sio: Add test for availability - LPC error tweak

Some components can continue to operate in the face of the SuperIO
controller being unavailable on the LPC bus (specifically, the UART and
boot flag processing). Other components require it present (AST-based
SFC implementations and the AST mailbox). Components in the latter
category can just fail with an errl when they attempt to access the
controller, but for those in the former category we add an isAvailable()
function in the SIO namespace to sidestep dealing with errors.

Specifically, isAvailable() tests for the expected error when the
SuperIO controller is disabled, and returns an errlHndl_t if any other
error occurs. This way true LPC errors are propagated to the caller to
commit as desired.

Change-Id: Ib94ceabfd4f4e9c63c114cfe3db3c954dbb6d6e5
Reviewed-on: http://rchgit01.rchland.ibm.com/gerrit1/67315
Tested-by: Jenkins Server <pfd-jenkins+hostboot@us.ibm.com>
Reviewed-by: ANDREW R. JEFFERY <andrewrj@au1.ibm.com>
Tested-by: Jenkins OP Build CI <op-jenkins+hostboot@us.ibm.com>
Tested-by: Jenkins OP HW <op-hw-jenkins+hostboot@us.ibm.com>
Tested-by: FSP CI Jenkins <fsp-CI-jenkins+hostboot@us.ibm.com>
Reviewed-by: Corey V. Swenson <cswenson@us.ibm.com>
Reviewed-by: William G. Hoffa <wghoffa@us.ibm.com>

1 files changed, 13 insertions, 0 deletions

diff --git a/src/usr/console/ast2400.C b/src/usr/console/ast2400.C
index 1990baf49..213ae789e 100644
--- a/src/usr/console/ast2400.C
+++ b/src/usr/console/ast2400.C
@@ -297,6 +297,18 @@ namespace CONSOLE
 
             do
             {
+                bool haveSio;
+                l_err = SIO::isAvailable(haveSio);
+                if (l_err) { break; }
+
+                if (!haveSio)
+                {
+                    // SIO may have been disabled by the BMC, in which case
+                    // assume the UART is already set up.
+                    Uart::initialize();
+                    break;
+                }
+
                 //  verify the boot flags version from register 0x28
                 l_err = deviceOp( DeviceFW::READ,
                                   TARGETING::MASTER_PROCESSOR_CHIP_TARGET_SENTINEL,
@@ -304,6 +316,7 @@ namespace CONSOLE
                                   l_len,
                                   DEVICE_SIO_ADDRESS(SIO::SUART1, 0x28));
                 if (l_err) { break; }
+
                 // is it the version we expected?
                 if( expected_version == this_version )
                 {