Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751934AbYGEOwG (ORCPT ); Sat, 5 Jul 2008 10:52:06 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753298AbYGEOvw (ORCPT ); Sat, 5 Jul 2008 10:51:52 -0400 Received: from mail.tor.primus.ca ([216.254.136.21]:35940 "EHLO mail-08.primus.ca" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751310AbYGEOvv (ORCPT ); Sat, 5 Jul 2008 10:51:51 -0400 From: Matthew Wilcox To: linux-pci@vger.kernel.org Cc: kaneshige.kenji@jp.fujitsu.com, mingo@elte.hu, tglx@linutronix.de, davem@davemloft.net, dan.j.williams@intel.com, Martine.Silbermann@hp.com, benh@kernel.crashing.org, michael@ellerman.id.au, linux-kernel@vger.kernel.org, Matthew Wilcox , Matthew Wilcox Subject: [PATCH 2/4] PCI: Support multiple MSI Date: Sat, 5 Jul 2008 09:34:13 -0400 Message-Id: <1215264855-4372-2-git-send-email-matthew@wil.cx> X-Mailer: git-send-email 1.5.5.4 In-Reply-To: <20080705132728.GO14894@parisc-linux.org> References: <20080705132728.GO14894@parisc-linux.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 8945 Lines: 267 Add the new API pci_enable_msi_block() to allow drivers to request multiple MSIs. Reimplement pci_enable_msi in terms of pci_enable_msi_block. Add a default implementation of arch_setup_msi_block() that only allows one MSI to be requested. Signed-off-by: Matthew Wilcox --- arch/powerpc/kernel/msi.c | 2 +- drivers/pci/msi.c | 109 +++++++++++++++++++++++++++++---------------- include/linux/msi.h | 3 +- include/linux/pci.h | 6 ++- 4 files changed, 77 insertions(+), 43 deletions(-) diff --git a/arch/powerpc/kernel/msi.c b/arch/powerpc/kernel/msi.c index c62d101..317c7c8 100644 --- a/arch/powerpc/kernel/msi.c +++ b/arch/powerpc/kernel/msi.c @@ -32,7 +32,7 @@ int arch_setup_msi_irqs(struct pci_dev *dev, int nvec, int type) return ppc_md.setup_msi_irqs(dev, nvec, type); } -void arch_teardown_msi_irqs(struct pci_dev *dev) +void arch_teardown_msi_irqs(struct pci_dev *dev, int nvec) { return ppc_md.teardown_msi_irqs(dev); } diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c index 92992a8..6cbdf11 100644 --- a/drivers/pci/msi.c +++ b/drivers/pci/msi.c @@ -40,18 +40,31 @@ arch_setup_msi_irq(struct pci_dev *dev, struct msi_desc *entry) } int __attribute__ ((weak)) +arch_setup_msi_block(struct pci_dev *pdev, struct msi_desc *desc, int nvec) +{ + if (nvec > 1) + return 1; + return arch_setup_msi_irq(pdev, desc); +} + +int __attribute__ ((weak)) arch_setup_msi_irqs(struct pci_dev *dev, int nvec, int type) { - struct msi_desc *entry; + struct msi_desc *desc; int ret; - list_for_each_entry(entry, &dev->msi_list, list) { - ret = arch_setup_msi_irq(dev, entry); - if (ret) - return ret; + if (type == PCI_CAP_ID_MSI) { + desc = list_first_entry(&dev->msi_list, struct msi_desc, list); + ret = arch_setup_msi_block(dev, desc, nvec); + } else { + list_for_each_entry(desc, &dev->msi_list, list) { + ret = arch_setup_msi_irq(dev, desc); + if (ret) + break; + } } - return 0; + return ret; } void __attribute__ ((weak)) arch_teardown_msi_irq(unsigned int irq) @@ -60,13 +73,16 @@ void __attribute__ ((weak)) arch_teardown_msi_irq(unsigned int irq) } void __attribute__ ((weak)) -arch_teardown_msi_irqs(struct pci_dev *dev) +arch_teardown_msi_irqs(struct pci_dev *dev, int nvec) { 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; + if (entry->irq == 0) + continue; + for (i = 0; i < nvec; i++) + arch_teardown_msi_irq(entry->irq + i); } } @@ -350,7 +366,7 @@ EXPORT_SYMBOL_GPL(pci_restore_msi_state); * 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) +static int msi_capability_init(struct pci_dev *dev, int nr_irqs) { struct msi_desc *entry; int pos, ret; @@ -394,7 +410,7 @@ 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, nr_irqs, PCI_CAP_ID_MSI); if (ret) { msi_free_irqs(dev); return ret; @@ -546,36 +562,47 @@ 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 + * @pdev: Device to configure + * @nr_irqs: Number of IRQs requested + * + * Allocate IRQs for a device with the MSI capability. + * This function returns a negative errno if an error occurs. On success, + * this function returns the number of IRQs actually allocated. Since + * MSIs are required to be a power of two, the number of IRQs allocated + * may be rounded up to the next power of two (if the number requested is + * not a power of two). Fewer IRQs than requested may be allocated if the + * system does not have the resources for the full number. * - * 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. + * If successful, the @pdev's irq member will be updated to the lowest new + * IRQ allocated; the other IRQs allocated to this device will be consecutive. **/ -int pci_enable_msi(struct pci_dev* dev) +int pci_enable_msi_block(struct pci_dev *pdev, unsigned int nr_irqs) { int status; - status = pci_msi_check_device(dev, 1, PCI_CAP_ID_MSI); + /* MSI only supports up to 32 interrupts */ + if (nr_irqs > 32) + return 32; + + status = pci_msi_check_device(pdev, nr_irqs, PCI_CAP_ID_MSI); if (status) return status; - WARN_ON(!!dev->msi_enabled); + WARN_ON(!!pdev->msi_enabled); - /* Check whether driver already requested for MSI-X irqs */ - if (dev->msix_enabled) { + /* Check whether driver already requested MSI-X irqs */ + if (pdev->msix_enabled) { printk(KERN_INFO "PCI: %s: Can't enable MSI. " "Device already has MSI-X enabled\n", - pci_name(dev)); + pci_name(pdev)); return -EINVAL; } - status = msi_capability_init(dev); + + status = msi_capability_init(pdev, nr_irqs); return status; } -EXPORT_SYMBOL(pci_enable_msi); +EXPORT_SYMBOL(pci_enable_msi_block); void pci_msi_shutdown(struct pci_dev* dev) { @@ -621,26 +648,30 @@ EXPORT_SYMBOL(pci_disable_msi); static int msi_free_irqs(struct pci_dev* dev) { - struct msi_desc *entry, *tmp; + int i, nvec = 1; + struct msi_desc *desc, *tmp; - list_for_each_entry(entry, &dev->msi_list, list) { - if (entry->irq) - BUG_ON(irq_has_action(entry->irq)); + list_for_each_entry(desc, &dev->msi_list, list) { + nvec = 1 << desc->msi_attrib.multiple; + if (!desc->irq) + continue; + for (i = 0; i < nvec; i++) + BUG_ON(irq_has_action(desc->irq + i)); } - arch_teardown_msi_irqs(dev); + arch_teardown_msi_irqs(dev, nvec); - list_for_each_entry_safe(entry, tmp, &dev->msi_list, list) { - if (entry->msi_attrib._type == MSIX_ATTRIB) { - writel(1, entry->mask_base + entry->msi_attrib.entry_nr + list_for_each_entry_safe(desc, tmp, &dev->msi_list, list) { + if (desc->msi_attrib._type == MSIX_ATTRIB) { + writel(1, desc->mask_base + desc->msi_attrib.entry_nr * PCI_MSIX_ENTRY_SIZE + PCI_MSIX_ENTRY_VECTOR_CTRL_OFFSET); - if (list_is_last(&entry->list, &dev->msi_list)) - iounmap(entry->mask_base); + if (list_is_last(&desc->list, &dev->msi_list)) + iounmap(desc->mask_base); } - list_del(&entry->list); - kfree(entry); + list_del(&desc->list); + kfree(desc); } return 0; diff --git a/include/linux/msi.h b/include/linux/msi.h index d322148..4731fe7 100644 --- a/include/linux/msi.h +++ b/include/linux/msi.h @@ -45,9 +45,10 @@ struct msi_desc { * The arch hook for setup up msi irqs */ int arch_setup_msi_irq(struct pci_dev *dev, struct msi_desc *desc); +int arch_setup_msi_block(struct pci_dev *dev, struct msi_desc *desc, int nvec); void arch_teardown_msi_irq(unsigned int irq); extern int arch_setup_msi_irqs(struct pci_dev *dev, int nvec, int type); -extern void arch_teardown_msi_irqs(struct pci_dev *dev); +extern void arch_teardown_msi_irqs(struct pci_dev *dev, int nvec); extern int arch_msi_check_device(struct pci_dev* dev, int nvec, int type); diff --git a/include/linux/pci.h b/include/linux/pci.h index d18b1dd..f7ca7f8 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -699,7 +699,7 @@ 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 count) { return -1; } @@ -726,7 +726,7 @@ static inline void msi_remove_pci_irq_vectors(struct pci_dev *dev) static inline void pci_restore_msi_state(struct pci_dev *dev) { } #else -extern int pci_enable_msi(struct pci_dev *dev); +extern int pci_enable_msi_block(struct pci_dev *dev, unsigned int count); extern void pci_msi_shutdown(struct pci_dev *dev); extern void pci_disable_msi(struct pci_dev *dev); extern int pci_enable_msix(struct pci_dev *dev, @@ -737,6 +737,8 @@ extern void msi_remove_pci_irq_vectors(struct pci_dev *dev); extern void pci_restore_msi_state(struct pci_dev *dev); #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); -- 1.5.5.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/