iPod Classic: disable IRAM1

On Classic, IRAM1 (second 128Kb of a total of 256KB available IRAM) is
slower than DRAM. Codecs that actually are using regions of IRAM1 runs
faster when DRAM is used, so IRAM1 is disabled and only IRAM0 remains
enabled: 48KB for core and 80KB for codecs/plugins.

The next test_codec results shows how decode time is decreased:

file           boosted     unboosted
*.ra           ~1.5%       ~0.5%
*.mpc          ~21%        ~4.5%
*.ogg          ~0.5%       ~0%
nero_he*.m4a   ~8%         ~1%
nero*.m4a      ~25%        ~7%
wmapro*.wma    ~4.5%       ~0%
wma*.wma       ~25%        ~7%

In addition there is a small power save when IRAM1 HW is disabled.

Change-Id: I102adee11458e82037f23076d5d5956e23235de8

1 files changed, 3 insertions, 2 deletions

diff --git a/apps/plugins/plugin.lds b/apps/plugins/plugin.lds
index aea44e7d40..7037496be4 100644
--- a/apps/plugins/plugin.lds
+++ b/apps/plugins/plugin.lds
@@ -159,9 +159,10 @@ OUTPUT_FORMAT(elf32-littlemips)
 
 #elif CONFIG_CPU==S5L8702
 /* S5L8702 have 256KB of IRAM */
+/* IRAM1 (2nd 128KB block) is not used because it is slower than DRAM */
 #define DRAMORIG 0x08000000
-#define IRAMORIG (0x00000000 + (56*1024))
-#define IRAMSIZE (200*1024)
+#define IRAMORIG (0x00000000 + (48*1024))
+#define IRAMSIZE (80*1024)
 
 #elif CONFIG_CPU == JZ4732 || CONFIG_CPU == JZ4760B
 #undef STUBOFFSET