[PATCH v9 1/4] Documentation: fpga: dfl: Add documentation for DFHv1

From: matthew . gerlach
Date: Wed Jan 04 2023 - 18:22:48 EST


From: Matthew Gerlach <matthew.gerlach@xxxxxxxxxxxxxxx>

Add documentation describing the extensions provided by Version
1 of the Device Feature Header (DFHv1).

Signed-off-by: Matthew Gerlach <matthew.gerlach@xxxxxxxxxxxxxxx>
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@xxxxxxxxxxxxxxx>
---
v9: move DFH definitions to after the Overview
fix name of feature revision field
clarify next field in DFH

v8: fix section titles

v7: shorten long lines and wording suggestions by bagasdotme@xxxxxxxxx

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 | 117 +++++++++++++++++++++++++++++++++++++
1 file changed, 117 insertions(+)

diff --git a/Documentation/fpga/dfl.rst b/Documentation/fpga/dfl.rst
index 15b670926084..7e015249785b 100644
--- a/Documentation/fpga/dfl.rst
+++ b/Documentation/fpga/dfl.rst
@@ -75,6 +75,123 @@ convenient for software to locate each feature by walking through this list,
and can be implemented in register regions of any FPGA device.


+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 REV 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 in bytes of the next DFH in the DFL from the DFH start,
+ and the start of a DFH must be aligned to an 8 byte boundary.
+ If EOL is set, Next is the size of MMIO of the last feature in the list.
+ * REV - The revision of the feature associated with this header.
+ * 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 REV 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 in bytes of the next DFH in the DFL from the DFH start,
+ and the start of a DFH must be aligned to an 8 byte boundary.
+ If EOL is set, Next is the size of MMIO of the last feature in the list.
+ * REV - The revision of the feature associated with this header.
+ * 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.
+
+
FIU - FME (FPGA Management Engine)
==================================
The FPGA Management Engine performs reconfiguration and other infrastructure
--
2.25.1