LDC changes for porting VCC driver into upstream kernel

This series of patches is part of an effort to add VCC (Virtual Channel Concentrator) and VDS (Virtual Disk Server) support to Linux.

VCC & VDS enable the virtualization of serial console and storage respectively, on SPARC processors. VCC provides access to the guest domain's serial console. VDS provides the ability to allocate storage to the guest domain.

Both VCC & VDS depend on some core functionalities in the linux kernel for SPARC. The functionalities include LDC (Logical Domain Channels), MDESC (Machine Descriptor) and VIO (Virtual IO protocol). In order for VCC & VDS to be enabled, it requires that these core functionalities support them.

This version 3 of the series addresses the following changes suggested by Dave Miller
Patch 1/5: Removes ldc_enable_hv_intr & ldc_disable_hv_intr APIs

Jag Raman (5):
sparc64: expand LDC interface
sparc64: enhance ldc_abort to print message
sparc64: ensure LDC channel is ready before communication
sparc64: ldc abort during vds iso boot
sparc64: print debug messages when reading from LDC channel

 arch/sparc/include/asm/ldc.h |    6 ++
 arch/sparc/kernel/ldc.c      |  145 +++++++++++++++++++++++++++++------------
 2 files changed, 108 insertions(+), 43 deletions(-)

Can you please sned pointers to these drivers along to review your changes? In general new exports should go along with their users.

The drivers are planned to be sent out for review 3 or 4 patch series down the line. It wouldn't compile if the driver was sent out right after this patch.

The plan is to gradually add APIs/changes that would satisfy the dependency for the drivers, before they are finally consumed by the drivers.

Would it be alright if these APIs could be defined but not exported until consumed?

From: Jag Raman <[email protected]>
Date: Fri, 26 May 2017 11:51:38 -0400

Yes, but only if you put the drivers up somewhere (even if they currently won't compile) so we can _see_ how these new APIs are used.