[PATCH 07/11] drm/vc4: Add DSI driver

Daniel Vetter daniel at ffwll.ch
Tue Jan 31 11:52:31 PST 2017


On Wed, Dec 14, 2016 at 11:46:17AM -0800, Eric Anholt wrote:
> The DSI0 and DSI1 blocks on the 2835 are related hardware blocks.
> Some registers move around, and the featureset is slightly different,
> as DSI1 (the 4-lane DSI) is a later version of the hardware block.
> This driver doesn't yet enable DSI0, since we don't have any hardware
> to test against, but it does put a lot of the register definitions and
> code in place.
> 
> Signed-off-by: Eric Anholt <eric at anholt.net>

Looks all neat, below a few semi-random ideas.

Acked-by: Daniel Vetter <daniel.vetter at ffwll.ch>
> ---
>  drivers/gpu/drm/vc4/Kconfig       |    2 +
>  drivers/gpu/drm/vc4/Makefile      |    1 +
>  drivers/gpu/drm/vc4/vc4_debugfs.c |    1 +
>  drivers/gpu/drm/vc4/vc4_drv.c     |    1 +
>  drivers/gpu/drm/vc4/vc4_drv.h     |    5 +
>  drivers/gpu/drm/vc4/vc4_dsi.c     | 1725 +++++++++++++++++++++++++++++++++++++
>  6 files changed, 1735 insertions(+)
>  create mode 100644 drivers/gpu/drm/vc4/vc4_dsi.c
> 
> diff --git a/drivers/gpu/drm/vc4/Kconfig b/drivers/gpu/drm/vc4/Kconfig
> index e53df59cb139..e1517d07cb7d 100644
> --- a/drivers/gpu/drm/vc4/Kconfig
> +++ b/drivers/gpu/drm/vc4/Kconfig
> @@ -2,10 +2,12 @@ config DRM_VC4
>  	tristate "Broadcom VC4 Graphics"
>  	depends on ARCH_BCM2835 || COMPILE_TEST
>  	depends on DRM
> +	depends on COMMON_CLK
>  	select DRM_KMS_HELPER
>  	select DRM_KMS_CMA_HELPER
>  	select DRM_GEM_CMA_HELPER
>  	select DRM_PANEL
> +	select DRM_MIPI_DSI
>  	help
>  	  Choose this option if you have a system that has a Broadcom
>  	  VC4 GPU, such as the Raspberry Pi or other BCM2708/BCM2835.
> diff --git a/drivers/gpu/drm/vc4/Makefile b/drivers/gpu/drm/vc4/Makefile
> index 7757f69a8a77..61f45d122bd0 100644
> --- a/drivers/gpu/drm/vc4/Makefile
> +++ b/drivers/gpu/drm/vc4/Makefile
> @@ -8,6 +8,7 @@ vc4-y := \
>  	vc4_crtc.o \
>  	vc4_drv.o \
>  	vc4_dpi.o \
> +	vc4_dsi.o \
>  	vc4_kms.o \
>  	vc4_gem.o \
>  	vc4_hdmi.o \
> diff --git a/drivers/gpu/drm/vc4/vc4_debugfs.c b/drivers/gpu/drm/vc4/vc4_debugfs.c
> index caf817bac885..3ca476c6e057 100644
> --- a/drivers/gpu/drm/vc4/vc4_debugfs.c
> +++ b/drivers/gpu/drm/vc4/vc4_debugfs.c
> @@ -18,6 +18,7 @@
>  static const struct drm_info_list vc4_debugfs_list[] = {
>  	{"bo_stats", vc4_bo_stats_debugfs, 0},
>  	{"dpi_regs", vc4_dpi_debugfs_regs, 0},
> +	{"dsi1_regs", vc4_dsi_debugfs_regs, 0, (void *)(uintptr_t)1},
>  	{"hdmi_regs", vc4_hdmi_debugfs_regs, 0},
>  	{"vec_regs", vc4_vec_debugfs_regs, 0},
>  	{"hvs_regs", vc4_hvs_debugfs_regs, 0},
> diff --git a/drivers/gpu/drm/vc4/vc4_drv.c b/drivers/gpu/drm/vc4/vc4_drv.c
> index bdab333979dc..2d2edc7dcf4a 100644
> --- a/drivers/gpu/drm/vc4/vc4_drv.c
> +++ b/drivers/gpu/drm/vc4/vc4_drv.c
> @@ -298,6 +298,7 @@ static struct platform_driver *const component_drivers[] = {
>  	&vc4_hdmi_driver,
>  	&vc4_vec_driver,
>  	&vc4_dpi_driver,
> +	&vc4_dsi_driver,
>  	&vc4_hvs_driver,
>  	&vc4_crtc_driver,
>  	&vc4_v3d_driver,
> diff --git a/drivers/gpu/drm/vc4/vc4_drv.h b/drivers/gpu/drm/vc4/vc4_drv.h
> index b5c4bb14d0d1..723f0ec940ac 100644
> --- a/drivers/gpu/drm/vc4/vc4_drv.h
> +++ b/drivers/gpu/drm/vc4/vc4_drv.h
> @@ -17,6 +17,7 @@ struct vc4_dev {
>  	struct vc4_crtc *crtc[3];
>  	struct vc4_v3d *v3d;
>  	struct vc4_dpi *dpi;
> +	struct vc4_dsi *dsi1;
>  	struct vc4_vec *vec;
>  
>  	struct drm_fbdev_cma *fbdev;
> @@ -465,6 +466,10 @@ void __iomem *vc4_ioremap_regs(struct platform_device *dev, int index);
>  extern struct platform_driver vc4_dpi_driver;
>  int vc4_dpi_debugfs_regs(struct seq_file *m, void *unused);
>  
> +/* vc4_dsi.c */
> +extern struct platform_driver vc4_dsi_driver;
> +int vc4_dsi_debugfs_regs(struct seq_file *m, void *unused);
> +
>  /* vc4_gem.c */
>  void vc4_gem_init(struct drm_device *dev);
>  void vc4_gem_destroy(struct drm_device *dev);
> diff --git a/drivers/gpu/drm/vc4/vc4_dsi.c b/drivers/gpu/drm/vc4/vc4_dsi.c
> new file mode 100644
> index 000000000000..17fcac381dbb
> --- /dev/null
> +++ b/drivers/gpu/drm/vc4/vc4_dsi.c
> @@ -0,0 +1,1725 @@
> +/*
> + * Copyright (C) 2016 Broadcom
> + *
> + * This program is free software; you can redistribute it and/or modify it
> + * under the terms of the GNU General Public License version 2 as published by
> + * the Free Software Foundation.
> + *
> + * This program is distributed in the hope that it will be useful, but WITHOUT
> + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
> + * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
> + * more details.
> + *
> + * You should have received a copy of the GNU General Public License along with
> + * this program.  If not, see <http://www.gnu.org/licenses/>.
> + */
> +
> +/**
> + * DOC: VC4 DSI0/DSI1 module

Since you're bothering with kerneldoc, I strongly recommend you add a
vc4.rst in Documentation/gpu, include it together with the other drivers
(atm only i915, but Noralf will add one for tinydrm) and then add stanzas
to pull your kerneldoc in. That's the only way to lint it (at least for
now, until maybe we merge Jani's make target to lint all the kerneldocs),
and I think slowly building up driver docs would be really sweet.

Anyway, just an idea for the future.

> + *
> + * BCM2835 contains two DSI modules, DSI0 and DSI1.  DSI0 is a
> + * single-lane DSI controller, while DSI1 is a more modern 4-lane DSI
> + * controller.
> + *
> + * Most Raspberry Pi boards expose DSI1 as their "DISPLAY" connector,
> + * while the compute module brings both DSI0 and DSI1 out.
> + *
> + * This driver has been tested for DSI1 video-mode display only
> + * currently, with most of the information necessary for DSI0
> + * hopefully present.
> + */
> +
> +#include "drm_atomic_helper.h"
> +#include "drm_crtc_helper.h"
> +#include "drm_edid.h"
> +#include "drm_mipi_dsi.h"
> +#include "drm_panel.h"
> +#include "linux/clk.h"
> +#include "linux/clk-provider.h"
> +#include "linux/completion.h"
> +#include "linux/component.h"
> +#include "linux/dmaengine.h"
> +#include "linux/i2c.h"
> +#include "linux/of_address.h"
> +#include "linux/of_platform.h"
> +#include "linux/pm_runtime.h"
> +#include "vc4_drv.h"
> +#include "vc4_regs.h"
> +
> +#define DSI_CMD_FIFO_DEPTH  16
> +#define DSI_PIX_FIFO_DEPTH 256
> +#define DSI_PIX_FIFO_WIDTH   4
> +
> +#define DSI0_CTRL		0x00
> +
> +/* Command packet control. */
> +#define DSI0_TXPKT1C		0x04 /* AKA PKTC */
> +#define DSI1_TXPKT1C		0x04
> +# define DSI_TXPKT1C_TRIG_CMD_MASK	VC4_MASK(31, 24)
> +# define DSI_TXPKT1C_TRIG_CMD_SHIFT	24
> +# define DSI_TXPKT1C_CMD_REPEAT_MASK	VC4_MASK(23, 10)
> +# define DSI_TXPKT1C_CMD_REPEAT_SHIFT	10
> +
> +# define DSI_TXPKT1C_DISPLAY_NO_MASK	VC4_MASK(9, 8)
> +# define DSI_TXPKT1C_DISPLAY_NO_SHIFT	8
> +/* Short, trigger, BTA, or a long packet that fits all in CMDFIFO. */
> +# define DSI_TXPKT1C_DISPLAY_NO_SHORT		0
> +/* Primary display where cmdfifo provides part of the payload and
> + * pixelvalve the rest.
> + */
> +# define DSI_TXPKT1C_DISPLAY_NO_PRIMARY		1
> +/* Secondary display where cmdfifo provides part of the payload and
> + * pixfifo the rest.
> + */
> +# define DSI_TXPKT1C_DISPLAY_NO_SECONDARY	2
> +
> +# define DSI_TXPKT1C_CMD_TX_TIME_MASK	VC4_MASK(7, 6)
> +# define DSI_TXPKT1C_CMD_TX_TIME_SHIFT	6
> +
> +# define DSI_TXPKT1C_CMD_CTRL_MASK	VC4_MASK(5, 4)
> +# define DSI_TXPKT1C_CMD_CTRL_SHIFT	4
> +/* Command only.  Uses TXPKT1H and DISPLAY_NO */
> +# define DSI_TXPKT1C_CMD_CTRL_TX	0
> +/* Command with BTA for either ack or read data. */
> +# define DSI_TXPKT1C_CMD_CTRL_RX	1
> +/* Trigger according to TRIG_CMD */
> +# define DSI_TXPKT1C_CMD_CTRL_TRIG	2
> +/* BTA alone for getting error status after a command, or a TE trigger
> + * without a previous command.
> + */
> +# define DSI_TXPKT1C_CMD_CTRL_BTA	3
> +
> +# define DSI_TXPKT1C_CMD_MODE_LP	BIT(3)
> +# define DSI_TXPKT1C_CMD_TYPE_LONG	BIT(2)
> +# define DSI_TXPKT1C_CMD_TE_EN		BIT(1)
> +# define DSI_TXPKT1C_CMD_EN		BIT(0)
> +
> +/* Command packet header. */
> +#define DSI0_TXPKT1H		0x08 /* AKA PKTH */
> +#define DSI1_TXPKT1H		0x08
> +# define DSI_TXPKT1H_BC_CMDFIFO_MASK	VC4_MASK(31, 24)
> +# define DSI_TXPKT1H_BC_CMDFIFO_SHIFT	24
> +# define DSI_TXPKT1H_BC_PARAM_MASK	VC4_MASK(23, 8)
> +# define DSI_TXPKT1H_BC_PARAM_SHIFT	8
> +# define DSI_TXPKT1H_BC_DT_MASK		VC4_MASK(7, 0)
> +# define DSI_TXPKT1H_BC_DT_SHIFT	0
> +
> +#define DSI0_RXPKT1H		0x0c /* AKA RX1_PKTH */
> +#define DSI1_RXPKT1H		0x14
> +# define DSI_RXPKT1H_CRC_ERR		BIT(31)
> +# define DSI_RXPKT1H_DET_ERR		BIT(30)
> +# define DSI_RXPKT1H_ECC_ERR		BIT(29)
> +# define DSI_RXPKT1H_COR_ERR		BIT(28)
> +# define DSI_RXPKT1H_INCOMP_PKT		BIT(25)
> +# define DSI_RXPKT1H_PKT_TYPE_LONG	BIT(24)
> +/* Byte count if DSI_RXPKT1H_PKT_TYPE_LONG */
> +# define DSI_RXPKT1H_BC_PARAM_MASK	VC4_MASK(23, 8)
> +# define DSI_RXPKT1H_BC_PARAM_SHIFT	8
> +/* Short return bytes if !DSI_RXPKT1H_PKT_TYPE_LONG */
> +# define DSI_RXPKT1H_SHORT_1_MASK	VC4_MASK(23, 16)
> +# define DSI_RXPKT1H_SHORT_1_SHIFT	16
> +# define DSI_RXPKT1H_SHORT_0_MASK	VC4_MASK(15, 8)
> +# define DSI_RXPKT1H_SHORT_0_SHIFT	8
> +# define DSI_RXPKT1H_DT_LP_CMD_MASK	VC4_MASK(7, 0)
> +# define DSI_RXPKT1H_DT_LP_CMD_SHIFT	0
> +
> +#define DSI0_RXPKT2H		0x10 /* AKA RX2_PKTH */
> +#define DSI1_RXPKT2H		0x18
> +# define DSI_RXPKT1H_DET_ERR		BIT(30)
> +# define DSI_RXPKT1H_ECC_ERR		BIT(29)
> +# define DSI_RXPKT1H_COR_ERR		BIT(28)
> +# define DSI_RXPKT1H_INCOMP_PKT		BIT(25)
> +# define DSI_RXPKT1H_BC_PARAM_MASK	VC4_MASK(23, 8)
> +# define DSI_RXPKT1H_BC_PARAM_SHIFT	8
> +# define DSI_RXPKT1H_DT_MASK		VC4_MASK(7, 0)
> +# define DSI_RXPKT1H_DT_SHIFT		0
> +
> +#define DSI0_TXPKT_CMD_FIFO	0x14 /* AKA CMD_DATAF */
> +#define DSI1_TXPKT_CMD_FIFO	0x1c
> +
> +#define DSI0_DISP0_CTRL		0x18
> +# define DSI_DISP0_PIX_CLK_DIV_MASK	VC4_MASK(21, 13)
> +# define DSI_DISP0_PIX_CLK_DIV_SHIFT	13
> +# define DSI_DISP0_LP_STOP_CTRL_MASK	VC4_MASK(12, 11)
> +# define DSI_DISP0_LP_STOP_CTRL_SHIFT	11
> +# define DSI_DISP0_LP_STOP_DISABLE	0
> +# define DSI_DISP0_LP_STOP_PERLINE	1
> +# define DSI_DISP0_LP_STOP_PERFRAME	2
> +
> +/* Transmit RGB pixels and null packets only during HACTIVE, instead
> + * of going to LP-STOP.
> + */
> +# define DSI_DISP_HACTIVE_NULL		BIT(10)
> +/* Transmit blanking packet only during vblank, instead of allowing LP-STOP. */
> +# define DSI_DISP_VBLP_CTRL		BIT(9)
> +/* Transmit blanking packet only during HFP, instead of allowing LP-STOP. */
> +# define DSI_DISP_HFP_CTRL		BIT(8)
> +/* Transmit blanking packet only during HBP, instead of allowing LP-STOP. */
> +# define DSI_DISP_HBP_CTRL		BIT(7)
> +# define DSI_DISP0_CHANNEL_MASK		VC4_MASK(6, 5)
> +# define DSI_DISP0_CHANNEL_SHIFT	5
> +/* Enables end events for HSYNC/VSYNC, not just start events. */
> +# define DSI_DISP0_ST_END		BIT(4)
> +# define DSI_DISP0_PFORMAT_MASK		VC4_MASK(3, 2)
> +# define DSI_DISP0_PFORMAT_SHIFT	2
> +# define DSI_PFORMAT_RGB565		0
> +# define DSI_PFORMAT_RGB666_PACKED	1
> +# define DSI_PFORMAT_RGB666		2
> +# define DSI_PFORMAT_RGB888		3
> +/* Default is VIDEO mode. */
> +# define DSI_DISP0_COMMAND_MODE		BIT(1)
> +# define DSI_DISP0_ENABLE		BIT(0)
> +
> +#define DSI0_DISP1_CTRL		0x1c
> +#define DSI1_DISP1_CTRL		0x2c
> +/* Format of the data written to TXPKT_PIX_FIFO. */
> +# define DSI_DISP1_PFORMAT_MASK		VC4_MASK(2, 1)
> +# define DSI_DISP1_PFORMAT_SHIFT	1
> +# define DSI_DISP1_PFORMAT_16BIT	0
> +# define DSI_DISP1_PFORMAT_24BIT	1
> +# define DSI_DISP1_PFORMAT_32BIT_LE	2
> +# define DSI_DISP1_PFORMAT_32BIT_BE	3
> +
> +/* DISP1 is always command mode. */
> +# define DSI_DISP1_ENABLE		BIT(0)
> +
> +#define DSI0_TXPKT_PIX_FIFO		0x20 /* AKA PIX_FIFO */
> +
> +#define DSI0_INT_STAT		0x24
> +#define DSI0_INT_EN		0x28
> +# define DSI1_INT_PHY_D3_ULPS		BIT(30)
> +# define DSI1_INT_PHY_D3_STOP		BIT(29)
> +# define DSI1_INT_PHY_D2_ULPS		BIT(28)
> +# define DSI1_INT_PHY_D2_STOP		BIT(27)
> +# define DSI1_INT_PHY_D1_ULPS		BIT(26)
> +# define DSI1_INT_PHY_D1_STOP		BIT(25)
> +# define DSI1_INT_PHY_D0_ULPS		BIT(24)
> +# define DSI1_INT_PHY_D0_STOP		BIT(23)
> +# define DSI1_INT_FIFO_ERR		BIT(22)
> +# define DSI1_INT_PHY_DIR_RTF		BIT(21)
> +# define DSI1_INT_PHY_RXLPDT		BIT(20)
> +# define DSI1_INT_PHY_RXTRIG		BIT(19)
> +# define DSI1_INT_PHY_D0_LPDT		BIT(18)
> +# define DSI1_INT_PHY_DIR_FTR		BIT(17)
> +
> +/* Signaled when the clock lane enters the given state. */
> +# define DSI1_INT_PHY_CLOCK_ULPS	BIT(16)
> +# define DSI1_INT_PHY_CLOCK_HS		BIT(15)
> +# define DSI1_INT_PHY_CLOCK_STOP	BIT(14)
> +
> +/* Signaled on timeouts */
> +# define DSI1_INT_PR_TO			BIT(13)
> +# define DSI1_INT_TA_TO			BIT(12)
> +# define DSI1_INT_LPRX_TO		BIT(11)
> +# define DSI1_INT_HSTX_TO		BIT(10)
> +
> +/* Contention on a line when trying to drive the line low */
> +# define DSI1_INT_ERR_CONT_LP1		BIT(9)
> +# define DSI1_INT_ERR_CONT_LP0		BIT(8)
> +
> +/* Control error: incorrect line state sequence on data lane 0. */
> +# define DSI1_INT_ERR_CONTROL		BIT(7)
> +/* LPDT synchronization error (bits received not a multiple of 8. */
> +
> +# define DSI1_INT_ERR_SYNC_ESC		BIT(6)
> +/* Signaled after receiving an error packet from the display in
> + * response to a read.
> + */
> +# define DSI1_INT_RXPKT2		BIT(5)
> +/* Signaled after receiving a packet.  The header and optional short
> + * response will be in RXPKT1H, and a long response will be in the
> + * RXPKT_FIFO.
> + */
> +# define DSI1_INT_RXPKT1		BIT(4)
> +# define DSI1_INT_TXPKT2_DONE		BIT(3)
> +# define DSI1_INT_TXPKT2_END		BIT(2)
> +/* Signaled after all repeats of TXPKT1 are transferred. */
> +# define DSI1_INT_TXPKT1_DONE		BIT(1)
> +/* Signaled after each TXPKT1 repeat is scheduled. */
> +# define DSI1_INT_TXPKT1_END		BIT(0)
> +
> +#define DSI1_INTERRUPTS_ALWAYS_ENABLED	(DSI1_INT_ERR_SYNC_ESC | \
> +					 DSI1_INT_ERR_CONTROL |	 \
> +					 DSI1_INT_ERR_CONT_LP0 | \
> +					 DSI1_INT_ERR_CONT_LP1 | \
> +					 DSI1_INT_HSTX_TO |	 \
> +					 DSI1_INT_LPRX_TO |	 \
> +					 DSI1_INT_TA_TO |	 \
> +					 DSI1_INT_PR_TO)
> +
> +#define DSI0_STAT		0x2c
> +#define DSI0_HSTX_TO_CNT	0x30
> +#define DSI0_LPRX_TO_CNT	0x34
> +#define DSI0_TA_TO_CNT		0x38
> +#define DSI0_PR_TO_CNT		0x3c
> +#define DSI0_PHYC		0x40
> +# define DSI1_PHYC_ESC_CLK_LPDT_MASK	VC4_MASK(25, 20)
> +# define DSI1_PHYC_ESC_CLK_LPDT_SHIFT	20
> +# define DSI1_PHYC_HS_CLK_CONTINUOUS	BIT(18)
> +# define DSI0_PHYC_ESC_CLK_LPDT_MASK	VC4_MASK(17, 12)
> +# define DSI0_PHYC_ESC_CLK_LPDT_SHIFT	12
> +# define DSI1_PHYC_CLANE_ULPS		BIT(17)
> +# define DSI1_PHYC_CLANE_ENABLE		BIT(16)
> +# define DSI_PHYC_DLANE3_ULPS		BIT(13)
> +# define DSI_PHYC_DLANE3_ENABLE		BIT(12)
> +# define DSI0_PHYC_HS_CLK_CONTINUOUS	BIT(10)
> +# define DSI0_PHYC_CLANE_ULPS		BIT(9)
> +# define DSI_PHYC_DLANE2_ULPS		BIT(9)
> +# define DSI0_PHYC_CLANE_ENABLE		BIT(8)
> +# define DSI_PHYC_DLANE2_ENABLE		BIT(8)
> +# define DSI_PHYC_DLANE1_ULPS		BIT(5)
> +# define DSI_PHYC_DLANE1_ENABLE		BIT(4)
> +# define DSI_PHYC_DLANE0_FORCE_STOP	BIT(2)
> +# define DSI_PHYC_DLANE0_ULPS		BIT(1)
> +# define DSI_PHYC_DLANE0_ENABLE		BIT(0)
> +
> +#define DSI0_HS_CLT0		0x44
> +#define DSI0_HS_CLT1		0x48
> +#define DSI0_HS_CLT2		0x4c
> +#define DSI0_HS_DLT3		0x50
> +#define DSI0_HS_DLT4		0x54
> +#define DSI0_HS_DLT5		0x58
> +#define DSI0_HS_DLT6		0x5c
> +#define DSI0_HS_DLT7		0x60
> +
> +#define DSI0_PHY_AFEC0		0x64
> +# define DSI0_PHY_AFEC0_DDR2CLK_EN		BIT(26)
> +# define DSI0_PHY_AFEC0_DDRCLK_EN		BIT(25)
> +# define DSI0_PHY_AFEC0_LATCH_ULPS		BIT(24)
> +# define DSI1_PHY_AFEC0_IDR_DLANE3_MASK		VC4_MASK(31, 29)
> +# define DSI1_PHY_AFEC0_IDR_DLANE3_SHIFT	29
> +# define DSI1_PHY_AFEC0_IDR_DLANE2_MASK		VC4_MASK(28, 26)
> +# define DSI1_PHY_AFEC0_IDR_DLANE2_SHIFT	26
> +# define DSI1_PHY_AFEC0_IDR_DLANE1_MASK		VC4_MASK(27, 23)
> +# define DSI1_PHY_AFEC0_IDR_DLANE1_SHIFT	23
> +# define DSI1_PHY_AFEC0_IDR_DLANE0_MASK		VC4_MASK(22, 20)
> +# define DSI1_PHY_AFEC0_IDR_DLANE0_SHIFT	20
> +# define DSI1_PHY_AFEC0_IDR_CLANE_MASK		VC4_MASK(19, 17)
> +# define DSI1_PHY_AFEC0_IDR_CLANE_SHIFT		17
> +# define DSI0_PHY_AFEC0_ACTRL_DLANE1_MASK	VC4_MASK(23, 20)
> +# define DSI0_PHY_AFEC0_ACTRL_DLANE1_SHIFT	20
> +# define DSI0_PHY_AFEC0_ACTRL_DLANE0_MASK	VC4_MASK(19, 16)
> +# define DSI0_PHY_AFEC0_ACTRL_DLANE0_SHIFT	16
> +# define DSI0_PHY_AFEC0_ACTRL_CLANE_MASK	VC4_MASK(15, 12)
> +# define DSI0_PHY_AFEC0_ACTRL_CLANE_SHIFT	12
> +# define DSI1_PHY_AFEC0_DDR2CLK_EN		BIT(16)
> +# define DSI1_PHY_AFEC0_DDRCLK_EN		BIT(15)
> +# define DSI1_PHY_AFEC0_LATCH_ULPS		BIT(14)
> +# define DSI1_PHY_AFEC0_RESET			BIT(13)
> +# define DSI1_PHY_AFEC0_PD			BIT(12)
> +# define DSI0_PHY_AFEC0_RESET			BIT(11)
> +# define DSI1_PHY_AFEC0_PD_BG			BIT(11)
> +# define DSI0_PHY_AFEC0_PD			BIT(10)
> +# define DSI1_PHY_AFEC0_PD_DLANE3		BIT(10)
> +# define DSI0_PHY_AFEC0_PD_BG			BIT(9)
> +# define DSI1_PHY_AFEC0_PD_DLANE2		BIT(9)
> +# define DSI0_PHY_AFEC0_PD_DLANE1		BIT(8)
> +# define DSI1_PHY_AFEC0_PD_DLANE1		BIT(8)
> +# define DSI_PHY_AFEC0_PTATADJ_MASK		VC4_MASK(7, 4)
> +# define DSI_PHY_AFEC0_PTATADJ_SHIFT		4
> +# define DSI_PHY_AFEC0_CTATADJ_MASK		VC4_MASK(3, 0)
> +# define DSI_PHY_AFEC0_CTATADJ_SHIFT		0
> +
> +#define DSI0_PHY_AFEC1		0x68
> +# define DSI0_PHY_AFEC1_IDR_DLANE1_MASK		VC4_MASK(10, 8)
> +# define DSI0_PHY_AFEC1_IDR_DLANE1_SHIFT	8
> +# define DSI0_PHY_AFEC1_IDR_DLANE0_MASK		VC4_MASK(6, 4)
> +# define DSI0_PHY_AFEC1_IDR_DLANE0_SHIFT	4
> +# define DSI0_PHY_AFEC1_IDR_CLANE_MASK		VC4_MASK(2, 0)
> +# define DSI0_PHY_AFEC1_IDR_CLANE_SHIFT		0
> +
> +#define DSI0_TST_SEL		0x6c
> +#define DSI0_TST_MON		0x70
> +#define DSI0_ID			0x74
> +# define DSI_ID_VALUE		0x00647369
> +
> +#define DSI1_CTRL		0x00
> +# define DSI_CTRL_HS_CLKC_MASK		VC4_MASK(15, 14)
> +# define DSI_CTRL_HS_CLKC_SHIFT		14
> +# define DSI_CTRL_HS_CLKC_BYTE		0
> +# define DSI_CTRL_HS_CLKC_DDR2		1
> +# define DSI_CTRL_HS_CLKC_DDR		2
> +
> +# define DSI_CTRL_RX_LPDT_EOT_DISABLE	BIT(13)
> +# define DSI_CTRL_LPDT_EOT_DISABLE	BIT(12)
> +# define DSI_CTRL_HSDT_EOT_DISABLE	BIT(11)
> +# define DSI_CTRL_SOFT_RESET_CFG	BIT(10)
> +# define DSI_CTRL_CAL_BYTE		BIT(9)
> +# define DSI_CTRL_INV_BYTE		BIT(8)
> +# define DSI_CTRL_CLR_LDF		BIT(7)
> +# define DSI0_CTRL_CLR_PBCF		BIT(6)
> +# define DSI1_CTRL_CLR_RXF		BIT(6)
> +# define DSI0_CTRL_CLR_CPBCF		BIT(5)
> +# define DSI1_CTRL_CLR_PDF		BIT(5)
> +# define DSI0_CTRL_CLR_PDF		BIT(4)
> +# define DSI1_CTRL_CLR_CDF		BIT(4)
> +# define DSI0_CTRL_CLR_CDF		BIT(3)
> +# define DSI0_CTRL_CTRL2		BIT(2)
> +# define DSI1_CTRL_DISABLE_DISP_CRCC	BIT(2)
> +# define DSI0_CTRL_CTRL1		BIT(1)
> +# define DSI1_CTRL_DISABLE_DISP_ECCC	BIT(1)
> +# define DSI0_CTRL_CTRL0		BIT(0)
> +# define DSI1_CTRL_EN			BIT(0)
> +# define DSI0_CTRL_RESET_FIFOS		(DSI_CTRL_CLR_LDF | \
> +					 DSI0_CTRL_CLR_PBCF | \
> +					 DSI0_CTRL_CLR_CPBCF |	\
> +					 DSI0_CTRL_CLR_PDF | \
> +					 DSI0_CTRL_CLR_CDF)
> +# define DSI1_CTRL_RESET_FIFOS		(DSI_CTRL_CLR_LDF | \
> +					 DSI1_CTRL_CLR_RXF | \
> +					 DSI1_CTRL_CLR_PDF | \
> +					 DSI1_CTRL_CLR_CDF)
> +
> +#define DSI1_TXPKT2C		0x0c
> +#define DSI1_TXPKT2H		0x10
> +#define DSI1_TXPKT_PIX_FIFO	0x20
> +#define DSI1_RXPKT_FIFO		0x24
> +#define DSI1_DISP0_CTRL		0x28
> +#define DSI1_INT_STAT		0x30
> +#define DSI1_INT_EN		0x34
> +/* State reporting bits.  These mostly behave like INT_STAT, where
> + * writing a 1 clears the bit.
> + */
> +#define DSI1_STAT		0x38
> +# define DSI1_STAT_PHY_D3_ULPS		BIT(31)
> +# define DSI1_STAT_PHY_D3_STOP		BIT(30)
> +# define DSI1_STAT_PHY_D2_ULPS		BIT(29)
> +# define DSI1_STAT_PHY_D2_STOP		BIT(28)
> +# define DSI1_STAT_PHY_D1_ULPS		BIT(27)
> +# define DSI1_STAT_PHY_D1_STOP		BIT(26)
> +# define DSI1_STAT_PHY_D0_ULPS		BIT(25)
> +# define DSI1_STAT_PHY_D0_STOP		BIT(24)
> +# define DSI1_STAT_FIFO_ERR		BIT(23)
> +# define DSI1_STAT_PHY_RXLPDT		BIT(22)
> +# define DSI1_STAT_PHY_RXTRIG		BIT(21)
> +# define DSI1_STAT_PHY_D0_LPDT		BIT(20)
> +/* Set when in forward direction */
> +# define DSI1_STAT_PHY_DIR		BIT(19)
> +# define DSI1_STAT_PHY_CLOCK_ULPS	BIT(18)
> +# define DSI1_STAT_PHY_CLOCK_HS		BIT(17)
> +# define DSI1_STAT_PHY_CLOCK_STOP	BIT(16)
> +# define DSI1_STAT_PR_TO		BIT(15)
> +# define DSI1_STAT_TA_TO		BIT(14)
> +# define DSI1_STAT_LPRX_TO		BIT(13)
> +# define DSI1_STAT_HSTX_TO		BIT(12)
> +# define DSI1_STAT_ERR_CONT_LP1		BIT(11)
> +# define DSI1_STAT_ERR_CONT_LP0		BIT(10)
> +# define DSI1_STAT_ERR_CONTROL		BIT(9)
> +# define DSI1_STAT_ERR_SYNC_ESC		BIT(8)
> +# define DSI1_STAT_RXPKT2		BIT(7)
> +# define DSI1_STAT_RXPKT1		BIT(6)
> +# define DSI1_STAT_TXPKT2_BUSY		BIT(5)
> +# define DSI1_STAT_TXPKT2_DONE		BIT(4)
> +# define DSI1_STAT_TXPKT2_END		BIT(3)
> +# define DSI1_STAT_TXPKT1_BUSY		BIT(2)
> +# define DSI1_STAT_TXPKT1_DONE		BIT(1)
> +# define DSI1_STAT_TXPKT1_END		BIT(0)
> +
> +#define DSI1_HSTX_TO_CNT	0x3c
> +#define DSI1_LPRX_TO_CNT	0x40
> +#define DSI1_TA_TO_CNT		0x44
> +#define DSI1_PR_TO_CNT		0x48
> +#define DSI1_PHYC		0x4c
> +
> +#define DSI1_HS_CLT0		0x50
> +# define DSI_HS_CLT0_CZERO_MASK		VC4_MASK(26, 18)
> +# define DSI_HS_CLT0_CZERO_SHIFT	18
> +# define DSI_HS_CLT0_CPRE_MASK		VC4_MASK(17, 9)
> +# define DSI_HS_CLT0_CPRE_SHIFT		9
> +# define DSI_HS_CLT0_CPREP_MASK		VC4_MASK(8, 0)
> +# define DSI_HS_CLT0_CPREP_SHIFT	0
> +
> +#define DSI1_HS_CLT1		0x54
> +# define DSI_HS_CLT1_CTRAIL_MASK	VC4_MASK(17, 9)
> +# define DSI_HS_CLT1_CTRAIL_SHIFT	9
> +# define DSI_HS_CLT1_CPOST_MASK		VC4_MASK(8, 0)
> +# define DSI_HS_CLT1_CPOST_SHIFT	0
> +
> +#define DSI1_HS_CLT2		0x58
> +# define DSI_HS_CLT2_WUP_MASK		VC4_MASK(23, 0)
> +# define DSI_HS_CLT2_WUP_SHIFT		0
> +
> +#define DSI1_HS_DLT3		0x5c
> +# define DSI_HS_DLT3_EXIT_MASK		VC4_MASK(26, 18)
> +# define DSI_HS_DLT3_EXIT_SHIFT		18
> +# define DSI_HS_DLT3_ZERO_MASK		VC4_MASK(17, 9)
> +# define DSI_HS_DLT3_ZERO_SHIFT		9
> +# define DSI_HS_DLT3_PRE_MASK		VC4_MASK(8, 0)
> +# define DSI_HS_DLT3_PRE_SHIFT		0
> +
> +#define DSI1_HS_DLT4		0x60
> +# define DSI_HS_DLT4_ANLAT_MASK		VC4_MASK(22, 18)
> +# define DSI_HS_DLT4_ANLAT_SHIFT	18
> +# define DSI_HS_DLT4_TRAIL_MASK		VC4_MASK(17, 9)
> +# define DSI_HS_DLT4_TRAIL_SHIFT	9
> +# define DSI_HS_DLT4_LPX_MASK		VC4_MASK(8, 0)
> +# define DSI_HS_DLT4_LPX_SHIFT		0
> +
> +#define DSI1_HS_DLT5		0x64
> +# define DSI_HS_DLT5_INIT_MASK		VC4_MASK(23, 0)
> +# define DSI_HS_DLT5_INIT_SHIFT		0
> +
> +#define DSI1_HS_DLT6		0x68
> +# define DSI_HS_DLT6_TA_GET_MASK	VC4_MASK(31, 24)
> +# define DSI_HS_DLT6_TA_GET_SHIFT	24
> +# define DSI_HS_DLT6_TA_SURE_MASK	VC4_MASK(23, 16)
> +# define DSI_HS_DLT6_TA_SURE_SHIFT	16
> +# define DSI_HS_DLT6_TA_GO_MASK		VC4_MASK(15, 8)
> +# define DSI_HS_DLT6_TA_GO_SHIFT	8
> +# define DSI_HS_DLT6_LP_LPX_MASK	VC4_MASK(7, 0)
> +# define DSI_HS_DLT6_LP_LPX_SHIFT	0
> +
> +#define DSI1_HS_DLT7		0x6c
> +# define DSI_HS_DLT7_LP_WUP_MASK	VC4_MASK(23, 0)
> +# define DSI_HS_DLT7_LP_WUP_SHIFT	0
> +
> +#define DSI1_PHY_AFEC0		0x70
> +
> +#define DSI1_PHY_AFEC1		0x74
> +# define DSI1_PHY_AFEC1_ACTRL_DLANE3_MASK	VC4_MASK(19, 16)
> +# define DSI1_PHY_AFEC1_ACTRL_DLANE3_SHIFT	16
> +# define DSI1_PHY_AFEC1_ACTRL_DLANE2_MASK	VC4_MASK(15, 12)
> +# define DSI1_PHY_AFEC1_ACTRL_DLANE2_SHIFT	12
> +# define DSI1_PHY_AFEC1_ACTRL_DLANE1_MASK	VC4_MASK(11, 8)
> +# define DSI1_PHY_AFEC1_ACTRL_DLANE1_SHIFT	8
> +# define DSI1_PHY_AFEC1_ACTRL_DLANE0_MASK	VC4_MASK(7, 4)
> +# define DSI1_PHY_AFEC1_ACTRL_DLANE0_SHIFT	4
> +# define DSI1_PHY_AFEC1_ACTRL_CLANE_MASK	VC4_MASK(3, 0)
> +# define DSI1_PHY_AFEC1_ACTRL_CLANE_SHIFT	0
> +
> +#define DSI1_TST_SEL		0x78
> +#define DSI1_TST_MON		0x7c
> +#define DSI1_PHY_TST1		0x80
> +#define DSI1_PHY_TST2		0x84
> +#define DSI1_PHY_FIFO_STAT	0x88
> +/* Actually, all registers in the range that aren't otherwise claimed
> + * will return the ID.
> + */
> +#define DSI1_ID			0x8c
> +
> +/* General DSI hardware state. */
> +struct vc4_dsi {
> +	struct platform_device *pdev;
> +
> +	struct mipi_dsi_host dsi_host;
> +	struct drm_encoder *encoder;
> +	struct drm_connector *connector;
> +	struct drm_panel *panel;
> +
> +	void __iomem *regs;
> +
> +	struct dma_chan *reg_dma_chan;
> +	dma_addr_t reg_dma_paddr;
> +	u32 *reg_dma_mem;
> +	dma_addr_t reg_paddr;
> +
> +	/* Whether we're on bcm2835's DSI0 or DSI1. */
> +	int port;
> +
> +	/* DSI channel for the panel we're connected to. */
> +	u32 channel;
> +	u32 lanes;
> +	enum mipi_dsi_pixel_format format;
> +	u32 mode_flags;
> +
> +	/* Input clock from CPRMAN to the digital PHY, for the DSI
> +	 * escape clock.
> +	 */
> +	struct clk *escape_clock;
> +
> +	/* Input clock to the analog PHY, used to generate the DSI bit
> +	 * clock.
> +	 */
> +	struct clk *pll_phy_clock;
> +
> +	/* HS Clocks generated within the DSI analog PHY. */
> +	struct clk_fixed_factor phy_clocks[3];
> +
> +	struct clk_onecell_data clk_onecell;
> +
> +	/* Pixel clock output to the pixelvalve, generated from the HS
> +	 * clock.
> +	 */
> +	struct clk *pixel_clock;
> +
> +	struct completion xfer_completion;
> +	int xfer_result;
> +};
> +
> +#define host_to_dsi(host) container_of(host, struct vc4_dsi, dsi_host)
> +
> +static inline void
> +dsi_dma_workaround_write(struct vc4_dsi *dsi, u32 offset, u32 val)
> +{
> +	struct dma_chan *chan = dsi->reg_dma_chan;
> +	struct dma_async_tx_descriptor *tx;
> +	dma_cookie_t cookie;
> +	int ret;
> +
> +	/* DSI0 should be able to write normally. */
> +	if (!chan) {
> +		writel(val, dsi->regs + offset);
> +		return;
> +	}
> +
> +	*dsi->reg_dma_mem = val;
> +
> +	tx = chan->device->device_prep_dma_memcpy(chan,
> +						  dsi->reg_paddr + offset,
> +						  dsi->reg_dma_paddr,
> +						  4, 0);
> +	if (!tx) {
> +		DRM_ERROR("Failed to set up DMA register write\n");
> +		return;
> +	}
> +
> +	cookie = tx->tx_submit(tx);
> +	ret = dma_submit_error(cookie);
> +	if (ret) {
> +		DRM_ERROR("Failed to submit DMA: %d\n", ret);
> +		return;
> +	}
> +	ret = dma_sync_wait(chan, cookie);
> +	if (ret)
> +		DRM_ERROR("Failed to wait for DMA: %d\n", ret);
> +}
> +
> +#define DSI_READ(offset) readl(dsi->regs + (offset))
> +#define DSI_WRITE(offset, val) dsi_dma_workaround_write(dsi, offset, val)
> +#define DSI_PORT_READ(offset) \
> +	DSI_READ(dsi->port ? DSI1_##offset : DSI0_##offset)
> +#define DSI_PORT_WRITE(offset, val) \
> +	DSI_WRITE(dsi->port ? DSI1_##offset : DSI0_##offset, val)
> +#define DSI_PORT_BIT(bit) (dsi->port ? DSI1_##bit : DSI0_##bit)
> +
> +/* VC4 DSI encoder KMS struct */
> +struct vc4_dsi_encoder {
> +	struct vc4_encoder base;
> +	struct vc4_dsi *dsi;
> +};
> +
> +static inline struct vc4_dsi_encoder *
> +to_vc4_dsi_encoder(struct drm_encoder *encoder)
> +{
> +	return container_of(encoder, struct vc4_dsi_encoder, base.base);
> +}
> +
> +/* VC4 DSI connector KMS struct */
> +struct vc4_dsi_connector {
> +	struct drm_connector base;
> +	struct vc4_dsi *dsi;
> +};
> +
> +static inline struct vc4_dsi_connector *
> +to_vc4_dsi_connector(struct drm_connector *connector)
> +{
> +	return container_of(connector, struct vc4_dsi_connector, base);
> +}
> +
> +#define DSI_REG(reg) { reg, #reg }
> +static const struct {
> +	u32 reg;
> +	const char *name;
> +} dsi0_regs[] = {
> +	DSI_REG(DSI0_CTRL),
> +	DSI_REG(DSI0_STAT),
> +	DSI_REG(DSI0_HSTX_TO_CNT),
> +	DSI_REG(DSI0_LPRX_TO_CNT),
> +	DSI_REG(DSI0_TA_TO_CNT),
> +	DSI_REG(DSI0_PR_TO_CNT),
> +	DSI_REG(DSI0_DISP0_CTRL),
> +	DSI_REG(DSI0_DISP1_CTRL),
> +	DSI_REG(DSI0_INT_STAT),
> +	DSI_REG(DSI0_INT_EN),
> +	DSI_REG(DSI0_PHYC),
> +	DSI_REG(DSI0_HS_CLT0),
> +	DSI_REG(DSI0_HS_CLT1),
> +	DSI_REG(DSI0_HS_CLT2),
> +	DSI_REG(DSI0_HS_DLT3),
> +	DSI_REG(DSI0_HS_DLT4),
> +	DSI_REG(DSI0_HS_DLT5),
> +	DSI_REG(DSI0_HS_DLT6),
> +	DSI_REG(DSI0_HS_DLT7),
> +	DSI_REG(DSI0_PHY_AFEC0),
> +	DSI_REG(DSI0_PHY_AFEC1),
> +	DSI_REG(DSI0_ID),
> +};
> +
> +static const struct {
> +	u32 reg;
> +	const char *name;
> +} dsi1_regs[] = {
> +	DSI_REG(DSI1_CTRL),
> +	DSI_REG(DSI1_STAT),
> +	DSI_REG(DSI1_HSTX_TO_CNT),
> +	DSI_REG(DSI1_LPRX_TO_CNT),
> +	DSI_REG(DSI1_TA_TO_CNT),
> +	DSI_REG(DSI1_PR_TO_CNT),
> +	DSI_REG(DSI1_DISP0_CTRL),
> +	DSI_REG(DSI1_DISP1_CTRL),
> +	DSI_REG(DSI1_INT_STAT),
> +	DSI_REG(DSI1_INT_EN),
> +	DSI_REG(DSI1_PHYC),
> +	DSI_REG(DSI1_HS_CLT0),
> +	DSI_REG(DSI1_HS_CLT1),
> +	DSI_REG(DSI1_HS_CLT2),
> +	DSI_REG(DSI1_HS_DLT3),
> +	DSI_REG(DSI1_HS_DLT4),
> +	DSI_REG(DSI1_HS_DLT5),
> +	DSI_REG(DSI1_HS_DLT6),
> +	DSI_REG(DSI1_HS_DLT7),
> +	DSI_REG(DSI1_PHY_AFEC0),
> +	DSI_REG(DSI1_PHY_AFEC1),
> +	DSI_REG(DSI1_ID),
> +};
> +
> +static void vc4_dsi_dump_regs(struct vc4_dsi *dsi)
> +{
> +	int i;
> +
> +	if (dsi->port == 0) {
> +		for (i = 0; i < ARRAY_SIZE(dsi0_regs); i++) {
> +			DRM_INFO("0x%04x (%s): 0x%08x\n",
> +				 dsi0_regs[i].reg, dsi0_regs[i].name,
> +				 DSI_READ(dsi0_regs[i].reg));
> +		}
> +	} else {
> +		for (i = 0; i < ARRAY_SIZE(dsi1_regs); i++) {
> +			DRM_INFO("0x%04x (%s): 0x%08x\n",
> +				 dsi1_regs[i].reg, dsi1_regs[i].name,
> +				 DSI_READ(dsi1_regs[i].reg));
> +		}
> +	}
> +}
> +
> +#ifdef CONFIG_DEBUG_FS
> +int vc4_dsi_debugfs_regs(struct seq_file *m, void *unused)
> +{
> +	struct drm_info_node *node = (struct drm_info_node *)m->private;
> +	struct drm_device *drm = node->minor->dev;
> +	struct vc4_dev *vc4 = to_vc4_dev(drm);
> +	int dsi_index = (uintptr_t)node->info_ent->data;
> +	struct vc4_dsi *dsi = (dsi_index == 1 ? vc4->dsi1 : NULL);
> +	int i;
> +
> +	if (!dsi)
> +		return 0;
> +
> +	if (dsi->port == 0) {
> +		for (i = 0; i < ARRAY_SIZE(dsi0_regs); i++) {
> +			seq_printf(m, "0x%04x (%s): 0x%08x\n",
> +				   dsi0_regs[i].reg, dsi0_regs[i].name,
> +				   DSI_READ(dsi0_regs[i].reg));
> +		}
> +	} else {
> +		for (i = 0; i < ARRAY_SIZE(dsi1_regs); i++) {
> +			seq_printf(m, "0x%04x (%s): 0x%08x\n",
> +				   dsi1_regs[i].reg, dsi1_regs[i].name,
> +				   DSI_READ(dsi1_regs[i].reg));
> +		}
> +	}
> +
> +	return 0;
> +}
> +#endif
> +
> +static enum drm_connector_status
> +vc4_dsi_connector_detect(struct drm_connector *connector, bool force)
> +{
> +	struct vc4_dsi_connector *vc4_connector =
> +		to_vc4_dsi_connector(connector);
> +	struct vc4_dsi *dsi = vc4_connector->dsi;
> +
> +	if (dsi->panel)
> +		return connector_status_connected;
> +	else
> +		return connector_status_disconnected;
> +}
> +
> +static void vc4_dsi_connector_destroy(struct drm_connector *connector)
> +{
> +	drm_connector_unregister(connector);
> +	drm_connector_cleanup(connector);
> +}
> +
> +static int vc4_dsi_connector_get_modes(struct drm_connector *connector)
> +{
> +	struct vc4_dsi_connector *vc4_connector =
> +		to_vc4_dsi_connector(connector);
> +	struct vc4_dsi *dsi = vc4_connector->dsi;
> +
> +	if (dsi->panel)
> +		return drm_panel_get_modes(dsi->panel);
> +
> +	return 0;
> +}

I'm still hoping that somewhen someone adds a drm_panel * pointer to
drm_connector and writes the glue functions in a helper library so we
could garbage-collect all our copies of the same stuff implementing
->detect and ->get_modes ...

> +
> +static const struct drm_connector_funcs vc4_dsi_connector_funcs = {
> +	.dpms = drm_atomic_helper_connector_dpms,
> +	.detect = vc4_dsi_connector_detect,
> +	.fill_modes = drm_helper_probe_single_connector_modes,
> +	.destroy = vc4_dsi_connector_destroy,
> +	.reset = drm_atomic_helper_connector_reset,
> +	.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
> +	.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
> +};
> +
> +static const struct drm_connector_helper_funcs vc4_dsi_connector_helper_funcs = {
> +	.get_modes = vc4_dsi_connector_get_modes,
> +};
> +
> +static struct drm_connector *vc4_dsi_connector_init(struct drm_device *dev,
> +						    struct vc4_dsi *dsi)
> +{
> +	struct drm_connector *connector = NULL;
> +	struct vc4_dsi_connector *dsi_connector;
> +	int ret = 0;
> +
> +	dsi_connector = devm_kzalloc(dev->dev, sizeof(*dsi_connector),
> +				     GFP_KERNEL);
> +	if (!dsi_connector) {
> +		ret = -ENOMEM;
> +		goto fail;
> +	}
> +	connector = &dsi_connector->base;
> +
> +	dsi_connector->dsi = dsi;
> +
> +	drm_connector_init(dev, connector, &vc4_dsi_connector_funcs,
> +			   DRM_MODE_CONNECTOR_DSI);
> +	drm_connector_helper_add(connector, &vc4_dsi_connector_helper_funcs);
> +
> +	connector->polled = 0;
> +	connector->interlace_allowed = 0;
> +	connector->doublescan_allowed = 0;
> +
> +	drm_mode_connector_attach_encoder(connector, dsi->encoder);
> +
> +	return connector;
> +
> +fail:
> +	if (connector)
> +		vc4_dsi_connector_destroy(connector);
> +
> +	return ERR_PTR(ret);
> +}
> +
> +static void vc4_dsi_encoder_destroy(struct drm_encoder *encoder)
> +{
> +	drm_encoder_cleanup(encoder);
> +}
> +
> +static const struct drm_encoder_funcs vc4_dsi_encoder_funcs = {
> +	.destroy = vc4_dsi_encoder_destroy,
> +};
> +
> +static void vc4_dsi_latch_ulps(struct vc4_dsi *dsi, bool latch)
> +{
> +	u32 afec0 = DSI_PORT_READ(PHY_AFEC0);
> +
> +	if (latch)
> +		afec0 |= DSI_PORT_BIT(PHY_AFEC0_LATCH_ULPS);
> +	else
> +		afec0 &= ~DSI_PORT_BIT(PHY_AFEC0_LATCH_ULPS);
> +
> +	DSI_PORT_WRITE(PHY_AFEC0, afec0);
> +}
> +
> +/* Enters or exits Ultra Low Power State. */
> +static void vc4_dsi_ulps(struct vc4_dsi *dsi, bool ulps)
> +{
> +	bool continuous = dsi->mode_flags & MIPI_DSI_CLOCK_NON_CONTINUOUS;
> +	u32 phyc_ulps = ((continuous ? DSI_PORT_BIT(PHYC_CLANE_ULPS) : 0) |
> +			 DSI_PHYC_DLANE0_ULPS |
> +			 (dsi->lanes > 1 ? DSI_PHYC_DLANE1_ULPS : 0) |
> +			 (dsi->lanes > 2 ? DSI_PHYC_DLANE2_ULPS : 0) |
> +			 (dsi->lanes > 3 ? DSI_PHYC_DLANE3_ULPS : 0));
> +	u32 stat_ulps = ((continuous ? DSI1_STAT_PHY_CLOCK_ULPS : 0) |
> +			 DSI1_STAT_PHY_D0_ULPS |
> +			 (dsi->lanes > 1 ? DSI1_STAT_PHY_D1_ULPS : 0) |
> +			 (dsi->lanes > 2 ? DSI1_STAT_PHY_D2_ULPS : 0) |
> +			 (dsi->lanes > 3 ? DSI1_STAT_PHY_D3_ULPS : 0));
> +	u32 stat_stop = ((continuous ? DSI1_STAT_PHY_CLOCK_STOP : 0) |
> +			 DSI1_STAT_PHY_D0_STOP |
> +			 (dsi->lanes > 1 ? DSI1_STAT_PHY_D1_STOP : 0) |
> +			 (dsi->lanes > 2 ? DSI1_STAT_PHY_D2_STOP : 0) |
> +			 (dsi->lanes > 3 ? DSI1_STAT_PHY_D3_STOP : 0));
> +	int ret;
> +
> +	DSI_PORT_WRITE(STAT, stat_ulps);
> +	DSI_PORT_WRITE(PHYC, DSI_PORT_READ(PHYC) | phyc_ulps);
> +	ret = wait_for((DSI_PORT_READ(STAT) & stat_ulps) == stat_ulps, 200);
> +	if (ret) {
> +		dev_warn(&dsi->pdev->dev,
> +			 "Timeout waiting for DSI ULPS entry: STAT 0x%08x",
> +			 DSI_PORT_READ(STAT));
> +		DSI_PORT_WRITE(PHYC, DSI_PORT_READ(PHYC) & ~phyc_ulps);
> +		vc4_dsi_latch_ulps(dsi, false);
> +		return;
> +	}
> +
> +	/* The DSI module can't be disabled while the module is
> +	 * generating ULPS state.  So, to be able to disable the
> +	 * module, we have the AFE latch the ULPS state and continue
> +	 * on to having the module enter STOP.
> +	 */
> +	vc4_dsi_latch_ulps(dsi, ulps);
> +
> +	DSI_PORT_WRITE(STAT, stat_stop);
> +	DSI_PORT_WRITE(PHYC, DSI_PORT_READ(PHYC) & ~phyc_ulps);
> +	ret = wait_for((DSI_PORT_READ(STAT) & stat_stop) == stat_stop, 200);
> +	if (ret) {
> +		dev_warn(&dsi->pdev->dev,
> +			 "Timeout waiting for DSI STOP entry: STAT 0x%08x",
> +			 DSI_PORT_READ(STAT));
> +		DSI_PORT_WRITE(PHYC, DSI_PORT_READ(PHYC) & ~phyc_ulps);
> +		return;
> +	}
> +}
> +
> +static u32
> +dsi_hs_timing(u32 ui_ns, u32 ns, u32 ui)
> +{
> +	/* The HS timings have to be rounded up to a multiple of 8
> +	 * because we're using the byte clock.
> +	 */
> +	return roundup(ui + DIV_ROUND_UP(ns, ui_ns), 8);
> +}
> +
> +/* ESC always runs at 100Mhz. */
> +#define ESC_TIME_NS 10
> +
> +static u32
> +dsi_esc_timing(u32 ns)
> +{
> +	return DIV_ROUND_UP(ns, ESC_TIME_NS);
> +}
> +
> +static void vc4_dsi_encoder_disable(struct drm_encoder *encoder)
> +{
> +	struct vc4_dsi_encoder *vc4_encoder = to_vc4_dsi_encoder(encoder);
> +	struct vc4_dsi *dsi = vc4_encoder->dsi;
> +	struct device *dev = &dsi->pdev->dev;
> +
> +	drm_panel_disable(dsi->panel);
> +
> +	vc4_dsi_ulps(dsi, true);
> +
> +	drm_panel_unprepare(dsi->panel);
> +
> +	clk_disable_unprepare(dsi->pll_phy_clock);
> +	clk_disable_unprepare(dsi->escape_clock);
> +	clk_disable_unprepare(dsi->pixel_clock);
> +
> +	pm_runtime_put(dev);
> +}
> +
> +static void vc4_dsi_encoder_enable(struct drm_encoder *encoder)
> +{
> +	struct drm_display_mode *mode = &encoder->crtc->mode;
> +	struct vc4_dsi_encoder *vc4_encoder = to_vc4_dsi_encoder(encoder);
> +	struct vc4_dsi *dsi = vc4_encoder->dsi;
> +	struct device *dev = &dsi->pdev->dev;
> +	u32 format = 0, divider = 0;
> +	bool debug_dump_regs = false;
> +	unsigned long hs_clock;
> +	u32 ui_ns;
> +	/* Minimum LP state duration in escape clock cycles. */
> +	u32 lpx = dsi_esc_timing(60);
> +	unsigned long pixel_clock_hz = mode->clock * 1000;
> +	unsigned long dsip_clock;
> +	unsigned long phy_clock;
> +	int ret;
> +
> +	ret = pm_runtime_get_sync(dev);
> +	if (ret) {
> +		DRM_ERROR("Failed to runtime PM enable on DSI%d\n", dsi->port);
> +		return;
> +	}
> +
> +	ret = drm_panel_prepare(dsi->panel);
> +	if (ret) {
> +		DRM_ERROR("Panel failed to prepare\n");
> +		return;
> +	}
> +
> +	if (debug_dump_regs) {
> +		DRM_INFO("DSI regs before:\n");
> +		vc4_dsi_dump_regs(dsi);
> +	}
> +
> +	switch (dsi->format) {
> +	case MIPI_DSI_FMT_RGB888:
> +		format = DSI_PFORMAT_RGB888;
> +		divider = 24 / dsi->lanes;
> +		break;
> +	case MIPI_DSI_FMT_RGB666:
> +		format = DSI_PFORMAT_RGB666;
> +		divider = 24 / dsi->lanes;
> +		break;
> +	case MIPI_DSI_FMT_RGB666_PACKED:
> +		format = DSI_PFORMAT_RGB666_PACKED;
> +		divider = 18 / dsi->lanes;
> +		break;
> +	case MIPI_DSI_FMT_RGB565:
> +		format = DSI_PFORMAT_RGB565;
> +		divider = 16 / dsi->lanes;
> +		break;
> +	}
> +
> +	phy_clock = pixel_clock_hz * divider;
> +	ret = clk_set_rate(dsi->pll_phy_clock, phy_clock);
> +	if (ret) {
> +		dev_err(&dsi->pdev->dev,
> +			"Failed to set phy clock to %ld: %d\n", phy_clock, ret);
> +	}
> +
> +	/* Reset the DSI and all its fifos. */
> +	DSI_PORT_WRITE(CTRL,
> +		       DSI_CTRL_SOFT_RESET_CFG |
> +		       DSI_PORT_BIT(CTRL_RESET_FIFOS));
> +
> +	DSI_PORT_WRITE(CTRL,
> +		       DSI_CTRL_HSDT_EOT_DISABLE |
> +		       DSI_CTRL_RX_LPDT_EOT_DISABLE);
> +
> +	/* Clear all stat bits so we see what has happened during enable. */
> +	DSI_PORT_WRITE(STAT, DSI_PORT_READ(STAT));
> +
> +	/* Set AFE CTR00/CTR1 to release powerdown of analog. */
> +	if (dsi->port == 0) {
> +		u32 afec0 = (VC4_SET_FIELD(7, DSI_PHY_AFEC0_PTATADJ) |
> +			     VC4_SET_FIELD(7, DSI_PHY_AFEC0_CTATADJ));
> +
> +		if (dsi->lanes < 2)
> +			afec0 |= DSI0_PHY_AFEC0_PD_DLANE1;
> +
> +		if (!(dsi->mode_flags & MIPI_DSI_MODE_VIDEO))
> +			afec0 |= DSI0_PHY_AFEC0_RESET;
> +
> +		DSI_PORT_WRITE(PHY_AFEC0, afec0);
> +
> +		DSI_PORT_WRITE(PHY_AFEC1,
> +			       VC4_SET_FIELD(6,  DSI0_PHY_AFEC1_IDR_DLANE1) |
> +			       VC4_SET_FIELD(6,  DSI0_PHY_AFEC1_IDR_DLANE0) |
> +			       VC4_SET_FIELD(6,  DSI0_PHY_AFEC1_IDR_CLANE));
> +	} else {
> +		u32 afec0 = (VC4_SET_FIELD(7, DSI_PHY_AFEC0_PTATADJ) |
> +			     VC4_SET_FIELD(7, DSI_PHY_AFEC0_CTATADJ) |
> +			     VC4_SET_FIELD(6, DSI1_PHY_AFEC0_IDR_CLANE) |
> +			     VC4_SET_FIELD(6, DSI1_PHY_AFEC0_IDR_DLANE0) |
> +			     VC4_SET_FIELD(6, DSI1_PHY_AFEC0_IDR_DLANE1) |
> +			     VC4_SET_FIELD(6, DSI1_PHY_AFEC0_IDR_DLANE2) |
> +			     VC4_SET_FIELD(6, DSI1_PHY_AFEC0_IDR_DLANE3));
> +
> +		if (dsi->lanes < 4)
> +			afec0 |= DSI1_PHY_AFEC0_PD_DLANE3;
> +		if (dsi->lanes < 3)
> +			afec0 |= DSI1_PHY_AFEC0_PD_DLANE2;
> +		if (dsi->lanes < 2)
> +			afec0 |= DSI1_PHY_AFEC0_PD_DLANE1;
> +
> +		afec0 |= DSI1_PHY_AFEC0_RESET;
> +
> +		DSI_PORT_WRITE(PHY_AFEC0, afec0);
> +
> +		DSI_PORT_WRITE(PHY_AFEC1, 0);
> +
> +		/* AFEC reset hold time */
> +		mdelay(1);
> +	}
> +
> +	ret = clk_prepare_enable(dsi->escape_clock);
> +	if (ret) {
> +		DRM_ERROR("Failed to turn on DSI escape clock: %d\n", ret);
> +		return;
> +	}
> +
> +	ret = clk_prepare_enable(dsi->pll_phy_clock);
> +	if (ret) {
> +		DRM_ERROR("Failed to turn on DSI PLL: %d\n", ret);
> +		return;
> +	}
> +
> +	hs_clock = clk_get_rate(dsi->pll_phy_clock);
> +
> +	/* Yes, we set the DSI0P/DSI1P pixel clock to the byte rate,
> +	 * not the pixel clock rate.  DSIxP take from the APHY's byte,
> +	 * DDR2, or DDR4 clock (we use byte) and feed into the PV at
> +	 * that rate.  Separately, a value derived from PIX_CLK_DIV
> +	 * and HS_CLKC is fed into the PV to divide down to the actual
> +	 * pixel clock for pushing pixels into DSI.
> +	 */
> +	dsip_clock = phy_clock / 8;
> +	ret = clk_set_rate(dsi->pixel_clock, dsip_clock);
> +	if (ret) {
> +		dev_err(dev, "Failed to set pixel clock to %ldHz: %d\n",
> +			dsip_clock, ret);
> +	}
> +
> +	ret = clk_prepare_enable(dsi->pixel_clock);
> +	if (ret) {
> +		DRM_ERROR("Failed to turn on DSI pixel clock: %d\n", ret);
> +		return;
> +	}
> +
> +	/* How many ns one DSI unit interval is.  Note that the clock
> +	 * is DDR, so there's an extra divide by 2.
> +	 */
> +	ui_ns = DIV_ROUND_UP(500000000, hs_clock);
> +
> +	DSI_PORT_WRITE(HS_CLT0,
> +		       VC4_SET_FIELD(dsi_hs_timing(ui_ns, 262, 0),
> +				     DSI_HS_CLT0_CZERO) |
> +		       VC4_SET_FIELD(dsi_hs_timing(ui_ns, 0, 8),
> +				     DSI_HS_CLT0_CPRE) |
> +		       VC4_SET_FIELD(dsi_hs_timing(ui_ns, 38, 0),
> +				     DSI_HS_CLT0_CPREP));
> +
> +	DSI_PORT_WRITE(HS_CLT1,
> +		       VC4_SET_FIELD(dsi_hs_timing(ui_ns, 60, 0),
> +				     DSI_HS_CLT1_CTRAIL) |
> +		       VC4_SET_FIELD(dsi_hs_timing(ui_ns, 60, 52),
> +				     DSI_HS_CLT1_CPOST));
> +
> +	DSI_PORT_WRITE(HS_CLT2,
> +		       VC4_SET_FIELD(dsi_hs_timing(ui_ns, 1000000, 0),
> +				     DSI_HS_CLT2_WUP));
> +
> +	DSI_PORT_WRITE(HS_DLT3,
> +		       VC4_SET_FIELD(dsi_hs_timing(ui_ns, 100, 0),
> +				     DSI_HS_DLT3_EXIT) |
> +		       VC4_SET_FIELD(dsi_hs_timing(ui_ns, 105, 6),
> +				     DSI_HS_DLT3_ZERO) |
> +		       VC4_SET_FIELD(dsi_hs_timing(ui_ns, 40, 4),
> +				     DSI_HS_DLT3_PRE));
> +
> +	DSI_PORT_WRITE(HS_DLT4,
> +		       VC4_SET_FIELD(dsi_hs_timing(ui_ns, lpx * ESC_TIME_NS, 0),
> +				     DSI_HS_DLT4_LPX) |
> +		       VC4_SET_FIELD(max(dsi_hs_timing(ui_ns, 0, 8),
> +					 dsi_hs_timing(ui_ns, 60, 4)),
> +				     DSI_HS_DLT4_TRAIL) |
> +		       VC4_SET_FIELD(0, DSI_HS_DLT4_ANLAT));
> +
> +	DSI_PORT_WRITE(HS_DLT5, VC4_SET_FIELD(dsi_hs_timing(ui_ns, 1000, 5000),
> +					      DSI_HS_DLT5_INIT));
> +
> +	DSI_PORT_WRITE(HS_DLT6,
> +		       VC4_SET_FIELD(lpx * 5, DSI_HS_DLT6_TA_GET) |
> +		       VC4_SET_FIELD(lpx, DSI_HS_DLT6_TA_SURE) |
> +		       VC4_SET_FIELD(lpx * 4, DSI_HS_DLT6_TA_GO) |
> +		       VC4_SET_FIELD(lpx, DSI_HS_DLT6_LP_LPX));
> +
> +	DSI_PORT_WRITE(HS_DLT7,
> +		       VC4_SET_FIELD(dsi_esc_timing(1000000),
> +				     DSI_HS_DLT7_LP_WUP));
> +
> +	DSI_PORT_WRITE(PHYC,
> +		       DSI_PHYC_DLANE0_ENABLE |
> +		       (dsi->lanes >= 2 ? DSI_PHYC_DLANE1_ENABLE : 0) |
> +		       (dsi->lanes >= 3 ? DSI_PHYC_DLANE2_ENABLE : 0) |
> +		       (dsi->lanes >= 4 ? DSI_PHYC_DLANE3_ENABLE : 0) |
> +		       DSI_PORT_BIT(PHYC_CLANE_ENABLE) |
> +		       ((dsi->mode_flags & MIPI_DSI_CLOCK_NON_CONTINUOUS) ?
> +			0 : DSI_PORT_BIT(PHYC_HS_CLK_CONTINUOUS)) |
> +		       (dsi->port == 0 ?
> +			VC4_SET_FIELD(lpx - 1, DSI0_PHYC_ESC_CLK_LPDT) :
> +			VC4_SET_FIELD(lpx - 1, DSI1_PHYC_ESC_CLK_LPDT)));
> +
> +	DSI_PORT_WRITE(CTRL,
> +		       DSI_PORT_READ(CTRL) |
> +		       DSI_CTRL_CAL_BYTE);
> +
> +	/* HS timeout in HS clock cycles: disabled. */
> +	DSI_PORT_WRITE(HSTX_TO_CNT, 0);
> +	/* LP receive timeout in HS clocks. */
> +	DSI_PORT_WRITE(LPRX_TO_CNT, 0xffffff);
> +	/* Bus turnaround timeout */
> +	DSI_PORT_WRITE(TA_TO_CNT, 100000);
> +	/* Display reset sequence timeout */
> +	DSI_PORT_WRITE(PR_TO_CNT, 100000);
> +
> +	if (dsi->mode_flags & MIPI_DSI_MODE_VIDEO) {
> +		DSI_PORT_WRITE(DISP0_CTRL,
> +			       VC4_SET_FIELD(divider, DSI_DISP0_PIX_CLK_DIV) |
> +			       VC4_SET_FIELD(format, DSI_DISP0_PFORMAT) |
> +			       VC4_SET_FIELD(DSI_DISP0_LP_STOP_PERFRAME,
> +					     DSI_DISP0_LP_STOP_CTRL) |
> +			       DSI_DISP0_ST_END |
> +			       DSI_DISP0_ENABLE);
> +	} else {
> +		DSI_PORT_WRITE(DISP0_CTRL,
> +			       DSI_DISP0_COMMAND_MODE |
> +			       DSI_DISP0_ENABLE);
> +	}
> +
> +	/* Set up DISP1 for transferring long command payloads through
> +	 * the pixfifo.
> +	 */
> +	DSI_PORT_WRITE(DISP1_CTRL,
> +		       VC4_SET_FIELD(DSI_DISP1_PFORMAT_32BIT_LE,
> +				     DSI_DISP1_PFORMAT) |
> +		       DSI_DISP1_ENABLE);
> +
> +	/* Ungate the block. */
> +	if (dsi->port == 0)
> +		DSI_PORT_WRITE(CTRL, DSI_PORT_READ(CTRL) | DSI0_CTRL_CTRL0);
> +	else
> +		DSI_PORT_WRITE(CTRL, DSI_PORT_READ(CTRL) | DSI1_CTRL_EN);
> +
> +	/* Bring AFE out of reset. */
> +	if (dsi->port == 0) {
> +	} else {
> +		DSI_PORT_WRITE(PHY_AFEC0,
> +			       DSI_PORT_READ(PHY_AFEC0) &
> +			       ~DSI1_PHY_AFEC0_RESET);
> +	}
> +
> +	vc4_dsi_ulps(dsi, false);
> +
> +	if (debug_dump_regs) {
> +		DRM_INFO("DSI regs after:\n");
> +		vc4_dsi_dump_regs(dsi);
> +	}
> +
> +	ret = drm_panel_enable(dsi->panel);
> +	if (ret) {
> +		DRM_ERROR("Panel failed to enable\n");
> +		drm_panel_unprepare(dsi->panel);
> +		return;
> +	}
> +}
> +
> +static ssize_t vc4_dsi_host_transfer(struct mipi_dsi_host *host,
> +				     const struct mipi_dsi_msg *msg)
> +{
> +	struct vc4_dsi *dsi = host_to_dsi(host);
> +	struct mipi_dsi_packet packet;
> +	u32 pkth = 0, pktc = 0;
> +	int i, ret;
> +	bool is_long = mipi_dsi_packet_format_is_long(msg->type);
> +	u32 cmd_fifo_len = 0, pix_fifo_len = 0;
> +
> +	mipi_dsi_create_packet(&packet, msg);
> +
> +	pkth |= VC4_SET_FIELD(packet.header[0], DSI_TXPKT1H_BC_DT);
> +	pkth |= VC4_SET_FIELD(packet.header[1] |
> +			      (packet.header[2] << 8),
> +			      DSI_TXPKT1H_BC_PARAM);
> +	if (is_long) {
> +		/* Divide data across the various FIFOs we have available.
> +		 * The command FIFO takes byte-oriented data, but is of
> +		 * limited size. The pixel FIFO (never actually used for
> +		 * pixel data in reality) is word oriented, and substantially
> +		 * larger. So, we use the pixel FIFO for most of the data,
> +		 * sending the residual bytes in the command FIFO at the start.
> +		 *
> +		 * With this arrangement, the command FIFO will never get full.
> +		 */

I wondered whether this is something the dsi core should maybe optionally
do, but doesn't seem to be a common pattern looking at existing transfer
functions.

> +		if (packet.payload_length <= 16) {
> +			cmd_fifo_len = packet.payload_length;
> +			pix_fifo_len = 0;
> +		} else {
> +			cmd_fifo_len = (packet.payload_length %
> +					DSI_PIX_FIFO_WIDTH);
> +			pix_fifo_len = ((packet.payload_length - cmd_fifo_len) /
> +					DSI_PIX_FIFO_WIDTH);
> +		}
> +
> +		WARN_ON_ONCE(pix_fifo_len >= DSI_PIX_FIFO_DEPTH);
> +
> +		pkth |= VC4_SET_FIELD(cmd_fifo_len, DSI_TXPKT1H_BC_CMDFIFO);
> +	}
> +
> +	if (msg->rx_len) {
> +		pktc |= VC4_SET_FIELD(DSI_TXPKT1C_CMD_CTRL_RX,
> +				      DSI_TXPKT1C_CMD_CTRL);
> +	} else {
> +		pktc |= VC4_SET_FIELD(DSI_TXPKT1C_CMD_CTRL_TX,
> +				      DSI_TXPKT1C_CMD_CTRL);
> +	}
> +
> +	for (i = 0; i < cmd_fifo_len; i++)
> +		DSI_PORT_WRITE(TXPKT_CMD_FIFO, packet.payload[i]);
> +	for (i = 0; i < pix_fifo_len; i++) {
> +		const u8 *pix = packet.payload + cmd_fifo_len + i * 4;
> +
> +		DSI_PORT_WRITE(TXPKT_PIX_FIFO,
> +			       pix[0] |
> +			       pix[1] << 8 |
> +			       pix[2] << 16 |
> +			       pix[3] << 24);
> +	}
> +
> +	if (msg->flags & MIPI_DSI_MSG_USE_LPM)
> +		pktc |= DSI_TXPKT1C_CMD_MODE_LP;
> +	if (is_long)
> +		pktc |= DSI_TXPKT1C_CMD_TYPE_LONG;
> +
> +	/* Send one copy of the packet.  Larger repeats are used for pixel
> +	 * data in command mode.
> +	 */
> +	pktc |= VC4_SET_FIELD(1, DSI_TXPKT1C_CMD_REPEAT);
> +
> +	pktc |= DSI_TXPKT1C_CMD_EN;
> +	if (pix_fifo_len) {
> +		pktc |= VC4_SET_FIELD(DSI_TXPKT1C_DISPLAY_NO_SECONDARY,
> +				      DSI_TXPKT1C_DISPLAY_NO);
> +	} else {
> +		pktc |= VC4_SET_FIELD(DSI_TXPKT1C_DISPLAY_NO_SHORT,
> +				      DSI_TXPKT1C_DISPLAY_NO);
> +	}
> +
> +	/* Enable the appropriate interrupt for the transfer completion. */
> +	dsi->xfer_result = 0;
> +	reinit_completion(&dsi->xfer_completion);
> +	DSI_PORT_WRITE(INT_STAT, DSI1_INT_TXPKT1_DONE | DSI1_INT_PHY_DIR_RTF);
> +	if (msg->rx_len) {
> +		DSI_PORT_WRITE(INT_EN, (DSI1_INTERRUPTS_ALWAYS_ENABLED |
> +					DSI1_INT_PHY_DIR_RTF));
> +	} else {
> +		DSI_PORT_WRITE(INT_EN, (DSI1_INTERRUPTS_ALWAYS_ENABLED |
> +					DSI1_INT_TXPKT1_DONE));
> +	}
> +
> +	/* Send the packet. */
> +	DSI_PORT_WRITE(TXPKT1H, pkth);
> +	DSI_PORT_WRITE(TXPKT1C, pktc);
> +
> +	if (!wait_for_completion_timeout(&dsi->xfer_completion,
> +					 msecs_to_jiffies(1000))) {
> +		dev_err(&dsi->pdev->dev, "transfer interrupt wait timeout");
> +		dev_err(&dsi->pdev->dev, "instat: 0x%08x\n",
> +			DSI_PORT_READ(INT_STAT));
> +		ret = -ETIMEDOUT;
> +	} else {
> +		ret = dsi->xfer_result;
> +	}
> +
> +	DSI_PORT_WRITE(INT_EN, DSI1_INTERRUPTS_ALWAYS_ENABLED);
> +
> +	if (ret)
> +		goto reset_fifo_and_return;
> +
> +	if (ret == 0 && msg->rx_len) {
> +		u32 rxpkt1h = DSI_PORT_READ(RXPKT1H);
> +		u8 *msg_rx = msg->rx_buf;
> +
> +		if (rxpkt1h & DSI_RXPKT1H_PKT_TYPE_LONG) {
> +			u32 rxlen = VC4_GET_FIELD(rxpkt1h,
> +						  DSI_RXPKT1H_BC_PARAM);
> +
> +			if (rxlen != msg->rx_len) {
> +				DRM_ERROR("DSI returned %db, expecting %db\n",
> +					  rxlen, (int)msg->rx_len);
> +				ret = -ENXIO;
> +				goto reset_fifo_and_return;
> +			}
> +
> +			for (i = 0; i < msg->rx_len; i++)
> +				msg_rx[i] = DSI_READ(DSI1_RXPKT_FIFO);
> +		} else {
> +			/* FINISHME: Handle AWER */
> +
> +			msg_rx[0] = VC4_GET_FIELD(rxpkt1h,
> +						  DSI_RXPKT1H_SHORT_0);
> +			if (msg->rx_len > 1) {
> +				msg_rx[1] = VC4_GET_FIELD(rxpkt1h,
> +							  DSI_RXPKT1H_SHORT_1);
> +			}
> +		}
> +	}
> +
> +	return ret;
> +
> +reset_fifo_and_return:
> +	DRM_ERROR("DSI transfer failed, resetting: %d\n", ret);
> +
> +	DSI_PORT_WRITE(TXPKT1C, DSI_PORT_READ(TXPKT1C) & ~DSI_TXPKT1C_CMD_EN);
> +	udelay(1);
> +	DSI_PORT_WRITE(CTRL,
> +		       DSI_PORT_READ(CTRL) |
> +		       DSI_PORT_BIT(CTRL_RESET_FIFOS));
> +
> +	DSI_PORT_WRITE(TXPKT1C, 0);
> +	DSI_PORT_WRITE(INT_EN, DSI1_INTERRUPTS_ALWAYS_ENABLED);
> +	return ret;
> +}
> +
> +static int vc4_dsi_host_attach(struct mipi_dsi_host *host,
> +			       struct mipi_dsi_device *device)
> +{
> +	struct vc4_dsi *dsi = host_to_dsi(host);
> +	int ret = 0;
> +
> +	dsi->lanes = device->lanes;
> +	dsi->channel = device->channel;
> +	dsi->format = device->format;
> +	dsi->mode_flags = device->mode_flags;
> +
> +	if (!(dsi->mode_flags & MIPI_DSI_MODE_VIDEO)) {
> +		dev_err(&dsi->pdev->dev,
> +			"Only VIDEO mode panels supported currently.\n");
> +		return 0;
> +	}
> +
> +	dsi->panel = of_drm_find_panel(device->dev.of_node);
> +	if (!dsi->panel)
> +		return 0;
> +
> +	ret = drm_panel_attach(dsi->panel, dsi->connector);
> +	if (ret != 0)
> +		return ret;
> +
> +	drm_helper_hpd_irq_event(dsi->connector->dev);
> +
> +	return 0;
> +}
> +
> +static int vc4_dsi_host_detach(struct mipi_dsi_host *host,
> +			       struct mipi_dsi_device *device)
> +{
> +	struct vc4_dsi *dsi = host_to_dsi(host);
> +
> +	if (dsi->panel) {
> +		int ret = drm_panel_detach(dsi->panel);
> +
> +		if (ret)
> +			return ret;
> +
> +		dsi->panel = NULL;
> +
> +		drm_helper_hpd_irq_event(dsi->connector->dev);
> +	}
> +
> +	return 0;
> +}
> +
> +static const struct mipi_dsi_host_ops vc4_dsi_host_ops = {
> +	.attach = vc4_dsi_host_attach,
> +	.detach = vc4_dsi_host_detach,

There seems to be a lot of cargo-culting going on with attach/detach, and
I get a bit the feeling that refactoring this into a standard way to do it
(including the of/dt boilerplate, with an eye towards standardizing the
bindinds) would be good.

Also, proper kerneldoc for these callbacks instead of the onelines (we can
do multiline inline comments now, with formatting!) would be great.

> +	.transfer = vc4_dsi_host_transfer,

hisilicon doesn't even have a transfer function, I guess it works by
magic.

> +};
> +
> +static const struct drm_encoder_helper_funcs vc4_dsi_encoder_helper_funcs = {
> +	.disable = vc4_dsi_encoder_disable,
> +	.enable = vc4_dsi_encoder_enable,
> +};
> +
> +static const struct of_device_id vc4_dsi_dt_match[] = {
> +	{ .compatible = "brcm,bcm2835-dsi1", (void *)(uintptr_t)1 },
> +	{}
> +};
> +
> +static void dsi_handle_error(struct vc4_dsi *dsi,
> +			     irqreturn_t *ret, u32 stat, u32 bit,
> +			     const char *type)
> +{
> +	if (!(stat & bit))
> +		return;
> +
> +	DRM_ERROR("DSI%d: %s error\n", dsi->port, type);
> +	*ret = IRQ_HANDLED;
> +}
> +
> +static irqreturn_t vc4_dsi_irq_handler(int irq, void *data)
> +{
> +	struct vc4_dsi *dsi = data;
> +	u32 stat = DSI_PORT_READ(INT_STAT);
> +	irqreturn_t ret = IRQ_NONE;
> +
> +	DSI_PORT_WRITE(INT_STAT, stat);
> +
> +	dsi_handle_error(dsi, &ret, stat,
> +			 DSI1_INT_ERR_SYNC_ESC, "LPDT sync");
> +	dsi_handle_error(dsi, &ret, stat,
> +			 DSI1_INT_ERR_CONTROL, "data lane 0 sequence");
> +	dsi_handle_error(dsi, &ret, stat,
> +			 DSI1_INT_ERR_CONT_LP0, "LP0 contention");
> +	dsi_handle_error(dsi, &ret, stat,
> +			 DSI1_INT_ERR_CONT_LP1, "LP1 contention");
> +	dsi_handle_error(dsi, &ret, stat,
> +			 DSI1_INT_HSTX_TO, "HSTX timeout");
> +	dsi_handle_error(dsi, &ret, stat,
> +			 DSI1_INT_LPRX_TO, "LPRX timeout");
> +	dsi_handle_error(dsi, &ret, stat,
> +			 DSI1_INT_TA_TO, "turnaround timeout");
> +	dsi_handle_error(dsi, &ret, stat,
> +			 DSI1_INT_PR_TO, "peripheral reset timeout");
> +
> +	if (stat & (DSI1_INT_TXPKT1_DONE | DSI1_INT_PHY_DIR_RTF)) {
> +		complete(&dsi->xfer_completion);
> +		ret = IRQ_HANDLED;
> +	} else if (stat & DSI1_INT_HSTX_TO) {
> +		complete(&dsi->xfer_completion);
> +		dsi->xfer_result = -ETIMEDOUT;
> +		ret = IRQ_HANDLED;
> +	}
> +
> +	return ret;
> +}
> +
> +/**
> + * Exposes clocks generated by the analog PHY that are consumed by
> + * CPRMAN (clk-bcm2835.c).
> + */
> +static int
> +vc4_dsi_init_phy_clocks(struct vc4_dsi *dsi)
> +{
> +	struct device *dev = &dsi->pdev->dev;
> +	const char *parent_name = __clk_get_name(dsi->pll_phy_clock);
> +	static const struct {
> +		const char *dsi0_name, *dsi1_name;
> +		int div;
> +	} phy_clocks[] = {
> +		{ "dsi0_byte", "dsi1_byte", 8 },
> +		{ "dsi0_ddr2", "dsi1_ddr2", 4 },
> +		{ "dsi0_ddr", "dsi1_ddr", 2 },
> +	};
> +	int i;
> +
> +	dsi->clk_onecell.clk_num = ARRAY_SIZE(phy_clocks);
> +	dsi->clk_onecell.clks = devm_kcalloc(dev,
> +					     dsi->clk_onecell.clk_num,
> +					     sizeof(*dsi->clk_onecell.clks),
> +					     GFP_KERNEL);
> +	if (!dsi->clk_onecell.clks)
> +		return -ENOMEM;
> +
> +	for (i = 0; i < ARRAY_SIZE(phy_clocks); i++) {
> +		struct clk_fixed_factor *fix = &dsi->phy_clocks[i];
> +		struct clk_init_data init;
> +		struct clk *clk;
> +
> +		/* We just use core fixed factor clock ops for the PHY
> +		 * clocks.  The clocks are actually gated by the
> +		 * PHY_AFEC0_DDRCLK_EN bits, which we should be
> +		 * setting if we use the DDR/DDR2 clocks.  However,
> +		 * vc4_dsi_encoder_enable() is setting up both AFEC0,
> +		 * setting both our parent DSI PLL's rate and this
> +		 * clock's rate, so it knows if DDR/DDR2 are going to
> +		 * be used and could enable the gates itself.
> +		 */
> +		fix->mult = 1;
> +		fix->div = phy_clocks[i].div;
> +		fix->hw.init = &init;
> +
> +		memset(&init, 0, sizeof(init));
> +		init.parent_names = &parent_name;
> +		init.num_parents = 1;
> +		if (dsi->port == 1)
> +			init.name = phy_clocks[i].dsi1_name;
> +		else
> +			init.name = phy_clocks[i].dsi0_name;
> +		init.ops = &clk_fixed_factor_ops;
> +		init.flags = CLK_IS_BASIC;
> +
> +		clk = devm_clk_register(dev, &fix->hw);
> +		if (IS_ERR(clk))
> +			return PTR_ERR(clk);
> +
> +		dsi->clk_onecell.clks[i] = clk;
> +	}
> +
> +	return of_clk_add_provider(dev->of_node,
> +				   of_clk_src_onecell_get,
> +				   &dsi->clk_onecell);
> +}
> +
> +static int vc4_dsi_bind(struct device *dev, struct device *master, void *data)
> +{
> +	struct platform_device *pdev = to_platform_device(dev);
> +	struct drm_device *drm = dev_get_drvdata(master);
> +	struct vc4_dev *vc4 = to_vc4_dev(drm);
> +	struct vc4_dsi *dsi;
> +	struct vc4_dsi_encoder *vc4_dsi_encoder;
> +	const struct of_device_id *match;
> +	dma_cap_mask_t dma_mask;
> +	int ret;
> +
> +	dsi = devm_kzalloc(dev, sizeof(*dsi), GFP_KERNEL);
> +	if (!dsi)
> +		return -ENOMEM;
> +
> +	match = of_match_device(vc4_dsi_dt_match, dev);
> +	if (!match)
> +		return -ENODEV;
> +
> +	dsi->port = (uintptr_t)match->data;
> +
> +	vc4_dsi_encoder = devm_kzalloc(dev, sizeof(*vc4_dsi_encoder),
> +				       GFP_KERNEL);
> +	if (!vc4_dsi_encoder)
> +		return -ENOMEM;
> +	vc4_dsi_encoder->base.type = VC4_ENCODER_TYPE_DSI1;
> +	vc4_dsi_encoder->dsi = dsi;
> +	dsi->encoder = &vc4_dsi_encoder->base.base;
> +
> +	dsi->pdev = pdev;
> +	dsi->regs = vc4_ioremap_regs(pdev, 0);
> +	if (IS_ERR(dsi->regs))
> +		return PTR_ERR(dsi->regs);
> +
> +	if (DSI_PORT_READ(ID) != DSI_ID_VALUE) {
> +		dev_err(dev, "Port returned 0x%08x for ID instead of 0x%08x\n",
> +			DSI_PORT_READ(ID), DSI_ID_VALUE);
> +		return -ENODEV;
> +	}
> +
> +	/* DSI1 has a broken AXI slave that doesn't respond to writes
> +	 * from the ARM.  It does handle writes from the DMA engine,
> +	 * so set up a channel for talking to it.
> +	 */
> +	if (dsi->port == 1) {
> +		dsi->reg_dma_mem = dma_alloc_coherent(dev, 4,
> +						      &dsi->reg_dma_paddr,
> +						      GFP_KERNEL);
> +		if (!dsi->reg_dma_mem) {
> +			DRM_ERROR("Failed to get DMA memory\n");
> +			return -ENOMEM;
> +		}
> +
> +		dma_cap_zero(dma_mask);
> +		dma_cap_set(DMA_MEMCPY, dma_mask);
> +		dsi->reg_dma_chan = dma_request_chan_by_mask(&dma_mask);
> +		if (IS_ERR(dsi->reg_dma_chan)) {
> +			ret = PTR_ERR(dsi->reg_dma_chan);
> +			if (ret != -EPROBE_DEFER)
> +				DRM_ERROR("Failed to get DMA channel: %d\n",
> +					  ret);
> +			return ret;
> +		}
> +
> +		/* Get the physical address of the device's registers.  The
> +		 * struct resource for the regs gives us the bus address
> +		 * instead.
> +		 */
> +		dsi->reg_paddr = be32_to_cpup(of_get_address(dev->of_node,
> +							     0, NULL, NULL));
> +	}
> +
> +	init_completion(&dsi->xfer_completion);
> +	/* At startup enable error-reporting interrupts and nothing else. */
> +	DSI_PORT_WRITE(INT_EN, DSI1_INTERRUPTS_ALWAYS_ENABLED);
> +	/* Clear any existing interrupt state. */
> +	DSI_PORT_WRITE(INT_STAT, DSI_PORT_READ(INT_STAT));
> +
> +	ret = devm_request_irq(dev, platform_get_irq(pdev, 0),
> +			       vc4_dsi_irq_handler, 0, "vc4 dsi", dsi);
> +	if (ret) {
> +		if (ret != -EPROBE_DEFER)
> +			dev_err(dev, "Failed to get interrupt: %d\n", ret);
> +		return ret;
> +	}
> +
> +	dsi->escape_clock = devm_clk_get(dev, "escape");
> +	if (IS_ERR(dsi->escape_clock)) {
> +		ret = PTR_ERR(dsi->escape_clock);
> +		if (ret != -EPROBE_DEFER)
> +			dev_err(dev, "Failed to get escape clock: %d\n", ret);
> +		return ret;
> +	}
> +
> +	dsi->pll_phy_clock = devm_clk_get(dev, "phy");
> +	if (IS_ERR(dsi->pll_phy_clock)) {
> +		ret = PTR_ERR(dsi->pll_phy_clock);
> +		if (ret != -EPROBE_DEFER)
> +			dev_err(dev, "Failed to get phy clock: %d\n", ret);
> +		return ret;
> +	}
> +
> +	dsi->pixel_clock = devm_clk_get(dev, "pixel");
> +	if (IS_ERR(dsi->pixel_clock)) {
> +		ret = PTR_ERR(dsi->pixel_clock);
> +		if (ret != -EPROBE_DEFER)
> +			dev_err(dev, "Failed to get pixel clock: %d\n", ret);
> +		return ret;
> +	}
> +
> +	/* The esc clock rate is supposed to always be 100Mhz. */
> +	ret = clk_set_rate(dsi->escape_clock, 100 * 1000000);
> +	if (ret) {
> +		dev_err(dev, "Failed to set esc clock: %d\n", ret);
> +		return ret;
> +	}
> +
> +	ret = vc4_dsi_init_phy_clocks(dsi);
> +	if (ret)
> +		return ret;
> +
> +	if (dsi->port == 1)
> +		vc4->dsi1 = dsi;
> +
> +	drm_encoder_init(drm, dsi->encoder, &vc4_dsi_encoder_funcs,
> +			 DRM_MODE_ENCODER_DSI, NULL);
> +	drm_encoder_helper_add(dsi->encoder, &vc4_dsi_encoder_helper_funcs);
> +
> +	dsi->connector = vc4_dsi_connector_init(drm, dsi);
> +	if (IS_ERR(dsi->connector)) {
> +		ret = PTR_ERR(dsi->connector);
> +		goto err_destroy_encoder;
> +	}
> +
> +	dsi->dsi_host.ops = &vc4_dsi_host_ops;
> +	dsi->dsi_host.dev = dev;
> +
> +	mipi_dsi_host_register(&dsi->dsi_host);
> +
> +	dev_set_drvdata(dev, dsi);
> +
> +	pm_runtime_enable(dev);
> +
> +	return 0;
> +
> +err_destroy_encoder:
> +	vc4_dsi_encoder_destroy(dsi->encoder);
> +
> +	return ret;
> +}
> +
> +static void vc4_dsi_unbind(struct device *dev, struct device *master,
> +			   void *data)
> +{
> +	struct drm_device *drm = dev_get_drvdata(master);
> +	struct vc4_dev *vc4 = to_vc4_dev(drm);
> +	struct vc4_dsi *dsi = dev_get_drvdata(dev);
> +
> +	pm_runtime_disable(dev);
> +
> +	vc4_dsi_connector_destroy(dsi->connector);
> +	vc4_dsi_encoder_destroy(dsi->encoder);
> +
> +	mipi_dsi_host_unregister(&dsi->dsi_host);
> +
> +	clk_disable_unprepare(dsi->pll_phy_clock);
> +	clk_disable_unprepare(dsi->escape_clock);
> +
> +	if (dsi->port == 1)
> +		vc4->dsi1 = NULL;
> +}
> +
> +static const struct component_ops vc4_dsi_ops = {
> +	.bind   = vc4_dsi_bind,
> +	.unbind = vc4_dsi_unbind,
> +};
> +
> +static int vc4_dsi_dev_probe(struct platform_device *pdev)
> +{
> +	return component_add(&pdev->dev, &vc4_dsi_ops);
> +}
> +
> +static int vc4_dsi_dev_remove(struct platform_device *pdev)
> +{
> +	component_del(&pdev->dev, &vc4_dsi_ops);
> +	return 0;
> +}
> +
> +struct platform_driver vc4_dsi_driver = {
> +	.probe = vc4_dsi_dev_probe,
> +	.remove = vc4_dsi_dev_remove,
> +	.driver = {
> +		.name = "vc4_dsi",
> +		.of_match_table = vc4_dsi_dt_match,
> +	},
> +};
> -- 
> 2.11.0
> 
> _______________________________________________
> dri-devel mailing list
> dri-devel at lists.freedesktop.org
> https://lists.freedesktop.org/mailman/listinfo/dri-devel

-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch



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