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iPod Classic: disable IRAM1

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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
This commit is contained in:
Cástor Muñoz 2017-01-13 20:51:07 +01:00 • committed by Franklin Wei
parent 8f38f85fbd
commit 7442742208
11 changed files with 25 additions and 20 deletions
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5
apps/plugins/plugin.lds
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@ -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