4.4-stable review patch. If anyone has any objections, please let me know.
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From: Paul Burton paul.burton@mips.com
[ Upstream commit 0494d7ffdcebc6935410ea0719b24ab626675351 ]
isa_virt_to_bus() & isa_bus_to_virt() claim to treat ISA bus addresses as being identical to physical addresses, but they fail to do so in the presence of a non-zero PHYS_OFFSET.
Correct this by having them use virt_to_phys() & phys_to_virt(), which consolidates the calculations to one place & ensures that ISA bus addresses do indeed match physical addresses.
Signed-off-by: Paul Burton paul.burton@mips.com Patchwork: https://patchwork.linux-mips.org/patch/20047/ Cc: James Hogan jhogan@kernel.org Cc: Ralf Baechle ralf@linux-mips.org Cc: linux-mips@linux-mips.org Cc: Vladimir Kondratiev vladimir.kondratiev@intel.com Signed-off-by: Sasha Levin alexander.levin@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- arch/mips/include/asm/io.h | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-)
--- a/arch/mips/include/asm/io.h +++ b/arch/mips/include/asm/io.h @@ -141,14 +141,14 @@ static inline void * phys_to_virt(unsign /* * ISA I/O bus memory addresses are 1:1 with the physical address. */ -static inline unsigned long isa_virt_to_bus(volatile void * address) +static inline unsigned long isa_virt_to_bus(volatile void *address) { - return (unsigned long)address - PAGE_OFFSET; + return virt_to_phys(address); }
-static inline void * isa_bus_to_virt(unsigned long address) +static inline void *isa_bus_to_virt(unsigned long address) { - return (void *)(address + PAGE_OFFSET); + return phys_to_virt(address); }
#define isa_page_to_bus page_to_phys