Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > linux.kernel > #1347721 > unrolled thread

[PATCH v2 0/6] ARM64: meson: GXBaby (S905) and Vega S95 enablement

Back to article view | Back to linux.kernel

Contents

  [PATCH v2 0/6] ARM64: meson: GXBaby (S905) and Vega S95 enablement Andreas Färber <afaerber@suse.de> - 2016-03-02 03:40 +0100
    [PATCH v2 6/6] ARM64: dts: amlogic: Add Tronsmart Vega S95 configs Andreas Färber <afaerber@suse.de> - 2016-03-02 03:40 +0100
    [PATCH v2 5/6] Documentation: devicetree: amlogic: Document Tronsmart Vega S95 boards Andreas Färber <afaerber@suse.de> - 2016-03-02 03:40 +0100
    Re: [PATCH v2 0/6] ARM64: meson: GXBaby (S905) and Vega S95  enablement Mark Rutland <mark.rutland@arm.com> - 2016-03-02 15:00 +0100
      Re: [PATCH v2 0/6] ARM64: meson: GXBaby (S905) and Vega S95  enablement Andreas Färber <afaerber@suse.de> - 2016-03-02 15:40 +0100
        Re: [PATCH v2 0/6] ARM64: meson: GXBaby (S905) and Vega S95  enablement Mark Rutland <mark.rutland@arm.com> - 2016-03-02 16:20 +0100

#1347721 — [PATCH v2 0/6] ARM64: meson: GXBaby (S905) and Vega S95 enablement

Hello,

This series adds initial support for the Amlogic S905 based
Tronsmart Vega S95 Pro, Meta and Telos TV boxes.

v2:
* Pick up previously acked "tronsmart" patch instead (Matthias)
* Drop ARM_GIC selection (Sudeep)
* Change some compatible strings (Sudeep, André)
* Squash some node changes/additions

Note: On the Vega S95 I need to change TEXT_OFFSET as follows,
in order to avoid the vendor U-Boot overwriting itself (fwiu);
for the Mini Mx that's reportedly not necessary.

diff --git a/arch/arm64/Makefile b/arch/arm64/Makefile
index 354d75402ace..b7cebdb8b1ce 100644
--- a/arch/arm64/Makefile
+++ b/arch/arm64/Makefile
@@ -62,7 +62,7 @@ head-y                := arch/arm64/kernel/head.o
 ifeq ($(CONFIG_ARM64_RANDOMIZE_TEXT_OFFSET), y)
 TEXT_OFFSET := $(shell awk 'BEGIN {srand(); printf "0x%03x000\n", int(512 * rand())}')
 else
-TEXT_OFFSET := 0x00080000
+TEXT_OFFSET := 0x01080000
 endif
 
 # KASAN_SHADOW_OFFSET = VA_START + (1 << (VA_BITS - 3)) - (1 << 61)

This in turn runs into an apparent regression introduced with the
text offset randomization:

diff --git a/arch/arm64/kernel/head.S b/arch/arm64/kernel/head.S
index 6ebd204da16a..afdec27c8871 100644
--- a/arch/arm64/kernel/head.S
+++ b/arch/arm64/kernel/head.S
@@ -48,7 +48,7 @@
 #elif (PAGE_OFFSET & 0x1fffff) != 0
 #error PAGE_OFFSET must be at least 2MB aligned
 #elif TEXT_OFFSET > 0x1fffff
-#error TEXT_OFFSET must be less than 2MB
+//#error TEXT_OFFSET must be less than 2MB
 #endif
 
 #define KERNEL_START   _text

https://en.opensuse.org/HCL:VegaS95

https://github.com/afaerber/linux/commits/vegas95-next

Regards,
Andreas

Cc: André Przywara <andre.przywara@arm.com>
Cc: Sudeep Holla <sudeep.holla@arm.com>
Cc: devicetree@vger.kernel.org

Andreas Färber (5):
  ARM64: Enable Amlogic Meson GXBaby platform
  Documentation: devicetree: amlogic: Document Meson GXBaby
  ARM64: dts: Prepare configs for Amlogic Meson GXBaby
  Documentation: devicetree: amlogic: Document Tronsmart Vega S95 boards
  ARM64: dts: amlogic: Add Tronsmart Vega S95 configs

Matthias Brugger (1):
  devicetree: bindings: Add vendor prefix for Tronsmart

 Documentation/devicetree/bindings/arm/amlogic.txt  |   7 +
 .../devicetree/bindings/vendor-prefixes.txt        |   1 +
 arch/arm64/Kconfig.platforms                       |   5 +
 arch/arm64/boot/dts/Makefile                       |   1 +
 arch/arm64/boot/dts/amlogic/Makefile               |   7 +
 .../boot/dts/amlogic/meson-gxbb-vega-s95-meta.dts  |  55 +++++++
 .../boot/dts/amlogic/meson-gxbb-vega-s95-pro.dts   |  55 +++++++
 .../boot/dts/amlogic/meson-gxbb-vega-s95-telos.dts |  55 +++++++
 .../boot/dts/amlogic/meson-gxbb-vega-s95.dtsi      |  55 +++++++
 arch/arm64/boot/dts/amlogic/meson-gxbb.dtsi        | 183 +++++++++++++++++++++
 10 files changed, 424 insertions(+)
 create mode 100644 arch/arm64/boot/dts/amlogic/Makefile
 create mode 100644 arch/arm64/boot/dts/amlogic/meson-gxbb-vega-s95-meta.dts
 create mode 100644 arch/arm64/boot/dts/amlogic/meson-gxbb-vega-s95-pro.dts
 create mode 100644 arch/arm64/boot/dts/amlogic/meson-gxbb-vega-s95-telos.dts
 create mode 100644 arch/arm64/boot/dts/amlogic/meson-gxbb-vega-s95.dtsi
 create mode 100644 arch/arm64/boot/dts/amlogic/meson-gxbb.dtsi

-- 
2.6.2

[toc] | [next] | [standalone]

#1347725 — [PATCH v2 6/6] ARM64: dts: amlogic: Add Tronsmart Vega S95 configs

Add Device Trees for Tronsmart Vega S95 Pro, Meta and Telos TV boxes.

Signed-off-by: Andreas Färber <afaerber@suse.de>
---
 v1 -> v2:
 * Dropped aliases (moved to Meson gxbb .dtsi)
 * Override only status of uart node (moved to Meson gxbb .dtsi)
 
 arch/arm64/boot/dts/amlogic/Makefile               |  4 ++
 .../boot/dts/amlogic/meson-gxbb-vega-s95-meta.dts  | 55 ++++++++++++++++++++++
 .../boot/dts/amlogic/meson-gxbb-vega-s95-pro.dts   | 55 ++++++++++++++++++++++
 .../boot/dts/amlogic/meson-gxbb-vega-s95-telos.dts | 55 ++++++++++++++++++++++
 .../boot/dts/amlogic/meson-gxbb-vega-s95.dtsi      | 55 ++++++++++++++++++++++
 5 files changed, 224 insertions(+)
 create mode 100644 arch/arm64/boot/dts/amlogic/meson-gxbb-vega-s95-meta.dts
 create mode 100644 arch/arm64/boot/dts/amlogic/meson-gxbb-vega-s95-pro.dts
 create mode 100644 arch/arm64/boot/dts/amlogic/meson-gxbb-vega-s95-telos.dts
 create mode 100644 arch/arm64/boot/dts/amlogic/meson-gxbb-vega-s95.dtsi

diff --git a/arch/arm64/boot/dts/amlogic/Makefile b/arch/arm64/boot/dts/amlogic/Makefile
index 1b06c28c67eb..eb672f38f89e 100644
--- a/arch/arm64/boot/dts/amlogic/Makefile
+++ b/arch/arm64/boot/dts/amlogic/Makefile
@@ -1,3 +1,7 @@
+dtb-$(CONFIG_ARCH_MESON) += meson-gxbb-vega-s95-pro.dtb
+dtb-$(CONFIG_ARCH_MESON) += meson-gxbb-vega-s95-meta.dtb
+dtb-$(CONFIG_ARCH_MESON) += meson-gxbb-vega-s95-telos.dtb
+
 always		:= $(dtb-y)
 subdir-y	:= $(dts-dirs)
 clean-files	:= *.dtb
diff --git a/arch/arm64/boot/dts/amlogic/meson-gxbb-vega-s95-meta.dts b/arch/arm64/boot/dts/amlogic/meson-gxbb-vega-s95-meta.dts
new file mode 100644
index 000000000000..399aff9e7975
--- /dev/null
+++ b/arch/arm64/boot/dts/amlogic/meson-gxbb-vega-s95-meta.dts
@@ -0,0 +1,55 @@
+/*
+ * Copyright (c) 2016 Andreas Färber
+ *
+ * This file is dual-licensed: you can use it either under the terms
+ * of the GPL or the X11 license, at your option. Note that this dual
+ * licensing only applies to this file, and not this project as a
+ * whole.
+ *
+ *  a) This library is free software; you can redistribute it and/or
+ *     modify it under the terms of the GNU General Public License as
+ *     published by the Free Software Foundation; either version 2 of the
+ *     License, or (at your option) any later version.
+ *
+ *     This library is distributed in the hope that it will be useful,
+ *     but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *     GNU General Public License for more details.
+ *
+ * Or, alternatively,
+ *
+ *  b) Permission is hereby granted, free of charge, to any person
+ *     obtaining a copy of this software and associated documentation
+ *     files (the "Software"), to deal in the Software without
+ *     restriction, including without limitation the rights to use,
+ *     copy, modify, merge, publish, distribute, sublicense, and/or
+ *     sell copies of the Software, and to permit persons to whom the
+ *     Software is furnished to do so, subject to the following
+ *     conditions:
+ *
+ *     The above copyright notice and this permission notice shall be
+ *     included in all copies or substantial portions of the Software.
+ *
+ *     THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ *     EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
+ *     OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ *     NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
+ *     HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+ *     WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ *     FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ *     OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+/dts-v1/;
+
+#include "meson-gxbb-vega-s95.dtsi"
+
+/ {
+	compatible = "tronsmart,vega-s95-meta", "tronsmart,vega-s95", "amlogic,meson-gxbb";
+	model = "Tronsmart Vega S95 Meta";
+
+	memory {
+		device_type = "memory";
+		reg = <0x0 0x0 0x0 0x80000000>;
+	};
+};
diff --git a/arch/arm64/boot/dts/amlogic/meson-gxbb-vega-s95-pro.dts b/arch/arm64/boot/dts/amlogic/meson-gxbb-vega-s95-pro.dts
new file mode 100644
index 000000000000..ac5a241b5ec2
--- /dev/null
+++ b/arch/arm64/boot/dts/amlogic/meson-gxbb-vega-s95-pro.dts
@@ -0,0 +1,55 @@
+/*
+ * Copyright (c) 2016 Andreas Färber
+ *
+ * This file is dual-licensed: you can use it either under the terms
+ * of the GPL or the X11 license, at your option. Note that this dual
+ * licensing only applies to this file, and not this project as a
+ * whole.
+ *
+ *  a) This library is free software; you can redistribute it and/or
+ *     modify it under the terms of the GNU General Public License as
+ *     published by the Free Software Foundation; either version 2 of the
+ *     License, or (at your option) any later version.
+ *
+ *     This library is distributed in the hope that it will be useful,
+ *     but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *     GNU General Public License for more details.
+ *
+ * Or, alternatively,
+ *
+ *  b) Permission is hereby granted, free of charge, to any person
+ *     obtaining a copy of this software and associated documentation
+ *     files (the "Software"), to deal in the Software without
+ *     restriction, including without limitation the rights to use,
+ *     copy, modify, merge, publish, distribute, sublicense, and/or
+ *     sell copies of the Software, and to permit persons to whom the
+ *     Software is furnished to do so, subject to the following
+ *     conditions:
+ *
+ *     The above copyright notice and this permission notice shall be
+ *     included in all copies or substantial portions of the Software.
+ *
+ *     THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ *     EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
+ *     OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ *     NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
+ *     HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+ *     WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ *     FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ *     OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+/dts-v1/;
+
+#include "meson-gxbb-vega-s95.dtsi"
+
+/ {
+	compatible = "tronsmart,vega-s95-pro", "tronsmart,vega-s95", "amlogic,meson-gxbb";
+	model = "Tronsmart Vega S95 Pro";
+
+	memory {
+		device_type = "memory";
+		reg = <0x0 0x0 0x0 0x40000000>;
+	};
+};
diff --git a/arch/arm64/boot/dts/amlogic/meson-gxbb-vega-s95-telos.dts b/arch/arm64/boot/dts/amlogic/meson-gxbb-vega-s95-telos.dts
new file mode 100644
index 000000000000..fff7bfa2aa39
--- /dev/null
+++ b/arch/arm64/boot/dts/amlogic/meson-gxbb-vega-s95-telos.dts
@@ -0,0 +1,55 @@
+/*
+ * Copyright (c) 2016 Andreas Färber
+ *
+ * This file is dual-licensed: you can use it either under the terms
+ * of the GPL or the X11 license, at your option. Note that this dual
+ * licensing only applies to this file, and not this project as a
+ * whole.
+ *
+ *  a) This library is free software; you can redistribute it and/or
+ *     modify it under the terms of the GNU General Public License as
+ *     published by the Free Software Foundation; either version 2 of the
+ *     License, or (at your option) any later version.
+ *
+ *     This library is distributed in the hope that it will be useful,
+ *     but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *     GNU General Public License for more details.
+ *
+ * Or, alternatively,
+ *
+ *  b) Permission is hereby granted, free of charge, to any person
+ *     obtaining a copy of this software and associated documentation
+ *     files (the "Software"), to deal in the Software without
+ *     restriction, including without limitation the rights to use,
+ *     copy, modify, merge, publish, distribute, sublicense, and/or
+ *     sell copies of the Software, and to permit persons to whom the
+ *     Software is furnished to do so, subject to the following
+ *     conditions:
+ *
+ *     The above copyright notice and this permission notice shall be
+ *     included in all copies or substantial portions of the Software.
+ *
+ *     THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ *     EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
+ *     OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ *     NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
+ *     HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+ *     WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ *     FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ *     OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+/dts-v1/;
+
+#include "meson-gxbb-vega-s95.dtsi"
+
+/ {
+	compatible = "tronsmart,vega-s95-telos", "tronsmart,vega-s95", "amlogic,meson-gxbb";
+	model = "Tronsmart Vega S95 Telos";
+
+	memory {
+		device_type = "memory";
+		reg = <0x0 0x0 0x0 0x80000000>;
+	};
+};
diff --git a/arch/arm64/boot/dts/amlogic/meson-gxbb-vega-s95.dtsi b/arch/arm64/boot/dts/amlogic/meson-gxbb-vega-s95.dtsi
new file mode 100644
index 000000000000..c1fa2667ec5c
--- /dev/null
+++ b/arch/arm64/boot/dts/amlogic/meson-gxbb-vega-s95.dtsi
@@ -0,0 +1,55 @@
+/*
+ * Copyright (c) 2016 Andreas Färber
+ *
+ * This file is dual-licensed: you can use it either under the terms
+ * of the GPL or the X11 license, at your option. Note that this dual
+ * licensing only applies to this file, and not this project as a
+ * whole.
+ *
+ *  a) This library is free software; you can redistribute it and/or
+ *     modify it under the terms of the GNU General Public License as
+ *     published by the Free Software Foundation; either version 2 of the
+ *     License, or (at your option) any later version.
+ *
+ *     This library is distributed in the hope that it will be useful,
+ *     but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *     GNU General Public License for more details.
+ *
+ * Or, alternatively,
+ *
+ *  b) Permission is hereby granted, free of charge, to any person
+ *     obtaining a copy of this software and associated documentation
+ *     files (the "Software"), to deal in the Software without
+ *     restriction, including without limitation the rights to use,
+ *     copy, modify, merge, publish, distribute, sublicense, and/or
+ *     sell copies of the Software, and to permit persons to whom the
+ *     Software is furnished to do so, subject to the following
+ *     conditions:
+ *
+ *     The above copyright notice and this permission notice shall be
+ *     included in all copies or substantial portions of the Software.
+ *
+ *     THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ *     EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
+ *     OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ *     NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
+ *     HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+ *     WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ *     FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ *     OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+#include "meson-gxbb.dtsi"
+
+/ {
+	compatible = "tronsmart,vega-s95", "amlogic,meson-gxbb";
+
+	chosen {
+		stdout-path = "serial0:115200n8";
+	};
+};
+
+&uart_AO {
+	status = "okay";
+};
-- 
2.6.2

[toc] | [prev] | [next] | [standalone]

#1347738 — [PATCH v2 5/6] Documentation: devicetree: amlogic: Document Tronsmart Vega S95 boards

Use "tronsmart,vega-s95" as well as
    "tronsmart,vega-s95-pro",
    "tronsmart,vega-s95-meta" and
    "tronsmart,vega-s95-telos" compatible strings.

Signed-off-by: Andreas Färber <afaerber@suse.de>
---
 v1 -> v2: unchanged
 
 Documentation/devicetree/bindings/arm/amlogic.txt | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/Documentation/devicetree/bindings/arm/amlogic.txt b/Documentation/devicetree/bindings/arm/amlogic.txt
index 776f08ca215f..8a5122ab19b0 100644
--- a/Documentation/devicetree/bindings/arm/amlogic.txt
+++ b/Documentation/devicetree/bindings/arm/amlogic.txt
@@ -22,3 +22,6 @@ Board compatible values:
   - "minix,neo-x8" (Meson8)
   - "tronfy,mxq" (Meson8b)
   - "hardkernel,odroid-c1" (Meson8b)
+  - "tronsmart,vega-s95-pro", "tronsmart,vega-s95" (Meson gxbb)
+  - "tronsmart,vega-s95-meta", "tronsmart,vega-s95" (Meson gxbb)
+  - "tronsmart,vega-s95-telos", "tronsmart,vega-s95" (Meson gxbb)
-- 
2.6.2

[toc] | [prev] | [next] | [standalone]

#1348047 — Re: [PATCH v2 0/6] ARM64: meson: GXBaby (S905) and Vega S95 enablement

On Wed, Mar 02, 2016 at 03:34:55AM +0100, Andreas Färber wrote:
> Hello,
> 
> This series adds initial support for the Amlogic S905 based
> Tronsmart Vega S95 Pro, Meta and Telos TV boxes.
> 
> v2:
> * Pick up previously acked "tronsmart" patch instead (Matthias)
> * Drop ARM_GIC selection (Sudeep)
> * Change some compatible strings (Sudeep, André)
> * Squash some node changes/additions
> 
> Note: On the Vega S95 I need to change TEXT_OFFSET as follows,
> in order to avoid the vendor U-Boot overwriting itself (fwiu);
> for the Mini Mx that's reportedly not necessary.
> 
> diff --git a/arch/arm64/Makefile b/arch/arm64/Makefile
> index 354d75402ace..b7cebdb8b1ce 100644
> --- a/arch/arm64/Makefile
> +++ b/arch/arm64/Makefile
> @@ -62,7 +62,7 @@ head-y                := arch/arm64/kernel/head.o
>  ifeq ($(CONFIG_ARM64_RANDOMIZE_TEXT_OFFSET), y)
>  TEXT_OFFSET := $(shell awk 'BEGIN {srand(); printf "0x%03x000\n", int(512 * rand())}')
>  else
> -TEXT_OFFSET := 0x00080000
> +TEXT_OFFSET := 0x01080000
>  endif
>  
>  # KASAN_SHADOW_OFFSET = VA_START + (1 << (VA_BITS - 3)) - (1 << 61)

Absolute NAK to this. TEXT_OFFSET is not open for platform-specific
modification.

Why can you not just load the Image 2MB higher regardless? Does the
U-Boot on this platform actually read TEXT_OFFSET and take it into
account?

> This in turn runs into an apparent regression introduced with the
> text offset randomization:
> 
> diff --git a/arch/arm64/kernel/head.S b/arch/arm64/kernel/head.S
> index 6ebd204da16a..afdec27c8871 100644
> --- a/arch/arm64/kernel/head.S
> +++ b/arch/arm64/kernel/head.S
> @@ -48,7 +48,7 @@
>  #elif (PAGE_OFFSET & 0x1fffff) != 0
>  #error PAGE_OFFSET must be at least 2MB aligned
>  #elif TEXT_OFFSET > 0x1fffff
> -#error TEXT_OFFSET must be less than 2MB
> +//#error TEXT_OFFSET must be less than 2MB
>  #endif
>  
>  #define KERNEL_START   _text

This is not a regression. As above, TEXT_OFFSET is not supposed to be
modified in a platform-specific manner.

Mark.

[toc] | [prev] | [next] | [standalone]

#1348087 — Re: [PATCH v2 0/6] ARM64: meson: GXBaby (S905) and Vega S95 enablement

Am 02.03.2016 um 14:52 schrieb Mark Rutland:
> On Wed, Mar 02, 2016 at 03:34:55AM +0100, Andreas Färber wrote:
>> Note: On the Vega S95 I need to change TEXT_OFFSET as follows,
>> in order to avoid the vendor U-Boot overwriting itself (fwiu);
>> for the Mini Mx that's reportedly not necessary.
>>
>> diff --git a/arch/arm64/Makefile b/arch/arm64/Makefile
>> index 354d75402ace..b7cebdb8b1ce 100644
>> --- a/arch/arm64/Makefile
>> +++ b/arch/arm64/Makefile
>> @@ -62,7 +62,7 @@ head-y                := arch/arm64/kernel/head.o
>>  ifeq ($(CONFIG_ARM64_RANDOMIZE_TEXT_OFFSET), y)
>>  TEXT_OFFSET := $(shell awk 'BEGIN {srand(); printf "0x%03x000\n", int(512 * rand())}')
>>  else
>> -TEXT_OFFSET := 0x00080000
>> +TEXT_OFFSET := 0x01080000
>>  endif
>>  
>>  # KASAN_SHADOW_OFFSET = VA_START + (1 << (VA_BITS - 3)) - (1 << 61)
> 
> Absolute NAK to this. TEXT_OFFSET is not open for platform-specific
> modification.

Please read again. There is nothing to NAK here, it's a workaround for
testing my patches on my device! Even my own git queue has it clearly
labeled as "HACK:".

Nothing you say here indicates that this is breaking any particular
kernel feature or damaging the device, so unless you propose a different
way to solve the problem I see no way around it for now.

> Why can you not just load the Image 2MB higher regardless? Does the
> U-Boot on this platform actually read TEXT_OFFSET and take it into
> account?

Yes, U-Boot checks the ELF(?) header and tries to copy the image to the
indicated offset if it isn't loaded there already. The vendor's kernel
has the adjusted offset and works; if I use unmodified mainline kernels
then I get weird exceptions from before entering the kernel, my
assumption being that U-Boot code gets overwritten.

http://openlinux.amlogic.com:8000/download/ARM/u-boot/

This problem might go away if we had a proper upstream-based U-Boot; I'm
not familiar enough with U-Boot to fix that myself and would hate to
mess with U-Boot on eMMC, for lack of JTAG pins on this device.

The Odroid-C2 (which I do not have access to yet) has instructions how
to place U-Boot on an SD card, making it safer to experiment with.
http://odroid.com/dokuwiki/doku.php?id=en:c2_partition_table

>> This in turn runs into an apparent regression introduced with the
>> text offset randomization:
>>
>> diff --git a/arch/arm64/kernel/head.S b/arch/arm64/kernel/head.S
>> index 6ebd204da16a..afdec27c8871 100644
>> --- a/arch/arm64/kernel/head.S
>> +++ b/arch/arm64/kernel/head.S
>> @@ -48,7 +48,7 @@
>>  #elif (PAGE_OFFSET & 0x1fffff) != 0
>>  #error PAGE_OFFSET must be at least 2MB aligned
>>  #elif TEXT_OFFSET > 0x1fffff
>> -#error TEXT_OFFSET must be less than 2MB
>> +//#error TEXT_OFFSET must be less than 2MB
>>  #endif
>>  
>>  #define KERNEL_START   _text
> 
> This is not a regression. As above, TEXT_OFFSET is not supposed to be
> modified in a platform-specific manner.

It is in fact an unexplained behavioral change in
http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=da57a369d3bc5cd61db90f7e9555840381db9b09

diff --git a/arch/arm64/kernel/head.S b/arch/arm64/kernel/head.S
index 3ba0fc0..69dafe9 100644
--- a/arch/arm64/kernel/head.S
+++ b/arch/arm64/kernel/head.S
@@ -37,8 +37,12 @@

 #define KERNEL_RAM_VADDR	(PAGE_OFFSET + TEXT_OFFSET)

-#if (KERNEL_RAM_VADDR & 0xfffff) != 0x80000
-#error KERNEL_RAM_VADDR must start at 0xXXX80000
+#if (TEXT_OFFSET & 0xf) != 0
+#error TEXT_OFFSET must be at least 16B aligned
+#elif (PAGE_OFFSET & 0xfffff) != 0
+#error PAGE_OFFSET must be at least 2MB aligned
+#elif TEXT_OFFSET > 0xfffff
+#error TEXT_OFFSET must be less than 2MB
 #endif

 	.macro	pgtbl, ttb0, ttb1, virt_to_phys

As you can see, previously 0x1080000 was a valid value, and this
regressed with the new randomization feature. It obviously works with
the larger offset for me, so the "must be" seems questionable.

Regards,
Andreas

-- 
SUSE Linux GmbH, Maxfeldstr. 5, 90409 Nürnberg, Germany
GF: Felix Imendörffer, Jane Smithard, Graham Norton; HRB 21284 (AG Nürnberg)

[toc] | [prev] | [next] | [standalone]

#1348141 — Re: [PATCH v2 0/6] ARM64: meson: GXBaby (S905) and Vega S95 enablement

On Wed, Mar 02, 2016 at 03:31:52PM +0100, Andreas Färber wrote:
> Am 02.03.2016 um 14:52 schrieb Mark Rutland:
> > On Wed, Mar 02, 2016 at 03:34:55AM +0100, Andreas Färber wrote:
> >> Note: On the Vega S95 I need to change TEXT_OFFSET as follows,
> >> in order to avoid the vendor U-Boot overwriting itself (fwiu);
> >> for the Mini Mx that's reportedly not necessary.
> >>
> >> diff --git a/arch/arm64/Makefile b/arch/arm64/Makefile
> >> index 354d75402ace..b7cebdb8b1ce 100644
> >> --- a/arch/arm64/Makefile
> >> +++ b/arch/arm64/Makefile
> >> @@ -62,7 +62,7 @@ head-y                := arch/arm64/kernel/head.o
> >>  ifeq ($(CONFIG_ARM64_RANDOMIZE_TEXT_OFFSET), y)
> >>  TEXT_OFFSET := $(shell awk 'BEGIN {srand(); printf "0x%03x000\n", int(512 * rand())}')
> >>  else
> >> -TEXT_OFFSET := 0x00080000
> >> +TEXT_OFFSET := 0x01080000
> >>  endif
> >>  
> >>  # KASAN_SHADOW_OFFSET = VA_START + (1 << (VA_BITS - 3)) - (1 << 61)
> > 
> > Absolute NAK to this. TEXT_OFFSET is not open for platform-specific
> > modification.
> 
> Please read again. There is nothing to NAK here, it's a workaround for
> testing my patches on my device! Even my own git queue has it clearly
> labeled as "HACK:".

Sure; I appreciate you need a workaround for the broken bootloader
currently on the device.

I'm simply heading off any attempts to upstream such changes.

> Nothing you say here indicates that this is breaking any particular
> kernel feature or damaging the device, so unless you propose a different
> way to solve the problem I see no way around it for now.

As far as I am aware, this should not result in damage to your device.

However, it runs directly counter to single-image, and other parts of
the kernel _may_ rely on the existing limits on TEXT_OFFSET. So it's not
suitable for upstream, and you _may_ encounter issues as a result.

> > Why can you not just load the Image 2MB higher regardless? Does the
> > U-Boot on this platform actually read TEXT_OFFSET and take it into
> > account?
> 
> Yes, U-Boot checks the ELF(?) header and tries to copy the image to the
> indicated offset if it isn't loaded there already. The vendor's kernel
> has the adjusted offset and works;

So the vendor deliberately changed the kernel Image in an unsupported
fashion, resulting in a divergent boot protocol.

This is incredibly unfortunate.

> if I use unmodified mainline kernels then I get weird exceptions from
> before entering the kernel, my assumption being that U-Boot code gets
> overwritten.
> 
> http://openlinux.amlogic.com:8000/download/ARM/u-boot/
> 
> This problem might go away if we had a proper upstream-based U-Boot; I'm
> not familiar enough with U-Boot to fix that myself and would hate to
> mess with U-Boot on eMMC, for lack of JTAG pins on this device.
 
> The Odroid-C2 (which I do not have access to yet) has instructions how
> to place U-Boot on an SD card, making it safer to experiment with.
> http://odroid.com/dokuwiki/doku.php?id=en:c2_partition_table

This is probably the right path to a solution.

> >> This in turn runs into an apparent regression introduced with the
> >> text offset randomization:
> >>
> >> diff --git a/arch/arm64/kernel/head.S b/arch/arm64/kernel/head.S
> >> index 6ebd204da16a..afdec27c8871 100644
> >> --- a/arch/arm64/kernel/head.S
> >> +++ b/arch/arm64/kernel/head.S
> >> @@ -48,7 +48,7 @@
> >>  #elif (PAGE_OFFSET & 0x1fffff) != 0
> >>  #error PAGE_OFFSET must be at least 2MB aligned
> >>  #elif TEXT_OFFSET > 0x1fffff
> >> -#error TEXT_OFFSET must be less than 2MB
> >> +//#error TEXT_OFFSET must be less than 2MB
> >>  #endif
> >>  
> >>  #define KERNEL_START   _text
> > 
> > This is not a regression. As above, TEXT_OFFSET is not supposed to be
> > modified in a platform-specific manner.
> 
> It is in fact an unexplained behavioral change in
> http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=da57a369d3bc5cd61db90f7e9555840381db9b09

Yes, strictly speaking it is a change.

No, it is not a regression, since TEXT_OFFSET was _never_ open to such
platform-specific modification.

Thanks,
Mark.

[toc] | [prev] | [standalone]

Back to top | Article view | linux.kernel

csiph-web