diff mbox series

[v4,1/4] fpga: dfl: expose feature revision from struct dfl_device

Message ID 20210705101645.2040106-2-martin@geanix.com (mailing list archive)
State New, archived
Headers show
Series fpga/mfd/hwmon: Initial support for Silicom N5010 PAC | expand

Commit Message

Martin Hundebøll July 5, 2021, 10:16 a.m. UTC 
From: Martin Hundebøll <mhu@silicom.dk>

DFL device drivers have a common need for checking feature revision
information from the DFL header, as well as other common DFL information
like the already exposed feature id and type.

This patch exposes the feature revision information directly via the DFL
device data structure.

Since the DFL core code has already read the DFL header, this this patch
saves additional mmio reads from DFL device drivers too.

Signed-off-by: Martin Hundebøll <mhu@silicom.dk>
Acked-by: Wu Hao <hao.wu@intel.com>
Acked-by: Matthew Gerlach <matthew.gerlach@linux.intel.com>
---

Changes since v3:
 * Added Hao's Acked-by
 * Added Matthew's Acked-by

Changes since v2:
 * Reworded commit message as per Hao's suggestion

Changes since v1:
 * This patch replaces the previous patch 2 and exposes the feature
   revision through struct dfl_device instead of a helper reading from
   io-mem

 drivers/fpga/dfl.c  | 27 +++++++++++++++++----------
 drivers/fpga/dfl.h  |  1 +
 include/linux/dfl.h |  1 +
 3 files changed, 19 insertions(+), 10 deletions(-)

Comments

Tom Rix July 6, 2021, 2:10 p.m. UTC | #1 
On 7/5/21 3:16 AM, Martin Hundebøll wrote:
> From: Martin Hundebøll <mhu@silicom.dk>
>
> DFL device drivers have a common need for checking feature revision
> information from the DFL header, as well as other common DFL information
> like the already exposed feature id and type.
>
> This patch exposes the feature revision information directly via the DFL
> device data structure.
>
> Since the DFL core code has already read the DFL header, this this patch
> saves additional mmio reads from DFL device drivers too.
>
> Signed-off-by: Martin Hundebøll <mhu@silicom.dk>
> Acked-by: Wu Hao <hao.wu@intel.com>
> Acked-by: Matthew Gerlach <matthew.gerlach@linux.intel.com>
> ---
>
> Changes since v3:
>   * Added Hao's Acked-by
>   * Added Matthew's Acked-by
>
> Changes since v2:
>   * Reworded commit message as per Hao's suggestion
>
> Changes since v1:
>   * This patch replaces the previous patch 2 and exposes the feature
>     revision through struct dfl_device instead of a helper reading from
>     io-mem
>
>   drivers/fpga/dfl.c  | 27 +++++++++++++++++----------
>   drivers/fpga/dfl.h  |  1 +
>   include/linux/dfl.h |  1 +
>   3 files changed, 19 insertions(+), 10 deletions(-)
>
> diff --git a/drivers/fpga/dfl.c b/drivers/fpga/dfl.c
> index 511b20ff35a3..9381c579d1cd 100644
> --- a/drivers/fpga/dfl.c
> +++ b/drivers/fpga/dfl.c
> @@ -381,6 +381,7 @@ dfl_dev_add(struct dfl_feature_platform_data *pdata,
>   
>   	ddev->type = feature_dev_id_type(pdev);
>   	ddev->feature_id = feature->id;
> +	ddev->revision = feature->revision;
>   	ddev->cdev = pdata->dfl_cdev;
>   
>   	/* add mmio resource */
> @@ -717,6 +718,7 @@ struct build_feature_devs_info {
>    */
>   struct dfl_feature_info {
>   	u16 fid;
> +	u8 rev;

In other places 'revision' is the element name.

For consistency, change rev to revision

>   	struct resource mmio_res;
>   	void __iomem *ioaddr;
>   	struct list_head node;
> @@ -796,6 +798,7 @@ static int build_info_commit_dev(struct build_feature_devs_info *binfo)
>   		/* save resource information for each feature */
>   		feature->dev = fdev;
>   		feature->id = finfo->fid;
> +		feature->revision = finfo->rev;
>   
>   		/*
>   		 * the FIU header feature has some fundamental functions (sriov
> @@ -910,19 +913,17 @@ static void build_info_free(struct build_feature_devs_info *binfo)
>   	devm_kfree(binfo->dev, binfo);
>   }
>   
> -static inline u32 feature_size(void __iomem *start)
> +static inline u32 feature_size(u64 value)

The return type should match its use in create_feature_instance 
'resource_size_t'

change u32 to resource_size_t

Tom

>   {
> -	u64 v = readq(start + DFH);
> -	u32 ofst = FIELD_GET(DFH_NEXT_HDR_OFST, v);
> +	u32 ofst = FIELD_GET(DFH_NEXT_HDR_OFST, value);
>   	/* workaround for private features with invalid size, use 4K instead */
>   	return ofst ? ofst : 4096;
>   }
>   
> -static u16 feature_id(void __iomem *start)
> +static u16 feature_id(u64 value)
>   {
> -	u64 v = readq(start + DFH);
> -	u16 id = FIELD_GET(DFH_ID, v);
> -	u8 type = FIELD_GET(DFH_TYPE, v);
> +	u16 id = FIELD_GET(DFH_ID, value);
> +	u8 type = FIELD_GET(DFH_TYPE, value);
>   
>   	if (type == DFH_TYPE_FIU)
>   		return FEATURE_ID_FIU_HEADER;
> @@ -1021,10 +1022,15 @@ create_feature_instance(struct build_feature_devs_info *binfo,
>   	unsigned int irq_base, nr_irqs;
>   	struct dfl_feature_info *finfo;
>   	int ret;
> +	u8 rev;
> +	u64 v;
> +
> +	v = readq(binfo->ioaddr + ofst);
> +	rev = FIELD_GET(DFH_REVISION, v);
>   
>   	/* read feature size and id if inputs are invalid */
> -	size = size ? size : feature_size(binfo->ioaddr + ofst);
> -	fid = fid ? fid : feature_id(binfo->ioaddr + ofst);
> +	size = size ? size : feature_size(v);
> +	fid = fid ? fid : feature_id(v);
>   
>   	if (binfo->len - ofst < size)
>   		return -EINVAL;
> @@ -1038,6 +1044,7 @@ create_feature_instance(struct build_feature_devs_info *binfo,
>   		return -ENOMEM;
>   
>   	finfo->fid = fid;
> +	finfo->rev = rev;
>   	finfo->mmio_res.start = binfo->start + ofst;
>   	finfo->mmio_res.end = finfo->mmio_res.start + size - 1;
>   	finfo->mmio_res.flags = IORESOURCE_MEM;
> @@ -1166,7 +1173,7 @@ static int parse_feature_private(struct build_feature_devs_info *binfo,
>   {
>   	if (!is_feature_dev_detected(binfo)) {
>   		dev_err(binfo->dev, "the private feature 0x%x does not belong to any AFU.\n",
> -			feature_id(binfo->ioaddr + ofst));
> +			feature_id(readq(binfo->ioaddr + ofst)));
>   		return -EINVAL;
>   	}
>   
> diff --git a/drivers/fpga/dfl.h b/drivers/fpga/dfl.h
> index 2b82c96ba56c..422157cfd742 100644
> --- a/drivers/fpga/dfl.h
> +++ b/drivers/fpga/dfl.h
> @@ -243,6 +243,7 @@ struct dfl_feature_irq_ctx {
>   struct dfl_feature {
>   	struct platform_device *dev;
>   	u16 id;
> +	u8 revision;
>   	int resource_index;
>   	void __iomem *ioaddr;
>   	struct dfl_feature_irq_ctx *irq_ctx;
> diff --git a/include/linux/dfl.h b/include/linux/dfl.h
> index 6cc10982351a..431636a0dc78 100644
> --- a/include/linux/dfl.h
> +++ b/include/linux/dfl.h
> @@ -38,6 +38,7 @@ struct dfl_device {
>   	int id;
>   	u16 type;
>   	u16 feature_id;
> +	u8 revision;
>   	struct resource mmio_res;
>   	int *irqs;
>   	unsigned int num_irqs;
Martin Hundebøll July 14, 2021, 11:14 a.m. UTC | #2 
On 06/07/2021 16.10, Tom Rix wrote:
>> diff --git a/drivers/fpga/dfl.c b/drivers/fpga/dfl.c
>> index 511b20ff35a3..9381c579d1cd 100644
>> --- a/drivers/fpga/dfl.c
>> +++ b/drivers/fpga/dfl.c
>> @@ -381,6 +381,7 @@ dfl_dev_add(struct dfl_feature_platform_data *pdata,
>>       ddev->type = feature_dev_id_type(pdev);
>>       ddev->feature_id = feature->id;
>> +    ddev->revision = feature->revision;
>>       ddev->cdev = pdata->dfl_cdev;
>>       /* add mmio resource */
>> @@ -717,6 +718,7 @@ struct build_feature_devs_info {
>>    */
>>   struct dfl_feature_info {
>>       u16 fid;
>> +    u8 rev;
> 
> In other places 'revision' is the element name.
> 
> For consistency, change rev to revision

So is fid vs. feature. I deliberately chose 'rev' to be consistent
with other elements in struct dfl_feature_info.

// Martin
Tom Rix July 14, 2021, 2:30 p.m. UTC | #3 
On 7/14/21 4:14 AM, Martin Hundebøll wrote:
>
>
> On 06/07/2021 16.10, Tom Rix wrote:
>>> diff --git a/drivers/fpga/dfl.c b/drivers/fpga/dfl.c
>>> index 511b20ff35a3..9381c579d1cd 100644
>>> --- a/drivers/fpga/dfl.c
>>> +++ b/drivers/fpga/dfl.c
>>> @@ -381,6 +381,7 @@ dfl_dev_add(struct dfl_feature_platform_data 
>>> *pdata,
>>>       ddev->type = feature_dev_id_type(pdev);
>>>       ddev->feature_id = feature->id;
>>> +    ddev->revision = feature->revision;
>>>       ddev->cdev = pdata->dfl_cdev;
>>>       /* add mmio resource */
>>> @@ -717,6 +718,7 @@ struct build_feature_devs_info {
>>>    */
>>>   struct dfl_feature_info {
>>>       u16 fid;
>>> +    u8 rev;
>>
>> In other places 'revision' is the element name.
>>
>> For consistency, change rev to revision
>
> So is fid vs. feature. I deliberately chose 'rev' to be consistent
> with other elements in struct dfl_feature_info.

Consistence for revision is important because we want to make it easy 
for folks using grep to search for one string not several.

fid vs feature_id is a problem, but one you do not need to solve.

Tom


>
> // Martin
>
diff mbox series

Patch

diff --git a/drivers/fpga/dfl.c b/drivers/fpga/dfl.c
index 511b20ff35a3..9381c579d1cd 100644
--- a/drivers/fpga/dfl.c
+++ b/drivers/fpga/dfl.c
@@ -381,6 +381,7 @@  dfl_dev_add(struct dfl_feature_platform_data *pdata,
 
 	ddev->type = feature_dev_id_type(pdev);
 	ddev->feature_id = feature->id;
+	ddev->revision = feature->revision;
 	ddev->cdev = pdata->dfl_cdev;
 
 	/* add mmio resource */
@@ -717,6 +718,7 @@  struct build_feature_devs_info {
  */
 struct dfl_feature_info {
 	u16 fid;
+	u8 rev;
 	struct resource mmio_res;
 	void __iomem *ioaddr;
 	struct list_head node;
@@ -796,6 +798,7 @@  static int build_info_commit_dev(struct build_feature_devs_info *binfo)
 		/* save resource information for each feature */
 		feature->dev = fdev;
 		feature->id = finfo->fid;
+		feature->revision = finfo->rev;
 
 		/*
 		 * the FIU header feature has some fundamental functions (sriov
@@ -910,19 +913,17 @@  static void build_info_free(struct build_feature_devs_info *binfo)
 	devm_kfree(binfo->dev, binfo);
 }
 
-static inline u32 feature_size(void __iomem *start)
+static inline u32 feature_size(u64 value)
 {
-	u64 v = readq(start + DFH);
-	u32 ofst = FIELD_GET(DFH_NEXT_HDR_OFST, v);
+	u32 ofst = FIELD_GET(DFH_NEXT_HDR_OFST, value);
 	/* workaround for private features with invalid size, use 4K instead */
 	return ofst ? ofst : 4096;
 }
 
-static u16 feature_id(void __iomem *start)
+static u16 feature_id(u64 value)
 {
-	u64 v = readq(start + DFH);
-	u16 id = FIELD_GET(DFH_ID, v);
-	u8 type = FIELD_GET(DFH_TYPE, v);
+	u16 id = FIELD_GET(DFH_ID, value);
+	u8 type = FIELD_GET(DFH_TYPE, value);
 
 	if (type == DFH_TYPE_FIU)
 		return FEATURE_ID_FIU_HEADER;
@@ -1021,10 +1022,15 @@  create_feature_instance(struct build_feature_devs_info *binfo,
 	unsigned int irq_base, nr_irqs;
 	struct dfl_feature_info *finfo;
 	int ret;
+	u8 rev;
+	u64 v;
+
+	v = readq(binfo->ioaddr + ofst);
+	rev = FIELD_GET(DFH_REVISION, v);
 
 	/* read feature size and id if inputs are invalid */
-	size = size ? size : feature_size(binfo->ioaddr + ofst);
-	fid = fid ? fid : feature_id(binfo->ioaddr + ofst);
+	size = size ? size : feature_size(v);
+	fid = fid ? fid : feature_id(v);
 
 	if (binfo->len - ofst < size)
 		return -EINVAL;
@@ -1038,6 +1044,7 @@  create_feature_instance(struct build_feature_devs_info *binfo,
 		return -ENOMEM;
 
 	finfo->fid = fid;
+	finfo->rev = rev;
 	finfo->mmio_res.start = binfo->start + ofst;
 	finfo->mmio_res.end = finfo->mmio_res.start + size - 1;
 	finfo->mmio_res.flags = IORESOURCE_MEM;
@@ -1166,7 +1173,7 @@  static int parse_feature_private(struct build_feature_devs_info *binfo,
 {
 	if (!is_feature_dev_detected(binfo)) {
 		dev_err(binfo->dev, "the private feature 0x%x does not belong to any AFU.\n",
-			feature_id(binfo->ioaddr + ofst));
+			feature_id(readq(binfo->ioaddr + ofst)));
 		return -EINVAL;
 	}
 
diff --git a/drivers/fpga/dfl.h b/drivers/fpga/dfl.h
index 2b82c96ba56c..422157cfd742 100644
--- a/drivers/fpga/dfl.h
+++ b/drivers/fpga/dfl.h
@@ -243,6 +243,7 @@  struct dfl_feature_irq_ctx {
 struct dfl_feature {
 	struct platform_device *dev;
 	u16 id;
+	u8 revision;
 	int resource_index;
 	void __iomem *ioaddr;
 	struct dfl_feature_irq_ctx *irq_ctx;
diff --git a/include/linux/dfl.h b/include/linux/dfl.h
index 6cc10982351a..431636a0dc78 100644
--- a/include/linux/dfl.h
+++ b/include/linux/dfl.h
@@ -38,6 +38,7 @@  struct dfl_device {
 	int id;
 	u16 type;
 	u16 feature_id;
+	u8 revision;
 	struct resource mmio_res;
 	int *irqs;
 	unsigned int num_irqs;