From 24d27553390c69d11cdbd930d635193956fc295f Mon Sep 17 00:00:00 2001 From: Matthew Wilcox Date: Tue, 17 Mar 2009 08:54:06 -0400 Subject: PCI MSI: Replace 'type' with 'is_msix' By changing from a 5-bit field to a 1-bit field, we free up some bits that can be used by a later patch. Also rearrange the fields for better packing on 64-bit platforms (reducing the size of msi_desc from 72 bytes to 64 bytes). Signed-off-by: Matthew Wilcox Signed-off-by: Jesse Barnes --- include/linux/msi.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'include/linux/msi.h') diff --git a/include/linux/msi.h b/include/linux/msi.h index d2b8a1e8ca11..9c5ce214fbf4 100644 --- a/include/linux/msi.h +++ b/include/linux/msi.h @@ -20,13 +20,13 @@ extern void write_msi_msg(unsigned int irq, struct msi_msg *msg); struct msi_desc { struct { - __u8 type : 5; /* {0: unused, 5h:MSI, 11h:MSI-X} */ + __u8 is_msix : 1; __u8 maskbit : 1; /* mask-pending bit supported ? */ __u8 masked : 1; __u8 is_64 : 1; /* Address size: 0=32bit 1=64bit */ __u8 pos; /* Location of the msi capability */ - __u32 maskbits_mask; /* mask bits mask */ __u16 entry_nr; /* specific enabled entry */ + __u32 maskbits_mask; /* mask bits mask */ unsigned default_irq; /* default pre-assigned irq */ }msi_attrib; -- cgit v1.2.3 From 264d9caaa1c574c0274b019a810abfe957391005 Mon Sep 17 00:00:00 2001 From: Matthew Wilcox Date: Tue, 17 Mar 2009 08:54:08 -0400 Subject: PCI MSI: Use mask_pos instead of mask_base when appropriate MSI interrupts have a mask_pos where MSI-X have a mask_base. Use a transparent union to get rid of some ugly casts. Signed-off-by: Matthew Wilcox Signed-off-by: Jesse Barnes --- drivers/pci/msi.c | 5 ++--- include/linux/msi.h | 5 ++++- 2 files changed, 6 insertions(+), 4 deletions(-) (limited to 'include/linux/msi.h') diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c index a658c0f34e16..fcde04df6dfe 100644 --- a/drivers/pci/msi.c +++ b/drivers/pci/msi.c @@ -145,7 +145,7 @@ static int msi_set_mask_bits(struct irq_desc *desc, u32 mask, u32 flag) if (!entry->msi_attrib.maskbit) return 0; - pos = (long)entry->mask_base; + pos = entry->mask_pos; pci_read_config_dword(entry->dev, pos, &mask_bits); mask_bits &= ~mask; mask_bits |= flag & mask; @@ -363,8 +363,7 @@ static int msi_capability_init(struct pci_dev *dev) unsigned int base, maskbits, temp; base = msi_mask_bits_reg(pos, entry->msi_attrib.is_64); - entry->mask_base = (void __iomem *)(long)base; - + entry->mask_pos = base; /* All MSIs are unmasked by default, Mask them all */ pci_read_config_dword(dev, base, &maskbits); temp = msi_mask((control & PCI_MSI_FLAGS_QMASK) >> 1); diff --git a/include/linux/msi.h b/include/linux/msi.h index 9c5ce214fbf4..5025ca4d91e4 100644 --- a/include/linux/msi.h +++ b/include/linux/msi.h @@ -33,7 +33,10 @@ struct msi_desc { unsigned int irq; struct list_head list; - void __iomem *mask_base; + union { + void __iomem *mask_base; + u8 mask_pos; + }; struct pci_dev *dev; /* Last set MSI message */ -- cgit v1.2.3 From f2440d9acbe866b917b16cc0f927366341ce9215 Mon Sep 17 00:00:00 2001 From: Matthew Wilcox Date: Tue, 17 Mar 2009 08:54:09 -0400 Subject: PCI MSI: Refactor interrupt masking code Since most of the callers already know whether they have an MSI or an MSI-X capability, split msi_set_mask_bits() into msi_mask_irq() and msix_mask_irq(). The only callers which don't (mask_msi_irq() and unmask_msi_irq()) can share code in msi_set_mask_bit(). This then becomes the only caller of msix_flush_writes(), so we can inline it. The flushing read can be to any address that belongs to the device, so we can eliminate the calculation too. We can also get rid of maskbits_mask from struct msi_desc and simply recalculate it on the rare occasion that we need it. The single-bit 'masked' element is replaced by a copy of the 32-bit 'masked' register, so this patch does not affect the size of msi_desc. Signed-off-by: Matthew Wilcox Signed-off-by: Jesse Barnes --- drivers/pci/msi.c | 155 +++++++++++++++++++++++++--------------------------- include/linux/msi.h | 5 +- 2 files changed, 77 insertions(+), 83 deletions(-) (limited to 'include/linux/msi.h') diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c index fcde04df6dfe..adcc78242571 100644 --- a/drivers/pci/msi.c +++ b/drivers/pci/msi.c @@ -105,17 +105,14 @@ static inline __attribute_const__ u32 msi_mask(unsigned x) return (1 << (1 << x)) - 1; } -static void msix_flush_writes(struct irq_desc *desc) +static inline __attribute_const__ u32 msi_capable_mask(u16 control) { - struct msi_desc *entry; + return msi_mask((control >> 1) & 7); +} - entry = get_irq_desc_msi(desc); - BUG_ON(!entry); - if (entry->msi_attrib.is_msix) { - int offset = entry->msi_attrib.entry_nr * PCI_MSIX_ENTRY_SIZE + - PCI_MSIX_ENTRY_VECTOR_CTRL_OFFSET; - readl(entry->mask_base + offset); - } +static inline __attribute_const__ u32 msi_enabled_mask(u16 control) +{ + return msi_mask((control >> 4) & 7); } /* @@ -127,32 +124,57 @@ static void msix_flush_writes(struct irq_desc *desc) * Returns 1 if it succeeded in masking the interrupt and 0 if the device * doesn't support MSI masking. */ -static int msi_set_mask_bits(struct irq_desc *desc, u32 mask, u32 flag) +static void msi_mask_irq(struct msi_desc *desc, u32 mask, u32 flag) { - struct msi_desc *entry; + u32 mask_bits = desc->masked; - entry = get_irq_desc_msi(desc); - BUG_ON(!entry); - if (entry->msi_attrib.is_msix) { - int offset = entry->msi_attrib.entry_nr * PCI_MSIX_ENTRY_SIZE + - PCI_MSIX_ENTRY_VECTOR_CTRL_OFFSET; - writel(flag, entry->mask_base + offset); - readl(entry->mask_base + offset); - } else { - int pos; - u32 mask_bits; + if (!desc->msi_attrib.maskbit) + return; + + mask_bits &= ~mask; + mask_bits |= flag; + pci_write_config_dword(desc->dev, desc->mask_pos, mask_bits); + desc->masked = mask_bits; +} + +/* + * This internal function does not flush PCI writes to the device. + * All users must ensure that they read from the device before either + * assuming that the device state is up to date, or returning out of this + * 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) +{ + u32 mask_bits = desc->masked; + unsigned offset = desc->msi_attrib.entry_nr * PCI_MSIX_ENTRY_SIZE + + PCI_MSIX_ENTRY_VECTOR_CTRL_OFFSET; + mask_bits &= ~1; + mask_bits |= flag; + writel(mask_bits, desc->mask_base + offset); + desc->masked = mask_bits; +} - if (!entry->msi_attrib.maskbit) - return 0; +static void msi_set_mask_bit(unsigned irq, u32 flag) +{ + struct msi_desc *desc = get_irq_msi(irq); - pos = entry->mask_pos; - pci_read_config_dword(entry->dev, pos, &mask_bits); - mask_bits &= ~mask; - mask_bits |= flag & mask; - pci_write_config_dword(entry->dev, pos, mask_bits); + if (desc->msi_attrib.is_msix) { + msix_mask_irq(desc, flag); + readl(desc->mask_base); /* Flush write to device */ + } else { + msi_mask_irq(desc, 1, flag); } - entry->msi_attrib.masked = !!flag; - return 1; +} + +void mask_msi_irq(unsigned int irq) +{ + msi_set_mask_bit(irq, 1); +} + +void unmask_msi_irq(unsigned int irq) +{ + msi_set_mask_bit(irq, 0); } void read_msi_msg_desc(struct irq_desc *desc, struct msi_msg *msg) @@ -230,22 +252,6 @@ void write_msi_msg(unsigned int irq, struct msi_msg *msg) write_msi_msg_desc(desc, msg); } -void mask_msi_irq(unsigned int irq) -{ - struct irq_desc *desc = irq_to_desc(irq); - - msi_set_mask_bits(desc, 1, 1); - msix_flush_writes(desc); -} - -void unmask_msi_irq(unsigned int irq) -{ - struct irq_desc *desc = irq_to_desc(irq); - - msi_set_mask_bits(desc, 1, 0); - msix_flush_writes(desc); -} - static int msi_free_irqs(struct pci_dev* dev); static struct msi_desc *alloc_msi_entry(struct pci_dev *dev) @@ -281,13 +287,9 @@ static void __pci_restore_msi_state(struct pci_dev *dev) pci_intx_for_msi(dev, 0); msi_set_enable(dev, 0); write_msi_msg(dev->irq, &entry->msg); - if (entry->msi_attrib.maskbit) { - struct irq_desc *desc = irq_to_desc(dev->irq); - msi_set_mask_bits(desc, entry->msi_attrib.maskbits_mask, - entry->msi_attrib.masked); - } pci_read_config_word(dev, pos + PCI_MSI_FLAGS, &control); + msi_mask_irq(entry, msi_capable_mask(control), entry->masked); control &= ~PCI_MSI_FLAGS_QSIZE; control |= PCI_MSI_FLAGS_ENABLE; pci_write_config_word(dev, pos + PCI_MSI_FLAGS, control); @@ -307,9 +309,8 @@ static void __pci_restore_msix_state(struct pci_dev *dev) msix_set_enable(dev, 0); list_for_each_entry(entry, &dev->msi_list, list) { - struct irq_desc *desc = irq_to_desc(entry->irq); write_msi_msg(entry->irq, &entry->msg); - msi_set_mask_bits(desc, 1, entry->msi_attrib.masked); + msix_mask_irq(entry, entry->masked); } BUG_ON(list_empty(&dev->msi_list)); @@ -342,6 +343,7 @@ static int msi_capability_init(struct pci_dev *dev) struct msi_desc *entry; int pos, ret; u16 control; + unsigned mask; msi_set_enable(dev, 0); /* Ensure msi is disabled as I set it up */ @@ -356,21 +358,16 @@ static int msi_capability_init(struct pci_dev *dev) entry->msi_attrib.is_64 = is_64bit_address(control); entry->msi_attrib.entry_nr = 0; entry->msi_attrib.maskbit = is_mask_bit_support(control); - entry->msi_attrib.masked = 1; entry->msi_attrib.default_irq = dev->irq; /* Save IOAPIC IRQ */ entry->msi_attrib.pos = pos; - if (entry->msi_attrib.maskbit) { - unsigned int base, maskbits, temp; - - base = msi_mask_bits_reg(pos, entry->msi_attrib.is_64); - entry->mask_pos = base; - /* All MSIs are unmasked by default, Mask them all */ - pci_read_config_dword(dev, base, &maskbits); - temp = msi_mask((control & PCI_MSI_FLAGS_QMASK) >> 1); - maskbits |= temp; - pci_write_config_dword(dev, base, maskbits); - entry->msi_attrib.maskbits_mask = temp; - } + + entry->mask_pos = msi_mask_bits_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); + mask = msi_capable_mask(control); + msi_mask_irq(entry, mask, mask); + list_add_tail(&entry->list, &dev->msi_list); /* Configure MSI capability structure */ @@ -435,11 +432,12 @@ static int msix_capability_init(struct pci_dev *dev, entry->msi_attrib.is_msix = 1; entry->msi_attrib.is_64 = 1; entry->msi_attrib.entry_nr = j; - entry->msi_attrib.maskbit = 1; - entry->msi_attrib.masked = 1; entry->msi_attrib.default_irq = dev->irq; entry->msi_attrib.pos = pos; entry->mask_base = base; + entry->masked = readl(base + j * PCI_MSIX_ENTRY_SIZE + + PCI_MSIX_ENTRY_VECTOR_CTRL_OFFSET); + msix_mask_irq(entry, 1); list_add_tail(&entry->list, &dev->msi_list); } @@ -556,9 +554,11 @@ int pci_enable_msi(struct pci_dev* dev) } EXPORT_SYMBOL(pci_enable_msi); -void pci_msi_shutdown(struct pci_dev* dev) +void pci_msi_shutdown(struct pci_dev *dev) { - struct msi_desc *entry; + struct msi_desc *desc; + u32 mask; + u16 ctrl; if (!pci_msi_enable || !dev || !dev->msi_enabled) return; @@ -568,18 +568,13 @@ void pci_msi_shutdown(struct pci_dev* dev) dev->msi_enabled = 0; BUG_ON(list_empty(&dev->msi_list)); - entry = list_entry(dev->msi_list.next, struct msi_desc, list); - /* Return the the pci reset with msi irqs unmasked */ - if (entry->msi_attrib.maskbit) { - u32 mask = entry->msi_attrib.maskbits_mask; - struct irq_desc *desc = irq_to_desc(dev->irq); - msi_set_mask_bits(desc, mask, ~mask); - } - if (entry->msi_attrib.is_msix) - return; + desc = list_first_entry(&dev->msi_list, struct msi_desc, list); + pci_read_config_word(dev, desc->msi_attrib.pos + PCI_MSI_FLAGS, &ctrl); + mask = msi_capable_mask(ctrl); + msi_mask_irq(desc, mask, ~mask); /* Restore dev->irq to its default pin-assertion irq */ - dev->irq = entry->msi_attrib.default_irq; + dev->irq = desc->msi_attrib.default_irq; } void pci_disable_msi(struct pci_dev* dev) diff --git a/include/linux/msi.h b/include/linux/msi.h index 5025ca4d91e4..37c1bbe546e5 100644 --- a/include/linux/msi.h +++ b/include/linux/msi.h @@ -22,14 +22,13 @@ struct msi_desc { struct { __u8 is_msix : 1; __u8 maskbit : 1; /* mask-pending bit supported ? */ - __u8 masked : 1; __u8 is_64 : 1; /* Address size: 0=32bit 1=64bit */ __u8 pos; /* Location of the msi capability */ __u16 entry_nr; /* specific enabled entry */ - __u32 maskbits_mask; /* mask bits mask */ unsigned default_irq; /* default pre-assigned irq */ - }msi_attrib; + } msi_attrib; + u32 masked; /* mask bits */ unsigned int irq; struct list_head list; -- cgit v1.2.3 From 1c8d7b0a562da06d3ebe83f01b1ed553205d1ae4 Mon Sep 17 00:00:00 2001 From: Matthew Wilcox Date: Tue, 17 Mar 2009 08:54:10 -0400 Subject: PCI MSI: Add support for multiple MSI Add the new API pci_enable_msi_block() to allow drivers to request multiple MSI and reimplement pci_enable_msi in terms of pci_enable_msi_block. Ensure that the architecture back ends don't have to know about multiple MSI. Signed-off-by: Matthew Wilcox Signed-off-by: Jesse Barnes --- Documentation/PCI/MSI-HOWTO.txt | 45 +++++++++++++++++--- arch/powerpc/kernel/msi.c | 4 ++ arch/x86/kernel/io_apic.c | 4 ++ drivers/pci/msi.c | 91 +++++++++++++++++++++++++++++------------ drivers/pci/msi.h | 6 --- include/linux/msi.h | 1 + include/linux/pci.h | 6 ++- 7 files changed, 116 insertions(+), 41 deletions(-) (limited to 'include/linux/msi.h') diff --git a/Documentation/PCI/MSI-HOWTO.txt b/Documentation/PCI/MSI-HOWTO.txt index 1c02431f1d1a..9494f6dc38eb 100644 --- a/Documentation/PCI/MSI-HOWTO.txt +++ b/Documentation/PCI/MSI-HOWTO.txt @@ -94,15 +94,48 @@ This function should be called before the driver calls request_irq() since enabling MSIs disables the pin-based IRQ and the driver will not receive interrupts on the old interrupt. -4.2.2 pci_disable_msi +4.2.2 pci_enable_msi_block + +int pci_enable_msi_block(struct pci_dev *dev, int count) + +This variation on the above call allows a device driver to request multiple +MSIs. The MSI specification only allows interrupts to be allocated in +powers of two, up to a maximum of 2^5 (32). + +If this function returns 0, it has succeeded in allocating at least as many +interrupts as the driver requested (it may have allocated more in order +to satisfy the power-of-two requirement). In this case, the function +enables MSI on this device and updates dev->irq to be the lowest of +the new interrupts assigned to it. The other interrupts assigned to +the device are in the range dev->irq to dev->irq + count - 1. + +If this function returns a negative number, it indicates an error and +the driver should not attempt to request any more MSI interrupts for +this device. If this function returns a positive number, it will be +less than 'count' and indicate the number of interrupts that could have +been allocated. In neither case will the irq value have been +updated, nor will the device have been switched into MSI mode. + +The device driver must decide what action to take if +pci_enable_msi_block() returns a value less than the number asked for. +Some devices can make use of fewer interrupts than the maximum they +request; in this case the driver should call pci_enable_msi_block() +again. Note that it is not guaranteed to succeed, even when the +'count' has been reduced to the value returned from a previous call to +pci_enable_msi_block(). This is because there are multiple constraints +on the number of vectors that can be allocated; pci_enable_msi_block() +will return as soon as it finds any constraint that doesn't allow the +call to succeed. + +4.2.3 pci_disable_msi void pci_disable_msi(struct pci_dev *dev) -This function should be used to undo the effect of pci_enable_msi(). -Calling it restores dev->irq to the pin-based interrupt number and frees -the previously allocated message signaled interrupt(s). The interrupt -may subsequently be assigned to another device, so drivers should not -cache the value of dev->irq. +This function should be used to undo the effect of pci_enable_msi() or +pci_enable_msi_block(). Calling it restores dev->irq to the pin-based +interrupt number and frees the previously allocated message signaled +interrupt(s). The interrupt may subsequently be assigned to another +device, so drivers should not cache the value of dev->irq. A device driver must always call free_irq() on the interrupt(s) for which it has called request_irq() before calling this function. diff --git a/arch/powerpc/kernel/msi.c b/arch/powerpc/kernel/msi.c index 3bb7d3dd28be..0c16e2a854e5 100644 --- a/arch/powerpc/kernel/msi.c +++ b/arch/powerpc/kernel/msi.c @@ -19,6 +19,10 @@ int arch_msi_check_device(struct pci_dev* dev, int nvec, int type) return -ENOSYS; } + /* PowerPC doesn't support multiple MSI yet */ + if (type == PCI_CAP_ID_MSI && nvec > 1) + return 1; + if (ppc_md.msi_check_device) { pr_debug("msi: Using platform check routine.\n"); return ppc_md.msi_check_device(dev, nvec, type); diff --git a/arch/x86/kernel/io_apic.c b/arch/x86/kernel/io_apic.c index bc7ac4da90d7..a09549a6321b 100644 --- a/arch/x86/kernel/io_apic.c +++ b/arch/x86/kernel/io_apic.c @@ -3510,6 +3510,10 @@ int arch_setup_msi_irqs(struct pci_dev *dev, int nvec, int type) int index = 0; #endif + /* x86 doesn't support multiple MSI yet */ + if (type == PCI_CAP_ID_MSI && nvec > 1) + return 1; + irq_want = nr_irqs_gsi; sub_handle = 0; list_for_each_entry(msidesc, &dev->msi_list, list) { diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c index adcc78242571..6f2e6295e773 100644 --- a/drivers/pci/msi.c +++ b/drivers/pci/msi.c @@ -40,6 +40,13 @@ int arch_setup_msi_irqs(struct pci_dev *dev, int nvec, int type) struct msi_desc *entry; int ret; + /* + * If an architecture wants to support multiple MSI, it needs to + * override arch_setup_msi_irqs() + */ + if (type == PCI_CAP_ID_MSI && nvec > 1) + return 1; + list_for_each_entry(entry, &dev->msi_list, list) { ret = arch_setup_msi_irq(dev, entry); if (ret < 0) @@ -58,8 +65,12 @@ void arch_teardown_msi_irqs(struct pci_dev *dev) struct msi_desc *entry; list_for_each_entry(entry, &dev->msi_list, list) { - if (entry->irq != 0) - arch_teardown_msi_irq(entry->irq); + int i, nvec; + if (entry->irq == 0) + continue; + nvec = 1 << entry->msi_attrib.multiple; + for (i = 0; i < nvec; i++) + arch_teardown_msi_irq(entry->irq + i); } } #endif @@ -163,7 +174,8 @@ static void msi_set_mask_bit(unsigned irq, u32 flag) msix_mask_irq(desc, flag); readl(desc->mask_base); /* Flush write to device */ } else { - msi_mask_irq(desc, 1, flag); + unsigned offset = irq - desc->dev->irq; + msi_mask_irq(desc, 1 << offset, flag << offset); } } @@ -229,6 +241,12 @@ void write_msi_msg_desc(struct irq_desc *desc, struct msi_msg *msg) } else { struct pci_dev *dev = entry->dev; int pos = entry->msi_attrib.pos; + u16 msgctl; + + pci_read_config_word(dev, msi_control_reg(pos), &msgctl); + msgctl &= ~PCI_MSI_FLAGS_QSIZE; + msgctl |= entry->msi_attrib.multiple << 4; + pci_write_config_word(dev, msi_control_reg(pos), msgctl); pci_write_config_dword(dev, msi_lower_address_reg(pos), msg->address_lo); @@ -291,7 +309,7 @@ static void __pci_restore_msi_state(struct pci_dev *dev) pci_read_config_word(dev, pos + PCI_MSI_FLAGS, &control); msi_mask_irq(entry, msi_capable_mask(control), entry->masked); control &= ~PCI_MSI_FLAGS_QSIZE; - control |= PCI_MSI_FLAGS_ENABLE; + control |= (entry->msi_attrib.multiple << 4) | PCI_MSI_FLAGS_ENABLE; pci_write_config_word(dev, pos + PCI_MSI_FLAGS, control); } @@ -332,13 +350,15 @@ EXPORT_SYMBOL_GPL(pci_restore_msi_state); /** * msi_capability_init - configure device's MSI capability structure * @dev: pointer to the pci_dev data structure of MSI device function + * @nvec: number of interrupts to allocate * - * Setup the MSI capability structure of device function with a single - * MSI irq, regardless of device function is capable of handling - * multiple messages. A return of zero indicates the successful setup - * of an entry zero with the new MSI irq or non-zero for otherwise. - **/ -static int msi_capability_init(struct pci_dev *dev) + * Setup the MSI capability structure of the device with the requested + * number of interrupts. A return value of zero indicates the successful + * setup of an entry with the new MSI irq. A negative return value indicates + * an error, and a positive return value indicates the number of interrupts + * which could have been allocated. + */ +static int msi_capability_init(struct pci_dev *dev, int nvec) { struct msi_desc *entry; int pos, ret; @@ -371,7 +391,7 @@ static int msi_capability_init(struct pci_dev *dev) list_add_tail(&entry->list, &dev->msi_list); /* Configure MSI capability structure */ - ret = arch_setup_msi_irqs(dev, 1, PCI_CAP_ID_MSI); + ret = arch_setup_msi_irqs(dev, nvec, PCI_CAP_ID_MSI); if (ret) { msi_free_irqs(dev); return ret; @@ -524,35 +544,48 @@ static int pci_msi_check_device(struct pci_dev* dev, int nvec, int type) } /** - * pci_enable_msi - configure device's MSI capability structure - * @dev: pointer to the pci_dev data structure of MSI device function + * pci_enable_msi_block - configure device's MSI capability structure + * @dev: device to configure + * @nvec: number of interrupts to configure * - * Setup the MSI capability structure of device function with - * a single MSI irq upon its software driver call to request for - * MSI mode enabled on its hardware device function. A return of zero - * indicates the successful setup of an entry zero with the new MSI - * irq or non-zero for otherwise. - **/ -int pci_enable_msi(struct pci_dev* dev) + * Allocate IRQs for a device with the MSI capability. + * This function returns a negative errno if an error occurs. If it + * is unable to allocate the number of interrupts requested, it returns + * the number of interrupts it might be able to allocate. If it successfully + * allocates at least the number of interrupts requested, it returns 0 and + * updates the @dev's irq member to the lowest new interrupt number; the + * other interrupt numbers allocated to this device are consecutive. + */ +int pci_enable_msi_block(struct pci_dev *dev, unsigned int nvec) { - int status; + int status, pos, maxvec; + u16 msgctl; + + pos = pci_find_capability(dev, PCI_CAP_ID_MSI); + if (!pos) + return -EINVAL; + pci_read_config_word(dev, pos + PCI_MSI_FLAGS, &msgctl); + maxvec = 1 << ((msgctl & PCI_MSI_FLAGS_QMASK) >> 1); + if (nvec > maxvec) + return maxvec; - status = pci_msi_check_device(dev, 1, PCI_CAP_ID_MSI); + status = pci_msi_check_device(dev, nvec, PCI_CAP_ID_MSI); if (status) return status; WARN_ON(!!dev->msi_enabled); - /* Check whether driver already requested for MSI-X irqs */ + /* Check whether driver already requested MSI-X irqs */ if (dev->msix_enabled) { dev_info(&dev->dev, "can't enable MSI " "(MSI-X already enabled)\n"); return -EINVAL; } - status = msi_capability_init(dev); + + status = msi_capability_init(dev, nvec); return status; } -EXPORT_SYMBOL(pci_enable_msi); +EXPORT_SYMBOL(pci_enable_msi_block); void pci_msi_shutdown(struct pci_dev *dev) { @@ -599,8 +632,12 @@ static int msi_free_irqs(struct pci_dev* dev) struct msi_desc *entry, *tmp; list_for_each_entry(entry, &dev->msi_list, list) { - if (entry->irq) - BUG_ON(irq_has_action(entry->irq)); + int i, nvec; + if (!entry->irq) + continue; + nvec = 1 << entry->msi_attrib.multiple; + for (i = 0; i < nvec; i++) + BUG_ON(irq_has_action(entry->irq + i)); } arch_teardown_msi_irqs(dev); diff --git a/drivers/pci/msi.h b/drivers/pci/msi.h index 3898f5237144..71f4df2ef654 100644 --- a/drivers/pci/msi.h +++ b/drivers/pci/msi.h @@ -20,14 +20,8 @@ #define msi_mask_bits_reg(base, is64bit) \ ( (is64bit == 1) ? base+PCI_MSI_MASK_BIT : base+PCI_MSI_MASK_BIT-4) #define msi_disable(control) control &= ~PCI_MSI_FLAGS_ENABLE -#define multi_msi_capable(control) \ - (1 << ((control & PCI_MSI_FLAGS_QMASK) >> 1)) -#define multi_msi_enable(control, num) \ - control |= (((num >> 1) << 4) & PCI_MSI_FLAGS_QSIZE); #define is_64bit_address(control) (!!(control & PCI_MSI_FLAGS_64BIT)) #define is_mask_bit_support(control) (!!(control & PCI_MSI_FLAGS_MASKBIT)) -#define msi_enable(control, num) multi_msi_enable(control, num); \ - control |= PCI_MSI_FLAGS_ENABLE #define msix_table_offset_reg(base) (base + 0x04) #define msix_pba_offset_reg(base) (base + 0x08) diff --git a/include/linux/msi.h b/include/linux/msi.h index 37c1bbe546e5..6991ab5b24d1 100644 --- a/include/linux/msi.h +++ b/include/linux/msi.h @@ -21,6 +21,7 @@ extern void write_msi_msg(unsigned int irq, struct msi_msg *msg); struct msi_desc { struct { __u8 is_msix : 1; + __u8 multiple: 3; /* log2 number of messages */ __u8 maskbit : 1; /* mask-pending bit supported ? */ __u8 is_64 : 1; /* Address size: 0=32bit 1=64bit */ __u8 pos; /* Location of the msi capability */ diff --git a/include/linux/pci.h b/include/linux/pci.h index 7baf2a5db12a..1f6c5ddaae36 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -789,7 +789,7 @@ struct msix_entry { #ifndef CONFIG_PCI_MSI -static inline int pci_enable_msi(struct pci_dev *dev) +static inline int pci_enable_msi_block(struct pci_dev *dev, unsigned int nvec) { return -1; } @@ -824,7 +824,7 @@ static inline int pci_msi_enabled(void) return 0; } #else -extern int pci_enable_msi(struct pci_dev *dev); +extern int pci_enable_msi_block(struct pci_dev *dev, unsigned int nvec); extern void pci_msi_shutdown(struct pci_dev *dev); extern void pci_disable_msi(struct pci_dev *dev); extern int pci_msix_table_size(struct pci_dev *dev); @@ -846,6 +846,8 @@ static inline int pcie_aspm_enabled(void) extern int pcie_aspm_enabled(void); #endif +#define pci_enable_msi(pdev) pci_enable_msi_block(pdev, 1) + #ifdef CONFIG_HT_IRQ /* The functions a driver should call */ int ht_create_irq(struct pci_dev *dev, int idx); -- cgit v1.2.3