sh: Inhibit mapping PCI apertures through page tables.

Inhibit mapping through page tables in __ioremap() for PCI memory
apertures on SH7751 and SH7780-style PCI controllers, translation is
not possible for these areas. For other users that map a small window
in P1/P2 space, ioremap() traps that already, and should never make
it to __ioremap().

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This commit is contained in:
Paul Mundt 2006-09-27 16:45:22 +09:00
parent 959f85f8a3
commit a3e61d50dc
2 changed files with 25 additions and 12 deletions

View File

@ -195,7 +195,7 @@ void __iomem *pci_iomap(struct pci_dev *dev, int bar, unsigned long maxlen)
unsigned long len = pci_resource_len(dev, bar);
unsigned long flags = pci_resource_flags(dev, bar);
if (!len || !start)
if (unlikely(!len || !start))
return NULL;
if (maxlen && len > maxlen)
len = maxlen;
@ -204,18 +204,16 @@ void __iomem *pci_iomap(struct pci_dev *dev, int bar, unsigned long maxlen)
* Presently the IORESOURCE_MEM case is a bit special, most
* SH7751 style PCI controllers have PCI memory at a fixed
* location in the address space where no remapping is desired
* (traditionally at 0xfd000000). Once this changes, the
* IORESOURCE_MEM case will have to switch to using ioremap() and
* more care will have to be taken to inhibit page table mapping
* for legacy cores.
*
* For now everything wraps to ioport_map(), since boards that
* have PCI will be able to check the address range properly on
* their own.
* -- PFM.
* (typically at 0xfd000000, but is_pci_memaddr() will know
* best). With the IORESOURCE_MEM case more care has to be taken
* to inhibit page table mapping for legacy cores, but this is
* punted off to __ioremap().
* -- PFM.
*/
if (flags & (IORESOURCE_IO | IORESOURCE_MEM))
if (flags & IORESOURCE_IO)
return ioport_map(start, len);
if (flags & IORESOURCE_MEM)
return ioremap(start, len);
return NULL;
}

View File

@ -15,6 +15,7 @@
#include <linux/vmalloc.h>
#include <linux/module.h>
#include <linux/mm.h>
#include <linux/pci.h>
#include <asm/io.h>
#include <asm/page.h>
#include <asm/pgalloc.h>
@ -134,6 +135,20 @@ void __iomem *__ioremap(unsigned long phys_addr, unsigned long size,
if (phys_addr >= 0xA0000 && last_addr < 0x100000)
return (void __iomem *)phys_to_virt(phys_addr);
/*
* If we're on an SH7751 or SH7780 PCI controller, PCI memory is
* mapped at the end of the address space (typically 0xfd000000)
* in a non-translatable area, so mapping through page tables for
* this area is not only pointless, but also fundamentally
* broken. Just return the physical address instead.
*
* For boards that map a small PCI memory aperture somewhere in
* P1/P2 space, ioremap() will already do the right thing,
* and we'll never get this far.
*/
if (is_pci_memaddr(phys_addr) && is_pci_memaddr(last_addr))
return (void __iomem *)phys_addr;
/*
* Don't allow anybody to remap normal RAM that we're using..
*/
@ -192,7 +207,7 @@ void __iounmap(void __iomem *addr)
unsigned long vaddr = (unsigned long __force)addr;
struct vm_struct *p;
if (PXSEG(vaddr) < P3SEG)
if (PXSEG(vaddr) < P3SEG || is_pci_memaddr(vaddr))
return;
#ifdef CONFIG_32BIT