[PATCH] ppc64: Fix semantics of __ioremap

This patch fixes ppc64 __ioremap() so that it stops adding implicitely
_PAGE_GUARDED when the cache is not writeback, and instead, let the callers
provide the flag they want here.  This allows things like framebuffers to
explicitely request a non-cacheable and non-guarded mapping which is more
efficient for that type of memory without side effects.  The patch also
fixes all current callers to add _PAGE_GUARDED except btext, which is fine
without it.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
Benjamin Herrenschmidt 2005-04-16 15:24:33 -07:00 committed by Linus Torvalds
parent 7bbd827750
commit dfbacdc1a0
4 changed files with 18 additions and 16 deletions

View File

@ -142,7 +142,7 @@ static void __init maple_init_early(void)
if (physport) {
void *comport;
/* Map the uart for udbg. */
comport = (void *)__ioremap(physport, 16, _PAGE_NO_CACHE);
comport = (void *)ioremap(physport, 16);
udbg_init_uart(comport, default_speed);
ppc_md.udbg_putc = udbg_putc;

View File

@ -363,7 +363,7 @@ static void __init pSeries_init_early(void)
find_udbg_vterm();
else if (physport) {
/* Map the uart for udbg. */
comport = (void *)__ioremap(physport, 16, _PAGE_NO_CACHE);
comport = (void *)ioremap(physport, 16);
udbg_init_uart(comport, default_speed);
ppc_md.udbg_putc = udbg_putc;

View File

@ -547,8 +547,9 @@ static void __devinit pci_process_ISA_OF_ranges(struct device_node *isa_node,
if (range == NULL || (rlen < sizeof(struct isa_range))) {
printk(KERN_ERR "no ISA ranges or unexpected isa range size,"
"mapping 64k\n");
__ioremap_explicit(phb_io_base_phys, (unsigned long)phb_io_base_virt,
0x10000, _PAGE_NO_CACHE);
__ioremap_explicit(phb_io_base_phys,
(unsigned long)phb_io_base_virt,
0x10000, _PAGE_NO_CACHE | _PAGE_GUARDED);
return;
}
@ -576,7 +577,7 @@ static void __devinit pci_process_ISA_OF_ranges(struct device_node *isa_node,
__ioremap_explicit(phb_io_base_phys,
(unsigned long) phb_io_base_virt,
size, _PAGE_NO_CACHE);
size, _PAGE_NO_CACHE | _PAGE_GUARDED);
}
}
@ -692,7 +693,7 @@ void __devinit pci_setup_phb_io_dynamic(struct pci_controller *hose,
struct resource *res;
hose->io_base_virt = __ioremap(hose->io_base_phys, size,
_PAGE_NO_CACHE);
_PAGE_NO_CACHE | _PAGE_GUARDED);
DBG("phb%d io_base_phys 0x%lx io_base_virt 0x%lx\n",
hose->global_number, hose->io_base_phys,
(unsigned long) hose->io_base_virt);
@ -780,7 +781,8 @@ int remap_bus_range(struct pci_bus *bus)
if (get_bus_io_range(bus, &start_phys, &start_virt, &size))
return 1;
printk("mapping IO %lx -> %lx, size: %lx\n", start_phys, start_virt, size);
if (__ioremap_explicit(start_phys, start_virt, size, _PAGE_NO_CACHE))
if (__ioremap_explicit(start_phys, start_virt, size,
_PAGE_NO_CACHE | _PAGE_GUARDED))
return 1;
return 0;

View File

@ -155,7 +155,8 @@ static void map_io_page(unsigned long ea, unsigned long pa, int flags)
ptep = pte_alloc_kernel(&ioremap_mm, pmdp, ea);
pa = abs_to_phys(pa);
set_pte_at(&ioremap_mm, ea, ptep, pfn_pte(pa >> PAGE_SHIFT, __pgprot(flags)));
set_pte_at(&ioremap_mm, ea, ptep, pfn_pte(pa >> PAGE_SHIFT,
__pgprot(flags)));
spin_unlock(&ioremap_mm.page_table_lock);
} else {
unsigned long va, vpn, hash, hpteg;
@ -191,12 +192,9 @@ static void __iomem * __ioremap_com(unsigned long addr, unsigned long pa,
if ((flags & _PAGE_PRESENT) == 0)
flags |= pgprot_val(PAGE_KERNEL);
if (flags & (_PAGE_NO_CACHE | _PAGE_WRITETHRU))
flags |= _PAGE_GUARDED;
for (i = 0; i < size; i += PAGE_SIZE) {
for (i = 0; i < size; i += PAGE_SIZE)
map_io_page(ea+i, pa+i, flags);
}
return (void __iomem *) (ea + (addr & ~PAGE_MASK));
}
@ -205,7 +203,7 @@ static void __iomem * __ioremap_com(unsigned long addr, unsigned long pa,
void __iomem *
ioremap(unsigned long addr, unsigned long size)
{
return __ioremap(addr, size, _PAGE_NO_CACHE);
return __ioremap(addr, size, _PAGE_NO_CACHE | _PAGE_GUARDED);
}
void __iomem *
@ -272,7 +270,8 @@ int __ioremap_explicit(unsigned long pa, unsigned long ea,
return 1;
}
if (ea != (unsigned long) area->addr) {
printk(KERN_ERR "unexpected addr return from im_get_area\n");
printk(KERN_ERR "unexpected addr return from "
"im_get_area\n");
return 1;
}
}
@ -315,7 +314,8 @@ static void unmap_im_area_pte(pmd_t *pmd, unsigned long address,
continue;
if (pte_present(page))
continue;
printk(KERN_CRIT "Whee.. Swapped out page in kernel page table\n");
printk(KERN_CRIT "Whee.. Swapped out page in kernel page"
" table\n");
} while (address < end);
}
@ -352,7 +352,7 @@ static void unmap_im_area_pmd(pgd_t *dir, unsigned long address,
* Access to IO memory should be serialized by driver.
* This code is modeled after vmalloc code - unmap_vm_area()
*
* XXX what about calls before mem_init_done (ie python_countermeasures())
* XXX what about calls before mem_init_done (ie python_countermeasures())
*/
void iounmap(volatile void __iomem *token)
{