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39 lines
937 B
Plaintext
39 lines
937 B
Plaintext
PIO VS dma
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driver is DIRECTLY modifying pfifo
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8X8 channel setup
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Names are 32-bit integers >4096
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RAMFC - DMA Context object 0,0 to 8,8
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context = channel, render object, object type, offset in instance memory
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for a rectangle (type 0x47), object render = 1, channel 0, at 0x0400 in the ramht memory
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=0x00c70400 as the context
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the ramht hash :
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xor every byte of the hash individually and then xor that with the channel number
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so obj id 01020304 in channel 0 is 1 xor 2 xor 3 xor 4 xor 0
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Store in RAMHT at <subchannel start within RAMHT> + 4*16 = name
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Store in RAMHT at <subchannel start within RAMHT> + 4*16 + 4 = context
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then the ramin stuff starts at *0xc04000 since c00000 is the start of ramin [PCI BAR1] which is where you put the contents of the class struct
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nv_user
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Consider the 8x8 channels as 64 subchannels.
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Now you can do:
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They seem to end at 0x880000
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(0x880000)/64 = 0x2000 for each channel
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FAILURE -> RAMRO!
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