media: ti-vpe: cal: Align DPHY init sequence with docs

The current CSI2 DPHY initialization sequence although
functional does not match with the documented sequence
in the Technical Reference Manual.

This may affect capture re-startability in stop/start
situations.
Signed-off-by: Benoit Parrot <bparrot@ti.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

drivers/media/platform/ti-vpe/cal.c

@@ -686,29 +686,76 @@ static void disable_irqs(struct cal_ctx *ctx)
 	reg_write(ctx->dev, CAL_CSI2_VC_IRQENABLE(1), 0);
 }
 
-static void csi2_init(struct cal_ctx *ctx)
+static void csi2_phy_config(struct cal_ctx *ctx);
+
+static void csi2_phy_init(struct cal_ctx *ctx)
 {
 	int i;
 	u32 val;
 
+	/* Steps
+	 *  1. Configure D-PHY mode and enable required lanes
+	 *  2. Reset complex IO - Wait for completion of reset
+	 *          Note if the external sensor is not sending byte clock,
+	 *          the reset will timeout
+	 *  3 Program Stop States
+	 *      A. Program THS_TERM, THS_SETTLE, etc... Timings parameters
+	 *              in terms of DDR clock periods
+	 *      B. Enable stop state transition timeouts
+	 *  4.Force FORCERXMODE
+	 *      D. Enable pull down using pad control
+	 *      E. Power up PHY
+	 *      F. Wait for power up completion
+	 *      G. Wait for all enabled lane to reach stop state
+	 *      H. Disable pull down using pad control
+	 */
+
+	/* 1. Configure D-PHY mode and enable required lanes */
+	camerarx_phy_enable(ctx);
+
+	/* 2. Reset complex IO - Do not wait for reset completion */
+	val = reg_read(ctx->dev, CAL_CSI2_COMPLEXIO_CFG(ctx->csi2_port));
+	set_field(&val, CAL_CSI2_COMPLEXIO_CFG_RESET_CTRL_OPERATIONAL,
+		  CAL_CSI2_COMPLEXIO_CFG_RESET_CTRL_MASK);
+	reg_write(ctx->dev, CAL_CSI2_COMPLEXIO_CFG(ctx->csi2_port), val);
+	ctx_dbg(3, ctx, "CAL_CSI2_COMPLEXIO_CFG(%d) = 0x%08x De-assert Complex IO Reset\n",
+		ctx->csi2_port,
+		reg_read(ctx->dev, CAL_CSI2_COMPLEXIO_CFG(ctx->csi2_port)));
+
+	/* Dummy read to allow SCP to complete */
+	val = reg_read(ctx->dev, CAL_CSI2_COMPLEXIO_CFG(ctx->csi2_port));
+
+	/* 3.A. Program Phy Timing Parameters */
+	csi2_phy_config(ctx);
+
+	/* 3.B. Program Stop States */
 	val = reg_read(ctx->dev, CAL_CSI2_TIMING(ctx->csi2_port));
-	set_field(&val, CAL_GEN_ENABLE,
-		  CAL_CSI2_TIMING_FORCE_RX_MODE_IO1_MASK);
 	set_field(&val, CAL_GEN_ENABLE,
 		  CAL_CSI2_TIMING_STOP_STATE_X16_IO1_MASK);
 	set_field(&val, CAL_GEN_DISABLE,
 		  CAL_CSI2_TIMING_STOP_STATE_X4_IO1_MASK);
 	set_field(&val, 407, CAL_CSI2_TIMING_STOP_STATE_COUNTER_IO1_MASK);
 	reg_write(ctx->dev, CAL_CSI2_TIMING(ctx->csi2_port), val);
-	ctx_dbg(3, ctx, "CAL_CSI2_TIMING(%d) = 0x%08x\n", ctx->csi2_port,
+	ctx_dbg(3, ctx, "CAL_CSI2_TIMING(%d) = 0x%08x Stop States\n",
+		ctx->csi2_port,
+		reg_read(ctx->dev, CAL_CSI2_TIMING(ctx->csi2_port)));
+
+	/* 4. Force FORCERXMODE */
+	val = reg_read(ctx->dev, CAL_CSI2_TIMING(ctx->csi2_port));
+	set_field(&val, CAL_GEN_ENABLE,
+		  CAL_CSI2_TIMING_FORCE_RX_MODE_IO1_MASK);
+	reg_write(ctx->dev, CAL_CSI2_TIMING(ctx->csi2_port), val);
+	ctx_dbg(3, ctx, "CAL_CSI2_TIMING(%d) = 0x%08x Force RXMODE\n",
+		ctx->csi2_port,
 		reg_read(ctx->dev, CAL_CSI2_TIMING(ctx->csi2_port)));
 
+	/* E. Power up the PHY using the complex IO */
 	val = reg_read(ctx->dev, CAL_CSI2_COMPLEXIO_CFG(ctx->csi2_port));
-	set_field(&val, CAL_CSI2_COMPLEXIO_CFG_RESET_CTRL_OPERATIONAL,
-		  CAL_CSI2_COMPLEXIO_CFG_RESET_CTRL_MASK);
 	set_field(&val, CAL_CSI2_COMPLEXIO_CFG_PWR_CMD_STATE_ON,
 		  CAL_CSI2_COMPLEXIO_CFG_PWR_CMD_MASK);
 	reg_write(ctx->dev, CAL_CSI2_COMPLEXIO_CFG(ctx->csi2_port), val);
+
+	/* F. Wait for power up completion */
 	for (i = 0; i < 10; i++) {
 		if (reg_read_field(ctx->dev,
 				   CAL_CSI2_COMPLEXIO_CFG(ctx->csi2_port),
@@ -717,18 +764,104 @@ static void csi2_init(struct cal_ctx *ctx)
 			break;
 		usleep_range(1000, 1100);
 	}
-	ctx_dbg(3, ctx, "CAL_CSI2_COMPLEXIO_CFG(%d) = 0x%08x\n", ctx->csi2_port,
-		reg_read(ctx->dev, CAL_CSI2_COMPLEXIO_CFG(ctx->csi2_port)));
+	ctx_dbg(3, ctx, "CAL_CSI2_COMPLEXIO_CFG(%d) = 0x%08x Powered UP %s\n",
+		ctx->csi2_port,
+		reg_read(ctx->dev, CAL_CSI2_COMPLEXIO_CFG(ctx->csi2_port)),
+		(i >= 10) ? "(timeout)" : "");
+}
 
-	val = reg_read(ctx->dev, CAL_CTRL);
-	set_field(&val, CAL_CTRL_BURSTSIZE_BURST128, CAL_CTRL_BURSTSIZE_MASK);
-	set_field(&val, 0xF, CAL_CTRL_TAGCNT_MASK);
-	set_field(&val, CAL_CTRL_POSTED_WRITES_NONPOSTED,
-		  CAL_CTRL_POSTED_WRITES_MASK);
-	set_field(&val, 0xFF, CAL_CTRL_MFLAGL_MASK);
-	set_field(&val, 0xFF, CAL_CTRL_MFLAGH_MASK);
-	reg_write(ctx->dev, CAL_CTRL, val);
-	ctx_dbg(3, ctx, "CAL_CTRL = 0x%08x\n", reg_read(ctx->dev, CAL_CTRL));
+static void csi2_wait_for_phy(struct cal_ctx *ctx)
+{
+	int i;
+
+	/* Steps
+	 *  2. Wait for completion of reset
+	 *          Note if the external sensor is not sending byte clock,
+	 *          the reset will timeout
+	 *  4.Force FORCERXMODE
+	 *      G. Wait for all enabled lane to reach stop state
+	 *      H. Disable pull down using pad control
+	 */
+
+	/* 2. Wait for reset completion */
+	for (i = 0; i < 250; i++) {
+		if (reg_read_field(ctx->dev,
+				   CAL_CSI2_COMPLEXIO_CFG(ctx->csi2_port),
+				   CAL_CSI2_COMPLEXIO_CFG_RESET_DONE_MASK) ==
+		    CAL_CSI2_COMPLEXIO_CFG_RESET_DONE_RESETCOMPLETED)
+			break;
+		usleep_range(1000, 1100);
+	}
+	ctx_dbg(3, ctx, "CAL_CSI2_COMPLEXIO_CFG(%d) = 0x%08x Complex IO Reset Done (%d) %s\n",
+		ctx->csi2_port,
+		reg_read(ctx->dev, CAL_CSI2_COMPLEXIO_CFG(ctx->csi2_port)), i,
+		(i >= 250) ? "(timeout)" : "");
+
+	/* 4. G. Wait for all enabled lane to reach stop state */
+	for (i = 0; i < 10; i++) {
+		if (reg_read_field(ctx->dev,
+				   CAL_CSI2_TIMING(ctx->csi2_port),
+				   CAL_CSI2_TIMING_FORCE_RX_MODE_IO1_MASK) ==
+		    CAL_GEN_DISABLE)
+			break;
+		usleep_range(1000, 1100);
+	}
+	ctx_dbg(3, ctx, "CAL_CSI2_TIMING(%d) = 0x%08x Stop State Reached %s\n",
+		ctx->csi2_port,
+		reg_read(ctx->dev, CAL_CSI2_TIMING(ctx->csi2_port)),
+		(i >= 10) ? "(timeout)" : "");
+
+	ctx_dbg(1, ctx, "CSI2_%d_REG1 = 0x%08x (Bit(31,28) should be set!)\n",
+		(ctx->csi2_port - 1), reg_read(ctx->cc, CAL_CSI2_PHY_REG1));
+}
+
+static void csi2_phy_deinit(struct cal_ctx *ctx)
+{
+	int i;
+	u32 val;
+
+	/* Power down the PHY using the complex IO */
+	val = reg_read(ctx->dev, CAL_CSI2_COMPLEXIO_CFG(ctx->csi2_port));
+	set_field(&val, CAL_CSI2_COMPLEXIO_CFG_PWR_CMD_STATE_OFF,
+		  CAL_CSI2_COMPLEXIO_CFG_PWR_CMD_MASK);
+	reg_write(ctx->dev, CAL_CSI2_COMPLEXIO_CFG(ctx->csi2_port), val);
+
+	/* Wait for power down completion */
+	for (i = 0; i < 10; i++) {
+		if (reg_read_field(ctx->dev,
+				   CAL_CSI2_COMPLEXIO_CFG(ctx->csi2_port),
+				   CAL_CSI2_COMPLEXIO_CFG_PWR_STATUS_MASK) ==
+		    CAL_CSI2_COMPLEXIO_CFG_PWR_STATUS_STATE_OFF)
+			break;
+		usleep_range(1000, 1100);
+	}
+	ctx_dbg(3, ctx, "CAL_CSI2_COMPLEXIO_CFG(%d) = 0x%08x Powered Down %s\n",
+		ctx->csi2_port,
+		reg_read(ctx->dev, CAL_CSI2_COMPLEXIO_CFG(ctx->csi2_port)),
+		(i >= 10) ? "(timeout)" : "");
+
+	/* Assert Comple IO Reset */
+	val = reg_read(ctx->dev, CAL_CSI2_COMPLEXIO_CFG(ctx->csi2_port));
+	set_field(&val, CAL_CSI2_COMPLEXIO_CFG_RESET_CTRL,
+		  CAL_CSI2_COMPLEXIO_CFG_RESET_CTRL_MASK);
+	reg_write(ctx->dev, CAL_CSI2_COMPLEXIO_CFG(ctx->csi2_port), val);
+
+	/* Wait for power down completion */
+	for (i = 0; i < 10; i++) {
+		if (reg_read_field(ctx->dev,
+				   CAL_CSI2_COMPLEXIO_CFG(ctx->csi2_port),
+				   CAL_CSI2_COMPLEXIO_CFG_RESET_DONE_MASK) ==
+		    CAL_CSI2_COMPLEXIO_CFG_RESET_DONE_RESETONGOING)
+			break;
+		usleep_range(1000, 1100);
+	}
+	ctx_dbg(3, ctx, "CAL_CSI2_COMPLEXIO_CFG(%d) = 0x%08x Complex IO in Reset (%d) %s\n",
+		ctx->csi2_port,
+		reg_read(ctx->dev, CAL_CSI2_COMPLEXIO_CFG(ctx->csi2_port)), i,
+		(i >= 10) ? "(timeout)" : "");
+
+	/* Disable the phy */
+	camerarx_phy_disable(ctx);
 }
 
 static void csi2_lane_config(struct cal_ctx *ctx)
@@ -891,6 +1024,16 @@ static void cal_wr_dma_config(struct cal_ctx *ctx,
 	reg_write(ctx->dev, CAL_WR_DMA_XSIZE(ctx->csi2_port), val);
 	ctx_dbg(3, ctx, "CAL_WR_DMA_XSIZE(%d) = 0x%08x\n", ctx->csi2_port,
 		reg_read(ctx->dev, CAL_WR_DMA_XSIZE(ctx->csi2_port)));
+
+	val = reg_read(ctx->dev, CAL_CTRL);
+	set_field(&val, CAL_CTRL_BURSTSIZE_BURST128, CAL_CTRL_BURSTSIZE_MASK);
+	set_field(&val, 0xF, CAL_CTRL_TAGCNT_MASK);
+	set_field(&val, CAL_CTRL_POSTED_WRITES_NONPOSTED,
+		  CAL_CTRL_POSTED_WRITES_MASK);
+	set_field(&val, 0xFF, CAL_CTRL_MFLAGL_MASK);
+	set_field(&val, 0xFF, CAL_CTRL_MFLAGH_MASK);
+	reg_write(ctx->dev, CAL_CTRL, val);
+	ctx_dbg(3, ctx, "CAL_CTRL = 0x%08x\n", reg_read(ctx->dev, CAL_CTRL));
 }
 
 static void cal_wr_dma_addr(struct cal_ctx *ctx, unsigned int dmaaddr)
@@ -1463,17 +1606,14 @@ static int cal_start_streaming(struct vb2_queue *vq, unsigned int count)
 
 	cal_runtime_get(ctx->dev);
 
-	enable_irqs(ctx);
-	camerarx_phy_enable(ctx);
-	csi2_init(ctx);
-	csi2_phy_config(ctx);
-	csi2_lane_config(ctx);
 	csi2_ctx_config(ctx);
 	pix_proc_config(ctx);
 	cal_wr_dma_config(ctx, ctx->v_fmt.fmt.pix.bytesperline,
 			  ctx->v_fmt.fmt.pix.height);
-	cal_wr_dma_addr(ctx, addr);
-	csi2_ppi_enable(ctx);
+	csi2_lane_config(ctx);
+
+	enable_irqs(ctx);
+	csi2_phy_init(ctx);
 
 	ret = v4l2_subdev_call(ctx->sensor, video, s_stream, 1);
 	if (ret) {
@@ -1482,6 +1622,10 @@ static int cal_start_streaming(struct vb2_queue *vq, unsigned int count)
 		goto err;
 	}
 
+	csi2_wait_for_phy(ctx);
+	cal_wr_dma_addr(ctx, addr);
+	csi2_ppi_enable(ctx);
+
 	if (debug >= 4)
 		cal_quickdump_regs(ctx->dev);
 
@@ -1502,11 +1646,12 @@ static void cal_stop_streaming(struct vb2_queue *vq)
 	struct cal_buffer *buf, *tmp;
 	unsigned long flags;
 
-	if (v4l2_subdev_call(ctx->sensor, video, s_stream, 0))
-		ctx_err(ctx, "stream off failed in subdev\n");
-
 	csi2_ppi_disable(ctx);
 	disable_irqs(ctx);
+	csi2_phy_deinit(ctx);
+
+	if (v4l2_subdev_call(ctx->sensor, video, s_stream, 0))
+		ctx_err(ctx, "stream off failed in subdev\n");
 
 	/* Release all active buffers */
 	spin_lock_irqsave(&ctx->slock, flags);