From 2475ff9d2c6ea3bbfed55c4635426c371f9ad327 Mon Sep 17 00:00:00 2001 From: Catalin Marinas Date: Tue, 23 Oct 2012 14:55:08 +0100 Subject: arm64: Add simple earlyprintk support This patch adds support for "earlyprintk=" parameter on the kernel command line. The format is: earlyprintk=[,][,] where is the name of the (UART) device, e.g. "pl011", is the I/O address. The aren't currently used. The mapping of the earlyprintk device is done very early during kernel boot and there are restrictions on which functions it can call. A special early_io_map() function is added which creates the mapping from the pre-defined EARLY_IOBASE to the device I/O address passed via the kernel parameter. The pgd entry corresponding to EARLY_IOBASE is pre-populated in head.S during kernel boot. Only PL011 is currently supported and it is assumed that the interface is already initialised by the boot loader before the kernel is started. Signed-off-by: Catalin Marinas Acked-by: Arnd Bergmann --- arch/arm64/mm/mmu.c | 42 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 42 insertions(+) (limited to 'arch/arm64/mm/mmu.c') diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c index a6885d896ab6..f4dd585898c5 100644 --- a/arch/arm64/mm/mmu.c +++ b/arch/arm64/mm/mmu.c @@ -25,6 +25,7 @@ #include #include #include +#include #include #include @@ -251,6 +252,47 @@ static void __init create_mapping(phys_addr_t phys, unsigned long virt, } while (pgd++, addr = next, addr != end); } +#ifdef CONFIG_EARLY_PRINTK +/* + * Create an early I/O mapping using the pgd/pmd entries already populated + * in head.S as this function is called too early to allocated any memory. The + * mapping size is 2MB with 4KB pages or 64KB or 64KB pages. + */ +void __iomem * __init early_io_map(phys_addr_t phys, unsigned long virt) +{ + unsigned long size, mask; + bool page64k = IS_ENABLED(ARM64_64K_PAGES); + pgd_t *pgd; + pud_t *pud; + pmd_t *pmd; + pte_t *pte; + + /* + * No early pte entries with !ARM64_64K_PAGES configuration, so using + * sections (pmd). + */ + size = page64k ? PAGE_SIZE : SECTION_SIZE; + mask = ~(size - 1); + + pgd = pgd_offset_k(virt); + pud = pud_offset(pgd, virt); + if (pud_none(*pud)) + return NULL; + pmd = pmd_offset(pud, virt); + + if (page64k) { + if (pmd_none(*pmd)) + return NULL; + pte = pte_offset_kernel(pmd, virt); + set_pte(pte, __pte((phys & mask) | PROT_DEVICE_nGnRE)); + } else { + set_pmd(pmd, __pmd((phys & mask) | PROT_SECT_DEVICE_nGnRE)); + } + + return (void __iomem *)((virt & mask) + (phys & ~mask)); +} +#endif + static void __init map_mem(void) { struct memblock_region *reg; -- cgit v1.2.3 From 0197518cd3672029618a16a57597946a094ac7a8 Mon Sep 17 00:00:00 2001 From: Tang Chen Date: Fri, 22 Feb 2013 16:33:08 -0800 Subject: memory-hotplug: remove memmap of sparse-vmemmap Introduce a new API vmemmap_free() to free and remove vmemmap pagetables. Since pagetable implements are different, each architecture has to provide its own version of vmemmap_free(), just like vmemmap_populate(). Note: vmemmap_free() is not implemented for ia64, ppc, s390, and sparc. [mhocko@suse.cz: fix implicit declaration of remove_pagetable] Signed-off-by: Yasuaki Ishimatsu Signed-off-by: Jianguo Wu Signed-off-by: Wen Congyang Signed-off-by: Tang Chen Cc: KOSAKI Motohiro Cc: Jiang Liu Cc: Kamezawa Hiroyuki Cc: Lai Jiangshan Cc: Wu Jianguo Cc: Ingo Molnar Cc: Thomas Gleixner Cc: "H. Peter Anvin" Signed-off-by: Michal Hocko Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/arm64/mm/mmu.c | 3 +++ arch/ia64/mm/discontig.c | 3 +++ arch/powerpc/mm/init_64.c | 4 ++++ arch/s390/mm/vmem.c | 4 ++++ arch/sparc/mm/init_64.c | 4 ++++ arch/x86/mm/init_64.c | 8 ++++++++ include/linux/mm.h | 3 +++ mm/sparse.c | 3 ++- 8 files changed, 31 insertions(+), 1 deletion(-) (limited to 'arch/arm64/mm/mmu.c') diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c index f4dd585898c5..224b44ab534e 100644 --- a/arch/arm64/mm/mmu.c +++ b/arch/arm64/mm/mmu.c @@ -434,4 +434,7 @@ int __meminit vmemmap_populate(struct page *start_page, return 0; } #endif /* CONFIG_ARM64_64K_PAGES */ +void vmemmap_free(struct page *memmap, unsigned long nr_pages) +{ +} #endif /* CONFIG_SPARSEMEM_VMEMMAP */ diff --git a/arch/ia64/mm/discontig.c b/arch/ia64/mm/discontig.c index 731bf84094b6..652fee097921 100644 --- a/arch/ia64/mm/discontig.c +++ b/arch/ia64/mm/discontig.c @@ -823,4 +823,7 @@ int __meminit vmemmap_populate(struct page *start_page, return vmemmap_populate_basepages(start_page, size, node); } +void vmemmap_free(struct page *memmap, unsigned long nr_pages) +{ +} #endif diff --git a/arch/powerpc/mm/init_64.c b/arch/powerpc/mm/init_64.c index 42bf082f0124..7e2246fb2f31 100644 --- a/arch/powerpc/mm/init_64.c +++ b/arch/powerpc/mm/init_64.c @@ -298,5 +298,9 @@ int __meminit vmemmap_populate(struct page *start_page, return 0; } +void vmemmap_free(struct page *memmap, unsigned long nr_pages) +{ +} + #endif /* CONFIG_SPARSEMEM_VMEMMAP */ diff --git a/arch/s390/mm/vmem.c b/arch/s390/mm/vmem.c index 79699f46a443..e21aaf4f5cb6 100644 --- a/arch/s390/mm/vmem.c +++ b/arch/s390/mm/vmem.c @@ -268,6 +268,10 @@ out: return ret; } +void vmemmap_free(struct page *memmap, unsigned long nr_pages) +{ +} + /* * Add memory segment to the segment list if it doesn't overlap with * an already present segment. diff --git a/arch/sparc/mm/init_64.c b/arch/sparc/mm/init_64.c index 59c6fcfdc782..1588d33d5492 100644 --- a/arch/sparc/mm/init_64.c +++ b/arch/sparc/mm/init_64.c @@ -2236,6 +2236,10 @@ void __meminit vmemmap_populate_print_last(void) } } +void vmemmap_free(struct page *memmap, unsigned long nr_pages) +{ +} + #endif /* CONFIG_SPARSEMEM_VMEMMAP */ static void prot_init_common(unsigned long page_none, diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c index 4e58b83e6b2e..474e28f10815 100644 --- a/arch/x86/mm/init_64.c +++ b/arch/x86/mm/init_64.c @@ -1011,6 +1011,14 @@ remove_pagetable(unsigned long start, unsigned long end, bool direct) flush_tlb_all(); } +void __ref vmemmap_free(struct page *memmap, unsigned long nr_pages) +{ + unsigned long start = (unsigned long)memmap; + unsigned long end = (unsigned long)(memmap + nr_pages); + + remove_pagetable(start, end, false); +} + static void __meminit kernel_physical_mapping_remove(unsigned long start, unsigned long end) { diff --git a/include/linux/mm.h b/include/linux/mm.h index 060557b9764f..9d659491c0ae 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -1718,6 +1718,9 @@ int vmemmap_populate_basepages(struct page *start_page, unsigned long pages, int node); int vmemmap_populate(struct page *start_page, unsigned long pages, int node); void vmemmap_populate_print_last(void); +#ifdef CONFIG_MEMORY_HOTPLUG +void vmemmap_free(struct page *memmap, unsigned long nr_pages); +#endif void register_page_bootmem_memmap(unsigned long section_nr, struct page *map, unsigned long size); diff --git a/mm/sparse.c b/mm/sparse.c index 66f0fd9d7964..46f6ea47d9ab 100644 --- a/mm/sparse.c +++ b/mm/sparse.c @@ -615,10 +615,11 @@ static inline struct page *kmalloc_section_memmap(unsigned long pnum, int nid, } static void __kfree_section_memmap(struct page *memmap, unsigned long nr_pages) { - return; /* XXX: Not implemented yet */ + vmemmap_free(memmap, nr_pages); } static void free_map_bootmem(struct page *memmap, unsigned long nr_pages) { + vmemmap_free(memmap, nr_pages); } #else static struct page *__kmalloc_section_memmap(unsigned long nr_pages) -- cgit v1.2.3