[PATCH v2 02/10] mei: late_bind: add late binding component driver

Nilawar, Badal badal.nilawar at intel.com
Mon Jun 16 15:13:25 UTC 2025


On 14-06-2025 13:32, Gupta, Anshuman wrote:
>
>> -----Original Message-----
>> From: Nilawar, Badal<badal.nilawar at intel.com>
>> Sent: Friday, June 6, 2025 11:27 PM
>> To:intel-xe at lists.freedesktop.org;dri-devel at lists.freedesktop.org
>> Cc: Gupta, Anshuman<anshuman.gupta at intel.com>; Vivi, Rodrigo
>> <rodrigo.vivi at intel.com>; Usyskin, Alexander<alexander.usyskin at intel.com>;
>> gregkh at linuxfoundation.org; Ceraolo Spurio, Daniele
>> <daniele.ceraolospurio at intel.com>;jgg at nvidia.com
>> Subject: [PATCH v2 02/10] mei: late_bind: add late binding component driver
>>
>> From: Alexander Usyskin<alexander.usyskin at intel.com>
>>
>> Add late binding component driver.
>> It allows pushing the late binding configuration from, for example, the Xe
>> graphics driver to the Intel discrete graphics card's CSE device.
>>
>> Signed-off-by: Alexander Usyskin<alexander.usyskin at intel.com>
>> Signed-off-by: Badal Nilawar<badal.nilawar at intel.com>
>> ---
>> v2:
>>   - Use generic naming (Jani)
>>   - Drop xe_late_bind_component struct to move to xe code (Daniele/Sasha)
>> ---
>>   drivers/misc/mei/Kconfig                    |   1 +
>>   drivers/misc/mei/Makefile                   |   1 +
>>   drivers/misc/mei/late_bind/Kconfig          |  12 +
>>   drivers/misc/mei/late_bind/Makefile         |   9 +
>>   drivers/misc/mei/late_bind/mei_late_bind.c  | 261 ++++++++++++++++++++
>>   include/drm/intel/i915_component.h          |   1 +
>>   include/drm/intel/late_bind_mei_interface.h |  37 +++
>>   7 files changed, 322 insertions(+)
>>   create mode 100644 drivers/misc/mei/late_bind/Kconfig
>>   create mode 100644 drivers/misc/mei/late_bind/Makefile
>>   create mode 100644 drivers/misc/mei/late_bind/mei_late_bind.c
>>   create mode 100644 include/drm/intel/late_bind_mei_interface.h
>>
>> diff --git a/drivers/misc/mei/Kconfig b/drivers/misc/mei/Kconfig index
>> 7575fee96cc6..771becc68095 100644
>> --- a/drivers/misc/mei/Kconfig
>> +++ b/drivers/misc/mei/Kconfig
>> @@ -84,5 +84,6 @@ config INTEL_MEI_VSC
>>   source "drivers/misc/mei/hdcp/Kconfig"
>>   source "drivers/misc/mei/pxp/Kconfig"
>>   source "drivers/misc/mei/gsc_proxy/Kconfig"
>> +source "drivers/misc/mei/late_bind/Kconfig"
>>
>>   endif
>> diff --git a/drivers/misc/mei/Makefile b/drivers/misc/mei/Makefile index
>> 6f9fdbf1a495..84bfde888d81 100644
>> --- a/drivers/misc/mei/Makefile
>> +++ b/drivers/misc/mei/Makefile
>> @@ -31,6 +31,7 @@ CFLAGS_mei-trace.o = -I$(src)
>>   obj-$(CONFIG_INTEL_MEI_HDCP) += hdcp/
>>   obj-$(CONFIG_INTEL_MEI_PXP) += pxp/
>>   obj-$(CONFIG_INTEL_MEI_GSC_PROXY) += gsc_proxy/
>> +obj-$(CONFIG_INTEL_MEI_LATE_BIND) += late_bind/
>>
>>   obj-$(CONFIG_INTEL_MEI_VSC_HW) += mei-vsc-hw.o  mei-vsc-hw-y := vsc-
>> tp.o diff --git a/drivers/misc/mei/late_bind/Kconfig
>> b/drivers/misc/mei/late_bind/Kconfig
>> new file mode 100644
>> index 000000000000..c5302303e5af
>> --- /dev/null
>> +++ b/drivers/misc/mei/late_bind/Kconfig
>> @@ -0,0 +1,12 @@
>> +# SPDX-License-Identifier: GPL-2.0
>> +# Copyright (c) 2025, Intel Corporation. All rights reserved.
>> +#
>> +config INTEL_MEI_LATE_BIND
>> +	tristate "Intel late binding support on ME Interface"
>> +	select INTEL_MEI_ME
>> +	depends on DRM_XE
>> +	help
>> +	  MEI Support for Late Binding for Intel graphics card.
>> +
>> +	  Enables the ME FW interfaces for Late Binding for
>> +          Xe display driver of Intel.
> It is needed even for headless cards as well.
Will change the description.
>> diff --git a/drivers/misc/mei/late_bind/Makefile
>> b/drivers/misc/mei/late_bind/Makefile
>> new file mode 100644
>> index 000000000000..a0aeda5853f0
>> --- /dev/null
>> +++ b/drivers/misc/mei/late_bind/Makefile
>> @@ -0,0 +1,9 @@
>> +# SPDX-License-Identifier: GPL-2.0
>> +#
>> +# Copyright (c) 2025, Intel Corporation. All rights reserved.
>> +#
>> +# Makefile - Late Binding client driver for Intel MEI Bus Driver.
>> +
>> +subdir-ccflags-y += -I$(srctree)/drivers/misc/mei/
>> +
>> +obj-$(CONFIG_INTEL_MEI_LATE_BIND) += mei_late_bind.o
>> diff --git a/drivers/misc/mei/late_bind/mei_late_bind.c
>> b/drivers/misc/mei/late_bind/mei_late_bind.c
>> new file mode 100644
>> index 000000000000..964757a9b33a
>> --- /dev/null
>> +++ b/drivers/misc/mei/late_bind/mei_late_bind.c
>> @@ -0,0 +1,261 @@
>> +// SPDX-License-Identifier: GPL-2.0
>> +/*
>> + * Copyright (C) 2025 Intel Corporation  */ #include
>> +<drm/drm_connector.h> #include <drm/intel/i915_component.h> #include
> Why do we need drm_connector header ?
> Remove unnecessary headers.
Sure
>> +<drm/intel/late_bind_mei_interface.h>
>> +#include <linux/component.h>
>> +#include <linux/pci.h>
>> +#include <linux/mei_cl_bus.h>
>> +#include <linux/module.h>
>> +#include <linux/overflow.h>
>> +#include <linux/slab.h>
>> +#include <linux/uuid.h>
>> +
>> +#include "mkhi.h"
>> +
>> +#define GFX_SRV_MKHI_LATE_BINDING_CMD 0x12 #define
> Why it is not prefixed with DGFX. This is unique to DGFX cards ?
> @alexander any comment on above ?
>> +GFX_SRV_MKHI_LATE_BINDING_RSP (GFX_SRV_MKHI_LATE_BINDING_CMD
>> | 0x80)
>> +
>> +#define LATE_BIND_SEND_TIMEOUT_MSEC 3000 #define
>> +LATE_BIND_RECV_TIMEOUT_MSEC 3000
>  From where we got these delay numbers, from any specs or it is arbitrary delay specific to let bind ?
> Add a code comment in that case.
>> +
>> +/**
>> + * struct csc_heci_late_bind_req - late binding request
>> + * @header: @ref mkhi_msg_hdr
>> + * @type: type of the late binding payload
>> + * @flags: flags to be passed to the firmware
>> + * @reserved: reserved field
>> + * @payload_size: size of the payload data in bytes
>> + * @payload: data to be sent to the firmware  */ struct
>> +csc_heci_late_bind_req {
>> +	struct mkhi_msg_hdr header;
>> +	u32 type;
>> +	u32 flags;
>> +	u32 reserved[2];
>> +	u32 payload_size;
>> +	u8  payload[] __counted_by(payload_size); } __packed;
>> +
>> +/**
>> + * struct csc_heci_late_bind_rsp - late binding response
>> + * @header: @ref mkhi_msg_hdr
>> + * @type: type of the late binding payload
>> + * @reserved: reserved field
>> + * @status: status of the late binding command execution by firmware
>> +*/ struct csc_heci_late_bind_rsp {
>> +	struct mkhi_msg_hdr header;
>> +	u32 type;
>> +	u32 reserved[2];
>> +	u32 status;
>> +} __packed;
>> +
>> +static int mei_late_bind_check_response(const struct device *dev, const
>> +struct mkhi_msg_hdr *hdr) {
>> +	if (hdr->group_id != MKHI_GROUP_ID_GFX) {
>> +		dev_err(dev, "Mismatch group id: 0x%x instead of 0x%x\n",
>> +			hdr->group_id, MKHI_GROUP_ID_GFX);
>> +		return -EINVAL;
>> +	}
>> +
>> +	if (hdr->command != GFX_SRV_MKHI_LATE_BINDING_RSP) {
>> +		dev_err(dev, "Mismatch command: 0x%x instead of 0x%x\n",
>> +			hdr->command,
>> GFX_SRV_MKHI_LATE_BINDING_RSP);
>> +		return -EINVAL;
>> +	}
>> +
>> +	return 0;
>> +}
>> +
>> +/**
>> + * mei_late_bind_push_config - Sends a config to the firmware.
>> + * @dev: device struct corresponding to the mei device
>> + * @type: payload type
>> + * @flags: payload flags
>> + * @payload: payload buffer
>> + * @payload_size: payload buffer size
>> + *
>> + * Return: 0 success, negative errno value on transport failure,
>> + *         positive status returned by FW
>> + */
>> +static int mei_late_bind_push_config(struct device *dev, u32 type, u32 flags,
>> +				     const void *payload, size_t payload_size) {
>> +	struct mei_cl_device *cldev;
>> +	struct csc_heci_late_bind_req *req = NULL;
>> +	struct csc_heci_late_bind_rsp rsp;
>> +	size_t req_size;
>> +	int ret;
>> +
>> +	if (!dev || !payload || !payload_size)
>> +		return -EINVAL;
>> +
>> +	cldev = to_mei_cl_device(dev);
>> +
>> +	ret = mei_cldev_enable(cldev);
>> +	if (ret < 0) {
>> +		dev_dbg(dev, "mei_cldev_enable failed. %d\n", ret);
>> +		return ret;
>> +	}
>> +
>> +	req_size = struct_size(req, payload, payload_size);
>> +	if (req_size > mei_cldev_mtu(cldev)) {
>> +		dev_err(dev, "Payload is too big %zu\n", payload_size);
>> +		ret = -EMSGSIZE;
>> +		goto end;
>> +	}
>> +
>> +	req = kmalloc(req_size, GFP_KERNEL);
>> +	if (!req) {
>> +		ret = -ENOMEM;
>> +		goto end;
>> +	}
>> +
>> +	req->header.group_id = MKHI_GROUP_ID_GFX;
>> +	req->header.command = GFX_SRV_MKHI_LATE_BINDING_CMD;
>> +	req->type = type;
>> +	req->flags = flags;
>> +	req->reserved[0] = 0;
>> +	req->reserved[1] = 0;
>> +	req->payload_size = payload_size;
>> +	memcpy(req->payload, payload, payload_size);
>> +
>> +	ret = mei_cldev_send_timeout(cldev, (void *)req, req_size,
>> LATE_BIND_SEND_TIMEOUT_MSEC);
>> +	if (ret < 0) {
>> +		dev_err(dev, "mei_cldev_send failed. %d\n", ret);
>> +		goto end;
>> +	}
>> +	ret = mei_cldev_recv_timeout(cldev, (void *)&rsp, sizeof(rsp),
>> LATE_BIND_RECV_TIMEOUT_MSEC);
>> +	if (ret < 0) {
>> +		dev_err(dev, "mei_cldev_recv failed. %d\n", ret);
>> +		goto end;
>> +	}
>> +	ret = mei_late_bind_check_response(dev, &rsp.header);
>> +	if (ret) {
>> +		dev_err(dev, "bad result response from the firmware:
>> 0x%x\n",
>> +			*(uint32_t *)&rsp.header);
>> +		goto end;
>> +	}
>> +	ret = (int)rsp.status;
>> +	dev_dbg(dev, "mei_late_bind_push_config status = %d\n", ret);
>> +
>> +end:
>> +	mei_cldev_disable(cldev);
>> +	kfree(req);
>> +	return ret;
>> +}
>> +
>> +static const struct late_bind_component_ops mei_late_bind_ops = {
>> +	.owner = THIS_MODULE,
>> +	.push_config = mei_late_bind_push_config, };
>> +
>> +static int mei_component_master_bind(struct device *dev) {
>> +	return component_bind_all(dev, (void *)&mei_late_bind_ops); }
>> +
>> +static void mei_component_master_unbind(struct device *dev) {
>> +	component_unbind_all(dev, (void *)&mei_late_bind_ops); }
>> +
>> +static const struct component_master_ops mei_component_master_ops = {
>> +	.bind = mei_component_master_bind,
>> +	.unbind = mei_component_master_unbind, };
>> +
>> +/**
>> + * mei_late_bind_component_match - compare function for matching mei
>> late bind.
>> + *
>> + *    The function checks if requested is Intel VGA device
>> + *    and the parent of requester and the grand parent of mei_if are the same
>> + *    device.
> This might be broken for headless card, headless care need to necessarily be VGA card.
Will do %s/PCI_CLASS_DISPLAY_VGA/PCI_CLASS_DISPLAY to cover headless cards.
>> + *
>> + * @dev: master device
>> + * @subcomponent: subcomponent to match
>> (I915_COMPONENT_LATE_BIND)
>> + * @data: compare data (mei late-bind bus device)
>> + *
>> + * Return:
>> + * * 1 - if components match
>> + * * 0 - otherwise
>> + */
>> +static int mei_late_bind_component_match(struct device *dev, int
>> subcomponent,
>> +					 void *data)
>> +{
>> +	struct device *base = data;
>> +	struct pci_dev *pdev;
>> +
>> +	if (!dev)
>> +		return 0;
>> +
>> +	if (!dev_is_pci(dev))
>> +		return 0;
>> +
>> +	pdev = to_pci_dev(dev);
>> +
>> +	if (pdev->class != (PCI_CLASS_DISPLAY_VGA << 8) ||
>> +	    pdev->vendor != PCI_VENDOR_ID_INTEL)
>> +		return 0;
>> +
>> +	if (subcomponent != I915_COMPONENT_LATE_BIND)
>> +		return 0;
> Why I915_COMPONENT_LATE_BIND ?
> Isn't this should be XE_ COMPONENT_LATE_BIND.

Suggestion is not to use XE_ prefix in generic code. I915_ prefix is due 
to historical reasons, its being used for other components as well which 
are common in i915/xe. |
If everyone agree then I will use INTEL_ prefix here.

>> +
>> +	base = base->parent;
>> +	if (!base) /* mei device */
>> +		return 0;
>> +
>> +	base = base->parent; /* pci device */
> Is it sgunit pci endpoint ?
> If yes then good to mention in comment.
>> +
>> +	return !!base && dev == base;
>> +}
>> +
>> +static int mei_late_bind_probe(struct mei_cl_device *cldev,
>> +			       const struct mei_cl_device_id *id) {
>> +	struct component_match *master_match = NULL;
>> +	int ret;
>> +
>> +	component_match_add_typed(&cldev->dev, &master_match,
>> +				  mei_late_bind_component_match, &cldev-
>>> dev);
>> +	if (IS_ERR_OR_NULL(master_match))
>> +		return -ENOMEM;
>> +
>> +	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);
>> +
>> +	return ret;
>> +}
>> +
>> +static void mei_late_bind_remove(struct mei_cl_device *cldev) {
>> +	component_master_del(&cldev->dev,
>> &mei_component_master_ops); }
>> +
>> +#define MEI_GUID_MKHI UUID_LE(0xe2c2afa2, 0x3817, 0x4d19, \
>> +			      0x9d, 0x95, 0x6, 0xb1, 0x6b, 0x58, 0x8a, 0x5d)
>> +
>> +static struct mei_cl_device_id mei_late_bind_tbl[] = {
>> +	{ .uuid = MEI_GUID_MKHI, .version = MEI_CL_VERSION_ANY },
>> +	{ }
>> +};
>> +MODULE_DEVICE_TABLE(mei, mei_late_bind_tbl);
>> +
>> +static struct mei_cl_driver mei_late_bind_driver = {
>> +	.id_table = mei_late_bind_tbl,
>> +	.name = KBUILD_MODNAME,
>> +	.probe = mei_late_bind_probe,
>> +	.remove	= mei_late_bind_remove,
>> +};
>> +
>> +module_mei_cl_driver(mei_late_bind_driver);
>> +
>> +MODULE_AUTHOR("Intel Corporation");
>> +MODULE_LICENSE("GPL");
>> +MODULE_DESCRIPTION("MEI Late Binding");
>> diff --git a/include/drm/intel/i915_component.h
>> b/include/drm/intel/i915_component.h
>> index 4ea3b17aa143..4945044d41e6 100644
>> --- a/include/drm/intel/i915_component.h
>> +++ b/include/drm/intel/i915_component.h
>> @@ -31,6 +31,7 @@ enum i915_component_type {
>>   	I915_COMPONENT_HDCP,
>>   	I915_COMPONENT_PXP,
>>   	I915_COMPONENT_GSC_PROXY,
>> +	I915_COMPONENT_LATE_BIND,
> We probably need a change here to make a xe specific component.

Yes as mentioned in response of previous comment this can be 
INTEL_COMPONENT_LATE_BIND if everyone agree.

Regards,
Badal

>
> Thanks,
> Anshuman Gupta.
>>   };
>>
>>   /* MAX_PORT is the number of port
>> diff --git a/include/drm/intel/late_bind_mei_interface.h
>> b/include/drm/intel/late_bind_mei_interface.h
>> new file mode 100644
>> index 000000000000..6b54b8cec5ae
>> --- /dev/null
>> +++ b/include/drm/intel/late_bind_mei_interface.h	
>> @@ -0,0 +1,37 @@
>> +/* SPDX-License-Identifier: MIT */
>> +/*
>> + * Copyright (c) 2025 Intel Corporation  */
>> +
>> +#ifndef _LATE_BIND_MEI_INTERFACE_H_
>> +#define _LATE_BIND_MEI_INTERFACE_H_
>> +
>> +#include <linux/types.h>
>> +
>> +struct device;
>> +struct module;
>> +
>> +/**
>> + * struct late_bind_component_ops - ops for Late Binding services.
>> + * @owner: Module providing the ops
>> + * @push_config: Sends a config to FW.
>> + */
>> +struct late_bind_component_ops {
>> +	struct module *owner;
>> +
>> +	/**
>> +	 * @push_config: Sends a config to FW.
>> +	 * @dev: device struct corresponding to the mei device
>> +	 * @type: payload type
>> +	 * @flags: payload flags
>> +	 * @payload: payload buffer
>> +	 * @payload_size: payload buffer size
>> +	 *
>> +	 * Return: 0 success, negative errno value on transport failure,
>> +	 *         positive status returned by FW
>> +	 */
>> +	int (*push_config)(struct device *dev, u32 type, u32 flags,
>> +			   const void *payload, size_t payload_size); };
>> +
>> +#endif /* _LATE_BIND_MEI_INTERFACE_H_ */
>> --
>> 2.34.1
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.freedesktop.org/archives/intel-xe/attachments/20250616/4bd81645/attachment-0001.htm>


More information about the Intel-xe mailing list