ntb_hw_switchtec: Allow using Switchtec NTB in multi-partition setups

Allow using Switchtec NTB in setups that have more than two partitions.
Note: this does not enable having multi-host communication, it only
allows for a single NTB link between two hosts in a network that might
have more than two.

Use following logic to determine the NT peer partition:

1) If there are 2 partitions, and the target vector is set in
   the Switchtec configuration, use the partition specified in target
   vector.
2) If there are 2 partitions and target vector is unset
   use the only other partition as specified in the NT EP map.
3) If there are more than 2 partitions and target vector is set
   use the other partition specified in target vector.
4) If there are more than 2 partitions and target vector is unset,
   this is invalid and report an error.

Signed-off-by: Kelvin Cao <kelvin.cao@microsemi.com>
[logang@deltatee.com: commit message fleshed out]
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Jon Mason <jdmason@kudzu.us>
This commit is contained in:
Kelvin Cao 2017-11-29 10:55:24 -07:00 committed by Jon Mason
parent 2dd0f6a64a
commit 3df54c870f
2 changed files with 56 additions and 9 deletions

View file

@ -168,6 +168,14 @@ struct ntb_info_regs {
u16 reserved1;
u64 ep_map;
u16 requester_id;
u16 reserved2;
u32 reserved3[4];
struct nt_partition_info {
u32 xlink_enabled;
u32 target_part_low;
u32 target_part_high;
u32 reserved;
} ntp_info[48];
} __packed;
struct part_cfg_regs {