From: Matthew Gerlach <[email protected]>
Add documentation describing the extensions provided by Version
1 of the Device Feature Header (DFHv1).
Signed-off-by: Matthew Gerlach <[email protected]>
Reviewed-by: Ilpo Järvinen <[email protected]>
---
v7: shorten long lines and wording suggestions by [email protected]
v6: no change
v5: use nested list for field descriptions
clean up prose
add reviewed-by and comments from Ilpo Järvinen
v4: Remove marketing speak and separate v0 and v1 descriptions.
Fix errors reported by "make htmldocs".
v3: no change
v2: s/GUILD/GUID/
add picture
---
Documentation/fpga/dfl.rst | 112 +++++++++++++++++++++++++++++++++++++
1 file changed, 112 insertions(+)
diff --git a/Documentation/fpga/dfl.rst b/Documentation/fpga/dfl.rst
index 15b670926084..42fe7ff2b86a 100644
--- a/Documentation/fpga/dfl.rst
+++ b/Documentation/fpga/dfl.rst
@@ -561,6 +561,118 @@ new DFL feature via UIO direct access, its feature id should be added to the
driver's id_table.
+Device Feature Header - Version 0
+===========================================
+Version 0 (DFHv0) is the original version of the Device Feature Header.
+The format of DFHv0 is shown below::
+
+ +-----------------------------------------------------------------------+
+ |63 Type 60|59 DFH VER 52|51 Rsvd 41|40 EOL|39 Next 16|15 VER 12|11 ID 0| 0x00
+ +-----------------------------------------------------------------------+
+ |63 GUID_L 0| 0x08
+ +-----------------------------------------------------------------------+
+ |63 GUID_H 0| 0x10
+ +-----------------------------------------------------------------------+
+
+- Offset 0x00
+
+ * Type - The type of DFH (e.g. FME, AFU, or private feature).
+ * DFH VER - The version of the DFH.
+ * Rsvd - Currently unused.
+ * EOL - Set if the DFH is the end of the Device Feature List (DFL).
+ * Next - The offset of the next DFH in the DFL from the DFH start.
+ If EOL is set, Next is the size of MMIO of the last feature in the list.
+ * ID - The feature ID if Type is private feature.
+
+- Offset 0x08
+
+ * GUID_L - Least significant 64 bits of a 128-bit Globally Unique Identifier
+ (present only if Type is FME or AFU).
+
+- Offset 0x10
+
+ * GUID_H - Most significant 64 bits of a 128-bit Globally Unique Identifier
+ (present only if Type is FME or AFU).
+
+
+Device Feature Header - Version 1
+===========================================
+Version 1 (DFHv1) of the Device Feature Header adds the following functionality:
+
+* Provides a standardized mechanism for features to describe
+ parameters/capabilities to software.
+* Standardize the use of a GUID for all DFHv1 types.
+* Decouples the DFH location from the register space of the feature itself.
+
+The format of Version 1 of the Device Feature Header (DFH) is shown below::
+
+ +-----------------------------------------------------------------------+
+ |63 Type 60|59 DFH VER 52|51 Rsvd 41|40 EOL|39 Next 16|15 VER 12|11 ID 0| 0x00
+ +-----------------------------------------------------------------------+
+ |63 GUID_L 0| 0x08
+ +-----------------------------------------------------------------------+
+ |63 GUID_H 0| 0x10
+ +-----------------------------------------------------------------------+
+ |63 Reg Address/Offset 1| Rel 0| 0x18
+ +-----------------------------------------------------------------------+
+ |63 Reg Size 32|Params 31|30 Group 16|15 Instance 0| 0x20
+ +-----------------------------------------------------------------------+
+ |63 Next 35|34RSV33|EOP32|31 Param Version 16|15 Param ID 0| 0x28
+ +-----------------------------------------------------------------------+
+ |63 Parameter Data 0| 0x30
+ +-----------------------------------------------------------------------+
+
+ ...
+
+ +-----------------------------------------------------------------------+
+ |63 Next 35|34RSV33|EOP32|31 Param Version 16|15 Param ID 0|
+ +-----------------------------------------------------------------------+
+ |63 Parameter Data 0|
+ +-----------------------------------------------------------------------+
+
+- Offset 0x00
+
+ * Type - The type of DFH (e.g. FME, AFU, or private feature).
+ * DFH VER - The version of the DFH.
+ * Rsvd - Currently unused.
+ * EOL - Set if the DFH is the end of the Device Feature List (DFL).
+ * Next - The offset of the next DFH in the DFL from the DFH start.
+ If EOL is set, Next is the size of MMIO of the last feature in the list.
+ * ID - The feature ID if Type is private feature.
+
+- Offset 0x08
+
+ * GUID_L - Least significant 64 bits of a 128-bit Globally Unique Identifier.
+
+- Offset 0x10
+
+ * GUID_H - Most significant 64 bits of a 128-bit Globally Unique Identifier.
+
+- Offset 0x18
+
+ * Reg Address/Offset - If Rel bit is set, then the value is the high 63 bits
+ of a 16-bit aligned absolute address of the feature's registers. Otherwise
+ the value is the offset from the start of the DFH of the feature's registers.
+
+- Offset 0x20
+
+ * Reg Size - Size of feature's register set in bytes.
+ * Params - Set if DFH has a list of parameter blocks.
+ * Group - Id of group if feature is part of a group.
+ * Instance - Id of feature instance within a group.
+
+- Offset 0x28 if feature has parameters
+
+ * Next - Offset to the next parameter block in 8 byte words. If EOP set,
+ size in 8 byte words of last parameter.
+ * Param Version - Version of Param ID.
+ * Param ID - ID of parameter.
+
+- Offset 0x30
+
+ * Parameter Data - Parameter data whose size and format is defined by
+ version and ID of the parameter.
+
Open discussion
===============
FME driver exports one ioctl (DFL_FPGA_FME_PORT_PR) for partial reconfiguration
--
2.25.1
On Tue, Dec 20, 2022 at 08:36:49AM -0800, [email protected] wrote:
> From: Matthew Gerlach <[email protected]>
>
> Add documentation describing the extensions provided by Version
> 1 of the Device Feature Header (DFHv1).
...
> +Device Feature Header - Version 0
> +===========================================
Shouldn't this be the same length as the title itself?
Have you run make htmldocs and kernel doc validator on
this file after your change? Also you can use rst2pdf
to see PDF rendering.
Same to the other title.
--
With Best Regards,
Andy Shevchenko
On Tue, 20 Dec 2022, Andy Shevchenko wrote:
> On Tue, Dec 20, 2022 at 08:36:49AM -0800, [email protected] wrote:
>> From: Matthew Gerlach <[email protected]>
>>
>> Add documentation describing the extensions provided by Version
>> 1 of the Device Feature Header (DFHv1).
>
> ...
>
>> +Device Feature Header - Version 0
>> +===========================================
>
> Shouldn't this be the same length as the title itself?
> Have you run make htmldocs and kernel doc validator on
> this file after your change? Also you can use rst2pdf
> to see PDF rendering.
Yes, it should be the same as the title itself. I will change it
accordingly. I ran "make htmldocs" and rst2pdf, and resulting html and
pdf looked fine.
Thanks for the review,
Matthew Gerlach
>
> Same to the other title.
>
> --
> With Best Regards,
> Andy Shevchenko
>
>
>