSI_H #define MSI_H -#define PCI_MSIX_ENTRY_SIZE 16 -#define PCI_MSIX_ENTRY_LOWER_ADDR_OFFSET 0 -#define PCI_MSIX_ENTRY_UPPER_ADDR_OFFSET 4 -#define PCI_MSIX_ENTRY_DATA_OFFSET 8 -#define PCI_MSIX_ENTRY_VECTOR_CTRL_OFFSET 12 +#define PCI_MSIX_ENTRY_SIZE 16 +#define PCI_MSIX_ENTRY_LOWER_ADDR 0 +#define PCI_MSIX_ENTRY_UPPER_ADDR 4 +#define PCI_MSIX_ENTRY_DATA 8 +#define PCI_MSIX_ENTRY_VECTOR_CTRL 12 #define msi_control_reg(base) (base + PCI_MSI_FLAGS) #define msi_lower_address_reg(base) (base + PCI_MSI_ADDRESS_LO) -- cgit v1.2.3 From 7ba1930db02fc3118165338ef4e562869f575583 Mon Sep 17 00:00:00 2001 From: Hidetoshi Seto Date: Tue, 23 Jun 2009 17:39:27 +0900 Subject: PCI MSI: Unmask MSI if setup failed The initial state of mask register of MSI is unmasked. We set it masked before calling arch_setup_msi_irqs(). If arch_setup_msi_irq() fails, it is better to restore the state of the mask register. Reviewed-by: Matthew Wilcox Signed-off-by: Hidetoshi Seto Signed-off-by: Jesse Barnes --- drivers/pci/msi.c | 1 + 1 file changed, 1 insertion(+) (limited to 'drivers/pci/msi.c') diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c index a088fc6f5838..9ab4fe8f20af 100644 --- a/drivers/pci/msi.c +++ b/drivers/pci/msi.c @@ -383,6 +383,7 @@ static int msi_capability_init(struct pci_dev *dev, int nvec) /* Configure MSI capability structure */ ret = arch_setup_msi_irqs(dev, nvec, PCI_CAP_ID_MSI); if (ret) { + msi_mask_irq(entry, mask, ~mask); msi_free_irqs(dev); return ret; } -- cgit v1.2.3 From 12abb8ba8444f7c9b355bbdd44a6d0839f7a41b6 Mon Sep 17 00:00:00 2001 From: Hidetoshi Seto Date: Wed, 24 Jun 2009 12:08:09 +0900 Subject: PCI MSI: Fix restoration of MSI/MSI-X mask states in suspend/resume There are 2 problems on mask states in suspend/resume. [1]: It is better to restore the mask states of MSI/MSI-X to initial states (MSI is unmasked, MSI-X is masked) when we release the device. The pci_msi_shutdown() does the restoration of mask states for MSI, while the msi_free_irqs() does it for MSI-X. In other words, in the "disable" path both of MSI and MSI-X are handled, but in the "shutdown" path only MSI is handled. MSI: pci_disable_msi() => pci_msi_shutdown() [ mask states for MSI restored ] => msi_set_enable(dev, pos, 0); => msi_free_irqs() MSI-X: pci_disable_msix() => pci_msix_shutdown() => msix_set_enable(dev, 0); => msix_free_all_irqs => msi_free_irqs() [ mask states for MSI-X restored ] This patch moves the masking for MSI-X from msi_free_irqs() to pci_msix_shutdown(). This change has some positive side effects: - It prevents OS from touching mask states before reading preserved bits in the register, which can be happen if msi_free_irqs() is called from error path in msix_capability_init(). - It also prevents touching the register after turning off MSI-X in "disable" path, which can be a problem on some devices. [2]: We have cache of the mask state in msi_desc, which is automatically updated when msi/msix_mask_irq() is called. This cached states are used for the resume. But since what need to be restored in the resume is the states before the shutdown on the suspend, calling msi/msix_mask_irq() from pci_msi/msix_shutdown() is not appropriate. This patch introduces __msi/msix_mask_irq() that do mask as same as msi/msix_mask_irq() but does not update cached state, for use in pci_msi/msix_shutdown(). [updated: get rid of msi/msix_mask_irq_nocache() (proposed by Matthew Wilcox)] Reviewed-by: Matthew Wilcox Signed-off-by: Hidetoshi Seto Signed-off-by: Jesse Barnes --- drivers/pci/msi.c | 35 ++++++++++++++++++++++++++++------- 1 file changed, 28 insertions(+), 7 deletions(-) (limited to 'drivers/pci/msi.c') diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c index 9ab4fe8f20af..d986afb7032b 100644 --- a/drivers/pci/msi.c +++ b/drivers/pci/msi.c @@ -127,17 +127,23 @@ static inline __attribute_const__ u32 msi_enabled_mask(u16 control) * reliably as devices without an INTx disable bit will then generate a * level IRQ which will never be cleared. */ -static void msi_mask_irq(struct msi_desc *desc, u32 mask, u32 flag) +static u32 __msi_mask_irq(struct msi_desc *desc, u32 mask, u32 flag) { u32 mask_bits = desc->masked; if (!desc->msi_attrib.maskbit) - return; + return 0; mask_bits &= ~mask; mask_bits |= flag; pci_write_config_dword(desc->dev, desc->mask_pos, mask_bits); - desc->masked = mask_bits; + + return mask_bits; +} + +static void msi_mask_irq(struct msi_desc *desc, u32 mask, u32 flag) +{ + desc->masked = __msi_mask_irq(desc, mask, flag); } /* @@ -147,7 +153,7 @@ static void msi_mask_irq(struct msi_desc *desc, u32 mask, u32 flag) * file. This saves a few milliseconds when initialising devices with lots * of MSI-X interrupts. */ -static void msix_mask_irq(struct msi_desc *desc, u32 flag) +static u32 __msix_mask_irq(struct msi_desc *desc, u32 flag) { u32 mask_bits = desc->masked; unsigned offset = desc->msi_attrib.entry_nr * PCI_MSIX_ENTRY_SIZE + @@ -155,7 +161,13 @@ static void msix_mask_irq(struct msi_desc *desc, u32 flag) mask_bits &= ~1; mask_bits |= flag; writel(mask_bits, desc->mask_base + offset); - desc->masked = mask_bits; + + return mask_bits; +} + +static void msix_mask_irq(struct msi_desc *desc, u32 flag) +{ + desc->masked = __msix_mask_irq(desc, flag); } static void msi_set_mask_bit(unsigned irq, u32 flag) @@ -616,9 +628,11 @@ void pci_msi_shutdown(struct pci_dev *dev) pci_intx_for_msi(dev, 1); dev->msi_enabled = 0; + /* Return the device with MSI unmasked as initial states */ pci_read_config_word(dev, pos + PCI_MSI_FLAGS, &ctrl); mask = msi_capable_mask(ctrl); - msi_mask_irq(desc, mask, ~mask); + /* Keep cached state to be restored */ + __msi_mask_irq(desc, mask, ~mask); /* Restore dev->irq to its default pin-assertion irq */ dev->irq = desc->msi_attrib.default_irq; @@ -658,7 +672,6 @@ static int msi_free_irqs(struct pci_dev* dev) list_for_each_entry_safe(entry, tmp, &dev->msi_list, list) { if (entry->msi_attrib.is_msix) { - msix_mask_irq(entry, 1); if (list_is_last(&entry->list, &dev->msi_list)) iounmap(entry->mask_base); } @@ -746,9 +759,17 @@ static void msix_free_all_irqs(struct pci_dev *dev) void pci_msix_shutdown(struct pci_dev* dev) { + struct msi_desc *entry; + if (!pci_msi_enable || !dev || !dev->msix_enabled) return; + /* Return the device with MSI-X masked as initial states */ + list_for_each_entry(entry, &dev->msi_list, list) { + /* Keep cached states to be restored */ + __msix_mask_irq(entry, 1); + } + msix_set_enable(dev, 0); pci_intx_for_msi(dev, 1); dev->msix_enabled = 0; -- cgit v1.2.3