@@ -9,3 +9,4 @@ HD-Audio
controls
dp-mst
realtek-pc-beep
+ intel-multi-link
new file mode 100644
@@ -0,0 +1,312 @@
+.. SPDX-License-Identifier: (GPL-2.0-only OR BSD-3-Clause)
+.. include:: <isonum.txt>
+
+================================================
+HDAudio multi-link extensions on Intel platforms
+================================================
+
+:Copyright: |copy| 2023 Intel Corporation
+
+This file documents the 'multi-link structure' introduced in 2015 with
+the Skylake processor and recently extended in newer Intel platforms
+
+HDaudio existing link mapping (2015 addition in SkyLake)
+========================================================
+
+External HDAudio codecs are handled with link #0, while iDISP codec
+for HDMI/DisplayPort is handled with link #1.
+
+The only change to the 2015 definitions is the declaration of the
+LCAP.ALT=0x0 - since the ALT bit was previously reserved, this is a
+backwards-compatible change.
+
+LCTL.SPA and LCTL.CPA are automatically set when exiting reset. They
+are only used in existing drivers when the SCF value needs to be
+corrected.
+
+Basic structure for HDaudio codecs
+----------------------------------
+
+::
+
+ +-----------+
+ | ML cap #0 |
+ +-----------+
+ | ML cap #1 |---+
+ +-----------+ |
+ |
+ +--> 0x0 +---------------+ LCAP
+ | ALT=0 |
+ +---------------+
+ | S192 |
+ +---------------+
+ | S96 |
+ +---------------+
+ | S48 |
+ +---------------+
+ | S24 |
+ +---------------+
+ | S12 |
+ +---------------+
+ | S6 |
+ +---------------+
+
+ 0x4 +---------------+ LCTL
+ | INTSTS |
+ +---------------+
+ | CPA |
+ +---------------+
+ | SPA |
+ +---------------+
+ | SCF |
+ +---------------+
+
+ 0x8 +---------------+ LOSIDV
+ | L1OSIVD15 |
+ +---------------+
+ | L1OSIDV.. |
+ +---------------+
+ | L1OSIDV1 |
+ +---------------+
+
+ 0xC +---------------+ LSDIID
+ | SDIID14 |
+ +---------------+
+ | SDIID... |
+ +---------------+
+ | SDIID0 |
+ +---------------+
+
+SoundWire HDaudio extended link mapping
+=======================================
+
+A SoundWire extended link is identified when LCAP.ALT=1 and
+LEPTR.ID=0.
+
+DMA control uses the existing LOSIDV register.
+
+Changes include additional descriptions for enumeration that were not
+present in earlier generations.
+
+- multi-link synchronization: capabilities in LCAP.LSS and control in LSYNC
+- number of sublinks (manager IP) in LCAP.LSCOUNT
+- power management moved from SHIM to LCTL.SPA bits
+- hand-over to the DSP for access to multi-link registers, SHIM/IP with LCTL.OFLEN
+- mapping of SoundWire codecs to SDI ID bits
+- move of SHIM and Cadence registers to different offsets, with no
+ change in functionality. The LEPTR.PTR value is an offset from the
+ ML address, with a default value of 0x30000.
+
+Extended structure for SoundWire (assuming 4 Manager IP)
+--------------------------------------------------------
+
+::
+
+ +-----------+
+ | ML cap #0 |
+ +-----------+
+ | ML cap #1 |
+ +-----------+
+ | ML cap #2 |---+
+ +-----------+ |
+ |
+ +--> 0x0 +---------------+ LCAP
+ | ALT=1 |
+ +---------------+
+ | INTC |
+ +---------------+
+ | OFLS |
+ +---------------+
+ | LSS |
+ +---------------+
+ | SLCOUNT=4 |-----------+
+ +---------------+ |
+ |
+ 0x4 +---------------+ LCTL |
+ | INTSTS | |
+ +---------------+ |
+ | CPA (x bits) | |
+ +---------------+ |
+ | SPA (x bits) | |
+ +---------------+ for each sublink x
+ | INTEN | |
+ +---------------+ |
+ | OFLEN | |
+ +---------------+ |
+ |
+ 0x8 +---------------+ LOSIDV |
+ | L1OSIVD15 | |
+ +---------------+ |
+ | L1OSIDV.. | |
+ +---------------+ |
+ | L1OSIDV1 | +---+----------------------------------------------------------+
+ +---------------+ | |
+ v |
+ 0xC + 0x2 * x +---------------+ LSDIIDx +---> 0x30000 +-----------------+ 0x00030000 |
+ | SDIID14 | | | SoundWire SHIM | |
+ +---------------+ | | generic | |
+ | SDIID... | | +-----------------+ 0x00030100 |
+ +---------------+ | | SoundWire IP | |
+ | SDIID0 | | +-----------------+ 0x00036000 |
+ +---------------+ | | SoundWire SHIM | |
+ | | vendor-specific | |
+ 0x1C +---------------+ LSYNC | +-----------------+ |
+ | CMDSYNC | | v
+ +---------------+ | +-----------------+ 0x00030000 + 0x8000 * x
+ | SYNCGO | | | SoundWire SHIM |
+ +---------------+ | | generic |
+ | SYNCPU | | +-----------------+ 0x00030100 + 0x8000 * x
+ +---------------+ | | SoundWire IP |
+ | SYNPRD | | +-----------------+ 0x00036000 + 0x8000 * x
+ +---------------+ | | SoundWire SHIM |
+ | | vendor-specific |
+ 0x20 +---------------+ LEPTR | +-----------------+
+ | ID = 0 | |
+ +---------------+ |
+ | VER | |
+ +---------------+ |
+ | PTR |------------+
+ +---------------+
+
+
+DMIC HDaudio extended link mapping
+==================================
+
+A DMIC extended link is identified when LCAP.ALT=1 and
+LEPTR.ID=0xC1 are set.
+
+DMA control uses the existing LOSIDV register
+
+Changes include additional descriptions for enumeration that were not
+present in earlier generations.
+
+- multi-link synchronization: capabilities in LCAP.LSS and control in LSYNC
+- power management with LCTL.SPA bits
+- hand-over to the DSP for access to multi-link registers, SHIM/IP with LCTL.OFLEN
+
+- move of DMIC registers to different offsets, with no change in
+ functionality. The LEPTR.PTR value is an offset from the ML
+ address, with a default value of 0x10000.
+
+Extended structure for DMIC
+---------------------------
+
+::
+
+ +-----------+
+ | ML cap #0 |
+ +-----------+
+ | ML cap #1 |
+ +-----------+
+ | ML cap #2 |---+
+ +-----------+ |
+ |
+ +--> 0x0 +---------------+ LCAP
+ | ALT=1 |
+ +---------------+
+ | INTC |
+ +---------------+
+ | OFLS |
+ +---------------+
+ | SLCOUNT=1 |
+ +---------------+
+
+ 0x4 +---------------+ LCTL
+ | INTSTS |
+ +---------------+
+ | CPA |
+ +---------------+
+ | SPA |
+ +---------------+
+ | INTEN |
+ +---------------+
+ | OFLEN |
+ +---------------+ +---> 0x10000 +-----------------+ 0x00010000
+ | | DMIC SHIM |
+ 0x8 +---------------+ LOSIDV | | generic |
+ | L1OSIVD15 | | +-----------------+ 0x00010100
+ +---------------+ | | DMIC IP |
+ | L1OSIDV.. | | +-----------------+ 0x00016000
+ +---------------+ | | DMIC SHIM |
+ | L1OSIDV1 | | | vendor-specific |
+ +---------------+ | +-----------------+
+ |
+ 0x20 +---------------+ LEPTR |
+ | ID = 0xC1 | |
+ +---------------+ |
+ | VER | |
+ +---------------+ |
+ | PTR |-----------+
+ +---------------+
+
+
+SSP HDaudio extended link mapping
+=================================
+
+A DMIC extended link is identified when LCAP.ALT=1 and
+LEPTR.ID=0xC0 are set.
+
+DMA control uses the existing LOSIDV register
+
+Changes include additional descriptions for enumeration and control that were not
+present in earlier generations:
+- number of sublinks (SSP IP instances) in LCAP.LSCOUNT
+- power management moved from SHIM to LCTL.SPA bits
+- hand-over to the DSP for access to multi-link registers, SHIM/IP
+with LCTL.OFLEN
+- move of SHIM and SSP IP registers to different offsets, with no
+change in functionality. The LEPTR.PTR value is an offset from the ML
+address, with a default value of 0x28000.
+
+Extended structure for SSP (assuming 3 instances of the IP)
+-----------------------------------------------------------
+
+::
+
+ +-----------+
+ | ML cap #0 |
+ +-----------+
+ | ML cap #1 |
+ +-----------+
+ | ML cap #2 |---+
+ +-----------+ |
+ |
+ +--> 0x0 +---------------+ LCAP
+ | ALT=1 |
+ +---------------+
+ | INTC |
+ +---------------+
+ | OFLS |
+ +---------------+
+ | SLCOUNT=3 |-------------------------for each sublink x -------------------------+
+ +---------------+ |
+ |
+ 0x4 +---------------+ LCTL |
+ | INTSTS | |
+ +---------------+ |
+ | CPA (x bits) | |
+ +---------------+ |
+ | SPA (x bits) | |
+ +---------------+ |
+ | INTEN | |
+ +---------------+ |
+ | OFLEN | |
+ +---------------+ +---> 0x28000 +-----------------+ 0x00028000 |
+ | | SSP SHIM | |
+ 0x8 +---------------+ LOSIDV | | generic | |
+ | L1OSIVD15 | | +-----------------+ 0x00028100 |
+ +---------------+ | | SSP IP | |
+ | L1OSIDV.. | | +-----------------+ 0x00028C00 |
+ +---------------+ | | SSP SHIM | |
+ | L1OSIDV1 | | | vendor-specific | |
+ +---------------+ | +-----------------+ |
+ | v
+ 0x20 +---------------+ LEPTR | +-----------------+ 0x00028000 + 0x1000 * x
+ | ID = 0xC0 | | | SSP SHIM |
+ +---------------+ | | generic |
+ | VER | | +-----------------+ 0x00028100 + 0x1000 * x
+ +---------------+ | | SSP IP |
+ | PTR |-----------+ +-----------------+ 0x00028C00 + 0x1000 * x
+ +---------------+ | SSP SHIM |
+ | vendor-specific |
+ +-----------------+