Merge branch 'topic/ioat' into for-linus
diff --git a/Documentation/ABI/stable/sysfs-driver-dma-ioatdma b/Documentation/ABI/stable/sysfs-driver-dma-ioatdma
new file mode 100644
index 0000000..420c1d0
--- /dev/null
+++ b/Documentation/ABI/stable/sysfs-driver-dma-ioatdma
@@ -0,0 +1,30 @@
+What: sys/devices/pciXXXX:XX/0000:XX:XX.X/dma/dma<n>chan<n>/quickdata/cap
+Date: December 3, 2009
+KernelVersion: 2.6.32
+Contact: dmaengine@vger.kernel.org
+Description: Capabilities the DMA supports.Currently there are DMA_PQ, DMA_PQ_VAL,
+ DMA_XOR,DMA_XOR_VAL,DMA_INTERRUPT.
+
+What: sys/devices/pciXXXX:XX/0000:XX:XX.X/dma/dma<n>chan<n>/quickdata/ring_active
+Date: December 3, 2009
+KernelVersion: 2.6.32
+Contact: dmaengine@vger.kernel.org
+Description: The number of descriptors active in the ring.
+
+What: sys/devices/pciXXXX:XX/0000:XX:XX.X/dma/dma<n>chan<n>/quickdata/ring_size
+Date: December 3, 2009
+KernelVersion: 2.6.32
+Contact: dmaengine@vger.kernel.org
+Description: Descriptor ring size, total number of descriptors available.
+
+What: sys/devices/pciXXXX:XX/0000:XX:XX.X/dma/dma<n>chan<n>/quickdata/version
+Date: December 3, 2009
+KernelVersion: 2.6.32
+Contact: dmaengine@vger.kernel.org
+Description: Version of ioatdma device.
+
+What: sys/devices/pciXXXX:XX/0000:XX:XX.X/dma/dma<n>chan<n>/quickdata/intr_coalesce
+Date: August 8, 2017
+KernelVersion: 4.14
+Contact: dmaengine@vger.kernel.org
+Description: Tune-able interrupt delay value per channel basis.
diff --git a/drivers/dma/ioat/dma.c b/drivers/dma/ioat/dma.c
index a371b07..f70cc74 100644
--- a/drivers/dma/ioat/dma.c
+++ b/drivers/dma/ioat/dma.c
@@ -644,9 +644,13 @@ static void __cleanup(struct ioatdma_chan *ioat_chan, dma_addr_t phys_complete)
mod_timer(&ioat_chan->timer, jiffies + IDLE_TIMEOUT);
}
- /* 5 microsecond delay per pending descriptor */
- writew(min((5 * (active - i)), IOAT_INTRDELAY_MASK),
- ioat_chan->ioat_dma->reg_base + IOAT_INTRDELAY_OFFSET);
+ /* microsecond delay by sysfs variable per pending descriptor */
+ if (ioat_chan->intr_coalesce != ioat_chan->prev_intr_coalesce) {
+ writew(min((ioat_chan->intr_coalesce * (active - i)),
+ IOAT_INTRDELAY_MASK),
+ ioat_chan->ioat_dma->reg_base + IOAT_INTRDELAY_OFFSET);
+ ioat_chan->prev_intr_coalesce = ioat_chan->intr_coalesce;
+ }
}
static void ioat_cleanup(struct ioatdma_chan *ioat_chan)
diff --git a/drivers/dma/ioat/dma.h b/drivers/dma/ioat/dma.h
index a9bc1a1..56200ee 100644
--- a/drivers/dma/ioat/dma.h
+++ b/drivers/dma/ioat/dma.h
@@ -142,11 +142,14 @@ struct ioatdma_chan {
spinlock_t prep_lock;
struct ioat_descs descs[2];
int desc_chunks;
+ int intr_coalesce;
+ int prev_intr_coalesce;
};
struct ioat_sysfs_entry {
struct attribute attr;
ssize_t (*show)(struct dma_chan *, char *);
+ ssize_t (*store)(struct dma_chan *, const char *, size_t);
};
/**
diff --git a/drivers/dma/ioat/init.c b/drivers/dma/ioat/init.c
index ed8ed11..93e006c 100644
--- a/drivers/dma/ioat/init.c
+++ b/drivers/dma/ioat/init.c
@@ -39,7 +39,7 @@ MODULE_VERSION(IOAT_DMA_VERSION);
MODULE_LICENSE("Dual BSD/GPL");
MODULE_AUTHOR("Intel Corporation");
-static struct pci_device_id ioat_pci_tbl[] = {
+static const struct pci_device_id ioat_pci_tbl[] = {
/* I/OAT v3 platforms */
{ PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_IOAT_TBG0) },
{ PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_IOAT_TBG1) },
diff --git a/drivers/dma/ioat/sysfs.c b/drivers/dma/ioat/sysfs.c
index cb4a857..3ac677f 100644
--- a/drivers/dma/ioat/sysfs.c
+++ b/drivers/dma/ioat/sysfs.c
@@ -64,8 +64,24 @@ ioat_attr_show(struct kobject *kobj, struct attribute *attr, char *page)
return entry->show(&ioat_chan->dma_chan, page);
}
+static ssize_t
+ioat_attr_store(struct kobject *kobj, struct attribute *attr,
+const char *page, size_t count)
+{
+ struct ioat_sysfs_entry *entry;
+ struct ioatdma_chan *ioat_chan;
+
+ entry = container_of(attr, struct ioat_sysfs_entry, attr);
+ ioat_chan = container_of(kobj, struct ioatdma_chan, kobj);
+
+ if (!entry->store)
+ return -EIO;
+ return entry->store(&ioat_chan->dma_chan, page, count);
+}
+
const struct sysfs_ops ioat_sysfs_ops = {
.show = ioat_attr_show,
+ .store = ioat_attr_store,
};
void ioat_kobject_add(struct ioatdma_device *ioat_dma, struct kobj_type *type)
@@ -121,11 +137,37 @@ static ssize_t ring_active_show(struct dma_chan *c, char *page)
}
static struct ioat_sysfs_entry ring_active_attr = __ATTR_RO(ring_active);
+static ssize_t intr_coalesce_show(struct dma_chan *c, char *page)
+{
+ struct ioatdma_chan *ioat_chan = to_ioat_chan(c);
+
+ return sprintf(page, "%d\n", ioat_chan->intr_coalesce);
+}
+
+static ssize_t intr_coalesce_store(struct dma_chan *c, const char *page,
+size_t count)
+{
+ int intr_coalesce = 0;
+ struct ioatdma_chan *ioat_chan = to_ioat_chan(c);
+
+ if (sscanf(page, "%du", &intr_coalesce) != -1) {
+ if ((intr_coalesce < 0) ||
+ (intr_coalesce > IOAT_INTRDELAY_MASK))
+ return -EINVAL;
+ ioat_chan->intr_coalesce = intr_coalesce;
+ }
+
+ return count;
+}
+
+static struct ioat_sysfs_entry intr_coalesce_attr = __ATTR_RW(intr_coalesce);
+
static struct attribute *ioat_attrs[] = {
&ring_size_attr.attr,
&ring_active_attr.attr,
&ioat_cap_attr.attr,
&ioat_version_attr.attr,
+ &intr_coalesce_attr.attr,
NULL,
};
