drm/bridge: Add NWL MIPI DSI host controller support

This adds initial support for the NWL MIPI DSI Host controller found on
i.MX8 SoCs.

It adds support for the i.MX8MQ but the same IP can be found on
e.g. the i.MX8QXP.

It has been tested on the Librem 5 devkit using mxsfb.

Signed-off-by: Guido Günther <agx@sigxcpu.org>
Co-developed-by: Robert Chiras <robert.chiras@nxp.com>
Signed-off-by: Robert Chiras <robert.chiras@nxp.com>
Tested-by: Robert Chiras <robert.chiras@nxp.com>
Tested-by: Martin Kepplinger <martin.kepplinger@puri.sm>
Reviewed-by: Fabio Estevam <festevam@gmail.com>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/1cf5750f734e33d005564cd89c576eaf3c1c192b.1586427783.git.agx@sigxcpu.org

drivers/gpu/drm/bridge/Kconfig

@@ -58,6 +58,22 @@ config DRM_MEGACHIPS_STDPXXXX_GE_B850V3_FW
 	  to DP++. This is used with the i.MX6 imx-ldb
 	  driver. You are likely to say N here.
 
+config DRM_NWL_MIPI_DSI
+	tristate "Northwest Logic MIPI DSI Host controller"
+	depends on DRM
+	depends on COMMON_CLK
+	depends on OF && HAS_IOMEM
+	select DRM_KMS_HELPER
+	select DRM_MIPI_DSI
+	select DRM_PANEL_BRIDGE
+	select GENERIC_PHY_MIPI_DPHY
+	select MFD_SYSCON
+	select MULTIPLEXER
+	select REGMAP_MMIO
+	help
+	  This enables the Northwest Logic MIPI DSI Host controller as
+	  for example found on NXP's i.MX8 Processors.
+
 config DRM_NXP_PTN3460
 	tristate "NXP PTN3460 DP/LVDS bridge"
 	depends on OF

drivers/gpu/drm/bridge/Makefile

@@ -18,6 +18,7 @@ obj-$(CONFIG_DRM_I2C_ADV7511) += adv7511/
 obj-$(CONFIG_DRM_TI_SN65DSI86) += ti-sn65dsi86.o
 obj-$(CONFIG_DRM_TI_TFP410) += ti-tfp410.o
 obj-$(CONFIG_DRM_TI_TPD12S015) += ti-tpd12s015.o
+obj-$(CONFIG_DRM_NWL_MIPI_DSI) += nwl-dsi.o
 
 obj-y += analogix/
 obj-y += synopsys/

drivers/gpu/drm/bridge/nwl-dsi.h

+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * NWL MIPI DSI host driver
+ *
+ * Copyright (C) 2017 NXP
+ * Copyright (C) 2019 Purism SPC
+ */
+#ifndef __NWL_DSI_H__
+#define __NWL_DSI_H__
+
+/* DSI HOST registers */
+#define NWL_DSI_CFG_NUM_LANES			0x0
+#define NWL_DSI_CFG_NONCONTINUOUS_CLK		0x4
+#define NWL_DSI_CFG_T_PRE			0x8
+#define NWL_DSI_CFG_T_POST			0xc
+#define NWL_DSI_CFG_TX_GAP			0x10
+#define NWL_DSI_CFG_AUTOINSERT_EOTP		0x14
+#define NWL_DSI_CFG_EXTRA_CMDS_AFTER_EOTP	0x18
+#define NWL_DSI_CFG_HTX_TO_COUNT		0x1c
+#define NWL_DSI_CFG_LRX_H_TO_COUNT		0x20
+#define NWL_DSI_CFG_BTA_H_TO_COUNT		0x24
+#define NWL_DSI_CFG_TWAKEUP			0x28
+#define NWL_DSI_CFG_STATUS_OUT			0x2c
+#define NWL_DSI_RX_ERROR_STATUS			0x30
+
+/* DSI DPI registers */
+#define NWL_DSI_PIXEL_PAYLOAD_SIZE		0x200
+#define NWL_DSI_PIXEL_FIFO_SEND_LEVEL		0x204
+#define NWL_DSI_INTERFACE_COLOR_CODING		0x208
+#define NWL_DSI_PIXEL_FORMAT			0x20c
+#define NWL_DSI_VSYNC_POLARITY			0x210
+#define NWL_DSI_VSYNC_POLARITY_ACTIVE_LOW	0
+#define NWL_DSI_VSYNC_POLARITY_ACTIVE_HIGH	BIT(1)
+
+#define NWL_DSI_HSYNC_POLARITY			0x214
+#define NWL_DSI_HSYNC_POLARITY_ACTIVE_LOW	0
+#define NWL_DSI_HSYNC_POLARITY_ACTIVE_HIGH	BIT(1)
+
+#define NWL_DSI_VIDEO_MODE			0x218
+#define NWL_DSI_HFP				0x21c
+#define NWL_DSI_HBP				0x220
+#define NWL_DSI_HSA				0x224
+#define NWL_DSI_ENABLE_MULT_PKTS		0x228
+#define NWL_DSI_VBP				0x22c
+#define NWL_DSI_VFP				0x230
+#define NWL_DSI_BLLP_MODE			0x234
+#define NWL_DSI_USE_NULL_PKT_BLLP		0x238
+#define NWL_DSI_VACTIVE				0x23c
+#define NWL_DSI_VC				0x240
+
+/* DSI APB PKT control */
+#define NWL_DSI_TX_PAYLOAD			0x280
+#define NWL_DSI_PKT_CONTROL			0x284
+#define NWL_DSI_SEND_PACKET			0x288
+#define NWL_DSI_PKT_STATUS			0x28c
+#define NWL_DSI_PKT_FIFO_WR_LEVEL		0x290
+#define NWL_DSI_PKT_FIFO_RD_LEVEL		0x294
+#define NWL_DSI_RX_PAYLOAD			0x298
+#define NWL_DSI_RX_PKT_HEADER			0x29c
+
+/* DSI IRQ handling */
+#define NWL_DSI_IRQ_STATUS			0x2a0
+#define NWL_DSI_SM_NOT_IDLE			BIT(0)
+#define NWL_DSI_TX_PKT_DONE			BIT(1)
+#define NWL_DSI_DPHY_DIRECTION			BIT(2)
+#define NWL_DSI_TX_FIFO_OVFLW			BIT(3)
+#define NWL_DSI_TX_FIFO_UDFLW			BIT(4)
+#define NWL_DSI_RX_FIFO_OVFLW			BIT(5)
+#define NWL_DSI_RX_FIFO_UDFLW			BIT(6)
+#define NWL_DSI_RX_PKT_HDR_RCVD			BIT(7)
+#define NWL_DSI_RX_PKT_PAYLOAD_DATA_RCVD	BIT(8)
+#define NWL_DSI_BTA_TIMEOUT			BIT(29)
+#define NWL_DSI_LP_RX_TIMEOUT			BIT(30)
+#define NWL_DSI_HS_TX_TIMEOUT			BIT(31)
+
+#define NWL_DSI_IRQ_STATUS2			0x2a4
+#define NWL_DSI_SINGLE_BIT_ECC_ERR		BIT(0)
+#define NWL_DSI_MULTI_BIT_ECC_ERR		BIT(1)
+#define NWL_DSI_CRC_ERR				BIT(2)
+
+#define NWL_DSI_IRQ_MASK			0x2a8
+#define NWL_DSI_SM_NOT_IDLE_MASK		BIT(0)
+#define NWL_DSI_TX_PKT_DONE_MASK		BIT(1)
+#define NWL_DSI_DPHY_DIRECTION_MASK		BIT(2)
+#define NWL_DSI_TX_FIFO_OVFLW_MASK		BIT(3)
+#define NWL_DSI_TX_FIFO_UDFLW_MASK		BIT(4)
+#define NWL_DSI_RX_FIFO_OVFLW_MASK		BIT(5)
+#define NWL_DSI_RX_FIFO_UDFLW_MASK		BIT(6)
+#define NWL_DSI_RX_PKT_HDR_RCVD_MASK		BIT(7)
+#define NWL_DSI_RX_PKT_PAYLOAD_DATA_RCVD_MASK	BIT(8)
+#define NWL_DSI_BTA_TIMEOUT_MASK		BIT(29)
+#define NWL_DSI_LP_RX_TIMEOUT_MASK		BIT(30)
+#define NWL_DSI_HS_TX_TIMEOUT_MASK		BIT(31)
+
+#define NWL_DSI_IRQ_MASK2			0x2ac
+#define NWL_DSI_SINGLE_BIT_ECC_ERR_MASK		BIT(0)
+#define NWL_DSI_MULTI_BIT_ECC_ERR_MASK		BIT(1)
+#define NWL_DSI_CRC_ERR_MASK			BIT(2)
+
+/*
+ * PKT_CONTROL format:
+ * [15: 0] - word count
+ * [17:16] - virtual channel
+ * [23:18] - data type
+ * [24]	   - LP or HS select (0 - LP, 1 - HS)
+ * [25]	   - perform BTA after packet is sent
+ * [26]	   - perform BTA only, no packet tx
+ */
+#define NWL_DSI_WC(x)		FIELD_PREP(GENMASK(15, 0), (x))
+#define NWL_DSI_TX_VC(x)	FIELD_PREP(GENMASK(17, 16), (x))
+#define NWL_DSI_TX_DT(x)	FIELD_PREP(GENMASK(23, 18), (x))
+#define NWL_DSI_HS_SEL(x)	FIELD_PREP(GENMASK(24, 24), (x))
+#define NWL_DSI_BTA_TX(x)	FIELD_PREP(GENMASK(25, 25), (x))
+#define NWL_DSI_BTA_NO_TX(x)	FIELD_PREP(GENMASK(26, 26), (x))
+
+/*
+ * RX_PKT_HEADER format:
+ * [15: 0] - word count
+ * [21:16] - data type
+ * [23:22] - virtual channel
+ */
+#define NWL_DSI_RX_DT(x)	FIELD_GET(GENMASK(21, 16), (x))
+#define NWL_DSI_RX_VC(x)	FIELD_GET(GENMASK(23, 22), (x))
+
+/* DSI Video mode */
+#define NWL_DSI_VM_BURST_MODE_WITH_SYNC_PULSES		0
+#define NWL_DSI_VM_NON_BURST_MODE_WITH_SYNC_EVENTS	BIT(0)
+#define NWL_DSI_VM_BURST_MODE				BIT(1)
+
+/* * DPI color coding */
+#define NWL_DSI_DPI_16_BIT_565_PACKED	0
+#define NWL_DSI_DPI_16_BIT_565_ALIGNED	1
+#define NWL_DSI_DPI_16_BIT_565_SHIFTED	2
+#define NWL_DSI_DPI_18_BIT_PACKED	3
+#define NWL_DSI_DPI_18_BIT_ALIGNED	4
+#define NWL_DSI_DPI_24_BIT		5
+
+/* * DPI Pixel format */
+#define NWL_DSI_PIXEL_FORMAT_16  0
+#define NWL_DSI_PIXEL_FORMAT_18  BIT(0)
+#define NWL_DSI_PIXEL_FORMAT_18L BIT(1)
+#define NWL_DSI_PIXEL_FORMAT_24  (BIT(0) | BIT(1))
+
+#endif /* __NWL_DSI_H__ */