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-rw-r--r--arch/tile/lib/memcpy_tile64.c280
1 files changed, 0 insertions, 280 deletions
diff --git a/arch/tile/lib/memcpy_tile64.c b/arch/tile/lib/memcpy_tile64.c
deleted file mode 100644
index 0290c222847b..000000000000
--- a/arch/tile/lib/memcpy_tile64.c
+++ /dev/null
@@ -1,280 +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 = smp_processor_id();
-
- /*
- * 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);
-}
-
-/*
- * 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)
-{
- int cpu = get_cpu();
- unsigned long retval;
-
- /*
- * 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) == cpu)
- 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;
- }
-
- retval = func(dest, source, len);
- put_cpu();
- return retval;
-}
-
-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() */