Re: [PATCH 04/16] hw/arm: imx: Don't enable PSCI conduit when booting guest in EL3

From: Richard Henderson <richard.henderson@linaro.org>
To: Peter Maydell <peter.maydell@linaro.org>,
	qemu-arm@nongnu.org, qemu-devel@nongnu.org
Cc: "Eduardo Habkost" <eduardo@habkost.net>,
	"Rob Herring" <robh@kernel.org>,
	"Andrew Jeffery" <andrew@aj.id.au>,
	"Andre Przywara" <andre.przywara@arm.com>,
	"Alistair Francis" <alistair@alistair23.me>,
	"Philippe Mathieu-Daudé" <f4bug@amsat.org>,
	"Jean-Christophe Dubois" <jcd@tribudubois.net>,
	"Beniamino Galvani" <b.galvani@gmail.com>,
	"Tyrone Ting" <kfting@nuvoton.com>,
	"Niek Linnenbank" <nieklinnenbank@gmail.com>,
	"Alexander Graf" <agraf@csgraf.de>,
	"Igor Mitsyanko" <i.mitsyanko@gmail.com>,
	"Cédric Le Goater" <clg@kaod.org>,
	"Havard Skinnemoen" <hskinnemoen@google.com>,
	"Edgar E. Iglesias" <edgar.iglesias@gmail.com>,
	"Yanan Wang" <wangyanan55@huawei.com>,
	"Andrey Smirnov" <andrew.smirnov@gmail.com>,
	"Joel Stanley" <joel@jms.id.au>
Subject: Re: [PATCH 04/16] hw/arm: imx: Don't enable PSCI conduit when booting guest in EL3
Date: Mon, 31 Jan 2022 17:43:23 +1100	[thread overview]
Message-ID: <63a2ba3b-18fd-5a55-34f2-f9aa20466edf@linaro.org> (raw)
In-Reply-To: <20220127154639.2090164-5-peter.maydell@linaro.org>

On 1/28/22 02:46, Peter Maydell wrote:
> Change the iMX-SoC based boards to use the new boot.c functionality
> to allow us to enable psci-conduit only if the guest is being booted
> in EL1 or EL2, so that if the user runs guest EL3 firmware code our
> PSCI emulation doesn't get in its way.
> 
> To do this we stop setting the psci-conduit property on the CPU
> objects in the SoC code, and instead set the psci_conduit field in
> the arm_boot_info struct to tell the common boot loader code that
> we'd like PSCI if the guest is starting at an EL that it makes
> sense with.
> 
> This affects the mcimx6ul-evk and mcimx7d-sabre boards.
> 
> Note that for the mcimx7d board, this means that when running guest
> code at EL3 there is currently no way to power on the secondary CPUs,
> because we do not currently have a model of the system reset
> controller module which should be used to do that for the imx7 SoC,
> only for the imx6 SoC.  (Previously EL3 code which knew it was
> running on QEMU could use a PSCI call to do this.) This doesn't
> affect the imx6ul-evk board because it is uniprocessor.
> 
> Signed-off-by: Peter Maydell<peter.maydell@linaro.org>
> ---
> I don't have the i.mx7 manual to hand, so I'm partly making
> assumptions based on the i.mx6 behaviour. If somebody with the
> manual could double-check that it does indeed start up with the
> secondary CPUs powered down via the SRC that would be great.
> ---
>   hw/arm/fsl-imx6ul.c    | 2 --
>   hw/arm/fsl-imx7.c      | 8 ++++----
>   hw/arm/mcimx6ul-evk.c  | 1 +
>   hw/arm/mcimx7d-sabre.c | 1 +
>   4 files changed, 6 insertions(+), 6 deletions(-)

Acked-by: Richard Henderson <richard.henderson@linaro.org>

r~