I/OAT: I/OAT version 3.0 support
This patch adds to ioatdma and dca modules
support for Intel I/OAT DMA engine ver.3 (aka CB3 device).
The main features of I/OAT ver.3 are:
* 8 single channel DMA devices (8 channels total)
* 8 DCA providers, each can accept 2 requesters
* 8-bit TAG values and 32-bit extended APIC IDs
Signed-off-by: Maciej Sosnowski <maciej.sosnowski@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
diff --git a/drivers/dma/ioat_dca.c b/drivers/dma/ioat_dca.c
index 9e92276..6cf622d 100644
--- a/drivers/dma/ioat_dca.c
+++ b/drivers/dma/ioat_dca.c
@@ -37,12 +37,18 @@
#include "ioatdma_registers.h"
/*
- * Bit 16 of a tag map entry is the "valid" bit, if it is set then bits 0:15
+ * 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
+
/*
* "Legacy" DCA systems do not implement the DCA register set in the
* I/OAT device. Software needs direct support for their tag mappings.
@@ -95,6 +101,7 @@
};
#define IOAT_DCA_MAX_REQ 6
+#define IOAT3_DCA_MAX_REQ 2
struct ioat_dca_priv {
void __iomem *iobase;
@@ -171,7 +178,9 @@
return -ENODEV;
}
-static u8 ioat_dca_get_tag(struct dca_provider *dca, int cpu)
+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;
@@ -193,10 +202,26 @@
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,
};
@@ -207,6 +232,8 @@
u8 *tag_map = NULL;
int i;
int err;
+ u8 version;
+ u8 max_requesters;
if (!system_has_dca_enabled(pdev))
return NULL;
@@ -237,15 +264,20 @@
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) * IOAT_DCA_MAX_REQ));
+ (sizeof(struct ioat_dca_slot) * max_requesters));
if (!dca)
return NULL;
ioatdca = dca_priv(dca);
- ioatdca->max_requesters = IOAT_DCA_MAX_REQ;
-
+ ioatdca->max_requesters = max_requesters;
ioatdca->dca_base = iobase + 0x54;
/* copy over the APIC ID to DCA tag mapping */
@@ -323,11 +355,13 @@
return -ENODEV;
}
-static u8 ioat2_dca_get_tag(struct dca_provider *dca, int cpu)
+static u8 ioat2_dca_get_tag(struct dca_provider *dca,
+ struct device *dev,
+ int cpu)
{
u8 tag;
- tag = ioat_dca_get_tag(dca, cpu);
+ tag = ioat_dca_get_tag(dca, dev, cpu);
tag = (~tag) & 0x1F;
return tag;
}
@@ -336,6 +370,7 @@
.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)
@@ -425,3 +460,198 @@
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->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 + 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->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 + 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;
+}
+
+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;
+ }
+
+ err = register_dca_provider(dca, &pdev->dev);
+ if (err) {
+ free_dca_provider(dca);
+ return NULL;
+ }
+
+ return dca;
+}