diff mbox series

[RFC,v7,12/12] memory: RAS2: Add memory RAS2 driver

Message ID 20240223143723.1574-13-shiju.jose@huawei.com (mailing list archive)
State RFC, archived
Headers show
Series memory: scrub: introduce subsystem + CXL/ACPI-RAS2 drivers | expand

Commit Message

Shiju Jose Feb. 23, 2024, 2:37 p.m. UTC
From: Shiju Jose <shiju.jose@huawei.com>

Memory RAS2 driver binds to the platform device add by the ACPI RAS2
driver.
Driver registers the PCC channel for communicating with the ACPI compliant
platform that contains RAS2 command support in the hardware.

Add interface functions to support configuring the parameters of HW patrol
scrubs in the system, which exposed to the kernel via the RAS2 and PCC,
using the RAS2 commands.

Add support for RAS2 platform devices to register with scrub subsystem
driver. This enables user to configure the parameters of HW patrol scrubs,
which exposed to the kernel via the RAS2 table, through the scrub sysfs
attributes.

Open Question:
Sysfs scrub control attribute "enable_background_scrub" is added for RAS2,
based on the feedback from Bill Schwartz <wschwartz@amperecomputing.com
on v4 to enable/disable the background_scrubbing in the platform as defined in the
“Configure Scrub Parameters [INPUT]“ field  in RAS2 Table 5.87: Parameter Block
Structure for PATROL_SCRUB.
Is it a right approach to support "enable_background_scrub" in the sysfs
scrub control?

Signed-off-by: Shiju Jose <shiju.jose@huawei.com>
---
 drivers/memory/Kconfig       |  14 ++
 drivers/memory/Makefile      |   2 +
 drivers/memory/ras2.c        | 364 +++++++++++++++++++++++++++++++++++
 drivers/memory/ras2_common.c | 282 +++++++++++++++++++++++++++
 include/memory/ras2.h        |  88 +++++++++
 5 files changed, 750 insertions(+)
 create mode 100644 drivers/memory/ras2.c
 create mode 100644 drivers/memory/ras2_common.c
 create mode 100755 include/memory/ras2.h

Comments

Yazen Ghannam March 28, 2024, 3:23 p.m. UTC | #1
On 2/23/2024 9:37 AM, shiju.jose@huawei.com wrote:
> From: Shiju Jose <shiju.jose@huawei.com>
> 
> Memory RAS2 driver binds to the platform device add by the ACPI RAS2
> driver.
> Driver registers the PCC channel for communicating with the ACPI compliant
> platform that contains RAS2 command support in the hardware.
> 
> Add interface functions to support configuring the parameters of HW patrol
> scrubs in the system, which exposed to the kernel via the RAS2 and PCC,
> using the RAS2 commands.
> 
> Add support for RAS2 platform devices to register with scrub subsystem
> driver. This enables user to configure the parameters of HW patrol scrubs,
> which exposed to the kernel via the RAS2 table, through the scrub sysfs
> attributes.
> 
> Open Question:
> Sysfs scrub control attribute "enable_background_scrub" is added for RAS2,
> based on the feedback from Bill Schwartz <wschwartz@amperecomputing.com
> on v4 to enable/disable the background_scrubbing in the platform as defined in the
> “Configure Scrub Parameters [INPUT]“ field  in RAS2 Table 5.87: Parameter Block
> Structure for PATROL_SCRUB.
> Is it a right approach to support "enable_background_scrub" in the sysfs
> scrub control?
> 
> Signed-off-by: Shiju Jose <shiju.jose@huawei.com>
> ---
>  drivers/memory/Kconfig       |  14 ++
>  drivers/memory/Makefile      |   2 +
>  drivers/memory/ras2.c        | 364 +++++++++++++++++++++++++++++++++++
>  drivers/memory/ras2_common.c | 282 +++++++++++++++++++++++++++
>  include/memory/ras2.h        |  88 +++++++++
>  5 files changed, 750 insertions(+)
>  create mode 100644 drivers/memory/ras2.c
>  create mode 100644 drivers/memory/ras2_common.c
>  create mode 100755 include/memory/ras2.h
> 

Sorry if this was already covered, but why not put the common scrub and ras2
changes under /drivers/ras/?

Thanks,
Yazen
Daniel Ferguson March 28, 2024, 11:41 p.m. UTC | #2
> +/*
> + * The below functions are exposed to OSPM, to query, configure and
> + * initiate memory patrol scrub.
> + */
> +static int ras2_is_patrol_scrub_support(struct ras2_context *ras2_ctx)
> +{
> +	int ret;
> +	struct acpi_ras2_shared_memory  __iomem *generic_comm_base;
> +
> +	if (!ras2_ctx || !ras2_ctx->pcc_comm_addr)
> +		return -EFAULT;
> +
> +	generic_comm_base = ras2_ctx->pcc_comm_addr;
> +	guard(spinlock_irqsave)(&ras2_ctx->spinlock);
> +	generic_comm_base->set_capabilities[0] = 0;
> +
> +	/* send command for reading RAS2 capabilities */
> +	ret = ras2_send_pcc_cmd(ras2_ctx, RAS2_PCC_CMD_EXEC);
> +	if (ret) {
> +		dev_err(ras2_ctx->dev,
> +			"%s: ras2_send_pcc_cmd failed\n", __func__);
> +		return ret;
> +	}
> +
> +	return generic_comm_base->features[0] & RAS2_SUPPORT_HW_PARTOL_SCRUB;

Since firmware populates the feature bitmask on initialization, it would 
seem
that we do not need to send a PCC CMD EXEC to read RAS2 capabilities.
> +}
> +
> +static int ras2_get_patrol_scrub_params(struct ras2_context *ras2_ctx,
> +					struct ras2_scrub_params *params)
> +{
> +	int ret = 0;
> +	u8  min_supp_scrub_rate, max_supp_scrub_rate;
> +	struct acpi_ras2_shared_memory  __iomem *generic_comm_base;
> +	struct acpi_ras2_patrol_scrub_parameter __iomem *patrol_scrub_params;
> +
> +	if (!ras2_ctx || !ras2_ctx->pcc_comm_addr)
> +		return -EFAULT;
> +
> +	generic_comm_base = ras2_ctx->pcc_comm_addr;
> +	patrol_scrub_params = ras2_ctx->pcc_comm_addr + sizeof(*generic_comm_base);
> +
> +	guard(spinlock_irqsave)(&ras2_ctx->spinlock);
> +	generic_comm_base->set_capabilities[0] = RAS2_SUPPORT_HW_PARTOL_SCRUB;
> +	/* send command for reading RAS2 capabilities */
> +	ret = ras2_send_pcc_cmd(ras2_ctx, RAS2_PCC_CMD_EXEC);
> +	if (ret) {
> +		dev_err(ras2_ctx->dev,
> +			"%s: ras2_send_pcc_cmd failed\n", __func__);
> +		return ret;
> +	}

Similarly, since firmware populates the feature bitmask on
initialization, it would seem that we do not need to send
a PCC CMD EXEC to read RAS2 capabilities.
> +
> +	if (!(generic_comm_base->features[0] & RAS2_SUPPORT_HW_PARTOL_SCRUB) ||
> +	    !(generic_comm_base->num_parameter_blocks)) {
> +		dev_err(ras2_ctx->dev,
> +			"%s: Platform does not support HW Patrol Scrubber\n", __func__);
> +		return -EOPNOTSUPP;
> +	}
> +
> +	if (!patrol_scrub_params->requested_address_range[1]) {
> +		dev_err(ras2_ctx->dev,
> +			"%s: Invalid requested address range, \
> +			requested_address_range[0]=0x%llx \
> +			requested_address_range[1]=0x%llx\n",
> +			__func__,
> +			patrol_scrub_params->requested_address_range[0],
> +			patrol_scrub_params->requested_address_range[1]);
> +		return -EOPNOTSUPP;
> +	}
> +
> +	generic_comm_base->set_capabilities[0] = RAS2_SUPPORT_HW_PARTOL_SCRUB;
> +	patrol_scrub_params->header.type = RAS2_TYPE_PATROL_SCRUB;

header.type should already be populated by firmware. Is assigning it
here necessary?
> +	patrol_scrub_params->patrol_scrub_command = RAS2_GET_PATROL_PARAMETERS;
> +
> +	/* send command for reading the HW patrol scrub parameters */
> +	ret = ras2_send_pcc_cmd(ras2_ctx, RAS2_PCC_CMD_EXEC);
> +	if (ret) {
> +		dev_err(ras2_ctx->dev,
> +			"%s: failed to read HW patrol scrub parameters\n",
> +			__func__);
> +		return ret;
> +	}
> +
> +	/* copy output scrub parameters */
> +	params->addr_base = patrol_scrub_params->actual_address_range[0];
> +	params->addr_size = patrol_scrub_params->actual_address_range[1];
> +	params->flags = patrol_scrub_params->flags;
> +	params->rate = FIELD_GET(RAS2_PATROL_SCRUB_RATE_OUT_MASK,
> +				 patrol_scrub_params->scrub_params_out);
> +	min_supp_scrub_rate = FIELD_GET(RAS2_PATROL_SCRUB_MIN_RATE_OUT_MASK,
> +					patrol_scrub_params->scrub_params_out);
> +	max_supp_scrub_rate = FIELD_GET(RAS2_PATROL_SCRUB_MAX_RATE_OUT_MASK,
> +					patrol_scrub_params->scrub_params_out);
> +	snprintf(params->rate_avail, RAS2_MAX_RATE_RANGE_LENGTH,
> +		 "%d-%d", min_supp_scrub_rate, max_supp_scrub_rate);
> +
> +	return 0;
> +}
> +
> +static int ras2_enable_patrol_scrub(struct ras2_context *ras2_ctx, bool enable)
> +{
> +	int ret = 0;
> +	struct ras2_scrub_params params;
> +	struct acpi_ras2_shared_memory  __iomem *generic_comm_base;
> +	u8 scrub_rate_to_set, min_supp_scrub_rate, max_supp_scrub_rate;
> +	struct acpi_ras2_patrol_scrub_parameter __iomem *patrol_scrub_params;
> +
> +	if (!ras2_ctx || !ras2_ctx->pcc_comm_addr)
> +		return -EFAULT;
> +
> +	generic_comm_base = ras2_ctx->pcc_comm_addr;
> +	patrol_scrub_params = ras2_ctx->pcc_comm_addr + sizeof(*generic_comm_base);
> +
> +	if (enable) {
> +		ret = ras2_get_patrol_scrub_params(ras2_ctx, &params);
> +		if (ret)
> +			return ret;
> +	}
> +
> +	guard(spinlock_irqsave)(&ras2_ctx->spinlock);
> +	generic_comm_base->set_capabilities[0] = RAS2_SUPPORT_HW_PARTOL_SCRUB;
> +	patrol_scrub_params->header.type = RAS2_TYPE_PATROL_SCRUB;

header.type should already be populated by firmware. Is assigning it
here necessary?
> +
> +	if (enable) {
> +		patrol_scrub_params->patrol_scrub_command = RAS2_START_PATROL_SCRUBBER;
> +		patrol_scrub_params->requested_address_range[0] = params.addr_base;
> +		patrol_scrub_params->requested_address_range[1] = params.addr_size;
> +
> +		scrub_rate_to_set = FIELD_GET(RAS2_PATROL_SCRUB_RATE_IN_MASK,
> +					      patrol_scrub_params->scrub_params_in);
> +		min_supp_scrub_rate = FIELD_GET(RAS2_PATROL_SCRUB_MIN_RATE_OUT_MASK,
> +						patrol_scrub_params->scrub_params_out);
> +		max_supp_scrub_rate = FIELD_GET(RAS2_PATROL_SCRUB_MAX_RATE_OUT_MASK,
> +						patrol_scrub_params->scrub_params_out);
> +		if (scrub_rate_to_set < min_supp_scrub_rate ||
> +		    scrub_rate_to_set > max_supp_scrub_rate) {
> +			dev_warn(ras2_ctx->dev,
> +				 "patrol scrub rate to set is out of the supported range\n");
> +			dev_warn(ras2_ctx->dev,
> +				 "min_supp_scrub_rate=%d max_supp_scrub_rate=%d\n",
> +				 min_supp_scrub_rate, max_supp_scrub_rate);
> +			return -EINVAL;
> +		}
> +	} else {
> +		patrol_scrub_params->patrol_scrub_command = RAS2_STOP_PATROL_SCRUBBER;
> +	}
> +
> +	/* send command for enable/disable HW patrol scrub */
> +	ret = ras2_send_pcc_cmd(ras2_ctx, RAS2_PCC_CMD_EXEC);
> +	if (ret) {
> +		pr_err("%s: failed to enable/disable the HW patrol scrub\n", __func__);
> +		return ret;
> +	}
> +
> +	return 0;
> +}
> +
> +static int ras2_enable_background_scrub(struct ras2_context *ras2_ctx, bool enable)
> +{
> +	int ret;
> +	struct acpi_ras2_shared_memory  __iomem *generic_comm_base;
> +	struct acpi_ras2_patrol_scrub_parameter __iomem *patrol_scrub_params;
> +
> +	if (!ras2_ctx || !ras2_ctx->pcc_comm_addr)
> +		return -EFAULT;
> +
> +	generic_comm_base = ras2_ctx->pcc_comm_addr;
> +	patrol_scrub_params = ras2_ctx->pcc_comm_addr + sizeof(*generic_comm_base);
> +
> +	guard(spinlock_irqsave)(&ras2_ctx->spinlock);
> +	generic_comm_base->set_capabilities[0] = RAS2_SUPPORT_HW_PARTOL_SCRUB;
> +	patrol_scrub_params->header.type = RAS2_TYPE_PATROL_SCRUB;

header.type should already be populated by firmware. Is assigning it
here necessary?
> +	patrol_scrub_params->patrol_scrub_command = RAS2_START_PATROL_SCRUBBER;
> +
> +	patrol_scrub_params->scrub_params_in &= ~RAS2_PATROL_SCRUB_EN_BACKGROUND;
> +	patrol_scrub_params->scrub_params_in |= FIELD_PREP(RAS2_PATROL_SCRUB_EN_BACKGROUND,
> +							   enable);
> +
> +	/* send command for enable/disable HW patrol scrub */
> +	ret = ras2_send_pcc_cmd(ras2_ctx, RAS2_PCC_CMD_EXEC);
> +	if (ret) {
> +		dev_err(ras2_ctx->dev,
> +			"%s: failed to enable/disable background patrol scrubbing\n",
> +			__func__);
> +		return ret;
> +	}
> +
> +	return 0;
> +}
> +static int ras2_set_patrol_scrub_params(struct ras2_context *ras2_ctx,
> +					struct ras2_scrub_params *params, u8 param_type)
> +{
> +	struct acpi_ras2_shared_memory  __iomem *generic_comm_base;
> +	struct acpi_ras2_patrol_scrub_parameter __iomem *patrol_scrub_params;
> +
> +	if (!ras2_ctx || !ras2_ctx->pcc_comm_addr)
> +		return -EFAULT;
> +
> +	generic_comm_base = ras2_ctx->pcc_comm_addr;
> +	patrol_scrub_params = ras2_ctx->pcc_comm_addr + sizeof(*generic_comm_base);
> +
> +	guard(spinlock_irqsave)(&ras2_ctx->spinlock);
> +	patrol_scrub_params->header.type = RAS2_TYPE_PATROL_SCRUB;
> +	if (param_type == RAS2_MEM_SCRUB_PARAM_ADDR_BASE && params->addr_base) {
> +		patrol_scrub_params->requested_address_range[0] = params->addr_base;
> +	} else if (param_type == RAS2_MEM_SCRUB_PARAM_ADDR_SIZE && params->addr_size) {
> +		patrol_scrub_params->requested_address_range[1] = params->addr_size;
> +	} else if (param_type == RAS2_MEM_SCRUB_PARAM_RATE) {
> +		patrol_scrub_params->scrub_params_in &= ~RAS2_PATROL_SCRUB_RATE_IN_MASK;
> +		patrol_scrub_params->scrub_params_in |= FIELD_PREP(RAS2_PATROL_SCRUB_RATE_IN_MASK,
> +								   params->rate);
> +	} else {
> +		dev_err(ras2_ctx->dev, "Invalid patrol scrub parameter to set\n");
> +		return -EINVAL;
> +	}
> +
> +	return 0;
> +}
> +
> +static const struct ras2_hw_scrub_ops ras2_hw_ops = {
> +	.enable_scrub = ras2_enable_patrol_scrub,
> +	.enable_background_scrub = ras2_enable_background_scrub,
> +	.get_scrub_params = ras2_get_patrol_scrub_params,
> +	.set_scrub_params = ras2_set_patrol_scrub_params,
> +};
> +
> +static const struct scrub_ops ras2_scrub_ops = {
> +	.is_visible = ras2_hw_scrub_is_visible,
> +	.read = ras2_hw_scrub_read,
> +	.write = ras2_hw_scrub_write,
> +	.read_string = ras2_hw_scrub_read_strings,
> +};
> +
> +static DEFINE_IDA(ras2_ida);
> +
> +static void devm_ras2_release(void *ctx)
> +{
> +	struct ras2_context *ras2_ctx = ctx;
> +
> +	ida_free(&ras2_ida, ras2_ctx->id);
> +	ras2_unregister_pcc_channel(ras2_ctx);
> +}
> +
> +static int ras2_probe(struct platform_device *pdev)
> +{
> +	int ret, id;
> +	struct mbox_client *cl;
> +	struct device *hw_scrub_dev;
> +	struct ras2_context *ras2_ctx;
> +	char scrub_name[RAS2_MAX_NAME_LENGTH];
> +
> +	ras2_ctx = devm_kzalloc(&pdev->dev, sizeof(*ras2_ctx), GFP_KERNEL);
> +	if (!ras2_ctx)
> +		return -ENOMEM;
> +
> +	ras2_ctx->dev = &pdev->dev;
> +	ras2_ctx->ops = &ras2_hw_ops;
> +	spin_lock_init(&ras2_ctx->spinlock);
> +	platform_set_drvdata(pdev, ras2_ctx);
> +
> +	cl = &ras2_ctx->mbox_client;
> +	/* Request mailbox channel */
> +	cl->dev = &pdev->dev;
> +	cl->tx_done = ras2_tx_done;
> +	cl->knows_txdone = true;
> +	ras2_ctx->pcc_subspace_idx = *((int *)pdev->dev.platform_data);
> +	dev_dbg(&pdev->dev, "pcc-subspace-id=%d\n", ras2_ctx->pcc_subspace_idx);
> +	ret = ras2_register_pcc_channel(ras2_ctx);

In our enabling activities, we have found a challenge here.
Our hardware has a single PCC channel corresponding to a single
platform-wide scrub interface. This driver, following the ACPI spec,
will create a new scrub node for each NUMA node. However, for us,
this means that each scrub device will try to map the same PCC channel,
and this causes an error.
> +	if (ret < 0)
> +		return ret;
> +
> +	ret = devm_add_action_or_reset(&pdev->dev, devm_ras2_release, ras2_ctx);
> +	if (ret < 0)
> +		return ret;
> +
> +	if (ras2_is_patrol_scrub_support(ras2_ctx)) {
> +		id = ida_alloc(&ras2_ida, GFP_KERNEL);
> +		if (id < 0)
> +			return id;
> +		ras2_ctx->id = id;
> +		snprintf(scrub_name, sizeof(scrub_name), "%s%d", RAS2_SCRUB, id);
> +		dev_set_name(&pdev->dev, RAS2_ID_FORMAT, id);
> +		hw_scrub_dev = devm_scrub_device_register(&pdev->dev, scrub_name,
> +							  ras2_ctx, &ras2_scrub_ops,
> +							  0, NULL);
> +		if (PTR_ERR_OR_ZERO(hw_scrub_dev))
> +			return PTR_ERR_OR_ZERO(hw_scrub_dev);
> +	}
> +	ras2_ctx->scrub_dev = hw_scrub_dev;
> +
> +	return 0;
> +}
Jonathan Cameron April 2, 2024, 10:17 a.m. UTC | #3
On Thu, 28 Mar 2024 11:23:38 -0400
Yazen Ghannam <yazen.ghannam@amd.com> wrote:

> On 2/23/2024 9:37 AM, shiju.jose@huawei.com wrote:
> > From: Shiju Jose <shiju.jose@huawei.com>
> > 
> > Memory RAS2 driver binds to the platform device add by the ACPI RAS2
> > driver.
> > Driver registers the PCC channel for communicating with the ACPI compliant
> > platform that contains RAS2 command support in the hardware.
> > 
> > Add interface functions to support configuring the parameters of HW patrol
> > scrubs in the system, which exposed to the kernel via the RAS2 and PCC,
> > using the RAS2 commands.
> > 
> > Add support for RAS2 platform devices to register with scrub subsystem
> > driver. This enables user to configure the parameters of HW patrol scrubs,
> > which exposed to the kernel via the RAS2 table, through the scrub sysfs
> > attributes.
> > 
> > Open Question:
> > Sysfs scrub control attribute "enable_background_scrub" is added for RAS2,
> > based on the feedback from Bill Schwartz <wschwartz@amperecomputing.com
> > on v4 to enable/disable the background_scrubbing in the platform as defined in the
> > “Configure Scrub Parameters [INPUT]“ field  in RAS2 Table 5.87: Parameter Block
> > Structure for PATROL_SCRUB.
> > Is it a right approach to support "enable_background_scrub" in the sysfs
> > scrub control?
> > 
> > Signed-off-by: Shiju Jose <shiju.jose@huawei.com>
> > ---
> >  drivers/memory/Kconfig       |  14 ++
> >  drivers/memory/Makefile      |   2 +
> >  drivers/memory/ras2.c        | 364 +++++++++++++++++++++++++++++++++++
> >  drivers/memory/ras2_common.c | 282 +++++++++++++++++++++++++++
> >  include/memory/ras2.h        |  88 +++++++++
> >  5 files changed, 750 insertions(+)
> >  create mode 100644 drivers/memory/ras2.c
> >  create mode 100644 drivers/memory/ras2_common.c
> >  create mode 100755 include/memory/ras2.h
> >   
> 
> Sorry if this was already covered, but why not put the common scrub and ras2
> changes under /drivers/ras/?

Hi Yazen

Location / naming etc is definitely an open question.
Given the OCP RAS API has repeatedly come up in discussions (and that
has a much wider scope), a RAS focused location may well make sense + some
renaming to avoid being memory scrub specific.

Jonathan

> 
> Thanks,
> Yazen
Shiju Jose April 3, 2024, 2:03 p.m. UTC | #4
Hi Daniel,

>-----Original Message-----
>From: Daniel Ferguson <danielf@os.amperecomputing.com>
>Sent: 28 March 2024 23:42
>To: Shiju Jose <shiju.jose@huawei.com>; linux-cxl@vger.kernel.org; linux-
>acpi@vger.kernel.org; linux-mm@kvack.org; dan.j.williams@intel.com;
>dave@stgolabs.net; Jonathan Cameron <jonathan.cameron@huawei.com>;
>dave.jiang@intel.com; alison.schofield@intel.com; vishal.l.verma@intel.com;
>ira.weiny@intel.com
>Cc: linux-edac@vger.kernel.org; linux-kernel@vger.kernel.org;
>david@redhat.com; Vilas.Sridharan@amd.com; leo.duran@amd.com;
>Yazen.Ghannam@amd.com; rientjes@google.com; jiaqiyan@google.com;
>tony.luck@intel.com; Jon.Grimm@amd.com; dave.hansen@linux.intel.com;
>rafael@kernel.org; lenb@kernel.org; naoya.horiguchi@nec.com;
>james.morse@arm.com; jthoughton@google.com; somasundaram.a@hpe.com;
>erdemaktas@google.com; pgonda@google.com; duenwen@google.com;
>mike.malvestuto@intel.com; gthelen@google.com;
>wschwartz@amperecomputing.com; dferguson@amperecomputing.com;
>tanxiaofei <tanxiaofei@huawei.com>; Zengtao (B) <prime.zeng@hisilicon.com>;
>kangkang.shen@futurewei.com; wanghuiqiang <wanghuiqiang@huawei.com>;
>Linuxarm <linuxarm@huawei.com>; wbs@os.amperecomputing.com
>Subject: Re: [RFC PATCH v7 12/12] memory: RAS2: Add memory RAS2 driver
>
>> +/*
...
>> +
>> +static int ras2_probe(struct platform_device *pdev) {
>> +	int ret, id;
>> +	struct mbox_client *cl;
>> +	struct device *hw_scrub_dev;
>> +	struct ras2_context *ras2_ctx;
>> +	char scrub_name[RAS2_MAX_NAME_LENGTH];
>> +
>> +	ras2_ctx = devm_kzalloc(&pdev->dev, sizeof(*ras2_ctx), GFP_KERNEL);
>> +	if (!ras2_ctx)
>> +		return -ENOMEM;
>> +
>> +	ras2_ctx->dev = &pdev->dev;
>> +	ras2_ctx->ops = &ras2_hw_ops;
>> +	spin_lock_init(&ras2_ctx->spinlock);
>> +	platform_set_drvdata(pdev, ras2_ctx);
>> +
>> +	cl = &ras2_ctx->mbox_client;
>> +	/* Request mailbox channel */
>> +	cl->dev = &pdev->dev;
>> +	cl->tx_done = ras2_tx_done;
>> +	cl->knows_txdone = true;
>> +	ras2_ctx->pcc_subspace_idx = *((int *)pdev->dev.platform_data);
>> +	dev_dbg(&pdev->dev, "pcc-subspace-id=%d\n", ras2_ctx-
>>pcc_subspace_idx);
>> +	ret = ras2_register_pcc_channel(ras2_ctx);
>
>In our enabling activities, we have found a challenge here.
>Our hardware has a single PCC channel corresponding to a single platform-wide
>scrub interface. This driver, following the ACPI spec, will create a new scrub
>node for each NUMA node. However, for us, this means that each scrub device
>will try to map the same PCC channel, and this causes an error.

Is failing to probe cleanly is enough for your platform?  i.e. put any error messages as dev_dbg()
or whichever one causes this problem.
>> +	if (ret < 0)
>> +		return ret;
>> +
>> +	ret = devm_add_action_or_reset(&pdev->dev, devm_ras2_release,
>ras2_ctx);
>> +	if (ret < 0)
>> +		return ret;
>> +
>> +	if (ras2_is_patrol_scrub_support(ras2_ctx)) {
>> +		id = ida_alloc(&ras2_ida, GFP_KERNEL);
>> +		if (id < 0)
>> +			return id;
>> +		ras2_ctx->id = id;
>> +		snprintf(scrub_name, sizeof(scrub_name), "%s%d",
>RAS2_SCRUB, id);
>> +		dev_set_name(&pdev->dev, RAS2_ID_FORMAT, id);
>> +		hw_scrub_dev = devm_scrub_device_register(&pdev->dev,
>scrub_name,
>> +							  ras2_ctx,
>&ras2_scrub_ops,
>> +							  0, NULL);
>> +		if (PTR_ERR_OR_ZERO(hw_scrub_dev))
>> +			return PTR_ERR_OR_ZERO(hw_scrub_dev);
>> +	}
>> +	ras2_ctx->scrub_dev = hw_scrub_dev;
>> +
>> +	return 0;
>> +}
>
Thanks,
Shiju
diff mbox series

Patch

diff --git a/drivers/memory/Kconfig b/drivers/memory/Kconfig
index d2e015c09d83..705f346f23de 100644
--- a/drivers/memory/Kconfig
+++ b/drivers/memory/Kconfig
@@ -225,6 +225,20 @@  config STM32_FMC2_EBI
 	  devices (like SRAM, ethernet adapters, FPGAs, LCD displays, ...) on
 	  SOCs containing the FMC2 External Bus Interface.
 
+config MEM_RAS2
+	bool "Memory RAS2 driver"
+	depends on ACPI_RAS2
+	depends on SCRUB
+	help
+	  The driver bound to the platform device added by the ACPI RAS2
+	  driver. Driver registers the PCC channel for communicating with
+	  the ACPI compliant platform that contains RAS2 command support
+	  in the hardware.
+	  Registers with the scrub configure driver to provide sysfs interfaces
+	  for configuring the hw patrol scrubber in the system, which exposed
+	  via the ACPI RAS2 table and PCC. Provides the interface functions
+	  support configuring the HW patrol scrubbers in the system.
+
 source "drivers/memory/samsung/Kconfig"
 source "drivers/memory/tegra/Kconfig"
 source "drivers/memory/scrub/Kconfig"
diff --git a/drivers/memory/Makefile b/drivers/memory/Makefile
index 4b37312cb342..52afd9d2259a 100644
--- a/drivers/memory/Makefile
+++ b/drivers/memory/Makefile
@@ -7,6 +7,8 @@  obj-$(CONFIG_DDR)		+= jedec_ddr_data.o
 ifeq ($(CONFIG_DDR),y)
 obj-$(CONFIG_OF)		+= of_memory.o
 endif
+obj-$(CONFIG_MEM_RAS2)		+= ras2_common.o ras2.o
+
 obj-$(CONFIG_ARM_PL172_MPMC)	+= pl172.o
 obj-$(CONFIG_ATMEL_EBI)		+= atmel-ebi.o
 obj-$(CONFIG_BRCMSTB_DPFE)	+= brcmstb_dpfe.o
diff --git a/drivers/memory/ras2.c b/drivers/memory/ras2.c
new file mode 100644
index 000000000000..12fd1f4580d4
--- /dev/null
+++ b/drivers/memory/ras2.c
@@ -0,0 +1,364 @@ 
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * ras2.c - ACPI RAS2 memory driver
+ *
+ * Copyright (c) 2023 HiSilicon Limited.
+ *
+ *  - Registers the PCC channel for communicating with the
+ *    ACPI compliant platform that contains RAS2 command
+ *    support in the hardware.
+ *  - Provides functions to configure HW patrol scrubs
+ *    in the system.
+ *  - Registers with the scrub configure driver for the
+ *    hw patrol scrub in the system, which exposed via
+ *    the ACPI RAS2 table and PCC.
+ */
+
+#define pr_fmt(fmt)	"MEMORY RAS2: " fmt
+
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/cleanup.h>
+
+#include <acpi/ras2_acpi.h>
+#include <memory/ras2.h>
+
+/* RAS2 specific definitions. */
+#define RAS2_SCRUB	"ras2_scrub"
+#define RAS2_ID_FORMAT RAS2_SCRUB "%d"
+#define RAS2_SUPPORT_HW_PARTOL_SCRUB	BIT(0)
+#define RAS2_TYPE_PATROL_SCRUB	0x0000
+
+#define RAS2_GET_PATROL_PARAMETERS	0x01
+#define	RAS2_START_PATROL_SCRUBBER	0x02
+#define	RAS2_STOP_PATROL_SCRUBBER	0x03
+
+#define RAS2_PATROL_SCRUB_RATE_VALID	BIT(0)
+#define RAS2_PATROL_SCRUB_RATE_IN_MASK	GENMASK(15, 8)
+#define RAS2_PATROL_SCRUB_EN_BACKGROUND	BIT(0)
+#define RAS2_PATROL_SCRUB_RATE_OUT_MASK	GENMASK(7, 0)
+#define RAS2_PATROL_SCRUB_MIN_RATE_OUT_MASK	GENMASK(15, 8)
+#define RAS2_PATROL_SCRUB_MAX_RATE_OUT_MASK	GENMASK(23, 16)
+
+static void ras2_tx_done(struct mbox_client *cl, void *msg, int ret)
+{
+	if (ret) {
+		dev_dbg(cl->dev, "TX did not complete: CMD sent:%x, ret:%d\n",
+			*(u16 *)msg, ret);
+	} else {
+		dev_dbg(cl->dev, "TX completed. CMD sent:%x, ret:%d\n",
+			*(u16 *)msg, ret);
+	}
+}
+
+/*
+ * The below functions are exposed to OSPM, to query, configure and
+ * initiate memory patrol scrub.
+ */
+static int ras2_is_patrol_scrub_support(struct ras2_context *ras2_ctx)
+{
+	int ret;
+	struct acpi_ras2_shared_memory  __iomem *generic_comm_base;
+
+	if (!ras2_ctx || !ras2_ctx->pcc_comm_addr)
+		return -EFAULT;
+
+	generic_comm_base = ras2_ctx->pcc_comm_addr;
+	guard(spinlock_irqsave)(&ras2_ctx->spinlock);
+	generic_comm_base->set_capabilities[0] = 0;
+
+	/* send command for reading RAS2 capabilities */
+	ret = ras2_send_pcc_cmd(ras2_ctx, RAS2_PCC_CMD_EXEC);
+	if (ret) {
+		dev_err(ras2_ctx->dev,
+			"%s: ras2_send_pcc_cmd failed\n", __func__);
+		return ret;
+	}
+
+	return generic_comm_base->features[0] & RAS2_SUPPORT_HW_PARTOL_SCRUB;
+}
+
+static int ras2_get_patrol_scrub_params(struct ras2_context *ras2_ctx,
+					struct ras2_scrub_params *params)
+{
+	int ret = 0;
+	u8  min_supp_scrub_rate, max_supp_scrub_rate;
+	struct acpi_ras2_shared_memory  __iomem *generic_comm_base;
+	struct acpi_ras2_patrol_scrub_parameter __iomem *patrol_scrub_params;
+
+	if (!ras2_ctx || !ras2_ctx->pcc_comm_addr)
+		return -EFAULT;
+
+	generic_comm_base = ras2_ctx->pcc_comm_addr;
+	patrol_scrub_params = ras2_ctx->pcc_comm_addr + sizeof(*generic_comm_base);
+
+	guard(spinlock_irqsave)(&ras2_ctx->spinlock);
+	generic_comm_base->set_capabilities[0] = RAS2_SUPPORT_HW_PARTOL_SCRUB;
+	/* send command for reading RAS2 capabilities */
+	ret = ras2_send_pcc_cmd(ras2_ctx, RAS2_PCC_CMD_EXEC);
+	if (ret) {
+		dev_err(ras2_ctx->dev,
+			"%s: ras2_send_pcc_cmd failed\n", __func__);
+		return ret;
+	}
+
+	if (!(generic_comm_base->features[0] & RAS2_SUPPORT_HW_PARTOL_SCRUB) ||
+	    !(generic_comm_base->num_parameter_blocks)) {
+		dev_err(ras2_ctx->dev,
+			"%s: Platform does not support HW Patrol Scrubber\n", __func__);
+		return -EOPNOTSUPP;
+	}
+
+	if (!patrol_scrub_params->requested_address_range[1]) {
+		dev_err(ras2_ctx->dev,
+			"%s: Invalid requested address range, \
+			requested_address_range[0]=0x%llx \
+			requested_address_range[1]=0x%llx\n",
+			__func__,
+			patrol_scrub_params->requested_address_range[0],
+			patrol_scrub_params->requested_address_range[1]);
+		return -EOPNOTSUPP;
+	}
+
+	generic_comm_base->set_capabilities[0] = RAS2_SUPPORT_HW_PARTOL_SCRUB;
+	patrol_scrub_params->header.type = RAS2_TYPE_PATROL_SCRUB;
+	patrol_scrub_params->patrol_scrub_command = RAS2_GET_PATROL_PARAMETERS;
+
+	/* send command for reading the HW patrol scrub parameters */
+	ret = ras2_send_pcc_cmd(ras2_ctx, RAS2_PCC_CMD_EXEC);
+	if (ret) {
+		dev_err(ras2_ctx->dev,
+			"%s: failed to read HW patrol scrub parameters\n",
+			__func__);
+		return ret;
+	}
+
+	/* copy output scrub parameters */
+	params->addr_base = patrol_scrub_params->actual_address_range[0];
+	params->addr_size = patrol_scrub_params->actual_address_range[1];
+	params->flags = patrol_scrub_params->flags;
+	params->rate = FIELD_GET(RAS2_PATROL_SCRUB_RATE_OUT_MASK,
+				 patrol_scrub_params->scrub_params_out);
+	min_supp_scrub_rate = FIELD_GET(RAS2_PATROL_SCRUB_MIN_RATE_OUT_MASK,
+					patrol_scrub_params->scrub_params_out);
+	max_supp_scrub_rate = FIELD_GET(RAS2_PATROL_SCRUB_MAX_RATE_OUT_MASK,
+					patrol_scrub_params->scrub_params_out);
+	snprintf(params->rate_avail, RAS2_MAX_RATE_RANGE_LENGTH,
+		 "%d-%d", min_supp_scrub_rate, max_supp_scrub_rate);
+
+	return 0;
+}
+
+static int ras2_enable_patrol_scrub(struct ras2_context *ras2_ctx, bool enable)
+{
+	int ret = 0;
+	struct ras2_scrub_params params;
+	struct acpi_ras2_shared_memory  __iomem *generic_comm_base;
+	u8 scrub_rate_to_set, min_supp_scrub_rate, max_supp_scrub_rate;
+	struct acpi_ras2_patrol_scrub_parameter __iomem *patrol_scrub_params;
+
+	if (!ras2_ctx || !ras2_ctx->pcc_comm_addr)
+		return -EFAULT;
+
+	generic_comm_base = ras2_ctx->pcc_comm_addr;
+	patrol_scrub_params = ras2_ctx->pcc_comm_addr + sizeof(*generic_comm_base);
+
+	if (enable) {
+		ret = ras2_get_patrol_scrub_params(ras2_ctx, &params);
+		if (ret)
+			return ret;
+	}
+
+	guard(spinlock_irqsave)(&ras2_ctx->spinlock);
+	generic_comm_base->set_capabilities[0] = RAS2_SUPPORT_HW_PARTOL_SCRUB;
+	patrol_scrub_params->header.type = RAS2_TYPE_PATROL_SCRUB;
+
+	if (enable) {
+		patrol_scrub_params->patrol_scrub_command = RAS2_START_PATROL_SCRUBBER;
+		patrol_scrub_params->requested_address_range[0] = params.addr_base;
+		patrol_scrub_params->requested_address_range[1] = params.addr_size;
+
+		scrub_rate_to_set = FIELD_GET(RAS2_PATROL_SCRUB_RATE_IN_MASK,
+					      patrol_scrub_params->scrub_params_in);
+		min_supp_scrub_rate = FIELD_GET(RAS2_PATROL_SCRUB_MIN_RATE_OUT_MASK,
+						patrol_scrub_params->scrub_params_out);
+		max_supp_scrub_rate = FIELD_GET(RAS2_PATROL_SCRUB_MAX_RATE_OUT_MASK,
+						patrol_scrub_params->scrub_params_out);
+		if (scrub_rate_to_set < min_supp_scrub_rate ||
+		    scrub_rate_to_set > max_supp_scrub_rate) {
+			dev_warn(ras2_ctx->dev,
+				 "patrol scrub rate to set is out of the supported range\n");
+			dev_warn(ras2_ctx->dev,
+				 "min_supp_scrub_rate=%d max_supp_scrub_rate=%d\n",
+				 min_supp_scrub_rate, max_supp_scrub_rate);
+			return -EINVAL;
+		}
+	} else {
+		patrol_scrub_params->patrol_scrub_command = RAS2_STOP_PATROL_SCRUBBER;
+	}
+
+	/* send command for enable/disable HW patrol scrub */
+	ret = ras2_send_pcc_cmd(ras2_ctx, RAS2_PCC_CMD_EXEC);
+	if (ret) {
+		pr_err("%s: failed to enable/disable the HW patrol scrub\n", __func__);
+		return ret;
+	}
+
+	return 0;
+}
+
+static int ras2_enable_background_scrub(struct ras2_context *ras2_ctx, bool enable)
+{
+	int ret;
+	struct acpi_ras2_shared_memory  __iomem *generic_comm_base;
+	struct acpi_ras2_patrol_scrub_parameter __iomem *patrol_scrub_params;
+
+	if (!ras2_ctx || !ras2_ctx->pcc_comm_addr)
+		return -EFAULT;
+
+	generic_comm_base = ras2_ctx->pcc_comm_addr;
+	patrol_scrub_params = ras2_ctx->pcc_comm_addr + sizeof(*generic_comm_base);
+
+	guard(spinlock_irqsave)(&ras2_ctx->spinlock);
+	generic_comm_base->set_capabilities[0] = RAS2_SUPPORT_HW_PARTOL_SCRUB;
+	patrol_scrub_params->header.type = RAS2_TYPE_PATROL_SCRUB;
+	patrol_scrub_params->patrol_scrub_command = RAS2_START_PATROL_SCRUBBER;
+
+	patrol_scrub_params->scrub_params_in &= ~RAS2_PATROL_SCRUB_EN_BACKGROUND;
+	patrol_scrub_params->scrub_params_in |= FIELD_PREP(RAS2_PATROL_SCRUB_EN_BACKGROUND,
+							   enable);
+
+	/* send command for enable/disable HW patrol scrub */
+	ret = ras2_send_pcc_cmd(ras2_ctx, RAS2_PCC_CMD_EXEC);
+	if (ret) {
+		dev_err(ras2_ctx->dev,
+			"%s: failed to enable/disable background patrol scrubbing\n",
+			__func__);
+		return ret;
+	}
+
+	return 0;
+}
+static int ras2_set_patrol_scrub_params(struct ras2_context *ras2_ctx,
+					struct ras2_scrub_params *params, u8 param_type)
+{
+	struct acpi_ras2_shared_memory  __iomem *generic_comm_base;
+	struct acpi_ras2_patrol_scrub_parameter __iomem *patrol_scrub_params;
+
+	if (!ras2_ctx || !ras2_ctx->pcc_comm_addr)
+		return -EFAULT;
+
+	generic_comm_base = ras2_ctx->pcc_comm_addr;
+	patrol_scrub_params = ras2_ctx->pcc_comm_addr + sizeof(*generic_comm_base);
+
+	guard(spinlock_irqsave)(&ras2_ctx->spinlock);
+	patrol_scrub_params->header.type = RAS2_TYPE_PATROL_SCRUB;
+	if (param_type == RAS2_MEM_SCRUB_PARAM_ADDR_BASE && params->addr_base) {
+		patrol_scrub_params->requested_address_range[0] = params->addr_base;
+	} else if (param_type == RAS2_MEM_SCRUB_PARAM_ADDR_SIZE && params->addr_size) {
+		patrol_scrub_params->requested_address_range[1] = params->addr_size;
+	} else if (param_type == RAS2_MEM_SCRUB_PARAM_RATE) {
+		patrol_scrub_params->scrub_params_in &= ~RAS2_PATROL_SCRUB_RATE_IN_MASK;
+		patrol_scrub_params->scrub_params_in |= FIELD_PREP(RAS2_PATROL_SCRUB_RATE_IN_MASK,
+								   params->rate);
+	} else {
+		dev_err(ras2_ctx->dev, "Invalid patrol scrub parameter to set\n");
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static const struct ras2_hw_scrub_ops ras2_hw_ops = {
+	.enable_scrub = ras2_enable_patrol_scrub,
+	.enable_background_scrub = ras2_enable_background_scrub,
+	.get_scrub_params = ras2_get_patrol_scrub_params,
+	.set_scrub_params = ras2_set_patrol_scrub_params,
+};
+
+static const struct scrub_ops ras2_scrub_ops = {
+	.is_visible = ras2_hw_scrub_is_visible,
+	.read = ras2_hw_scrub_read,
+	.write = ras2_hw_scrub_write,
+	.read_string = ras2_hw_scrub_read_strings,
+};
+
+static DEFINE_IDA(ras2_ida);
+
+static void devm_ras2_release(void *ctx)
+{
+	struct ras2_context *ras2_ctx = ctx;
+
+	ida_free(&ras2_ida, ras2_ctx->id);
+	ras2_unregister_pcc_channel(ras2_ctx);
+}
+
+static int ras2_probe(struct platform_device *pdev)
+{
+	int ret, id;
+	struct mbox_client *cl;
+	struct device *hw_scrub_dev;
+	struct ras2_context *ras2_ctx;
+	char scrub_name[RAS2_MAX_NAME_LENGTH];
+
+	ras2_ctx = devm_kzalloc(&pdev->dev, sizeof(*ras2_ctx), GFP_KERNEL);
+	if (!ras2_ctx)
+		return -ENOMEM;
+
+	ras2_ctx->dev = &pdev->dev;
+	ras2_ctx->ops = &ras2_hw_ops;
+	spin_lock_init(&ras2_ctx->spinlock);
+	platform_set_drvdata(pdev, ras2_ctx);
+
+	cl = &ras2_ctx->mbox_client;
+	/* Request mailbox channel */
+	cl->dev = &pdev->dev;
+	cl->tx_done = ras2_tx_done;
+	cl->knows_txdone = true;
+	ras2_ctx->pcc_subspace_idx = *((int *)pdev->dev.platform_data);
+	dev_dbg(&pdev->dev, "pcc-subspace-id=%d\n", ras2_ctx->pcc_subspace_idx);
+	ret = ras2_register_pcc_channel(ras2_ctx);
+	if (ret < 0)
+		return ret;
+
+	ret = devm_add_action_or_reset(&pdev->dev, devm_ras2_release, ras2_ctx);
+	if (ret < 0)
+		return ret;
+
+	if (ras2_is_patrol_scrub_support(ras2_ctx)) {
+		id = ida_alloc(&ras2_ida, GFP_KERNEL);
+		if (id < 0)
+			return id;
+		ras2_ctx->id = id;
+		snprintf(scrub_name, sizeof(scrub_name), "%s%d", RAS2_SCRUB, id);
+		dev_set_name(&pdev->dev, RAS2_ID_FORMAT, id);
+		hw_scrub_dev = devm_scrub_device_register(&pdev->dev, scrub_name,
+							  ras2_ctx, &ras2_scrub_ops,
+							  0, NULL);
+		if (PTR_ERR_OR_ZERO(hw_scrub_dev))
+			return PTR_ERR_OR_ZERO(hw_scrub_dev);
+	}
+	ras2_ctx->scrub_dev = hw_scrub_dev;
+
+	return 0;
+}
+
+static const struct platform_device_id ras2_id_table[] = {
+	{ .name = "ras2", },
+	{ }
+};
+MODULE_DEVICE_TABLE(platform, ras2_id_table);
+
+static struct platform_driver ras2_driver = {
+	.probe = ras2_probe,
+	.driver = {
+		.name = "ras2",
+		.suppress_bind_attrs = true,
+	},
+	.id_table = ras2_id_table,
+};
+module_driver(ras2_driver, platform_driver_register, platform_driver_unregister);
+
+MODULE_DESCRIPTION("ras2 memory driver");
+MODULE_LICENSE("GPL");
diff --git a/drivers/memory/ras2_common.c b/drivers/memory/ras2_common.c
new file mode 100644
index 000000000000..97e1852e9fd7
--- /dev/null
+++ b/drivers/memory/ras2_common.c
@@ -0,0 +1,282 @@ 
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Common functions for memory RAS2 driver
+ *
+ * Copyright (c) 2024 HiSilicon Limited.
+ *
+ * This driver implements call back functions for the scrub
+ * configure driver to configure the parameters of the hw patrol
+ * scrubbers in the system, which exposed via the ACPI AS2
+ * table and PCC.
+ */
+
+#include <linux/acpi.h>
+#include <linux/io.h>
+#include <linux/interrupt.h>
+#include <linux/mailbox_controller.h>
+#include <linux/mailbox_client.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+
+#include <acpi/ras2_acpi.h>
+#include <memory/ras2.h>
+
+static int enable_write(struct ras2_context *ras2_ctx, long val)
+{
+	int ret;
+	bool enable = val;
+
+	ret = ras2_ctx->ops->enable_scrub(ras2_ctx, enable);
+	if (ret) {
+		dev_err(ras2_ctx->dev,
+			"enable patrol scrub fail, enable=%d ret=%d\n",
+			enable, ret);
+		return ret;
+	}
+
+	return 0;
+}
+
+static int enable_background_scrub_write(struct ras2_context *ras2_ctx, long val)
+{
+	int ret;
+	bool enable = val;
+
+	ret = ras2_ctx->ops->enable_background_scrub(ras2_ctx, enable);
+	if (ret) {
+		dev_err(ras2_ctx->dev,
+			"enable background patrol scrub fail, enable=%d ret=%d\n",
+			enable, ret);
+		return ret;
+	}
+
+	return 0;
+}
+
+static int addr_base_read(struct ras2_context *ras2_ctx, u64 *val)
+{
+	int ret;
+	struct ras2_scrub_params params;
+
+	ret = ras2_ctx->ops->get_scrub_params(ras2_ctx, &params);
+	if (ret) {
+		dev_err(ras2_ctx->dev,
+			"get patrol scrub params fail ret=%d\n", ret);
+		return ret;
+	}
+	*val = params.addr_base;
+
+	return 0;
+}
+
+static int addr_base_write(struct ras2_context *ras2_ctx, u64 val)
+{
+	int ret;
+	struct ras2_scrub_params params;
+
+	params.addr_base = val;
+	ret = ras2_ctx->ops->set_scrub_params(ras2_ctx, &params,
+					      RAS2_MEM_SCRUB_PARAM_ADDR_BASE);
+	if (ret) {
+		dev_err(ras2_ctx->dev,
+			"set patrol scrub params for addr_base fail ret=%d\n",
+			ret);
+		return ret;
+	}
+
+	return 0;
+}
+
+static int addr_size_read(struct ras2_context *ras2_ctx, u64 *val)
+{
+	int ret;
+	struct ras2_scrub_params params;
+
+	ret = ras2_ctx->ops->get_scrub_params(ras2_ctx, &params);
+	if (ret) {
+		dev_err(ras2_ctx->dev,
+			"get patrol scrub params fail ret=%d\n", ret);
+		return ret;
+	}
+	*val = params.addr_size;
+
+	return 0;
+}
+
+static int addr_size_write(struct ras2_context *ras2_ctx, u64 val)
+{
+	int ret;
+	struct ras2_scrub_params params;
+
+	params.addr_size = val;
+	ret = ras2_ctx->ops->set_scrub_params(ras2_ctx, &params,
+					      RAS2_MEM_SCRUB_PARAM_ADDR_SIZE);
+	if (ret) {
+		dev_err(ras2_ctx->dev,
+			"set patrol scrub params for addr_size fail ret=%d\n",
+			ret);
+		return ret;
+	}
+
+	return 0;
+}
+
+static int rate_read(struct ras2_context *ras2_ctx, u64 *val)
+{
+	int ret;
+	struct ras2_scrub_params params;
+
+	ret = ras2_ctx->ops->get_scrub_params(ras2_ctx, &params);
+	if (ret) {
+		dev_err(ras2_ctx->dev, "get patrol scrub params fail ret=%d\n",
+			ret);
+		return ret;
+	}
+	*val = params.rate;
+
+	return 0;
+}
+
+static int rate_write(struct ras2_context *ras2_ctx, long val)
+{
+	int ret;
+	struct ras2_scrub_params params;
+
+	params.rate = val;
+	ret = ras2_ctx->ops->set_scrub_params(ras2_ctx, &params,
+					      RAS2_MEM_SCRUB_PARAM_RATE);
+	if (ret) {
+		dev_err(ras2_ctx->dev,
+			"set patrol scrub params for rate fail ret=%d\n", ret);
+		return ret;
+	}
+
+	return 0;
+}
+
+static int rate_available_read(struct ras2_context *ras2_ctx, char *buf)
+{
+	int ret;
+	struct ras2_scrub_params params;
+
+	ret = ras2_ctx->ops->get_scrub_params(ras2_ctx, &params);
+	if (ret) {
+		dev_err(ras2_ctx->dev,
+			"get patrol scrub params fail ret=%d\n", ret);
+		return ret;
+	}
+
+	sprintf(buf, "%s\n", params.rate_avail);
+
+	return 0;
+}
+
+/**
+ * ras2_hw_scrub_is_visible() - Callback to return attribute visibility
+ * @drv_data: Pointer to driver-private data structure passed
+ *	      as argument to devm_scrub_device_register().
+ * @attr_id: Scrub attribute
+ * @mode: attribute's mode
+ * @region_id: ID of the memory region
+ *
+ * Returns: 0 on success, an error otherwise
+ */
+umode_t ras2_hw_scrub_is_visible(struct device *dev, u32 attr_id,
+				 umode_t mode, int region_id)
+{
+	switch (attr_id) {
+	case scrub_rate_available:
+	case scrub_enable:
+	case scrub_enable_background_scrub:
+	case scrub_addr_base:
+	case scrub_addr_size:
+	case scrub_rate:
+		return mode;
+	default:
+		return 0;
+	}
+}
+
+/**
+ * ras2_hw_scrub_read() - Read callback for data attributes
+ * @device: Pointer to scrub device
+ * @attr_id: Scrub attribute
+ * @region_id: ID of the memory region
+ * @val: Pointer to the returned data
+ *
+ * Returns: 0 on success, an error otherwise
+ */
+int ras2_hw_scrub_read(struct device *device, u32 attr_id,
+		       int region_id, u64 *val)
+{
+	struct ras2_context *ras2_ctx;
+
+	ras2_ctx = dev_get_drvdata(device);
+
+	switch (attr_id) {
+	case scrub_addr_base:
+		return addr_base_read(ras2_ctx, val);
+	case scrub_addr_size:
+		return addr_size_read(ras2_ctx, val);
+	case scrub_rate:
+		return rate_read(ras2_ctx, val);
+	default:
+		return -EOPNOTSUPP;
+	}
+}
+
+/**
+ * ras2_hw_scrub_write() - Write callback for data attributes
+ * @device: Pointer to scrub device
+ * @attr_id: Scrub attribute
+ * @region_id: ID of the memory region
+ * @val: Value to write
+ *
+ * Returns: 0 on success, an error otherwise
+ */
+int ras2_hw_scrub_write(struct device *device, u32 attr_id,
+			int region_id, u64 val)
+{
+	struct ras2_context *ras2_ctx;
+
+	ras2_ctx = dev_get_drvdata(device);
+
+	switch (attr_id) {
+	case scrub_addr_base:
+		return addr_base_write(ras2_ctx, val);
+	case scrub_addr_size:
+		return addr_size_write(ras2_ctx, val);
+	case scrub_enable:
+		return enable_write(ras2_ctx, val);
+	case scrub_enable_background_scrub:
+		return enable_background_scrub_write(ras2_ctx, val);
+	case scrub_rate:
+		return rate_write(ras2_ctx, val);
+	default:
+		return -EOPNOTSUPP;
+	}
+}
+
+/**
+ * ras2_hw_scrub_read_strings() - Read callback for string attributes
+ * @device: Pointer to scrub device
+ * @attr_id: Scrub attribute
+ * @region_id: ID of the memory region
+ * @buf: Pointer to the buffer for copying returned string
+ *
+ * Returns: 0 on success, an error otherwise
+ */
+int ras2_hw_scrub_read_strings(struct device *dev, u32 attr_id,
+			       int region_id, char *buf)
+{
+	struct ras2_context *ras2_ctx;
+
+	ras2_ctx = dev_get_drvdata(dev);
+
+	switch (attr_id) {
+	case scrub_rate_available:
+		return rate_available_read(ras2_ctx, buf);
+	default:
+		return -EOPNOTSUPP;
+	}
+}
diff --git a/include/memory/ras2.h b/include/memory/ras2.h
new file mode 100755
index 000000000000..3db1dce5dd34
--- /dev/null
+++ b/include/memory/ras2.h
@@ -0,0 +1,88 @@ 
+/* SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0 */
+/*
+ * Memory RAS2 driver header file
+ *
+ * Copyright (c) 2024 HiSilicon Limited
+ */
+
+#ifndef _RAS2_H
+#define _RAS2_H
+
+#include <memory/memory-scrub.h>
+
+#define RAS2_MAX_NAME_LENGTH      64
+#define RAS2_MAX_RATE_RANGE_LENGTH      64
+
+/*
+ * Data structures RAS2
+ */
+
+/**
+ * struct ras2_scrub_params- RAS2 scrub parameter data structure.
+ * @addr_base:	[IN] Base address of the address range to be patrol scrubbed.
+ *		[OUT] Base address of the actual address range.
+ * @addr_size:	[IN] Size of the address range to be patrol scrubbed.
+ *		[OUT] Size of the actual address range.
+ * @flags:	[OUT] The platform returns this value in response to
+ *		GET_PATROL_PARAMETERS.
+ *		For RAS2:
+ *		Bit [0]: Will be set if memory scrubber is already
+ *		running for address range specified in “Actual Address Range”.
+ * @rate:	[IN] Requested patrol scrub rate.
+ *		[OUT] Current patrol scrub rate.
+ * @rate_avail:[OUT] Supported patrol rates.
+ */
+struct ras2_scrub_params {
+	u64 addr_base;
+	u64 addr_size;
+	u16 flags;
+	u32 rate;
+	char rate_avail[RAS2_MAX_RATE_RANGE_LENGTH];
+};
+
+enum {
+	RAS2_MEM_SCRUB_PARAM_ADDR_BASE = 0,
+	RAS2_MEM_SCRUB_PARAM_ADDR_SIZE,
+	RAS2_MEM_SCRUB_PARAM_RATE,
+};
+
+/**
+ * struct ras2_hw_scrub_ops - ras2 hw scrub device operations
+ * @enable_scrub: Function to enable/disable RAS2 scrubber.
+ *		Parameters are:
+ *		@ras2_ctx: Pointer to RAS2 context structure.
+ *		@enable: enable/disable RAS2 patrol scrubber.
+ *		The function returns 0 on success or a negative error number.
+ * @enable_background_scrub: Function to enable/disable background scrubbing.
+ *		Parameters are:
+ *		@ras2_ctx: Pointer to RAS2 context structure.
+ *		@enable: enable/disable background patrol scrubbing.
+ *		The function returns 0 on success or a negative error number.
+ * @get_scrub_params:	Read scrubber parameters. Mandatory
+ *		Parameters are:
+ *		@ras2_ctx: Pointer to RAS2 context structure.
+ *		@params: Pointer to scrub params data structure.
+ *		The function returns 0 on success or a negative error number.
+ * @set_scrub_params: Set scrubber parameters. Mandatory.
+ *		Parameters are:
+ *		@ras2_ctx: Pointer to RAS2 context structure.
+ *		@params: Pointer to scrub params data structure.
+ *		@param_type: Scrub parameter type to set.
+ *		The function returns 0 on success or a negative error number.
+ */
+struct ras2_hw_scrub_ops {
+	int (*enable_scrub)(struct ras2_context *ras2_ctx, bool enable);
+	int (*enable_background_scrub)(struct ras2_context *ras2_ctx, bool enable);
+	int (*get_scrub_params)(struct ras2_context *ras2_ctx,
+				struct ras2_scrub_params *params);
+	int (*set_scrub_params)(struct ras2_context *ras2_ctx,
+				struct ras2_scrub_params *params, u8 param_type);
+};
+
+umode_t ras2_hw_scrub_is_visible(struct device *dev, u32 attr_id,
+				 umode_t mode, int region_id);
+int ras2_hw_scrub_read(struct device *dev, u32 attr_id, int region_id, u64 *val);
+int ras2_hw_scrub_write(struct device *dev, u32 attr_id, int region_id, u64 val);
+int ras2_hw_scrub_read_strings(struct device *dev, u32 attr_id,
+			       int region_id, char *buf);
+#endif /* _RAS2_H */