* Copyright (C) 2010 Michal Simek <monstr@monstr.eu>
* Copyright (C) 2010 PetaLogix
* Copyright (C) 2005 John Williams <jwilliams@itee.uq.edu.au>
- *
- * Based on PowerPC version derived from arch/arm/mm/consistent.c
- * Copyright (C) 2001 Dan Malek (dmalek@jlc.net)
- * Copyright (C) 2000 Russell King
*/
- #include <linux/export.h>
- #include <linux/signal.h>
- #include <linux/sched.h>
#include <linux/kernel.h>
- #include <linux/errno.h>
#include <linux/string.h>
#include <linux/types.h>
- #include <linux/ptrace.h>
- #include <linux/mman.h>
#include <linux/mm.h>
- #include <linux/swap.h>
- #include <linux/stddef.h>
- #include <linux/vmalloc.h>
#include <linux/init.h>
- #include <linux/delay.h>
- #include <linux/memblock.h>
- #include <linux/highmem.h>
- #include <linux/pci.h>
- #include <linux/interrupt.h>
- #include <linux/gfp.h>
#include <linux/dma-noncoherent.h>
-
- #include <asm/pgalloc.h>
- #include <linux/io.h>
- #include <linux/hardirq.h>
- #include <linux/mmu_context.h>
- #include <asm/mmu.h>
- #include <linux/uaccess.h>
- #include <asm/pgtable.h>
#include <asm/cpuinfo.h>
- #include <asm/tlbflush.h>
+ #include <asm/cacheflush.h>
- #ifndef CONFIG_MMU
- /* I have to use dcache values because I can't relate on ram size */
- # define UNCACHED_SHADOW_MASK (cpuinfo.dcache_high - cpuinfo.dcache_base + 1)
- #endif
-
- /*
- * Consistent memory allocators. Used for DMA devices that want to
- * share uncached memory with the processor core.
- * My crufty no-MMU approach is simple. In the HW platform we can optionally
- * mirror the DDR up above the processor cacheable region. So, memory accessed
- * in this mirror region will not be cached. It's alloced from the same
- * pool as normal memory, but the handle we return is shifted up into the
- * uncached region. This will no doubt cause big problems if memory allocated
- * here is not also freed properly. -- JW
- */
- void *arch_dma_alloc(struct device *dev, size_t size, dma_addr_t *dma_handle,
- gfp_t gfp, unsigned long attrs)
+ void arch_dma_prep_coherent(struct page *page, size_t size)
{
- unsigned long order, vaddr;
- void *ret;
- unsigned int i, err = 0;
- struct page *page, *end;
-
- #ifdef CONFIG_MMU
- phys_addr_t pa;
- struct vm_struct *area;
- unsigned long va;
- #endif
-
- if (in_interrupt())
- BUG();
-
- /* Only allocate page size areas. */
- size = PAGE_ALIGN(size);
- order = get_order(size);
-
- vaddr = __get_free_pages(gfp | __GFP_ZERO, order);
- if (!vaddr)
- return NULL;
+ phys_addr_t paddr = page_to_phys(page);
- /*
- * we need to ensure that there are no cachelines in use,
- * or worse dirty in this area.
- */
- flush_dcache_range(virt_to_phys((void *)vaddr),
- virt_to_phys((void *)vaddr) + size);
+ flush_dcache_range(paddr, paddr + size);
+ }
#ifndef CONFIG_MMU
- ret = (void *)vaddr;
- /*
- * Here's the magic! Note if the uncached shadow is not implemented,
- * it's up to the calling code to also test that condition and make
- * other arranegments, such as manually flushing the cache and so on.
- */
- # ifdef CONFIG_XILINX_UNCACHED_SHADOW
- ret = (void *)((unsigned) ret | UNCACHED_SHADOW_MASK);
- # endif
- if ((unsigned int)ret > cpuinfo.dcache_base &&
- (unsigned int)ret < cpuinfo.dcache_high)
- pr_warn("ERROR: Your cache coherent area is CACHED!!!\n");
-
- /* dma_handle is same as physical (shadowed) address */
- *dma_handle = (dma_addr_t)ret;
+ /*
+ * Consistent memory allocators. Used for DMA devices that want to share
+ * uncached memory with the processor core. My crufty no-MMU approach is
+ * simple. In the HW platform we can optionally mirror the DDR up above the
+ * processor cacheable region. So, memory accessed in this mirror region will
+ * not be cached. It's alloced from the same pool as normal memory, but the
+ * handle we return is shifted up into the uncached region. This will no doubt
+ * cause big problems if memory allocated here is not also freed properly. -- JW
+ *
+ * I have to use dcache values because I can't relate on ram size:
+ */
+ #ifdef CONFIG_XILINX_UNCACHED_SHADOW
+ #define UNCACHED_SHADOW_MASK (cpuinfo.dcache_high - cpuinfo.dcache_base + 1)
#else
- /* Allocate some common virtual space to map the new pages. */
- area = get_vm_area(size, VM_ALLOC);
- if (!area) {
- free_pages(vaddr, order);
- return NULL;
- }
- va = (unsigned long) area->addr;
- ret = (void *)va;
-
- /* This gives us the real physical address of the first page. */
- *dma_handle = pa = __virt_to_phys(vaddr);
- #endif
-
- /*
- * free wasted pages. We skip the first page since we know
- * that it will have count = 1 and won't require freeing.
- * We also mark the pages in use as reserved so that
- * remap_page_range works.
- */
- page = virt_to_page(vaddr);
- end = page + (1 << order);
-
- split_page(page, order);
-
- for (i = 0; i < size && err == 0; i += PAGE_SIZE) {
- #ifdef CONFIG_MMU
- /* MS: This is the whole magic - use cache inhibit pages */
- err = map_page(va + i, pa + i, _PAGE_KERNEL | _PAGE_NO_CACHE);
- #endif
+ #define UNCACHED_SHADOW_MASK 0
+ #endif /* CONFIG_XILINX_UNCACHED_SHADOW */
- SetPageReserved(page);
- page++;
- }
-
- /* Free the otherwise unused pages. */
- while (page < end) {
- __free_page(page);
- page++;
- }
-
- if (err) {
- free_pages(vaddr, order);
- return NULL;
- }
-
- return ret;
- }
-
- #ifdef CONFIG_MMU
- static pte_t *consistent_virt_to_pte(void *vaddr)
+ void *uncached_kernel_address(void *ptr)
{
- unsigned long addr = (unsigned long)vaddr;
-
- return pte_offset_kernel(pmd_offset(pgd_offset_k(addr), addr), addr);
- }
-
- long arch_dma_coherent_to_pfn(struct device *dev, void *vaddr,
- dma_addr_t dma_addr)
- {
- pte_t *ptep = consistent_virt_to_pte(vaddr);
-
- if (pte_none(*ptep) || !pte_present(*ptep))
- return 0;
+ unsigned long addr = (unsigned long)ptr;
- return pte_pfn(*ptep);
+ addr |= UNCACHED_SHADOW_MASK;
+ if (addr > cpuinfo.dcache_base && addr < cpuinfo.dcache_high)
+ pr_warn("ERROR: Your cache coherent area is CACHED!!!\n");
+ return (void *)addr;
}
- #endif
- /*
- * free page(s) as defined by the above mapping.
- */
- void arch_dma_free(struct device *dev, size_t size, void *vaddr,
- dma_addr_t dma_addr, unsigned long attrs)
+ void *cached_kernel_address(void *ptr)
{
- struct page *page;
-
- if (in_interrupt())
- BUG();
-
- size = PAGE_ALIGN(size);
-
- #ifndef CONFIG_MMU
- /* Clear SHADOW_MASK bit in address, and free as per usual */
- # ifdef CONFIG_XILINX_UNCACHED_SHADOW
- vaddr = (void *)((unsigned)vaddr & ~UNCACHED_SHADOW_MASK);
- # endif
- page = virt_to_page(vaddr);
-
- do {
- __free_reserved_page(page);
- page++;
- } while (size -= PAGE_SIZE);
- #else
- do {
- pte_t *ptep = consistent_virt_to_pte(vaddr);
- unsigned long pfn;
-
- if (!pte_none(*ptep) && pte_present(*ptep)) {
- pfn = pte_pfn(*ptep);
- pte_clear(&init_mm, (unsigned int)vaddr, ptep);
- if (pfn_valid(pfn)) {
- page = pfn_to_page(pfn);
- __free_reserved_page(page);
- }
- }
- vaddr += PAGE_SIZE;
- } while (size -= PAGE_SIZE);
+ unsigned long addr = (unsigned long)ptr;
- /* flush tlb */
- flush_tlb_all();
- #endif
+ return (void *)(addr & ~UNCACHED_SHADOW_MASK);
}
-#else /* CONFIG_MMU */
-static int __init atomic_pool_init(void)
-{
- return dma_atomic_pool_init(GFP_KERNEL, pgprot_noncached(PAGE_KERNEL));
-}
-postcore_initcall(atomic_pool_init);
+ #endif /* CONFIG_MMU */
projects / platform / kernel / linux-rpi.git / commitdiff