LoongArch: Change acpi_core_pic[NR_CPUS] to acpi_core_pic[MAX_CORE_PIC]

With default config, the value of NR_CPUS is 64. When HW platform has
more then 64 cpus, system will crash on these platforms. MAX_CORE_PIC
is the maximum cpu number in MADT table (max physical number) which can
exceed the supported maximum cpu number (NR_CPUS, max logical number),
but kernel should not crash. Kernel should boot cpus with NR_CPUS, let
the remainder cpus stay in BIOS.

The potential crash reason is that the array acpi_core_pic[NR_CPUS] can
be overflowed when parsing MADT table, and it is obvious that CORE_PIC
should be corresponding to physical core rather than logical core, so it
is better to define the array as acpi_core_pic[MAX_CORE_PIC].

With the patch, system can boot up 64 vcpus with qemu parameter -smp 128,
otherwise system will crash with the following message.

[ 0.000000] CPU 0 Unable to handle kernel paging request at virtual address 0000420000004259, era == 90000000037a5f0c, ra == 90000000037a46ec
[ 0.000000] Oops[#1]:
[ 0.000000] CPU: 0 PID: 0 Comm: swapper Not tainted 6.8.0-rc2+ #192
[ 0.000000] Hardware name: QEMU QEMU Virtual Machine, BIOS unknown 2/2/2022
[ 0.000000] pc 90000000037a5f0c ra 90000000037a46ec tp 9000000003c90000 sp 9000000003c93d60
[ 0.000000] a0 0000000000000019 a1 9000000003d93bc0 a2 0000000000000000 a3 9000000003c93bd8
[ 0.000000] a4 9000000003c93a74 a5 9000000083c93a67 a6 9000000003c938f0 a7 0000000000000005
[ 0.000000] t0 0000420000004201 t1 0000000000000000 t2 0000000000000001 t3 0000000000000001
[ 0.000000] t4 0000000000000003 t5 0000000000000000 t6 0000000000000030 t7 0000000000000063
[ 0.000000] t8 0000000000000014 u0 ffffffffffffffff s9 0000000000000000 s0 9000000003caee98
[ 0.000000] s1 90000000041b0480 s2 9000000003c93da0 s3 9000000003c93d98 s4 9000000003c93d90
[ 0.000000] s5 9000000003caa000 s6 000000000a7fd000 s7 000000000f556b60 s8 000000000e0a4330
[ 0.000000] ra: 90000000037a46ec platform_init+0x214/0x250
[ 0.000000] ERA: 90000000037a5f0c efi_runtime_init+0x30/0x94
[ 0.000000] CRMD: 000000b0 (PLV0 -IE -DA +PG DACF=CC DACM=CC -WE)
[ 0.000000] PRMD: 00000000 (PPLV0 -PIE -PWE)
[ 0.000000] EUEN: 00000000 (-FPE -SXE -ASXE -BTE)
[ 0.000000] ECFG: 00070800 (LIE=11 VS=7)
[ 0.000000] ESTAT: 00010000 [PIL] (IS= ECode=1 EsubCode=0)
[ 0.000000] BADV: 0000420000004259
[ 0.000000] PRID: 0014c010 (Loongson-64bit, Loongson-3A5000)
[ 0.000000] Modules linked in:
[ 0.000000] Process swapper (pid: 0, threadinfo=(____ptrval____), task=(____ptrval____))
[ 0.000000] Stack : 9000000003c93a14 9000000003800898 90000000041844f8 90000000037a46ec
[ 0.000000] 000000000a7fd000 0000000008290000 0000000000000000 0000000000000000
[ 0.000000] 0000000000000000 0000000000000000 00000000019d8000 000000000f556b60
[ 0.000000] 000000000a7fd000 000000000f556b08 9000000003ca7700 9000000003800000
[ 0.000000] 9000000003c93e50 9000000003800898 9000000003800108 90000000037a484c
[ 0.000000] 000000000e0a4330 000000000f556b60 000000000a7fd000 000000000f556b08
[ 0.000000] 9000000003ca7700 9000000004184000 0000000000200000 000000000e02b018
[ 0.000000] 000000000a7fd000 90000000037a0790 9000000003800108 0000000000000000
[ 0.000000] 0000000000000000 000000000e0a4330 000000000f556b60 000000000a7fd000
[ 0.000000] 000000000f556b08 000000000eaae298 000000000eaa5040 0000000000200000
[ 0.000000] ...
[ 0.000000] Call Trace:
[ 0.000000] [<90000000037a5f0c>] efi_runtime_init+0x30/0x94
[ 0.000000] [<90000000037a46ec>] platform_init+0x214/0x250
[ 0.000000] [<90000000037a484c>] setup_arch+0x124/0x45c
[ 0.000000] [<90000000037a0790>] start_kernel+0x90/0x670
[ 0.000000] [<900000000378b0d8>] kernel_entry+0xd8/0xdc

Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

LoongArch: Let cores_io_master cover the largest NR_CPUS

Now loongson_system_configuration::cores_io_master only covers 64 cpus,
if NR_CPUS > 64 there will be memory corruption. So let cores_io_master
cover the largest NR_CPUS (256).

Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

LoongArch: Fix some build warnings with W=1

There are some building warnings when building LoongArch kernel with W=1
as following, this patch fixes them.

arch/loongarch/kernel/acpi.c:284:13: warning: no previous prototype for ‘acpi_numa_arch_fixup’ [-Wmissing-prototypes]
284 | void __init acpi_numa_arch_fixup(void) {}
| ^~~~~~~~~~~~~~~~~~~~
arch/loongarch/kernel/time.c:32:13: warning: no previous prototype for ‘constant_timer_interrupt’ [-Wmissing-prototypes]
32 | irqreturn_t constant_timer_interrupt(int irq, void *data)
| ^~~~~~~~~~~~~~~~~~~~~~~~
arch/loongarch/kernel/traps.c:496:25: warning: no previous prototype for 'do_fpe' [-Wmissing-prototypes]
496 | asmlinkage void noinstr do_fpe(struct pt_regs *regs
| ^~~~~~
arch/loongarch/kernel/traps.c:813:22: warning: variable ‘opcode’ set but not used [-Wunused-but-set-variable]
813 | unsigned int opcode;
| ^~~~~~
arch/loongarch/kernel/signal.c:895:14: warning: no previous prototype for ‘get_sigframe’ [-Wmissing-prototypes]
895 | void __user *get_sigframe(struct ksignal *ksig, struct pt_regs *regs,
| ^~~~~~~~~~~~
arch/loongarch/kernel/syscall.c:21:40: warning: initialized field overwritten [-Woverride-init]
21 | #define __SYSCALL(nr, call) [nr] = (call),
| ^
arch/loongarch/kernel/syscall.c:40:14: warning: no previous prototype for ‘do_syscall’ [-Wmissing-prototypes]
40 | void noinstr do_syscall(struct pt_regs *regs)
| ^~~~~~~~~~
arch/loongarch/kernel/smp.c:502:17: warning: no previous prototype for ‘start_secondary’ [-Wmissing-prototypes]
502 | asmlinkage void start_secondary(void)
| ^~~~~~~~~~~~~~~
arch/loongarch/kernel/process.c:309:15: warning: no previous prototype for ‘arch_align_stack’ [-Wmissing-prototypes]
309 | unsigned long arch_align_stack(unsigned long sp)
| ^~~~~~~~~~~~~~~~
arch/loongarch/kernel/topology.c:13:5: warning: no previous prototype for ‘arch_register_cpu’ [-Wmissing-prototypes]
13 | int arch_register_cpu(int cpu)
| ^~~~~~~~~~~~~~~~~
arch/loongarch/kernel/topology.c:27:6: warning: no previous prototype for ‘arch_unregister_cpu’ [-Wmissing-prototypes]
27 | void arch_unregister_cpu(int cpu)
| ^~~~~~~~~~~~~~~~~~~
arch/loongarch/kernel/module-sections.c:103:5: warning: no previous prototype for ‘module_frob_arch_sections’ [-Wmissing-prototypes]
103 | int module_frob_arch_sections(Elf_Ehdr *ehdr, Elf_Shdr *sechdrs,
| ^~~~~~~~~~~~~~~~~~~~~~~~~
arch/loongarch/mm/hugetlbpage.c:56:5: warning: no previous prototype for ‘is_aligned_hugepage_range’ [-Wmissing-prototypes]
56 | int is_aligned_hugepage_range(unsigned long addr, unsigned long len)
| ^~~~~~~~~~~~~~~~~~~~~~~~~

Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

LoongArch: Add SMT (Simultaneous Multi-Threading) support

Loongson-3A6000 has SMT (Simultaneous Multi-Threading) support, each
physical core has two logical cores (threads). This patch add SMT probe
and scheduler support via ACPI PPTT.

If SCHED_SMT enabled, Loongson-3A6000 is treated as 4 cores, 8 threads;
If SCHED_SMT disabled, Loongson-3A6000 is treated as 8 cores, 8 threads.

Remove smp_num_siblings to support HMP (Heterogeneous Multi-Processing).

Signed-off-by: Liupu Wang <wangliupu@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

LoongArch: Add suspend (ACPI S3) support

Add suspend (Suspend To RAM, aka ACPI S3) support for LoongArch.

Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

LoongArch: Add FDT booting support from efi system table

Since commit 40cd01a9c324("efi/loongarch: libstub: remove dependency on
flattened DT"), we can parse the FDT from efi system table.

And now, LoongArch is coming to support booting with FDT, so we add the
relevant booting support as well as parameter parsing.

Signed-off-by: Binbin Zhou <zhoubinbin@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

LoongArch: Combine acpi_boot_table_init() and acpi_boot_init()

Combine acpi_boot_table_init() and acpi_boot_init() since they are very
simple, and we don't need to check the return value of acpi_boot_init().

Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

LoongArch: Fix section mismatch due to acpi_os_ioremap()

Now acpi_os_ioremap() is marked with __init because it calls memblock_
is_memory() which is also marked with __init in the !ARCH_KEEP_MEMBLOCK
case. However, acpi_os_ioremap() is called by ordinary functions such
as acpi_os_{read, write}_memory() and causes section mismatch warnings:

WARNING: modpost: vmlinux.o: section mismatch in reference: acpi_os_read_memory (section: .text) -> acpi_os_ioremap (section: .init.text)
WARNING: modpost: vmlinux.o: section mismatch in reference: acpi_os_write_memory (section: .text) -> acpi_os_ioremap (section: .init.text)

Fix these warnings by selecting ARCH_KEEP_MEMBLOCK unconditionally and
removing the __init modifier of acpi_os_ioremap(). This can also give a
chance to track "memory" and "reserved" memblocks after early boot.

Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

LoongArch: Parse MADT to get multi-processor information

Parse MADT to get multi-processor information, in order to fix the boot
problem and cpu-hotplug problem for SMP platform.

Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

LoongArch: Use ACPI_GENERIC_GSI for gsi handling

For LoongArch, generic gsi code(driver/acpi/irq.c) can be
reused after following patchs:

APCI: irq: Add support for multiple GSI domains
ACPI: irq: Allow acpi_gsi_to_irq() to have an arch-specific fallback

So, config ACPI_GENERIC_GSI for LoongArch with removing the gsi code
in arch directory.

Signed-off-by: Jianmin Lv <lvjianmin@loongson.cn>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/1658314292-35346-6-git-send-email-lvjianmin@loongson.cn

LoongArch: Fix the !CONFIG_SMP build

1, We assume arch/loongarch/include/asm/smp.h be included in include/
linux/smp.h is valid and the reverse inclusion isn't. So remove the
<linux/smp.h> in arch/loongarch/include/asm/smp.h.
2, arch/loongarch/include/asm/smp.h is only needed when CONFIG_SMP,
and setup.c include it only because it need plat_smp_setup(). So,
reorganize setup.c & smp.h, and then remove <asm/smp.h> in setup.c.
3, Fix cacheinfo.c and percpu.h build error by adding the missing header
files when !CONFIG_SMP.
4, Fix acpi.c build error by adding CONFIG_SMP guards.
5, Move irq_stat definition from smp.c to irq.c and fix its declaration.
6, Select CONFIG_SMP for CONFIG_NUMA, similar as other architectures do.

Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

LoongArch: Add Non-Uniform Memory Access (NUMA) support

Add Non-Uniform Memory Access (NUMA) support for LoongArch. LoongArch
has 48-bit physical address, but the HyperTransport I/O bus only support
40-bit address, so we need a custom phys_to_dma() and dma_to_phys() to
extract the 4-bit node id (bit 44~47) from Loongson-3's 48-bit physical
address space and embed it into 40-bit. In the 40-bit dma address, node
id offset can be read from the LS7A_DMA_CFG register.

Reviewed-by: WANG Xuerui <git@xen0n.name>
Reviewed-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

LoongArch: Add multi-processor (SMP) support

LoongArch-based procesors have 4, 8 or 16 cores per package. This patch
adds multi-processor (SMP) support for LoongArch.

Reviewed-by: WANG Xuerui <git@xen0n.name>
Reviewed-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>

LoongArch: Add boot and setup routines

Add basic boot, setup and reset routines for LoongArch. Now, LoongArch
machines use UEFI-based firmware. The firmware passes configuration
information to the kernel via ACPI and DMI/SMBIOS.

Currently an existing interface between the kernel and the bootloader
is implemented. Kernel gets 2 values from the bootloader, passed in
registers a0 and a1; a0 is an "EFI boot flag" distinguishing UEFI and
non-UEFI firmware, while a1 is a pointer to an FDT with systable,
memmap, cmdline and initrd information.

The standard UEFI boot protocol (EFISTUB) will be added later.

Cc: linux-efi@vger.kernel.org
Cc: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: WANG Xuerui <git@xen0n.name>
Reviewed-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Co-developed-by: Yun Liu <liuyun@loongson.cn>
Signed-off-by: Yun Liu <liuyun@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>