summaryrefslogtreecommitdiffstats
path: root/arch/nds32/Kconfig.cpu
diff options
context:
space:
mode:
authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
commit5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 (patch)
treea94efe259b9009378be6d90eb30d2b019d95c194 /arch/nds32/Kconfig.cpu
parentInitial commit. (diff)
downloadlinux-5d1646d90e1f2cceb9f0828f4b28318cd0ec7744.tar.xz
linux-5d1646d90e1f2cceb9f0828f4b28318cd0ec7744.zip
Adding upstream version 5.10.209.upstream/5.10.209
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/nds32/Kconfig.cpu')
-rw-r--r--arch/nds32/Kconfig.cpu217
1 files changed, 217 insertions, 0 deletions
diff --git a/arch/nds32/Kconfig.cpu b/arch/nds32/Kconfig.cpu
new file mode 100644
index 000000000..f88a12fdf
--- /dev/null
+++ b/arch/nds32/Kconfig.cpu
@@ -0,0 +1,217 @@
+# SPDX-License-Identifier: GPL-2.0-only
+comment "Processor Features"
+
+config CPU_BIG_ENDIAN
+ def_bool !CPU_LITTLE_ENDIAN
+
+config CPU_LITTLE_ENDIAN
+ bool "Little endian"
+ default y
+
+config FPU
+ bool "FPU support"
+ default n
+ help
+ If FPU ISA is used in user space, this configuration shall be Y to
+ enable required support in kernel such as fpu context switch and
+ fpu exception handler.
+
+ If no FPU ISA is used in user space, say N.
+
+config LAZY_FPU
+ bool "lazy FPU support"
+ depends on FPU
+ default y
+ help
+ Say Y here to enable the lazy FPU scheme. The lazy FPU scheme can
+ enhance system performance by reducing the context switch
+ frequency of the FPU register.
+
+ For normal case, say Y.
+
+config SUPPORT_DENORMAL_ARITHMETIC
+ bool "Denormal arithmetic support"
+ depends on FPU
+ default n
+ help
+ Say Y here to enable arithmetic of denormalized number. Enabling
+ this feature can enhance the precision for tininess number.
+ However, performance loss in float point calculations is
+ possibly significant due to additional FPU exception.
+
+ If the calculated tolerance for tininess number is not critical,
+ say N to prevent performance loss.
+
+config HWZOL
+ bool "hardware zero overhead loop support"
+ depends on CPU_D10 || CPU_D15
+ default n
+ help
+ A set of Zero-Overhead Loop mechanism is provided to reduce the
+ instruction fetch and execution overhead of loop-control instructions.
+ It will save 3 registers($LB, $LC, $LE) for context saving if say Y.
+ You don't need to save these registers if you can make sure your user
+ program doesn't use these registers.
+
+ If unsure, say N.
+
+config CPU_CACHE_ALIASING
+ bool "Aliasing cache"
+ depends on CPU_N10 || CPU_D10 || CPU_N13 || CPU_V3
+ default y
+ help
+ If this CPU is using VIPT data cache and its cache way size is larger
+ than page size, say Y. If it is using PIPT data cache, say N.
+
+ If unsure, say Y.
+
+choice
+ prompt "minimum CPU type"
+ default CPU_V3
+ help
+ The data cache of N15/D15 is implemented as PIPT and it will not cause
+ the cache aliasing issue. The rest cpus(N13, N10 and D10) are
+ implemented as VIPT data cache. It may cause the cache aliasing issue
+ if its cache way size is larger than page size. You can specify the
+ CPU type directly or choose CPU_V3 if unsure.
+
+ A kernel built for N10 is able to run on N15, D15, N13, N10 or D10.
+ A kernel built for N15 is able to run on N15 or D15.
+ A kernel built for D10 is able to run on D10 or D15.
+ A kernel built for D15 is able to run on D15.
+ A kernel built for N13 is able to run on N15, N13 or D15.
+
+config CPU_N15
+ bool "AndesCore N15"
+config CPU_N13
+ bool "AndesCore N13"
+ select CPU_CACHE_ALIASING if ANDES_PAGE_SIZE_4KB
+config CPU_N10
+ bool "AndesCore N10"
+ select CPU_CACHE_ALIASING
+config CPU_D15
+ bool "AndesCore D15"
+config CPU_D10
+ bool "AndesCore D10"
+ select CPU_CACHE_ALIASING
+config CPU_V3
+ bool "AndesCore v3 compatible"
+ select CPU_CACHE_ALIASING
+endchoice
+choice
+ prompt "Paging -- page size "
+ default ANDES_PAGE_SIZE_4KB
+config ANDES_PAGE_SIZE_4KB
+ bool "use 4KB page size"
+config ANDES_PAGE_SIZE_8KB
+ bool "use 8KB page size"
+endchoice
+
+config CPU_ICACHE_DISABLE
+ bool "Disable I-Cache"
+ help
+ Say Y here to disable the processor instruction cache. Unless
+ you have a reason not to or are unsure, say N.
+
+config CPU_DCACHE_DISABLE
+ bool "Disable D-Cache"
+ help
+ Say Y here to disable the processor data cache. Unless
+ you have a reason not to or are unsure, say N.
+
+config CPU_DCACHE_WRITETHROUGH
+ bool "Force write through D-cache"
+ depends on !CPU_DCACHE_DISABLE
+ help
+ Say Y here to use the data cache in writethrough mode. Unless you
+ specifically require this or are unsure, say N.
+
+config WBNA
+ bool "WBNA"
+ default n
+ help
+ Say Y here to enable write-back memory with no-write-allocation policy.
+
+config ALIGNMENT_TRAP
+ bool "Kernel support unaligned access handling by sw"
+ depends on PROC_FS
+ default n
+ help
+ Andes processors cannot load/store information which is not
+ naturally aligned on the bus, i.e., a 4 byte load must start at an
+ address divisible by 4. On 32-bit Andes processors, these non-aligned
+ load/store instructions will be emulated in software if you say Y
+ here, which has a severe performance impact. With an IP-only
+ configuration it is safe to say N, otherwise say Y.
+
+config HW_SUPPORT_UNALIGNMENT_ACCESS
+ bool "Kernel support unaligned access handling by hw"
+ depends on !ALIGNMENT_TRAP
+ default n
+ help
+ Andes processors load/store world/half-word instructions can access
+ unaligned memory locations without generating the Data Alignment
+ Check exceptions. With an IP-only configuration it is safe to say N,
+ otherwise say Y.
+
+config HIGHMEM
+ bool "High Memory Support"
+ depends on MMU && !CPU_CACHE_ALIASING
+ help
+ The address space of Andes processors is only 4 Gigabytes large
+ and it has to accommodate user address space, kernel address
+ space as well as some memory mapped IO. That means that, if you
+ have a large amount of physical memory and/or IO, not all of the
+ memory can be "permanently mapped" by the kernel. The physical
+ memory that is not permanently mapped is called "high memory".
+
+ Depending on the selected kernel/user memory split, minimum
+ vmalloc space and actual amount of RAM, you may not need this
+ option which should result in a slightly faster kernel.
+
+ If unsure, say N.
+
+config CACHE_L2
+ bool "Support L2 cache"
+ default y
+ help
+ Say Y here to enable L2 cache if your SoC are integrated with L2CC.
+ If unsure, say N.
+
+config HW_PRE
+ bool "Enable hardware prefetcher"
+ default y
+ help
+ Say Y here to enable hardware prefetcher feature.
+ Only when CPU_VER.REV >= 0x09 can support.
+
+menu "Memory configuration"
+
+choice
+ prompt "Memory split"
+ depends on MMU
+ default VMSPLIT_3G_OPT
+ help
+ Select the desired split between kernel and user memory.
+
+ If you are not absolutely sure what you are doing, leave this
+ option alone!
+
+ config VMSPLIT_3G
+ bool "3G/1G user/kernel split"
+ config VMSPLIT_3G_OPT
+ bool "3G/1G user/kernel split (for full 1G low memory)"
+ config VMSPLIT_2G
+ bool "2G/2G user/kernel split"
+ config VMSPLIT_1G
+ bool "1G/3G user/kernel split"
+endchoice
+
+config PAGE_OFFSET
+ hex
+ default 0x40000000 if VMSPLIT_1G
+ default 0x80000000 if VMSPLIT_2G
+ default 0xB0000000 if VMSPLIT_3G_OPT
+ default 0xC0000000
+
+endmenu