On Thu, Nov 30, 2017 at 03:09:33PM -0800, David Daney wrote:

On 11/30/2017 02:56 PM, James Hogan wrote:

quoted

On Thu, Nov 30, 2017 at 01:49:43PM -0800, David Daney wrote:

quoted

On 11/30/2017 01:36 PM, James Hogan wrote:

quoted

On Tue, Nov 28, 2017 at 04:55:34PM -0800, David Daney wrote:

quoted

Signed-off-by: Carlos Munoz <cmunoz-YGCgFSpz5w/QT0dZR+AlfA@public.gmane.org>
Signed-off-by: Steven J. Hill <Steven.Hill-YGCgFSpz5w/QT0dZR+AlfA@public.gmane.org>
Signed-off-by: David Daney <david.daney-YGCgFSpz5w/QT0dZR+AlfA@public.gmane.org>
---
   arch/mips/cavium-octeon/setup.c       |  6 ++++++
   arch/mips/include/asm/octeon/octeon.h | 12 ++++++++++--
   2 files changed, 16 insertions(+), 2 deletions(-)

diff --git a/arch/mips/cavium-octeon/setup.c b/arch/mips/cavium-octeon/setup.c
index a8034d0dcade..99e6a68bc652 100644
--- a/arch/mips/cavium-octeon/setup.c
+++ b/arch/mips/cavium-octeon/setup.c

@@ -609,6 +609,12 @@ void octeon_user_io_init(void)
   #else
   	cvmmemctl.s.cvmsegenak = 0;
   #endif
+	if (OCTEON_IS_OCTEON3()) {
+		/* Enable LMTDMA */
+		cvmmemctl.s.lmtena = 1;
+		/* Scratch line to use for LMT operation */
+		cvmmemctl.s.lmtline = 2;

Out of curiosity, is there significance to the value 2 and associated
virtual address 0xffffffffffff8100, or is it pretty arbitrary?

Yes, there is significance.

CPU local memory starts at 0xffffffffffff8000, each line is 0x80 bytes.
so the 2nd line starts at 0xffffffffffff8100

What I mean is, why is 2 chosen instead of any other value?

That is explained in the change log of patch 5/8:


     1st 128-bytes: Use by IOBDMA
     2nd 128-bytes: Reserved by kernel for scratch/TLS emulation.
     3rd 128-bytes: OCTEON-III LMTLINE

Ah yes. Perhaps it deserves a brief comment in the code, or even an
enum.

Cheers
James