From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from [140.186.70.92] (port=53572 helo=eggs.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1PeyWE-0005dQ-4X for qemu-devel@nongnu.org; Mon, 17 Jan 2011 18:29:51 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1PeyWB-0006yQ-9W for qemu-devel@nongnu.org; Mon, 17 Jan 2011 18:29:49 -0500 Received: from ra.se.axis.com ([195.60.68.13]:59095) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1PeyWB-0006xs-3z for qemu-devel@nongnu.org; Mon, 17 Jan 2011 18:29:47 -0500 From: edgar.iglesias@gmail.com Date: Tue, 18 Jan 2011 00:29:42 +0100 Message-Id: <1295306982-29629-4-git-send-email-edgar.iglesias@gmail.com> In-Reply-To: <1295306982-29629-1-git-send-email-edgar.iglesias@gmail.com> References: <1295306982-29629-1-git-send-email-edgar.iglesias@gmail.com> Subject: [Qemu-devel] [PATCH 3/3] mips: Expire late timers when reading cp0_count List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: "Edgar E. Iglesias" , aurelien@aurel32.net From: Edgar E. Iglesias When reading cp0_count from a timer with a late trigger that should already have expired, expire it and raise the timer irq. This makes it possible for guest code (e.g, Linux) that first read cp0_count, then compare it with cp0_compare and check for raised timer interrupt lines to run reliably. Signed-off-by: Edgar E. Iglesias --- hw/mips_timer.c | 11 +++++++++-- 1 files changed, 9 insertions(+), 2 deletions(-) diff --git a/hw/mips_timer.c b/hw/mips_timer.c index 8c32087..4e5c0b5 100644 --- a/hw/mips_timer.c +++ b/hw/mips_timer.c @@ -69,9 +69,16 @@ uint32_t cpu_mips_get_count (CPUState *env) if (env->CP0_Cause & (1 << CP0Ca_DC)) { return env->CP0_Count; } else { + uint64_t now; + + now = qemu_get_clock(vm_clock); + if (qemu_timer_expired(env->timer, now)) { + /* The timer has already expired. */ + cpu_mips_timer_expire(env); + } + return env->CP0_Count + - (uint32_t)muldiv64(qemu_get_clock(vm_clock), - TIMER_FREQ, get_ticks_per_sec()); + (uint32_t)muldiv64(now, TIMER_FREQ, get_ticks_per_sec()); } } -- 1.7.2.2