TILER: Add menuconfig and memparse support for cache_limit setting.

tiler.cache now can be specified as a memory, such as "40M".

Also added TILER_CACHE_LIMIT config to set cache limit in MB.

Signed-off-by: Lajos Molnar <molnar@ti.com>
Signed-off-by: David Sin <davidsin@ti.com>

2 files changed, 45 insertions, 2 deletions

diff --git a/drivers/media/video/tiler/Kconfig b/drivers/media/video/tiler/Kconfig
index 13570ed9f88..8ff8ede9164 100644
--- a/drivers/media/video/tiler/Kconfig
+++ b/drivers/media/video/tiler/Kconfig
@@ -46,6 +46,24 @@ config TILER_ALIGNMENT
            Supported values are: 1, 2, 4, 8, 16, 32, 64, 128, 256, 512, 1024,
            2048, 4096.
 
+config TILER_CACHE_LIMIT
+        int "Memory limit to cache free pages in MBytes"
+        range 0 128
+        default 40
+        depends on TI_TILER
+        help
+           This option sets the minimum memory that TILER retains even if
+           there is less TILER allocated memory is use.  The unused memory is
+           instead stored in a cache to speed up allocation and freeing of
+           physical pages.
+
+           This option can be overriden by the tiler.cache boot argument.
+
+           While initially TILER will use less memory than this limit (0), it
+           will not release any memory used until it reaches this limit.
+           Thereafter, TILER will release any unused memory immediately as
+           long as there it is above this threshold.
+
 config TILER_SECURITY
         int "Process security"
         range 0 1
diff --git a/drivers/media/video/tiler/tmm-pat.c b/drivers/media/video/tiler/tmm-pat.c
index 0e50fa35912..bfef67cbe39 100644
--- a/drivers/media/video/tiler/tmm-pat.c
+++ b/drivers/media/video/tiler/tmm-pat.c
@@ -26,9 +26,14 @@
 
 #include "tmm.h"
 
+static int param_set_mem(const char *val, struct kernel_param *kp);
+
 /* Memory limit to cache free pages. TILER will eventually use this much */
-static u32 cache_limit = (40 * 1024 * 1024);
-module_param_named(cache, cache_limit, uint, 0644);
+static u32 cache_limit = CONFIG_TILER_CACHE_LIMIT << 20;
+
+param_check_uint(cache, &cache_limit);
+module_param_call(cache, param_set_mem, param_get_uint, &cache_limit, 0644);
+__MODULE_PARM_TYPE(cache, "uint")
 MODULE_PARM_DESC(cache, "Cache free pages if total memory is under this limit");
 
 /* global state - statically initialized */
@@ -58,6 +63,26 @@ struct dmm_mem {
         struct dmm *dmm;
 };
 
+/* read mem values for a param */
+static int param_set_mem(const char *val, struct kernel_param *kp)
+{
+        u32 a;
+        char *p;
+
+        /* must specify memory */
+        if (!val)
+                return -EINVAL;
+
+        /* parse value */
+        a = memparse(val, &p);
+        if (p == val || *p)
+                return -EINVAL;
+
+        /* store parsed value */
+        *(uint *)kp->arg = a;
+        return 0;
+}
+
 /**
  *  Frees pages in a fast structure.  Moves pages to the free list if there
  *  are less pages used than max_to_keep.  Otherwise, it frees the pages