case _PAGE_CACHE_MODE_WC:
err = _set_memory_wc(vaddr, nrpages);
break;
+ case _PAGE_CACHE_MODE_WT:
+ err = _set_memory_wt(vaddr, nrpages);
+ break;
case _PAGE_CACHE_MODE_WB:
err = _set_memory_wb(vaddr, nrpages);
break;
!PageReserved(pfn_to_page(start_pfn + i)))
return 1;
- WARN_ONCE(1, "ioremap on RAM pfn 0x%lx\n", start_pfn);
-
return 0;
}
pgprot_t prot;
int retval;
void __iomem *ret_addr;
- int ram_region;
/* Don't allow wraparound or zero size */
last_addr = phys_addr + size - 1;
/*
* Don't allow anybody to remap normal RAM that we're using..
*/
- /* First check if whole region can be identified as RAM or not */
- ram_region = region_is_ram(phys_addr, size);
- if (ram_region > 0) {
- WARN_ONCE(1, "ioremap on RAM at 0x%lx - 0x%lx\n",
- (unsigned long int)phys_addr,
- (unsigned long int)last_addr);
+ pfn = phys_addr >> PAGE_SHIFT;
+ last_pfn = last_addr >> PAGE_SHIFT;
+ if (walk_system_ram_range(pfn, last_pfn - pfn + 1, NULL,
+ __ioremap_check_ram) == 1) {
+ WARN_ONCE(1, "ioremap on RAM at %pa - %pa\n",
+ &phys_addr, &last_addr);
return NULL;
}
- /* If could not be identified(-1), check page by page */
- if (ram_region < 0) {
- pfn = phys_addr >> PAGE_SHIFT;
- last_pfn = last_addr >> PAGE_SHIFT;
- if (walk_system_ram_range(pfn, last_pfn - pfn + 1, NULL,
- __ioremap_check_ram) == 1)
- return NULL;
- }
/*
* Mappings have to be page-aligned
*/
prot = __pgprot(pgprot_val(prot) |
cachemode2protval(_PAGE_CACHE_MODE_WC));
break;
+ case _PAGE_CACHE_MODE_WT:
+ prot = __pgprot(pgprot_val(prot) |
+ cachemode2protval(_PAGE_CACHE_MODE_WT));
+ break;
case _PAGE_CACHE_MODE_WB:
break;
}
{
/*
* Ideally, this should be:
- * pat_enabled ? _PAGE_CACHE_MODE_UC : _PAGE_CACHE_MODE_UC_MINUS;
+ * pat_enabled() ? _PAGE_CACHE_MODE_UC : _PAGE_CACHE_MODE_UC_MINUS;
*
* Till we fix all X drivers to use ioremap_wc(), we will use
- * UC MINUS.
+ * UC MINUS. Drivers that are certain they need or can already
+ * be converted over to strong UC can use ioremap_uc().
*/
enum page_cache_mode pcm = _PAGE_CACHE_MODE_UC_MINUS;
}
EXPORT_SYMBOL(ioremap_nocache);
+/**
+ * ioremap_uc - map bus memory into CPU space as strongly uncachable
+ * @phys_addr: bus address of the memory
+ * @size: size of the resource to map
+ *
+ * ioremap_uc performs a platform specific sequence of operations to
+ * make bus memory CPU accessible via the readb/readw/readl/writeb/
+ * writew/writel functions and the other mmio helpers. The returned
+ * address is not guaranteed to be usable directly as a virtual
+ * address.
+ *
+ * This version of ioremap ensures that the memory is marked with a strong
+ * preference as completely uncachable on the CPU when possible. For non-PAT
+ * systems this ends up setting page-attribute flags PCD=1, PWT=1. For PAT
+ * systems this will set the PAT entry for the pages as strong UC. This call
+ * will honor existing caching rules from things like the PCI bus. Note that
+ * there are other caches and buffers on many busses. In particular driver
+ * authors should read up on PCI writes.
+ *
+ * It's useful if some control registers are in such an area and
+ * write combining or read caching is not desirable:
+ *
+ * Must be freed with iounmap.
+ */
+void __iomem *ioremap_uc(resource_size_t phys_addr, unsigned long size)
+{
+ enum page_cache_mode pcm = _PAGE_CACHE_MODE_UC;
+
+ return __ioremap_caller(phys_addr, size, pcm,
+ __builtin_return_address(0));
+}
+EXPORT_SYMBOL_GPL(ioremap_uc);
+
/**
* ioremap_wc - map memory into CPU space write combined
* @phys_addr: bus address of the memory
*/
void __iomem *ioremap_wc(resource_size_t phys_addr, unsigned long size)
{
- if (pat_enabled)
- return __ioremap_caller(phys_addr, size, _PAGE_CACHE_MODE_WC,
+ return __ioremap_caller(phys_addr, size, _PAGE_CACHE_MODE_WC,
__builtin_return_address(0));
- else
- return ioremap_nocache(phys_addr, size);
}
EXPORT_SYMBOL(ioremap_wc);
+/**
+ * ioremap_wt - map memory into CPU space write through
+ * @phys_addr: bus address of the memory
+ * @size: size of the resource to map
+ *
+ * This version of ioremap ensures that the memory is marked write through.
+ * Write through stores data into memory while keeping the cache up-to-date.
+ *
+ * Must be freed with iounmap.
+ */
+void __iomem *ioremap_wt(resource_size_t phys_addr, unsigned long size)
+{
+ return __ioremap_caller(phys_addr, size, _PAGE_CACHE_MODE_WT,
+ __builtin_return_address(0));
+}
+EXPORT_SYMBOL(ioremap_wt);
+
void __iomem *ioremap_cache(resource_size_t phys_addr, unsigned long size)
{
return __ioremap_caller(phys_addr, size, _PAGE_CACHE_MODE_WB,
}
EXPORT_SYMBOL(iounmap);
-int arch_ioremap_pud_supported(void)
+int __init arch_ioremap_pud_supported(void)
{
#ifdef CONFIG_X86_64
return cpu_has_gbpages;
#endif
}
-int arch_ioremap_pmd_supported(void)
+int __init arch_ioremap_pmd_supported(void)
{
return cpu_has_pse;
}
{
unsigned long start = phys & PAGE_MASK;
unsigned long offset = phys & ~PAGE_MASK;
- unsigned long vaddr;
+ void *vaddr;
/* If page is RAM, we can use __va. Otherwise ioremap and unmap. */
if (page_is_ram(start >> PAGE_SHIFT))
return __va(phys);
- vaddr = (unsigned long)ioremap_cache(start, PAGE_SIZE);
+ vaddr = ioremap_cache(start, PAGE_SIZE);
/* Only add the offset on success and return NULL if the ioremap() failed: */
if (vaddr)
vaddr += offset;
- return (void *)vaddr;
+ return vaddr;
}
void unxlate_dev_mem_ptr(phys_addr_t phys, void *addr)
return;
iounmap((void __iomem *)((unsigned long)addr & PAGE_MASK));
- return;
}
static pte_t bm_pte[PAGE_SIZE/sizeof(pte_t)] __page_aligned_bss;