From 0b9e2988ab2261fd6d4a0039edf81ed1e3662be8 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Mon, 5 Sep 2016 17:21:45 +0200 Subject: [PATCH] ahci: use pci_alloc_irq_vectors Use the new pci_alloc_irq_vectors API to allocate MSI-X and MSI vectors. The big advantage over the old code is that we can use the same API for MSI and MSI-X, and that we don't need to store the MSI-X vector mapping in driver-private data structures. This first conversion keeps the probe order as-is: MSI-X multi vector, MSI multi vector, MSI single vector, MSI-X single vector and last a single least legacy interrupt line. There is one small change of behavior: we now check the "MSI Revert to Single Message" flag for MSI-X in addition to MSI. Because the API to find the Linux IRQ number for a MSI/MSI-X vector is PCI specific, but libahaci is bus-agnostic I had to a get_irq_vector function pointer to struct ahci_host_priv. The alternative would be to move the multi-vector case of ahci_host_activate to ahci.c and just call ata_host_activate directly from the others users of ahci_host_activate. Signed-off-by: Christoph Hellwig Signed-off-by: Tejun Heo --- drivers/ata/ahci.c | 149 +++++++++--------------------------------- drivers/ata/ahci.h | 24 ++----- drivers/ata/libahci.c | 11 +++- 3 files changed, 45 insertions(+), 139 deletions(-) diff --git a/drivers/ata/ahci.c b/drivers/ata/ahci.c index 90eabaf81215..ba5f11cebee2 100644 --- a/drivers/ata/ahci.c +++ b/drivers/ata/ahci.c @@ -1400,142 +1400,56 @@ static irqreturn_t ahci_thunderx_irq_handler(int irq, void *dev_instance) } #endif -/* - * ahci_init_msix() - optionally enable per-port MSI-X otherwise defer - * to single msi. - */ -static int ahci_init_msix(struct pci_dev *pdev, unsigned int n_ports, - struct ahci_host_priv *hpriv, unsigned long flags) +static int ahci_get_irq_vector(struct ata_host *host, int port) { - int nvec, i, rc; - - /* Do not init MSI-X if MSI is disabled for the device */ - if (hpriv->flags & AHCI_HFLAG_NO_MSI) - return -ENODEV; - - nvec = pci_msix_vec_count(pdev); - if (nvec < 0) - return nvec; - - /* - * Proper MSI-X implementations will have a vector per-port. - * Barring that, we prefer single-MSI over single-MSIX. If this - * check fails (not enough MSI-X vectors for all ports) we will - * be called again with the flag clear iff ahci_init_msi() - * fails. - */ - if (flags & AHCI_HFLAG_MULTI_MSIX) { - if (nvec < n_ports) - return -ENODEV; - nvec = n_ports; - } else if (nvec) { - nvec = 1; - } else { - /* - * Emit dev_err() since this was the non-legacy irq - * method of last resort. - */ - rc = -ENODEV; - goto fail; - } - - for (i = 0; i < nvec; i++) - hpriv->msix[i].entry = i; - rc = pci_enable_msix_exact(pdev, hpriv->msix, nvec); - if (rc < 0) - goto fail; - - if (nvec > 1) - hpriv->flags |= AHCI_HFLAG_MULTI_MSIX; - hpriv->irq = hpriv->msix[0].vector; /* for single msi-x */ - - return nvec; -fail: - dev_err(&pdev->dev, - "failed to enable MSI-X with error %d, # of vectors: %d\n", - rc, nvec); - - return rc; + return pci_irq_vector(to_pci_dev(host->dev), port); } static int ahci_init_msi(struct pci_dev *pdev, unsigned int n_ports, struct ahci_host_priv *hpriv) { - int rc, nvec; + int nvec; if (hpriv->flags & AHCI_HFLAG_NO_MSI) return -ENODEV; - nvec = pci_msi_vec_count(pdev); - if (nvec < 0) - return nvec; - /* * If number of MSIs is less than number of ports then Sharing Last * Message mode could be enforced. In this case assume that advantage * of multipe MSIs is negated and use single MSI mode instead. */ - if (nvec < n_ports) - goto single_msi; - - rc = pci_enable_msi_exact(pdev, nvec); - if (rc == -ENOSPC) - goto single_msi; - if (rc < 0) - return rc; + nvec = pci_alloc_irq_vectors(pdev, n_ports, INT_MAX, + PCI_IRQ_MSIX | PCI_IRQ_MSI); + if (nvec > 0) { + if (!(readl(hpriv->mmio + HOST_CTL) & HOST_MRSM)) { + hpriv->get_irq_vector = ahci_get_irq_vector; + hpriv->flags |= AHCI_HFLAG_MULTI_MSI; + return nvec; + } - /* fallback to single MSI mode if the controller enforced MRSM mode */ - if (readl(hpriv->mmio + HOST_CTL) & HOST_MRSM) { - pci_disable_msi(pdev); + /* + * Fallback to single MSI mode if the controller enforced MRSM + * mode. + */ printk(KERN_INFO "ahci: MRSM is on, fallback to single MSI\n"); - goto single_msi; + pci_free_irq_vectors(pdev); } - if (nvec > 1) - hpriv->flags |= AHCI_HFLAG_MULTI_MSI; - - goto out; - -single_msi: - nvec = 1; - - rc = pci_enable_msi(pdev); - if (rc < 0) - return rc; -out: - hpriv->irq = pdev->irq; - - return nvec; -} - -static int ahci_init_interrupts(struct pci_dev *pdev, unsigned int n_ports, - struct ahci_host_priv *hpriv) -{ - int nvec; - /* - * Try to enable per-port MSI-X. If the host is not capable - * fall back to single MSI before finally attempting single - * MSI-X. + * -ENOSPC indicated we don't have enough vectors. Don't bother trying + * a single vectors for any other error: */ - nvec = ahci_init_msix(pdev, n_ports, hpriv, AHCI_HFLAG_MULTI_MSIX); - if (nvec >= 0) + if (nvec < 0 && nvec != -ENOSPC) return nvec; - nvec = ahci_init_msi(pdev, n_ports, hpriv); - if (nvec >= 0) - return nvec; - - /* try single-msix */ - nvec = ahci_init_msix(pdev, n_ports, hpriv, 0); - if (nvec >= 0) + /* + * If the host is not capable of supporting per-port vectors, fall + * back to single MSI before finally attempting single MSI-X. + */ + nvec = pci_alloc_irq_vectors(pdev, 1, 1, PCI_IRQ_MSI); + if (nvec == 1) return nvec; - - /* legacy intx interrupts */ - pci_intx(pdev, 1); - hpriv->irq = pdev->irq; - - return 0; + return pci_alloc_irq_vectors(pdev, 1, 1, PCI_IRQ_MSIX); } static int ahci_init_one(struct pci_dev *pdev, const struct pci_device_id *ent) @@ -1698,11 +1612,12 @@ static int ahci_init_one(struct pci_dev *pdev, const struct pci_device_id *ent) if (!host) return -ENOMEM; host->private_data = hpriv; - hpriv->msix = devm_kzalloc(&pdev->dev, - sizeof(struct msix_entry) * n_ports, GFP_KERNEL); - if (!hpriv->msix) - return -ENOMEM; - ahci_init_interrupts(pdev, n_ports, hpriv); + + if (ahci_init_msi(pdev, n_ports, hpriv) < 0) { + /* legacy intx interrupts */ + pci_intx(pdev, 1); + } + hpriv->irq = pdev->irq; if (!(hpriv->cap & HOST_CAP_SSS) || ahci_ignore_sss) host->flags |= ATA_HOST_PARALLEL_SCAN; diff --git a/drivers/ata/ahci.h b/drivers/ata/ahci.h index 70b06bcfb7e3..0cc08f892fea 100644 --- a/drivers/ata/ahci.h +++ b/drivers/ata/ahci.h @@ -242,12 +242,10 @@ enum { AHCI_HFLAG_NO_FBS = (1 << 18), /* no FBS */ #ifdef CONFIG_PCI_MSI - AHCI_HFLAG_MULTI_MSI = (1 << 20), /* multiple PCI MSIs */ - AHCI_HFLAG_MULTI_MSIX = (1 << 21), /* per-port MSI-X */ + AHCI_HFLAG_MULTI_MSI = (1 << 20), /* per-port MSI(-X) */ #else /* compile out MSI infrastructure */ AHCI_HFLAG_MULTI_MSI = 0, - AHCI_HFLAG_MULTI_MSIX = 0, #endif AHCI_HFLAG_WAKE_BEFORE_STOP = (1 << 22), /* wake before DMA stop */ @@ -351,7 +349,6 @@ struct ahci_host_priv { * the PHY position in this array. */ struct phy **phys; - struct msix_entry *msix; /* Optional MSI-X support */ unsigned nports; /* Number of ports */ void *plat_data; /* Other platform data */ unsigned int irq; /* interrupt line */ @@ -362,22 +359,11 @@ struct ahci_host_priv { */ void (*start_engine)(struct ata_port *ap); irqreturn_t (*irq_handler)(int irq, void *dev_instance); -}; -#ifdef CONFIG_PCI_MSI -static inline int ahci_irq_vector(struct ahci_host_priv *hpriv, int port) -{ - if (hpriv->flags & AHCI_HFLAG_MULTI_MSIX) - return hpriv->msix[port].vector; - else - return hpriv->irq + port; -} -#else -static inline int ahci_irq_vector(struct ahci_host_priv *hpriv, int port) -{ - return hpriv->irq; -} -#endif + /* only required for per-port MSI(-X) support */ + int (*get_irq_vector)(struct ata_host *host, + int port); +}; extern int ahci_ignore_sss; diff --git a/drivers/ata/libahci.c b/drivers/ata/libahci.c index 5a1329e31609..0d028ead99e8 100644 --- a/drivers/ata/libahci.c +++ b/drivers/ata/libahci.c @@ -2378,7 +2378,7 @@ static int ahci_port_start(struct ata_port *ap) /* * Switch to per-port locking in case each port has its own MSI vector. */ - if (hpriv->flags & (AHCI_HFLAG_MULTI_MSI | AHCI_HFLAG_MULTI_MSIX)) { + if (hpriv->flags & AHCI_HFLAG_MULTI_MSI) { spin_lock_init(&pp->lock); ap->lock = &pp->lock; } @@ -2520,7 +2520,7 @@ static int ahci_host_activate_multi_irqs(struct ata_host *host, */ for (i = 0; i < host->n_ports; i++) { struct ahci_port_priv *pp = host->ports[i]->private_data; - int irq = ahci_irq_vector(hpriv, i); + int irq = hpriv->get_irq_vector(host, i); /* Do not receive interrupts sent by dummy ports */ if (!pp) { @@ -2556,10 +2556,15 @@ int ahci_host_activate(struct ata_host *host, struct scsi_host_template *sht) int irq = hpriv->irq; int rc; - if (hpriv->flags & (AHCI_HFLAG_MULTI_MSI | AHCI_HFLAG_MULTI_MSIX)) { + if (hpriv->flags & AHCI_HFLAG_MULTI_MSI) { if (hpriv->irq_handler) dev_warn(host->dev, "both AHCI_HFLAG_MULTI_MSI flag set and custom irq handler implemented\n"); + if (!hpriv->get_irq_vector) { + dev_err(host->dev, + "AHCI_HFLAG_MULTI_MSI requires ->get_irq_vector!\n"); + return -EIO; + } rc = ahci_host_activate_multi_irqs(host, sht); } else { -- 2.20.1