mailbox: mtk-cmdq: add gce software ddr enable private data

if gce work control by software, we need set software enable
for MT8186 Soc

there is a handshake flow between gce and ddr hardware,
if not set ddr enable flag of gce, ddr will fall into idle
mode, then gce instructions will not process done.
we need set this flag of gce to tell ddr when gce is idle or busy
controlled by software flow.

0x48[2:0] means control by software
0x48[18:16] means ddr enable
0x48[2:0] is pre-condition of 0x48[18:16].
if we want set 0x48[18:16] ddr enable, 0x48[2:0] must be set at same
time.
and only these bits is useful, other bits is useless bits
Signed-off-by: NYongqiang Niu <yongqiang.niu@mediatek.com>
Reviewed-by: NCK Hu <ck.hu@mediatek.com>
Signed-off-by: NJassi Brar <jaswinder.singh@linaro.org>

drivers/mailbox/mtk-cmdq-mailbox.c

@@ -39,6 +39,7 @@
 
 #define GCE_GCTL_VALUE			0x48
 #define GCE_CTRL_BY_SW				GENMASK(2, 0)
+#define GCE_DDR_EN				GENMASK(18, 16)
 
 #define CMDQ_THR_ACTIVE_SLOT_CYCLES	0x3200
 #define CMDQ_THR_ENABLED		0x1
@@ -81,6 +82,7 @@ struct cmdq {
 	bool			suspended;
 	u8			shift_pa;
 	bool			control_by_sw;
+	bool			sw_ddr_en;
 	u32			gce_num;
 };
 
@@ -88,6 +90,7 @@ struct gce_plat {
 	u32 thread_nr;
 	u8 shift;
 	bool control_by_sw;
+	bool sw_ddr_en;
 	u32 gce_num;
 };
 
@@ -127,10 +130,16 @@ static void cmdq_thread_resume(struct cmdq_thread *thread)
 static void cmdq_init(struct cmdq *cmdq)
 {
 	int i;
+	u32 gctl_regval = 0;
 
 	WARN_ON(clk_bulk_enable(cmdq->gce_num, cmdq->clocks));
 	if (cmdq->control_by_sw)
-		writel(GCE_CTRL_BY_SW, cmdq->base + GCE_GCTL_VALUE);
+		gctl_regval = GCE_CTRL_BY_SW;
+	if (cmdq->sw_ddr_en)
+		gctl_regval |= GCE_DDR_EN;
+
+	if (gctl_regval)
+		writel(gctl_regval, cmdq->base + GCE_GCTL_VALUE);
 
 	writel(CMDQ_THR_ACTIVE_SLOT_CYCLES, cmdq->base + CMDQ_THR_SLOT_CYCLES);
 	for (i = 0; i <= CMDQ_MAX_EVENT; i++)
@@ -545,6 +554,7 @@ static int cmdq_probe(struct platform_device *pdev)
 	cmdq->thread_nr = plat_data->thread_nr;
 	cmdq->shift_pa = plat_data->shift;
 	cmdq->control_by_sw = plat_data->control_by_sw;
+	cmdq->sw_ddr_en = plat_data->sw_ddr_en;
 	cmdq->gce_num = plat_data->gce_num;
 	cmdq->irq_mask = GENMASK(cmdq->thread_nr - 1, 0);
 	err = devm_request_irq(dev, cmdq->irq, cmdq_irq_handler, IRQF_SHARED,