Re: [Qemu-devel] [Qemu-arm] [PATCH 05/19] armv7m: Forward idau property to CPU object

[Peter Maydell <peter.maydell@linaro.org>]

On 20 February 2018 at 18:03, Peter Maydell <peter.maydell@linaro.org> wrote:
> Create an "idau" property on the armv7m container object which
> we can forward to the CPU object. Annoyingly, we can't use
> object_property_add_alias() because the CPU object we want to
> forward to doesn't exist until the armv7m container is realized.
>
> Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
> ---
>  include/hw/arm/armv7m.h | 3 +++
>  hw/arm/armv7m.c         | 7 +++++++
>  2 files changed, 10 insertions(+)
>
> diff --git a/include/hw/arm/armv7m.h b/include/hw/arm/armv7m.h
> index 35ab757264..5c3f406ccc 100644
> --- a/include/hw/arm/armv7m.h
> +++ b/include/hw/arm/armv7m.h
> @@ -12,6 +12,7 @@
>
>  #include "hw/sysbus.h"
>  #include "hw/intc/armv7m_nvic.h"
> +#include "target/arm/idau.h"
>
>  #define TYPE_BITBAND "ARM,bitband-memory"
>  #define BITBAND(obj) OBJECT_CHECK(BitBandState, (obj), TYPE_BITBAND)
> @@ -40,6 +41,7 @@ typedef struct {
>   * + Property "memory": MemoryRegion defining the physical address space
>   *   that CPU accesses see. (The NVIC, bitbanding and other CPU-internal
>   *   devices will be automatically layered on top of this view.)
> + * + Property "idau": IDAU interface (forwarded to CPU object)
>   */
>  typedef struct ARMv7MState {
>      /*< private >*/
> @@ -58,6 +60,7 @@ typedef struct ARMv7MState {
>      char *cpu_type;
>      /* MemoryRegion the board provides to us (with its devices, RAM, etc) */
>      MemoryRegion *board_memory;
> +    Object *idau;
>  } ARMv7MState;
>
>  #endif
> diff --git a/hw/arm/armv7m.c b/hw/arm/armv7m.c
> index facc536b07..189066812c 100644
> --- a/hw/arm/armv7m.c
> +++ b/hw/arm/armv7m.c
> @@ -19,6 +19,7 @@
>  #include "sysemu/qtest.h"
>  #include "qemu/error-report.h"
>  #include "exec/address-spaces.h"
> +#include "target/arm/idau.h"
>
>  /* Bitbanded IO.  Each word corresponds to a single bit.  */
>
> @@ -162,6 +163,11 @@ static void armv7m_realize(DeviceState *dev, Error **errp)
>
>      object_property_set_link(OBJECT(s->cpu), OBJECT(&s->container), "memory",
>                               &error_abort);
> +    object_property_set_link(OBJECT(s->cpu), s->idau, "idau", &err);
> +    if (err != NULL) {
> +        error_propagate(errp, err);
> +        return;
> +    }

This turns out to not quite be right -- if the CPU doesn't have
the "idau" property (ie it is a v7M CPU like the cortex-m3) then
the object_property_set_link will fail. This causes 'make check'
to fail when it tries to run the M3/M4 boards with
"qemu-system-aarch64: Property '.init-svtor' not found"

The fix is to squash in this:

diff --git a/hw/arm/armv7m.c b/hw/arm/armv7m.c
index 149aa07cd5..70871eb139 100644
--- a/hw/arm/armv7m.c
+++ b/hw/arm/armv7m.c
@@ -163,10 +163,12 @@ static void armv7m_realize(DeviceState *dev, Error **errp)

     object_property_set_link(OBJECT(s->cpu), OBJECT(&s->container), "memory",
                              &error_abort);
-    object_property_set_link(OBJECT(s->cpu), s->idau, "idau", &err);
-    if (err != NULL) {
-        error_propagate(errp, err);
-        return;
+    if (object_property_find(OBJECT(s->cpu), "idau", NULL)) {
+        object_property_set_link(OBJECT(s->cpu), s->idau, "idau", &err);
+        if (err != NULL) {
+            error_propagate(errp, err);
+            return;
+        }
     }
     object_property_set_uint(OBJECT(s->cpu), s->init_svtor,
"init-svtor", &err);
     if (err != NULL) {

which I propose to do in putting the patchset into target-arm.next.

Similarly for init-svtor in the patch later in this series which adds that.

thanks
-- PMM