[PATCH 1/2] MIPS: Introduce CAVIUM_RESERVE32 Kconfig option

From: Alexander A Sverdlin
Date: Mon Jul 25 2022 - 05:18:01 EST


From: Alexander Sverdlin <alexander.sverdlin@xxxxxxxxx>

This options is used to reserve a shared memory region for user processes
to use for hardware memory buffers. The actual code to support the option
comes in the following patch.

Signed-off-by: Corey Minyard <cminyard@xxxxxxxxxx>
Signed-off-by: Alexander Sverdlin <alexander.sverdlin@xxxxxxxxx>
---
arch/mips/cavium-octeon/Kconfig | 12 ++++++++++++
1 file changed, 12 insertions(+)

diff --git a/arch/mips/cavium-octeon/Kconfig b/arch/mips/cavium-octeon/Kconfig
index 4984e46..c1899f1 100644
--- a/arch/mips/cavium-octeon/Kconfig
+++ b/arch/mips/cavium-octeon/Kconfig
@@ -67,6 +67,18 @@ config CAVIUM_OCTEON_LOCK_L2_MEMCPY
help
Lock the kernel's implementation of memcpy() into L2.

+config CAVIUM_RESERVE32
+ int "Memory to reserve for user processes shared region (MB)"
+ range 0 1536
+ default "0"
+ help
+ Reserve a shared memory region for user processes to use for hardware
+ memory buffers. This is required for 32bit applications to be able to
+ send and receive packets directly. Applications access this memory by
+ memory mapping /dev/mem for the addresses in /proc/octeon_info. For
+ optimal performance with HugeTLBs, keep this size an even number of
+ megabytes.
+
config OCTEON_ILM
tristate "Module to measure interrupt latency using Octeon CIU Timer"
help
--
2.10.2