ioat2,3: put channel hardware in known state at init

Put the ioat2 and ioat3 state machines in the halted state with all
errors cleared.

The ioat1 init path is not disturbed for stability, there are no
reported ioat1 initiaization issues.

Cc: <stable@kernel.org>
Reported-by: Roland Dreier <rdreier@cisco.com>
Tested-by: Roland Dreier <rdreier@cisco.com>
Acked-by: Simon Horman <horms@verge.net.au>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

1 files changed, 18 insertions, 0 deletions

diff --git a/drivers/dma/ioat/dma.h b/drivers/dma/ioat/dma.h
index 45edde996480..bbc3e78ef333 100644
--- a/drivers/dma/ioat/dma.h
+++ b/drivers/dma/ioat/dma.h
@@ -60,6 +60,7 @@
  * @dca: direct cache access context
  * @intr_quirk: interrupt setup quirk (for ioat_v1 devices)
  * @enumerate_channels: hw version specific channel enumeration
+ * @reset_hw: hw version specific channel (re)initialization
  * @cleanup_tasklet: select between the v2 and v3 cleanup routines
  * @timer_fn: select between the v2 and v3 timer watchdog routines
  * @self_test: hardware version specific self test for each supported op type
@@ -78,6 +79,7 @@ struct ioatdma_device {
         struct dca_provider *dca;
         void (*intr_quirk)(struct ioatdma_device *device);
         int (*enumerate_channels)(struct ioatdma_device *device);
+        int (*reset_hw)(struct ioat_chan_common *chan);
         void (*cleanup_tasklet)(unsigned long data);
         void (*timer_fn)(unsigned long data);
         int (*self_test)(struct ioatdma_device *device);
@@ -264,6 +266,22 @@ static inline void ioat_suspend(struct ioat_chan_common *chan)
         writeb(IOAT_CHANCMD_SUSPEND, chan->reg_base + IOAT_CHANCMD_OFFSET(ver));
 }
 
+static inline void ioat_reset(struct ioat_chan_common *chan)
+{
+        u8 ver = chan->device->version;
+
+        writeb(IOAT_CHANCMD_RESET, chan->reg_base + IOAT_CHANCMD_OFFSET(ver));
+}
+
+static inline bool ioat_reset_pending(struct ioat_chan_common *chan)
+{
+        u8 ver = chan->device->version;
+        u8 cmd;
+
+        cmd = readb(chan->reg_base + IOAT_CHANCMD_OFFSET(ver));
+        return (cmd & IOAT_CHANCMD_RESET) == IOAT_CHANCMD_RESET;
+}
+
 static inline void ioat_set_chainaddr(struct ioat_dma_chan *ioat, u64 addr)
 {
         struct ioat_chan_common *chan = &ioat->base;