[Qemu-devel] [PATCH] arm/virt: Use PSCI v0.2 function IDs in the DT when KVM uses PSCI v0.2

[Christoffer Dall]

The current code supplies the PSCI v0.1 funciton IDs in the DT even when
KVM uses PSCI v0.2.

This will break guest kernels that only support PSCI v0.1 as they will
use the IDs provided in the DT.  Guest kernels with PSCI v0.2 support
are not affected by this patch, because they ignore the function IDs in
the device tree and rely on the architecture definition.

Define QEMU versions of the constants and check that they correspond to
the Linux defines on Linux build hosts.  After this patch, both guest
kernels with PSCI v0.1 support and guest kernels with PSCI v0.2 should
work.

Tested on TC2 for 32-bit and APM Mustang for 64-bit (aarch64 guest
only).  Both cases tested with 3.14 and linus/master and verified I
could bring up 2 cpus with both guest kernels.

Signed-off-by: Christoffer Dall <address@hidden>
---
 hw/arm/virt.c           | 25 ++++++++++++++++++++++---
 target-arm/kvm-consts.h | 23 +++++++++++++++++++++++
 2 files changed, 45 insertions(+), 3 deletions(-)

diff --git a/hw/arm/virt.c b/hw/arm/virt.c
index ba94298..4e882bc 100644
--- a/hw/arm/virt.c
+++ b/hw/arm/virt.c
@@ -194,20 +194,39 @@ static void fdt_add_psci_node(const VirtBoardInfo *vbi)
 
     /* No PSCI for TCG yet */
     if (kvm_enabled()) {
+        uint32_t cpu_off_fn;
+        uint32_t cpu_on_fn;
+        uint32_t migrate_fn;
+
         qemu_fdt_add_subnode(fdt, "/psci");
         if (armcpu->psci_version == 2) {
             const char comp[] = "arm,psci-0.2\0arm,psci";
             qemu_fdt_setprop(fdt, "/psci", "compatible", comp, sizeof(comp));
+
+            if (arm_feature(&armcpu->env, ARM_FEATURE_AARCH64)) {
+                cpu_off_fn = QEMU_PSCI_0_2_FN_CPU_OFF;
+                cpu_on_fn = QEMU_PSCI_0_2_FN64_CPU_ON;
+                migrate_fn = QEMU_PSCI_0_2_FN64_MIGRATE;
+            } else {
+                cpu_off_fn = QEMU_PSCI_0_2_FN_CPU_OFF;
+                cpu_on_fn = QEMU_PSCI_0_2_FN_CPU_ON;
+                migrate_fn = QEMU_PSCI_0_2_FN_MIGRATE;
+            }
         } else {
             qemu_fdt_setprop_string(fdt, "/psci", "compatible", "arm,psci");
+
+            cpu_off_fn = PSCI_FN_CPU_OFF;
+            cpu_on_fn = PSCI_FN_CPU_ON;
+            migrate_fn = PSCI_FN_MIGRATE;
         }
 
         qemu_fdt_setprop_string(fdt, "/psci", "method", "hvc");
         qemu_fdt_setprop_cell(fdt, "/psci", "cpu_suspend",
                                   PSCI_FN_CPU_SUSPEND);
-        qemu_fdt_setprop_cell(fdt, "/psci", "cpu_off", PSCI_FN_CPU_OFF);
-        qemu_fdt_setprop_cell(fdt, "/psci", "cpu_on", PSCI_FN_CPU_ON);
-        qemu_fdt_setprop_cell(fdt, "/psci", "migrate", PSCI_FN_MIGRATE);
+
+        qemu_fdt_setprop_cell(fdt, "/psci", "cpu_off", cpu_off_fn);
+        qemu_fdt_setprop_cell(fdt, "/psci", "cpu_on", cpu_on_fn);
+        qemu_fdt_setprop_cell(fdt, "/psci", "migrate", migrate_fn);
     }
 }
 
diff --git a/target-arm/kvm-consts.h b/target-arm/kvm-consts.h
index 6009a33..a8df135 100644
--- a/target-arm/kvm-consts.h
+++ b/target-arm/kvm-consts.h
@@ -17,6 +17,7 @@
 #ifdef CONFIG_KVM
 #include "qemu/compiler.h"
 #include <linux/kvm.h>
+#include <linux/psci.h>
 
 #define MISMATCH_CHECK(X, Y) QEMU_BUILD_BUG_ON(X != Y)
 
@@ -50,6 +51,28 @@ MISMATCH_CHECK(PSCI_FN_CPU_OFF, KVM_PSCI_FN_CPU_OFF)
 MISMATCH_CHECK(PSCI_FN_CPU_ON, KVM_PSCI_FN_CPU_ON)
 MISMATCH_CHECK(PSCI_FN_MIGRATE, KVM_PSCI_FN_MIGRATE)
 
+#define QEMU_PSCI_0_2_FN_BASE 0x84000000
+#define QEMU_PSCI_0_2_FN(n) (QEMU_PSCI_0_2_FN_BASE + (n))
+
+#define QEMU_PSCI_0_2_64BIT 0x40000000
+#define QEMU_PSCI_0_2_FN64_BASE \
+        (QEMU_PSCI_0_2_FN_BASE + QEMU_PSCI_0_2_64BIT)
+#define QEMU_PSCI_0_2_FN64(n) (QEMU_PSCI_0_2_FN64_BASE + (n))
+
+#define QEMU_PSCI_0_2_FN_CPU_OFF QEMU_PSCI_0_2_FN(2)
+#define QEMU_PSCI_0_2_FN_CPU_ON QEMU_PSCI_0_2_FN(3)
+#define QEMU_PSCI_0_2_FN_MIGRATE QEMU_PSCI_0_2_FN(5)
+
+#define QEMU_PSCI_0_2_FN64_CPU_OFF QEMU_PSCI_0_2_FN64(2)
+#define QEMU_PSCI_0_2_FN64_CPU_ON QEMU_PSCI_0_2_FN64(3)
+#define QEMU_PSCI_0_2_FN64_MIGRATE QEMU_PSCI_0_2_FN64(5)
+
+MISMATCH_CHECK(QEMU_PSCI_0_2_FN_CPU_OFF, PSCI_0_2_FN_CPU_OFF)
+MISMATCH_CHECK(QEMU_PSCI_0_2_FN_CPU_ON, PSCI_0_2_FN_CPU_ON)
+MISMATCH_CHECK(QEMU_PSCI_0_2_FN_MIGRATE, PSCI_0_2_FN_MIGRATE)
+MISMATCH_CHECK(QEMU_PSCI_0_2_FN64_CPU_ON, PSCI_0_2_FN64_CPU_ON)
+MISMATCH_CHECK(QEMU_PSCI_0_2_FN64_MIGRATE, PSCI_0_2_FN64_MIGRATE)
+
 /* Note that KVM uses overlapping values for AArch32 and AArch64
  * target CPU numbers. AArch32 targets:
  */
-- 
2.0.0