From d39af90265feb40ec198c4ca8268724645b4b50e Mon Sep 17 00:00:00 2001 From: Max Filippov Date: Mon, 11 Apr 2016 21:14:17 +0300 Subject: [PATCH] xtensa: add alternative kernel memory layouts MMUv3 is able to support low memory bigger than 128MB. Implement 256MB and 512MB KSEG layouts: - add Kconfig selector for KSEG layout; - add KSEG base address, size and alignment definitions to arch/xtensa/include/asm/kmem_layout.h; - use new definitions in TLB initialization; - add build time memory map consistency checks. See Documentation/xtensa/mmu.txt for the details of new memory layouts. Signed-off-by: Max Filippov --- Documentation/xtensa/mmu.txt | 124 +++++++++++++++++++++++ arch/xtensa/Kconfig | 44 ++++++++ arch/xtensa/include/asm/fixmap.h | 5 + arch/xtensa/include/asm/highmem.h | 5 + arch/xtensa/include/asm/initialize_mmu.h | 23 ++++- arch/xtensa/include/asm/kmem_layout.h | 46 +++++++++ arch/xtensa/include/asm/page.h | 6 +- arch/xtensa/include/uapi/asm/types.h | 3 +- arch/xtensa/mm/init.c | 3 +- 9 files changed, 249 insertions(+), 10 deletions(-) diff --git a/Documentation/xtensa/mmu.txt b/Documentation/xtensa/mmu.txt index 0312fe66475c..867c0f837e28 100644 --- a/Documentation/xtensa/mmu.txt +++ b/Documentation/xtensa/mmu.txt @@ -62,3 +62,127 @@ limitations apply: 6. The IO area covers the entire 256MB segment of parent-bus-address; the "ranges" triplet length field is ignored + + +MMUv3 address space layouts. +============================ + +Default MMUv2-compatible layout. + + Symbol VADDR Size ++------------------+ +| Userspace | 0x00000000 TASK_SIZE ++------------------+ 0x40000000 ++------------------+ +| Page table | 0x80000000 ++------------------+ 0x80400000 ++------------------+ +| KMAP area | PKMAP_BASE PTRS_PER_PTE * +| | DCACHE_N_COLORS * +| | PAGE_SIZE +| | (4MB * DCACHE_N_COLORS) ++------------------+ +| Atomic KMAP area | FIXADDR_START KM_TYPE_NR * +| | NR_CPUS * +| | DCACHE_N_COLORS * +| | PAGE_SIZE ++------------------+ FIXADDR_TOP 0xbffff000 ++------------------+ +| VMALLOC area | VMALLOC_START 0xc0000000 128MB - 64KB ++------------------+ VMALLOC_END +| Cache aliasing | TLBTEMP_BASE_1 0xc7ff0000 DCACHE_WAY_SIZE +| remap area 1 | ++------------------+ +| Cache aliasing | TLBTEMP_BASE_2 DCACHE_WAY_SIZE +| remap area 2 | ++------------------+ ++------------------+ +| Cached KSEG | XCHAL_KSEG_CACHED_VADDR 0xd0000000 128MB ++------------------+ +| Uncached KSEG | XCHAL_KSEG_BYPASS_VADDR 0xd8000000 128MB ++------------------+ +| Cached KIO | XCHAL_KIO_CACHED_VADDR 0xe0000000 256MB ++------------------+ +| Uncached KIO | XCHAL_KIO_BYPASS_VADDR 0xf0000000 256MB ++------------------+ + + +256MB cached + 256MB uncached layout. + + Symbol VADDR Size ++------------------+ +| Userspace | 0x00000000 TASK_SIZE ++------------------+ 0x40000000 ++------------------+ +| Page table | 0x80000000 ++------------------+ 0x80400000 ++------------------+ +| KMAP area | PKMAP_BASE PTRS_PER_PTE * +| | DCACHE_N_COLORS * +| | PAGE_SIZE +| | (4MB * DCACHE_N_COLORS) ++------------------+ +| Atomic KMAP area | FIXADDR_START KM_TYPE_NR * +| | NR_CPUS * +| | DCACHE_N_COLORS * +| | PAGE_SIZE ++------------------+ FIXADDR_TOP 0x9ffff000 ++------------------+ +| VMALLOC area | VMALLOC_START 0xa0000000 128MB - 64KB ++------------------+ VMALLOC_END +| Cache aliasing | TLBTEMP_BASE_1 0xa7ff0000 DCACHE_WAY_SIZE +| remap area 1 | ++------------------+ +| Cache aliasing | TLBTEMP_BASE_2 DCACHE_WAY_SIZE +| remap area 2 | ++------------------+ ++------------------+ +| Cached KSEG | XCHAL_KSEG_CACHED_VADDR 0xb0000000 256MB ++------------------+ +| Uncached KSEG | XCHAL_KSEG_BYPASS_VADDR 0xc0000000 256MB ++------------------+ ++------------------+ +| Cached KIO | XCHAL_KIO_CACHED_VADDR 0xe0000000 256MB ++------------------+ +| Uncached KIO | XCHAL_KIO_BYPASS_VADDR 0xf0000000 256MB ++------------------+ + + +512MB cached + 512MB uncached layout. + + Symbol VADDR Size ++------------------+ +| Userspace | 0x00000000 TASK_SIZE ++------------------+ 0x40000000 ++------------------+ +| Page table | 0x80000000 ++------------------+ 0x80400000 ++------------------+ +| KMAP area | PKMAP_BASE PTRS_PER_PTE * +| | DCACHE_N_COLORS * +| | PAGE_SIZE +| | (4MB * DCACHE_N_COLORS) ++------------------+ +| Atomic KMAP area | FIXADDR_START KM_TYPE_NR * +| | NR_CPUS * +| | DCACHE_N_COLORS * +| | PAGE_SIZE ++------------------+ FIXADDR_TOP 0x8ffff000 ++------------------+ +| VMALLOC area | VMALLOC_START 0x90000000 128MB - 64KB ++------------------+ VMALLOC_END +| Cache aliasing | TLBTEMP_BASE_1 0x97ff0000 DCACHE_WAY_SIZE +| remap area 1 | ++------------------+ +| Cache aliasing | TLBTEMP_BASE_2 DCACHE_WAY_SIZE +| remap area 2 | ++------------------+ ++------------------+ +| Cached KSEG | XCHAL_KSEG_CACHED_VADDR 0xa0000000 512MB ++------------------+ +| Uncached KSEG | XCHAL_KSEG_BYPASS_VADDR 0xc0000000 512MB ++------------------+ +| Cached KIO | XCHAL_KIO_CACHED_VADDR 0xe0000000 256MB ++------------------+ +| Uncached KIO | XCHAL_KIO_BYPASS_VADDR 0xf0000000 256MB ++------------------+ diff --git a/arch/xtensa/Kconfig b/arch/xtensa/Kconfig index 64336f666fb6..c17496bc37f0 100644 --- a/arch/xtensa/Kconfig +++ b/arch/xtensa/Kconfig @@ -236,6 +236,50 @@ config INITIALIZE_XTENSA_MMU_INSIDE_VMLINUX If in doubt, say Y. +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. + +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 diff --git a/arch/xtensa/include/asm/fixmap.h b/arch/xtensa/include/asm/fixmap.h index 62b507deea9d..0d30403b6c95 100644 --- a/arch/xtensa/include/asm/fixmap.h +++ b/arch/xtensa/include/asm/fixmap.h @@ -59,6 +59,11 @@ enum fixed_addresses { */ static __always_inline unsigned long fix_to_virt(const unsigned int idx) { + /* Check if this memory layout is broken because fixmap overlaps page + * table. + */ + BUILD_BUG_ON(FIXADDR_START < + XCHAL_PAGE_TABLE_VADDR + XCHAL_PAGE_TABLE_SIZE); BUILD_BUG_ON(idx >= __end_of_fixed_addresses); return __fix_to_virt(idx); } diff --git a/arch/xtensa/include/asm/highmem.h b/arch/xtensa/include/asm/highmem.h index 01cef6b40829..6e070db1022e 100644 --- a/arch/xtensa/include/asm/highmem.h +++ b/arch/xtensa/include/asm/highmem.h @@ -68,6 +68,11 @@ void kunmap_high(struct page *page); static inline void *kmap(struct page *page) { + /* Check if this memory layout is broken because PKMAP overlaps + * page table. + */ + BUILD_BUG_ON(PKMAP_BASE < + XCHAL_PAGE_TABLE_VADDR + XCHAL_PAGE_TABLE_SIZE); BUG_ON(in_interrupt()); if (!PageHighMem(page)) return page_address(page); diff --git a/arch/xtensa/include/asm/initialize_mmu.h b/arch/xtensa/include/asm/initialize_mmu.h index 7a1e075969a3..46d4bef61655 100644 --- a/arch/xtensa/include/asm/initialize_mmu.h +++ b/arch/xtensa/include/asm/initialize_mmu.h @@ -116,22 +116,35 @@ add a5, a5, a4 bne a5, a2, 3b - /* Step 4: Setup MMU with the old V2 mappings. */ + /* Step 4: Setup MMU with the requested static mappings. */ + movi a6, 0x01000000 wsr a6, ITLBCFG wsr a6, DTLBCFG isync - movi a5, 0xd0000005 - movi a4, CA_WRITEBACK + movi a5, XCHAL_KSEG_CACHED_VADDR + XCHAL_KSEG_TLB_WAY + movi a4, XCHAL_KSEG_PADDR + CA_WRITEBACK + wdtlb a4, a5 + witlb a4, a5 + + movi a5, XCHAL_KSEG_BYPASS_VADDR + XCHAL_KSEG_TLB_WAY + movi a4, XCHAL_KSEG_PADDR + CA_BYPASS wdtlb a4, a5 witlb a4, a5 - movi a5, 0xd8000005 - movi a4, CA_BYPASS +#ifdef CONFIG_XTENSA_KSEG_512M + movi a5, XCHAL_KSEG_CACHED_VADDR + 0x10000000 + XCHAL_KSEG_TLB_WAY + movi a4, XCHAL_KSEG_PADDR + 0x10000000 + CA_WRITEBACK wdtlb a4, a5 witlb a4, a5 + movi a5, XCHAL_KSEG_BYPASS_VADDR + 0x10000000 + XCHAL_KSEG_TLB_WAY + movi a4, XCHAL_KSEG_PADDR + 0x10000000 + CA_BYPASS + wdtlb a4, a5 + witlb a4, a5 +#endif + movi a5, XCHAL_KIO_CACHED_VADDR + 6 movi a4, XCHAL_KIO_DEFAULT_PADDR + CA_WRITEBACK wdtlb a4, a5 diff --git a/arch/xtensa/include/asm/kmem_layout.h b/arch/xtensa/include/asm/kmem_layout.h index 4eb43b65a34d..bfce7ee8efd8 100644 --- a/arch/xtensa/include/asm/kmem_layout.h +++ b/arch/xtensa/include/asm/kmem_layout.h @@ -13,13 +13,59 @@ #include +#ifdef CONFIG_MMU + /* * Fixed TLB translations in the processor. */ +#define XCHAL_PAGE_TABLE_VADDR __XTENSA_UL_CONST(0x80000000) +#define XCHAL_PAGE_TABLE_SIZE __XTENSA_UL_CONST(0x00400000) + +#if defined(CONFIG_XTENSA_KSEG_MMU_V2) + #define XCHAL_KSEG_CACHED_VADDR __XTENSA_UL_CONST(0xd0000000) #define XCHAL_KSEG_BYPASS_VADDR __XTENSA_UL_CONST(0xd8000000) #define XCHAL_KSEG_SIZE __XTENSA_UL_CONST(0x08000000) +#define XCHAL_KSEG_ALIGNMENT __XTENSA_UL_CONST(0x08000000) +#define XCHAL_KSEG_TLB_WAY 5 + +#elif defined(CONFIG_XTENSA_KSEG_256M) + +#define XCHAL_KSEG_CACHED_VADDR __XTENSA_UL_CONST(0xb0000000) +#define XCHAL_KSEG_BYPASS_VADDR __XTENSA_UL_CONST(0xc0000000) +#define XCHAL_KSEG_SIZE __XTENSA_UL_CONST(0x10000000) +#define XCHAL_KSEG_ALIGNMENT __XTENSA_UL_CONST(0x10000000) +#define XCHAL_KSEG_TLB_WAY 6 + +#elif defined(CONFIG_XTENSA_KSEG_512M) + +#define XCHAL_KSEG_CACHED_VADDR __XTENSA_UL_CONST(0xa0000000) +#define XCHAL_KSEG_BYPASS_VADDR __XTENSA_UL_CONST(0xc0000000) +#define XCHAL_KSEG_SIZE __XTENSA_UL_CONST(0x20000000) +#define XCHAL_KSEG_ALIGNMENT __XTENSA_UL_CONST(0x10000000) +#define XCHAL_KSEG_TLB_WAY 6 + +#else +#error Unsupported KSEG configuration +#endif + +#ifdef CONFIG_KSEG_PADDR +#define XCHAL_KSEG_PADDR __XTENSA_UL_CONST(CONFIG_KSEG_PADDR) +#else #define XCHAL_KSEG_PADDR __XTENSA_UL_CONST(0x00000000) +#endif + +#if XCHAL_KSEG_PADDR & (XCHAL_KSEG_ALIGNMENT - 1) +#error XCHAL_KSEG_PADDR is not properly aligned to XCHAL_KSEG_ALIGNMENT +#endif + +#else + +#define XCHAL_KSEG_CACHED_VADDR __XTENSA_UL_CONST(0xd0000000) +#define XCHAL_KSEG_BYPASS_VADDR __XTENSA_UL_CONST(0xd8000000) +#define XCHAL_KSEG_SIZE __XTENSA_UL_CONST(0x08000000) + +#endif #endif diff --git a/arch/xtensa/include/asm/page.h b/arch/xtensa/include/asm/page.h index fd12a1977ba8..8a02438232c4 100644 --- a/arch/xtensa/include/asm/page.h +++ b/arch/xtensa/include/asm/page.h @@ -27,10 +27,12 @@ #ifdef CONFIG_MMU #define PAGE_OFFSET XCHAL_KSEG_CACHED_VADDR -#define MAX_MEM_PFN XCHAL_KSEG_SIZE +#define MAX_LOW_PFN (PHYS_PFN(XCHAL_KSEG_PADDR) + \ + PHYS_PFN(XCHAL_KSEG_SIZE)) #else #define PAGE_OFFSET __XTENSA_UL_CONST(0) -#define MAX_MEM_PFN (PLATFORM_DEFAULT_MEM_START + PLATFORM_DEFAULT_MEM_SIZE) +#define MAX_LOW_PFN (PHYS_PFN(PLATFORM_DEFAULT_MEM_START) + \ + PHYS_PFN(PLATFORM_DEFAULT_MEM_SIZE)) #endif #define PGTABLE_START 0x80000000 diff --git a/arch/xtensa/include/uapi/asm/types.h b/arch/xtensa/include/uapi/asm/types.h index 87ec7ae73cb1..2efc921506c4 100644 --- a/arch/xtensa/include/uapi/asm/types.h +++ b/arch/xtensa/include/uapi/asm/types.h @@ -18,7 +18,8 @@ # define __XTENSA_UL_CONST(x) x #else # define __XTENSA_UL(x) ((unsigned long)(x)) -# define __XTENSA_UL_CONST(x) x##UL +# define ___XTENSA_UL_CONST(x) x##UL +# define __XTENSA_UL_CONST(x) ___XTENSA_UL_CONST(x) #endif #ifndef __ASSEMBLY__ diff --git a/arch/xtensa/mm/init.c b/arch/xtensa/mm/init.c index 4d7142beac72..302fa72d0d5a 100644 --- a/arch/xtensa/mm/init.c +++ b/arch/xtensa/mm/init.c @@ -266,8 +266,7 @@ void __init bootmem_init(void) if (min_low_pfn > max_pfn) panic("No memory found!\n"); - max_low_pfn = max_pfn < MAX_MEM_PFN >> PAGE_SHIFT ? - max_pfn : MAX_MEM_PFN >> PAGE_SHIFT; + max_low_pfn = min(max_pfn, MAX_LOW_PFN); /* Find an area to use for the bootmem bitmap. */ -- GitLab