Commit dfbacdc1 authored by Benjamin Herrenschmidt's avatar Benjamin Herrenschmidt Committed by Linus Torvalds
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[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: default avatarBenjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent 7bbd8277

arch/ppc64/kernel/maple_setup.c

+1 −1
Original line number Diff line number Diff line
@@ -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;

arch/ppc64/kernel/pSeries_setup.c

+1 −1
Original line number Diff line number Diff line
@@ -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;

arch/ppc64/kernel/pci.c

+7 −5
Original line number Diff line number Diff line
@@ -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;

arch/ppc64/mm/init.c

+9 −9
Original line number Diff line number Diff line
@@ -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);

}