On Mon, May 24, 2021 at 10:47:48PM -0700, Daniele Ceraolo Spurio wrote:
> From: Vitaly Lubart <vitaly.lubart@xxxxxxxxx>
>
> Export PAVP client to work with i915 driver,
> for binding it uses kernel component framework.
>
> Signed-off-by: Vitaly Lubart <vitaly.lubart@xxxxxxxxx>
> Signed-off-by: Tomas Winkler <tomas.winkler@xxxxxxxxx>
> Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@xxxxxxxxx>
> ---
> drivers/misc/mei/Kconfig | 2 +
> drivers/misc/mei/Makefile | 1 +
> drivers/misc/mei/pxp/Kconfig | 13 ++
> drivers/misc/mei/pxp/Makefile | 7 +
> drivers/misc/mei/pxp/mei_pxp.c | 233 +++++++++++++++++++++++++++++++++
> drivers/misc/mei/pxp/mei_pxp.h | 18 +++
> 6 files changed, 274 insertions(+)
> create mode 100644 drivers/misc/mei/pxp/Kconfig
> create mode 100644 drivers/misc/mei/pxp/Makefile
> create mode 100644 drivers/misc/mei/pxp/mei_pxp.c
> create mode 100644 drivers/misc/mei/pxp/mei_pxp.h
>
> diff --git a/drivers/misc/mei/Kconfig b/drivers/misc/mei/Kconfig
> index f5fd5b786607..0e0bcd0da852 100644
> --- a/drivers/misc/mei/Kconfig
> +++ b/drivers/misc/mei/Kconfig
> @@ -47,3 +47,5 @@ config INTEL_MEI_TXE
> Intel Bay Trail
>
> source "drivers/misc/mei/hdcp/Kconfig"
> +source "drivers/misc/mei/pxp/Kconfig"
> +
> diff --git a/drivers/misc/mei/Makefile b/drivers/misc/mei/Makefile
> index f1c76f7ee804..d8e5165917f2 100644
> --- a/drivers/misc/mei/Makefile
> +++ b/drivers/misc/mei/Makefile
> @@ -26,3 +26,4 @@ mei-$(CONFIG_EVENT_TRACING) += mei-trace.o
> CFLAGS_mei-trace.o = -I$(src)
>
> obj-$(CONFIG_INTEL_MEI_HDCP) += hdcp/
> +obj-$(CONFIG_INTEL_MEI_PXP) += pxp/
> diff --git a/drivers/misc/mei/pxp/Kconfig b/drivers/misc/mei/pxp/Kconfig
> new file mode 100644
> index 000000000000..4029b96afc04
> --- /dev/null
> +++ b/drivers/misc/mei/pxp/Kconfig
> @@ -0,0 +1,13 @@
> +
> +# SPDX-License-Identifier: GPL-2.0
> +# Copyright (c) 2020, Intel Corporation. All rights reserved.
> +#
s> +config INTEL_MEI_PXP
> + tristate "Intel PXP services of ME Interface"
> + select INTEL_MEI_ME
> + depends on DRM_I915
> + help
> + MEI Support for PXP Services on Intel platforms.
> +
> + Enables the ME FW services required for PXP support through
> + I915 display driver of Intel.
> diff --git a/drivers/misc/mei/pxp/Makefile b/drivers/misc/mei/pxp/Makefile
> new file mode 100644
> index 000000000000..0329950d5794
> --- /dev/null
> +++ b/drivers/misc/mei/pxp/Makefile
> @@ -0,0 +1,7 @@
> +# SPDX-License-Identifier: GPL-2.0
> +#
> +# Copyright (c) 2020, Intel Corporation. All rights reserved.
> +#
> +# Makefile - PXP client driver for Intel MEI Bus Driver.
> +
> +obj-$(CONFIG_INTEL_MEI_PXP) += mei_pxp.o
> diff --git a/drivers/misc/mei/pxp/mei_pxp.c b/drivers/misc/mei/pxp/mei_pxp.c
> new file mode 100644
> index 000000000000..cacfbedb640a
> --- /dev/null
> +++ b/drivers/misc/mei/pxp/mei_pxp.c
> @@ -0,0 +1,233 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright © 2020 Intel Corporation
> + */
> +
> +/**
> + * DOC: MEI_PXP Client Driver
> + *
> + * The mei_pxp driver acts as a translation layer between PXP
> + * protocol implementer (I915) and ME FW by translating PXP
> + * negotiation messages to ME FW command payloads and vice versa.
> + */
> +
> +#include <linux/module.h>
> +#include <linux/slab.h>
> +#include <linux/uuid.h>
> +#include <linux/mei_cl_bus.h>
> +#include <linux/component.h>
> +#include <drm/drm_connector.h>
> +#include <drm/i915_component.h>
> +#include <drm/i915_pxp_tee_interface.h>
> +
> +#include "mei_pxp.h"
> +
> +/**
> + * mei_pxp_send_message() - Sends a PXP message to ME FW.
> + * @dev: device corresponding to the mei_cl_device
> + * @message: a message buffer to send
> + * @size: size of the message
> + * Return: 0 on Success, <0 on Failure
> + */
> +static int
> +mei_pxp_send_message(struct device *dev, const void *message, size_t size)
> +{
> + struct mei_cl_device *cldev;
> + ssize_t byte;
> +
> + if (!dev || !message)
> + return -EINVAL;
> +
> + cldev = to_mei_cl_device(dev);
> +
> + /* temporary drop const qualifier till the API is fixed */
> + byte = mei_cldev_send(cldev, (u8 *)message, size);
> + if (byte < 0) {
> + dev_dbg(dev, "mei_cldev_send failed. %zd\n", byte);
> + return byte;
> + }
> +
> + return 0;
> +}
> +
> +/**
> + * mei_pxp_receive_message() - Receives a PXP message from ME FW.
> + * @dev: device corresponding to the mei_cl_device
> + * @buffer: a message buffer to contain the received message
> + * @size: size of the buffer
> + * Return: bytes sent on Success, <0 on Failure
> + */
> +static int
> +mei_pxp_receive_message(struct device *dev, void *buffer, size_t size)
> +{
> + struct mei_cl_device *cldev;
> + ssize_t byte;
> +
> + if (!dev || !buffer)
> + return -EINVAL;
> +
> + cldev = to_mei_cl_device(dev);
> +
> + byte = mei_cldev_recv(cldev, buffer, size);
> + if (byte < 0) {
> + dev_dbg(dev, "mei_cldev_recv failed. %zd\n", byte);
> + return byte;
> + }
> +
> + return byte;
> +}
> +
> +static const struct i915_pxp_component_ops mei_pxp_ops = {
> + .owner = THIS_MODULE,
> + .send = mei_pxp_send_message,
> + .recv = mei_pxp_receive_message,
> +};
> +
> +static int mei_component_master_bind(struct device *dev)
> +{
> + struct mei_cl_device *cldev = to_mei_cl_device(dev);
> + struct i915_pxp_component *comp_master = mei_cldev_get_drvdata(cldev);
> + int ret;
> +
> + dev_dbg(dev, "%s\n", __func__);
> + comp_master->ops = &mei_pxp_ops;
> + comp_master->tee_dev = dev;
> + ret = component_bind_all(dev, comp_master);
> + if (ret < 0)
> + return ret;
> +
> + return 0;
> +}
> +
> +static void mei_component_master_unbind(struct device *dev)
> +{
> + struct mei_cl_device *cldev = to_mei_cl_device(dev);
> + struct i915_pxp_component *comp_master = mei_cldev_get_drvdata(cldev);
> +
> + dev_dbg(dev, "%s\n", __func__);
> + component_unbind_all(dev, comp_master);
> +}
> +
> +static const struct component_master_ops mei_component_master_ops = {
> + .bind = mei_component_master_bind,
> + .unbind = mei_component_master_unbind,
> +};
> +
> +/**
> + * mei_pxp_component_match - compare function for matching mei pxp.
> + *
> + * The function checks if the driver is i915, the subcomponent is PXP
> + * and the grand parent of pxp and the parent of i915 are the same
> + * PCH device.
> + *
> + * @dev: master device
> + * @subcomponent: subcomponent to match (I915_COMPONENT_PXP)
> + * @data: compare data (mei pxp device)
> + *
> + * Return:
> + * * 1 - if components match
> + * * 0 - otherwise
> + */
> +static int mei_pxp_component_match(struct device *dev, int subcomponent,
> + void *data)
> +{
> + struct device *base = data;
> +
> + if (subcomponent != I915_COMPONENT_PXP)
> + return 0;
> +
> + if (strcmp(dev->driver->name, "i915") == 0) {
> + base = base->parent;
> + if (!base)
> + return 0;
> +
> + base = base->parent;
> + dev = dev->parent;
> + return (base && dev && dev == base);
> + }
> +
> + return 0;
> +}
> +
> +static int mei_pxp_probe(struct mei_cl_device *cldev,
> + const struct mei_cl_device_id *id)
> +{
> + struct i915_pxp_component *comp_master;
> + struct component_match *master_match;
> + int ret;
> +
> + ret = mei_cldev_enable(cldev);
> + if (ret < 0) {
> + dev_err(&cldev->dev, "mei_cldev_enable Failed. %d\n", ret);
> + goto enable_err_exit;
> + }
> +
> + comp_master = kzalloc(sizeof(*comp_master), GFP_KERNEL);
> + if (!comp_master) {
> + ret = -ENOMEM;
> + goto err_exit;
> + }
> +
> + master_match = NULL;
> + component_match_add_typed(&cldev->dev, &master_match,
> + mei_pxp_component_match, &cldev->dev);
> + if (IS_ERR_OR_NULL(master_match)) {
> + ret = -ENOMEM;
> + goto err_exit;
> + }
> +
> + mei_cldev_set_drvdata(cldev, comp_master);
> + ret = component_master_add_with_match(&cldev->dev,
> + &mei_component_master_ops,
> + master_match);
> + if (ret < 0) {
> + dev_err(&cldev->dev, "Master comp add failed %d\n", ret);
> + goto err_exit;
> + }
> +
> + return 0;
> +
> +err_exit:
> + mei_cldev_set_drvdata(cldev, NULL);
> + kfree(comp_master);
> + mei_cldev_disable(cldev);
> +enable_err_exit:
> + return ret;
> +}
> +
> +static void mei_pxp_remove(struct mei_cl_device *cldev)
> +{
> + struct i915_pxp_component *comp_master = mei_cldev_get_drvdata(cldev);
> + int ret;
> +
> + component_master_del(&cldev->dev, &mei_component_master_ops);
> + kfree(comp_master);
> + mei_cldev_set_drvdata(cldev, NULL);
> +
> + ret = mei_cldev_disable(cldev);
> + if (ret)
> + dev_warn(&cldev->dev, "mei_cldev_disable() failed\n");
> +}
> +
> +/* fbf6fcf1-96cf-4e2e-a6a6-1bab8cbe36b1 : PAVP GUID*/
^ missing space
> +#define MEI_GUID_PXP GUID_INIT(0xfbf6fcf1, 0x96cf, 0x4e2e, 0xA6, \
> + 0xa6, 0x1b, 0xab, 0x8c, 0xbe, 0x36, 0xb1)
I don't have the spec to confirm this... that said...
the implementation looks clean and with the very little that I learned
from MEI on the recent months I'm comfortable in adding:
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@xxxxxxxxx>
Tomas, ack to get it from drm/drm-intel tree?
> +
> +static struct mei_cl_device_id mei_pxp_tbl[] = {
> + { .uuid = MEI_GUID_PXP, .version = MEI_CL_VERSION_ANY },
> + { }
> +};
> +MODULE_DEVICE_TABLE(mei, mei_pxp_tbl);
> +
> +static struct mei_cl_driver mei_pxp_driver = {
> + .id_table = mei_pxp_tbl,
> + .name = KBUILD_MODNAME,
> + .probe = mei_pxp_probe,
> + .remove = mei_pxp_remove,
> +};
> +
> +module_mei_cl_driver(mei_pxp_driver);
> +
> +MODULE_AUTHOR("Intel Corporation");
> +MODULE_LICENSE("GPL");
> +MODULE_DESCRIPTION("MEI PXP");
> diff --git a/drivers/misc/mei/pxp/mei_pxp.h b/drivers/misc/mei/pxp/mei_pxp.h
> new file mode 100644
> index 000000000000..e7b15373fefd
> --- /dev/null
> +++ b/drivers/misc/mei/pxp/mei_pxp.h
> @@ -0,0 +1,18 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/*
> + * Copyright © 2020 Intel Corporation
> + *
> + * Authors:
> + * Vitaly Lubart <vitaly.lubart@xxxxxxxxx>
> + */
> +
> +#ifndef __MEI_PXP_H__
> +#define __MEI_PXP_H__
> +
> +/* me_pxp_status: Enumeration of all PXP Status Codes */
> +enum me_pxp_status {
> + ME_PXP_STATUS_SUCCESS = 0x0000,
> +
> +};
> +
> +#endif /* __MEI_PXP_H__ */
> --
> 2.29.2
>
