RDMA/ionic: Create device queues to support admin operations

Setup RDMA admin queues using device command exposed over
auxiliary device and manage these queues using ida.

Co-developed-by: Andrew Boyer <andrew.boyer@amd.com>
Signed-off-by: Andrew Boyer <andrew.boyer@amd.com>
Co-developed-by: Allen Hubbe <allen.hubbe@amd.com>
Signed-off-by: Allen Hubbe <allen.hubbe@amd.com>
Signed-off-by: Abhijit Gangurde <abhijit.gangurde@amd.com>
Link: https://patch.msgid.link/20250903061606.4139957-10-abhijit.gangurde@amd.com
Signed-off-by: Leon Romanovsky <leon@kernel.org>

1 files changed, 52 insertions, 0 deletions

diff --git a/drivers/infiniband/hw/ionic/ionic_queue.c b/drivers/infiniband/hw/ionic/ionic_queue.c
new file mode 100644
index 000000000000..aa897ed2a412
--- /dev/null
+++ b/drivers/infiniband/hw/ionic/ionic_queue.c
@@ -0,0 +1,52 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (C) 2018-2025, Advanced Micro Devices, Inc. */
+
+#include <linux/dma-mapping.h>
+
+#include "ionic_queue.h"
+
+int ionic_queue_init(struct ionic_queue *q, struct device *dma_dev,
+		     int depth, size_t stride)
+{
+	if (depth < 0 || depth > 0xffff)
+		return -EINVAL;
+
+	if (stride == 0 || stride > 0x10000)
+		return -EINVAL;
+
+	if (depth == 0)
+		depth = 1;
+
+	q->depth_log2 = order_base_2(depth + 1);
+	q->stride_log2 = order_base_2(stride);
+
+	if (q->depth_log2 + q->stride_log2 < PAGE_SHIFT)
+		q->depth_log2 = PAGE_SHIFT - q->stride_log2;
+
+	if (q->depth_log2 > 16 || q->stride_log2 > 16)
+		return -EINVAL;
+
+	q->size = BIT_ULL(q->depth_log2 + q->stride_log2);
+	q->mask = BIT(q->depth_log2) - 1;
+
+	q->ptr = dma_alloc_coherent(dma_dev, q->size, &q->dma, GFP_KERNEL);
+	if (!q->ptr)
+		return -ENOMEM;
+
+	/* it will always be page aligned, but just to be sure... */
+	if (!PAGE_ALIGNED(q->ptr)) {
+		dma_free_coherent(dma_dev, q->size, q->ptr, q->dma);
+		return -ENOMEM;
+	}
+
+	q->prod = 0;
+	q->cons = 0;
+	q->dbell = 0;
+
+	return 0;
+}
+
+void ionic_queue_destroy(struct ionic_queue *q, struct device *dma_dev)
+{
+	dma_free_coherent(dma_dev, q->size, q->ptr, q->dma);
+}