Re: [PULL v2 1/1] loongarch: Change the UEFI loading mode to loongarch

From: chen huacai <zltjiangshi@gmail.com>
To: lixianglai <lixianglai@loongson.cn>
Cc: "Philippe Mathieu-Daudé" <philmd@linaro.org>,
	"Song Gao" <gaosong@loongson.cn>,
	qemu-devel@nongnu.org, peter.maydell@linaro.org,
	"Andrea Bolognani" <abologna@redhat.com>,
	maobibo@loongson.cn, zhaotianrui@loongson.cn
Subject: Re: [PULL v2 1/1] loongarch: Change the UEFI loading mode to loongarch
Date: Wed, 6 Mar 2024 22:56:10 +0800	[thread overview]
Message-ID: <CABDp7VqyOL9OdxRohru74CyhQzR7W6MwKcg8WCvOVWJz1echMA@mail.gmail.com> (raw)
In-Reply-To: <5e2419ec-6c1f-e21c-2105-fadb5971239c@loongson.cn>

Hi, Xianglai,

How to pass the BIOS file to qemu after this patch? With the old
cmdline I get an RCU stall and freeze the kvm host.

Huacai

On Sat, Mar 2, 2024 at 12:14 PM lixianglai <lixianglai@loongson.cn> wrote:
>
> Hi Philippe:
>
> On 29/2/24 12:38, Song Gao wrote:
>
> From: Xianglai Li <lixianglai@loongson.cn>
>
> The UEFI loading mode in loongarch is very different
> from that in other architectures:loongarch's UEFI code
> is in rom, while other architectures' UEFI code is in flash.
>
> loongarch UEFI can be loaded as follows:
> -machine virt,pflash=pflash0-format
> -bios ./QEMU_EFI.fd
>
> Other architectures load UEFI using the following methods:
> -machine virt,pflash0=pflash0-format,pflash1=pflash1-format
>
> loongarch's UEFI loading method makes qemu and libvirt incompatible
> when using NVRAM, and the cost of loongarch's current loading method
> far outweighs the benefits, so we decided to use the same UEFI loading
> scheme as other architectures.
>
>
> FYI I'm still trying to find a way to avoid that, planning to discuss
> more with libvirt folks. Well, maybe it is a waste of my time and I
> should just stop worrying / caring about this long standing issue.
>
> Thank you so much for your attention to this issue
>
> and your long-standing contributions to the community!!:-)
>
> Best regards,
>
> Xianglai.
>
>
> Cc: Andrea Bolognani <abologna@redhat.com>
> Cc: maobibo@loongson.cn
> Cc: Philippe Mathieu-Daudé <philmd@linaro.org>
> Cc: Song Gao <gaosong@loongson.cn>
> Cc: zhaotianrui@loongson.cn
> Signed-off-by: Xianglai Li <lixianglai@loongson.cn>
> Tested-by: Andrea Bolognani <abologna@redhat.com>
> Reviewed-by: Song Gao <gaosong@loongson.cn>
> Message-Id: <0bd892aa9b88e0f4cc904cb70efd0251fc1cde29.1708336919.git.lixianglai@loongson.cn>
> Signed-off-by: Song Gao <gaosong@loongson.cn>
> ---
>   hw/loongarch/acpi-build.c   |  29 +++++++++--
>   hw/loongarch/virt.c         | 101 ++++++++++++++++++++++++++----------
>   include/hw/loongarch/virt.h |  10 ++--
>   3 files changed, 107 insertions(+), 33 deletions(-)
>
>

-- 
Huacai Chen