Add support for Airoha EN7523 SoC

---
 Documentation/devicetree/bindings/vendor-prefixes.yaml | 2 ++
 1 file changed, 2 insertions(+)

Documentation/devicetree/bindings/vendor-prefixes.yaml +2 -0

index 07fb0d25fc15..e9c956535f97 100644
@@ -333,6 +333,8 @@ patternProperties:
     description: EBV Elektronik
   "^eckelmann,.*":
     description: Eckelmann AG
+  "^airoha,.*":
+    description: Airoha
   "^edt,.*":
     description: Emerging Display Technologies
   "^eeti,.*":

Signature · 1 line

2.25.1

Krzysztof Kozlowski

2021-09-07 11:13 UTC #2 lore raw

Re: [PATCH v2 1/5] dt-bindings: Add vendor prefix for Airoha

Quoted 15 lines · Bert Vermeulen

From: John Crispin <[email protected]>
Add vendor prefix "airoha" for Airoha.
Signed-off-by John Crispin <[email protected]>
Signed-off-by Bert Vermeulen <[email protected]>
---
 Documentation/devicetree/bindings/vendor-prefixes.yaml | 2 ++
 1 file changed, 2 insertions(+)
Documentation/devicetree/bindings/vendor-prefixes.yaml +0 -0
index 07fb0d25fc15..e9c956535f97 100644

Documentation/devicetree/bindings/vendor-prefixes.yaml patternProperties: · line 337

Quoted 5 lines

Documentation/devicetree/bindings/vendor-prefixes.yaml +2 -0

@@ -333,6 +333,8 @@ patternProperties:
     description: EBV Elektronik
   "^eckelmann,.*":
     description: Eckelmann AG
+  "^airoha,.*":
+    description: Airoha

Wrong ordering.

Best regards,
Krzysztof

Bert Vermeulen

author

2021-09-07 10:27 UTC #3 lore raw

PATCH v2 2/5 dt-bindings: arm: airoha: Add binding for EN7523 SoC and EVB

From: John Crispin <[email protected]>

Add devicetree binding for Airoha EN7523 SoC and evaluation board.

---
 .../devicetree/bindings/arm/airoha.yaml       | 27 +++++++++++++++++++
 1 file changed, 27 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/arm/airoha.yaml

Documentation/devicetree/bindings/arm/airoha.yaml new file +27 -0

new file mode 100644
index 000000000000..f2661ba81109
@@ -0,0 +1,27 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/arm/airoha.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Airoha SoC based Platforms Device Tree Bindings
+
+maintainers:
+  - Felix Fietkau <[email protected]>
+  - John Crispin <[email protected]>
+description: |
+  Boards with an Airoha SoC shall have the following properties.
+
+properties:
+  $nodename:
+    const: '/'
+  compatible:
+    oneOf:
+      - items:
+          - enum:
+              - airoha,en7523-evb
+          - const: airoha,en7523
+
+additionalProperties: true
+
+...

Signature · 1 line

2.25.1

Bert Vermeulen

author

2021-09-07 10:27 UTC #4 lore raw

PATCH v2 3/5 ARM: dts: Add basic support for Airoha EN7523

From: John Crispin <[email protected]>

Add basic support for Airoha EN7523, enough for booting to console.

The UART is basically 8250-compatible, except for the clock selection. A clock-frequency value is synthesized to get this to run at 115200 bps.

---
 arch/arm/boot/dts/Makefile       |   2 +
 arch/arm/boot/dts/en7523-evb.dts |  26 +++++++
 arch/arm/boot/dts/en7523.dtsi    | 114 +++++++++++++++++++++++++++++++
 3 files changed, 142 insertions(+)
 create mode 100644 arch/arm/boot/dts/en7523-evb.dts
 create mode 100644 arch/arm/boot/dts/en7523.dtsi

arch/arm/boot/dts/Makefile +2 -0

index 863347b6b65e..3525ace2d2e0 100644
@@ -174,6 +174,8 @@ dtb-$(CONFIG_ARCH_DAVINCI) += \
 	da850-lego-ev3.dtb
 dtb-$(CONFIG_ARCH_DIGICOLOR) += \
 	cx92755_equinox.dtb
+dtb-$(CONFIG_ARCH_AIROHA) += \
+	en7523-evb.dtb
 dtb-$(CONFIG_ARCH_EXYNOS3) += \
 	exynos3250-artik5-eval.dtb \
 	exynos3250-monk.dtb \

arch/arm/boot/dts/en7523-evb.dts new file +26 -0

new file mode 100644
index 000000000000..fa595b97bdd8
@@ -0,0 +1,26 @@
+// SPDX-License-Identifier: GPL-2.0
+/dts-v1/;
+
+/* Bootloader installs ATF here */
+/memreserve/ 0x80000000 0x80000;
+
+#include "en7523.dtsi"
+
+/ {
+	model = "Airoha EN7523 Evaluation Board";
+	compatible = "airoha,en7523-evb", "airoha,en7523";
+
+	aliases {
+		serial0 = &uart1;
+	};
+
+	chosen {
+		bootargs = "earlycon=uart8250,mmio32,0x1fbf0000 console=ttyS0,115200";
+		stdout-path = "serial0:115200n8";
+	};
+
+	memory@80000000 {
+		device_type = "memory";
+		reg = <0x80000000 0x20000000>;
+	};
+};

arch/arm/boot/dts/en7523.dtsi new file +114 -0

114 lines not on this page · raw message

Signature · 1 line

2.25.1

Bert Vermeulen

author

2021-09-07 10:30 UTC #5 lore raw

PATCH v2 4/5 ARM: Add basic support for Airoha EN7523 SoC

From: John Crispin <[email protected]>

EN7523 is an armv7 based silicon used inside broadband access type devices such as xPON and xDSL. It shares various silicon blocks with MediaTek silicon such as the MT7622.

0 - https://elixir.bootlin.com/linux/latest/source/arch/arm/mach-mstar/mstarv7.c#L61

---
 arch/arm/Kconfig | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

arch/arm/Kconfig +14 -0

index 82f908fa5676..4c210df05c77 100644
@@ -580,6 +580,20 @@ config ARCH_VIRT
 	select HAVE_ARM_ARCH_TIMER
 	select ARCH_SUPPORTS_BIG_ENDIAN
 
+config ARCH_AIROHA
+	bool "Airoha SoC Support"
+	depends on ARCH_MULTI_V7
+	select ARM_AMBA
+	select ARM_GIC
+	select ARM_GIC_V3
+	select ARM_DMA_USE_IOMMU
+	select ARM_PSCI
+	select HAVE_ARM_ARCH_TIMER
+	select IOMMU_DMA
+	select COMMON_CLK
+	help
+	  Support for Airoha EN7523 SoCs
+
 #
 # This is sorted alphabetically by mach-* pathname.  However, plat-*
 # Kconfigs may be included either alphabetically (according to the

Signature · 1 line

2.25.1

Daniel Palmer

2021-09-07 10:45 UTC #6 lore raw

Re: [PATCH v2 4/5] ARM: Add basic support for Airoha EN7523 SoC

Hi Bert,

Quoted 6 lines · Bert Vermeulen

From: John Crispin <[email protected]>
EN7523 is an armv7 based silicon used inside broadband access type devices such as xPON and xDSL. It shares various silicon blocks with MediaTek silicon such as the MT7622.

This is a Cortex A53 isn't it? So it's ARMv8. I thought the issue is that it's actually a 64bit system but you only have a 32bit bootloader, firmware etc?

Off-topic but related: Another MediaTek spin off, SigmaStar, seems to have done exactly the same thing. Cortex A53 chip running as a 32bit system to avoid having to fix their software. I'm interested to see if this makes it into arm or arm64. :)

Cheers,

Daniel

Arnd Bergmann

maintainer

2021-09-07 11:52 UTC #7 lore raw

Re: [PATCH v2 4/5] ARM: Add basic support for Airoha EN7523 SoC

Quoted 8 lines · Daniel Palmer

Quoted 6 lines · Bert Vermeulen
From: John Crispin <[email protected]>
EN7523 is an armv7 based silicon used inside broadband access type devices such as xPON and xDSL. It shares various silicon blocks with MediaTek silicon such as the MT7622.

Quoted 8 lines

This is a Cortex A53 isn't it? So it's ARMv8. I thought the issue is that it's actually a 64bit system but you only have a 32bit bootloader, firmware etc?
Off-topic but related: Another MediaTek spin off, SigmaStar, seems to have done exactly the same thing. Cortex A53 chip running as a 32bit system to avoid having to fix their software. I'm interested to see if this makes it into arm or arm64. :)

Maybe it's best to just add them to both at the same time? The boot loader situation might take a bit to work out, but in theory this should be fixable.

You can generally include .dtsi files from one in the other, as you can see from e.g. arch/arm64/boot/dts/broadcom/bcm2837-rpi-3-b.dts.

For new files, I think I would prefer having the .dts files in arm64 and including them from arch/arm/ rather than the other way round, but others may come up with a good reason to keep doing the reverse. This would help encourage the thought that running a 64-bit kernel is the better setup, rather than propagate the 32-bit kernel nonsense on 64-bit machines.

Arnd

Daniel Palmer

2021-09-07 12:28 UTC #8 lore raw

Re: [PATCH v2 4/5] ARM: Add basic support for Airoha EN7523 SoC

Hi Arnd,

Quoted 8 lines · Arnd Bergmann

Quoted 4 lines
Off-topic but related: Another MediaTek spin off, SigmaStar, seems to have done exactly the same thing. Cortex A53 chip running as a 32bit system to avoid having to fix their software. I'm interested to see if this makes it into arm or arm64. :)
Maybe it's best to just add them to both at the same time? The boot loader situation might take a bit to work out, but in theory this should be fixable.

I wonder how fixable it would be..

I haven't gotten a board with the chip in question (SSD268G) yet but from looking at some firmware binaries I can see that even u-boot is a 6 year old 32bit version.
As far as I can tell there's no PSCI, ATF etc that I think would be expected for an arm64 machine.
I think the broken memory controller is still there so somehow I'd need to get the heavy barrier to work in arm64. I haven't yet worked out if that's even possible.
I think they are advertising that it supports up to 2GB of DDR. So it's a hobbled 64bit capable system with highmem.

Putting most of the DT bits under arm64 even though it's so broken it'll only ever boot a 32bit kernel makes sense to me. Better than having lots of arm64 typical stuff like a newer GIC in a file under arm and confusing everyone that comes across it.

Cheers,

Daniel

Arnd Bergmann

maintainer

2021-09-07 14:12 UTC #9 lore raw

Re: [PATCH v2 4/5] ARM: Add basic support for Airoha EN7523 SoC

Quoted 10 lines · Daniel Palmer

Quoted 8 lines · Arnd Bergmann
Quoted 4 lines
Off-topic but related: Another MediaTek spin off, SigmaStar, seems to have done exactly the same thing. Cortex A53 chip running as a 32bit system to avoid having to fix their software. I'm interested to see if this makes it into arm or arm64. :)
Maybe it's best to just add them to both at the same time? The boot loader situation might take a bit to work out, but in theory this should be fixable.

Quoted 7 lines

I wonder how fixable it would be..
I haven't gotten a board with the chip in question (SSD268G) yet but from looking at some firmware binaries I can see that even u-boot is a 6 year old 32bit version.
As far as I can tell there's no PSCI, ATF etc that I think would be expected for an arm64 machine.

If the source code is available, creating a minimal PSCI implementation in u-boot should be possible, and it would make it work well for both 32-bit and 64-bit kernels. There is no need for ATF here.

Quoted 3 lines

I think the broken memory controller is still there so somehow I'd need to get the heavy barrier to work in arm64. I haven't yet worked out if that's even possible.

I think I missed that part of the discussion, or I forgot about it already. What is the issue you are referring to here?

Arnd

Daniel Palmer

2021-09-07 14:29 UTC #10 lore raw

Re: [PATCH v2 4/5] ARM: Add basic support for Airoha EN7523 SoC

Hi Arnd,

Quoted 5 lines · Arnd Bergmann

Quoted 3 lines
I think the broken memory controller is still there so somehow I'd need to get the heavy barrier to work in arm64. I haven't yet worked out if that's even possible.
I think I missed that part of the discussion, or I forgot about it already. What is the issue you are referring to here?

Sorry. I should have put a bit more context. This is for the SSD268G not the original target of this series. But a similar situation. The SSD268G (according to the decompiled device tree) is the same hardware as the MSTAR_V7 chips but with a Cortex A53 instead of the Cortex A7.
So it probably has the same memory controller as the MSTAR_V7 stuff and that memory controller is not coherent so it needs the kernel to make sure memory requests are flushed out to memory before DMA happens[0]. For arm I fixed that with the heavy mb callback. With arm64 I have no idea how to fix that.

I'm interested to see how this Airoha EN7523 series goes as if/when I push anything for the SSD268G it'll probably only be for a 32bit kernel.

Arnd Bergmann

maintainer

2021-09-07 15:22 UTC #11 lore raw

Re: [PATCH v2 4/5] ARM: Add basic support for Airoha EN7523 SoC

Quoted 8 lines · Daniel Palmer

Quoted 5 lines · Arnd Bergmann
Quoted 3 lines
I think the broken memory controller is still there so somehow I'd need to get the heavy barrier to work in arm64. I haven't yet worked out if that's even possible.
I think I missed that part of the discussion, or I forgot about it already. What is the issue you are referring to here?

Quoted 10 lines

Sorry. I should have put a bit more context. This is for the SSD268G not the original target of this series. But a similar situation. The SSD268G (according to the decompiled device tree) is the same hardware as the MSTAR_V7 chips but with a Cortex A53 instead of the Cortex A7.
So it probably has the same memory controller as the MSTAR_V7 stuff and that memory controller is not coherent so it needs the kernel to make sure memory requests are flushed out to memory before DMA happens[0]. For arm I fixed that with the heavy mb callback. With arm64 I have no idea how to fix that.

Ok, got it. I do remember the Mstar SoCs having this problem. My feeling is that this should be possible to implement on arm64 as well using an erratum fixup with a configuration option, and possibly dynamic patching to avoid the worst effects when the workaround is built into the kernel but not needed.

Whether this is acceptable or not is up to the arm64 architecture maintainers of course.

Arnd

Bert Vermeulen

author

2021-09-07 10:28 UTC #12 lore raw

PATCH v2 5/5 ARM: multi_v7_defconfig: Add support for Airoha EN7523 SoC

From: John Crispin <[email protected]>

This enables basic bootup support for the Airoha EN7523 SoC.