From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pl0-x242.google.com (mail-pl0-x242.google.com [IPv6:2607:f8b0:400e:c01::242]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 40KJfw3jkszDrqP for ; Mon, 9 Apr 2018 15:25:44 +1000 (AEST) Received: by mail-pl0-x242.google.com with SMTP id s10-v6so4482725plp.0 for ; Sun, 08 Apr 2018 22:25:44 -0700 (PDT) From: Nicholas Piggin To: linuxppc-dev@lists.ozlabs.org Cc: Nicholas Piggin , Benjamin Herrenschmidt Subject: [PATCH v2 4/9] powerpc/powernv: OPAL console standardise OPAL_BUSY loops Date: Mon, 9 Apr 2018 15:24:26 +1000 Message-Id: <20180409052431.26405-5-npiggin@gmail.com> In-Reply-To: <20180409052431.26405-1-npiggin@gmail.com> References: <20180409052431.26405-1-npiggin@gmail.com> List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Convert to using the standard delay poll/delay form. The console code: - Did not previously delay or sleep in its busy loop. Cc: Benjamin Herrenschmidt Signed-off-by: Nicholas Piggin --- arch/powerpc/platforms/powernv/opal.c | 38 ++++++++++++++++----------- 1 file changed, 23 insertions(+), 15 deletions(-) diff --git a/arch/powerpc/platforms/powernv/opal.c b/arch/powerpc/platforms/powernv/opal.c index 87d4c0aa7f64..473c8ce14a34 100644 --- a/arch/powerpc/platforms/powernv/opal.c +++ b/arch/powerpc/platforms/powernv/opal.c @@ -378,33 +378,41 @@ int opal_put_chars(uint32_t vtermno, const char *data, int total_len) /* We still try to handle partial completions, though they * should no longer happen. */ - rc = OPAL_BUSY; - while(total_len > 0 && (rc == OPAL_BUSY || - rc == OPAL_BUSY_EVENT || rc == OPAL_SUCCESS)) { + + while (total_len > 0) { olen = cpu_to_be64(total_len); - rc = opal_console_write(vtermno, &olen, data); + + rc = OPAL_BUSY; + while (rc == OPAL_BUSY || rc == OPAL_BUSY_EVENT) { + rc = opal_console_write(vtermno, &olen, data); + if (rc == OPAL_BUSY_EVENT) { + mdelay(OPAL_BUSY_DELAY_MS); + opal_poll_events(NULL); + } else if (rc == OPAL_BUSY) { + mdelay(OPAL_BUSY_DELAY_MS); + } + } + len = be64_to_cpu(olen); /* Closed or other error drop */ - if (rc != OPAL_SUCCESS && rc != OPAL_BUSY && - rc != OPAL_BUSY_EVENT) { - written += total_len; + if (rc != OPAL_SUCCESS) { + written += total_len; /* drop remaining chars */ break; } - if (rc == OPAL_SUCCESS) { - total_len -= len; - data += len; - written += len; - } + + total_len -= len; + data += len; + written += len; + /* This is a bit nasty but we need that for the console to * flush when there aren't any interrupts. We will clean * things a bit later to limit that to synchronous path * such as the kernel console and xmon/udbg */ - do + do { opal_poll_events(&evt); - while(rc == OPAL_SUCCESS && - (be64_to_cpu(evt) & OPAL_EVENT_CONSOLE_OUTPUT)); + } while (be64_to_cpu(evt) & OPAL_EVENT_CONSOLE_OUTPUT); } spin_unlock_irqrestore(&opal_write_lock, flags); return written; -- 2.17.0