From 76743c0e0915af6ae1d960c14e8c1dcb3e238f23 Mon Sep 17 00:00:00 2001 From: Max Filippov Date: Tue, 1 Oct 2019 00:25:30 -0700 Subject: xtensa: move kernel memory layout to platform options Currently kernel memory layout settings are split between "Processor type and features" and "Platform options" menus. Consolidate them under "Platform options". Signed-off-by: Max Filippov --- arch/xtensa/Kconfig | 348 ++++++++++++++++++++++++++-------------------------- 1 file changed, 175 insertions(+), 173 deletions(-) (limited to 'arch/xtensa') diff --git a/arch/xtensa/Kconfig b/arch/xtensa/Kconfig index a8e7beb6b7b5..ea9f63c7672d 100644 --- a/arch/xtensa/Kconfig +++ b/arch/xtensa/Kconfig @@ -213,151 +213,6 @@ config HOTPLUG_CPU Say N if you want to disable CPU hotplug. -config INITIALIZE_XTENSA_MMU_INSIDE_VMLINUX - bool "Initialize Xtensa MMU inside the Linux kernel code" - depends on !XTENSA_VARIANT_FSF && !XTENSA_VARIANT_DC232B - default y if XTENSA_VARIANT_DC233C || XTENSA_VARIANT_CUSTOM - help - Earlier version initialized the MMU in the exception vector - before jumping to _startup in head.S and had an advantage that - it was possible to place a software breakpoint at 'reset' and - then enter your normal kernel breakpoints once the MMU was mapped - to the kernel mappings (0XC0000000). - - This unfortunately won't work for U-Boot and likely also wont - work for using KEXEC to have a hot kernel ready for doing a - KDUMP. - - So now the MMU is initialized in head.S but it's necessary to - use hardware breakpoints (gdb 'hbreak' cmd) to break at _startup. - xt-gdb can't place a Software Breakpoint in the 0XD region prior - to mapping the MMU and after mapping even if the area of low memory - was mapped gdb wouldn't remove the breakpoint on hitting it as the - PC wouldn't match. Since Hardware Breakpoints are recommended for - Linux configurations it seems reasonable to just assume they exist - and leave this older mechanism for unfortunate souls that choose - not to follow Tensilica's recommendation. - - Selecting this will cause U-Boot to set the KERNEL Load and Entry - address at 0x00003000 instead of the mapped std of 0xD0003000. - - If in doubt, say Y. - -config MEMMAP_CACHEATTR - hex "Cache attributes for the memory address space" - depends on !MMU - default 0x22222222 - help - These cache attributes are set up for noMMU systems. Each hex digit - specifies cache attributes for the corresponding 512MB memory - region: bits 0..3 -- for addresses 0x00000000..0x1fffffff, - bits 4..7 -- for addresses 0x20000000..0x3fffffff, and so on. - - Cache attribute values are specific for the MMU type. - For region protection MMUs: - 1: WT cached, - 2: cache bypass, - 4: WB cached, - f: illegal. - For ful MMU: - bit 0: executable, - bit 1: writable, - bits 2..3: - 0: cache bypass, - 1: WB cache, - 2: WT cache, - 3: special (c and e are illegal, f is reserved). - For MPU: - 0: illegal, - 1: WB cache, - 2: WB, no-write-allocate cache, - 3: WT cache, - 4: cache bypass. - -config KSEG_PADDR - hex "Physical address of the KSEG mapping" - depends on INITIALIZE_XTENSA_MMU_INSIDE_VMLINUX && MMU - default 0x00000000 - help - This is the physical address where KSEG is mapped. Please refer to - the chosen KSEG layout help for the required address alignment. - Unpacked kernel image (including vectors) must be located completely - within KSEG. - Physical memory below this address is not available to linux. - - If unsure, leave the default value here. - -config KERNEL_LOAD_ADDRESS - hex "Kernel load address" - default 0x60003000 if !MMU - default 0x00003000 if MMU && INITIALIZE_XTENSA_MMU_INSIDE_VMLINUX - default 0xd0003000 if MMU && !INITIALIZE_XTENSA_MMU_INSIDE_VMLINUX - help - This is the address where the kernel is loaded. - It is virtual address for MMUv2 configurations and physical address - for all other configurations. - - If unsure, leave the default value here. - -config VECTORS_OFFSET - hex "Kernel vectors offset" - default 0x00003000 - help - This is the offset of the kernel image from the relocatable vectors - base. - - If unsure, leave the default value here. - -choice - prompt "KSEG layout" - depends on MMU - default XTENSA_KSEG_MMU_V2 - -config XTENSA_KSEG_MMU_V2 - bool "MMUv2: 128MB cached + 128MB uncached" - help - MMUv2 compatible kernel memory map: TLB way 5 maps 128MB starting - at KSEG_PADDR to 0xd0000000 with cache and to 0xd8000000 - without cache. - KSEG_PADDR must be aligned to 128MB. - -config XTENSA_KSEG_256M - bool "256MB cached + 256MB uncached" - depends on INITIALIZE_XTENSA_MMU_INSIDE_VMLINUX - help - TLB way 6 maps 256MB starting at KSEG_PADDR to 0xb0000000 - with cache and to 0xc0000000 without cache. - KSEG_PADDR must be aligned to 256MB. - -config XTENSA_KSEG_512M - bool "512MB cached + 512MB uncached" - depends on INITIALIZE_XTENSA_MMU_INSIDE_VMLINUX - help - TLB way 6 maps 512MB starting at KSEG_PADDR to 0xa0000000 - with cache and to 0xc0000000 without cache. - KSEG_PADDR must be aligned to 256MB. - -endchoice - -config HIGHMEM - bool "High Memory Support" - depends on MMU - help - Linux can use the full amount of RAM in the system by - default. However, the default MMUv2 setup only maps the - lowermost 128 MB of memory linearly to the areas starting - at 0xd0000000 (cached) and 0xd8000000 (uncached). - When there are more than 128 MB memory in the system not - all of it can be "permanently mapped" by the kernel. - The physical memory that's not permanently mapped is called - "high memory". - - If you are compiling a kernel which will never run on a - machine with more than 128 MB total physical RAM, answer - N here. - - If unsure, say Y. - config FAST_SYSCALL_XTENSA bool "Enable fast atomic syscalls" default n @@ -561,34 +416,6 @@ config SIMDISK1_FILENAME Another simulated disk in a host file for a buildroot-independent storage. -config FORCE_MAX_ZONEORDER - int "Maximum zone order" - default "11" - help - The kernel memory allocator divides physically contiguous memory - blocks into "zones", where each zone is a power of two number of - pages. This option selects the largest power of two that the kernel - keeps in the memory allocator. If you need to allocate very large - blocks of physically contiguous memory, then you may need to - increase this value. - - This config option is actually maximum order plus one. For example, - a value of 11 means that the largest free memory block is 2^10 pages. - -config PLATFORM_WANT_DEFAULT_MEM - def_bool n - -config DEFAULT_MEM_START - hex - prompt "PAGE_OFFSET/PHYS_OFFSET" if !MMU && PLATFORM_WANT_DEFAULT_MEM - default 0x60000000 if PLATFORM_WANT_DEFAULT_MEM - default 0x00000000 - help - This is the base address used for both PAGE_OFFSET and PHYS_OFFSET - in noMMU configurations. - - If unsure, leave the default value here. - config XTFPGA_LCD bool "Enable XTFPGA LCD driver" depends on XTENSA_PLATFORM_XTFPGA @@ -619,6 +446,181 @@ config XTFPGA_LCD_8BIT_ACCESS only be used with 8-bit interface. Please consult prototyping user guide for your board for the correct interface width. +comment "Kernel memory layout" + +config INITIALIZE_XTENSA_MMU_INSIDE_VMLINUX + bool "Initialize Xtensa MMU inside the Linux kernel code" + depends on !XTENSA_VARIANT_FSF && !XTENSA_VARIANT_DC232B + default y if XTENSA_VARIANT_DC233C || XTENSA_VARIANT_CUSTOM + help + Earlier version initialized the MMU in the exception vector + before jumping to _startup in head.S and had an advantage that + it was possible to place a software breakpoint at 'reset' and + then enter your normal kernel breakpoints once the MMU was mapped + to the kernel mappings (0XC0000000). + + This unfortunately won't work for U-Boot and likely also wont + work for using KEXEC to have a hot kernel ready for doing a + KDUMP. + + So now the MMU is initialized in head.S but it's necessary to + use hardware breakpoints (gdb 'hbreak' cmd) to break at _startup. + xt-gdb can't place a Software Breakpoint in the 0XD region prior + to mapping the MMU and after mapping even if the area of low memory + was mapped gdb wouldn't remove the breakpoint on hitting it as the + PC wouldn't match. Since Hardware Breakpoints are recommended for + Linux configurations it seems reasonable to just assume they exist + and leave this older mechanism for unfortunate souls that choose + not to follow Tensilica's recommendation. + + Selecting this will cause U-Boot to set the KERNEL Load and Entry + address at 0x00003000 instead of the mapped std of 0xD0003000. + + If in doubt, say Y. + +config MEMMAP_CACHEATTR + hex "Cache attributes for the memory address space" + depends on !MMU + default 0x22222222 + help + These cache attributes are set up for noMMU systems. Each hex digit + specifies cache attributes for the corresponding 512MB memory + region: bits 0..3 -- for addresses 0x00000000..0x1fffffff, + bits 4..7 -- for addresses 0x20000000..0x3fffffff, and so on. + + Cache attribute values are specific for the MMU type. + For region protection MMUs: + 1: WT cached, + 2: cache bypass, + 4: WB cached, + f: illegal. + For ful MMU: + bit 0: executable, + bit 1: writable, + bits 2..3: + 0: cache bypass, + 1: WB cache, + 2: WT cache, + 3: special (c and e are illegal, f is reserved). + For MPU: + 0: illegal, + 1: WB cache, + 2: WB, no-write-allocate cache, + 3: WT cache, + 4: cache bypass. + +config KSEG_PADDR + hex "Physical address of the KSEG mapping" + depends on INITIALIZE_XTENSA_MMU_INSIDE_VMLINUX && MMU + default 0x00000000 + help + This is the physical address where KSEG is mapped. Please refer to + the chosen KSEG layout help for the required address alignment. + Unpacked kernel image (including vectors) must be located completely + within KSEG. + Physical memory below this address is not available to linux. + + If unsure, leave the default value here. + +config KERNEL_LOAD_ADDRESS + hex "Kernel load address" + default 0x60003000 if !MMU + default 0x00003000 if MMU && INITIALIZE_XTENSA_MMU_INSIDE_VMLINUX + default 0xd0003000 if MMU && !INITIALIZE_XTENSA_MMU_INSIDE_VMLINUX + help + This is the address where the kernel is loaded. + It is virtual address for MMUv2 configurations and physical address + for all other configurations. + + If unsure, leave the default value here. + +config VECTORS_OFFSET + hex "Kernel vectors offset" + default 0x00003000 + help + This is the offset of the kernel image from the relocatable vectors + base. + + If unsure, leave the default value here. + +config PLATFORM_WANT_DEFAULT_MEM + def_bool n + +config DEFAULT_MEM_START + hex + prompt "PAGE_OFFSET/PHYS_OFFSET" if !MMU && PLATFORM_WANT_DEFAULT_MEM + default 0x60000000 if PLATFORM_WANT_DEFAULT_MEM + default 0x00000000 + help + This is the base address used for both PAGE_OFFSET and PHYS_OFFSET + in noMMU configurations. + + If unsure, leave the default value here. + +choice + prompt "KSEG layout" + depends on MMU + default XTENSA_KSEG_MMU_V2 + +config XTENSA_KSEG_MMU_V2 + bool "MMUv2: 128MB cached + 128MB uncached" + help + MMUv2 compatible kernel memory map: TLB way 5 maps 128MB starting + at KSEG_PADDR to 0xd0000000 with cache and to 0xd8000000 + without cache. + KSEG_PADDR must be aligned to 128MB. + +config XTENSA_KSEG_256M + bool "256MB cached + 256MB uncached" + depends on INITIALIZE_XTENSA_MMU_INSIDE_VMLINUX + help + TLB way 6 maps 256MB starting at KSEG_PADDR to 0xb0000000 + with cache and to 0xc0000000 without cache. + KSEG_PADDR must be aligned to 256MB. + +config XTENSA_KSEG_512M + bool "512MB cached + 512MB uncached" + depends on INITIALIZE_XTENSA_MMU_INSIDE_VMLINUX + help + TLB way 6 maps 512MB starting at KSEG_PADDR to 0xa0000000 + with cache and to 0xc0000000 without cache. + KSEG_PADDR must be aligned to 256MB. + +endchoice + +config HIGHMEM + bool "High Memory Support" + depends on MMU + help + Linux can use the full amount of RAM in the system by + default. However, the default MMUv2 setup only maps the + lowermost 128 MB of memory linearly to the areas starting + at 0xd0000000 (cached) and 0xd8000000 (uncached). + When there are more than 128 MB memory in the system not + all of it can be "permanently mapped" by the kernel. + The physical memory that's not permanently mapped is called + "high memory". + + If you are compiling a kernel which will never run on a + machine with more than 128 MB total physical RAM, answer + N here. + + If unsure, say Y. + +config FORCE_MAX_ZONEORDER + int "Maximum zone order" + default "11" + help + The kernel memory allocator divides physically contiguous memory + blocks into "zones", where each zone is a power of two number of + pages. This option selects the largest power of two that the kernel + keeps in the memory allocator. If you need to allocate very large + blocks of physically contiguous memory, then you may need to + increase this value. + + This config option is actually maximum order plus one. For example, + a value of 11 means that the largest free memory block is 2^10 pages. + endmenu menu "Power management options" -- cgit v1.2.3-59-g8ed1b