diff options
| author | Ben Widawsky <ben.widawsky@intel.com> | 2021-02-17 07:09:54 +0300 |
|---|---|---|
| committer | Dan Williams <dan.j.williams@intel.com> | 2021-02-17 07:36:38 +0300 |
| commit | 13237183c735f5cba4ae26bc782c613ae0d4e4d3 (patch) | |
| tree | 097c6359d749a8b4729d6fb599bc83612ea21a2b /include/uapi/linux/cxl_mem.h | |
| parent | 583fa5e71caeb79e04e477e9837e2f7fa53b71e4 (diff) | |
| download | linux-13237183c735f5cba4ae26bc782c613ae0d4e4d3.tar.xz | |
cxl/mem: Add a "RAW" send command
The CXL memory device send interface will have a number of supported
commands. The raw command is not such a command. Raw commands allow
userspace to send a specified opcode to the underlying hardware and
bypass all driver checks on the command. The primary use for this
command is to [begrudgingly] allow undocumented vendor specific hardware
commands.
While not the main motivation, it also allows prototyping new hardware
commands without a driver patch and rebuild.
While this all sounds very powerful it comes with a couple of caveats:
1. Bug reports using raw commands will not get the same level of
attention as bug reports using supported commands (via taint).
2. Supported commands will be rejected by the RAW command.
With this comes new debugfs knob to allow full access to your toes with
your weapon of choice.
Signed-off-by: Ben Widawsky <ben.widawsky@intel.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com> (v2)
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Cc: Ariel Sibley <Ariel.Sibley@microchip.com>
Link: https://lore.kernel.org/r/20210217040958.1354670-6-ben.widawsky@intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Diffstat (limited to 'include/uapi/linux/cxl_mem.h')
| -rw-r--r-- | include/uapi/linux/cxl_mem.h | 12 |
1 files changed, 11 insertions, 1 deletions
diff --git a/include/uapi/linux/cxl_mem.h b/include/uapi/linux/cxl_mem.h index 887781dc3b6c..c316028730e7 100644 --- a/include/uapi/linux/cxl_mem.h +++ b/include/uapi/linux/cxl_mem.h @@ -22,6 +22,7 @@ #define CXL_CMDS \ ___C(INVALID, "Invalid Command"), \ ___C(IDENTIFY, "Identify Command"), \ + ___C(RAW, "Raw device command"), \ ___C(MAX, "invalid / last command") #define ___C(a, b) CXL_MEM_COMMAND_ID_##a @@ -115,6 +116,9 @@ struct cxl_mem_query_commands { * @id: The command to send to the memory device. This must be one of the * commands returned by the query command. * @flags: Flags for the command (input). + * @raw: Special fields for raw commands + * @raw.opcode: Opcode passed to hardware when using the RAW command. + * @raw.rsvd: Must be zero. * @rsvd: Must be zero. * @retval: Return value from the memory device (output). * @in: Parameters associated with input payload. @@ -137,7 +141,13 @@ struct cxl_mem_query_commands { struct cxl_send_command { __u32 id; __u32 flags; - __u32 rsvd; + union { + struct { + __u16 opcode; + __u16 rsvd; + } raw; + __u32 rsvd; + }; __u32 retval; struct { |