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>
diff --git a/arch/sh/drivers/pci/pci.c b/arch/sh/drivers/pci/pci.c
index 7377a8a..d439336 100644
--- a/arch/sh/drivers/pci/pci.c
+++ b/arch/sh/drivers/pci/pci.c
@@ -195,7 +195,7 @@
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 @@
* 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;
}
diff --git a/arch/sh/mm/ioremap.c b/arch/sh/mm/ioremap.c
index 96fa4a9..a9fe80c 100644
--- a/arch/sh/mm/ioremap.c
+++ b/arch/sh/mm/ioremap.c
@@ -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>
@@ -135,6 +136,20 @@
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..
*/
if (phys_addr < virt_to_phys(high_memory))
@@ -192,7 +207,7 @@
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