From: Roman Kisel <romank@linux.microsoft.com>
To: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>,
arnd@arndb.de, bhelgaas@google.com, bp@alien8.de,
catalin.marinas@arm.com, dave.hansen@linux.intel.com,
decui@microsoft.com, haiyangz@microsoft.com, hpa@zytor.com,
kw@linux.com, kys@microsoft.com, lenb@kernel.org,
lpieralisi@kernel.org, mingo@redhat.com, mhklinux@outlook.com,
rafael@kernel.org, robh@kernel.org, tglx@linutronix.de,
wei.liu@kernel.org, will@kernel.org, linux-acpi@vger.kernel.org,
linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
linux-hyperv@vger.kernel.org, linux-kernel@vger.kernel.org,
linux-pci@vger.kernel.org, x86@kernel.org
Cc: ssengar@microsoft.com, sunilmut@microsoft.com, vdso@hexbites.dev
Subject: Re: [PATCH v2 1/6] arm64/hyperv: Support DeviceTree
Date: Wed, 15 May 2024 10:33:46 -0700 [thread overview]
Message-ID: <267ef0e2-2384-44bd-81f9-f33dda7bb9d2@linux.microsoft.com> (raw)
In-Reply-To: <1766fc9a-1d10-4c93-a9db-a7e0db8b01e7@linaro.org>
On 5/15/2024 12:45 AM, Krzysztof Kozlowski wrote:
> On 15/05/2024 00:43, Roman Kisel wrote:
>> The Virtual Trust Level platforms rely on DeviceTree, and the
>> arm64/hyperv code supports ACPI only. Update the logic to
>> support DeviceTree on boot as well as ACPI.
>>
>> Signed-off-by: Roman Kisel <romank@linux.microsoft.com>
>> ---
>> arch/arm64/hyperv/mshyperv.c | 34 +++++++++++++++++++++++++++++-----
>> 1 file changed, 29 insertions(+), 5 deletions(-)
>>
>> diff --git a/arch/arm64/hyperv/mshyperv.c b/arch/arm64/hyperv/mshyperv.c
>> index b1a4de4eee29..208a3bcb9686 100644
>> --- a/arch/arm64/hyperv/mshyperv.c
>> +++ b/arch/arm64/hyperv/mshyperv.c
>> @@ -15,6 +15,9 @@
>> #include <linux/errno.h>
>> #include <linux/version.h>
>> #include <linux/cpuhotplug.h>
>> +#include <linux/libfdt.h>
>> +#include <linux/of.h>
>> +#include <linux/of_fdt.h>
>> #include <asm/mshyperv.h>
>>
>> static bool hyperv_initialized;
>> @@ -27,6 +30,29 @@ int hv_get_hypervisor_version(union hv_hypervisor_version_info *info)
>> return 0;
>> }
>>
>> +static bool hyperv_detect_fdt(void)
>> +{
>> +#ifdef CONFIG_OF
>> + const unsigned long hyp_node = of_get_flat_dt_subnode_by_name(
>> + of_get_flat_dt_root(), "hypervisor");
>
> Why do you add an ABI for node name? Although name looks OK, but is it
> really described in the spec that you depend on it? I really do not like
> name dependencies...
Followed the existing DeviceTree's of naming and approaches in the
kernel to surprise less and "invent" even less. As for the spec, the
Hyper-V TLFS'es part discussing Hypervisor Discovery talks about x86
(https://learn.microsoft.com/en-us/virtualization/hyper-v-on-windows/tlfs/feature-discovery)
only and via the ISA-provided means only. For arm64, Hyper-V code
discovers the hypervisor presence via ACPI. Felt only natural to do the
same for DeviceTree and arm64.
>
> Where is the binding for this?
>
Have not added, my mistake. Will place under
Documentation/devicetree/bindings/bus/microsoft,hyperv.yaml
> Best regards,
> Krzysztof
--
Thank you,
Roman
next prev parent reply other threads:[~2024-05-15 17:33 UTC|newest]
Thread overview: 37+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-05-14 22:43 [PATCH v2 0/6] arm64/hyperv: Support Virtual Trust Level Boot Roman Kisel
2024-05-14 22:43 ` [PATCH v2 1/6] arm64/hyperv: Support DeviceTree Roman Kisel
2024-05-15 7:45 ` Krzysztof Kozlowski
2024-05-15 17:33 ` Roman Kisel [this message]
2024-05-20 6:45 ` Krzysztof Kozlowski
2024-05-20 20:36 ` Roman Kisel
2024-05-15 22:02 ` Elliot Berman
2024-05-16 15:27 ` Roman Kisel
2024-06-11 14:55 ` Roman Kisel
2024-05-14 22:43 ` [PATCH v2 2/6] drivers/hv: Enable VTL mode for arm64 Roman Kisel
2024-05-15 13:37 ` Michael Kelley
2024-05-15 18:04 ` Roman Kisel
2024-05-14 22:43 ` [PATCH v2 3/6] drivers/hv: arch-neutral implementation of get_vtl() Roman Kisel
2024-05-15 13:38 ` Michael Kelley
2024-05-15 18:11 ` Roman Kisel
2024-05-14 22:43 ` [PATCH v2 4/6] arm64/hyperv: Boot in a Virtual Trust Level Roman Kisel
2024-05-15 13:39 ` Michael Kelley
2024-05-15 18:13 ` Roman Kisel
2024-05-14 22:43 ` [PATCH v2 5/6] drivers/hv/vmbus: Get the irq number from DeviceTree Roman Kisel
2024-05-15 7:47 ` Krzysztof Kozlowski
2024-05-15 17:05 ` Roman Kisel
2024-05-15 9:42 ` Saurabh Singh Sengar
2024-05-15 16:31 ` Roman Kisel
2024-05-15 13:44 ` Michael Kelley
2024-05-15 18:21 ` Roman Kisel
2024-05-16 2:40 ` kernel test robot
2024-05-17 17:14 ` Rob Herring
2024-05-20 19:25 ` Roman Kisel
2024-05-14 22:43 ` [PATCH v2 6/6] drivers/pci/hyperv/arm64: vPCI MSI IRQ domain from DT Roman Kisel
2024-05-15 9:48 ` Saurabh Singh Sengar
2024-05-15 16:34 ` Roman Kisel
2024-05-15 18:12 ` Bjorn Helgaas
2024-05-15 18:34 ` Roman Kisel
2024-06-07 19:55 ` Bjorn Helgaas
2024-06-11 14:40 ` Roman Kisel
2024-05-15 13:47 ` Michael Kelley
2024-05-15 18:31 ` Roman Kisel
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