[Qemu-devel] [PATCH v10 2/5] intc/gic: Extract some reusable vGIC code

[Pavel Fedin]

These functions are useful also for vGICv3 implementation. Make them accessible
from within other modules.

Actually kvm_dist_get() and kvm_dist_put() could also be made reusable, but
they would require two extra parameters (s->dev_fd and s->num_cpu) as well as
lots of typecasts of 's' to DeviceState * and back to GICState *. This makes
the code very ugly so i decided to stop at this point. I tried also an
approach with making a base class for all possible GICs, but it would contain
only three variables (dev_fd, cpu_num and irq_num), and accessing them through
the rest of the code would be again tedious (either ugly casts or qemu-style
separate object pointer). So i disliked it too.

Signed-off-by: Pavel Fedin <address@hidden>
---
 hw/intc/arm_gic_kvm.c | 42 +++++++++++++++++----------------------
 hw/intc/vgic_common.h | 55 +++++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 73 insertions(+), 24 deletions(-)
 create mode 100644 hw/intc/vgic_common.h

diff --git a/hw/intc/arm_gic_kvm.c b/hw/intc/arm_gic_kvm.c
index e5d0f67..0c71ef8 100644
--- a/hw/intc/arm_gic_kvm.c
+++ b/hw/intc/arm_gic_kvm.c
@@ -23,6 +23,7 @@
 #include "sysemu/kvm.h"
 #include "kvm_arm.h"
 #include "gic_internal.h"
+#include "vgic_common.h"
 
 //#define DEBUG_GIC_KVM
 
@@ -52,7 +53,7 @@ typedef struct KVMARMGICClass {
     void (*parent_reset)(DeviceState *dev);
 } KVMARMGICClass;
 
-static void kvm_arm_gic_set_irq(void *opaque, int irq, int level)
+void kvm_arm_gic_set_irq(uint32_t num_irq, int irq, int level)
 {
     /* Meaning of the 'irq' parameter:
      *  [0..N-1] : external interrupts
@@ -63,10 +64,9 @@ static void kvm_arm_gic_set_irq(void *opaque, int irq, int 
level)
      * has separate fields in the irq number for type,
      * CPU number and interrupt number.
      */
-    GICState *s = (GICState *)opaque;
     int kvm_irq, irqtype, cpu;
 
-    if (irq < (s->num_irq - GIC_INTERNAL)) {
+    if (irq < (num_irq - GIC_INTERNAL)) {
         /* External interrupt. The kernel numbers these like the GIC
          * hardware, with external interrupt IDs starting after the
          * internal ones.
@@ -77,7 +77,7 @@ static void kvm_arm_gic_set_irq(void *opaque, int irq, int 
level)
     } else {
         /* Internal interrupt: decode into (cpu, interrupt id) */
         irqtype = KVM_ARM_IRQ_TYPE_PPI;
-        irq -= (s->num_irq - GIC_INTERNAL);
+        irq -= (num_irq - GIC_INTERNAL);
         cpu = irq / GIC_INTERNAL;
         irq %= GIC_INTERNAL;
     }
@@ -87,6 +87,13 @@ static void kvm_arm_gic_set_irq(void *opaque, int irq, int 
level)
     kvm_set_irq(kvm_state, kvm_irq, !!level);
 }
 
+static void kvm_arm_gicv2_set_irq(void *opaque, int irq, int level)
+{
+    GICState *s = (GICState *)opaque;
+
+    kvm_arm_gic_set_irq(s->num_irq, irq, level);
+}
+
 static bool kvm_arm_gic_can_save_restore(GICState *s)
 {
     return s->dev_fd >= 0;
@@ -107,8 +114,8 @@ static bool kvm_gic_supports_attr(GICState *s, int group, 
int attrnum)
     return kvm_device_ioctl(s->dev_fd, KVM_HAS_DEVICE_ATTR, &attr) == 0;
 }
 
-static void kvm_gic_access(GICState *s, int group, int offset,
-                                   int cpu, uint32_t *val, bool write)
+void kvm_gic_access(int dev_fd, int group, int offset,
+                    int cpu, void *val, bool write)
 {
     struct kvm_device_attr attr;
     int type;
@@ -130,7 +137,7 @@ static void kvm_gic_access(GICState *s, int group, int 
offset,
         type = KVM_GET_DEVICE_ATTR;
     }
 
-    err = kvm_device_ioctl(s->dev_fd, type, &attr);
+    err = kvm_device_ioctl(dev_fd, type, &attr);
     if (err < 0) {
         fprintf(stderr, "KVM_{SET/GET}_DEVICE_ATTR failed: %s\n",
                 strerror(-err));
@@ -138,20 +145,6 @@ static void kvm_gic_access(GICState *s, int group, int 
offset,
     }
 }
 
-static void kvm_gicd_access(GICState *s, int offset, int cpu,
-                            uint32_t *val, bool write)
-{
-    kvm_gic_access(s, KVM_DEV_ARM_VGIC_GRP_DIST_REGS,
-                   offset, cpu, val, write);
-}
-
-static void kvm_gicc_access(GICState *s, int offset, int cpu,
-                            uint32_t *val, bool write)
-{
-    kvm_gic_access(s, KVM_DEV_ARM_VGIC_GRP_CPU_REGS,
-                   offset, cpu, val, write);
-}
-
 #define for_each_irq_reg(_ctr, _max_irq, _field_width) \
     for (_ctr = 0; _ctr < ((_max_irq) / (32 / (_field_width))); _ctr++)
 
@@ -559,7 +552,7 @@ static void kvm_arm_gic_realize(DeviceState *dev, Error 
**errp)
         return;
     }
 
-    gic_init_irqs_and_mmio(s, kvm_arm_gic_set_irq, NULL);
+    gic_init_irqs_and_mmio(s, kvm_arm_gicv2_set_irq, NULL);
 
     for (i = 0; i < s->num_irq - GIC_INTERNAL; i++) {
         qemu_irq irq = qdev_get_gpio_in(dev, i);
@@ -578,13 +571,14 @@ static void kvm_arm_gic_realize(DeviceState *dev, Error 
**errp)
 
     if (kvm_gic_supports_attr(s, KVM_DEV_ARM_VGIC_GRP_NR_IRQS, 0)) {
         uint32_t numirqs = s->num_irq;
-        kvm_gic_access(s, KVM_DEV_ARM_VGIC_GRP_NR_IRQS, 0, 0, &numirqs, 1);
+        kvm_gic_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_NR_IRQS, 0, 0,
+                       &numirqs, 1);
     }
 
     /* Tell the kernel to complete VGIC initialization now */
     if (kvm_gic_supports_attr(s, KVM_DEV_ARM_VGIC_GRP_CTRL,
                               KVM_DEV_ARM_VGIC_CTRL_INIT)) {
-        kvm_gic_access(s, KVM_DEV_ARM_VGIC_GRP_CTRL,
+        kvm_gic_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_CTRL,
                           KVM_DEV_ARM_VGIC_CTRL_INIT, 0, 0, 1);
     }
 
diff --git a/hw/intc/vgic_common.h b/hw/intc/vgic_common.h
new file mode 100644
index 0000000..130ea64
--- /dev/null
+++ b/hw/intc/vgic_common.h
@@ -0,0 +1,55 @@
+/*
+ * ARM KVM vGIC utility functions
+ *
+ * Copyright (c) 2015 Samsung Electronics
+ * Written by Pavel Fedin
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef QEMU_ARM_VGIC_COMMON_H
+#define QEMU_ARM_VGIC_COMMON_H
+
+/**
+ * kvm_arm_gic_set_irq - Send an IRQ to the in-kernel vGIC
+ * @num_irq: Total number of IRQs configured for the GIC instance
+ * @irq: qemu internal IRQ line number:
+ *  [0..N-1] : external interrupts
+ *  [N..N+31] : PPI (internal) interrupts for CPU 0
+ *  [N+32..N+63] : PPI (internal interrupts for CPU 1
+ * @level: level of the IRQ line.
+ */
+void kvm_arm_gic_set_irq(uint32_t num_irq, int irq, int level);
+
+/**
+ * kvm_gic_access - Read or write vGIC memory-mapped register
+ * @dev_fd: fd of the device to act on
+ * @group: ID of the memory-mapped region
+ * @offset: offset within the region
+ * @cpu: vCPU number
+ * @val: pointer to the storage area for the data
+ * @write - true for writing and false for reading
+ */
+void kvm_gic_access(int dev_fd, int group, int offset, int cpu,
+                    void *val, bool write);
+
+#define kvm_gicd_access(s, offset, cpu, val, write) \
+    kvm_gic_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_DIST_REGS, \
+                   offset, cpu, val, write)
+
+#define kvm_gicc_access(s, offset, cpu, val, write) \
+    kvm_gic_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_CPU_REGS, \
+                   offset, cpu, val, write)
+
+#endif
-- 
1.9.5.msysgit.0