powerpc/powernv: Properly drop characters if console is closed

Submitted by Benjamin Herrenschmidt on May 8, 2013, 4:15 a.m.

Details

Message ID 1367986524.25488.115.camel@pasglop
State Accepted, archived
Commit 1de1455f33709a8afd8d41d26d09739a1148105b
Headers show

Commit Message

Benjamin Herrenschmidt May 8, 2013, 4:15 a.m.
If the firmware returns an error such as "closed" (or hardware
error), we should drop characters.

Currently we only do that when a firmware compatible with OPAL v2
APIs is detected, in the code that calls opal_console_write_buffer_space(),
which didn't exist with OPAL v1 (or didn't work).

However, when enabling early debug consoles, the flag indicating
that v2 is supported isn't set yet, causing us, in case of errors
or closed console, to spin forever.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
---
 arch/powerpc/platforms/powernv/opal.c |    7 +++++++
 1 file changed, 7 insertions(+)

Patch hide | download patch | download mbox

diff --git a/arch/powerpc/platforms/powernv/opal.c b/arch/powerpc/platforms/powernv/opal.c
index ade4463..12d9846 100644
--- a/arch/powerpc/platforms/powernv/opal.c
+++ b/arch/powerpc/platforms/powernv/opal.c
@@ -144,6 +144,13 @@  int opal_put_chars(uint32_t vtermno, const char *data, int total_len)
 				rc == OPAL_BUSY_EVENT || rc == OPAL_SUCCESS)) {
 		len = total_len;
 		rc = opal_console_write(vtermno, &len, data);
+
+		/* Closed or other error drop */
+		if (rc != OPAL_SUCCESS && rc != OPAL_BUSY &&
+		    rc != OPAL_BUSY_EVENT) {
+			written = total_len;
+			break;
+		}
 		if (rc == OPAL_SUCCESS) {
 			total_len -= len;
 			data += len;