diff options
| -rw-r--r-- | arch/openrisc/Kconfig | 11 | ||||
| -rw-r--r-- | arch/openrisc/include/asm/Kbuild | 1 | ||||
| -rw-r--r-- | arch/openrisc/include/asm/cacheflush.h | 96 | ||||
| -rw-r--r-- | arch/openrisc/include/asm/pgtable.h | 16 | ||||
| -rw-r--r-- | arch/openrisc/kernel/smp.c | 15 | ||||
| -rw-r--r-- | arch/openrisc/mm/Makefile | 2 | ||||
| -rw-r--r-- | arch/openrisc/mm/cache.c | 61 |
7 files changed, 194 insertions, 8 deletions
diff --git a/arch/openrisc/Kconfig b/arch/openrisc/Kconfig index 2b3898ede888..bfff04ae7f7d 100644 --- a/arch/openrisc/Kconfig +++ b/arch/openrisc/Kconfig @@ -77,6 +77,17 @@ config OR1K_1200 endchoice +config DCACHE_WRITETHROUGH + bool "Have write through data caches" + default n + help + Select this if your implementation features write through data caches. + Selecting 'N' here will allow the kernel to force flushing of data + caches at relevant times. Most OpenRISC implementations support write- + through data caches. + + If unsure say N here + config OPENRISC_BUILTIN_DTB string "Builtin DTB" default "" diff --git a/arch/openrisc/include/asm/Kbuild b/arch/openrisc/include/asm/Kbuild index 5f066780d870..6eb16719549e 100644 --- a/arch/openrisc/include/asm/Kbuild +++ b/arch/openrisc/include/asm/Kbuild @@ -1,7 +1,6 @@ generic-y += barrier.h generic-y += bug.h generic-y += bugs.h -generic-y += cacheflush.h generic-y += checksum.h generic-y += clkdev.h generic-y += current.h diff --git a/arch/openrisc/include/asm/cacheflush.h b/arch/openrisc/include/asm/cacheflush.h new file mode 100644 index 000000000000..70f46fd7a074 --- /dev/null +++ b/arch/openrisc/include/asm/cacheflush.h @@ -0,0 +1,96 @@ +/* + * OpenRISC Linux + * + * Linux architectural port borrowing liberally from similar works of + * others. All original copyrights apply as per the original source + * declaration. + * + * OpenRISC implementation: + * Copyright (C) Jan Henrik Weinstock <jan.weinstock@rwth-aachen.de> + * et al. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + */ + +#ifndef __ASM_CACHEFLUSH_H +#define __ASM_CACHEFLUSH_H + +#include <linux/mm.h> + +/* + * Helper function for flushing or invalidating entire pages from data + * and instruction caches. SMP needs a little extra work, since we need + * to flush the pages on all cpus. + */ +extern void local_dcache_page_flush(struct page *page); +extern void local_icache_page_inv(struct page *page); + +/* + * Data cache flushing always happen on the local cpu. Instruction cache + * invalidations need to be broadcasted to all other cpu in the system in + * case of SMP configurations. + */ +#ifndef CONFIG_SMP +#define dcache_page_flush(page) local_dcache_page_flush(page) +#define icache_page_inv(page) local_icache_page_inv(page) +#else /* CONFIG_SMP */ +#define dcache_page_flush(page) local_dcache_page_flush(page) +#define icache_page_inv(page) smp_icache_page_inv(page) +extern void smp_icache_page_inv(struct page *page); +#endif /* CONFIG_SMP */ + +/* + * Synchronizes caches. Whenever a cpu writes executable code to memory, this + * should be called to make sure the processor sees the newly written code. + */ +static inline void sync_icache_dcache(struct page *page) +{ + if (!IS_ENABLED(CONFIG_DCACHE_WRITETHROUGH)) + dcache_page_flush(page); + icache_page_inv(page); +} + +/* + * Pages with this bit set need not be flushed/invalidated, since + * they have not changed since last flush. New pages start with + * PG_arch_1 not set and are therefore dirty by default. + */ +#define PG_dc_clean PG_arch_1 + +#define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 1 +static inline void flush_dcache_page(struct page *page) +{ + clear_bit(PG_dc_clean, &page->flags); +} + +/* + * Other interfaces are not required since we do not have virtually + * indexed or tagged caches. So we can use the default here. + */ +#define flush_cache_all() do { } while (0) +#define flush_cache_mm(mm) do { } while (0) +#define flush_cache_dup_mm(mm) do { } while (0) +#define flush_cache_range(vma, start, end) do { } while (0) +#define flush_cache_page(vma, vmaddr, pfn) do { } while (0) +#define flush_dcache_mmap_lock(mapping) do { } while (0) +#define flush_dcache_mmap_unlock(mapping) do { } while (0) +#define flush_icache_range(start, end) do { } while (0) +#define flush_icache_page(vma, pg) do { } while (0) +#define flush_icache_user_range(vma, pg, adr, len) do { } while (0) +#define flush_cache_vmap(start, end) do { } while (0) +#define flush_cache_vunmap(start, end) do { } while (0) + +#define copy_to_user_page(vma, page, vaddr, dst, src, len) \ + do { \ + memcpy(dst, src, len); \ + if (vma->vm_flags & VM_EXEC) \ + sync_icache_dcache(page); \ + } while (0) + +#define copy_from_user_page(vma, page, vaddr, dst, src, len) \ + memcpy(dst, src, len) + +#endif /* __ASM_CACHEFLUSH_H */ diff --git a/arch/openrisc/include/asm/pgtable.h b/arch/openrisc/include/asm/pgtable.h index eff5ba2a5af2..21c71303012f 100644 --- a/arch/openrisc/include/asm/pgtable.h +++ b/arch/openrisc/include/asm/pgtable.h @@ -416,15 +416,19 @@ extern pgd_t swapper_pg_dir[PTRS_PER_PGD]; /* defined in head.S */ struct vm_area_struct; -/* - * or32 doesn't have any external MMU info: the kernel page - * tables contain all the necessary information. - * - * Actually I am not sure on what this could be used for. - */ +static inline void update_tlb(struct vm_area_struct *vma, + unsigned long address, pte_t *pte) +{ +} + +extern void update_cache(struct vm_area_struct *vma, + unsigned long address, pte_t *pte); + static inline void update_mmu_cache(struct vm_area_struct *vma, unsigned long address, pte_t *pte) { + update_tlb(vma, address, pte); + update_cache(vma, address, pte); } /* __PHX__ FIXME, SWAP, this probably doesn't work */ diff --git a/arch/openrisc/kernel/smp.c b/arch/openrisc/kernel/smp.c index 685b4934fa39..4763b8b9161e 100644 --- a/arch/openrisc/kernel/smp.c +++ b/arch/openrisc/kernel/smp.c @@ -18,6 +18,7 @@ #include <asm/cpuinfo.h> #include <asm/mmu_context.h> #include <asm/tlbflush.h> +#include <asm/cacheflush.h> #include <asm/time.h> static void (*smp_cross_call)(const struct cpumask *, unsigned int); @@ -239,3 +240,17 @@ void flush_tlb_range(struct vm_area_struct *vma, { on_each_cpu(ipi_flush_tlb_all, NULL, 1); } + +/* Instruction cache invalidate - performed on each cpu */ +static void ipi_icache_page_inv(void *arg) +{ + struct page *page = arg; + + local_icache_page_inv(page); +} + +void smp_icache_page_inv(struct page *page) +{ + on_each_cpu(ipi_icache_page_inv, page, 1); +} +EXPORT_SYMBOL(smp_icache_page_inv); diff --git a/arch/openrisc/mm/Makefile b/arch/openrisc/mm/Makefile index 324ba2634529..a31b2a42e966 100644 --- a/arch/openrisc/mm/Makefile +++ b/arch/openrisc/mm/Makefile @@ -2,4 +2,4 @@ # Makefile for the linux openrisc-specific parts of the memory manager. # -obj-y := fault.o tlb.o init.o ioremap.o +obj-y := fault.o cache.o tlb.o init.o ioremap.o diff --git a/arch/openrisc/mm/cache.c b/arch/openrisc/mm/cache.c new file mode 100644 index 000000000000..b747bf1fc1b6 --- /dev/null +++ b/arch/openrisc/mm/cache.c @@ -0,0 +1,61 @@ +/* + * OpenRISC cache.c + * + * Linux architectural port borrowing liberally from similar works of + * others. All original copyrights apply as per the original source + * declaration. + * + * Modifications for the OpenRISC architecture: + * Copyright (C) 2015 Jan Henrik Weinstock <jan.weinstock@rwth-aachen.de> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + */ + +#include <asm/spr.h> +#include <asm/spr_defs.h> +#include <asm/cache.h> +#include <asm/cacheflush.h> +#include <asm/tlbflush.h> + +static void cache_loop(struct page *page, const unsigned int reg) +{ + unsigned long paddr = page_to_pfn(page) << PAGE_SHIFT; + unsigned long line = paddr & ~(L1_CACHE_BYTES - 1); + + while (line < paddr + PAGE_SIZE) { + mtspr(reg, line); + line += L1_CACHE_BYTES; + } +} + +void local_dcache_page_flush(struct page *page) +{ + cache_loop(page, SPR_DCBFR); +} +EXPORT_SYMBOL(local_dcache_page_flush); + +void local_icache_page_inv(struct page *page) +{ + cache_loop(page, SPR_ICBIR); +} +EXPORT_SYMBOL(local_icache_page_inv); + +void update_cache(struct vm_area_struct *vma, unsigned long address, + pte_t *pte) +{ + unsigned long pfn = pte_val(*pte) >> PAGE_SHIFT; + struct page *page = pfn_to_page(pfn); + int dirty = !test_and_set_bit(PG_dc_clean, &page->flags); + + /* + * Since icaches do not snoop for updated data on OpenRISC, we + * must write back and invalidate any dirty pages manually. We + * can skip data pages, since they will not end up in icaches. + */ + if ((vma->vm_flags & VM_EXEC) && dirty) + sync_icache_dcache(page); +} + |