[PATCH 08/15] soc: mediatek: Add cmdq_pkt_finalize_loop to CMDQ driver

[Jason-JH.Lin]

Add cmdq_pkt_finalize_loop to CMDQ driver.

cmdq_pkt_finalize_loop appends end of command(EOC) instruction and
jump to start of command buffer instruction to make the command
buffer loopable.

Signed-off-by: Jason-JH.Lin <jason-jh.lin at mediatek.com>
---
 drivers/soc/mediatek/mtk-cmdq-helper.c | 23 +++++++++++++++++++++++
 include/linux/soc/mediatek/mtk-cmdq.h  |  8 ++++++++
 2 files changed, 31 insertions(+)

diff --git a/drivers/soc/mediatek/mtk-cmdq-helper.c b/drivers/soc/mediatek/mtk-cmdq-helper.c
index 4be2a18a4a02..bbb127620bb3 100644
--- a/drivers/soc/mediatek/mtk-cmdq-helper.c
+++ b/drivers/soc/mediatek/mtk-cmdq-helper.c
@@ -475,6 +475,29 @@ int cmdq_pkt_finalize(struct cmdq_pkt *pkt)
 }
 EXPORT_SYMBOL(cmdq_pkt_finalize);
 
+int cmdq_pkt_finalize_loop(struct cmdq_pkt *pkt)
+{
+	struct cmdq_instruction inst = { {0} };
+	int err;
+
+	/* insert EOC and generate IRQ for each command iteration */
+	inst.op = CMDQ_CODE_EOC;
+	inst.value = CMDQ_EOC_IRQ_EN;
+	err = cmdq_pkt_append_command(pkt, inst);
+	if (err < 0)
+		return err;
+
+	/* JUMP to start of pkt */
+	err = cmdq_pkt_jump(pkt, pkt->pa_base);
+	if (err < 0)
+		return err;
+
+	pkt->loop = true;
+
+	return err;
+}
+EXPORT_SYMBOL(cmdq_pkt_finalize_loop);
+
 int cmdq_pkt_flush_async(struct cmdq_pkt *pkt)
 {
 	int err;
diff --git a/include/linux/soc/mediatek/mtk-cmdq.h b/include/linux/soc/mediatek/mtk-cmdq.h
index 837ad8656adc..38a8e47da338 100644
--- a/include/linux/soc/mediatek/mtk-cmdq.h
+++ b/include/linux/soc/mediatek/mtk-cmdq.h
@@ -323,6 +323,14 @@ int cmdq_pkt_jump(struct cmdq_pkt *pkt, dma_addr_t addr);
  */
 int cmdq_pkt_finalize(struct cmdq_pkt *pkt);
 
+/**
+ * cmdq_pkt_finalize_loop() - Append EOC and jump to start command.
+ * @pkt:	the CMDQ packet
+ *
+ * Return: 0 for success; else the error code is returned
+ */
+int cmdq_pkt_finalize_loop(struct cmdq_pkt *pkt);
+
 /**
  * cmdq_pkt_flush_async() - trigger CMDQ to asynchronously execute the CMDQ
  *                          packet and call back at the end of done packet
-- 
2.18.0