[PATCH v6 4/6] vfio/nvgrace-gpu: split the code to wait for GPU ready

[<ankita@nvidia.com>]

From: Ankit Agrawal <ankita@nvidia.com>

Split the function that check for the GPU device being ready on
the probe.

Move the code to wait for the GPU to be ready through BAR0 register
reads to a separate function. This would help reuse the code.

Reviewed-by: Shameer Kolothum <skolothumtho@nvidia.com>
Signed-off-by: Ankit Agrawal <ankita@nvidia.com>
---
 drivers/vfio/pci/nvgrace-gpu/main.c | 29 +++++++++++++++++------------
 1 file changed, 17 insertions(+), 12 deletions(-)

diff --git a/drivers/vfio/pci/nvgrace-gpu/main.c b/drivers/vfio/pci/nvgrace-gpu/main.c
index 8a982310b188..2b736cb82f38 100644
--- a/drivers/vfio/pci/nvgrace-gpu/main.c
+++ b/drivers/vfio/pci/nvgrace-gpu/main.c
@@ -130,6 +130,20 @@ static void nvgrace_gpu_close_device(struct vfio_device *core_vdev)
 	vfio_pci_core_close_device(core_vdev);
 }
 
+static int nvgrace_gpu_wait_device_ready(void __iomem *io)
+{
+	unsigned long timeout = jiffies + msecs_to_jiffies(POLL_TIMEOUT_MS);
+
+	do {
+		if ((ioread32(io + C2C_LINK_BAR0_OFFSET) == STATUS_READY) &&
+		    (ioread32(io + HBM_TRAINING_BAR0_OFFSET) == STATUS_READY))
+			return 0;
+		msleep(POLL_QUANTUM_MS);
+	} while (!time_after(jiffies, timeout));
+
+	return -ETIME;
+}
+
 static unsigned long addr_to_pgoff(struct vm_area_struct *vma,
 				   unsigned long addr)
 {
@@ -933,9 +947,8 @@ static bool nvgrace_gpu_has_mig_hw_bug(struct pci_dev *pdev)
  * Ensure that the BAR0 region is enabled before accessing the
  * registers.
  */
-static int nvgrace_gpu_wait_device_ready(struct pci_dev *pdev)
+static int nvgrace_gpu_probe_check_device_ready(struct pci_dev *pdev)
 {
-	unsigned long timeout = jiffies + msecs_to_jiffies(POLL_TIMEOUT_MS);
 	void __iomem *io;
 	int ret = -ETIME;
 
@@ -953,16 +966,8 @@ static int nvgrace_gpu_wait_device_ready(struct pci_dev *pdev)
 		goto iomap_exit;
 	}
 
-	do {
-		if ((ioread32(io + C2C_LINK_BAR0_OFFSET) == STATUS_READY) &&
-		    (ioread32(io + HBM_TRAINING_BAR0_OFFSET) == STATUS_READY)) {
-			ret = 0;
-			goto reg_check_exit;
-		}
-		msleep(POLL_QUANTUM_MS);
-	} while (!time_after(jiffies, timeout));
+	ret = nvgrace_gpu_wait_device_ready(io);
 
-reg_check_exit:
 	pci_iounmap(pdev, io);
 iomap_exit:
 	pci_release_selected_regions(pdev, 1 << 0);
@@ -979,7 +984,7 @@ static int nvgrace_gpu_probe(struct pci_dev *pdev,
 	u64 memphys, memlength;
 	int ret;
 
-	ret = nvgrace_gpu_wait_device_ready(pdev);
+	ret = nvgrace_gpu_probe_check_device_ready(pdev);
 	if (ret)
 		return ret;
 
-- 
2.34.1