[PATCH v2 00/21] Add support for the Mobileye EyeQ5 SoC

From: Gregory CLEMENT
Date: Thu Nov 23 2023 - 10:26:56 EST


Hello,

The EyeQ5 SoC from Mobileye is based on the MIPS I6500 architecture
and features multiple controllers such as the classic UART, I2C, SPI,
as well as CAN-FD, PCIe, Octal/Quad SPI Flash interface, Gigabit
Ethernet, MIPI CSI-2, and eMMC 5.1. It also includes a Hardware
Security Module, Functional Safety Hardware, and MJPEG encoder.

One peculiarity of this SoC is that the physical address of the DDDR
exceeds 32 bits. Given that the architecture is 64 bits, this is not
an issue, but it requires some changes in how the mips64 is currently
managed during boot.

This second version comes a few weeks after the first one, because
there several iteration to support having kernel code outside kseg.

To build and test the
kernel, we need to run the following commands:

make 64r6el_defconfig BOARDS=eyeq5
make vmlinuz.itb

In order to get ride of the aliasing patch I got, I followed Jiaxun
Yang suggestion by splitting the memory in 2 part: low part under
512MB and high part beyond the 4GB. It allows to boot and run Linux on
the platform however as a side effect the number of pages used for
memmap passed from 512 to 8672 which is a huge consumption of
pages. Do you know if there is a way to reduce it ?

I also noticed that if the kernel can't be in kseg0 at all by using
low memory at 0x40000000, then I got the following message during
boot:

Run /init as init process
Unhandled kernel unaligned access[#1]:
CPU: 0 PID: 22 Comm: kcompactd0 Not tainted 6.7.0-rc1-00024-g7d48f10cb2bb-dirty #409
$ 0 : 0000000000000000 0000000000000001 0000000000000010 a80000080800e100
$ 4 : a8000008088fe758 00000000088fe758 0000000000000004 0000000000000002
$ 8 : 0000000000000089 0000000008fa0000 0000000000000000 0000000008ad0000
$12 : 00000000140000e1 000000001000001e 0000000000000000 0000000000000141
$16 : a80000080321fa30 0000000000000000 b88f553ba6dfc404 a8000008081bfe9c
$20 : a800000808ad0000 a8000008081c03e4 0000000000012488 a80000080907afb4
$24 : 0000000000000000 0000000008ad0000
$28 : a80000080321c000 a80000080321f950 0000000000000000 a80000080800dcd0
epc : a80000080800e104 emulate_load_store_insn+0x544/0xba0
ra : a80000080800dcd0 emulate_load_store_insn+0x110/0xba0
Status: 140000e3 KX SX UX KERNEL EXL IE
Cause : 80800410 (ExcCode 04)
BadVA : b88f553ba6dfc40b
PrId : 0001b028 (MIPS I6500)
Modules linked in:
Process kcompactd0 (pid: 22, threadinfo=(____ptrval____), task=(____ptrval____), tls=0000000000000000)
Stack : 0000000000000000 0000000000000000 00000000dc420010 a8afa5b0e1346800
0000000000012488 a80000080907af80 a80000080321fd28 a800000808acfb80
a800000808ad0000 0000000000000000 a80000080321fa30 a80000080800e90c
0000000000000000 0000000000000000 0000000000000000 0000000000000000
0000000000000000 a8afa5b0e1346800 0000000000000000 a80000080907afb4
0000000000012488 a80000080907af80 a80000080321fd28 a800000809078d80
0000000000000000 0000000000000000 0000000000000000 a800000808003174
0000000000000000 0000000000000001 b88f553ba6dfc3f4 f91f7fb9d6d87a3d
0000000000000002 fffffffffffffffc 0000000000000080 0000000008b90000
0000000000000089 0000000008fc0000 0000000000000000 0000000000000000
...
Call Trace:
[<a80000080800e104>] emulate_load_store_insn+0x544/0xba0
[<a80000080800e90c>] do_ade+0x1ac/0x1520
[<a800000808003174>] handle_adel_int+0x30/0x3c

Code: 3c03a800 cbffff4d 24020010 <205100f0> 82510007 92410006 00118a38 02218825 92410005

---[ end trace 0000000000000000 ]---

But then I don't see other error when running the system.
So I don't know if this is a "real" error and how to fix it.

Changelog:
v1 -> v2

- Added reviewed-by and acked-by tags

- Fix typos reported

- In patch 15 use 'img' vendor string instead of mti

- In patch 16 modify licence

- In patch 17 give more explanations about the block usage.

- In patch 18, remove _ in node names, don't use anymore
CONFIG_BUILTIN_DTB in Makefile, remove macro, modify licence.

- In patch 19 remove most of the bootargs and only keeps earlycon. I
also split the memory in 2 part in the device tree.

- Integrate the series from Jiaxun Yang
https://lore.kernel.org/linux-mips/20231027221106.405666-1-jiaxun.yang@xxxxxxxxxxx/

They are patches 2 to 6 and 8 to 12

Then I added patch 7 to fix the cache issue visible on the Mobielye
platform, I also add patch 13 to improve warning message when ebase
doesn't belong to KSEG0

Regards,

Gregory

Gregory CLEMENT (11):
MIPS: compressed: Use correct instruction for 64 bit code
MIPS: Fix cache issue with mips_cps_core_entry
MIPS: traps: Give more explanations if ebase doesn't belong to KSEG0
dt-bindings: Add vendor prefix for Mobileye Vision Technologies Ltd.
dt-bindings: mips: cpu: Add I-Class I6500 Multiprocessor Core
dt-bindings: mips: Add bindings for Mobileye SoCs
dt-bindings: mfd: syscon: Document EyeQ5 OLB
MIPS: mobileye: Add EyeQ5 dtsi
MIPS: mobileye: Add EPM5 device tree
MIPS: generic: Add support for Mobileye EyeQ5
MAINTAINERS: Add entry for Mobileye MIPS SoCs

Jiaxun Yang (10):
MIPS: Export higher/highest relocation functions in uasm
MIPS: spaces: Define a couple of handy macros
MIPS: genex: Fix except_vec_vi for kernel in XKPHYS
MIPS: Fix set_uncached_handler for ebase in XKPHYS
MIPS: Refactor mips_cps_core_entry implementation
MIPS: Allow kernel base to be set from Kconfig for all platforms
MIPS: traps: Handle CPU with non standard vint offset
MIPS: Avoid unnecessary reservation of exception space
MIPS: traps: Enhance memblock ebase allocation process
MIPS: Get rid of CONFIG_NO_EXCEPT_FILL

.../devicetree/bindings/mfd/syscon.yaml | 1 +
.../devicetree/bindings/mips/cpus.yaml | 1 +
.../devicetree/bindings/mips/mobileye.yaml | 32 ++
.../devicetree/bindings/vendor-prefixes.yaml | 2 +
MAINTAINERS | 12 +
arch/mips/Kconfig | 26 +-
arch/mips/boot/compressed/head.S | 4 +-
arch/mips/boot/dts/Makefile | 1 +
arch/mips/boot/dts/mobileye/Makefile | 4 +
arch/mips/boot/dts/mobileye/eyeq5-epm5.dts | 24 ++
.../boot/dts/mobileye/eyeq5-fixed-clocks.dtsi | 292 ++++++++++++++++++
arch/mips/boot/dts/mobileye/eyeq5.dtsi | 134 ++++++++
arch/mips/configs/generic/board-eyeq5.config | 43 +++
arch/mips/generic/Kconfig | 15 +
arch/mips/generic/Platform | 2 +
arch/mips/generic/board-epm5.its.S | 24 ++
arch/mips/include/asm/addrspace.h | 5 +
arch/mips/include/asm/mach-generic/spaces.h | 5 +-
arch/mips/include/asm/mips-cm.h | 1 +
arch/mips/include/asm/smp-cps.h | 4 +-
arch/mips/include/asm/traps.h | 1 -
arch/mips/include/asm/uasm.h | 2 +
arch/mips/kernel/cps-vec.S | 110 +++----
arch/mips/kernel/cpu-probe.c | 5 -
arch/mips/kernel/cpu-r3k-probe.c | 2 -
arch/mips/kernel/genex.S | 19 +-
arch/mips/kernel/head.S | 7 +-
arch/mips/kernel/smp-cps.c | 171 ++++++++--
arch/mips/kernel/traps.c | 90 ++++--
arch/mips/mm/uasm.c | 6 +-
30 files changed, 890 insertions(+), 155 deletions(-)
create mode 100644 Documentation/devicetree/bindings/mips/mobileye.yaml
create mode 100644 arch/mips/boot/dts/mobileye/Makefile
create mode 100644 arch/mips/boot/dts/mobileye/eyeq5-epm5.dts
create mode 100644 arch/mips/boot/dts/mobileye/eyeq5-fixed-clocks.dtsi
create mode 100644 arch/mips/boot/dts/mobileye/eyeq5.dtsi
create mode 100644 arch/mips/configs/generic/board-eyeq5.config
create mode 100644 arch/mips/generic/board-epm5.its.S

--
2.42.0