From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([208.118.235.92]:38712) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Tiusi-0001FA-95 for qemu-devel@nongnu.org; Wed, 12 Dec 2012 17:34:25 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Tiush-0006aS-63 for qemu-devel@nongnu.org; Wed, 12 Dec 2012 17:34:24 -0500 Received: from mail-ea0-f173.google.com ([209.85.215.173]:57316) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Tiusg-0006aH-Vs for qemu-devel@nongnu.org; Wed, 12 Dec 2012 17:34:23 -0500 Received: by mail-ea0-f173.google.com with SMTP id i13so447355eaa.4 for ; Wed, 12 Dec 2012 14:34:22 -0800 (PST) Message-ID: <50C90645.50102@gmail.com> Date: Wed, 12 Dec 2012 23:33:41 +0100 From: Antoine Mathys MIME-Version: 1.0 References: <50C9041A.8020202@gmail.com> In-Reply-To: <50C9041A.8020202@gmail.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH v3 5/6] hw/ds1338.c: Implement support for the control register. List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: Peter Maydell , paul@codesourcery.com Signed-off-by: Antoine Mathys --- hw/ds1338.c | 17 +++++++++++++---- 1 file changed, 13 insertions(+), 4 deletions(-) diff --git a/hw/ds1338.c b/hw/ds1338.c index d2f52fc..94a2f54 100644 --- a/hw/ds1338.c +++ b/hw/ds1338.c @@ -125,7 +125,8 @@ static int ds1338_send(I2CSlave *i2c, uint8_t data) s->addr_byte = false; return 0; } - if (s->ptr < 8) { + if (s->ptr < 7) { + /* Time register. */ struct tm now; qemu_get_timedate(&now, s->offset); switch(s->ptr) { @@ -162,11 +163,19 @@ static int ds1338_send(I2CSlave *i2c, uint8_t data) case 6: now.tm_year = from_bcd(data) + 100; break; - case 7: - /* Control register. Currently ignored. */ - break; } s->offset = qemu_timedate_diff(&now); + } else if (s->ptr == 7) { + /* Control register. */ + + /* Ensure bits 2, 3 and 6 will read back as zero. */ + data &= 0xB3; + + /* Attempting to write the OSF flag to logic 1 leaves the + value unchanged. */ + data = (data & ~CTRL_OSF) | (data & s->nvram[s->ptr] & CTRL_OSF); + + s->nvram[s->ptr] = data; } else { s->nvram[s->ptr] = data; } -- 1.7.10.4