diff options
Diffstat (limited to 'drivers/dma/ioat_dca.c')
| -rw-r--r-- | drivers/dma/ioat_dca.c | 164 |
1 files changed, 164 insertions, 0 deletions
diff --git a/drivers/dma/ioat_dca.c b/drivers/dma/ioat_dca.c index ba985715b803..0fa8a98051a8 100644 --- a/drivers/dma/ioat_dca.c +++ b/drivers/dma/ioat_dca.c @@ -261,3 +261,167 @@ struct dca_provider *ioat_dca_init(struct pci_dev *pdev, void __iomem *iobase) return dca; } + +static int ioat2_dca_add_requester(struct dca_provider *dca, struct device *dev) +{ + struct ioat_dca_priv *ioatdca = dca_priv(dca); + struct pci_dev *pdev; + int i; + u16 id; + u16 global_req_table; + + /* This implementation only supports PCI-Express */ + if (dev->bus != &pci_bus_type) + return -ENODEV; + pdev = to_pci_dev(dev); + id = dcaid_from_pcidev(pdev); + + if (ioatdca->requester_count == ioatdca->max_requesters) + return -ENODEV; + + for (i = 0; i < ioatdca->max_requesters; i++) { + if (ioatdca->req_slots[i].pdev == NULL) { + /* found an empty slot */ + ioatdca->requester_count++; + ioatdca->req_slots[i].pdev = pdev; + ioatdca->req_slots[i].rid = id; + global_req_table = + readw(ioatdca->dca_base + IOAT_DCA_GREQID_OFFSET); + writel(id | IOAT_DCA_GREQID_VALID, + ioatdca->iobase + global_req_table + (i * 4)); + return i; + } + } + /* Error, ioatdma->requester_count is out of whack */ + return -EFAULT; +} + +static int ioat2_dca_remove_requester(struct dca_provider *dca, + struct device *dev) +{ + struct ioat_dca_priv *ioatdca = dca_priv(dca); + struct pci_dev *pdev; + int i; + u16 global_req_table; + + /* This implementation only supports PCI-Express */ + if (dev->bus != &pci_bus_type) + return -ENODEV; + pdev = to_pci_dev(dev); + + for (i = 0; i < ioatdca->max_requesters; i++) { + if (ioatdca->req_slots[i].pdev == pdev) { + global_req_table = + readw(ioatdca->dca_base + IOAT_DCA_GREQID_OFFSET); + writel(0, ioatdca->iobase + global_req_table + (i * 4)); + ioatdca->req_slots[i].pdev = NULL; + ioatdca->req_slots[i].rid = 0; + ioatdca->requester_count--; + return i; + } + } + return -ENODEV; +} + +static u8 ioat2_dca_get_tag(struct dca_provider *dca, int cpu) +{ + u8 tag; + + tag = ioat_dca_get_tag(dca, cpu); + tag = (~tag) & 0x1F; + return tag; +} + +static struct dca_ops ioat2_dca_ops = { + .add_requester = ioat2_dca_add_requester, + .remove_requester = ioat2_dca_remove_requester, + .get_tag = ioat2_dca_get_tag, +}; + +static int ioat2_dca_count_dca_slots(void *iobase, u16 dca_offset) +{ + int slots = 0; + u32 req; + u16 global_req_table; + + global_req_table = readw(iobase + dca_offset + IOAT_DCA_GREQID_OFFSET); + if (global_req_table == 0) + return 0; + do { + req = readl(iobase + global_req_table + (slots * sizeof(u32))); + slots++; + } while ((req & IOAT_DCA_GREQID_LASTID) == 0); + + return slots; +} + +struct dca_provider *ioat2_dca_init(struct pci_dev *pdev, void __iomem *iobase) +{ + struct dca_provider *dca; + struct ioat_dca_priv *ioatdca; + int slots; + int i; + int err; + u32 tag_map; + u16 dca_offset; + u16 csi_fsb_control; + u16 pcie_control; + u8 bit; + + if (!system_has_dca_enabled(pdev)) + return NULL; + + dca_offset = readw(iobase + IOAT_DCAOFFSET_OFFSET); + if (dca_offset == 0) + return NULL; + + slots = ioat2_dca_count_dca_slots(iobase, dca_offset); + if (slots == 0) + return NULL; + + dca = alloc_dca_provider(&ioat2_dca_ops, + sizeof(*ioatdca) + + (sizeof(struct ioat_dca_slot) * slots)); + if (!dca) + return NULL; + + ioatdca = dca_priv(dca); + ioatdca->iobase = iobase; + ioatdca->dca_base = iobase + dca_offset; + ioatdca->max_requesters = slots; + + /* some bios might not know to turn these on */ + csi_fsb_control = readw(ioatdca->dca_base + IOAT_FSB_CAP_ENABLE_OFFSET); + if ((csi_fsb_control & IOAT_FSB_CAP_ENABLE_PREFETCH) == 0) { + csi_fsb_control |= IOAT_FSB_CAP_ENABLE_PREFETCH; + writew(csi_fsb_control, + ioatdca->dca_base + IOAT_FSB_CAP_ENABLE_OFFSET); + } + pcie_control = readw(ioatdca->dca_base + IOAT_PCI_CAP_ENABLE_OFFSET); + if ((pcie_control & IOAT_PCI_CAP_ENABLE_MEMWR) == 0) { + pcie_control |= IOAT_PCI_CAP_ENABLE_MEMWR; + writew(pcie_control, + ioatdca->dca_base + IOAT_PCI_CAP_ENABLE_OFFSET); + } + + + /* TODO version, compatibility and configuration checks */ + + /* copy out the APIC to DCA tag map */ + tag_map = readl(ioatdca->dca_base + IOAT_APICID_TAG_MAP_OFFSET); + for (i = 0; i < 5; i++) { + bit = (tag_map >> (4 * i)) & 0x0f; + if (bit < 8) + ioatdca->tag_map[i] = bit | DCA_TAG_MAP_VALID; + else + ioatdca->tag_map[i] = 0; + } + + err = register_dca_provider(dca, &pdev->dev); + if (err) { + free_dca_provider(dca); + return NULL; + } + + return dca; +} |