[PATCH v1 10/12] soc: mediatek: cmdq: add loop function

[Dennis YC Hsieh]

Add finalize loop function in cmdq helper functions which loop whole pkt
in gce hardware thread without cpu operation.

Signed-off-by: Dennis YC Hsieh <dennis-yc.hsieh@xxxxxxxxxxxx>
---
 drivers/soc/mediatek/mtk-cmdq-helper.c |   41 ++++++++++++++++++++++++++++++++
 include/linux/soc/mediatek/mtk-cmdq.h  |    8 +++++++
 2 files changed, 49 insertions(+)

diff --git a/drivers/soc/mediatek/mtk-cmdq-helper.c b/drivers/soc/mediatek/mtk-cmdq-helper.c
index 4235cf8..3b10241 100644
--- a/drivers/soc/mediatek/mtk-cmdq-helper.c
+++ b/drivers/soc/mediatek/mtk-cmdq-helper.c
@@ -385,12 +385,27 @@ int cmdq_pkt_assign(struct cmdq_pkt *pkt, u16 reg_idx, u32 value)
 }
 EXPORT_SYMBOL(cmdq_pkt_assign);
 
+static bool cmdq_pkt_finalized(struct cmdq_pkt *pkt)
+{
+	struct cmdq_instruction *inst;
+
+	if (pkt->cmd_buf_size < 2 * CMDQ_INST_SIZE)
+		return false;
+
+	inst = pkt->va_base + pkt->cmd_buf_size - 2 * CMDQ_INST_SIZE;
+	return inst->op == CMDQ_CODE_EOC;
+}
+
 static int cmdq_pkt_finalize(struct cmdq_pkt *pkt)
 {
 	struct cmdq_client *cl = pkt->cl;
 	struct cmdq_instruction inst = { {0} };
 	int err;
 
+	/* do not finalize twice */
+	if (cmdq_pkt_finalized(pkt))
+		return 0;
+
 	/* insert EOC and generate IRQ for each command iteration */
 	inst.op = CMDQ_CODE_EOC;
 	inst.value = CMDQ_EOC_IRQ_EN;
@@ -406,6 +421,32 @@ static int cmdq_pkt_finalize(struct cmdq_pkt *pkt)
 	return err;
 }
 
+int cmdq_pkt_finalize_loop(struct cmdq_pkt *pkt)
+{
+	struct cmdq_client *cl = pkt->cl;
+	struct cmdq_instruction inst = { {0} };
+	int err;
+
+	/* do not finalize twice */
+	if (cmdq_pkt_finalized(pkt))
+		return 0;
+
+	/* insert EOC and generate IRQ for each command iteration */
+	inst.op = CMDQ_CODE_EOC;
+	err = cmdq_pkt_append_command(pkt, inst);
+	if (err < 0)
+		return err;
+
+	/* JUMP abaolute to begin */
+	inst.op = CMDQ_CODE_JUMP;
+	inst.offset = 1;
+	inst.value = pkt->pa_base >> cmdq_mbox_shift(cl->chan);
+	err = cmdq_pkt_append_command(pkt, inst);
+
+	return err;
+}
+EXPORT_SYMBOL(cmdq_pkt_finalize_loop);
+
 static void cmdq_pkt_flush_async_cb(struct cmdq_cb_data data)
 {
 	struct cmdq_pkt *pkt = (struct cmdq_pkt *)data.data;
diff --git a/include/linux/soc/mediatek/mtk-cmdq.h b/include/linux/soc/mediatek/mtk-cmdq.h
index b3474f2..77e8944 100644
--- a/include/linux/soc/mediatek/mtk-cmdq.h
+++ b/include/linux/soc/mediatek/mtk-cmdq.h
@@ -203,6 +203,14 @@ int cmdq_pkt_poll_mask(struct cmdq_pkt *pkt, u8 subsys,
 int cmdq_pkt_assign(struct cmdq_pkt *pkt, u16 reg_idx, u32 value);
 
 /**
+ * cmdq_pkt_finalize_loop() - Append EOC and jump command to loop pkt.
+ * @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
  * @pkt:	the CMDQ packet
-- 
1.7.9.5