2023-04-12 17:07:00

by Kathiravan Thirumoorthy

Subject: [PATCH 3/3] arm64: dts: qcom: ipq5332: add few more reserved memory region

In IPQ SoCs, U-boot will collect the system RAM contents upon crash for
the post morterm analysis. If we don't reserve the memory region used by
U-boot, obviously linux will consume it and upon next boot on crash, uboot
will be loaded in the same region, which will lead to loose some of the
data, sometimes we may miss out critical information. So lets reserve the
region used by the U-boot.

Similarly SBL copies some data into the reserved region and it will be
used in the crash scenario. So reserve 1MB for SBL as well.

Signed-off-by: Kathiravan T <[email protected]>
---
arch/arm64/boot/dts/qcom/ipq5332.dtsi | 10 ++++++++++
1 file changed, 10 insertions(+)

diff --git a/arch/arm64/boot/dts/qcom/ipq5332.dtsi b/arch/arm64/boot/dts/qcom/ipq5332.dtsi
index c32217530b41..aec60840a2f0 100644
--- a/arch/arm64/boot/dts/qcom/ipq5332.dtsi
+++ b/arch/arm64/boot/dts/qcom/ipq5332.dtsi
@@ -114,6 +114,16 @@
#size-cells = <2>;
ranges;

+ uboot@4a100000 {
+ reg = <0x0 0x4a100000 0x0 0x400000>;
+ no-map;
+ };
+
+ sbl@4a500000 {
+ reg = <0x0 0x4a500000 0x0 0x100000>;
+ no-map;
+ };
+
tz_mem: tz@4a600000 {
reg = <0x0 0x4a600000 0x0 0x200000>;
no-map;
--
2.17.1

2023-05-16 01:10:17

by Konrad Dybcio

Subject: Re: [PATCH 3/3] arm64: dts: qcom: ipq5332: add few more reserved memory region

On 12.04.2023 18:49, Kathiravan T wrote:
> In IPQ SoCs, U-boot will collect the system RAM contents upon crash for
> the post morterm
s/post morterm/post-mortem ; s/the//

analysis. If we don't reserve the memory region used by
> U-boot, obviously linux will consume it and upon next boot on crash, uboot
> will be loaded in the same region, which will lead to loose
s/loose/loss

some of the
> data, sometimes we may miss out critical information.
So.. is it used to store crash data, or do you load u-boot there?

Or is there some software running at a higher exception level that
collects the dumps and stores it to this region?

Are these regions only used for some sort of crashdump colection?
If so, they could get some more specific names, e.g. uboot-crashdump
or so.

Konrad
So lets reserve the
> region used by the U-boot.
>
> Similarly SBL copies some data into the reserved region and it will be
> used in the crash scenario. So reserve 1MB for SBL as well>
> Signed-off-by: Kathiravan T <[email protected]>
> ---
> arch/arm64/boot/dts/qcom/ipq5332.dtsi | 10 ++++++++++
> 1 file changed, 10 insertions(+)
>
> diff --git a/arch/arm64/boot/dts/qcom/ipq5332.dtsi b/arch/arm64/boot/dts/qcom/ipq5332.dtsi
> index c32217530b41..aec60840a2f0 100644
> --- a/arch/arm64/boot/dts/qcom/ipq5332.dtsi
> +++ b/arch/arm64/boot/dts/qcom/ipq5332.dtsi
> @@ -114,6 +114,16 @@
> #size-cells = <2>;
> ranges;
>
> + uboot@4a100000 {
> + reg = <0x0 0x4a100000 0x0 0x400000>;
> + no-map;
> + };
> +
> + sbl@4a500000 {
> + reg = <0x0 0x4a500000 0x0 0x100000>;
> + no-map;
> + };
> +
> tz_mem: tz@4a600000 {
> reg = <0x0 0x4a600000 0x0 0x200000>;
> no-map;