riscv: add nommu support

[tomoyo/tomoyo-test1.git] / arch / riscv / Kconfig

diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
index b85492c..babc8a0 100644 (file)
--- a/arch/riscv/Kconfig
+++ b/arch/riscv/Kconfig
@@ -26,14 +26,14 @@ config RISCV
        select GENERIC_IRQ_SHOW
        select GENERIC_PCI_IOMAP
        select GENERIC_SCHED_CLOCK
-       select GENERIC_STRNCPY_FROM_USER
-       select GENERIC_STRNLEN_USER
+       select GENERIC_STRNCPY_FROM_USER if MMU
+       select GENERIC_STRNLEN_USER if MMU
        select GENERIC_SMP_IDLE_THREAD
        select GENERIC_ATOMIC64 if !64BIT
        select HAVE_ARCH_AUDITSYSCALL
        select HAVE_ASM_MODVERSIONS
        select HAVE_MEMBLOCK_NODE_MAP
-       select HAVE_DMA_CONTIGUOUS
+       select HAVE_DMA_CONTIGUOUS if MMU
        select HAVE_FUTEX_CMPXCHG if FUTEX
        select HAVE_PERF_EVENTS
        select HAVE_PERF_REGS
@@ -50,6 +50,7 @@ config RISCV
        select PCI_DOMAINS_GENERIC if PCI
        select PCI_MSI if PCI
        select RISCV_TIMER
+       select UACCESS_MEMCPY if !MMU
        select GENERIC_IRQ_MULTI_HANDLER
        select GENERIC_ARCH_TOPOLOGY if SMP
        select ARCH_HAS_PTE_SPECIAL
@@ -60,7 +61,7 @@ config RISCV
        select ARCH_WANT_HUGE_PMD_SHARE if 64BIT
        select SPARSEMEM_STATIC if 32BIT
        select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT if MMU
-       select HAVE_ARCH_MMAP_RND_BITS
+       select HAVE_ARCH_MMAP_RND_BITS if MMU
 
 config ARCH_MMAP_RND_BITS_MIN
        default 18 if 64BIT
@@ -75,6 +76,7 @@ config ARCH_MMAP_RND_BITS_MAX
 # set if we run in machine mode, cleared if we run in supervisor mode
 config RISCV_M_MODE
        bool
+       default !MMU
 
 # set if we are running in S-mode and can use SBI calls
 config RISCV_SBI
@@ -83,7 +85,11 @@ config RISCV_SBI
        default y
 
 config MMU
-       def_bool y
+       bool "MMU-based Paged Memory Management Support"
+       default y
+       help
+         Select if you want MMU-based virtualised addressing space
+         support by paged memory management. If unsure, say 'Y'.
 
 config ZONE_DMA32
        bool
@@ -102,6 +108,7 @@ config PA_BITS
 config PAGE_OFFSET
        hex
        default 0xC0000000 if 32BIT && MAXPHYSMEM_2GB
+       default 0x80000000 if 64BIT && !MMU
        default 0xffffffff80000000 if 64BIT && MAXPHYSMEM_2GB
        default 0xffffffe000000000 if 64BIT && MAXPHYSMEM_128GB
 
@@ -145,7 +152,7 @@ config GENERIC_HWEIGHT
        def_bool y
 
 config FIX_EARLYCON_MEM
-       def_bool y
+       def_bool CONFIG_MMU
 
 config PGTABLE_LEVELS
        int
@@ -170,6 +177,7 @@ config ARCH_RV32I
        select GENERIC_LIB_ASHRDI3
        select GENERIC_LIB_LSHRDI3
        select GENERIC_LIB_UCMPDI2
+       select MMU
 
 config ARCH_RV64I
        bool "RV64I"
@@ -178,9 +186,9 @@ config ARCH_RV64I
        select HAVE_FUNCTION_TRACER
        select HAVE_FUNCTION_GRAPH_TRACER
        select HAVE_FTRACE_MCOUNT_RECORD
-       select HAVE_DYNAMIC_FTRACE
-       select HAVE_DYNAMIC_FTRACE_WITH_REGS
-       select SWIOTLB
+       select HAVE_DYNAMIC_FTRACE if MMU
+       select HAVE_DYNAMIC_FTRACE_WITH_REGS if HAVE_DYNAMIC_FTRACE
+       select SWIOTLB if MMU
 
 endchoice