From 2c3c1048746a4622d8c89a29670120dc8fab93c4 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 7 Apr 2024 20:49:45 +0200 Subject: Adding upstream version 6.1.76. Signed-off-by: Daniel Baumann --- arch/powerpc/mm/cacheflush.c | 234 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 234 insertions(+) create mode 100644 arch/powerpc/mm/cacheflush.c (limited to 'arch/powerpc/mm/cacheflush.c') diff --git a/arch/powerpc/mm/cacheflush.c b/arch/powerpc/mm/cacheflush.c new file mode 100644 index 000000000..0e9b4879c --- /dev/null +++ b/arch/powerpc/mm/cacheflush.c @@ -0,0 +1,234 @@ +// SPDX-License-Identifier: GPL-2.0-or-later + +#include +#include + +/** + * flush_coherent_icache() - if a CPU has a coherent icache, flush it + * Return true if the cache was flushed, false otherwise + */ +static inline bool flush_coherent_icache(void) +{ + /* + * For a snooping icache, we still need a dummy icbi to purge all the + * prefetched instructions from the ifetch buffers. We also need a sync + * before the icbi to order the actual stores to memory that might + * have modified instructions with the icbi. + */ + if (cpu_has_feature(CPU_FTR_COHERENT_ICACHE)) { + mb(); /* sync */ + icbi((void *)PAGE_OFFSET); + mb(); /* sync */ + isync(); + return true; + } + + return false; +} + +/** + * invalidate_icache_range() - Flush the icache by issuing icbi across an address range + * @start: the start address + * @stop: the stop address (exclusive) + */ +static void invalidate_icache_range(unsigned long start, unsigned long stop) +{ + unsigned long shift = l1_icache_shift(); + unsigned long bytes = l1_icache_bytes(); + char *addr = (char *)(start & ~(bytes - 1)); + unsigned long size = stop - (unsigned long)addr + (bytes - 1); + unsigned long i; + + for (i = 0; i < size >> shift; i++, addr += bytes) + icbi(addr); + + mb(); /* sync */ + isync(); +} + +/** + * flush_icache_range: Write any modified data cache blocks out to memory + * and invalidate the corresponding blocks in the instruction cache + * + * Generic code will call this after writing memory, before executing from it. + * + * @start: the start address + * @stop: the stop address (exclusive) + */ +void flush_icache_range(unsigned long start, unsigned long stop) +{ + if (flush_coherent_icache()) + return; + + clean_dcache_range(start, stop); + + if (IS_ENABLED(CONFIG_44x)) { + /* + * Flash invalidate on 44x because we are passed kmapped + * addresses and this doesn't work for userspace pages due to + * the virtually tagged icache. + */ + iccci((void *)start); + mb(); /* sync */ + isync(); + } else + invalidate_icache_range(start, stop); +} +EXPORT_SYMBOL(flush_icache_range); + +#ifdef CONFIG_HIGHMEM +/** + * flush_dcache_icache_phys() - Flush a page by it's physical address + * @physaddr: the physical address of the page + */ +static void flush_dcache_icache_phys(unsigned long physaddr) +{ + unsigned long bytes = l1_dcache_bytes(); + unsigned long nb = PAGE_SIZE / bytes; + unsigned long addr = physaddr & PAGE_MASK; + unsigned long msr, msr0; + unsigned long loop1 = addr, loop2 = addr; + + msr0 = mfmsr(); + msr = msr0 & ~MSR_DR; + /* + * This must remain as ASM to prevent potential memory accesses + * while the data MMU is disabled + */ + asm volatile( + " mtctr %2;\n" + " mtmsr %3;\n" + " isync;\n" + "0: dcbst 0, %0;\n" + " addi %0, %0, %4;\n" + " bdnz 0b;\n" + " sync;\n" + " mtctr %2;\n" + "1: icbi 0, %1;\n" + " addi %1, %1, %4;\n" + " bdnz 1b;\n" + " sync;\n" + " mtmsr %5;\n" + " isync;\n" + : "+&r" (loop1), "+&r" (loop2) + : "r" (nb), "r" (msr), "i" (bytes), "r" (msr0) + : "ctr", "memory"); +} +NOKPROBE_SYMBOL(flush_dcache_icache_phys) +#else +static void flush_dcache_icache_phys(unsigned long physaddr) +{ +} +#endif + +/** + * __flush_dcache_icache(): Flush a particular page from the data cache to RAM. + * Note: this is necessary because the instruction cache does *not* + * snoop from the data cache. + * + * @p: the address of the page to flush + */ +static void __flush_dcache_icache(void *p) +{ + unsigned long addr = (unsigned long)p & PAGE_MASK; + + clean_dcache_range(addr, addr + PAGE_SIZE); + + /* + * We don't flush the icache on 44x. Those have a virtual icache and we + * don't have access to the virtual address here (it's not the page + * vaddr but where it's mapped in user space). The flushing of the + * icache on these is handled elsewhere, when a change in the address + * space occurs, before returning to user space. + */ + + if (mmu_has_feature(MMU_FTR_TYPE_44x)) + return; + + invalidate_icache_range(addr, addr + PAGE_SIZE); +} + +static void flush_dcache_icache_hugepage(struct page *page) +{ + int i; + int nr = compound_nr(page); + + if (!PageHighMem(page)) { + for (i = 0; i < nr; i++) + __flush_dcache_icache(lowmem_page_address(page + i)); + } else { + for (i = 0; i < nr; i++) { + void *start = kmap_local_page(page + i); + + __flush_dcache_icache(start); + kunmap_local(start); + } + } +} + +void flush_dcache_icache_page(struct page *page) +{ + if (flush_coherent_icache()) + return; + + if (PageCompound(page)) + return flush_dcache_icache_hugepage(page); + + if (!PageHighMem(page)) { + __flush_dcache_icache(lowmem_page_address(page)); + } else if (IS_ENABLED(CONFIG_BOOKE) || sizeof(phys_addr_t) > sizeof(void *)) { + void *start = kmap_local_page(page); + + __flush_dcache_icache(start); + kunmap_local(start); + } else { + flush_dcache_icache_phys(page_to_phys(page)); + } +} +EXPORT_SYMBOL(flush_dcache_icache_page); + +void clear_user_page(void *page, unsigned long vaddr, struct page *pg) +{ + clear_page(page); + + /* + * We shouldn't have to do this, but some versions of glibc + * require it (ld.so assumes zero filled pages are icache clean) + * - Anton + */ + flush_dcache_page(pg); +} +EXPORT_SYMBOL(clear_user_page); + +void copy_user_page(void *vto, void *vfrom, unsigned long vaddr, + struct page *pg) +{ + copy_page(vto, vfrom); + + /* + * We should be able to use the following optimisation, however + * there are two problems. + * Firstly a bug in some versions of binutils meant PLT sections + * were not marked executable. + * Secondly the first word in the GOT section is blrl, used + * to establish the GOT address. Until recently the GOT was + * not marked executable. + * - Anton + */ +#if 0 + if (!vma->vm_file && ((vma->vm_flags & VM_EXEC) == 0)) + return; +#endif + + flush_dcache_page(pg); +} + +void flush_icache_user_page(struct vm_area_struct *vma, struct page *page, + unsigned long addr, int len) +{ + void *maddr; + + maddr = kmap_local_page(page) + (addr & ~PAGE_MASK); + flush_icache_range((unsigned long)maddr, (unsigned long)maddr + len); + kunmap_local(maddr); +} -- cgit v1.2.3