1 files changed, 157 insertions, 0 deletions
diff --git a/drivers/dma/amd/ae4dma/ae4dma-dev.c b/drivers/dma/amd/ae4dma/ae4dma-dev.c
new file mode 100644
index 000000000000..8de3bef41b58
--- /dev/null
+++ b/drivers/dma/amd/ae4dma/ae4dma-dev.c
@@ -0,0 +1,157 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * AMD AE4DMA driver
+ *
+ * Copyright (c) 2024, Advanced Micro Devices, Inc.
+ * All Rights Reserved.
+ *
+ * Author: Basavaraj Natikar <Basavaraj.Natikar@amd.com>
+ */
+
+#include "ae4dma.h"
+
+static unsigned int max_hw_q = 1;
+module_param(max_hw_q, uint, 0444);
+MODULE_PARM_DESC(max_hw_q, "max hw queues supported by engine (any non-zero value, default: 1)");
+
+static void ae4_pending_work(struct work_struct *work)
+{
+	struct ae4_cmd_queue *ae4cmd_q = container_of(work, struct ae4_cmd_queue, p_work.work);
+	struct pt_cmd_queue *cmd_q = &ae4cmd_q->cmd_q;
+	struct pt_cmd *cmd;
+	u32 cridx;
+
+	for (;;) {
+		wait_event_interruptible(ae4cmd_q->q_w,
+					 ((atomic64_read(&ae4cmd_q->done_cnt)) <
+					   atomic64_read(&ae4cmd_q->intr_cnt)));
+
+		atomic64_inc(&ae4cmd_q->done_cnt);
+
+		mutex_lock(&ae4cmd_q->cmd_lock);
+		cridx = readl(cmd_q->reg_control + AE4_RD_IDX_OFF);
+		while ((ae4cmd_q->dridx != cridx) && !list_empty(&ae4cmd_q->cmd)) {
+			cmd = list_first_entry(&ae4cmd_q->cmd, struct pt_cmd, entry);
+			list_del(&cmd->entry);
+
+			ae4_check_status_error(ae4cmd_q, ae4cmd_q->dridx);
+			cmd->pt_cmd_callback(cmd->data, cmd->ret);
+
+			ae4cmd_q->q_cmd_count--;
+			ae4cmd_q->dridx = (ae4cmd_q->dridx + 1) % CMD_Q_LEN;
+
+			complete_all(&ae4cmd_q->cmp);
+		}
+		mutex_unlock(&ae4cmd_q->cmd_lock);
+	}
+}
+
+static irqreturn_t ae4_core_irq_handler(int irq, void *data)
+{
+	struct ae4_cmd_queue *ae4cmd_q = data;
+	struct pt_cmd_queue *cmd_q;
+	struct pt_device *pt;
+	u32 status;
+
+	cmd_q = &ae4cmd_q->cmd_q;
+	pt = cmd_q->pt;
+
+	pt->total_interrupts++;
+	atomic64_inc(&ae4cmd_q->intr_cnt);
+
+	status = readl(cmd_q->reg_control + AE4_INTR_STS_OFF);
+	if (status & BIT(0)) {
+		status &= GENMASK(31, 1);
+		writel(status, cmd_q->reg_control + AE4_INTR_STS_OFF);
+	}
+
+	wake_up(&ae4cmd_q->q_w);
+
+	return IRQ_HANDLED;
+}
+
+void ae4_destroy_work(struct ae4_device *ae4)
+{
+	struct ae4_cmd_queue *ae4cmd_q;
+	int i;
+
+	for (i = 0; i < ae4->cmd_q_count; i++) {
+		ae4cmd_q = &ae4->ae4cmd_q[i];
+
+		if (!ae4cmd_q->pws)
+			break;
+
+		cancel_delayed_work_sync(&ae4cmd_q->p_work);
+		destroy_workqueue(ae4cmd_q->pws);
+	}
+}
+
+int ae4_core_init(struct ae4_device *ae4)
+{
+	struct pt_device *pt = &ae4->pt;
+	struct ae4_cmd_queue *ae4cmd_q;
+	struct device *dev = pt->dev;
+	struct pt_cmd_queue *cmd_q;
+	int i, ret = 0;
+
+	writel(max_hw_q, pt->io_regs);
+
+	for (i = 0; i < max_hw_q; i++) {
+		ae4cmd_q = &ae4->ae4cmd_q[i];
+		ae4cmd_q->id = ae4->cmd_q_count;
+		ae4->cmd_q_count++;
+
+		cmd_q = &ae4cmd_q->cmd_q;
+		cmd_q->pt = pt;
+
+		cmd_q->reg_control = pt->io_regs + ((i + 1) * AE4_Q_SZ);
+
+		ret = devm_request_irq(dev, ae4->ae4_irq[i], ae4_core_irq_handler, 0,
+				       dev_name(pt->dev), ae4cmd_q);
+		if (ret)
+			return ret;
+
+		cmd_q->qsize = Q_SIZE(sizeof(struct ae4dma_desc));
+
+		cmd_q->qbase = dmam_alloc_coherent(dev, cmd_q->qsize, &cmd_q->qbase_dma,
+						   GFP_KERNEL);
+		if (!cmd_q->qbase)
+			return -ENOMEM;
+	}
+
+	for (i = 0; i < ae4->cmd_q_count; i++) {
+		ae4cmd_q = &ae4->ae4cmd_q[i];
+
+		cmd_q = &ae4cmd_q->cmd_q;
+
+		cmd_q->reg_control = pt->io_regs + ((i + 1) * AE4_Q_SZ);
+
+		/* Update the device registers with queue information. */
+		writel(CMD_Q_LEN, cmd_q->reg_control + AE4_MAX_IDX_OFF);
+
+		cmd_q->qdma_tail = cmd_q->qbase_dma;
+		writel(lower_32_bits(cmd_q->qdma_tail), cmd_q->reg_control + AE4_Q_BASE_L_OFF);
+		writel(upper_32_bits(cmd_q->qdma_tail), cmd_q->reg_control + AE4_Q_BASE_H_OFF);
+
+		INIT_LIST_HEAD(&ae4cmd_q->cmd);
+		init_waitqueue_head(&ae4cmd_q->q_w);
+
+		ae4cmd_q->pws = alloc_ordered_workqueue("ae4dma_%d", WQ_MEM_RECLAIM, ae4cmd_q->id);
+		if (!ae4cmd_q->pws) {
+			ae4_destroy_work(ae4);
+			return -ENOMEM;
+		}
+		INIT_DELAYED_WORK(&ae4cmd_q->p_work, ae4_pending_work);
+		queue_delayed_work(ae4cmd_q->pws, &ae4cmd_q->p_work,  usecs_to_jiffies(100));
+
+		init_completion(&ae4cmd_q->cmp);
+	}
+
+	ret = pt_dmaengine_register(pt);
+	if (ret)
+		ae4_destroy_work(ae4);
+	else
+		ptdma_debugfs_setup(pt);
+
+	return ret;
+}