parisc: Use lpa instruction to load physical addresses in driver code

Most I/O in the kernel is done using the kernel offset mapping.
However, there is one API that uses aliased kernel address ranges:

> The final category of APIs is for I/O to deliberately aliased address
> ranges inside the kernel.  Such aliases are set up by use of the
> vmap/vmalloc API.  Since kernel I/O goes via physical pages, the I/O
> subsystem assumes that the user mapping and kernel offset mapping are
> the only aliases.  This isn't true for vmap aliases, so anything in
> the kernel trying to do I/O to vmap areas must manually manage
> coherency.  It must do this by flushing the vmap range before doing
> I/O and invalidating it after the I/O returns.

For this reason, we should use the hardware lpa instruction to load the
physical address of kernel virtual addresses in the driver code.

I believe we only use the vmap/vmalloc API with old PA 1.x processors
which don't have a sba, so we don't hit this problem.

Tested on c3750, c8000 and rp3440.

Signed-off-by: John David Anglin <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>

1 files changed, 1 insertions, 1 deletions

diff --git a/drivers/parisc/ccio-dma.c b/drivers/parisc/ccio-dma.c
index 9b434644524c..8362517b98f9 100644
--- a/drivers/parisc/ccio-dma.c
+++ b/drivers/parisc/ccio-dma.c
@@ -570,7 +570,7 @@ ccio_io_pdir_entry(u64 *pdir_ptr, space_t sid, unsigned long vba,
 	** "hints" parm includes the VALID bit!
 	** "dep" clobbers the physical address offset bits as well.
 	*/
-	pa = virt_to_phys(vba);
+	pa = lpa(vba);
 	asm volatile("depw  %1,31,12,%0" : "+r" (pa) : "r" (hints));
 	((u32 *)pdir_ptr)[1] = (u32) pa;