From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:38934) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZbPRJ-0003Zm-F7 for qemu-devel@nongnu.org; Mon, 14 Sep 2015 04:48:42 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ZbPRE-0006Fp-E5 for qemu-devel@nongnu.org; Mon, 14 Sep 2015 04:48:41 -0400 Received: from mx1.redhat.com ([209.132.183.28]:36419) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZbPRE-0006Fl-6a for qemu-devel@nongnu.org; Mon, 14 Sep 2015 04:48:36 -0400 Date: Mon, 14 Sep 2015 10:48:30 +0200 From: Igor Mammedov Message-ID: <20150914104830.5a66ac8c@nial.brq.redhat.com> In-Reply-To: <1442100642-7258-4-git-send-email-somlo@cmu.edu> References: <1442100642-7258-1-git-send-email-somlo@cmu.edu> <1442100642-7258-4-git-send-email-somlo@cmu.edu> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [RFC PATCH 3/3] acpi: arm: add fw_cfg device node to dsdt List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: "Gabriel L. Somlo" Cc: peter.maydell@linaro.org, drjones@redhat.com, matt.fleming@intel.com, ehabkost@redhat.com, mst@redhat.com, ard.biesheuvel@linaro.org, qemu-devel@nongnu.org, leif.lindholm@linaro.org, kevin@koconnor.net, kraxel@redhat.com, zhaoshenglong@huawei.com, pbonzini@redhat.com, markmb@redhat.com, lersek@redhat.com, rth@twiddle.net On Sat, 12 Sep 2015 19:30:42 -0400 "Gabriel L. Somlo" wrote: > Add a fw_cfg device node to the ACPI DSDT. This is mostly > informational, as the authoritative fw_cfg MMIO region(s) > are listed in the Device Tree. However, since we are building > ACPI tables, we might as well be thorough while at it... > > Signed-off-by: Gabriel Somlo > --- > > I used surrounding examples to create acpi_dsdt_add_fw_cfg(), and > noticed that none add a _STA method, and many include a 0 _UID even > for nodes with a single instance. I wonder whether 1. I really need > the _UID, and 2. why would we be OK not including a _STA method ? > > Is the #2 answer "because no exisging arm OSPM does in fact check, > and/or care about the absence of _STA" ? :) > > Thanks, > --Gabriel > > hw/arm/virt-acpi-build.c | 18 ++++++++++++++++++ > 1 file changed, 18 insertions(+) > > diff --git a/hw/arm/virt-acpi-build.c b/hw/arm/virt-acpi-build.c > index 9088248..150c9f9 100644 > --- a/hw/arm/virt-acpi-build.c > +++ b/hw/arm/virt-acpi-build.c > @@ -110,6 +110,23 @@ static void acpi_dsdt_add_rtc(Aml *scope, const MemMapEntry *rtc_memmap, > aml_append(scope, dev); > } > > +static void acpi_dsdt_add_fw_cfg(Aml *scope, const MemMapEntry *fw_cfg_memmap) > +{ > + Aml *dev = aml_device("FWCF"); > + aml_append(dev, aml_name_decl("_HID", aml_string("FWCF0001"))); > + > + /* FIXME: is this necessary ? */ in this case you don't need _UID since there is only one instance of given device. > + aml_append(dev, aml_name_decl("_UID", aml_int(0))); > + /* FIXME: why doesn't a _STA get added to any other node ? */ > + aml_append(dev, aml_name_decl("_STA", aml_int(0x0B))); if _STA is not present OSPM must assume that device is present, that's why it's not used for always present devices. 0x0B is used to hide given device (usually driver-less) in Windows's device manager. > + > + Aml *crs = aml_resource_template(); > + aml_append(crs, aml_memory32_fixed(fw_cfg_memmap->base, > + fw_cfg_memmap->size, AML_READ_WRITE)); > + aml_append(dev, aml_name_decl("_CRS", crs)); > + aml_append(scope, dev); > +} > + > static void acpi_dsdt_add_flash(Aml *scope, const MemMapEntry *flash_memmap) > { > Aml *dev, *crs; > @@ -519,6 +536,7 @@ build_dsdt(GArray *table_data, GArray *linker, VirtGuestInfo *guest_info) > (irqmap[VIRT_UART] + ARM_SPI_BASE)); > acpi_dsdt_add_rtc(scope, &memmap[VIRT_RTC], > (irqmap[VIRT_RTC] + ARM_SPI_BASE)); > + acpi_dsdt_add_fw_cfg(scope, &memmap[VIRT_FW_CFG]); > acpi_dsdt_add_flash(scope, &memmap[VIRT_FLASH]); > acpi_dsdt_add_virtio(scope, &memmap[VIRT_MMIO], > (irqmap[VIRT_MMIO] + ARM_SPI_BASE), NUM_VIRTIO_TRANSPORTS);