soc: mediatek: mtk-cmdq: Add cmdq_pkt_mem_move() function

Add cmdq_pkt_mem_move() function to support CMDQ user making
an instruction for moving a value from a source address to a
destination address.
Signed-off-by: Jason-JH.Lin <jason-jh.lin@mediatek.com>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Link: https://lore.kernel.org/r/20240307013458.23550-3-jason-jh.lin@mediatek.comSigned-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>

drivers/soc/mediatek/mtk-cmdq-helper.c

@@ -290,6 +290,32 @@ int cmdq_pkt_write_s_mask_value(struct cmdq_pkt *pkt, u8 high_addr_reg_idx,
 }
 EXPORT_SYMBOL(cmdq_pkt_write_s_mask_value);
 
+int cmdq_pkt_mem_move(struct cmdq_pkt *pkt, dma_addr_t src_addr, dma_addr_t dst_addr)
+{
+	const u16 high_addr_reg_idx  = CMDQ_THR_SPR_IDX0;
+	const u16 value_reg_idx = CMDQ_THR_SPR_IDX1;
+	int ret;
+
+	/* read the value of src_addr into high_addr_reg_idx */
+	ret = cmdq_pkt_assign(pkt, high_addr_reg_idx, CMDQ_ADDR_HIGH(src_addr));
+	if (ret < 0)
+		return ret;
+	ret = cmdq_pkt_read_s(pkt, high_addr_reg_idx, CMDQ_ADDR_LOW(src_addr), value_reg_idx);
+	if (ret < 0)
+		return ret;
+
+	/* write the value of value_reg_idx into dst_addr */
+	ret = cmdq_pkt_assign(pkt, high_addr_reg_idx, CMDQ_ADDR_HIGH(dst_addr));
+	if (ret < 0)
+		return ret;
+	ret = cmdq_pkt_write_s(pkt, high_addr_reg_idx, CMDQ_ADDR_LOW(dst_addr), value_reg_idx);
+	if (ret < 0)
+		return ret;
+
+	return 0;
+}
+EXPORT_SYMBOL(cmdq_pkt_mem_move);
+
 int cmdq_pkt_wfe(struct cmdq_pkt *pkt, u16 event, bool clear)
 {
 	struct cmdq_instruction inst = { {0} };

include/linux/soc/mediatek/mtk-cmdq.h

@@ -184,6 +184,18 @@ int cmdq_pkt_write_s_value(struct cmdq_pkt *pkt, u8 high_addr_reg_idx,
 int cmdq_pkt_write_s_mask_value(struct cmdq_pkt *pkt, u8 high_addr_reg_idx,
 				u16 addr_low, u32 value, u32 mask);
 
+/**
+ * cmdq_pkt_mem_move() - append memory move command to the CMDQ packet
+ * @pkt:	the CMDQ packet
+ * @src_addr:	source address
+ * @dst_addr:	destination address
+ *
+ * Appends a CMDQ command to copy the value found in `src_addr` to `dst_addr`.
+ *
+ * Return: 0 for success; else the error code is returned
+ */
+int cmdq_pkt_mem_move(struct cmdq_pkt *pkt, dma_addr_t src_addr, dma_addr_t dst_addr);
+
 /**
  * cmdq_pkt_wfe() - append wait for event command to the CMDQ packet
  * @pkt:	the CMDQ packet