--- /dev/null
+/*
+ * Intel I/OAT DMA Linux driver
+ * Copyright(c) 2007 - 2009 Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * The full GNU General Public License is included in this distribution in
+ * the file called "COPYING".
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/pci.h>
+#include <linux/smp.h>
+#include <linux/interrupt.h>
+#include <linux/dca.h>
+
+/* either a kernel change is needed, or we need something like this in kernel */
+#ifndef CONFIG_SMP
+#include <asm/smp.h>
+#undef cpu_physical_id
+#define cpu_physical_id(cpu) (cpuid_ebx(1) >> 24)
+#endif
+
+#include "dma.h"
+#include "registers.h"
+#include "dma_v2.h"
+
+/*
+ * Bit 7 of a tag map entry is the "valid" bit, if it is set then bits 0:6
+ * contain the bit number of the APIC ID to map into the DCA tag. If the valid
+ * bit is not set, then the value must be 0 or 1 and defines the bit in the tag.
+ */
+#define DCA_TAG_MAP_VALID 0x80
+
+#define DCA3_TAG_MAP_BIT_TO_INV 0x80
+#define DCA3_TAG_MAP_BIT_TO_SEL 0x40
+#define DCA3_TAG_MAP_LITERAL_VAL 0x1
+
+#define DCA_TAG_MAP_MASK 0xDF
+
+/* expected tag map bytes for I/OAT ver.2 */
+#define DCA2_TAG_MAP_BYTE0 0x80
+#define DCA2_TAG_MAP_BYTE1 0x0
+#define DCA2_TAG_MAP_BYTE2 0x81
+#define DCA2_TAG_MAP_BYTE3 0x82
+#define DCA2_TAG_MAP_BYTE4 0x82
+
+/* verify if tag map matches expected values */
+static inline int dca2_tag_map_valid(u8 *tag_map)
+{
+ return ((tag_map[0] == DCA2_TAG_MAP_BYTE0) &&
+ (tag_map[1] == DCA2_TAG_MAP_BYTE1) &&
+ (tag_map[2] == DCA2_TAG_MAP_BYTE2) &&
+ (tag_map[3] == DCA2_TAG_MAP_BYTE3) &&
+ (tag_map[4] == DCA2_TAG_MAP_BYTE4));
+}
+
+/*
+ * "Legacy" DCA systems do not implement the DCA register set in the
+ * I/OAT device. Software needs direct support for their tag mappings.
+ */
+
+#define APICID_BIT(x) (DCA_TAG_MAP_VALID | (x))
+#define IOAT_TAG_MAP_LEN 8
+
+static u8 ioat_tag_map_BNB[IOAT_TAG_MAP_LEN] = {
+ 1, APICID_BIT(1), APICID_BIT(2), APICID_BIT(2), };
+static u8 ioat_tag_map_SCNB[IOAT_TAG_MAP_LEN] = {
+ 1, APICID_BIT(1), APICID_BIT(2), APICID_BIT(2), };
+static u8 ioat_tag_map_CNB[IOAT_TAG_MAP_LEN] = {
+ 1, APICID_BIT(1), APICID_BIT(3), APICID_BIT(4), APICID_BIT(2), };
+static u8 ioat_tag_map_UNISYS[IOAT_TAG_MAP_LEN] = { 0 };
+
+/* pack PCI B/D/F into a u16 */
+static inline u16 dcaid_from_pcidev(struct pci_dev *pci)
+{
+ return (pci->bus->number << 8) | pci->devfn;
+}
+
+static int dca_enabled_in_bios(struct pci_dev *pdev)
+{
+ /* CPUID level 9 returns DCA configuration */
+ /* Bit 0 indicates DCA enabled by the BIOS */
+ unsigned long cpuid_level_9;
+ int res;
+
+ cpuid_level_9 = cpuid_eax(9);
+ res = test_bit(0, &cpuid_level_9);
+ if (!res)
+ dev_dbg(&pdev->dev, "DCA is disabled in BIOS\n");
+
+ return res;
+}
+
+int system_has_dca_enabled(struct pci_dev *pdev)
+{
+ if (boot_cpu_has(X86_FEATURE_DCA))
+ return dca_enabled_in_bios(pdev);
+
+ dev_dbg(&pdev->dev, "boot cpu doesn't have X86_FEATURE_DCA\n");
+ return 0;
+}
+
+struct ioat_dca_slot {
+ struct pci_dev *pdev; /* requester device */
+ u16 rid; /* requester id, as used by IOAT */
+};
+
+#define IOAT_DCA_MAX_REQ 6
+#define IOAT3_DCA_MAX_REQ 2
+
+struct ioat_dca_priv {
+ void __iomem *iobase;
+ void __iomem *dca_base;
+ int max_requesters;
+ int requester_count;
+ u8 tag_map[IOAT_TAG_MAP_LEN];
+ struct ioat_dca_slot req_slots[0];
+};
+
+/* 5000 series chipset DCA Port Requester ID Table Entry Format
+ * [15:8] PCI-Express Bus Number
+ * [7:3] PCI-Express Device Number
+ * [2:0] PCI-Express Function Number
+ *
+ * 5000 series chipset DCA control register format
+ * [7:1] Reserved (0)
+ * [0] Ignore Function Number
+ */
+
+static int ioat_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;
+
+ /* This implementation only supports PCI-Express */
+ if (!dev_is_pci(dev))
+ 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;
+ writew(id, ioatdca->dca_base + (i * 4));
+ /* make sure the ignore function bit is off */
+ writeb(0, ioatdca->dca_base + (i * 4) + 2);
+ return i;
+ }
+ }
+ /* Error, ioatdma->requester_count is out of whack */
+ return -EFAULT;
+}
+
+static int ioat_dca_remove_requester(struct dca_provider *dca,
+ struct device *dev)
+{
+ struct ioat_dca_priv *ioatdca = dca_priv(dca);
+ struct pci_dev *pdev;
+ int i;
+
+ /* This implementation only supports PCI-Express */
+ if (!dev_is_pci(dev))
+ return -ENODEV;
+ pdev = to_pci_dev(dev);
+
+ for (i = 0; i < ioatdca->max_requesters; i++) {
+ if (ioatdca->req_slots[i].pdev == pdev) {
+ writew(0, ioatdca->dca_base + (i * 4));
+ ioatdca->req_slots[i].pdev = NULL;
+ ioatdca->req_slots[i].rid = 0;
+ ioatdca->requester_count--;
+ return i;
+ }
+ }
+ return -ENODEV;
+}
+
+static u8 ioat_dca_get_tag(struct dca_provider *dca,
+ struct device *dev,
+ int cpu)
+{
+ struct ioat_dca_priv *ioatdca = dca_priv(dca);
+ int i, apic_id, bit, value;
+ u8 entry, tag;
+
+ tag = 0;
+ apic_id = cpu_physical_id(cpu);
+
+ for (i = 0; i < IOAT_TAG_MAP_LEN; i++) {
+ entry = ioatdca->tag_map[i];
+ if (entry & DCA_TAG_MAP_VALID) {
+ bit = entry & ~DCA_TAG_MAP_VALID;
+ value = (apic_id & (1 << bit)) ? 1 : 0;
+ } else {
+ value = entry ? 1 : 0;
+ }
+ tag |= (value << i);
+ }
+ return tag;
+}
+
+static int ioat_dca_dev_managed(struct dca_provider *dca,
+ struct device *dev)
+{
+ struct ioat_dca_priv *ioatdca = dca_priv(dca);
+ struct pci_dev *pdev;
+ int i;
+
+ pdev = to_pci_dev(dev);
+ for (i = 0; i < ioatdca->max_requesters; i++) {
+ if (ioatdca->req_slots[i].pdev == pdev)
+ return 1;
+ }
+ return 0;
+}
+
+static struct dca_ops ioat_dca_ops = {
+ .add_requester = ioat_dca_add_requester,
+ .remove_requester = ioat_dca_remove_requester,
+ .get_tag = ioat_dca_get_tag,
+ .dev_managed = ioat_dca_dev_managed,
+};
+
+
+struct dca_provider *ioat_dca_init(struct pci_dev *pdev, void __iomem *iobase)
+{
+ struct dca_provider *dca;
+ struct ioat_dca_priv *ioatdca;
+ u8 *tag_map = NULL;
+ int i;
+ int err;
+ u8 version;
+ u8 max_requesters;
+
+ if (!system_has_dca_enabled(pdev))
+ return NULL;
+
+ /* I/OAT v1 systems must have a known tag_map to support DCA */
+ switch (pdev->vendor) {
+ case PCI_VENDOR_ID_INTEL:
+ switch (pdev->device) {
+ case PCI_DEVICE_ID_INTEL_IOAT:
+ tag_map = ioat_tag_map_BNB;
+ break;
+ case PCI_DEVICE_ID_INTEL_IOAT_CNB:
+ tag_map = ioat_tag_map_CNB;
+ break;
+ case PCI_DEVICE_ID_INTEL_IOAT_SCNB:
+ tag_map = ioat_tag_map_SCNB;
+ break;
+ }
+ break;
+ case PCI_VENDOR_ID_UNISYS:
+ switch (pdev->device) {
+ case PCI_DEVICE_ID_UNISYS_DMA_DIRECTOR:
+ tag_map = ioat_tag_map_UNISYS;
+ break;
+ }
+ break;
+ }
+ if (tag_map == NULL)
+ return NULL;
+
+ version = readb(iobase + IOAT_VER_OFFSET);
+ if (version == IOAT_VER_3_0)
+ max_requesters = IOAT3_DCA_MAX_REQ;
+ else
+ max_requesters = IOAT_DCA_MAX_REQ;
+
+ dca = alloc_dca_provider(&ioat_dca_ops,
+ sizeof(*ioatdca) +
+ (sizeof(struct ioat_dca_slot) * max_requesters));
+ if (!dca)
+ return NULL;
+
+ ioatdca = dca_priv(dca);
+ ioatdca->max_requesters = max_requesters;
+ ioatdca->dca_base = iobase + 0x54;
+
+ /* copy over the APIC ID to DCA tag mapping */
+ for (i = 0; i < IOAT_TAG_MAP_LEN; i++)
+ ioatdca->tag_map[i] = tag_map[i];
+
+ err = register_dca_provider(dca, &pdev->dev);
+ if (err) {
+ free_dca_provider(dca);
+ return NULL;
+ }
+
+ 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_is_pci(dev))
+ 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_is_pci(dev))
+ 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,
+ struct device *dev,
+ int cpu)
+{
+ u8 tag;
+
+ tag = ioat_dca_get_tag(dca, dev, 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,
+ .dev_managed = ioat_dca_dev_managed,
+};
+
+static int ioat2_dca_count_dca_slots(void __iomem *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;
+ }
+
+ if (!dca2_tag_map_valid(ioatdca->tag_map)) {
+ WARN_TAINT_ONCE(1, TAINT_FIRMWARE_WORKAROUND,
+ "%s %s: APICID_TAG_MAP set incorrectly by BIOS, disabling DCA\n",
+ dev_driver_string(&pdev->dev),
+ dev_name(&pdev->dev));
+ free_dca_provider(dca);
+ return NULL;
+ }
+
+ err = register_dca_provider(dca, &pdev->dev);
+ if (err) {
+ free_dca_provider(dca);
+ return NULL;
+ }
+
+ return dca;
+}
+
+static int ioat3_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_is_pci(dev))
+ 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 + IOAT3_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 ioat3_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_is_pci(dev))
+ 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 + IOAT3_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 ioat3_dca_get_tag(struct dca_provider *dca,
+ struct device *dev,
+ int cpu)
+{
+ u8 tag;
+
+ struct ioat_dca_priv *ioatdca = dca_priv(dca);
+ int i, apic_id, bit, value;
+ u8 entry;
+
+ tag = 0;
+ apic_id = cpu_physical_id(cpu);
+
+ for (i = 0; i < IOAT_TAG_MAP_LEN; i++) {
+ entry = ioatdca->tag_map[i];
+ if (entry & DCA3_TAG_MAP_BIT_TO_SEL) {
+ bit = entry &
+ ~(DCA3_TAG_MAP_BIT_TO_SEL | DCA3_TAG_MAP_BIT_TO_INV);
+ value = (apic_id & (1 << bit)) ? 1 : 0;
+ } else if (entry & DCA3_TAG_MAP_BIT_TO_INV) {
+ bit = entry & ~DCA3_TAG_MAP_BIT_TO_INV;
+ value = (apic_id & (1 << bit)) ? 0 : 1;
+ } else {
+ value = (entry & DCA3_TAG_MAP_LITERAL_VAL) ? 1 : 0;
+ }
+ tag |= (value << i);
+ }
+
+ return tag;
+}
+
+static struct dca_ops ioat3_dca_ops = {
+ .add_requester = ioat3_dca_add_requester,
+ .remove_requester = ioat3_dca_remove_requester,
+ .get_tag = ioat3_dca_get_tag,
+ .dev_managed = ioat_dca_dev_managed,
+};
+
+static int ioat3_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 + IOAT3_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;
+}
+
+static inline int dca3_tag_map_invalid(u8 *tag_map)
+{
+ /*
+ * If the tag map is not programmed by the BIOS the default is:
+ * 0x80 0x80 0x80 0x80 0x80 0x00 0x00 0x00
+ *
+ * This an invalid map and will result in only 2 possible tags
+ * 0x1F and 0x00. 0x00 is an invalid DCA tag so we know that
+ * this entire definition is invalid.
+ */
+ return ((tag_map[0] == DCA_TAG_MAP_VALID) &&
+ (tag_map[1] == DCA_TAG_MAP_VALID) &&
+ (tag_map[2] == DCA_TAG_MAP_VALID) &&
+ (tag_map[3] == DCA_TAG_MAP_VALID) &&
+ (tag_map[4] == DCA_TAG_MAP_VALID));
+}
+
+struct dca_provider *ioat3_dca_init(struct pci_dev *pdev, void __iomem *iobase)
+{
+ struct dca_provider *dca;
+ struct ioat_dca_priv *ioatdca;
+ int slots;
+ int i;
+ int err;
+ u16 dca_offset;
+ u16 csi_fsb_control;
+ u16 pcie_control;
+ u8 bit;
+
+ union {
+ u64 full;
+ struct {
+ u32 low;
+ u32 high;
+ };
+ } tag_map;
+
+ if (!system_has_dca_enabled(pdev))
+ return NULL;
+
+ dca_offset = readw(iobase + IOAT_DCAOFFSET_OFFSET);
+ if (dca_offset == 0)
+ return NULL;
+
+ slots = ioat3_dca_count_dca_slots(iobase, dca_offset);
+ if (slots == 0)
+ return NULL;
+
+ dca = alloc_dca_provider(&ioat3_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 + IOAT3_CSI_CONTROL_OFFSET);
+ if ((csi_fsb_control & IOAT3_CSI_CONTROL_PREFETCH) == 0) {
+ csi_fsb_control |= IOAT3_CSI_CONTROL_PREFETCH;
+ writew(csi_fsb_control,
+ ioatdca->dca_base + IOAT3_CSI_CONTROL_OFFSET);
+ }
+ pcie_control = readw(ioatdca->dca_base + IOAT3_PCI_CONTROL_OFFSET);
+ if ((pcie_control & IOAT3_PCI_CONTROL_MEMWR) == 0) {
+ pcie_control |= IOAT3_PCI_CONTROL_MEMWR;
+ writew(pcie_control,
+ ioatdca->dca_base + IOAT3_PCI_CONTROL_OFFSET);
+ }
+
+
+ /* TODO version, compatibility and configuration checks */
+
+ /* copy out the APIC to DCA tag map */
+ tag_map.low =
+ readl(ioatdca->dca_base + IOAT3_APICID_TAG_MAP_OFFSET_LOW);
+ tag_map.high =
+ readl(ioatdca->dca_base + IOAT3_APICID_TAG_MAP_OFFSET_HIGH);
+ for (i = 0; i < 8; i++) {
+ bit = tag_map.full >> (8 * i);
+ ioatdca->tag_map[i] = bit & DCA_TAG_MAP_MASK;
+ }
+
+ if (dca3_tag_map_invalid(ioatdca->tag_map)) {
+ WARN_TAINT_ONCE(1, TAINT_FIRMWARE_WORKAROUND,
+ "%s %s: APICID_TAG_MAP set incorrectly by BIOS, disabling DCA\n",
+ dev_driver_string(&pdev->dev),
+ dev_name(&pdev->dev));
+ free_dca_provider(dca);
+ return NULL;
+ }
+
+ err = register_dca_provider(dca, &pdev->dev);
+ if (err) {
+ free_dca_provider(dca);
+ return NULL;
+ }
+
+ return dca;
+}
Code Review / kvmfornfv.git / blobdiff