From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:37830) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZbAl7-0001YB-J0 for qemu-devel@nongnu.org; Sun, 13 Sep 2015 13:08:10 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ZbAl3-0000IQ-Hk for qemu-devel@nongnu.org; Sun, 13 Sep 2015 13:08:09 -0400 Received: from smtp.andrew.cmu.edu ([128.2.105.202]:42761) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZbAl3-0000IG-Dg for qemu-devel@nongnu.org; Sun, 13 Sep 2015 13:08:05 -0400 Date: Sun, 13 Sep 2015 13:07:48 -0400 From: "Gabriel L. Somlo" Message-ID: <20150913170748.GA26131@GLSMBP.INI.CMU.EDU> References: <1442100642-7258-1-git-send-email-somlo@cmu.edu> <1442100642-7258-3-git-send-email-somlo@cmu.edu> <20150913144328-mutt-send-email-mst@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20150913144328-mutt-send-email-mst@redhat.com> Subject: Re: [Qemu-devel] [RFC PATCH 2/3] acpi: pc: add fw_cfg device node to ssdt List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: "Michael S. Tsirkin" Cc: peter.maydell@linaro.org, drjones@redhat.com, matt.fleming@intel.com, ehabkost@redhat.com, ard.biesheuvel@linaro.org, zhaoshenglong@huawei.com, qemu-devel@nongnu.org, leif.lindholm@linaro.org, kevin@koconnor.net, kraxel@redhat.com, pbonzini@redhat.com, imammedo@redhat.com, markmb@redhat.com, lersek@redhat.com, rth@twiddle.net On Sun, Sep 13, 2015 at 02:45:23PM +0300, Michael S. Tsirkin wrote: > On Sat, Sep 12, 2015 at 07:30:41PM -0400, Gabriel L. Somlo wrote: > > Add a fw_cfg device node to the ACPI SSDT. While the guest-side > > BIOS can't utilize this information (since it has to access the > > hard-coded fw_cfg device to extract ACPI tables to begin with), > > having fw_cfg listed in ACPI will help the guest kernel keep a > > more accurate inventory of in-use IO port regions. > > > > Signed-off-by: Gabriel Somlo > > --- > > hw/i386/acpi-build.c | 19 +++++++++++++++++++ > > 1 file changed, 19 insertions(+) > > > > diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c > > index 95e0c65..9d0ec22 100644 > > --- a/hw/i386/acpi-build.c > > +++ b/hw/i386/acpi-build.c > > @@ -1071,6 +1071,25 @@ build_ssdt(GArray *table_data, GArray *linker, > > aml_append(scope, aml_name_decl("_S5", pkg)); > > aml_append(ssdt, scope); > > > > + if (guest_info->fw_cfg) { > > + scope = aml_scope("\\_SB"); > > + dev = aml_device("FWCF"); > > + > > + aml_append(dev, aml_name_decl("_HID", aml_string("FWCF0001"))); > > Generally that's an illegal HID. If this device has a driver, > use QEMU as a prefix. Otherwise, use one of the pre-defined ones > with a PNP ISA ID. I'm working on a sysfs driver to allow access to fw_cfg files via the guest kernel (similar to e.g. /sys/firmware/dmi/entries/...). That probably means I should go with QEMU0002 (0001 is already assigned to the pvpanic device). I'll use that in v2, which I'll send out once I get some feedback from the arm side as well. Thanks much, --Gabriel > > + /* device present, functioning, decoding, not shown in UI */ > > + aml_append(dev, aml_name_decl("_STA", aml_int(0xB))); > > + > > + crs = aml_resource_template(); > > + aml_append(crs, > > + aml_io(AML_DECODE16, FW_CFG_IO_BASE, FW_CFG_IO_BASE, > > + 0x01, FW_CFG_IO_SIZE) > > + ); > > + aml_append(dev, aml_name_decl("_CRS", crs)); > > + > > + aml_append(scope, dev); > > + aml_append(ssdt, scope); > > + } > > + > > if (misc->applesmc_io_base) { > > scope = aml_scope("\\_SB.PCI0.ISA"); > > dev = aml_device("SMC"); > > -- > > 2.4.3