From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:38672) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZHpdW-0000A5-Qr for qemu-devel@nongnu.org; Wed, 22 Jul 2015 04:44:23 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ZHpdT-0002KX-KQ for qemu-devel@nongnu.org; Wed, 22 Jul 2015 04:44:22 -0400 Received: from mx1.redhat.com ([209.132.183.28]:53858) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZHpdT-0002KI-C8 for qemu-devel@nongnu.org; Wed, 22 Jul 2015 04:44:19 -0400 Date: Wed, 22 Jul 2015 10:44:13 +0200 From: Marc =?UTF-8?B?TWFyw60=?= Message-ID: <20150722104413.2900bca1@markmb_rh> In-Reply-To: References: <1437494626-3773-1-git-send-email-markmb@redhat.com> <1437494626-3773-5-git-send-email-markmb@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Subject: Re: [Qemu-devel] [RFC 4/7] enable fw_cfg dma for arm virt List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Peter Maydell Cc: Stefan Hajnoczi , Paolo Bonzini , Kevin O'Connor , QEMU Developers , Gerd Hoffmann On Tue, 21 Jul 2015 18:04:31 +0100 Peter Maydell wrote: > On 21 July 2015 at 17:03, Marc Mar=C3=AD wrote: > > From: Gerd Hoffmann > > > > Signed-off-by: Gerd Hoffmann > > --- > > docs/specs/fw_cfg.txt | 6 ++++++ > > hw/arm/virt.c | 11 ++++++++--- > > 2 files changed, 14 insertions(+), 3 deletions(-) > > > > diff --git a/docs/specs/fw_cfg.txt b/docs/specs/fw_cfg.txt > > index 64d9192..eac83a1 100644 > > --- a/docs/specs/fw_cfg.txt > > +++ b/docs/specs/fw_cfg.txt > > @@ -167,6 +167,12 @@ If a partial transfer happened before an error > > occured the address and length registers indicate how much data has > > been transfered successfully. > > > > +=3D=3D Register Locations =3D=3D > > + > > +=3D=3D=3D arm =3D=3D=3D > > + > > +classic fw_cfg base + 16 > > + > > =3D Host-side API =3D > > > > The following functions are available to the QEMU programmer for > > adding diff --git a/hw/arm/virt.c b/hw/arm/virt.c > > index 374660c..d05f6a4 100644 > > --- a/hw/arm/virt.c > > +++ b/hw/arm/virt.c > > @@ -606,13 +606,13 @@ static void create_flash(const VirtBoardInfo > > *vbi) g_free(nodename); > > } > > > > -static void create_fw_cfg(const VirtBoardInfo *vbi) > > +static void create_fw_cfg(AddressSpace *as, const VirtBoardInfo > > *vbi) { > > hwaddr base =3D vbi->memmap[VIRT_FW_CFG].base; > > hwaddr size =3D vbi->memmap[VIRT_FW_CFG].size; > > char *nodename; > > > > - fw_cfg_init_mem_wide(base + 8, base, 8, 0, NULL); > > + fw_cfg_init_mem_wide(base + 8, base, 8, 16, as); > > > > nodename =3D g_strdup_printf("/fw-cfg@%" PRIx64, base); > > qemu_fdt_add_subnode(vbi->fdt, nodename); >=20 > Don't we need to also update the device tree (and the spec for > that!) to indicate that we're providing a with-DMA fw-cfg > device ? >=20 > > @@ -800,6 +800,7 @@ static void machvirt_init(MachineState *machine) > > VirtGuestInfoState *guest_info_state =3D g_malloc0(sizeof > > *guest_info_state); VirtGuestInfo *guest_info =3D > > &guest_info_state->info; char **cpustr; > > + AddressSpace *as =3D NULL; > > > > if (!cpu_model) { > > cpu_model =3D "cortex-a15"; > > @@ -837,6 +838,10 @@ static void machvirt_init(MachineState > > *machine) } > > cpuobj =3D object_new(object_class_get_name(oc)); > > > > + if (!as) { > > + as =3D CPU(cpuobj)->as; > > + } >=20 > Is this really the right AddressSpace to use? Fishing > around in the CPU object seems a bit dubious... >=20 I have not touched this part, I touched the x86 part, but the same comment applies in both places: I don't know much about how and why address spaces are used in QEMU, so I'm not really sure which address space should I use for this purpose. I'd appreciate some help in the issue. Thanks Marc