accel/ivpu: Add IPC driver and JSM messages

The IPC driver is used to send and receive messages to/from firmware
running on the VPU.

The only supported IPC message format is Job Submission Model (JSM)
defined in vpu_jsm_api.h header.

Co-developed-by: Andrzej Kacprowski <andrzej.kacprowski@linux.intel.com>
Signed-off-by: Andrzej Kacprowski <andrzej.kacprowski@linux.intel.com>
Co-developed-by: Krystian Pradzynski <krystian.pradzynski@linux.intel.com>
Signed-off-by: Krystian Pradzynski <krystian.pradzynski@linux.intel.com>
Signed-off-by: Jacek Lawrynowicz <jacek.lawrynowicz@linux.intel.com>
Reviewed-by: Oded Gabbay <ogabbay@kernel.org>
Reviewed-by: Jeffrey Hugo <quic_jhugo@quicinc.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20230117092723.60441-5-jacek.lawrynowicz@linux.intel.com

drivers/accel/ivpu/Makefile

@@ -5,6 +5,8 @@ intel_vpu-y := \
 	ivpu_drv.o \
 	ivpu_gem.o \
 	ivpu_hw_mtl.o \
+	ivpu_ipc.o \
+	ivpu_jsm_msg.o \
 	ivpu_mmu.o \
 	ivpu_mmu_context.o
 

drivers/accel/ivpu/ivpu_drv.c

@@ -17,6 +17,7 @@
 #include "ivpu_drv.h"
 #include "ivpu_gem.h"
 #include "ivpu_hw.h"
+#include "ivpu_ipc.h"
 #include "ivpu_mmu.h"
 #include "ivpu_mmu_context.h"
 
@@ -229,6 +230,7 @@ int ivpu_shutdown(struct ivpu_device *vdev)
 	int ret;
 
 	ivpu_hw_irq_disable(vdev);
+	ivpu_ipc_disable(vdev);
 	ivpu_mmu_disable(vdev);
 
 	ret = ivpu_hw_power_down(vdev);
@@ -339,6 +341,10 @@ static int ivpu_dev_init(struct ivpu_device *vdev)
 	if (!vdev->mmu)
 		return -ENOMEM;
 
+	vdev->ipc = drmm_kzalloc(&vdev->drm, sizeof(*vdev->ipc), GFP_KERNEL);
+	if (!vdev->ipc)
+		return -ENOMEM;
+
 	vdev->hw->ops = &ivpu_hw_mtl_ops;
 	vdev->platform = IVPU_PLATFORM_INVALID;
 	vdev->context_xa_limit.min = IVPU_GLOBAL_CONTEXT_MMU_SSID + 1;
@@ -383,6 +389,12 @@ static int ivpu_dev_init(struct ivpu_device *vdev)
 		goto err_mmu_gctx_fini;
 	}
 
+	ret = ivpu_ipc_init(vdev);
+	if (ret) {
+		ivpu_err(vdev, "Failed to initialize IPC: %d\n", ret);
+		goto err_mmu_gctx_fini;
+	}
+
 	return 0;
 
 err_mmu_gctx_fini:
@@ -397,6 +409,7 @@ err_xa_destroy:
 static void ivpu_dev_fini(struct ivpu_device *vdev)
 {
 	ivpu_shutdown(vdev);
+	ivpu_ipc_fini(vdev);
 	ivpu_mmu_global_context_fini(vdev);
 
 	drm_WARN_ON(&vdev->drm, !xa_empty(&vdev->context_xa));

drivers/accel/ivpu/ivpu_drv.h

@@ -74,6 +74,7 @@ struct ivpu_wa_table {
 
 struct ivpu_hw_info;
 struct ivpu_mmu_info;
+struct ivpu_ipc_info;
 
 struct ivpu_device {
 	struct drm_device drm;
@@ -85,6 +86,7 @@ struct ivpu_device {
 	struct ivpu_wa_table wa;
 	struct ivpu_hw_info *hw;
 	struct ivpu_mmu_info *mmu;
+	struct ivpu_ipc_info *ipc;
 
 	struct ivpu_mmu_context gctx;
 	struct xarray context_xa;

drivers/accel/ivpu/ivpu_hw_mtl.c

@@ -7,6 +7,7 @@
 #include "ivpu_hw_mtl_reg.h"
 #include "ivpu_hw_reg_io.h"
 #include "ivpu_hw.h"
+#include "ivpu_ipc.h"
 #include "ivpu_mmu.h"
 
 #define TILE_FUSE_ENABLE_BOTH	     0x0
@@ -934,6 +935,9 @@ static u32 ivpu_hw_mtl_irqv_handler(struct ivpu_device *vdev, int irq)
 	if (REG_TEST_FLD(MTL_VPU_HOST_SS_ICB_STATUS_0, MMU_IRQ_0_INT, status))
 		ivpu_mmu_irq_evtq_handler(vdev);
 
+	if (REG_TEST_FLD(MTL_VPU_HOST_SS_ICB_STATUS_0, HOST_IPC_FIFO_INT, status))
+		ivpu_ipc_irq_handler(vdev);
+
 	if (REG_TEST_FLD(MTL_VPU_HOST_SS_ICB_STATUS_0, MMU_IRQ_1_INT, status))
 		ivpu_dbg(vdev, IRQ, "MMU sync complete\n");
 

drivers/accel/ivpu/ivpu_ipc.c

+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2020-2023 Intel Corporation
+ */
+
+#include <linux/genalloc.h>
+#include <linux/highmem.h>
+#include <linux/kthread.h>
+#include <linux/wait.h>
+
+#include "ivpu_drv.h"
+#include "ivpu_gem.h"
+#include "ivpu_hw.h"
+#include "ivpu_hw_reg_io.h"
+#include "ivpu_ipc.h"
+#include "ivpu_jsm_msg.h"
+
+#define IPC_MAX_RX_MSG	128
+#define IS_KTHREAD()	(get_current()->flags & PF_KTHREAD)
+
+struct ivpu_ipc_tx_buf {
+	struct ivpu_ipc_hdr ipc;
+	struct vpu_jsm_msg jsm;
+};
+
+struct ivpu_ipc_rx_msg {
+	struct list_head link;
+	struct ivpu_ipc_hdr *ipc_hdr;
+	struct vpu_jsm_msg *jsm_msg;
+};
+
+static void ivpu_ipc_msg_dump(struct ivpu_device *vdev, char *c,
+			      struct ivpu_ipc_hdr *ipc_hdr, u32 vpu_addr)
+{
+	ivpu_dbg(vdev, IPC,
+		 "%s: vpu:0x%x (data_addr:0x%08x, data_size:0x%x, channel:0x%x, src_node:0x%x, dst_node:0x%x, status:0x%x)",
+		 c, vpu_addr, ipc_hdr->data_addr, ipc_hdr->data_size, ipc_hdr->channel,
+		 ipc_hdr->src_node, ipc_hdr->dst_node, ipc_hdr->status);
+}
+
+static void ivpu_jsm_msg_dump(struct ivpu_device *vdev, char *c,
+			      struct vpu_jsm_msg *jsm_msg, u32 vpu_addr)
+{
+	u32 *payload = (u32 *)&jsm_msg->payload;
+
+	ivpu_dbg(vdev, JSM,
+		 "%s: vpu:0x%08x (type:0x%x, status:0x%x, id: 0x%x, result: 0x%x, payload:0x%x 0x%x 0x%x 0x%x 0x%x)\n",
+		 c, vpu_addr, jsm_msg->type, jsm_msg->status, jsm_msg->request_id, jsm_msg->result,
+		 payload[0], payload[1], payload[2], payload[3], payload[4]);
+}
+
+static void
+ivpu_ipc_rx_mark_free(struct ivpu_device *vdev, struct ivpu_ipc_hdr *ipc_hdr,
+		      struct vpu_jsm_msg *jsm_msg)
+{
+	ipc_hdr->status = IVPU_IPC_HDR_FREE;
+	if (jsm_msg)
+		jsm_msg->status = VPU_JSM_MSG_FREE;
+	wmb(); /* Flush WC buffers for message statuses */
+}
+
+static void ivpu_ipc_mem_fini(struct ivpu_device *vdev)
+{
+	struct ivpu_ipc_info *ipc = vdev->ipc;
+
+	ivpu_bo_free_internal(ipc->mem_rx);
+	ivpu_bo_free_internal(ipc->mem_tx);
+}
+
+static int
+ivpu_ipc_tx_prepare(struct ivpu_device *vdev, struct ivpu_ipc_consumer *cons,
+		    struct vpu_jsm_msg *req)
+{
+	struct ivpu_ipc_info *ipc = vdev->ipc;
+	struct ivpu_ipc_tx_buf *tx_buf;
+	u32 tx_buf_vpu_addr;
+	u32 jsm_vpu_addr;
+
+	tx_buf_vpu_addr = gen_pool_alloc(ipc->mm_tx, sizeof(*tx_buf));
+	if (!tx_buf_vpu_addr) {
+		ivpu_err(vdev, "Failed to reserve IPC buffer, size %ld\n",
+			 sizeof(*tx_buf));
+		return -ENOMEM;
+	}
+
+	tx_buf = ivpu_to_cpu_addr(ipc->mem_tx, tx_buf_vpu_addr);
+	if (drm_WARN_ON(&vdev->drm, !tx_buf)) {
+		gen_pool_free(ipc->mm_tx, tx_buf_vpu_addr, sizeof(*tx_buf));
+		return -EIO;
+	}
+
+	jsm_vpu_addr = tx_buf_vpu_addr + offsetof(struct ivpu_ipc_tx_buf, jsm);
+
+	if (tx_buf->ipc.status != IVPU_IPC_HDR_FREE)
+		ivpu_warn(vdev, "IPC message vpu:0x%x not released by firmware\n",
+			  tx_buf_vpu_addr);
+
+	if (tx_buf->jsm.status != VPU_JSM_MSG_FREE)
+		ivpu_warn(vdev, "JSM message vpu:0x%x not released by firmware\n",
+			  jsm_vpu_addr);
+
+	memset(tx_buf, 0, sizeof(*tx_buf));
+	tx_buf->ipc.data_addr = jsm_vpu_addr;
+	/* TODO: Set data_size to actual JSM message size, not union of all messages */
+	tx_buf->ipc.data_size = sizeof(*req);
+	tx_buf->ipc.channel = cons->channel;
+	tx_buf->ipc.src_node = 0;
+	tx_buf->ipc.dst_node = 1;
+	tx_buf->ipc.status = IVPU_IPC_HDR_ALLOCATED;
+	tx_buf->jsm.type = req->type;
+	tx_buf->jsm.status = VPU_JSM_MSG_ALLOCATED;
+	tx_buf->jsm.payload = req->payload;
+
+	req->request_id = atomic_inc_return(&ipc->request_id);
+	tx_buf->jsm.request_id = req->request_id;
+	cons->request_id = req->request_id;
+	wmb(); /* Flush WC buffers for IPC, JSM msgs */
+
+	cons->tx_vpu_addr = tx_buf_vpu_addr;
+
+	ivpu_jsm_msg_dump(vdev, "TX", &tx_buf->jsm, jsm_vpu_addr);
+	ivpu_ipc_msg_dump(vdev, "TX", &tx_buf->ipc, tx_buf_vpu_addr);
+
+	return 0;
+}
+
+static void ivpu_ipc_tx_release(struct ivpu_device *vdev, u32 vpu_addr)
+{
+	struct ivpu_ipc_info *ipc = vdev->ipc;
+
+	if (vpu_addr)
+		gen_pool_free(ipc->mm_tx, vpu_addr, sizeof(struct ivpu_ipc_tx_buf));
+}
+
+static void ivpu_ipc_tx(struct ivpu_device *vdev, u32 vpu_addr)
+{
+	ivpu_hw_reg_ipc_tx_set(vdev, vpu_addr);
+}
+
+void
+ivpu_ipc_consumer_add(struct ivpu_device *vdev, struct ivpu_ipc_consumer *cons, u32 channel)
+{
+	struct ivpu_ipc_info *ipc = vdev->ipc;
+
+	INIT_LIST_HEAD(&cons->link);
+	cons->channel = channel;
+	cons->tx_vpu_addr = 0;
+	cons->request_id = 0;
+	spin_lock_init(&cons->rx_msg_lock);
+	INIT_LIST_HEAD(&cons->rx_msg_list);
+	init_waitqueue_head(&cons->rx_msg_wq);
+
+	spin_lock_irq(&ipc->cons_list_lock);
+	list_add_tail(&cons->link, &ipc->cons_list);
+	spin_unlock_irq(&ipc->cons_list_lock);
+}
+
+void ivpu_ipc_consumer_del(struct ivpu_device *vdev, struct ivpu_ipc_consumer *cons)
+{
+	struct ivpu_ipc_info *ipc = vdev->ipc;
+	struct ivpu_ipc_rx_msg *rx_msg, *r;
+
+	spin_lock_irq(&ipc->cons_list_lock);
+	list_del(&cons->link);
+	spin_unlock_irq(&ipc->cons_list_lock);
+
+	spin_lock_irq(&cons->rx_msg_lock);
+	list_for_each_entry_safe(rx_msg, r, &cons->rx_msg_list, link) {
+		list_del(&rx_msg->link);
+		ivpu_ipc_rx_mark_free(vdev, rx_msg->ipc_hdr, rx_msg->jsm_msg);
+		atomic_dec(&ipc->rx_msg_count);
+		kfree(rx_msg);
+	}
+	spin_unlock_irq(&cons->rx_msg_lock);
+
+	ivpu_ipc_tx_release(vdev, cons->tx_vpu_addr);
+}
+
+static int
+ivpu_ipc_send(struct ivpu_device *vdev, struct ivpu_ipc_consumer *cons, struct vpu_jsm_msg *req)
+{
+	struct ivpu_ipc_info *ipc = vdev->ipc;
+	int ret;
+
+	ret = mutex_lock_interruptible(&ipc->lock);
+	if (ret)
+		return ret;
+
+	if (!ipc->on) {
+		ret = -EAGAIN;
+		goto unlock;
+	}
+
+	ret = ivpu_ipc_tx_prepare(vdev, cons, req);
+	if (ret)
+		goto unlock;
+
+	ivpu_ipc_tx(vdev, cons->tx_vpu_addr);
+
+unlock:
+	mutex_unlock(&ipc->lock);
+	return ret;
+}
+
+int ivpu_ipc_receive(struct ivpu_device *vdev, struct ivpu_ipc_consumer *cons,
+		     struct ivpu_ipc_hdr *ipc_buf,
+		     struct vpu_jsm_msg *ipc_payload, unsigned long timeout_ms)
+{
+	struct ivpu_ipc_info *ipc = vdev->ipc;
+	struct ivpu_ipc_rx_msg *rx_msg;
+	int wait_ret, ret = 0;
+
+	wait_ret = wait_event_interruptible_timeout(cons->rx_msg_wq,
+						    (IS_KTHREAD() && kthread_should_stop()) ||
+						    !list_empty(&cons->rx_msg_list),
+						    msecs_to_jiffies(timeout_ms));
+
+	if (IS_KTHREAD() && kthread_should_stop())
+		return -EINTR;
+
+	if (wait_ret == 0)
+		return -ETIMEDOUT;
+
+	if (wait_ret < 0)
+		return -ERESTARTSYS;
+
+	spin_lock_irq(&cons->rx_msg_lock);
+	rx_msg = list_first_entry_or_null(&cons->rx_msg_list, struct ivpu_ipc_rx_msg, link);
+	if (!rx_msg) {
+		spin_unlock_irq(&cons->rx_msg_lock);
+		return -EAGAIN;
+	}
+	list_del(&rx_msg->link);
+	spin_unlock_irq(&cons->rx_msg_lock);
+
+	if (ipc_buf)
+		memcpy(ipc_buf, rx_msg->ipc_hdr, sizeof(*ipc_buf));
+	if (rx_msg->jsm_msg) {
+		u32 size = min_t(int, rx_msg->ipc_hdr->data_size, sizeof(*ipc_payload));
+
+		if (rx_msg->jsm_msg->result != VPU_JSM_STATUS_SUCCESS) {
+			ivpu_dbg(vdev, IPC, "IPC resp result error: %d\n", rx_msg->jsm_msg->result);
+			ret = -EBADMSG;
+		}
+
+		if (ipc_payload)
+			memcpy(ipc_payload, rx_msg->jsm_msg, size);
+	}
+
+	ivpu_ipc_rx_mark_free(vdev, rx_msg->ipc_hdr, rx_msg->jsm_msg);
+	atomic_dec(&ipc->rx_msg_count);
+	kfree(rx_msg);
+
+	return ret;
+}
+
+static int
+ivpu_ipc_send_receive_internal(struct ivpu_device *vdev, struct vpu_jsm_msg *req,
+			       enum vpu_ipc_msg_type expected_resp_type,
+			       struct vpu_jsm_msg *resp, u32 channel,
+			       unsigned long timeout_ms)
+{
+	struct ivpu_ipc_consumer cons;
+	int ret;
+
+	ivpu_ipc_consumer_add(vdev, &cons, channel);
+
+	ret = ivpu_ipc_send(vdev, &cons, req);
+	if (ret) {
+		ivpu_warn(vdev, "IPC send failed: %d\n", ret);
+		goto consumer_del;
+	}
+
+	ret = ivpu_ipc_receive(vdev, &cons, NULL, resp, timeout_ms);
+	if (ret) {
+		ivpu_warn(vdev, "IPC receive failed: type 0x%x, ret %d\n", req->type, ret);
+		goto consumer_del;
+	}
+
+	if (resp->type != expected_resp_type) {
+		ivpu_warn(vdev, "Invalid JSM response type: 0x%x\n", resp->type);
+		ret = -EBADE;
+	}
+
+consumer_del:
+	ivpu_ipc_consumer_del(vdev, &cons);
+	return ret;
+}
+
+int ivpu_ipc_send_receive(struct ivpu_device *vdev, struct vpu_jsm_msg *req,
+			  enum vpu_ipc_msg_type expected_resp_type,
+			  struct vpu_jsm_msg *resp, u32 channel,
+			  unsigned long timeout_ms)
+{
+	struct vpu_jsm_msg hb_req = { .type = VPU_JSM_MSG_QUERY_ENGINE_HB };
+	struct vpu_jsm_msg hb_resp;
+	int ret;
+
+	ret = ivpu_ipc_send_receive_internal(vdev, req, expected_resp_type, resp,
+					     channel, timeout_ms);
+	if (ret != -ETIMEDOUT)
+		return ret;
+
+	ret = ivpu_ipc_send_receive_internal(vdev, &hb_req, VPU_JSM_MSG_QUERY_ENGINE_HB_DONE,
+					     &hb_resp, VPU_IPC_CHAN_ASYNC_CMD, vdev->timeout.jsm);
+	if (ret == -ETIMEDOUT)
+		ivpu_hw_diagnose_failure(vdev);
+
+	return ret;
+}
+
+static bool
+ivpu_ipc_match_consumer(struct ivpu_device *vdev, struct ivpu_ipc_consumer *cons,
+			struct ivpu_ipc_hdr *ipc_hdr, struct vpu_jsm_msg *jsm_msg)
+{
+	if (cons->channel != ipc_hdr->channel)
+		return false;
+
+	if (!jsm_msg || jsm_msg->request_id == cons->request_id)
+		return true;
+
+	return false;
+}
+
+static void
+ivpu_ipc_dispatch(struct ivpu_device *vdev, struct ivpu_ipc_consumer *cons,
+		  struct ivpu_ipc_hdr *ipc_hdr, struct vpu_jsm_msg *jsm_msg)
+{
+	struct ivpu_ipc_info *ipc = vdev->ipc;
+	struct ivpu_ipc_rx_msg *rx_msg;
+	unsigned long flags;
+
+	lockdep_assert_held(&ipc->cons_list_lock);
+
+	rx_msg = kzalloc(sizeof(*rx_msg), GFP_ATOMIC);
+	if (!rx_msg) {
+		ivpu_ipc_rx_mark_free(vdev, ipc_hdr, jsm_msg);
+		return;
+	}
+
+	atomic_inc(&ipc->rx_msg_count);
+
+	rx_msg->ipc_hdr = ipc_hdr;
+	rx_msg->jsm_msg = jsm_msg;
+
+	spin_lock_irqsave(&cons->rx_msg_lock, flags);
+	list_add_tail(&rx_msg->link, &cons->rx_msg_list);
+	spin_unlock_irqrestore(&cons->rx_msg_lock, flags);
+
+	wake_up(&cons->rx_msg_wq);
+}
+
+int ivpu_ipc_irq_handler(struct ivpu_device *vdev)
+{
+	struct ivpu_ipc_info *ipc = vdev->ipc;
+	struct ivpu_ipc_consumer *cons;
+	struct ivpu_ipc_hdr *ipc_hdr;
+	struct vpu_jsm_msg *jsm_msg;
+	unsigned long flags;
+	bool dispatched;
+	u32 vpu_addr;
+
+	/*
+	 * Driver needs to purge all messages from IPC FIFO to clear IPC interrupt.
+	 * Without purge IPC FIFO to 0 next IPC interrupts won't be generated.
+	 */
+	while (ivpu_hw_reg_ipc_rx_count_get(vdev)) {
+		vpu_addr = ivpu_hw_reg_ipc_rx_addr_get(vdev);
+		if (vpu_addr == REG_IO_ERROR) {
+			ivpu_err(vdev, "Failed to read IPC rx addr register\n");
+			return -EIO;
+		}
+
+		ipc_hdr = ivpu_to_cpu_addr(ipc->mem_rx, vpu_addr);
+		if (!ipc_hdr) {
+			ivpu_warn(vdev, "IPC msg 0x%x out of range\n", vpu_addr);
+			continue;
+		}
+		ivpu_ipc_msg_dump(vdev, "RX", ipc_hdr, vpu_addr);
+
+		jsm_msg = NULL;
+		if (ipc_hdr->channel != IVPU_IPC_CHAN_BOOT_MSG) {
+			jsm_msg = ivpu_to_cpu_addr(ipc->mem_rx, ipc_hdr->data_addr);
+			if (!jsm_msg) {
+				ivpu_warn(vdev, "JSM msg 0x%x out of range\n", ipc_hdr->data_addr);
+				ivpu_ipc_rx_mark_free(vdev, ipc_hdr, NULL);
+				continue;
+			}
+			ivpu_jsm_msg_dump(vdev, "RX", jsm_msg, ipc_hdr->data_addr);
+		}
+
+		if (atomic_read(&ipc->rx_msg_count) > IPC_MAX_RX_MSG) {
+			ivpu_warn(vdev, "IPC RX msg dropped, msg count %d\n", IPC_MAX_RX_MSG);
+			ivpu_ipc_rx_mark_free(vdev, ipc_hdr, jsm_msg);
+			continue;
+		}
+
+		dispatched = false;
+		spin_lock_irqsave(&ipc->cons_list_lock, flags);
+		list_for_each_entry(cons, &ipc->cons_list, link) {
+			if (ivpu_ipc_match_consumer(vdev, cons, ipc_hdr, jsm_msg)) {
+				ivpu_ipc_dispatch(vdev, cons, ipc_hdr, jsm_msg);
+				dispatched = true;
+				break;
+			}
+		}
+		spin_unlock_irqrestore(&ipc->cons_list_lock, flags);
+
+		if (!dispatched) {
+			ivpu_dbg(vdev, IPC, "IPC RX msg 0x%x dropped (no consumer)\n", vpu_addr);
+			ivpu_ipc_rx_mark_free(vdev, ipc_hdr, jsm_msg);
+		}
+	}
+
+	return 0;
+}
+
+int ivpu_ipc_init(struct ivpu_device *vdev)
+{
+	struct ivpu_ipc_info *ipc = vdev->ipc;
+	int ret = -ENOMEM;
+
+	ipc->mem_tx = ivpu_bo_alloc_internal(vdev, 0, SZ_16K, DRM_IVPU_BO_WC);
+	if (!ipc->mem_tx)
+		return ret;
+
+	ipc->mem_rx = ivpu_bo_alloc_internal(vdev, 0, SZ_16K, DRM_IVPU_BO_WC);
+	if (!ipc->mem_rx)
+		goto err_free_tx;
+
+	ipc->mm_tx = devm_gen_pool_create(vdev->drm.dev, __ffs(IVPU_IPC_ALIGNMENT),
+					  -1, "TX_IPC_JSM");
+	if (IS_ERR(ipc->mm_tx)) {
+		ret = PTR_ERR(ipc->mm_tx);
+		ivpu_err(vdev, "Failed to create gen pool, %pe\n", ipc->mm_tx);
+		goto err_free_rx;
+	}
+
+	ret = gen_pool_add(ipc->mm_tx, ipc->mem_tx->vpu_addr, ipc->mem_tx->base.size, -1);
+	if (ret) {
+		ivpu_err(vdev, "gen_pool_add failed, ret %d\n", ret);
+		goto err_free_rx;
+	}
+
+	INIT_LIST_HEAD(&ipc->cons_list);
+	spin_lock_init(&ipc->cons_list_lock);
+	drmm_mutex_init(&vdev->drm, &ipc->lock);
+
+	ivpu_ipc_reset(vdev);
+	return 0;
+
+err_free_rx:
+	ivpu_bo_free_internal(ipc->mem_rx);
+err_free_tx:
+	ivpu_bo_free_internal(ipc->mem_tx);
+	return ret;
+}
+
+void ivpu_ipc_fini(struct ivpu_device *vdev)
+{
+	ivpu_ipc_mem_fini(vdev);
+}
+
+void ivpu_ipc_enable(struct ivpu_device *vdev)
+{
+	struct ivpu_ipc_info *ipc = vdev->ipc;
+
+	mutex_lock(&ipc->lock);
+	ipc->on = true;
+	mutex_unlock(&ipc->lock);
+}
+
+void ivpu_ipc_disable(struct ivpu_device *vdev)
+{
+	struct ivpu_ipc_info *ipc = vdev->ipc;
+	struct ivpu_ipc_consumer *cons, *c;
+	unsigned long flags;
+
+	mutex_lock(&ipc->lock);
+	ipc->on = false;
+	mutex_unlock(&ipc->lock);
+
+	spin_lock_irqsave(&ipc->cons_list_lock, flags);
+	list_for_each_entry_safe(cons, c, &ipc->cons_list, link)
+		wake_up(&cons->rx_msg_wq);
+	spin_unlock_irqrestore(&ipc->cons_list_lock, flags);
+}
+
+void ivpu_ipc_reset(struct ivpu_device *vdev)
+{
+	struct ivpu_ipc_info *ipc = vdev->ipc;
+
+	mutex_lock(&ipc->lock);
+
+	memset(ipc->mem_tx->kvaddr, 0, ipc->mem_tx->base.size);
+	memset(ipc->mem_rx->kvaddr, 0, ipc->mem_rx->base.size);
+	wmb(); /* Flush WC buffers for TX and RX rings */
+
+	mutex_unlock(&ipc->lock);
+}

drivers/accel/ivpu/ivpu_ipc.h

+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (C) 2020-2023 Intel Corporation
+ */
+
+#ifndef __IVPU_IPC_H__
+#define __IVPU_IPC_H__
+
+#include <linux/interrupt.h>
+#include <linux/spinlock.h>
+
+#include "vpu_jsm_api.h"
+
+struct ivpu_bo;
+
+/* VPU FW boot notification */
+#define IVPU_IPC_CHAN_BOOT_MSG		0x3ff
+#define IVPU_IPC_BOOT_MSG_DATA_ADDR	0x424f4f54
+
+/* The alignment to be used for IPC Buffers and IPC Data. */
+#define IVPU_IPC_ALIGNMENT	   64
+
+#define IVPU_IPC_HDR_FREE	   0
+#define IVPU_IPC_HDR_ALLOCATED	   0
+
+/**
+ * struct ivpu_ipc_hdr - The IPC message header structure, exchanged
+ * with the VPU device firmware.
+ * @data_addr: The VPU address of the payload (JSM message)
+ * @data_size: The size of the payload.
+ * @channel: The channel used.
+ * @src_node: The Node ID of the sender.
+ * @dst_node: The Node ID of the intended receiver.
+ * @status: IPC buffer usage status
+ */
+struct ivpu_ipc_hdr {
+	u32 data_addr;
+	u32 data_size;
+	u16 channel;
+	u8 src_node;
+	u8 dst_node;
+	u8 status;
+} __packed __aligned(IVPU_IPC_ALIGNMENT);
+
+struct ivpu_ipc_consumer {
+	struct list_head link;
+	u32 channel;
+	u32 tx_vpu_addr;
+	u32 request_id;
+
+	spinlock_t rx_msg_lock; /* Protects rx_msg_list */
+	struct list_head rx_msg_list;
+	wait_queue_head_t rx_msg_wq;
+};
+
+struct ivpu_ipc_info {
+	struct gen_pool *mm_tx;
+	struct ivpu_bo *mem_tx;
+	struct ivpu_bo *mem_rx;
+
+	atomic_t rx_msg_count;
+
+	spinlock_t cons_list_lock; /* Protects cons_list */
+	struct list_head cons_list;
+
+	atomic_t request_id;
+	struct mutex lock; /* Lock on status */
+	bool on;
+};
+
+int ivpu_ipc_init(struct ivpu_device *vdev);
+void ivpu_ipc_fini(struct ivpu_device *vdev);
+
+void ivpu_ipc_enable(struct ivpu_device *vdev);
+void ivpu_ipc_disable(struct ivpu_device *vdev);
+void ivpu_ipc_reset(struct ivpu_device *vdev);
+
+int ivpu_ipc_irq_handler(struct ivpu_device *vdev);
+
+void ivpu_ipc_consumer_add(struct ivpu_device *vdev, struct ivpu_ipc_consumer *cons,
+			   u32 channel);
+void ivpu_ipc_consumer_del(struct ivpu_device *vdev, struct ivpu_ipc_consumer *cons);
+
+int ivpu_ipc_receive(struct ivpu_device *vdev, struct ivpu_ipc_consumer *cons,
+		     struct ivpu_ipc_hdr *ipc_buf, struct vpu_jsm_msg *ipc_payload,
+		     unsigned long timeout_ms);
+
+int ivpu_ipc_send_receive(struct ivpu_device *vdev, struct vpu_jsm_msg *req,
+			  enum vpu_ipc_msg_type expected_resp_type,
+			  struct vpu_jsm_msg *resp, u32 channel,
+			  unsigned long timeout_ms);
+
+#endif /* __IVPU_IPC_H__ */

drivers/accel/ivpu/ivpu_jsm_msg.c

+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2020-2023 Intel Corporation
+ */
+
+#include "ivpu_drv.h"
+#include "ivpu_ipc.h"
+#include "ivpu_jsm_msg.h"
+
+int ivpu_jsm_register_db(struct ivpu_device *vdev, u32 ctx_id, u32 db_id,
+			 u64 jobq_base, u32 jobq_size)
+{
+	struct vpu_jsm_msg req = { .type = VPU_JSM_MSG_REGISTER_DB };
+	struct vpu_jsm_msg resp;
+	int ret = 0;
+
+	req.payload.register_db.db_idx = db_id;
+	req.payload.register_db.jobq_base = jobq_base;
+	req.payload.register_db.jobq_size = jobq_size;
+	req.payload.register_db.host_ssid = ctx_id;
+
+	ret = ivpu_ipc_send_receive(vdev, &req, VPU_JSM_MSG_REGISTER_DB_DONE, &resp,
+				    VPU_IPC_CHAN_ASYNC_CMD, vdev->timeout.jsm);
+	if (ret) {
+		ivpu_err(vdev, "Failed to register doorbell %d: %d\n", db_id, ret);
+		return ret;
+	}
+
+	ivpu_dbg(vdev, JSM, "Doorbell %d registered to context %d\n", db_id, ctx_id);
+
+	return 0;
+}
+
+int ivpu_jsm_unregister_db(struct ivpu_device *vdev, u32 db_id)
+{
+	struct vpu_jsm_msg req = { .type = VPU_JSM_MSG_UNREGISTER_DB };
+	struct vpu_jsm_msg resp;
+	int ret = 0;
+
+	req.payload.unregister_db.db_idx = db_id;
+
+	ret = ivpu_ipc_send_receive(vdev, &req, VPU_JSM_MSG_UNREGISTER_DB_DONE, &resp,
+				    VPU_IPC_CHAN_ASYNC_CMD, vdev->timeout.jsm);
+	if (ret) {
+		ivpu_warn(vdev, "Failed to unregister doorbell %d: %d\n", db_id, ret);
+		return ret;
+	}
+
+	ivpu_dbg(vdev, JSM, "Doorbell %d unregistered\n", db_id);
+
+	return 0;
+}
+
+int ivpu_jsm_get_heartbeat(struct ivpu_device *vdev, u32 engine, u64 *heartbeat)
+{
+	struct vpu_jsm_msg req = { .type = VPU_JSM_MSG_QUERY_ENGINE_HB };
+	struct vpu_jsm_msg resp;
+	int ret;
+
+	if (engine > VPU_ENGINE_COPY)
+		return -EINVAL;
+
+	req.payload.query_engine_hb.engine_idx = engine;
+
+	ret = ivpu_ipc_send_receive(vdev, &req, VPU_JSM_MSG_QUERY_ENGINE_HB_DONE, &resp,
+				    VPU_IPC_CHAN_ASYNC_CMD, vdev->timeout.jsm);
+	if (ret) {
+		ivpu_err(vdev, "Failed to get heartbeat from engine %d: %d\n", engine, ret);
+		return ret;
+	}
+
+	*heartbeat = resp.payload.query_engine_hb_done.heartbeat;
+	return ret;
+}
+
+int ivpu_jsm_reset_engine(struct ivpu_device *vdev, u32 engine)
+{
+	struct vpu_jsm_msg req = { .type = VPU_JSM_MSG_ENGINE_RESET };
+	struct vpu_jsm_msg resp;
+	int ret;
+
+	if (engine > VPU_ENGINE_COPY)
+		return -EINVAL;
+
+	req.payload.engine_reset.engine_idx = engine;
+
+	ret = ivpu_ipc_send_receive(vdev, &req, VPU_JSM_MSG_ENGINE_RESET_DONE, &resp,
+				    VPU_IPC_CHAN_ASYNC_CMD, vdev->timeout.jsm);
+	if (ret)
+		ivpu_err(vdev, "Failed to reset engine %d: %d\n", engine, ret);
+
+	return ret;
+}
+
+int ivpu_jsm_preempt_engine(struct ivpu_device *vdev, u32 engine, u32 preempt_id)
+{
+	struct vpu_jsm_msg req = { .type = VPU_JSM_MSG_ENGINE_PREEMPT };
+	struct vpu_jsm_msg resp;
+	int ret;
+
+	if (engine > VPU_ENGINE_COPY)
+		return -EINVAL;
+
+	req.payload.engine_preempt.engine_idx = engine;
+	req.payload.engine_preempt.preempt_id = preempt_id;
+
+	ret = ivpu_ipc_send_receive(vdev, &req, VPU_JSM_MSG_ENGINE_PREEMPT_DONE, &resp,
+				    VPU_IPC_CHAN_ASYNC_CMD, vdev->timeout.jsm);
+	if (ret)
+		ivpu_err(vdev, "Failed to preempt engine %d: %d\n", engine, ret);
+
+	return ret;
+}
+
+int ivpu_jsm_dyndbg_control(struct ivpu_device *vdev, char *command, size_t size)
+{
+	struct vpu_jsm_msg req = { .type = VPU_JSM_MSG_DYNDBG_CONTROL };
+	struct vpu_jsm_msg resp;
+	int ret;
+
+	if (!strncpy(req.payload.dyndbg_control.dyndbg_cmd, command, VPU_DYNDBG_CMD_MAX_LEN - 1))
+		return -ENOMEM;
+
+	ret = ivpu_ipc_send_receive(vdev, &req, VPU_JSM_MSG_DYNDBG_CONTROL_RSP, &resp,
+				    VPU_IPC_CHAN_ASYNC_CMD, vdev->timeout.jsm);
+	if (ret)
+		ivpu_warn(vdev, "Failed to send command \"%s\": ret %d\n", command, ret);
+
+	return ret;
+}
+
+int ivpu_jsm_trace_get_capability(struct ivpu_device *vdev, u32 *trace_destination_mask,
+				  u64 *trace_hw_component_mask)
+{
+	struct vpu_jsm_msg req = { .type = VPU_JSM_MSG_TRACE_GET_CAPABILITY };
+	struct vpu_jsm_msg resp;
+	int ret;
+
+	ret = ivpu_ipc_send_receive(vdev, &req, VPU_JSM_MSG_TRACE_GET_CAPABILITY_RSP, &resp,
+				    VPU_IPC_CHAN_ASYNC_CMD, vdev->timeout.jsm);
+	if (ret) {
+		ivpu_warn(vdev, "Failed to get trace capability: %d\n", ret);
+		return ret;
+	}
+
+	*trace_destination_mask = resp.payload.trace_capability.trace_destination_mask;
+	*trace_hw_component_mask = resp.payload.trace_capability.trace_hw_component_mask;
+
+	return ret;
+}
+
+int ivpu_jsm_trace_set_config(struct ivpu_device *vdev, u32 trace_level, u32 trace_destination_mask,
+			      u64 trace_hw_component_mask)
+{
+	struct vpu_jsm_msg req = { .type = VPU_JSM_MSG_TRACE_SET_CONFIG };
+	struct vpu_jsm_msg resp;
+	int ret;
+
+	req.payload.trace_config.trace_level = trace_level;
+	req.payload.trace_config.trace_destination_mask = trace_destination_mask;
+	req.payload.trace_config.trace_hw_component_mask = trace_hw_component_mask;
+
+	ret = ivpu_ipc_send_receive(vdev, &req, VPU_JSM_MSG_TRACE_SET_CONFIG_RSP, &resp,
+				    VPU_IPC_CHAN_ASYNC_CMD, vdev->timeout.jsm);
+	if (ret)
+		ivpu_warn(vdev, "Failed to set config: %d\n", ret);
+
+	return ret;
+}

drivers/accel/ivpu/ivpu_jsm_msg.h

+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (C) 2020-2023 Intel Corporation
+ */
+
+#ifndef __IVPU_JSM_MSG_H__
+#define __IVPU_JSM_MSG_H__
+
+#include "vpu_jsm_api.h"
+
+int ivpu_jsm_register_db(struct ivpu_device *vdev, u32 ctx_id, u32 db_id,
+			 u64 jobq_base, u32 jobq_size);
+int ivpu_jsm_unregister_db(struct ivpu_device *vdev, u32 db_id);
+int ivpu_jsm_get_heartbeat(struct ivpu_device *vdev, u32 engine, u64 *heartbeat);
+int ivpu_jsm_reset_engine(struct ivpu_device *vdev, u32 engine);
+int ivpu_jsm_preempt_engine(struct ivpu_device *vdev, u32 engine, u32 preempt_id);
+int ivpu_jsm_dyndbg_control(struct ivpu_device *vdev, char *command, size_t size);
+int ivpu_jsm_trace_get_capability(struct ivpu_device *vdev, u32 *trace_destination_mask,
+				  u64 *trace_hw_component_mask);
+int ivpu_jsm_trace_set_config(struct ivpu_device *vdev, u32 trace_level, u32 trace_destination_mask,
+			      u64 trace_hw_component_mask);
+
+#endif