[media] VPU: mediatek: support Mediatek VPU

The VPU driver for hw video codec embedded in Mediatek's MT8173 SOCs.
It is able to handle video decoding/encoding of in a range of formats.
The driver provides with VPU firmware download, memory management and
the communication interface between CPU and VPU.
For VPU initialization, it will create virtual memory for CPU access and
IOMMU address for vcodec hw device access. When a decode/encode instance
opens a device node, vpu driver will download vpu firmware to the device.
A decode/encode instant will decode/encode a frame using VPU
interface to interrupt vpu to handle decoding/encoding jobs.
Signed-off-by: Andrew-CT Chen <andrew-ct.chen@mediatek.com>
Signed-off-by: Tiffany Lin <tiffany.lin@mediatek.com>
[hans.verkuil@cisco.com: drop unnecessary ARM || ARM64 dependency]
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

drivers/media/platform/Kconfig

@@ -153,6 +153,19 @@ config VIDEO_CODA
 	   Coda is a range of video codec IPs that supports
 	   H.264, MPEG-4, and other video formats.
 
+config VIDEO_MEDIATEK_VPU
+	tristate "Mediatek Video Processor Unit"
+	depends on VIDEO_DEV && VIDEO_V4L2
+	depends on ARCH_MEDIATEK || COMPILE_TEST
+	---help---
+	    This driver provides downloading VPU firmware and
+	    communicating with VPU. This driver for hw video
+	    codec embedded in Mediatek's MT8173 SOCs. It is able
+	    to handle video decoding/encoding in a range of formats.
+
+	    To compile this driver as a module, choose M here: the
+	    module will be called mtk-vpu.
+
 config VIDEO_MEM2MEM_DEINTERLACE
 	tristate "Deinterlace support"
 	depends on VIDEO_DEV && VIDEO_V4L2 && DMA_ENGINE

drivers/media/platform/Makefile

@@ -58,3 +58,5 @@ obj-$(CONFIG_VIDEO_XILINX)		+= xilinx/
 obj-$(CONFIG_VIDEO_RCAR_VIN)		+= rcar-vin/
 
 ccflags-y += -I$(srctree)/drivers/media/i2c
+
+obj-$(CONFIG_VIDEO_MEDIATEK_VPU)	+= mtk-vpu/

drivers/media/platform/mtk-vpu/Makefile

+mtk-vpu-y += mtk_vpu.o
+
+obj-$(CONFIG_VIDEO_MEDIATEK_VPU) += mtk-vpu.o

drivers/media/platform/mtk-vpu/mtk_vpu.h

+/*
+* Copyright (c) 2016 MediaTek Inc.
+* Author: Andrew-CT Chen <andrew-ct.chen@mediatek.com>
+*
+* 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.
+*/
+
+#ifndef _MTK_VPU_H
+#define _MTK_VPU_H
+
+#include <linux/platform_device.h>
+
+/**
+ * VPU (video processor unit) is a tiny processor controlling video hardware
+ * related to video codec, scaling and color format converting.
+ * VPU interfaces with other blocks by share memory and interrupt.
+ **/
+
+typedef void (*ipi_handler_t) (void *data,
+			       unsigned int len,
+			       void *priv);
+
+/**
+ * enum ipi_id - the id of inter-processor interrupt
+ *
+ * @IPI_VPU_INIT:	 The interrupt from vpu is to notfiy kernel
+			 VPU initialization completed.
+			 IPI_VPU_INIT is sent from VPU when firmware is
+			 loaded. AP doesn't need to send IPI_VPU_INIT
+			 command to VPU.
+			 For other IPI below, AP should send the request
+			 to VPU to trigger the interrupt.
+ * @IPI_VENC_H264:	 The interrupt from vpu is to notify kernel to
+			 handle H264 video encoder job, and vice versa.
+ * @IPI_VENC_VP8:	 The interrupt fro vpu is to notify kernel to
+			 handle VP8 video encoder job,, and vice versa.
+ * @IPI_MAX:		 The maximum IPI number
+ */
+
+enum ipi_id {
+	IPI_VPU_INIT = 0,
+	IPI_VENC_H264,
+	IPI_VENC_VP8,
+	IPI_MAX,
+};
+
+/**
+ * enum rst_id - reset id to register reset function for VPU watchdog timeout
+ *
+ * @VPU_RST_ENC: encoder reset id
+ * @VPU_RST_MAX: maximum reset id
+ */
+enum rst_id {
+	VPU_RST_ENC,
+	VPU_RST_MAX,
+};
+
+/**
+ * vpu_ipi_register - register an ipi function
+ *
+ * @pdev:	VPU platform device
+ * @id:		IPI ID
+ * @handler:	IPI handler
+ * @name:	IPI name
+ * @priv:	private data for IPI handler
+ *
+ * Register an ipi function to receive ipi interrupt from VPU.
+ *
+ * Return: Return 0 if ipi registers successfully, otherwise it is failed.
+ */
+int vpu_ipi_register(struct platform_device *pdev, enum ipi_id id,
+		     ipi_handler_t handler, const char *name, void *priv);
+
+/**
+ * vpu_ipi_send - send data from AP to vpu.
+ *
+ * @pdev:	VPU platform device
+ * @id:		IPI ID
+ * @buf:	the data buffer
+ * @len:	the data buffer length
+ *
+ * This function is thread-safe. When this function returns,
+ * VPU has received the data and starts the processing.
+ * When the processing completes, IPI handler registered
+ * by vpu_ipi_register will be called in interrupt context.
+ *
+ * Return: Return 0 if sending data successfully, otherwise it is failed.
+ **/
+int vpu_ipi_send(struct platform_device *pdev,
+		 enum ipi_id id, void *buf,
+		 unsigned int len);
+
+/**
+ * vpu_get_plat_device - get VPU's platform device
+ *
+ * @pdev:	the platform device of the module requesting VPU platform
+ *		device for using VPU API.
+ *
+ * Return: Return NULL if it is failed.
+ * otherwise it is VPU's platform device
+ **/
+struct platform_device *vpu_get_plat_device(struct platform_device *pdev);
+
+/**
+ * vpu_wdt_reg_handler - register a VPU watchdog handler
+ *
+ * @pdev:               VPU platform device
+ * @vpu_wdt_reset_func:	the callback reset function
+ * @private_data:       the private data for reset function
+ * @rst_id:		reset id
+ *
+ * Register a handler performing own tasks when vpu reset by watchdog
+ *
+ * Return: Return 0 if the handler is added successfully,
+ * otherwise it is failed.
+ *
+ **/
+int vpu_wdt_reg_handler(struct platform_device *pdev,
+			void vpu_wdt_reset_func(void *),
+			void *priv, enum rst_id id);
+/**
+ * vpu_get_venc_hw_capa - get video encoder hardware capability
+ *
+ * @pdev:	VPU platform device
+ *
+ * Return: video encoder hardware capability
+ **/
+unsigned int vpu_get_venc_hw_capa(struct platform_device *pdev);
+
+/**
+ * vpu_load_firmware - download VPU firmware and boot it
+ *
+ * @pdev:	VPU platform device
+ *
+ * Return: Return 0 if downloading firmware successfully,
+ * otherwise it is failed
+ **/
+int vpu_load_firmware(struct platform_device *pdev);
+
+/**
+ * vpu_mapping_dm_addr - Mapping DTCM/DMEM to kernel virtual address
+ *
+ * @pdev:	VPU platform device
+ * @dmem_addr:	VPU's data memory address
+ *
+ * Mapping the VPU's DTCM (Data Tightly-Coupled Memory) /
+ * DMEM (Data Extended Memory) memory address to
+ * kernel virtual address.
+ *
+ * Return: Return ERR_PTR(-EINVAL) if mapping failed,
+ * otherwise the mapped kernel virtual address
+ **/
+void *vpu_mapping_dm_addr(struct platform_device *pdev,
+			  u32 dtcm_dmem_addr);
+#endif /* _MTK_VPU_H */