DSP - Revision history

JayFoxRox: Add explicit link to family manual, because people don't seem to find it

2019-02-03T17:17:46Z

Add explicit link to family manual, because people don't seem to find it

JayFoxRox: Add link to xboxpy scripts

2019-02-03T17:16:39Z

Add link to xboxpy scripts

JayFoxRox: Describe FIFOs

2019-01-25T16:21:31Z

Describe FIFOs

JayFoxRox: Add some FIXMEs for untested cases

2018-12-30T04:58:52Z

Add some FIXMEs for untested cases

JayFoxRox at 16:03, 29 December 2018

2018-12-29T16:03:32Z

JayFoxRox: Noticed that this can only apply to scratch (FIFO is also circular, but doesn't use these fields - to my knowledge)

2018-12-28T23:08:16Z

Noticed that this can only apply to scratch (FIFO is also circular, but doesn't use these fields - to my knowledge)

JayFoxRox: Interleaved mode (DSP address) does not affect buffer offset writeback (Buffer offset) due to diffeent address spaces

2018-12-28T23:01:11Z

Interleaved mode (DSP address) does not affect buffer offset writeback (Buffer offset) due to diffeent address spaces

JayFoxRox: /* Command blocks */

2018-12-28T20:13:09Z

‎Command blocks

JayFoxRox: Document interleaved mode + Formatting

2018-12-28T20:03:46Z

Document interleaved mode + Formatting

JayFoxRox: /* Command blocks */

2018-12-28T13:52:51Z

‎Command blocks

@@ Line 1: / Line 1: @@
 The DSPs in the APU are probably "Parthus MediaStream" DSP cores (probably the 24-bit DSP2420 "Mozart" core).
-Those are similar to Motorola DSP56362 (DSP56300 Family). If so, the datasheet can be found at http://www.nxp.com/docs/en/data-sheet/DSP56362.pdf (Also see "Documentation" section in said datasheet for the related documentation)
+Those are similar to Motorola DSP56362 (DSP56300 Family). If so, the datasheet can be found at http://www.nxp.com/docs/en/data-sheet/DSP56362.pdf (Also see "Documentation" section in said datasheet for the related documentation, like [https://www.nxp.com/docs/en/reference-manual/DSP56300FM.pdf the family manual])
 == Memory Size ==

@@ Line 213: / Line 213: @@
 * [https://github.com/XboxDev/a56 Modernized fork of a56, open-source assembler for the similar 56000 architecture]
 * [https://web.archive.org/web/20010212122052/http://www.parthus.com:80/platforms/parthus_mediastream/index.html MediaStream product page]
 * [https://web.archive.org/web/20011130084353/http://www.fs2.com:80/parthus_download/ First Silicon MediaStream tools]

← Older revision		Revision as of 16:21, 25 January 2019
Line 188:		Line 188:

	=== FIFO ===		=== FIFO ===
		+
		+	{{FIXME\|reason=Document register names? The FIFO registers are already defined in the XQEMU source}}
		+
		+	Each of the DSP has 4 output FIFOs, and 2 input FIFOs.
		+
		+	All FIFOs belonging to the same DSP share the memory view. The memory view is controlled in the DSPs FIFO Scatter-Gather entries.
		+
		+	Each FIFO has 3 address registers, which define a ringbuffer:
		+
		+	* Base address: The address of the first byte in the FIFO.
		+	* End address: The address of the first byte that's no longer part of the FIFO (so this address is exclusive).
		+	* Current address: The absolute address of the next byte that will be written.
		+
		+	During a transfer, the current address is incremented.
		+	If the current address hits the end address during a transfer, the current address is moved to the base, where the transfer continues.
		+
		+	If the transfer length is greater than the FIFO length when using the output FIFO, the transfer will continue normally and overwrite previously transferred bytes.
		+	If the transfer length is greater than the FIFO length when using the input FIFO, the transfer will continue normally and read previously transferred bytes again.

	If the current address is below the base address when starting a transfer, it is moved to the base address.		If the current address is below the base address when starting a transfer, it is moved to the base address.

@@ Line 60: / Line 60: @@
 | Transfer control word || Controls the DMA transfer:
-'''DSP address interleave (Bit-offset 0; 1-bit):'''
+'''DSP address interleave (Bit-offset 0; 1-bit):'''{{FIXME|reason=How is addressing affected with sample format 0x3 = 32 bit words?}}
 <ul>
 <li>0 = Addressing using:<pre>
@@ Line 112: / Line 112: @@
 '''Sample format (Bit-offset 10; 3-bits):''' ''{{FIXME|reason=Some of these need tests with signed datatypes}}''
-* 0x0 = 8 bit (1 DSP word / 1 byte); ''sample-count must be multiple of 4, or transfer is skipped; rounded; byte MSB is flipped''
+* 0x0 = 8 bit (1 DSP word / 1 byte); ''sample-count must be multiple of 4, or transfer is skipped; rounded; byte MSB is flipped''{{FIXME|reason=How are negative input words affected by rounding? 0x123000 etc.}}
 ** Buffer to DSP: bytes: <code>0x12,0x34,0x56,0x78</code> &rarr; words: <code>0x920000, 0xB40000, 0xD60000, 0xF80000</code>
 ** Buffer to DSP: bytes: <code>0x92,0xB4,0xD6,0xF8</code> &rarr; words: <code>0x120000, 0x340000, 0x560000, 0x780000</code>

← Older revision		Revision as of 16:03, 29 December 2018
Line 198:		Line 198:
	* [https://web.archive.org/web/20011130084353/http://www.fs2.com:80/parthus_download/ First Silicon MediaStream tools]		* [https://web.archive.org/web/20011130084353/http://www.fs2.com:80/parthus_download/ First Silicon MediaStream tools]
	* [https://web.archive.org/web/20020213235936/http://www.tasking.com/products/MediaStream/index.html Tasking MediaStream compiler]		* [https://web.archive.org/web/20020213235936/http://www.tasking.com/products/MediaStream/index.html Tasking MediaStream compiler]
		+
		+	[[Category:APU]]

@@ Line 179: / Line 179: @@
 |-
 ! 5
-| Buffer base || ''Only used for circular buffers, ignored otherwise.''{{FIXME|reason=Assumption; it happens for buffer 0xE, but not for buffer 0xF}}
+| Buffer base || ''Only used for circular scratch buffer, ignored otherwise.''{{FIXME|reason=Assumption; it happens for buffer 0xE, but not for buffer 0xF}}
 The start address of the buffer.
 |-
 ! 6
-| Buffer size || ''Only used for circular buffers, ignored otherwise.''{{FIXME|reason=Assumption; it happens for buffer 0xE, but not for buffer 0xF}}
+| Buffer size || ''Only used for circular scratch buffer, ignored otherwise.''{{FIXME|reason=Assumption; it happens for buffer 0xE, but not for buffer 0xF}}
 Size of buffer minus 1. For a buffer with 0x1000 bytes, this has to be 0xFFF.
 |}

@@ Line 156: / Line 156: @@
+:
+:
-* Interleaved mode:{{FIXME|reason=What's the new buffer address when using buffer offset writeback?}}
+* Interleaved mode:
+:
 : '''Channel count (Bit-offset 0; 4-bits):'''

@@ Line 162: / Line 162: @@
+:
 : '''Block count (Bit-offset 4; 20-bits):'''
-: The number of blocks.
+: The number of blocks to be transferred.
+:
+:

@@ Line 60: / Line 60: @@
 | Transfer control word || Controls the DMA transfer:
-* Unknown (Bit-offset 0; 1-bit).
+'''DSP address interleave (Bit-offset 0; 1-bit):'''
-** 0 = ?
+<ul>
-** 1 = ?
+<li>0 = Addressing using:<pre>
-* Direction (Bit-offset 1; 1-bit).
+'''Direction (Bit-offset 1; 1-bit):'''
-** 0 = Buffer to DSP (In)
+* 0 = Buffer to DSP (In)
-** 1 = DSP to buffer (Out)
+* 1 = DSP to buffer (Out)
-* Unknown (Bit-offset 2; 2-bit).
+'''Unknown (Bit-offset 2; 2-bits):'''
-** 0 = ?
+* 0 = ?
-** 1 = ?
+* 1 = ?
-** 2 = ?
+* 2 = ?
-** 3 = ?
+* 3 = ?
-* Buffer offset writeback (Bit-offset 4; 1-bit). ''Only used for scratch buffers, behaves like 0 otherwise.''{{FIXME|reason=Assumption; Didn't do anything for FIFO0. Not sure if I documented this for 0xE or 0xF}}
+'''Buffer offset writeback (Bit-offset 4; 1-bit):'''
-** 0 = Don't update buffer offset (Word 4)
+''Only used for scratch buffers, behaves like 0 otherwise.''{{FIXME|reason=Assumption; Didn't do anything for FIFO0. Not sure if I documented this for 0xE or 0xF}}
-** 1 = Update buffer offset (Word 4); this respects address wrapping of circular buffers
+* 0 = Don't update buffer offset (Word 4)
-* Buffer (Bit-offset 5; 4-bits).
+'''Buffer (Bit-offset 5; 4-bits):'''
-** 0x0 = FIFO0 (In / Out)
+* 0x0 = FIFO0 (In / Out)
-** 0x1 = FIFO1 (In / Out)
+* 0x1 = FIFO1 (In / Out)
-** 0x2 = FIFO2 (Out only; Buffer to DSP is ignored)
+* 0x2 = FIFO2 (Out only; Buffer to DSP is ignored)
-** 0x3 = FIFO3 (Out only; Buffer to DSP is ignored)
+* 0x3 = FIFO3 (Out only; Buffer to DSP is ignored)
-** 0x4 = ?
+* 0x4 = ?
-** 0x5 = ?
+* 0x5 = ?
-** 0x6 = ?
+* 0x6 = ?
-** 0x7 = ?
+* 0x7 = ?
-** 0x8 = ?
+* 0x8 = ?
-** 0x9 = ?
+* 0x9 = ?
-** 0xA = ?
+* 0xA = ?
-** 0xB = ?
+* 0xB = ?
-** 0xC = ?
+* 0xC = ?
-** 0xD = ?
+* 0xD = ?
-** 0xE = Scratch (Circular)
+* 0xE = Scratch (Circular)
-** 0xF = Scratch
+* 0xF = Scratch
-* Unknown (Bit-offset 9; 1-bit).
+'''Unknown (Bit-offset 9; 1-bit):'''
-** 0 = ?
+* 0 = ?
-** 1 = ?
+* 1 = ?
-* Sample format (Bit-offset 10; 3-bits).{{FIXME|reason=Some of these need tests with signed datatypes}}
+'''Sample format (Bit-offset 10; 3-bits):''' ''{{FIXME|reason=Some of these need tests with signed datatypes}}''
-** 0x0 = 8 bit (1 DSP word / 1 byte); ''sample-count must be multiple of 4, or transfer is skipped; rounded; byte MSB is flipped''
+* 0x0 = 8 bit (1 DSP word / 1 byte); ''sample-count must be multiple of 4, or transfer is skipped; rounded; byte MSB is flipped''
-*** Buffer to DSP: bytes: <code>0x12,0x34,0x56,0x78</code> &rarr; words: <code>0x920000, 0xB40000, 0xD60000, 0xF80000</code>
+** Buffer to DSP: bytes: <code>0x12,0x34,0x56,0x78</code> &rarr; words: <code>0x920000, 0xB40000, 0xD60000, 0xF80000</code>
-*** Buffer to DSP: bytes: <code>0x92,0xB4,0xD6,0xF8</code> &rarr; words: <code>0x120000, 0x340000, 0x560000, 0x780000</code>
+** Buffer to DSP: bytes: <code>0x92,0xB4,0xD6,0xF8</code> &rarr; words: <code>0x120000, 0x340000, 0x560000, 0x780000</code>
-*** DSP to buffer: words: <code>0x927FFF, 0xB47FFF, 0xD67FFF, 0xF87FFF</code> &rarr; bytes: <code>0x12,0x34,0x56,0x78</code> ''(Rounded down)''
+** DSP to buffer: words: <code>0x927FFF, 0xB47FFF, 0xD67FFF, 0xF87FFF</code> &rarr; bytes: <code>0x12,0x34,0x56,0x78</code> ''(Rounded down)''
-*** DSP to buffer: words: <code>0x928000, 0xB48000, 0xD68000, 0xF88000</code> &rarr; bytes: <code>0x13,0x35,0x57,0x79</code> ''(Rounded up)''
+** DSP to buffer: words: <code>0x928000, 0xB48000, 0xD68000, 0xF88000</code> &rarr; bytes: <code>0x13,0x35,0x57,0x79</code> ''(Rounded up)''
-*** DSP to buffer: words: <code>0x800000, 0x7E7FFF, 0x7E8000, 0x7FFFFF</code> &rarr; bytes: <code>0x00,0xFE,0xFF,0xFF</code> ''(Saturated)''
+** DSP to buffer: words: <code>0x800000, 0x7E7FFF, 0x7E8000, 0x7FFFFF</code> &rarr; bytes: <code>0x00,0xFE,0xFF,0xFF</code> ''(Saturated)''
-** 0x1 = 16 bit (1 DSP word / 2 bytes) ''sample-count must be multiple of 2, or transfer is skipped; truncated''
+* 0x1 = 16 bit (1 DSP word / 2 bytes) ''sample-count must be multiple of 2, or transfer is skipped; truncated''
-*** Buffer to DSP: bytes: <code>0x34,0x12</code> &rarr; word: <code>0x123400</code>
+** Buffer to DSP: bytes: <code>0x34,0x12</code> &rarr; word: <code>0x123400</code>
-*** DSP to buffer: word: <code>0x1234FF</code> &rarr; bytes: <code>0x34,0x12</code> ''(Truncated)''
+** DSP to buffer: word: <code>0x1234FF</code> &rarr; bytes: <code>0x34,0x12</code> ''(Truncated)''
-*** DSP to buffer: word: <code>0x123400</code> &rarr; bytes: <code>0x34,0x12</code> ''(Truncated)''
+** DSP to buffer: word: <code>0x123400</code> &rarr; bytes: <code>0x34,0x12</code> ''(Truncated)''
-** 0x2 = 24 bit in MSB (1 DSP word / 4 bytes); ''padded''
+* 0x2 = 24 bit in MSB (1 DSP word / 4 bytes); ''padded''
-*** Buffer to DSP: bytes: <code>0x00,0x56,0x34,0x12</code> &rarr; word: <code>0x123456</code> ''(Padding ignored)''
+** Buffer to DSP: bytes: <code>0x00,0x56,0x34,0x12</code> &rarr; word: <code>0x123456</code> ''(Padding ignored)''
-*** Buffer to DSP: bytes: <code>0xFF,0x56,0x34,0x12</code> &rarr; word: <code>0x123456</code> ''(Padding ignored)''
+** Buffer to DSP: bytes: <code>0xFF,0x56,0x34,0x12</code> &rarr; word: <code>0x123456</code> ''(Padding ignored)''
-*** DSP to buffer: word: <code>0x123456</code> &rarr; bytes: <code>0x00,0x56,0x34,0x12</code> ''(Zero padding)''
+** DSP to buffer: word: <code>0x123456</code> &rarr; bytes: <code>0x00,0x56,0x34,0x12</code> ''(Zero padding)''
-** 0x3 = 32 bit (2 DSP words / 4 bytes); ''trunacted''
+* 0x3 = 32 bit (2 DSP words / 4 bytes); ''trunacted''
-*** Buffer to DSP: bytes: <code>0x12,0xBC,0x9A,0x78</code> &rarr; words: <code>0x120000, 0x789ABC</code>
+** Buffer to DSP: bytes: <code>0x12,0xBC,0x9A,0x78</code> &rarr; words: <code>0x120000, 0x789ABC</code>
-*** DSP to buffer: words: <code>0x12FFFF, 0x789ABC</code> &rarr; bytes: <code>0x12,0xBC,0x9A,0x78</code> ''(Truncated)''
+** DSP to buffer: words: <code>0x12FFFF, 0x789ABC</code> &rarr; bytes: <code>0x12,0xBC,0x9A,0x78</code> ''(Truncated)''
-*** DSP to buffer: words: <code>0x120000, 0x789ABC</code> &rarr; bytes: <code>0x12,0xBC,0x9A,0x78</code> ''(Truncated)''
+** DSP to buffer: words: <code>0x120000, 0x789ABC</code> &rarr; bytes: <code>0x12,0xBC,0x9A,0x78</code> ''(Truncated)''
-** 0x4 = ''Transfer skipped''
+* 0x4 = ''Transfer skipped''
-** 0x5 = ''Transfer skipped''
+* 0x5 = ''Transfer skipped''
-** 0x6 = 24 bit in LSB (1 DSP word / 4 bytes); ''padded''
+* 0x6 = 24 bit in LSB (1 DSP word / 4 bytes); ''padded''
-*** Buffer to DSP: bytes: <code>0x56,0x34,0x12,0x00</code> &rarr; word: <code>0x123456</code> ''(Padding ignored)''
+** Buffer to DSP: bytes: <code>0x56,0x34,0x12,0x00</code> &rarr; word: <code>0x123456</code> ''(Padding ignored)''
-*** Buffer to DSP: bytes: <code>0x56,0x34,0x12,0xFF</code> &rarr; word: <code>0x123456</code> ''(Padding ignored)''
+** Buffer to DSP: bytes: <code>0x56,0x34,0x12,0xFF</code> &rarr; word: <code>0x123456</code> ''(Padding ignored)''
-*** DSP to buffer: word: <code>0x123456</code> &rarr; bytes: <code>0x56,0x34,0x12,0x00</code> ''(Zero padding)''
+** DSP to buffer: word: <code>0x123456</code> &rarr; bytes: <code>0x56,0x34,0x12,0x00</code> ''(Zero padding)''
-** 0x7 = ''Transfer skipped''
+* 0x7 = ''Transfer skipped''
-* Unknown (Bit-offset 13; 1-bit).
+'''Unknown (Bit-offset 13; 1-bit):'''
-** 0 = ?
+* 0 = ?
-** 1 = ?
+* 1 = ?
-* DSP address step size (Bit-offset 14; unknown size).
+'''DSP address step size (Bit-offset 14; 10-bits):'''
-** Each DSP word is addressed using <code>dsp_address + sample_index * step_size</code>
 |-
 ! 2
-| Transfer sample count || The number of samples to transfer.
+| Sample count || Behaviour depends on interleave setting
 |-
 ! 3