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authorLinus Torvalds <torvalds@linux-foundation.org>2022-06-03 14:09:21 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2022-06-03 14:09:21 -0700
commitc6f2f3e2c80e975804360665d973211e4d9390cb (patch)
tree8471e582551d1f37722ef507ea67b12647a23f5a /Documentation
parent21873bd66b6e6040d95d0a33525ea6933bdc6c71 (diff)
parent8be4493119b0aedf7dd61e1ca520fb398537b53e (diff)
downloadlinux-c6f2f3e2c80e975804360665d973211e4d9390cb.tar.bz2
Merge tag 'loongarch-5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic
Pull initial Loongarch architecture code from Arnd Bergmann: "This is the majority of the loongarch architecture code, including the final system call interface and all core functionality. It still misses three sets of peripheral but vital patches to add support for other subsystems, which have yet to pass review: - The drivers/firmware/efi stub for booting from a standard UEFI firmware implementation. Both the original custom boot interface and a draft implementation of the EFI stub did not make it, so it is currently impossible to boot the kernel, until the loongarch specific portions get accepted into the UEFI subsystem - The drivers/irqchip/irq-loongson-*.c drivers are shared with the the MIPS port, but currently lack support for ACPI based booting, which will get merged through the irqchip subsystem. - Similarly, the drivers/pci/controller/pci-loongson.c needs to be modified for ACPI support, which will be merged through the PCI subsystem. While the port cannot actually be used before all the above are merged, having it in 5.19 helps to establish the user space ABI for the libc ports to build on, and to help any treewide changes in the mainline kernel get applied here as well. A gcc-12 based tool chains for build testing is now included in https://mirrors.edge.kernel.org/pub/tools/crosstool/" Original description from Huacai Chen: "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). This patchset is adding basic LoongArch support in mainline kernel, we can see a complete snapshot here: https://github.com/loongson/linux/tree/loongarch-next https://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson.git/log/?h=loongarch-next Cross-compile tool chain to build kernel: https://github.com/loongson/build-tools/releases/download/2021.12.21/loongarch64-clfs-2022-03-03-cross-tools-gcc-glibc.tar.xz A CLFS-based Linux distro: https://github.com/loongson/build-tools/releases/download/2021.12.21/loongarch64-clfs-system-2022-03-03.tar.bz2 Open-source tool chain which is under review (Binutils and Gcc are already upstream): https://github.com/loongson/binutils-gdb/tree/upstream_v3.1 https://github.com/loongson/gcc/tree/loongarch_upstream_v6.3 https://github.com/loongson/glibc/tree/loongarch_2_35_dev_v2.2 Loongson and LoongArch documentations: https://github.com/loongson/LoongArch-Documentation LoongArch-specific interrupt controllers: https://mantis.uefi.org/mantis/view.php?id=2203 https://mantis.uefi.org/mantis/view.php?id=2313" Link: https://lore.kernel.org/lkml/20220603072053.35005-1-chenhuacai@loongson.cn/ * tag 'loongarch-5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic: (24 commits) MAINTAINERS: Add maintainer information for LoongArch LoongArch: Add Loongson-3 default config file LoongArch: Add Non-Uniform Memory Access (NUMA) support LoongArch: Add multi-processor (SMP) support LoongArch: Add VDSO and VSYSCALL support LoongArch: Add some library functions LoongArch: Add misc common routines LoongArch: Add ELF and module support LoongArch: Add signal handling support LoongArch: Add system call support LoongArch: Add memory management LoongArch: Add process management LoongArch: Add exception/interrupt handling LoongArch: Add boot and setup routines LoongArch: Add other common headers LoongArch: Add atomic/locking headers LoongArch: Add CPU definition headers LoongArch: Add build infrastructure LoongArch: Add writecombine support for drm LoongArch: Add ELF-related definitions ...
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/arch.rst1
-rw-r--r--Documentation/loongarch/features.rst3
-rw-r--r--Documentation/loongarch/index.rst21
-rw-r--r--Documentation/loongarch/introduction.rst387
-rw-r--r--Documentation/loongarch/irq-chip-model.rst156
-rw-r--r--Documentation/translations/zh_CN/index.rst1
-rw-r--r--Documentation/translations/zh_CN/loongarch/features.rst8
-rw-r--r--Documentation/translations/zh_CN/loongarch/index.rst26
-rw-r--r--Documentation/translations/zh_CN/loongarch/introduction.rst351
-rw-r--r--Documentation/translations/zh_CN/loongarch/irq-chip-model.rst155
10 files changed, 1109 insertions, 0 deletions
diff --git a/Documentation/arch.rst b/Documentation/arch.rst
index 14bcd8294b93..41a66a8b38e4 100644
--- a/Documentation/arch.rst
+++ b/Documentation/arch.rst
@@ -13,6 +13,7 @@ implementation.
arm/index
arm64/index
ia64/index
+ loongarch/index
m68k/index
mips/index
nios2/index
diff --git a/Documentation/loongarch/features.rst b/Documentation/loongarch/features.rst
new file mode 100644
index 000000000000..ebacade3ea45
--- /dev/null
+++ b/Documentation/loongarch/features.rst
@@ -0,0 +1,3 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+.. kernel-feat:: $srctree/Documentation/features loongarch
diff --git a/Documentation/loongarch/index.rst b/Documentation/loongarch/index.rst
new file mode 100644
index 000000000000..aaba648db907
--- /dev/null
+++ b/Documentation/loongarch/index.rst
@@ -0,0 +1,21 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+======================
+LoongArch Architecture
+======================
+
+.. toctree::
+ :maxdepth: 2
+ :numbered:
+
+ introduction
+ irq-chip-model
+
+ features
+
+.. only:: subproject and html
+
+ Indices
+ =======
+
+ * :ref:`genindex`
diff --git a/Documentation/loongarch/introduction.rst b/Documentation/loongarch/introduction.rst
new file mode 100644
index 000000000000..2bf40ad370df
--- /dev/null
+++ b/Documentation/loongarch/introduction.rst
@@ -0,0 +1,387 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+=========================
+Introduction to LoongArch
+=========================
+
+LoongArch is a new RISC ISA, which is a bit like MIPS or RISC-V. There are
+currently 3 variants: a reduced 32-bit version (LA32R), a standard 32-bit
+version (LA32S) and a 64-bit version (LA64). There are 4 privilege levels
+(PLVs) defined in LoongArch: PLV0~PLV3, from high to low. Kernel runs at PLV0
+while applications run at PLV3. This document introduces the registers, basic
+instruction set, virtual memory and some other topics of LoongArch.
+
+Registers
+=========
+
+LoongArch registers include general purpose registers (GPRs), floating point
+registers (FPRs), vector registers (VRs) and control status registers (CSRs)
+used in privileged mode (PLV0).
+
+GPRs
+----
+
+LoongArch has 32 GPRs ( ``$r0`` ~ ``$r31`` ); each one is 32-bit wide in LA32
+and 64-bit wide in LA64. ``$r0`` is hard-wired to zero, and the other registers
+are not architecturally special. (Except ``$r1``, which is hard-wired as the
+link register of the BL instruction.)
+
+The kernel uses a variant of the LoongArch register convention, as described in
+the LoongArch ELF psABI spec, in :ref:`References <loongarch-references>`:
+
+================= =============== =================== ============
+Name Alias Usage Preserved
+ across calls
+================= =============== =================== ============
+``$r0`` ``$zero`` Constant zero Unused
+``$r1`` ``$ra`` Return address No
+``$r2`` ``$tp`` TLS/Thread pointer Unused
+``$r3`` ``$sp`` Stack pointer Yes
+``$r4``-``$r11`` ``$a0``-``$a7`` Argument registers No
+``$r4``-``$r5`` ``$v0``-``$v1`` Return value No
+``$r12``-``$r20`` ``$t0``-``$t8`` Temp registers No
+``$r21`` ``$u0`` Percpu base address Unused
+``$r22`` ``$fp`` Frame pointer Yes
+``$r23``-``$r31`` ``$s0``-``$s8`` Static registers Yes
+================= =============== =================== ============
+
+Note: The register ``$r21`` is reserved in the ELF psABI, but used by the Linux
+kernel for storing the percpu base address. It normally has no ABI name, but is
+called ``$u0`` in the kernel. You may also see ``$v0`` or ``$v1`` in some old code,
+however they are deprecated aliases of ``$a0`` and ``$a1`` respectively.
+
+FPRs
+----
+
+LoongArch has 32 FPRs ( ``$f0`` ~ ``$f31`` ) when FPU is present. Each one is
+64-bit wide on the LA64 cores.
+
+The floating-point register convention is the same as described in the
+LoongArch ELF psABI spec:
+
+================= ================== =================== ============
+Name Alias Usage Preserved
+ across calls
+================= ================== =================== ============
+``$f0``-``$f7`` ``$fa0``-``$fa7`` Argument registers No
+``$f0``-``$f1`` ``$fv0``-``$fv1`` Return value No
+``$f8``-``$f23`` ``$ft0``-``$ft15`` Temp registers No
+``$f24``-``$f31`` ``$fs0``-``$fs7`` Static registers Yes
+================= ================== =================== ============
+
+Note: You may see ``$fv0`` or ``$fv1`` in some old code, however they are deprecated
+aliases of ``$fa0`` and ``$fa1`` respectively.
+
+VRs
+----
+
+There are currently 2 vector extensions to LoongArch:
+
+- LSX (Loongson SIMD eXtension) with 128-bit vectors,
+- LASX (Loongson Advanced SIMD eXtension) with 256-bit vectors.
+
+LSX brings ``$v0`` ~ ``$v31`` while LASX brings ``$x0`` ~ ``$x31`` as the vector
+registers.
+
+The VRs overlap with FPRs: for example, on a core implementing LSX and LASX,
+the lower 128 bits of ``$x0`` is shared with ``$v0``, and the lower 64 bits of
+``$v0`` is shared with ``$f0``; same with all other VRs.
+
+CSRs
+----
+
+CSRs can only be accessed from privileged mode (PLV0):
+
+================= ===================================== ==============
+Address Full Name Abbrev Name
+================= ===================================== ==============
+0x0 Current Mode Information CRMD
+0x1 Pre-exception Mode Information PRMD
+0x2 Extension Unit Enable EUEN
+0x3 Miscellaneous Control MISC
+0x4 Exception Configuration ECFG
+0x5 Exception Status ESTAT
+0x6 Exception Return Address ERA
+0x7 Bad (Faulting) Virtual Address BADV
+0x8 Bad (Faulting) Instruction Word BADI
+0xC Exception Entrypoint Address EENTRY
+0x10 TLB Index TLBIDX
+0x11 TLB Entry High-order Bits TLBEHI
+0x12 TLB Entry Low-order Bits 0 TLBELO0
+0x13 TLB Entry Low-order Bits 1 TLBELO1
+0x18 Address Space Identifier ASID
+0x19 Page Global Directory Address for PGDL
+ Lower-half Address Space
+0x1A Page Global Directory Address for PGDH
+ Higher-half Address Space
+0x1B Page Global Directory Address PGD
+0x1C Page Walk Control for Lower- PWCL
+ half Address Space
+0x1D Page Walk Control for Higher- PWCH
+ half Address Space
+0x1E STLB Page Size STLBPS
+0x1F Reduced Virtual Address Configuration RVACFG
+0x20 CPU Identifier CPUID
+0x21 Privileged Resource Configuration 1 PRCFG1
+0x22 Privileged Resource Configuration 2 PRCFG2
+0x23 Privileged Resource Configuration 3 PRCFG3
+0x30+n (0≤n≤15) Saved Data register SAVEn
+0x40 Timer Identifier TID
+0x41 Timer Configuration TCFG
+0x42 Timer Value TVAL
+0x43 Compensation of Timer Count CNTC
+0x44 Timer Interrupt Clearing TICLR
+0x60 LLBit Control LLBCTL
+0x80 Implementation-specific Control 1 IMPCTL1
+0x81 Implementation-specific Control 2 IMPCTL2
+0x88 TLB Refill Exception Entrypoint TLBRENTRY
+ Address
+0x89 TLB Refill Exception BAD (Faulting) TLBRBADV
+ Virtual Address
+0x8A TLB Refill Exception Return Address TLBRERA
+0x8B TLB Refill Exception Saved Data TLBRSAVE
+ Register
+0x8C TLB Refill Exception Entry Low-order TLBRELO0
+ Bits 0
+0x8D TLB Refill Exception Entry Low-order TLBRELO1
+ Bits 1
+0x8E TLB Refill Exception Entry High-order TLBEHI
+ Bits
+0x8F TLB Refill Exception Pre-exception TLBRPRMD
+ Mode Information
+0x90 Machine Error Control MERRCTL
+0x91 Machine Error Information 1 MERRINFO1
+0x92 Machine Error Information 2 MERRINFO2
+0x93 Machine Error Exception Entrypoint MERRENTRY
+ Address
+0x94 Machine Error Exception Return MERRERA
+ Address
+0x95 Machine Error Exception Saved Data MERRSAVE
+ Register
+0x98 Cache TAGs CTAG
+0x180+n (0≤n≤3) Direct Mapping Configuration Window n DMWn
+0x200+2n (0≤n≤31) Performance Monitor Configuration n PMCFGn
+0x201+2n (0≤n≤31) Performance Monitor Overall Counter n PMCNTn
+0x300 Memory Load/Store WatchPoint MWPC
+ Overall Control
+0x301 Memory Load/Store WatchPoint MWPS
+ Overall Status
+0x310+8n (0≤n≤7) Memory Load/Store WatchPoint n MWPnCFG1
+ Configuration 1
+0x311+8n (0≤n≤7) Memory Load/Store WatchPoint n MWPnCFG2
+ Configuration 2
+0x312+8n (0≤n≤7) Memory Load/Store WatchPoint n MWPnCFG3
+ Configuration 3
+0x313+8n (0≤n≤7) Memory Load/Store WatchPoint n MWPnCFG4
+ Configuration 4
+0x380 Instruction Fetch WatchPoint FWPC
+ Overall Control
+0x381 Instruction Fetch WatchPoint FWPS
+ Overall Status
+0x390+8n (0≤n≤7) Instruction Fetch WatchPoint n FWPnCFG1
+ Configuration 1
+0x391+8n (0≤n≤7) Instruction Fetch WatchPoint n FWPnCFG2
+ Configuration 2
+0x392+8n (0≤n≤7) Instruction Fetch WatchPoint n FWPnCFG3
+ Configuration 3
+0x393+8n (0≤n≤7) Instruction Fetch WatchPoint n FWPnCFG4
+ Configuration 4
+0x500 Debug Register DBG
+0x501 Debug Exception Return Address DERA
+0x502 Debug Exception Saved Data Register DSAVE
+================= ===================================== ==============
+
+ERA, TLBRERA, MERRERA and DERA are sometimes also known as EPC, TLBREPC, MERREPC
+and DEPC respectively.
+
+Basic Instruction Set
+=====================
+
+Instruction formats
+-------------------
+
+LoongArch instructions are 32 bits wide, belonging to 9 basic instruction
+formats (and variants of them):
+
+=========== ==========================
+Format name Composition
+=========== ==========================
+2R Opcode + Rj + Rd
+3R Opcode + Rk + Rj + Rd
+4R Opcode + Ra + Rk + Rj + Rd
+2RI8 Opcode + I8 + Rj + Rd
+2RI12 Opcode + I12 + Rj + Rd
+2RI14 Opcode + I14 + Rj + Rd
+2RI16 Opcode + I16 + Rj + Rd
+1RI21 Opcode + I21L + Rj + I21H
+I26 Opcode + I26L + I26H
+=========== ==========================
+
+Rd is the destination register operand, while Rj, Rk and Ra ("a" stands for
+"additional") are the source register operands. I8/I12/I16/I21/I26 are
+immediate operands of respective width. The longer I21 and I26 are stored
+in separate higher and lower parts in the instruction word, denoted by the "L"
+and "H" suffixes.
+
+List of Instructions
+--------------------
+
+For brevity, only instruction names (mnemonics) are listed here; please see the
+:ref:`References <loongarch-references>` for details.
+
+
+1. Arithmetic Instructions::
+
+ ADD.W SUB.W ADDI.W ADD.D SUB.D ADDI.D
+ SLT SLTU SLTI SLTUI
+ AND OR NOR XOR ANDN ORN ANDI ORI XORI
+ MUL.W MULH.W MULH.WU DIV.W DIV.WU MOD.W MOD.WU
+ MUL.D MULH.D MULH.DU DIV.D DIV.DU MOD.D MOD.DU
+ PCADDI PCADDU12I PCADDU18I
+ LU12I.W LU32I.D LU52I.D ADDU16I.D
+
+2. Bit-shift Instructions::
+
+ SLL.W SRL.W SRA.W ROTR.W SLLI.W SRLI.W SRAI.W ROTRI.W
+ SLL.D SRL.D SRA.D ROTR.D SLLI.D SRLI.D SRAI.D ROTRI.D
+
+3. Bit-manipulation Instructions::
+
+ EXT.W.B EXT.W.H CLO.W CLO.D SLZ.W CLZ.D CTO.W CTO.D CTZ.W CTZ.D
+ BYTEPICK.W BYTEPICK.D BSTRINS.W BSTRINS.D BSTRPICK.W BSTRPICK.D
+ REVB.2H REVB.4H REVB.2W REVB.D REVH.2W REVH.D BITREV.4B BITREV.8B BITREV.W BITREV.D
+ MASKEQZ MASKNEZ
+
+4. Branch Instructions::
+
+ BEQ BNE BLT BGE BLTU BGEU BEQZ BNEZ B BL JIRL
+
+5. Load/Store Instructions::
+
+ LD.B LD.BU LD.H LD.HU LD.W LD.WU LD.D ST.B ST.H ST.W ST.D
+ LDX.B LDX.BU LDX.H LDX.HU LDX.W LDX.WU LDX.D STX.B STX.H STX.W STX.D
+ LDPTR.W LDPTR.D STPTR.W STPTR.D
+ PRELD PRELDX
+
+6. Atomic Operation Instructions::
+
+ LL.W SC.W LL.D SC.D
+ AMSWAP.W AMSWAP.D AMADD.W AMADD.D AMAND.W AMAND.D AMOR.W AMOR.D AMXOR.W AMXOR.D
+ AMMAX.W AMMAX.D AMMIN.W AMMIN.D
+
+7. Barrier Instructions::
+
+ IBAR DBAR
+
+8. Special Instructions::
+
+ SYSCALL BREAK CPUCFG NOP IDLE ERTN(ERET) DBCL(DBGCALL) RDTIMEL.W RDTIMEH.W RDTIME.D
+ ASRTLE.D ASRTGT.D
+
+9. Privileged Instructions::
+
+ CSRRD CSRWR CSRXCHG
+ IOCSRRD.B IOCSRRD.H IOCSRRD.W IOCSRRD.D IOCSRWR.B IOCSRWR.H IOCSRWR.W IOCSRWR.D
+ CACOP TLBP(TLBSRCH) TLBRD TLBWR TLBFILL TLBCLR TLBFLUSH INVTLB LDDIR LDPTE
+
+Virtual Memory
+==============
+
+LoongArch supports direct-mapped virtual memory and page-mapped virtual memory.
+
+Direct-mapped virtual memory is configured by CSR.DMWn (n=0~3), it has a simple
+relationship between virtual address (VA) and physical address (PA)::
+
+ VA = PA + FixedOffset
+
+Page-mapped virtual memory has arbitrary relationship between VA and PA, which
+is recorded in TLB and page tables. LoongArch's TLB includes a fully-associative
+MTLB (Multiple Page Size TLB) and set-associative STLB (Single Page Size TLB).
+
+By default, the whole virtual address space of LA32 is configured like this:
+
+============ =========================== =============================
+Name Address Range Attributes
+============ =========================== =============================
+``UVRANGE`` ``0x00000000 - 0x7FFFFFFF`` Page-mapped, Cached, PLV0~3
+``KPRANGE0`` ``0x80000000 - 0x9FFFFFFF`` Direct-mapped, Uncached, PLV0
+``KPRANGE1`` ``0xA0000000 - 0xBFFFFFFF`` Direct-mapped, Cached, PLV0
+``KVRANGE`` ``0xC0000000 - 0xFFFFFFFF`` Page-mapped, Cached, PLV0
+============ =========================== =============================
+
+User mode (PLV3) can only access UVRANGE. For direct-mapped KPRANGE0 and
+KPRANGE1, PA is equal to VA with bit30~31 cleared. For example, the uncached
+direct-mapped VA of 0x00001000 is 0x80001000, and the cached direct-mapped
+VA of 0x00001000 is 0xA0001000.
+
+By default, the whole virtual address space of LA64 is configured like this:
+
+============ ====================== ======================================
+Name Address Range Attributes
+============ ====================== ======================================
+``XUVRANGE`` ``0x0000000000000000 - Page-mapped, Cached, PLV0~3
+ 0x3FFFFFFFFFFFFFFF``
+``XSPRANGE`` ``0x4000000000000000 - Direct-mapped, Cached / Uncached, PLV0
+ 0x7FFFFFFFFFFFFFFF``
+``XKPRANGE`` ``0x8000000000000000 - Direct-mapped, Cached / Uncached, PLV0
+ 0xBFFFFFFFFFFFFFFF``
+``XKVRANGE`` ``0xC000000000000000 - Page-mapped, Cached, PLV0
+ 0xFFFFFFFFFFFFFFFF``
+============ ====================== ======================================
+
+User mode (PLV3) can only access XUVRANGE. For direct-mapped XSPRANGE and
+XKPRANGE, PA is equal to VA with bits 60~63 cleared, and the cache attribute
+is configured by bits 60~61 in VA: 0 is for strongly-ordered uncached, 1 is
+for coherent cached, and 2 is for weakly-ordered uncached.
+
+Currently we only use XKPRANGE for direct mapping and XSPRANGE is reserved.
+
+To put this in action: the strongly-ordered uncached direct-mapped VA (in
+XKPRANGE) of 0x00000000_00001000 is 0x80000000_00001000, the coherent cached
+direct-mapped VA (in XKPRANGE) of 0x00000000_00001000 is 0x90000000_00001000,
+and the weakly-ordered uncached direct-mapped VA (in XKPRANGE) of 0x00000000
+_00001000 is 0xA0000000_00001000.
+
+Relationship of Loongson and LoongArch
+======================================
+
+LoongArch is a RISC ISA which is different from any other existing ones, while
+Loongson is a family of processors. Loongson includes 3 series: Loongson-1 is
+the 32-bit processor series, Loongson-2 is the low-end 64-bit processor series,
+and Loongson-3 is the high-end 64-bit processor series. Old Loongson is based on
+MIPS, while New Loongson is based on LoongArch. Take Loongson-3 as an example:
+Loongson-3A1000/3B1500/3A2000/3A3000/3A4000 are MIPS-compatible, while Loongson-
+3A5000 (and future revisions) are all based on LoongArch.
+
+.. _loongarch-references:
+
+References
+==========
+
+Official web site of Loongson Technology Corp. Ltd.:
+
+ http://www.loongson.cn/
+
+Developer web site of Loongson and LoongArch (Software and Documentation):
+
+ http://www.loongnix.cn/
+
+ https://github.com/loongson/
+
+ https://loongson.github.io/LoongArch-Documentation/
+
+Documentation of LoongArch ISA:
+
+ https://github.com/loongson/LoongArch-Documentation/releases/latest/download/LoongArch-Vol1-v1.00-CN.pdf (in Chinese)
+
+ https://github.com/loongson/LoongArch-Documentation/releases/latest/download/LoongArch-Vol1-v1.00-EN.pdf (in English)
+
+Documentation of LoongArch ELF psABI:
+
+ https://github.com/loongson/LoongArch-Documentation/releases/latest/download/LoongArch-ELF-ABI-v1.00-CN.pdf (in Chinese)
+
+ https://github.com/loongson/LoongArch-Documentation/releases/latest/download/LoongArch-ELF-ABI-v1.00-EN.pdf (in English)
+
+Linux kernel repository of Loongson and LoongArch:
+
+ https://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson.git
diff --git a/Documentation/loongarch/irq-chip-model.rst b/Documentation/loongarch/irq-chip-model.rst
new file mode 100644
index 000000000000..8d88f7ab2e5e
--- /dev/null
+++ b/Documentation/loongarch/irq-chip-model.rst
@@ -0,0 +1,156 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+=======================================
+IRQ chip model (hierarchy) of LoongArch
+=======================================
+
+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 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, 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, 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 |
+ +---------+
+
+ACPI-related definitions
+========================
+
+CPUINTC::
+
+ ACPI_MADT_TYPE_CORE_PIC;
+ struct acpi_madt_core_pic;
+ enum acpi_madt_core_pic_version;
+
+LIOINTC::
+
+ ACPI_MADT_TYPE_LIO_PIC;
+ struct acpi_madt_lio_pic;
+ enum acpi_madt_lio_pic_version;
+
+EIOINTC::
+
+ ACPI_MADT_TYPE_EIO_PIC;
+ struct acpi_madt_eio_pic;
+ enum acpi_madt_eio_pic_version;
+
+HTVECINTC::
+
+ ACPI_MADT_TYPE_HT_PIC;
+ struct acpi_madt_ht_pic;
+ enum acpi_madt_ht_pic_version;
+
+PCH-PIC::
+
+ ACPI_MADT_TYPE_BIO_PIC;
+ struct acpi_madt_bio_pic;
+ enum acpi_madt_bio_pic_version;
+
+PCH-MSI::
+
+ ACPI_MADT_TYPE_MSI_PIC;
+ struct acpi_madt_msi_pic;
+ enum acpi_madt_msi_pic_version;
+
+PCH-LPC::
+
+ ACPI_MADT_TYPE_LPC_PIC;
+ struct acpi_madt_lpc_pic;
+ enum acpi_madt_lpc_pic_version;
+
+References
+==========
+
+Documentation of Loongson-3A5000:
+
+ https://github.com/loongson/LoongArch-Documentation/releases/latest/download/Loongson-3A5000-usermanual-1.02-CN.pdf (in Chinese)
+
+ https://github.com/loongson/LoongArch-Documentation/releases/latest/download/Loongson-3A5000-usermanual-1.02-EN.pdf (in English)
+
+Documentation of Loongson's LS7A chipset:
+
+ https://github.com/loongson/LoongArch-Documentation/releases/latest/download/Loongson-7A1000-usermanual-2.00-CN.pdf (in Chinese)
+
+ https://github.com/loongson/LoongArch-Documentation/releases/latest/download/Loongson-7A1000-usermanual-2.00-EN.pdf (in English)
+
+Note: CPUINTC is CSR.ECFG/CSR.ESTAT and its interrupt controller described
+in Section 7.4 of "LoongArch Reference Manual, Vol 1"; LIOINTC is "Legacy I/O
+Interrupts" described in Section 11.1 of "Loongson 3A5000 Processor Reference
+Manual"; EIOINTC is "Extended I/O Interrupts" described in Section 11.2 of
+"Loongson 3A5000 Processor Reference Manual"; HTVECINTC is "HyperTransport
+Interrupts" described in Section 14.3 of "Loongson 3A5000 Processor Reference
+Manual"; PCH-PIC/PCH-MSI is "Interrupt Controller" described in Section 5 of
+"Loongson 7A1000 Bridge User Manual"; PCH-LPC is "LPC Interrupts" described in
+Section 24.3 of "Loongson 7A1000 Bridge User Manual".
diff --git a/Documentation/translations/zh_CN/index.rst b/Documentation/translations/zh_CN/index.rst
index ac32d8e306ac..ad7bb8c17562 100644
--- a/Documentation/translations/zh_CN/index.rst
+++ b/Documentation/translations/zh_CN/index.rst
@@ -171,6 +171,7 @@ TODOList:
riscv/index
openrisc/index
parisc/index
+ loongarch/index
TODOList:
diff --git a/Documentation/translations/zh_CN/loongarch/features.rst b/Documentation/translations/zh_CN/loongarch/features.rst
new file mode 100644
index 000000000000..3886e635ec06
--- /dev/null
+++ b/Documentation/translations/zh_CN/loongarch/features.rst
@@ -0,0 +1,8 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+.. include:: ../disclaimer-zh_CN.rst
+
+:Original: Documentation/loongarch/features.rst
+:Translator: Huacai Chen <chenhuacai@loongson.cn>
+
+.. kernel-feat:: $srctree/Documentation/features loongarch
diff --git a/Documentation/translations/zh_CN/loongarch/index.rst b/Documentation/translations/zh_CN/loongarch/index.rst
new file mode 100644
index 000000000000..7d23eb78379d
--- /dev/null
+++ b/Documentation/translations/zh_CN/loongarch/index.rst
@@ -0,0 +1,26 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+.. include:: ../disclaimer-zh_CN.rst
+
+:Original: Documentation/loongarch/index.rst
+:Translator: Huacai Chen <chenhuacai@loongson.cn>
+
+=================
+LoongArch体系结构
+=================
+
+.. toctree::
+ :maxdepth: 2
+ :numbered:
+
+ introduction
+ irq-chip-model
+
+ features
+
+.. only:: subproject and html
+
+ Indices
+ =======
+
+ * :ref:`genindex`
diff --git a/Documentation/translations/zh_CN/loongarch/introduction.rst b/Documentation/translations/zh_CN/loongarch/introduction.rst
new file mode 100644
index 000000000000..e31a1a928c48
--- /dev/null
+++ b/Documentation/translations/zh_CN/loongarch/introduction.rst
@@ -0,0 +1,351 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+.. include:: ../disclaimer-zh_CN.rst
+
+:Original: Documentation/loongarch/introduction.rst
+:Translator: Huacai Chen <chenhuacai@loongson.cn>
+
+=============
+LoongArch介绍
+=============
+
+LoongArch是一种新的RISC ISA,在一定程度上类似于MIPS和RISC-V。LoongArch指令集
+包括一个精简32位版(LA32R)、一个标准32位版(LA32S)、一个64位版(LA64)。
+LoongArch定义了四个特权级(PLV0~PLV3),其中PLV0是最高特权级,用于内核;而PLV3
+是最低特权级,用于应用程序。本文档介绍了LoongArch的寄存器、基础指令集、虚拟内
+存以及其他一些主题。
+
+寄存器
+======
+
+LoongArch的寄存器包括通用寄存器(GPRs)、浮点寄存器(FPRs)、向量寄存器(VRs)
+和用于特权模式(PLV0)的控制状态寄存器(CSRs)。
+
+通用寄存器
+----------
+
+LoongArch包括32个通用寄存器( ``$r0`` ~ ``$r31`` ),LA32中每个寄存器为32位宽,
+LA64中每个寄存器为64位宽。 ``$r0`` 的内容总是固定为0,而其他寄存器在体系结构层面
+没有特殊功能。( ``$r1`` 算是一个例外,在BL指令中固定用作链接返回寄存器。)
+
+内核使用了一套LoongArch寄存器约定,定义在LoongArch ELF psABI规范中,详细描述参见
+:ref:`参考文献 <loongarch-references-zh_CN>`:
+
+================= =============== =================== ==========
+寄存器名 别名 用途 跨调用保持
+================= =============== =================== ==========
+``$r0`` ``$zero`` 常量0 不使用
+``$r1`` ``$ra`` 返回地址 否
+``$r2`` ``$tp`` TLS/线程信息指针 不使用
+``$r3`` ``$sp`` 栈指针 是
+``$r4``-``$r11`` ``$a0``-``$a7`` 参数寄存器 否
+``$r4``-``$r5`` ``$v0``-``$v1`` 返回值 否
+``$r12``-``$r20`` ``$t0``-``$t8`` 临时寄存器 否
+``$r21`` ``$u0`` 每CPU变量基地址 不使用
+``$r22`` ``$fp`` 帧指针 是
+``$r23``-``$r31`` ``$s0``-``$s8`` 静态寄存器 是
+================= =============== =================== ==========
+
+注意:``$r21``寄存器在ELF psABI中保留未使用,但是在Linux内核用于保存每CPU
+变量基地址。该寄存器没有ABI命名,不过在内核中称为``$u0``。在一些遗留代码
+中有时可能见到``$v0``和``$v1``,它们是``$a0``和``$a1``的别名,属于已经废弃
+的用法。
+
+浮点寄存器
+----------
+
+当系统中存在FPU时,LoongArch有32个浮点寄存器( ``$f0`` ~ ``$f31`` )。在LA64
+的CPU核上,每个寄存器均为64位宽。
+
+浮点寄存器的使用约定与LoongArch ELF psABI规范的描述相同:
+
+================= ================== =================== ==========
+寄存器名 别名 用途 跨调用保持
+================= ================== =================== ==========
+``$f0``-``$f7`` ``$fa0``-``$fa7`` 参数寄存器 否
+``$f0``-``$f1`` ``$fv0``-``$fv1`` 返回值 否
+``$f8``-``$f23`` ``$ft0``-``$ft15`` 临时寄存器 否
+``$f24``-``$f31`` ``$fs0``-``$fs7`` 静态寄存器 是
+================= ================== =================== ==========
+
+注意:在一些遗留代码中有时可能见到 ``$v0`` 和 ``$v1`` ,它们是 ``$a0``
+和 ``$a1`` 的别名,属于已经废弃的用法。
+
+
+向量寄存器
+----------
+
+LoongArch现有两种向量扩展:
+
+- 128位向量扩展LSX(全称Loongson SIMD eXtention),
+- 256位向量扩展LASX(全称Loongson Advanced SIMD eXtention)。
+
+LSX使用 ``$v0`` ~ ``$v31`` 向量寄存器,而LASX则使用 ``$x0`` ~ ``$x31`` 。
+
+浮点寄存器和向量寄存器是复用的,比如:在一个实现了LSX和LASX的核上, ``$x0`` 的
+低128位与 ``$v0`` 共用, ``$v0`` 的低64位与 ``$f0`` 共用,其他寄存器依此类推。
+
+控制状态寄存器
+--------------
+
+控制状态寄存器只能在特权模式(PLV0)下访问:
+
+================= ==================================== ==========
+地址 全称描述 简称
+================= ==================================== ==========
+0x0 当前模式信息 CRMD
+0x1 异常前模式信息 PRMD
+0x2 扩展部件使能 EUEN
+0x3 杂项控制 MISC
+0x4 异常配置 ECFG
+0x5 异常状态 ESTAT
+0x6 异常返回地址 ERA
+0x7 出错(Faulting)虚拟地址 BADV
+0x8 出错(Faulting)指令字 BADI
+0xC 异常入口地址 EENTRY
+0x10 TLB索引 TLBIDX
+0x11 TLB表项高位 TLBEHI
+0x12 TLB表项低位0 TLBELO0
+0x13 TLB表项低位1 TLBELO1
+0x18 地址空间标识符 ASID
+0x19 低半地址空间页全局目录基址 PGDL
+0x1A 高半地址空间页全局目录基址 PGDH
+0x1B 页全局目录基址 PGD
+0x1C 页表遍历控制低半部分 PWCL
+0x1D 页表遍历控制高半部分 PWCH
+0x1E STLB页大小 STLBPS
+0x1F 缩减虚地址配置 RVACFG
+0x20 CPU编号 CPUID
+0x21 特权资源配置信息1 PRCFG1
+0x22 特权资源配置信息2 PRCFG2
+0x23 特权资源配置信息3 PRCFG3
+0x30+n (0≤n≤15) 数据保存寄存器 SAVEn
+0x40 定时器编号 TID
+0x41 定时器配置 TCFG
+0x42 定时器值 TVAL
+0x43 计时器补偿 CNTC
+0x44 定时器中断清除 TICLR
+0x60 LLBit相关控制 LLBCTL
+0x80 实现相关控制1 IMPCTL1
+0x81 实现相关控制2 IMPCTL2
+0x88 TLB重填异常入口地址 TLBRENTRY
+0x89 TLB重填异常出错(Faulting)虚地址 TLBRBADV
+0x8A TLB重填异常返回地址 TLBRERA
+0x8B TLB重填异常数据保存 TLBRSAVE
+0x8C TLB重填异常表项低位0 TLBRELO0
+0x8D TLB重填异常表项低位1 TLBRELO1
+0x8E TLB重填异常表项高位 TLBEHI
+0x8F TLB重填异常前模式信息 TLBRPRMD
+0x90 机器错误控制 MERRCTL
+0x91 机器错误信息1 MERRINFO1
+0x92 机器错误信息2 MERRINFO2
+0x93 机器错误异常入口地址 MERRENTRY
+0x94 机器错误异常返回地址 MERRERA
+0x95 机器错误异常数据保存 MERRSAVE
+0x98 高速缓存标签 CTAG
+0x180+n (0≤n≤3) 直接映射配置窗口n DMWn
+0x200+2n (0≤n≤31) 性能监测配置n PMCFGn
+0x201+2n (0≤n≤31) 性能监测计数器n PMCNTn
+0x300 内存读写监视点整体控制 MWPC
+0x301 内存读写监视点整体状态 MWPS
+0x310+8n (0≤n≤7) 内存读写监视点n配置1 MWPnCFG1
+0x311+8n (0≤n≤7) 内存读写监视点n配置2 MWPnCFG2
+0x312+8n (0≤n≤7) 内存读写监视点n配置3 MWPnCFG3
+0x313+8n (0≤n≤7) 内存读写监视点n配置4 MWPnCFG4
+0x380 取指监视点整体控制 FWPC
+0x381 取指监视点整体状态 FWPS
+0x390+8n (0≤n≤7) 取指监视点n配置1 FWPnCFG1
+0x391+8n (0≤n≤7) 取指监视点n配置2 FWPnCFG2
+0x392+8n (0≤n≤7) 取指监视点n配置3 FWPnCFG3
+0x393+8n (0≤n≤7) 取指监视点n配置4 FWPnCFG4
+0x500 调试寄存器 DBG
+0x501 调试异常返回地址 DERA
+0x502 调试数据保存 DSAVE
+================= ==================================== ==========
+
+ERA,TLBRERA,MERRERA和DERA有时也分别称为EPC,TLBREPC,MERREPC和DEPC。
+
+基础指令集
+==========
+
+指令格式
+--------
+
+LoongArch的指令字长为32位,一共有9种基本指令格式(以及一些变体):
+
+=========== ==========================
+格式名称 指令构成
+=========== ==========================
+2R Opcode + Rj + Rd
+3R Opcode + Rk + Rj + Rd
+4R Opcode + Ra + Rk + Rj + Rd
+2RI8 Opcode + I8 + Rj + Rd
+2RI12 Opcode + I12 + Rj + Rd
+2RI14 Opcode + I14 + Rj + Rd
+2RI16 Opcode + I16 + Rj + Rd
+1RI21 Opcode + I21L + Rj + I21H
+I26 Opcode + I26L + I26H
+=========== ==========================
+
+Opcode是指令操作码,Rj和Rk是源操作数(寄存器),Rd是目标操作数(寄存器),Ra是
+4R-type格式特有的附加操作数(寄存器)。I8/I12/I16/I21/I26分别是8位/12位/16位/
+21位/26位的立即数。其中较长的21位和26位立即数在指令字中被分割为高位部分与低位
+部分,所以你们在这里的格式描述中能够看到I21L/I21H和I26L/I26H这样带后缀的表述。
+
+指令列表
+--------
+
+为了简便起见,我们在此只罗列一下指令名称(助记符),需要详细信息请阅读
+:ref:`参考文献 <loongarch-references-zh_CN>` 中的文档。
+
+1. 算术运算指令::
+
+ ADD.W SUB.W ADDI.W ADD.D SUB.D ADDI.D
+ SLT SLTU SLTI SLTUI
+ AND OR NOR XOR ANDN ORN ANDI ORI XORI
+ MUL.W MULH.W MULH.WU DIV.W DIV.WU MOD.W MOD.WU
+ MUL.D MULH.D MULH.DU DIV.D DIV.DU MOD.D MOD.DU
+ PCADDI PCADDU12I PCADDU18I
+ LU12I.W LU32I.D LU52I.D ADDU16I.D
+
+2. 移位运算指令::
+
+ SLL.W SRL.W SRA.W ROTR.W SLLI.W SRLI.W SRAI.W ROTRI.W
+ SLL.D SRL.D SRA.D ROTR.D SLLI.D SRLI.D SRAI.D ROTRI.D
+
+3. 位域操作指令::
+
+ EXT.W.B EXT.W.H CLO.W CLO.D SLZ.W CLZ.D CTO.W CTO.D CTZ.W CTZ.D
+ BYTEPICK.W BYTEPICK.D BSTRINS.W BSTRINS.D BSTRPICK.W BSTRPICK.D
+ REVB.2H REVB.4H REVB.2W REVB.D REVH.2W REVH.D BITREV.4B BITREV.8B BITREV.W BITREV.D
+ MASKEQZ MASKNEZ
+
+4. 分支转移指令::
+
+ BEQ BNE BLT BGE BLTU BGEU BEQZ BNEZ B BL JIRL
+
+5. 访存读写指令::
+
+ LD.B LD.BU LD.H LD.HU LD.W LD.WU LD.D ST.B ST.H ST.W ST.D
+ LDX.B LDX.BU LDX.H LDX.HU LDX.W LDX.WU LDX.D STX.B STX.H STX.W STX.D
+ LDPTR.W LDPTR.D STPTR.W STPTR.D
+ PRELD PRELDX
+
+6. 原子操作指令::
+
+ LL.W SC.W LL.D SC.D
+ AMSWAP.W AMSWAP.D AMADD.W AMADD.D AMAND.W AMAND.D AMOR.W AMOR.D AMXOR.W AMXOR.D
+ AMMAX.W AMMAX.D AMMIN.W AMMIN.D
+
+7. 栅障指令::
+
+ IBAR DBAR
+
+8. 特殊指令::
+
+ SYSCALL BREAK CPUCFG NOP IDLE ERTN(ERET) DBCL(DBGCALL) RDTIMEL.W RDTIMEH.W RDTIME.D
+ ASRTLE.D ASRTGT.D
+
+9. 特权指令::
+
+ CSRRD CSRWR CSRXCHG
+ IOCSRRD.B IOCSRRD.H IOCSRRD.W IOCSRRD.D IOCSRWR.B IOCSRWR.H IOCSRWR.W IOCSRWR.D
+ CACOP TLBP(TLBSRCH) TLBRD TLBWR TLBFILL TLBCLR TLBFLUSH INVTLB LDDIR LDPTE
+
+虚拟内存
+========
+
+LoongArch可以使用直接映射虚拟内存和分页映射虚拟内存。
+
+直接映射虚拟内存通过CSR.DMWn(n=0~3)来进行配置,虚拟地址(VA)和物理地址(PA)
+之间有简单的映射关系::
+
+ VA = PA + 固定偏移
+
+分页映射的虚拟地址(VA)和物理地址(PA)有任意的映射关系,这种关系记录在TLB和页
+表中。LoongArch的TLB包括一个全相联的MTLB(Multiple Page Size TLB,多样页大小TLB)
+和一个组相联的STLB(Single Page Size TLB,单一页大小TLB)。
+
+缺省状态下,LA32的整个虚拟地址空间配置如下:
+
+============ =========================== ===========================
+区段名 地址范围 属性
+============ =========================== ===========================
+``UVRANGE`` ``0x00000000 - 0x7FFFFFFF`` 分页映射, 可缓存, PLV0~3
+``KPRANGE0`` ``0x80000000 - 0x9FFFFFFF`` 直接映射, 非缓存, PLV0
+``KPRANGE1`` ``0xA0000000 - 0xBFFFFFFF`` 直接映射, 可缓存, PLV0
+``KVRANGE`` ``0xC0000000 - 0xFFFFFFFF`` 分页映射, 可缓存, PLV0
+============ =========================== ===========================
+
+用户态(PLV3)只能访问UVRANGE,对于直接映射的KPRANGE0和KPRANGE1,将虚拟地址的第
+30~31位清零就等于物理地址。例如:物理地址0x00001000对应的非缓存直接映射虚拟地址
+是0x80001000,而其可缓存直接映射虚拟地址是0xA0001000。
+
+缺省状态下,LA64的整个虚拟地址空间配置如下:
+
+============ ====================== ==================================
+区段名 地址范围 属性
+============ ====================== ==================================
+``XUVRANGE`` ``0x0000000000000000 - 分页映射, 可缓存, PLV0~3
+ 0x3FFFFFFFFFFFFFFF``
+``XSPRANGE`` ``0x4000000000000000 - 直接映射, 可缓存 / 非缓存, PLV0
+ 0x7FFFFFFFFFFFFFFF``
+``XKPRANGE`` ``0x8000000000000000 - 直接映射, 可缓存 / 非缓存, PLV0
+ 0xBFFFFFFFFFFFFFFF``
+``XKVRANGE`` ``0xC000000000000000 - 分页映射, 可缓存, PLV0
+ 0xFFFFFFFFFFFFFFFF``
+============ ====================== ==================================
+
+用户态(PLV3)只能访问XUVRANGE,对于直接映射的XSPRANGE和XKPRANGE,将虚拟地址的第
+60~63位清零就等于物理地址,而其缓存属性是通过虚拟地址的第60~61位配置的(0表示强序
+非缓存,1表示一致可缓存,2表示弱序非缓存)。
+
+目前,我们仅用XKPRANGE来进行直接映射,XSPRANGE保留给以后用。
+
+此处给出一个直接映射的例子:物理地址0x00000000_00001000的强序非缓存直接映射虚拟地址
+(在XKPRANGE中)是0x80000000_00001000,其一致可缓存直接映射虚拟地址(在XKPRANGE中)
+是0x90000000_00001000,而其弱序非缓存直接映射虚拟地址(在XKPRANGE中)是0xA0000000_
+00001000。
+
+Loongson与LoongArch的关系
+=========================
+
+LoongArch是一种RISC指令集架构(ISA),不同于现存的任何一种ISA,而Loongson(即龙
+芯)是一个处理器家族。龙芯包括三个系列:Loongson-1(龙芯1号)是32位处理器系列,
+Loongson-2(龙芯2号)是低端64位处理器系列,而Loongson-3(龙芯3号)是高端64位处理
+器系列。旧的龙芯处理器基于MIPS架构,而新的龙芯处理器基于LoongArch架构。以龙芯3号
+为例:龙芯3A1000/3B1500/3A2000/3A3000/3A4000都是兼容MIPS的,而龙芯3A5000(以及将
+来的型号)都是基于LoongArch的。
+
+.. _loongarch-references-zh_CN:
+
+参考文献
+========
+
+Loongson官方网站(龙芯中科技术股份有限公司):
+
+ http://www.loongson.cn/
+
+Loongson与LoongArch的开发者网站(软件与文档资源):
+
+ http://www.loongnix.cn/
+
+ https://github.com/loongson/
+
+ https://loongson.github.io/LoongArch-Documentation/
+
+LoongArch指令集架构的文档:
+
+ https://github.com/loongson/LoongArch-Documentation/releases/latest/download/LoongArch-Vol1-v1.00-CN.pdf (中文版)
+
+ https://github.com/loongson/LoongArch-Documentation/releases/latest/download/LoongArch-Vol1-v1.00-EN.pdf (英文版)
+
+LoongArch的ELF psABI文档:
+
+ https://github.com/loongson/LoongArch-Documentation/releases/latest/download/LoongArch-ELF-ABI-v1.00-CN.pdf (中文版)
+
+ https://github.com/loongson/LoongArch-Documentation/releases/latest/download/LoongArch-ELF-ABI-v1.00-EN.pdf (英文版)
+
+Loongson与LoongArch的Linux内核源码仓库:
+
+ https://git.kernel.org/pub/scm/linux/kernel/git/chenhuacai/linux-loongson.git
diff --git a/Documentation/translations/zh_CN/loongarch/irq-chip-model.rst b/Documentation/translations/zh_CN/loongarch/irq-chip-model.rst
new file mode 100644
index 000000000000..2a4c3ad38be4
--- /dev/null
+++ b/Documentation/translations/zh_CN/loongarch/irq-chip-model.rst
@@ -0,0 +1,155 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+.. include:: ../disclaimer-zh_CN.rst
+
+:Original: Documentation/loongarch/irq-chip-model.rst
+:Translator: Huacai Chen <chenhuacai@loongson.cn>
+
+==================================
+LoongArch的IRQ芯片模型(层级关系)
+==================================
+
+目前,基于LoongArch的处理器(如龙芯3A5000)只能与LS7A芯片组配合工作。LoongArch计算机
+中的中断控制器(即IRQ芯片)包括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(LS7A芯片组的主中
+断控制器)、PCH-LPC(LS7A芯片组的LPC中断控制器)和PCH-MSI(MSI中断控制器)。
+
+CPUINTC是一种CPU内部的每个核本地的中断控制器,LIOINTC/EIOINTC/HTVECINTC是CPU内部的
+全局中断控制器(每个芯片一个,所有核共享),而PCH-PIC/PCH-LPC/PCH-MSI是CPU外部的中
+断控制器(在配套芯片组里面)。这些中断控制器(或者说IRQ芯片)以一种层次树的组织形式
+级联在一起,一共有两种层级关系模型(传统IRQ模型和扩展IRQ模型)。
+
+传统IRQ模型
+===========
+
+在这种模型里面,IPI(Inter-Processor Interrupt)和CPU本地时钟中断直接发送到CPUINTC,
+CPU串口(UARTs)中断发送到LIOINTC,而其他所有设备的中断则分别发送到所连接的PCH-PIC/
+PCH-LPC/PCH-MSI,然后被HTVECINTC统一收集,再发送到LIOINTC,最后到达CPUINTC::
+
+ +-----+ +---------+ +-------+
+ | IPI | --> | CPUINTC | <-- | Timer |
+ +-----+ +---------+ +-------+
+ ^
+ |
+ +---------+ +-------+
+ | LIOINTC | <-- | UARTs |
+ +---------+ +-------+
+ ^
+ |
+ +-----------+
+ | HTVECINTC |
+ +-----------+
+ ^ ^
+ | |
+ +---------+ +---------+
+ | PCH-PIC | | PCH-MSI |
+ +---------+ +---------+
+ ^ ^ ^
+ | | |
+ +---------+ +---------+ +---------+
+ | PCH-LPC | | Devices | | Devices |
+ +---------+ +---------+ +---------+
+ ^
+ |
+ +---------+
+ | Devices |
+ +---------+
+
+扩展IRQ模型
+===========
+
+在这种模型里面,IPI(Inter-Processor Interrupt)和CPU本地时钟中断直接发送到CPUINTC,
+CPU串口(UARTs)中断发送到LIOINTC,而其他所有设备的中断则分别发送到所连接的PCH-PIC/
+PCH-LPC/PCH-MSI,然后被EIOINTC统一收集,再直接到达CPUINTC::
+
+ +-----+ +---------+ +-------+
+ | IPI | --> | CPUINTC | <-- | Timer |
+ +-----+ +---------+ +-------+
+ ^ ^
+ | |
+ +---------+ +---------+ +-------+
+ | EIOINTC | | LIOINTC | <-- | UARTs |
+ +---------+ +---------+ +-------+
+ ^ ^
+ | |
+ +---------+ +---------+
+ | PCH-PIC | | PCH-MSI |
+ +---------+ +---------+
+ ^ ^ ^
+ | | |
+ +---------+ +---------+ +---------+
+ | PCH-LPC | | Devices | | Devices |
+ +---------+ +---------+ +---------+
+ ^
+ |
+ +---------+
+ | Devices |
+ +---------+
+
+ACPI相关的定义
+==============
+
+CPUINTC::
+
+ ACPI_MADT_TYPE_CORE_PIC;
+ struct acpi_madt_core_pic;
+ enum acpi_madt_core_pic_version;
+
+LIOINTC::
+
+ ACPI_MADT_TYPE_LIO_PIC;
+ struct acpi_madt_lio_pic;
+ enum acpi_madt_lio_pic_version;
+
+EIOINTC::
+
+ ACPI_MADT_TYPE_EIO_PIC;
+ struct acpi_madt_eio_pic;
+ enum acpi_madt_eio_pic_version;
+
+HTVECINTC::
+
+ ACPI_MADT_TYPE_HT_PIC;
+ struct acpi_madt_ht_pic;
+ enum acpi_madt_ht_pic_version;
+
+PCH-PIC::
+
+ ACPI_MADT_TYPE_BIO_PIC;
+ struct acpi_madt_bio_pic;
+ enum acpi_madt_bio_pic_version;
+
+PCH-MSI::
+
+ ACPI_MADT_TYPE_MSI_PIC;
+ struct acpi_madt_msi_pic;
+ enum acpi_madt_msi_pic_version;
+
+PCH-LPC::
+
+ ACPI_MADT_TYPE_LPC_PIC;
+ struct acpi_madt_lpc_pic;
+ enum acpi_madt_lpc_pic_version;
+
+参考文献
+========
+
+龙芯3A5000的文档:
+
+ https://github.com/loongson/LoongArch-Documentation/releases/latest/download/Loongson-3A5000-usermanual-1.02-CN.pdf (中文版)
+
+ https://github.com/loongson/LoongArch-Documentation/releases/latest/download/Loongson-3A5000-usermanual-1.02-EN.pdf (英文版)
+
+龙芯LS7A芯片组的文档:
+
+ https://github.com/loongson/LoongArch-Documentation/releases/latest/download/Loongson-7A1000-usermanual-2.00-CN.pdf (中文版)
+
+ https://github.com/loongson/LoongArch-Documentation/releases/latest/download/Loongson-7A1000-usermanual-2.00-EN.pdf (英文版)
+
+注:CPUINTC即《龙芯架构参考手册卷一》第7.4节所描述的CSR.ECFG/CSR.ESTAT寄存器及其中断
+控制逻辑;LIOINTC即《龙芯3A5000处理器使用手册》第11.1节所描述的“传统I/O中断”;EIOINTC
+即《龙芯3A5000处理器使用手册》第11.2节所描述的“扩展I/O中断”;HTVECINTC即《龙芯3A5000
+处理器使用手册》第14.3节所描述的“HyperTransport中断”;PCH-PIC/PCH-MSI即《龙芯7A1000桥
+片用户手册》第5章所描述的“中断控制器”;PCH-LPC即《龙芯7A1000桥片用户手册》第24.3节所
+描述的“LPC中断”。