From mboxrd@z Thu Jan  1 00:00:00 1970
Received: from eggs.gnu.org ([2001:4830:134:3::10]:42385)
	by lists.gnu.org with esmtp (Exim 4.71)
	(envelope-from <alex.bennee@linaro.org>) id 1YcyHo-0006Li-H5
	for qemu-devel@nongnu.org; Tue, 31 Mar 2015 11:41:08 -0400
Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71)
	(envelope-from <alex.bennee@linaro.org>) id 1YcyHj-0004Ad-Hv
	for qemu-devel@nongnu.org; Tue, 31 Mar 2015 11:41:04 -0400
Received: from static.88-198-71-155.clients.your-server.de
	([88.198.71.155]:54266 helo=socrates.bennee.com)
	by eggs.gnu.org with esmtp (Exim 4.71)
	(envelope-from <alex.bennee@linaro.org>) id 1YcyHj-0004AJ-BV
	for qemu-devel@nongnu.org; Tue, 31 Mar 2015 11:40:59 -0400
From: =?UTF-8?q?Alex=20Benn=C3=A9e?= <alex.bennee@linaro.org>
Date: Tue, 31 Mar 2015 16:40:45 +0100
Message-Id: <1427816446-31586-4-git-send-email-alex.bennee@linaro.org>
In-Reply-To: <1427816446-31586-1-git-send-email-alex.bennee@linaro.org>
References: <1427816446-31586-1-git-send-email-alex.bennee@linaro.org>
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Subject: [Qemu-devel] [PATCH v2 3/4] target-arm: kvm - support for single
	step
List-Id: <qemu-devel.nongnu.org>
List-Unsubscribe: <https://lists.nongnu.org/mailman/options/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=unsubscribe>
List-Archive: <http://lists.nongnu.org/archive/html/qemu-devel>
List-Post: <mailto:qemu-devel@nongnu.org>
List-Help: <mailto:qemu-devel-request@nongnu.org?subject=help>
List-Subscribe: <https://lists.nongnu.org/mailman/listinfo/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=subscribe>
To: qemu-devel@nongnu.org, peter.maydell@linaro.org, christoffer.dall@linaro.org, zhichao.huang@linaro.org
Cc: kvm@vger.kernel.org, marc.zyngier@arm.com, Paolo Bonzini <pbonzini@redhat.com>, =?UTF-8?q?Alex=20Benn=C3=A9e?= <alex.bennee@linaro.org>, kvmarm@lists.cs.columbia.edu, linux-arm-kernel@lists.infradead.org

This adds support for single-step. There isn't much to do on the QEMU
side as after we set-up the request for single step via the debug ioctl
it is all handled within the kernel.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>

---
v2
  - convert to using HSR_EC

diff --git a/target-arm/kvm.c b/target-arm/kvm.c
index 290c1fe..ae0f8b2 100644
--- a/target-arm/kvm.c
+++ b/target-arm/kvm.c
@@ -475,6 +475,7 @@ void kvm_arch_post_run(CPUState *cs, struct kvm_run *run)
 */
 
 #define HSR_EC_SHIFT            26
+#define HSR_EC_SOFT_STEP        0x32
 #define HSR_EC_SW_BKPT          0x3c
 
 static int kvm_handle_debug(CPUState *cs, struct kvm_run *run)
@@ -483,6 +484,13 @@ static int kvm_handle_debug(CPUState *cs, struct kvm_run *run)
     int hsr_ec = arch_info->hsr >> HSR_EC_SHIFT;
 
     switch (hsr_ec) {
+    case HSR_EC_SOFT_STEP:
+        if (cs->singlestep_enabled) {
+            return true;
+        } else {
+            error_report("Came out of SINGLE STEP when not enabled");
+        }
+        break;
     case HSR_EC_SW_BKPT:
         if (kvm_find_sw_breakpoint(cs, arch_info->pc)) {
             return true;
@@ -542,6 +550,9 @@ int kvm_arch_on_sigbus(int code, void *addr)
 
 void kvm_arch_update_guest_debug(CPUState *cs, struct kvm_guest_debug *dbg)
 {
+    if (cs->singlestep_enabled) {
+        dbg->control |= KVM_GUESTDBG_ENABLE | KVM_GUESTDBG_SINGLESTEP;
+    }
     if (kvm_sw_breakpoints_active(cs)) {
         dbg->control |= KVM_GUESTDBG_ENABLE | KVM_GUESTDBG_USE_SW_BP;
     }
-- 
2.3.4