media: venus: vdec: decoded picture buffer handling during reconfig sequence

In existing implementation, driver is freeing and un-mapping all the
decoded picture buffers(DPB) as part of dynamic resolution change(DRC)
handling. As a result, when firmware try to access the DPB buffer, from
previous sequence, SMMU context fault is seen due to the buffer being
already unmapped.

With this change, driver defines ownership of each DPB buffer. If a buffer
is owned by firmware, driver would skip from un-mapping the same.

Signed-off-by: Mansur Alisha Shaik <mansur@codeaurora.org>
Signed-off-by: Stanimir Varbanov <stanimir.varbanov@linaro.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

1 files changed, 50 insertions, 1 deletions

diff --git a/drivers/media/platform/qcom/venus/helpers.c b/drivers/media/platform/qcom/venus/helpers.c
index caf47ca6a950..84c3a511ec31 100644
--- a/drivers/media/platform/qcom/venus/helpers.c
+++ b/drivers/media/platform/qcom/venus/helpers.c
@@ -3,6 +3,7 @@
  * Copyright (c) 2012-2016, The Linux Foundation. All rights reserved.
  * Copyright (C) 2017 Linaro Ltd.
  */
+#include <linux/idr.h>
 #include <linux/list.h>
 #include <linux/mutex.h>
 #include <linux/slab.h>
@@ -21,6 +22,11 @@
 #define NUM_MBS_720P	(((ALIGN(1280, 16)) >> 4) * ((ALIGN(736, 16)) >> 4))
 #define NUM_MBS_4K	(((ALIGN(4096, 16)) >> 4) * ((ALIGN(2304, 16)) >> 4))
 
+enum dpb_buf_owner {
+	DRIVER,
+	FIRMWARE,
+};
+
 struct intbuf {
 	struct list_head list;
 	u32 type;
@@ -28,6 +34,8 @@ struct intbuf {
 	void *va;
 	dma_addr_t da;
 	unsigned long attrs;
+	enum dpb_buf_owner owned_by;
+	u32 dpb_out_tag;
 };
 
 bool venus_helper_check_codec(struct venus_inst *inst, u32 v4l2_pixfmt)
@@ -95,9 +103,16 @@ int venus_helper_queue_dpb_bufs(struct venus_inst *inst)
 		fdata.device_addr = buf->da;
 		fdata.buffer_type = buf->type;
 
+		if (buf->owned_by == FIRMWARE)
+			continue;
+
+		fdata.clnt_data = buf->dpb_out_tag;
+
 		ret = hfi_session_process_buf(inst, &fdata);
 		if (ret)
 			goto fail;
+
+		buf->owned_by = FIRMWARE;
 	}
 
 fail:
@@ -110,13 +125,19 @@ int venus_helper_free_dpb_bufs(struct venus_inst *inst)
 	struct intbuf *buf, *n;
 
 	list_for_each_entry_safe(buf, n, &inst->dpbbufs, list) {
+		if (buf->owned_by == FIRMWARE)
+			continue;
+
+		ida_free(&inst->dpb_ids, buf->dpb_out_tag);
+
 		list_del_init(&buf->list);
 		dma_free_attrs(inst->core->dev, buf->size, buf->va, buf->da,
 			       buf->attrs);
 		kfree(buf);
 	}
 
-	INIT_LIST_HEAD(&inst->dpbbufs);
+	if (list_empty(&inst->dpbbufs))
+		INIT_LIST_HEAD(&inst->dpbbufs);
 
 	return 0;
 }
@@ -134,6 +155,7 @@ int venus_helper_alloc_dpb_bufs(struct venus_inst *inst)
 	unsigned int i;
 	u32 count;
 	int ret;
+	int id;
 
 	/* no need to allocate dpb buffers */
 	if (!inst->dpb_fmt)
@@ -171,6 +193,15 @@ int venus_helper_alloc_dpb_bufs(struct venus_inst *inst)
 			ret = -ENOMEM;
 			goto fail;
 		}
+		buf->owned_by = DRIVER;
+
+		id = ida_alloc_min(&inst->dpb_ids, VB2_MAX_FRAME, GFP_KERNEL);
+		if (id < 0) {
+			ret = id;
+			goto fail;
+		}
+
+		buf->dpb_out_tag = id;
 
 		list_add_tail(&buf->list, &inst->dpbbufs);
 	}
@@ -1371,6 +1402,24 @@ venus_helper_find_buf(struct venus_inst *inst, unsigned int type, u32 idx)
 }
 EXPORT_SYMBOL_GPL(venus_helper_find_buf);
 
+void venus_helper_change_dpb_owner(struct venus_inst *inst,
+				   struct vb2_v4l2_buffer *vbuf, unsigned int type,
+				   unsigned int buf_type, u32 tag)
+{
+	struct intbuf *dpb_buf;
+
+	if (!V4L2_TYPE_IS_CAPTURE(type) ||
+	    buf_type != inst->dpb_buftype)
+		return;
+
+	list_for_each_entry(dpb_buf, &inst->dpbbufs, list)
+		if (dpb_buf->dpb_out_tag == tag) {
+			dpb_buf->owned_by = DRIVER;
+			break;
+		}
+}
+EXPORT_SYMBOL_GPL(venus_helper_change_dpb_owner);
+
 int venus_helper_vb2_buf_init(struct vb2_buffer *vb)
 {
 	struct venus_inst *inst = vb2_get_drv_priv(vb->vb2_queue);