Hi Detlev,
On Mon, Nov 14, 2022 at 8:48 PM Detlev Casanova
<[email protected]> wrote:
> The 0x3000000 bytes memory region starting at 0x54000000 is
> reserved for the lossy_decompression hardware that will try to
> decompress any data written in the region.
>
> Mark the region as no-map to prevent linux from using it as RAM.
>
> Signed-off-by: Detlev Casanova <[email protected]>
Thanks for your patch!
> --- a/arch/arm64/boot/dts/renesas/r8a77951.dtsi
> +++ b/arch/arm64/boot/dts/renesas/r8a77951.dtsi
> @@ -290,6 +290,18 @@ CPU_SLEEP_1: cpu-sleep-1 {
> };
> };
>
> + reserved-memory {
> + #address-cells = <2>;
> + #size-cells = <2>;
> + ranges;
> +
> + /* device specific region for Lossy Decompression */
> + lossy_decompress: memory-region@54000000 {
> + no-map;
> + reg = <0x00000000 0x54000000 0x0 0x03000000>;
> + };
> + };
This depends on the firmware/boot loader stack. If it configures a
Lossy Decompression region, it should make sure to pass this
info through the various boot loader components to Linux,
just like is already done with the memory regions, RPC-IF state,
and OpTee configuration.
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- [email protected]
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds
On Monday, November 14, 2022 2:57:21 P.M. EST Geert Uytterhoeven wrote:
> Hi Detlev,
>
> On Mon, Nov 14, 2022 at 8:48 PM Detlev Casanova
>
> <[email protected]> wrote:
> > The 0x3000000 bytes memory region starting at 0x54000000 is
> > reserved for the lossy_decompression hardware that will try to
> > decompress any data written in the region.
> >
> > Mark the region as no-map to prevent linux from using it as RAM.
> >
> > Signed-off-by: Detlev Casanova <[email protected]>
>
> Thanks for your patch!
>
> > --- a/arch/arm64/boot/dts/renesas/r8a77951.dtsi
> > +++ b/arch/arm64/boot/dts/renesas/r8a77951.dtsi
> > @@ -290,6 +290,18 @@ CPU_SLEEP_1: cpu-sleep-1 {
> >
> > };
> >
> > };
> >
> > + reserved-memory {
> > + #address-cells = <2>;
> > + #size-cells = <2>;
> > + ranges;
> > +
> > + /* device specific region for Lossy Decompression */
> > + lossy_decompress: memory-region@54000000 {
> > + no-map;
> > + reg = <0x00000000 0x54000000 0x0 0x03000000>;
> > + };
> > + };
>
> This depends on the firmware/boot loader stack. If it configures a
> Lossy Decompression region, it should make sure to pass this
> info through the various boot loader components to Linux,
> just like is already done with the memory regions, RPC-IF state,
> and OpTee configuration.
Thanks for your fast answer ! I didn't realise ATF was doing that, I probably
have a configuration issue in ATF then, I'll rebuild and start from there.
Thanks !
> Gr{oetje,eeting}s,
>
> Geert