diff options
Diffstat (limited to 'arch/tile/lib/memcpy_tile64.c')
| -rw-r--r-- | arch/tile/lib/memcpy_tile64.c | 276 |
1 files changed, 0 insertions, 276 deletions
diff --git a/arch/tile/lib/memcpy_tile64.c b/arch/tile/lib/memcpy_tile64.c deleted file mode 100644 index 3bc4b4e40d93..000000000000 --- a/arch/tile/lib/memcpy_tile64.c +++ /dev/null @@ -1,276 +0,0 @@ -/* - * Copyright 2010 Tilera Corporation. All Rights Reserved. - * - * 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, version 2. - * - * This program is distributed in the hope that it will be useful, but - * WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or - * NON INFRINGEMENT. See the GNU General Public License for - * more details. - */ - -#include <linux/string.h> -#include <linux/smp.h> -#include <linux/module.h> -#include <linux/uaccess.h> -#include <asm/fixmap.h> -#include <asm/kmap_types.h> -#include <asm/tlbflush.h> -#include <hv/hypervisor.h> -#include <arch/chip.h> - - -#if !CHIP_HAS_COHERENT_LOCAL_CACHE() - -/* Defined in memcpy.S */ -extern unsigned long __memcpy_asm(void *to, const void *from, unsigned long n); -extern unsigned long __copy_to_user_inatomic_asm( - void __user *to, const void *from, unsigned long n); -extern unsigned long __copy_from_user_inatomic_asm( - void *to, const void __user *from, unsigned long n); -extern unsigned long __copy_from_user_zeroing_asm( - void *to, const void __user *from, unsigned long n); - -typedef unsigned long (*memcpy_t)(void *, const void *, unsigned long); - -/* Size above which to consider TLB games for performance */ -#define LARGE_COPY_CUTOFF 2048 - -/* Communicate to the simulator what we are trying to do. */ -#define sim_allow_multiple_caching(b) \ - __insn_mtspr(SPR_SIM_CONTROL, \ - SIM_CONTROL_ALLOW_MULTIPLE_CACHING | ((b) << _SIM_CONTROL_OPERATOR_BITS)) - -/* - * Copy memory by briefly enabling incoherent cacheline-at-a-time mode. - * - * We set up our own source and destination PTEs that we fully control. - * This is the only way to guarantee that we don't race with another - * thread that is modifying the PTE; we can't afford to try the - * copy_{to,from}_user() technique of catching the interrupt, since - * we must run with interrupts disabled to avoid the risk of some - * other code seeing the incoherent data in our cache. (Recall that - * our cache is indexed by PA, so even if the other code doesn't use - * our kmap_atomic virtual addresses, they'll still hit in cache using - * the normal VAs that aren't supposed to hit in cache.) - */ -static void memcpy_multicache(void *dest, const void *source, - pte_t dst_pte, pte_t src_pte, int len) -{ - int idx; - unsigned long flags, newsrc, newdst; - pmd_t *pmdp; - pte_t *ptep; - int type0, type1; - int cpu = get_cpu(); - - /* - * Disable interrupts so that we don't recurse into memcpy() - * in an interrupt handler, nor accidentally reference - * the PA of the source from an interrupt routine. Also - * notify the simulator that we're playing games so we don't - * generate spurious coherency warnings. - */ - local_irq_save(flags); - sim_allow_multiple_caching(1); - - /* Set up the new dest mapping */ - type0 = kmap_atomic_idx_push(); - idx = FIX_KMAP_BEGIN + (KM_TYPE_NR * cpu) + type0; - newdst = __fix_to_virt(idx) + ((unsigned long)dest & (PAGE_SIZE-1)); - pmdp = pmd_offset(pud_offset(pgd_offset_k(newdst), newdst), newdst); - ptep = pte_offset_kernel(pmdp, newdst); - if (pte_val(*ptep) != pte_val(dst_pte)) { - set_pte(ptep, dst_pte); - local_flush_tlb_page(NULL, newdst, PAGE_SIZE); - } - - /* Set up the new source mapping */ - type1 = kmap_atomic_idx_push(); - idx += (type0 - type1); - src_pte = hv_pte_set_nc(src_pte); - src_pte = hv_pte_clear_writable(src_pte); /* be paranoid */ - newsrc = __fix_to_virt(idx) + ((unsigned long)source & (PAGE_SIZE-1)); - pmdp = pmd_offset(pud_offset(pgd_offset_k(newsrc), newsrc), newsrc); - ptep = pte_offset_kernel(pmdp, newsrc); - __set_pte(ptep, src_pte); /* set_pte() would be confused by this */ - local_flush_tlb_page(NULL, newsrc, PAGE_SIZE); - - /* Actually move the data. */ - __memcpy_asm((void *)newdst, (const void *)newsrc, len); - - /* - * Remap the source as locally-cached and not OLOC'ed so that - * we can inval without also invaling the remote cpu's cache. - * This also avoids known errata with inv'ing cacheable oloc data. - */ - src_pte = hv_pte_set_mode(src_pte, HV_PTE_MODE_CACHE_NO_L3); - src_pte = hv_pte_set_writable(src_pte); /* need write access for inv */ - __set_pte(ptep, src_pte); /* set_pte() would be confused by this */ - local_flush_tlb_page(NULL, newsrc, PAGE_SIZE); - - /* - * Do the actual invalidation, covering the full L2 cache line - * at the end since __memcpy_asm() is somewhat aggressive. - */ - __inv_buffer((void *)newsrc, len); - - /* - * We're done: notify the simulator that all is back to normal, - * and re-enable interrupts and pre-emption. - */ - kmap_atomic_idx_pop(); - kmap_atomic_idx_pop(); - sim_allow_multiple_caching(0); - local_irq_restore(flags); - put_cpu(); -} - -/* - * Identify large copies from remotely-cached memory, and copy them - * via memcpy_multicache() if they look good, otherwise fall back - * to the particular kind of copying passed as the memcpy_t function. - */ -static unsigned long fast_copy(void *dest, const void *source, int len, - memcpy_t func) -{ - /* - * Check if it's big enough to bother with. We may end up doing a - * small copy via TLB manipulation if we're near a page boundary, - * but presumably we'll make it up when we hit the second page. - */ - while (len >= LARGE_COPY_CUTOFF) { - int copy_size, bytes_left_on_page; - pte_t *src_ptep, *dst_ptep; - pte_t src_pte, dst_pte; - struct page *src_page, *dst_page; - - /* Is the source page oloc'ed to a remote cpu? */ -retry_source: - src_ptep = virt_to_pte(current->mm, (unsigned long)source); - if (src_ptep == NULL) - break; - src_pte = *src_ptep; - if (!hv_pte_get_present(src_pte) || - !hv_pte_get_readable(src_pte) || - hv_pte_get_mode(src_pte) != HV_PTE_MODE_CACHE_TILE_L3) - break; - if (get_remote_cache_cpu(src_pte) == smp_processor_id()) - break; - src_page = pfn_to_page(pte_pfn(src_pte)); - get_page(src_page); - if (pte_val(src_pte) != pte_val(*src_ptep)) { - put_page(src_page); - goto retry_source; - } - if (pte_huge(src_pte)) { - /* Adjust the PTE to correspond to a small page */ - int pfn = pte_pfn(src_pte); - pfn += (((unsigned long)source & (HPAGE_SIZE-1)) - >> PAGE_SHIFT); - src_pte = pfn_pte(pfn, src_pte); - src_pte = pte_mksmall(src_pte); - } - - /* Is the destination page writable? */ -retry_dest: - dst_ptep = virt_to_pte(current->mm, (unsigned long)dest); - if (dst_ptep == NULL) { - put_page(src_page); - break; - } - dst_pte = *dst_ptep; - if (!hv_pte_get_present(dst_pte) || - !hv_pte_get_writable(dst_pte)) { - put_page(src_page); - break; - } - dst_page = pfn_to_page(pte_pfn(dst_pte)); - if (dst_page == src_page) { - /* - * Source and dest are on the same page; this - * potentially exposes us to incoherence if any - * part of src and dest overlap on a cache line. - * Just give up rather than trying to be precise. - */ - put_page(src_page); - break; - } - get_page(dst_page); - if (pte_val(dst_pte) != pte_val(*dst_ptep)) { - put_page(dst_page); - goto retry_dest; - } - if (pte_huge(dst_pte)) { - /* Adjust the PTE to correspond to a small page */ - int pfn = pte_pfn(dst_pte); - pfn += (((unsigned long)dest & (HPAGE_SIZE-1)) - >> PAGE_SHIFT); - dst_pte = pfn_pte(pfn, dst_pte); - dst_pte = pte_mksmall(dst_pte); - } - - /* All looks good: create a cachable PTE and copy from it */ - copy_size = len; - bytes_left_on_page = - PAGE_SIZE - (((int)source) & (PAGE_SIZE-1)); - if (copy_size > bytes_left_on_page) - copy_size = bytes_left_on_page; - bytes_left_on_page = - PAGE_SIZE - (((int)dest) & (PAGE_SIZE-1)); - if (copy_size > bytes_left_on_page) - copy_size = bytes_left_on_page; - memcpy_multicache(dest, source, dst_pte, src_pte, copy_size); - - /* Release the pages */ - put_page(dst_page); - put_page(src_page); - - /* Continue on the next page */ - dest += copy_size; - source += copy_size; - len -= copy_size; - } - - return func(dest, source, len); -} - -void *memcpy(void *to, const void *from, __kernel_size_t n) -{ - if (n < LARGE_COPY_CUTOFF) - return (void *)__memcpy_asm(to, from, n); - else - return (void *)fast_copy(to, from, n, __memcpy_asm); -} - -unsigned long __copy_to_user_inatomic(void __user *to, const void *from, - unsigned long n) -{ - if (n < LARGE_COPY_CUTOFF) - return __copy_to_user_inatomic_asm(to, from, n); - else - return fast_copy(to, from, n, __copy_to_user_inatomic_asm); -} - -unsigned long __copy_from_user_inatomic(void *to, const void __user *from, - unsigned long n) -{ - if (n < LARGE_COPY_CUTOFF) - return __copy_from_user_inatomic_asm(to, from, n); - else - return fast_copy(to, from, n, __copy_from_user_inatomic_asm); -} - -unsigned long __copy_from_user_zeroing(void *to, const void __user *from, - unsigned long n) -{ - if (n < LARGE_COPY_CUTOFF) - return __copy_from_user_zeroing_asm(to, from, n); - else - return fast_copy(to, from, n, __copy_from_user_zeroing_asm); -} - -#endif /* !CHIP_HAS_COHERENT_LOCAL_CACHE() */ |
