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 362773247fb..7ffac27d5d4 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 v1.2.3-70-g09d2 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 7ffac27d5d4..f2725710593 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 v1.2.3-70-g09d2 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 f2725710593..f48f7550b4a 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 v1.2.3-70-g09d2 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 f48f7550b4a..79e56906c7f 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 v1.2.3-70-g09d2 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 79e56906c7f..944e45e4a84 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 v1.2.3-70-g09d2 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 944e45e4a84..d9f06fbfa0b 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 v1.2.3-70-g09d2