From f59dca27d20c73500c4a88ab9a077e40669755db Mon Sep 17 00:00:00 2001 From: Wei Yang Date: Wed, 25 Mar 2015 16:23:46 +0800 Subject: [PATCH] PCI: Refresh First VF Offset and VF Stride when updating NumVFs The First VF Offset and VF Stride fields depend on the NumVFs setting, so refresh the cached fields in struct pci_sriov when updating NumVFs. See the SR-IOV spec r1.1, sec 3.3.9 and 3.3.10. [bhelgaas: changelog, remove kernel-doc comment marker] Signed-off-by: Wei Yang Acked-by: Bjorn Helgaas Signed-off-by: Benjamin Herrenschmidt --- drivers/pci/iov.c | 23 +++++++++++++++++++---- 1 file changed, 19 insertions(+), 4 deletions(-) diff --git a/drivers/pci/iov.c b/drivers/pci/iov.c index 27b98c361823..a8752c2c2b53 100644 --- a/drivers/pci/iov.c +++ b/drivers/pci/iov.c @@ -31,6 +31,21 @@ static inline u8 virtfn_devfn(struct pci_dev *dev, int id) dev->sriov->stride * id) & 0xff; } +/* + * Per SR-IOV spec sec 3.3.10 and 3.3.11, First VF Offset and VF Stride may + * change when NumVFs changes. + * + * Update iov->offset and iov->stride when NumVFs is written. + */ +static inline void pci_iov_set_numvfs(struct pci_dev *dev, int nr_virtfn) +{ + struct pci_sriov *iov = dev->sriov; + + pci_write_config_word(dev, iov->pos + PCI_SRIOV_NUM_VF, nr_virtfn); + pci_read_config_word(dev, iov->pos + PCI_SRIOV_VF_OFFSET, &iov->offset); + pci_read_config_word(dev, iov->pos + PCI_SRIOV_VF_STRIDE, &iov->stride); +} + static struct pci_bus *virtfn_add_bus(struct pci_bus *bus, int busnr) { struct pci_bus *child; @@ -253,7 +268,7 @@ static int sriov_enable(struct pci_dev *dev, int nr_virtfn) return rc; } - pci_write_config_word(dev, iov->pos + PCI_SRIOV_NUM_VF, nr_virtfn); + pci_iov_set_numvfs(dev, nr_virtfn); iov->ctrl |= PCI_SRIOV_CTRL_VFE | PCI_SRIOV_CTRL_MSE; pci_cfg_access_lock(dev); pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl); @@ -282,7 +297,7 @@ failed: iov->ctrl &= ~(PCI_SRIOV_CTRL_VFE | PCI_SRIOV_CTRL_MSE); pci_cfg_access_lock(dev); pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl); - pci_write_config_word(dev, iov->pos + PCI_SRIOV_NUM_VF, 0); + pci_iov_set_numvfs(dev, 0); ssleep(1); pci_cfg_access_unlock(dev); @@ -313,7 +328,7 @@ static void sriov_disable(struct pci_dev *dev) sysfs_remove_link(&dev->dev.kobj, "dep_link"); iov->num_VFs = 0; - pci_write_config_word(dev, iov->pos + PCI_SRIOV_NUM_VF, 0); + pci_iov_set_numvfs(dev, 0); } static int sriov_init(struct pci_dev *dev, int pos) @@ -452,7 +467,7 @@ static void sriov_restore_state(struct pci_dev *dev) pci_update_resource(dev, i); pci_write_config_dword(dev, iov->pos + PCI_SRIOV_SYS_PGSIZE, iov->pgsz); - pci_write_config_word(dev, iov->pos + PCI_SRIOV_NUM_VF, iov->num_VFs); + pci_iov_set_numvfs(dev, iov->num_VFs); pci_write_config_word(dev, iov->pos + PCI_SRIOV_CTRL, iov->ctrl); if (iov->ctrl & PCI_SRIOV_CTRL_VFE) msleep(100); -- 2.39.2