[PATCH V5 00/10] irqchip: Add LoongArch-related irqchip drivers
From: Huacai Chen
Date: Thu Sep 16 2021 - 08:32:43 EST
LoongArch is a new RISC ISA, which is a bit like MIPS or RISC-V.
LoongArch includes a reduced 32-bit version (LA32R), a standard 32-bit
version (LA32S) and a 64-bit version (LA64). LoongArch use ACPI as its
boot protocol LoongArch-specific interrupt controllers (similar to APIC)
are already added in the next revision of ACPI Specification (current
revision is 6.4).
Currently, LoongArch based processors (e.g. Loongson-3A5000) can only
work together with LS7A chipsets. The irq chips in LoongArch computers
include CPUINTC (CPU Core Interrupt Controller), LIOINTC (Legacy I/O
Interrupt Controller), EIOINTC (Extended I/O Interrupt Controller),
HTVECINTC (Hyper-Transport Vector Interrupt Controller), PCH-PIC (Main
Interrupt Controller in LS7A chipset), PCH-LPC (LPC Interrupt Controller
in LS7A chipset) and PCH-MSI (MSI Interrupt Controller).
CPUINTC is a per-core controller (in CPU), LIOINTC/EIOINTC/HTVECINTC are
per-package controllers (in CPU), while PCH-PIC/PCH-LPC/PCH-MSI are all
controllers out of CPU (i.e., in chipsets). These controllers (in other
words, irqchips) are linked in a hierarchy, and there are two models of
hierarchy (legacy model and extended model).
Legacy IRQ model:
In this model, the IPI (Inter-Processor Interrupt) and CPU Local Timer
interrupt go to CPUINTC directly, CPU UARTS interrupts go to LIOINTC,
while all other devices interrupts go to PCH-PIC/PCH-LPC/PCH-MSI and
gathered by HTVECINTC, and then go to LIOINTC, and then CPUINTC.
+---------------------------------------------+
| |
| +-----+ +---------+ +-------+ |
| | IPI | --> | CPUINTC | <-- | Timer | |
| +-----+ +---------+ +-------+ |
| ^ |
| | |
| +---------+ +-------+ |
| | LIOINTC | <-- | UARTs | |
| +---------+ +-------+ |
| ^ |
| | |
| +-----------+ |
| | HTVECINTC | |
| +-----------+ |
| ^ ^ |
| | | |
| +---------+ +---------+ |
| | PCH-PIC | | PCH-MSI | |
| +---------+ +---------+ |
| ^ ^ ^ |
| | | | |
| +---------+ +---------+ +---------+ |
| | PCH-LPC | | Devices | | Devices | |
| +---------+ +---------+ +---------+ |
| ^ |
| | |
| +---------+ |
| | Devices | |
| +---------+ |
| |
| |
+---------------------------------------------+
Extended IRQ model:
In this model, the IPI (Inter-Processor Interrupt) and CPU Local Timer
interrupt go to CPUINTC directly, CPU UARTS interrupts go to LIOINTC,
while all other devices interrupts go to PCH-PIC/PCH-LPC/PCH-MSI and
gathered by EIOINTC, and then go to to CPUINTC directly.
+--------------------------------------------------------+
| |
| +-----+ +---------+ +-------+ |
| | IPI | --> | CPUINTC | <-- | Timer | |
| +-----+ +---------+ +-------+ |
| ^ ^ |
| | | |
| +---------+ +---------+ +-------+ |
| | EIOINTC | | LIOINTC | <-- | UARTs | |
| +---------+ +---------+ +-------+ |
| ^ ^ |
| | | |
| +---------+ +---------+ |
| | PCH-PIC | | PCH-MSI | |
| +---------+ +---------+ |
| ^ ^ ^ |
| | | | |
| +---------+ +---------+ +---------+ |
| | PCH-LPC | | Devices | | Devices | |
| +---------+ +---------+ +---------+ |
| ^ |
| | |
| +---------+ |
| | Devices | |
| +---------+ |
| |
| |
+--------------------------------------------------------+
This patchset adds some irqchip drivers for LoongArch, it is preparing
to add LoongArch support in mainline kernel, we can see a snapshot here:
https://github.com/loongson/linux/tree/loongarch-next
Cross-compile tool chain to build kernel:
https://github.com/loongson/build-tools/releases
Loongson and LoongArch documentations:
https://github.com/loongson/LoongArch-Documentation
LoongArch-specific interrupt controllers:
https://mantis.uefi.org/mantis/view.php?id=2203
V1 -> V2:
1, Remove queued patches;
2, Move common logic of DT/ACPI probing to common functions;
3, Split .suspend()/.resume() functions to separate patches.
V2 -> V3:
1, Fix a bug for loongson-pch-pic probe;
2, Some minor improvements for LPC controller.
V3 -> V4:
1, Rework the CPU interrupt controller driver;
2, Some minor improvements for other controllers.
V4 -> V5:
1, Add a description of LoonArch's IRQ model;
2, Support multiple EIOINTCs in one system;
3, Some minor improvements for other controllers.
Huacai Chen:
irqchip: Adjust Kconfig for Loongson.
irqchip/loongson-pch-pic: Add ACPI init support.
irqchip/loongson-pch-pic: Add suspend/resume support.
irqchip/loongson-pch-msi: Add ACPI init support.
irqchip/loongson-htvec: Add ACPI init support.
irqchip/loongson-htvec: Add suspend/resume support.
irqchip/loongson-liointc: Add ACPI init support.
irqchip: Add LoongArch CPU interrupt controller support.
irqchip: Add Loongson Extended I/O interrupt controller.
irqchip: Add Loongson PCH LPC controller support.
Signed-off-by: Huacai Chen <chenhuacai@xxxxxxxxxxx>
---
drivers/irqchip/Kconfig | 37 +++-
drivers/irqchip/Makefile | 3 +
drivers/irqchip/irq-loongarch-cpu.c | 89 +++++++++
drivers/irqchip/irq-loongson-eiointc.c | 331 +++++++++++++++++++++++++++++++++
drivers/irqchip/irq-loongson-htvec.c | 142 ++++++++++----
drivers/irqchip/irq-loongson-liointc.c | 198 ++++++++++++--------
drivers/irqchip/irq-loongson-pch-lpc.c | 203 ++++++++++++++++++++
drivers/irqchip/irq-loongson-pch-msi.c | 119 +++++++-----
drivers/irqchip/irq-loongson-pch-pic.c | 152 ++++++++++++---
include/linux/cpuhotplug.h | 1 +
10 files changed, 1087 insertions(+), 188 deletions(-)
create mode 100644 drivers/irqchip/irq-loongarch-cpu.c
create mode 100644 drivers/irqchip/irq-loongson-eiointc.c
create mode 100644 drivers/irqchip/irq-loongson-pch-lpc.c
--
2.27.0