X-Git-Url: https://jxself.org/git/?p=linux-libre-firmware.git;a=blobdiff_plain;f=aica%2FDreamcast_sound.txt;fp=aica%2FDreamcast_sound.txt;h=08c3bacc6d44d31dab2a5886401770b8491b4a7d;hp=0000000000000000000000000000000000000000;hb=e02aa6cf5cbd5680016beaf879d7e1118124cb61;hpb=a8eb754461e1c033ecaf531dde9e312f9962ca0c

diff --git a/aica/Dreamcast_sound.txt b/aica/Dreamcast_sound.txt
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+SOUND ON THE SEGA DREAMCAST
+
+The Sega Dreamcast includes an ARM7 processor that separately handles sound
+playback. The ARM7 processor has its own address space which is only partially
+accessible to the main SH4 processor.
+
+The ALSA driver loads data to the ARM7 address space using DMA (which will
+run at a good speed). The old OSS driver did not use DMA and so showed
+very poor performance at high bit rates.
+
+The driver also loads some simple firmware (separately licenced under a 
+modified BSD licence) which controls the ARM7 processor. Without the 
+firmware the driver would merely fill the ARM7's address space and would 
+not playback any sound.
+
+The firmware, by default, should be loaded to /lib/firmware/ and should
+be named aica_firmware.bin.