diff --git a/drivers/s390/cio/chsc.c b/drivers/s390/cio/chsc.c index 9f0ea6cb6922..e3bf885f4a6c 100644 --- a/drivers/s390/cio/chsc.c +++ b/drivers/s390/cio/chsc.c @@ -541,18 +541,27 @@ static void chsc_process_sei_nt0(struct chsc_sei_nt0_area *sei_area) static void chsc_process_event_information(struct chsc_sei *sei, u64 ntsm) { - do { + static int ntsm_unsupported; + + while (true) { memset(sei, 0, sizeof(*sei)); sei->request.length = 0x0010; sei->request.code = 0x000e; - sei->ntsm = ntsm; + if (!ntsm_unsupported) + sei->ntsm = ntsm; if (chsc(sei)) break; if (sei->response.code != 0x0001) { - CIO_CRW_EVENT(2, "chsc: sei failed (rc=%04x)\n", - sei->response.code); + CIO_CRW_EVENT(2, "chsc: sei failed (rc=%04x, ntsm=%llx)\n", + sei->response.code, sei->ntsm); + + if (sei->response.code == 3 && sei->ntsm) { + /* Fallback for old firmware. */ + ntsm_unsupported = 1; + continue; + } break; } @@ -568,7 +577,10 @@ static void chsc_process_event_information(struct chsc_sei *sei, u64 ntsm) CIO_CRW_EVENT(2, "chsc: unhandled nt: %d\n", sei->nt); break; } - } while (sei->u.nt0_area.flags & 0x80); + + if (!(sei->u.nt0_area.flags & 0x80)) + break; + } } /*