diff options
author | Bjorn Helgaas <bhelgaas@google.com> | 2014-01-08 00:34:39 (GMT) |
---|---|---|
committer | Bjorn Helgaas <bhelgaas@google.com> | 2014-01-08 00:34:39 (GMT) |
commit | 04f982beb900f37bc216d63c9dbc5bdddb4a3d3a (patch) | |
tree | 0138472ccdcc5143e67b6aa78c6c17ff9dcbf494 /drivers | |
parent | ccb126545448136d36da8661f2941372554015d1 (diff) | |
parent | 302a2523c277bea0bbe8340312b09507905849ed (diff) | |
download | linux-04f982beb900f37bc216d63c9dbc5bdddb4a3d3a.tar.xz |
Merge branch 'pci/msi' into next
* pci/msi:
PCI/MSI: Add pci_enable_msi_range() and pci_enable_msix_range()
PCI/MSI: Add pci_msix_vec_count()
PCI/MSI: Remove pci_enable_msi_block_auto()
PCI/MSI: Add pci_msi_vec_count()
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/ata/ahci.c | 56 | ||||
-rw-r--r-- | drivers/pci/msi.c | 150 | ||||
-rw-r--r-- | drivers/pci/pcie/portdrv_core.c | 7 |
3 files changed, 155 insertions, 58 deletions
diff --git a/drivers/ata/ahci.c b/drivers/ata/ahci.c index e2903d0..8516f4d 100644 --- a/drivers/ata/ahci.c +++ b/drivers/ata/ahci.c @@ -1095,26 +1095,40 @@ static inline void ahci_gtf_filter_workaround(struct ata_host *host) {} #endif -int ahci_init_interrupts(struct pci_dev *pdev, struct ahci_host_priv *hpriv) +int ahci_init_interrupts(struct pci_dev *pdev, unsigned int n_ports, + struct ahci_host_priv *hpriv) { - int rc; - unsigned int maxvec; + int rc, nvec; - if (!(hpriv->flags & AHCI_HFLAG_NO_MSI)) { - rc = pci_enable_msi_block_auto(pdev, &maxvec); - if (rc > 0) { - if ((rc == maxvec) || (rc == 1)) - return rc; - /* - * Assume that advantage of multipe MSIs is negated, - * so fallback to single MSI mode to save resources - */ - pci_disable_msi(pdev); - if (!pci_enable_msi(pdev)) - return 1; - } - } + if (hpriv->flags & AHCI_HFLAG_NO_MSI) + goto intx; + + rc = pci_msi_vec_count(pdev); + if (rc < 0) + goto intx; + + /* + * 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 (rc < n_ports) + goto single_msi; + + nvec = rc; + rc = pci_enable_msi_block(pdev, nvec); + if (rc) + goto intx; + return nvec; + +single_msi: + rc = pci_enable_msi(pdev); + if (rc) + goto intx; + return 1; + +intx: pci_intx(pdev, 1); return 0; } @@ -1281,10 +1295,6 @@ static int ahci_init_one(struct pci_dev *pdev, const struct pci_device_id *ent) hpriv->mmio = pcim_iomap_table(pdev)[ahci_pci_bar]; - n_msis = ahci_init_interrupts(pdev, hpriv); - if (n_msis > 1) - hpriv->flags |= AHCI_HFLAG_MULTI_MSI; - /* save initial config */ ahci_pci_save_initial_config(pdev, hpriv); @@ -1339,6 +1349,10 @@ static int ahci_init_one(struct pci_dev *pdev, const struct pci_device_id *ent) */ n_ports = max(ahci_nr_ports(hpriv->cap), fls(hpriv->port_map)); + n_msis = ahci_init_interrupts(pdev, n_ports, hpriv); + if (n_msis > 1) + hpriv->flags |= AHCI_HFLAG_MULTI_MSI; + host = ata_host_alloc_pinfo(&pdev->dev, ppi, n_ports); if (!host) return -ENOMEM; diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c index 22957aa..7a0fec6 100644 --- a/drivers/pci/msi.c +++ b/drivers/pci/msi.c @@ -852,6 +852,31 @@ static int pci_msi_check_device(struct pci_dev *dev, int nvec, int type) } /** + * pci_msi_vec_count - Return the number of MSI vectors a device can send + * @dev: device to report about + * + * This function returns the number of MSI vectors a device requested via + * Multiple Message Capable register. It returns a negative errno if the + * device is not capable sending MSI interrupts. Otherwise, the call succeeds + * and returns a power of two, up to a maximum of 2^5 (32), according to the + * MSI specification. + **/ +int pci_msi_vec_count(struct pci_dev *dev) +{ + int ret; + u16 msgctl; + + if (!dev->msi_cap) + return -EINVAL; + + pci_read_config_word(dev, dev->msi_cap + PCI_MSI_FLAGS, &msgctl); + ret = 1 << ((msgctl & PCI_MSI_FLAGS_QMASK) >> 1); + + return ret; +} +EXPORT_SYMBOL(pci_msi_vec_count); + +/** * pci_enable_msi_block - configure device's MSI capability structure * @dev: device to configure * @nvec: number of interrupts to configure @@ -867,13 +892,13 @@ static int pci_msi_check_device(struct pci_dev *dev, int nvec, int type) int pci_enable_msi_block(struct pci_dev *dev, int nvec) { int status, maxvec; - u16 msgctl; - if (!dev->msi_cap || dev->current_state != PCI_D0) + if (dev->current_state != PCI_D0) return -EINVAL; - pci_read_config_word(dev, dev->msi_cap + PCI_MSI_FLAGS, &msgctl); - maxvec = 1 << ((msgctl & PCI_MSI_FLAGS_QMASK) >> 1); + maxvec = pci_msi_vec_count(dev); + if (maxvec < 0) + return maxvec; if (nvec > maxvec) return maxvec; @@ -895,31 +920,6 @@ int pci_enable_msi_block(struct pci_dev *dev, int nvec) } EXPORT_SYMBOL(pci_enable_msi_block); -int pci_enable_msi_block_auto(struct pci_dev *dev, int *maxvec) -{ - int ret, nvec; - u16 msgctl; - - if (!dev->msi_cap || dev->current_state != PCI_D0) - return -EINVAL; - - pci_read_config_word(dev, dev->msi_cap + PCI_MSI_FLAGS, &msgctl); - ret = 1 << ((msgctl & PCI_MSI_FLAGS_QMASK) >> 1); - - if (maxvec) - *maxvec = ret; - - do { - nvec = ret; - ret = pci_enable_msi_block(dev, nvec); - } while (ret > 0); - - if (ret < 0) - return ret; - return nvec; -} -EXPORT_SYMBOL(pci_enable_msi_block_auto); - void pci_msi_shutdown(struct pci_dev *dev) { struct msi_desc *desc; @@ -957,19 +957,25 @@ void pci_disable_msi(struct pci_dev *dev) EXPORT_SYMBOL(pci_disable_msi); /** - * pci_msix_table_size - return the number of device's MSI-X table entries + * pci_msix_vec_count - return the number of device's MSI-X table entries * @dev: pointer to the pci_dev data structure of MSI-X device function - */ -int pci_msix_table_size(struct pci_dev *dev) + + * This function returns the number of device's MSI-X table entries and + * therefore the number of MSI-X vectors device is capable of sending. + * It returns a negative errno if the device is not capable of sending MSI-X + * interrupts. + **/ +int pci_msix_vec_count(struct pci_dev *dev) { u16 control; if (!dev->msix_cap) - return 0; + return -EINVAL; pci_read_config_word(dev, dev->msix_cap + PCI_MSIX_FLAGS, &control); return msix_table_size(control); } +EXPORT_SYMBOL(pci_msix_vec_count); /** * pci_enable_msix - configure device's MSI-X capability structure @@ -998,7 +1004,9 @@ int pci_enable_msix(struct pci_dev *dev, struct msix_entry *entries, int nvec) if (status) return status; - nr_entries = pci_msix_table_size(dev); + nr_entries = pci_msix_vec_count(dev); + if (nr_entries < 0) + return nr_entries; if (nvec > nr_entries) return nr_entries; @@ -1103,3 +1111,77 @@ void pci_msi_init_pci_dev(struct pci_dev *dev) if (dev->msix_cap) msix_set_enable(dev, 0); } + +/** + * pci_enable_msi_range - configure device's MSI capability structure + * @dev: device to configure + * @minvec: minimal number of interrupts to configure + * @maxvec: maximum number of interrupts to configure + * + * This function tries to allocate a maximum possible number of interrupts in a + * range between @minvec and @maxvec. It returns a negative errno if an error + * occurs. If it succeeds, it returns the actual number of interrupts allocated + * 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_range(struct pci_dev *dev, int minvec, int maxvec) +{ + int nvec = maxvec; + int rc; + + if (maxvec < minvec) + return -ERANGE; + + do { + rc = pci_enable_msi_block(dev, nvec); + if (rc < 0) { + return rc; + } else if (rc > 0) { + if (rc < minvec) + return -ENOSPC; + nvec = rc; + } + } while (rc); + + return nvec; +} +EXPORT_SYMBOL(pci_enable_msi_range); + +/** + * pci_enable_msix_range - configure device's MSI-X capability structure + * @dev: pointer to the pci_dev data structure of MSI-X device function + * @entries: pointer to an array of MSI-X entries + * @minvec: minimum number of MSI-X irqs requested + * @maxvec: maximum number of MSI-X irqs requested + * + * Setup the MSI-X capability structure of device function with a maximum + * possible number of interrupts in the range between @minvec and @maxvec + * upon its software driver call to request for MSI-X mode enabled on its + * hardware device function. It returns a negative errno if an error occurs. + * If it succeeds, it returns the actual number of interrupts allocated and + * indicates the successful configuration of MSI-X capability structure + * with new allocated MSI-X interrupts. + **/ +int pci_enable_msix_range(struct pci_dev *dev, struct msix_entry *entries, + int minvec, int maxvec) +{ + int nvec = maxvec; + int rc; + + if (maxvec < minvec) + return -ERANGE; + + do { + rc = pci_enable_msix(dev, entries, nvec); + if (rc < 0) { + return rc; + } else if (rc > 0) { + if (rc < minvec) + return -ENOSPC; + nvec = rc; + } + } while (rc); + + return nvec; +} +EXPORT_SYMBOL(pci_enable_msix_range); diff --git a/drivers/pci/pcie/portdrv_core.c b/drivers/pci/pcie/portdrv_core.c index 16a1ce4..986f8ea 100644 --- a/drivers/pci/pcie/portdrv_core.c +++ b/drivers/pci/pcie/portdrv_core.c @@ -79,9 +79,10 @@ static int pcie_port_enable_msix(struct pci_dev *dev, int *vectors, int mask) u16 reg16; u32 reg32; - nr_entries = pci_msix_table_size(dev); - if (!nr_entries) - return -EINVAL; + nr_entries = pci_msix_vec_count(dev); + if (nr_entries < 0) + return nr_entries; + BUG_ON(!nr_entries); if (nr_entries > PCIE_PORT_MAX_MSIX_ENTRIES) nr_entries = PCIE_PORT_MAX_MSIX_ENTRIES; |