From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Date: Thu, 1 Mar 2018 14:09:18 -0600 From: Benoit Parrot Subject: Re: [PATCH v8 2/2] v4l: cadence: Add Cadence MIPI-CSI2 RX driver Message-ID: <20180301200918.GL6807@ti.com> References: <20180215133335.9335-1-maxime.ripard@bootlin.com> <20180215133335.9335-3-maxime.ripard@bootlin.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Disposition: inline In-Reply-To: <20180215133335.9335-3-maxime.ripard@bootlin.com> To: Maxime Ripard Cc: Mauro Carvalho Chehab , Mark Rutland , Rob Herring , Laurent Pinchart , linux-media@vger.kernel.org, devicetree@vger.kernel.org, Richard Sproul , Alan Douglas , Steve Creaney , Thomas Petazzoni , Boris Brezillon , Niklas =?iso-8859-1?Q?S=F6derlund?= , Hans Verkuil , Sakari Ailus , nm@ti.com, Simon Hatliff List-ID: Maxime, Thank you for the patch. Maxime Ripard wrote on Thu [2018-Feb-15 14:33:35 +0100]: > The Cadence CSI-2 RX Controller is an hardware block meant to be used as a > bridge between a CSI-2 bus and pixel grabbers. > > It supports operating with internal or external D-PHY, with up to 4 lanes, > or without any D-PHY. The current code only supports the latter case. > > It also support dynamic mapping of the CSI-2 virtual channels to the > associated pixel grabbers, but that isn't allowed at the moment either. > > Acked-by: Sakari Ailus > Signed-off-by: Maxime Ripard > --- > drivers/media/platform/Kconfig | 1 + > drivers/media/platform/Makefile | 2 + > drivers/media/platform/cadence/Kconfig | 17 + > drivers/media/platform/cadence/Makefile | 1 + > drivers/media/platform/cadence/cdns-csi2rx.c | 499 +++++++++++++++++++++++++++ > 5 files changed, 520 insertions(+) > create mode 100644 drivers/media/platform/cadence/Kconfig > create mode 100644 drivers/media/platform/cadence/Makefile > create mode 100644 drivers/media/platform/cadence/cdns-csi2rx.c > > diff --git a/drivers/media/platform/Kconfig b/drivers/media/platform/Kconfig > index 614fbef08ddc..c001b646d441 100644 > --- a/drivers/media/platform/Kconfig > +++ b/drivers/media/platform/Kconfig > @@ -26,6 +26,7 @@ config VIDEO_VIA_CAMERA > # > # Platform multimedia device configuration > # > +source "drivers/media/platform/cadence/Kconfig" > > source "drivers/media/platform/davinci/Kconfig" > > diff --git a/drivers/media/platform/Makefile b/drivers/media/platform/Makefile > index 7f3080437be6..3d29082fcf72 100644 > --- a/drivers/media/platform/Makefile > +++ b/drivers/media/platform/Makefile > @@ -3,6 +3,8 @@ > # Makefile for the video capture/playback device drivers. > # > > +obj-$(CONFIG_VIDEO_CADENCE) += cadence/ > + > obj-$(CONFIG_VIDEO_M32R_AR_M64278) += arv.o > > obj-$(CONFIG_VIDEO_VIA_CAMERA) += via-camera.o > diff --git a/drivers/media/platform/cadence/Kconfig b/drivers/media/platform/cadence/Kconfig > new file mode 100644 > index 000000000000..18f061e5cbd1 > --- /dev/null > +++ b/drivers/media/platform/cadence/Kconfig > @@ -0,0 +1,17 @@ > +config VIDEO_CADENCE > + bool "Cadence Video Devices" > + > +if VIDEO_CADENCE > + > +config VIDEO_CADENCE_CSI2RX > + tristate "Cadence MIPI-CSI2 RX Controller" > + depends on MEDIA_CONTROLLER > + depends on VIDEO_V4L2_SUBDEV_API > + select V4L2_FWNODE > + help > + Support for the Cadence MIPI CSI2 Receiver controller. > + > + To compile this driver as a module, choose M here: the module will be > + called cdns-csi2rx. > + > +endif > diff --git a/drivers/media/platform/cadence/Makefile b/drivers/media/platform/cadence/Makefile > new file mode 100644 > index 000000000000..99a4086b7448 > --- /dev/null > +++ b/drivers/media/platform/cadence/Makefile > @@ -0,0 +1 @@ > +obj-$(CONFIG_VIDEO_CADENCE_CSI2RX) += cdns-csi2rx.o > diff --git a/drivers/media/platform/cadence/cdns-csi2rx.c b/drivers/media/platform/cadence/cdns-csi2rx.c > new file mode 100644 > index 000000000000..99662e1a536b > --- /dev/null > +++ b/drivers/media/platform/cadence/cdns-csi2rx.c > @@ -0,0 +1,499 @@ > +// SPDX-License-Identifier: GPL-2.0+ > +/* > + * Driver for Cadence MIPI-CSI2 RX Controller v1.3 > + * > + * Copyright (C) 2017 Cadence Design Systems Inc. > + */ > + > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > + > +#include > +#include > +#include > +#include > + > +#define CSI2RX_DEVICE_CFG_REG 0x000 > + > +#define CSI2RX_SOFT_RESET_REG 0x004 > +#define CSI2RX_SOFT_RESET_PROTOCOL BIT(1) > +#define CSI2RX_SOFT_RESET_FRONT BIT(0) > + > +#define CSI2RX_STATIC_CFG_REG 0x008 > +#define CSI2RX_STATIC_CFG_DLANE_MAP(llane, plane) ((plane) << (16 + (llane) * 4)) > +#define CSI2RX_STATIC_CFG_LANES_MASK GENMASK(11, 8) > + > +#define CSI2RX_STREAM_BASE(n) (((n) + 1) * 0x100) > + > +#define CSI2RX_STREAM_CTRL_REG(n) (CSI2RX_STREAM_BASE(n) + 0x000) > +#define CSI2RX_STREAM_CTRL_START BIT(0) > + > +#define CSI2RX_STREAM_DATA_CFG_REG(n) (CSI2RX_STREAM_BASE(n) + 0x008) > +#define CSI2RX_STREAM_DATA_CFG_EN_VC_SELECT BIT(31) > +#define CSI2RX_STREAM_DATA_CFG_VC_SELECT(n) BIT((n) + 16) > + > +#define CSI2RX_STREAM_CFG_REG(n) (CSI2RX_STREAM_BASE(n) + 0x00c) > +#define CSI2RX_STREAM_CFG_FIFO_MODE_LARGE_BUF (1 << 8) > + > +#define CSI2RX_LANES_MAX 4 > +#define CSI2RX_STREAMS_MAX 4 > + > +enum csi2rx_pads { > + CSI2RX_PAD_SINK, > + CSI2RX_PAD_SOURCE_STREAM0, > + CSI2RX_PAD_SOURCE_STREAM1, > + CSI2RX_PAD_SOURCE_STREAM2, > + CSI2RX_PAD_SOURCE_STREAM3, > + CSI2RX_PAD_MAX, > +}; > + > +struct csi2rx_priv { > + struct device *dev; > + unsigned int count; > + > + /* > + * Used to prevent race conditions between multiple, > + * concurrent calls to start and stop. > + */ > + struct mutex lock; > + > + void __iomem *base; > + struct clk *sys_clk; > + struct clk *p_clk; > + struct clk *pixel_clk[CSI2RX_STREAMS_MAX]; > + struct phy *dphy; > + > + u8 lanes[CSI2RX_LANES_MAX]; > + u8 num_lanes; > + u8 max_lanes; > + u8 max_streams; > + bool has_internal_dphy; > + > + struct v4l2_subdev subdev; > + struct v4l2_async_notifier notifier; > + struct media_pad pads[CSI2RX_PAD_MAX]; > + > + /* Remote source */ > + struct v4l2_async_subdev asd; > + struct v4l2_subdev *source_subdev; > + int source_pad; > +}; > + > +static inline > +struct csi2rx_priv *v4l2_subdev_to_csi2rx(struct v4l2_subdev *subdev) > +{ > + return container_of(subdev, struct csi2rx_priv, subdev); > +} > + > +static void csi2rx_reset(struct csi2rx_priv *csi2rx) > +{ > + writel(CSI2RX_SOFT_RESET_PROTOCOL | CSI2RX_SOFT_RESET_FRONT, > + csi2rx->base + CSI2RX_SOFT_RESET_REG); > + > + udelay(10); > + > + writel(0, csi2rx->base + CSI2RX_SOFT_RESET_REG); > +} > + > +static int csi2rx_start(struct csi2rx_priv *csi2rx) > +{ > + unsigned int i; > + unsigned long lanes_used = 0; > + u32 reg; > + int ret; > + > + ret = clk_prepare_enable(csi2rx->p_clk); > + if (ret) > + return ret; > + > + csi2rx_reset(csi2rx); > + > + reg = csi2rx->num_lanes << 8; > + for (i = 0; i < csi2rx->num_lanes; i++) { > + reg |= CSI2RX_STATIC_CFG_DLANE_MAP(i, csi2rx->lanes[i]); > + set_bit(csi2rx->lanes[i], &lanes_used); > + } > + > + /* > + * Even the unused lanes need to be mapped. In order to avoid > + * to map twice to the same physical lane, keep the lanes used > + * in the previous loop, and only map unused physical lanes to > + * the rest of our logical lanes. > + */ > + for (i = csi2rx->num_lanes; i < csi2rx->max_lanes; i++) { > + unsigned int idx = find_first_zero_bit(&lanes_used, > + sizeof(lanes_used)); > + set_bit(idx, &lanes_used); > + reg |= CSI2RX_STATIC_CFG_DLANE_MAP(i, i + 1); > + } > + > + writel(reg, csi2rx->base + CSI2RX_STATIC_CFG_REG); > + > + ret = v4l2_subdev_call(csi2rx->source_subdev, video, s_stream, true); > + if (ret) > + goto err_disable_pclk; > + > + /* > + * Create a static mapping between the CSI virtual channels > + * and the output stream. > + * > + * This should be enhanced, but v4l2 lacks the support for > + * changing that mapping dynamically. > + * > + * We also cannot enable and disable independant streams here, > + * hence the reference counting. > + */ > + for (i = 0; i < csi2rx->max_streams; i++) { > + ret = clk_prepare_enable(csi2rx->pixel_clk[i]); > + if (ret) > + goto err_disable_pixclk; > + > + writel(CSI2RX_STREAM_CFG_FIFO_MODE_LARGE_BUF, > + csi2rx->base + CSI2RX_STREAM_CFG_REG(i)); > + > + writel(CSI2RX_STREAM_DATA_CFG_EN_VC_SELECT | > + CSI2RX_STREAM_DATA_CFG_VC_SELECT(i), > + csi2rx->base + CSI2RX_STREAM_DATA_CFG_REG(i)); > + > + writel(CSI2RX_STREAM_CTRL_START, > + csi2rx->base + CSI2RX_STREAM_CTRL_REG(i)); > + } > + > + ret = clk_prepare_enable(csi2rx->sys_clk); > + if (ret) > + goto err_disable_pixclk; > + > + clk_disable_unprepare(csi2rx->p_clk); > + > + return 0; > + > +err_disable_pixclk: > + for (; i >= 0; i--) > + clk_disable_unprepare(csi2rx->pixel_clk[i]); > + > +err_disable_pclk: > + clk_disable_unprepare(csi2rx->p_clk); > + > + return ret; > +} > + > +static int csi2rx_stop(struct csi2rx_priv *csi2rx) > +{ > + unsigned int i; > + > + clk_prepare_enable(csi2rx->p_clk); > + clk_disable_unprepare(csi2rx->sys_clk); > + > + for (i = 0; i < csi2rx->max_streams; i++) { > + writel(0, csi2rx->base + CSI2RX_STREAM_CTRL_REG(i)); > + > + clk_disable_unprepare(csi2rx->pixel_clk[i]); > + } > + > + clk_disable_unprepare(csi2rx->p_clk); > + > + return v4l2_subdev_call(csi2rx->source_subdev, video, s_stream, false); > +} > + > +static int csi2rx_s_stream(struct v4l2_subdev *subdev, int enable) > +{ > + struct csi2rx_priv *csi2rx = v4l2_subdev_to_csi2rx(subdev); > + int ret = 0; > + > + mutex_lock(&csi2rx->lock); > + > + if (enable) { > + /* > + * If we're not the first users, there's no need to > + * enable the whole controller. > + */ > + if (!csi2rx->count) { > + ret = csi2rx_start(csi2rx); > + if (ret) > + goto out; > + } > + > + csi2rx->count++; > + } else { > + csi2rx->count--; > + > + /* > + * Let the last user turn off the lights. > + */ > + if (!csi2rx->count) { > + ret = csi2rx_stop(csi2rx); > + if (ret) > + goto out; > + } > + } > + > +out: > + mutex_unlock(&csi2rx->lock); > + return ret; > +} > + > +static const struct v4l2_subdev_video_ops csi2rx_video_ops = { > + .s_stream = csi2rx_s_stream, > +}; > + > +static const struct v4l2_subdev_ops csi2rx_subdev_ops = { > + .video = &csi2rx_video_ops, > +}; > + > +static int csi2rx_async_bound(struct v4l2_async_notifier *notifier, > + struct v4l2_subdev *s_subdev, > + struct v4l2_async_subdev *asd) > +{ > + struct v4l2_subdev *subdev = notifier->sd; > + struct csi2rx_priv *csi2rx = v4l2_subdev_to_csi2rx(subdev); > + > + csi2rx->source_pad = media_entity_get_fwnode_pad(&s_subdev->entity, > + s_subdev->fwnode, > + MEDIA_PAD_FL_SOURCE); > + if (csi2rx->source_pad < 0) { > + dev_err(csi2rx->dev, "Couldn't find output pad for subdev %s\n", > + s_subdev->name); > + return csi2rx->source_pad; > + } > + > + csi2rx->source_subdev = s_subdev; > + > + dev_dbg(csi2rx->dev, "Bound %s pad: %d\n", s_subdev->name, > + csi2rx->source_pad); > + > + return media_create_pad_link(&csi2rx->source_subdev->entity, > + csi2rx->source_pad, > + &csi2rx->subdev.entity, 0, > + MEDIA_LNK_FL_ENABLED | > + MEDIA_LNK_FL_IMMUTABLE); > +} > + > +static const struct v4l2_async_notifier_operations csi2rx_notifier_ops = { > + .bound = csi2rx_async_bound, > +}; > + > +static int csi2rx_get_resources(struct csi2rx_priv *csi2rx, > + struct platform_device *pdev) > +{ > + struct resource *res; > + unsigned char i; > + u32 dev_cfg; > + > + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); > + csi2rx->base = devm_ioremap_resource(&pdev->dev, res); > + if (IS_ERR(csi2rx->base)) > + return PTR_ERR(csi2rx->base); > + > + csi2rx->sys_clk = devm_clk_get(&pdev->dev, "sys_clk"); > + if (IS_ERR(csi2rx->sys_clk)) { > + dev_err(&pdev->dev, "Couldn't get sys clock\n"); > + return PTR_ERR(csi2rx->sys_clk); > + } > + > + csi2rx->p_clk = devm_clk_get(&pdev->dev, "p_clk"); > + if (IS_ERR(csi2rx->p_clk)) { > + dev_err(&pdev->dev, "Couldn't get P clock\n"); > + return PTR_ERR(csi2rx->p_clk); > + } > + > + csi2rx->dphy = devm_phy_optional_get(&pdev->dev, "dphy"); > + if (IS_ERR(csi2rx->dphy)) { > + dev_err(&pdev->dev, "Couldn't get external D-PHY\n"); > + return PTR_ERR(csi2rx->dphy); > + } > + > + /* > + * FIXME: Once we'll have external D-PHY support, the check > + * will need to be removed. > + */ > + if (csi2rx->dphy) { > + dev_err(&pdev->dev, "External D-PHY not supported yet\n"); > + return -EINVAL; > + } > + > + clk_prepare_enable(csi2rx->p_clk); > + dev_cfg = readl(csi2rx->base + CSI2RX_DEVICE_CFG_REG); > + clk_disable_unprepare(csi2rx->p_clk); > + > + csi2rx->max_lanes = dev_cfg & 7; > + if (csi2rx->max_lanes > CSI2RX_LANES_MAX) { > + dev_err(&pdev->dev, "Invalid number of lanes: %u\n", > + csi2rx->max_lanes); > + return -EINVAL; > + } > + > + csi2rx->max_streams = (dev_cfg >> 4) & 7; > + if (csi2rx->max_streams > CSI2RX_STREAMS_MAX) { > + dev_err(&pdev->dev, "Invalid number of streams: %u\n", > + csi2rx->max_streams); > + return -EINVAL; > + } > + > + csi2rx->has_internal_dphy = dev_cfg & BIT(3) ? true : false; > + > + /* > + * FIXME: Once we'll have internal D-PHY support, the check > + * will need to be removed. > + */ > + if (csi2rx->has_internal_dphy) { > + dev_err(&pdev->dev, "Internal D-PHY not supported yet\n"); > + return -EINVAL; > + } As one of the more critical thing is usually how the CSI2 Receiver interact with a DPHY when can we expect this part of the driver to be implemented? Regards, Benoit [snip]