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authorLennert Buytenhek <buytenh@wantstofly.org>2006-07-01 14:58:20 -0400
committerRussell King <rmk+kernel@arm.linux.org.uk>2006-07-01 14:58:20 -0400
commita069c896d0d6c028581089da7a9a9037a63c2803 (patch)
tree7b82eeab31974be5e5554f696dbf4351f678e680 /arch/arm/mm/ioremap.c
parentae95bfbb2b67eba5d67a0478a8715682a87e2616 (diff)
[ARM] 3705/1: add supersection support to ioremap()
Patch from Lennert Buytenhek Analogous to the previous patch that allows ioremap() to use section mappings, this patch allows ioremap() to use supersection mappings. Original patch by Deepak Saxena. Signed-off-by: Lennert Buytenhek <buytenh@wantstofly.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Diffstat (limited to 'arch/arm/mm/ioremap.c')
-rw-r--r--arch/arm/mm/ioremap.c66
1 files changed, 63 insertions, 3 deletions
diff --git a/arch/arm/mm/ioremap.c b/arch/arm/mm/ioremap.c
index 6aa13d59c85..7eac87f0518 100644
--- a/arch/arm/mm/ioremap.c
+++ b/arch/arm/mm/ioremap.c
@@ -33,8 +33,8 @@
33#include <asm/sizes.h> 33#include <asm/sizes.h>
34 34
35/* 35/*
36 * Used by ioremap() and iounmap() code to mark section-mapped I/O regions 36 * Used by ioremap() and iounmap() code to mark (super)section-mapped
37 * in vm_struct->flags field. 37 * I/O regions in vm_struct->flags field.
38 */ 38 */
39#define VM_ARM_SECTION_MAPPING 0x80000000 39#define VM_ARM_SECTION_MAPPING 0x80000000
40 40
@@ -233,6 +233,54 @@ remap_area_sections(unsigned long virt, unsigned long pfn,
233 233
234 return 0; 234 return 0;
235} 235}
236
237static int
238remap_area_supersections(unsigned long virt, unsigned long pfn,
239 unsigned long size, unsigned long flags)
240{
241 unsigned long prot, addr = virt, end = virt + size;
242 pgd_t *pgd;
243
244 /*
245 * Remove and free any PTE-based mapping, and
246 * sync the current kernel mapping.
247 */
248 unmap_area_sections(virt, size);
249
250 prot = PMD_TYPE_SECT | PMD_SECT_SUPER | PMD_SECT_AP_WRITE |
251 PMD_DOMAIN(DOMAIN_IO) |
252 (flags & (L_PTE_CACHEABLE | L_PTE_BUFFERABLE));
253
254 /*
255 * ARMv6 and above need XN set to prevent speculative prefetches
256 * hitting IO.
257 */
258 if (cpu_architecture() >= CPU_ARCH_ARMv6)
259 prot |= PMD_SECT_XN;
260
261 pgd = pgd_offset_k(virt);
262 do {
263 unsigned long super_pmd_val, i;
264
265 super_pmd_val = __pfn_to_phys(pfn) | prot;
266 super_pmd_val |= ((pfn >> (32 - PAGE_SHIFT)) & 0xf) << 20;
267
268 for (i = 0; i < 8; i++) {
269 pmd_t *pmd = pmd_offset(pgd, addr);
270
271 pmd[0] = __pmd(super_pmd_val);
272 pmd[1] = __pmd(super_pmd_val);
273 flush_pmd_entry(pmd);
274
275 addr += PGDIR_SIZE;
276 pgd++;
277 }
278
279 pfn += SUPERSECTION_SIZE >> PAGE_SHIFT;
280 } while (addr < end);
281
282 return 0;
283}
236#endif 284#endif
237 285
238 286
@@ -255,6 +303,13 @@ __ioremap_pfn(unsigned long pfn, unsigned long offset, size_t size,
255 int err; 303 int err;
256 unsigned long addr; 304 unsigned long addr;
257 struct vm_struct * area; 305 struct vm_struct * area;
306 unsigned int cr = get_cr();
307
308 /*
309 * High mappings must be supersection aligned
310 */
311 if (pfn >= 0x100000 && (__pfn_to_phys(pfn) & ~SUPERSECTION_MASK))
312 return NULL;
258 313
259 area = get_vm_area(size, VM_IOREMAP); 314 area = get_vm_area(size, VM_IOREMAP);
260 if (!area) 315 if (!area)
@@ -262,7 +317,12 @@ __ioremap_pfn(unsigned long pfn, unsigned long offset, size_t size,
262 addr = (unsigned long)area->addr; 317 addr = (unsigned long)area->addr;
263 318
264#ifndef CONFIG_SMP 319#ifndef CONFIG_SMP
265 if (!((__pfn_to_phys(pfn) | size | addr) & ~PMD_MASK)) { 320 if ((((cpu_architecture() >= CPU_ARCH_ARMv6) && (cr & CR_XP)) ||
321 cpu_is_xsc3()) &&
322 !((__pfn_to_phys(pfn) | size | addr) & ~SUPERSECTION_MASK)) {
323 area->flags |= VM_ARM_SECTION_MAPPING;
324 err = remap_area_supersections(addr, pfn, size, flags);
325 } else if (!((__pfn_to_phys(pfn) | size | addr) & ~PMD_MASK)) {
266 area->flags |= VM_ARM_SECTION_MAPPING; 326 area->flags |= VM_ARM_SECTION_MAPPING;
267 err = remap_area_sections(addr, pfn, size, flags); 327 err = remap_area_sections(addr, pfn, size, flags);
268 } else 328 } else