freedreno/regs: Document a7xx CP_BV_BR_COUNT_OPS

Fully tested on HW. Credits to Connor Abbott for finding out how
it works.

Signed-off-by: Danylo Piliaiev <dpiliaiev@igalia.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/23881>

diff --git a/src/freedreno/registers/adreno/adreno_pm4.xml b/src/freedreno/registers/adreno/adreno_pm4.xml
index f119443..8ab7b43 100644 (file)
--- a/src/freedreno/registers/adreno/adreno_pm4.xml
+++ b/src/freedreno/registers/adreno/adreno_pm4.xml
@@ -626,7 +626,8 @@ xsi:schemaLocation="http://nouveau.freedesktop.org/ rules-ng.xsd">
        <value name="CP_THREAD_CONTROL" value="0x17" variants="A7XX-"/>
        <!-- payload 4 dwords, last two could be render target addr (one pkt per MRT), possibly used for GMEM save/restore?-->
        <value name="CP_RESOURCE_LIST" value="0x18" variants="A7XX-"/>
-       <value name="CP_BV_BR_COUNT_OPS" value="0x1b" variants="A7XX-"/>  <!-- payload 1 or 2 dwords -->
+       <doc> Can clear BV/BR counters, or wait until one catches up to another </doc>
+       <value name="CP_BV_BR_COUNT_OPS" value="0x1b" variants="A7XX-"/>
        <doc> Clears, adds to local, or adds to global timestamp </doc>
        <value name="CP_MODIFY_TIMESTAMP" value="0x1c" variants="A7XX-"/>
        <!-- similar to CP_CONTEXT_REG_BUNCH, but discards first two dwords?? -->
@@ -2159,6 +2160,23 @@ opcode: CP_LOAD_STATE4 (30) (4 dwords)
        <reg32 offset="4" name="SRC_1"/>
 </domain>
 
+<domain name="CP_BV_BR_COUNT_OPS" width="32">
+       <enum name="pipe_count_op">
+               <value name="PIPE_CLEAR_BV_BR" value="0x1"/>
+               <value name="PIPE_SET_BR_OFFSET" value="0x2"/>
+               <!-- Wait until for BV_counter > BR_counter -->
+               <value name="PIPE_BR_WAIT_FOR_BV" value="0x3"/>
+               <!-- Wait until (BR_counter + BR_OFFSET) > BV_counter -->
+               <value name="PIPE_BV_WAIT_FOR_BR" value="0x4"/>
+       </enum>
+       <reg32 offset="0" name="0">
+               <bitfield name="OP" low="0" high="3" type="pipe_count_op"/>
+       </reg32>
+       <reg32 offset="1" name="1">
+               <bitfield name="BR_OFFSET" low="0" high="15" type="uint"/>
+       </reg32>
+</domain>
+
 <domain name="CP_MODIFY_TIMESTAMP" width="32">
        <enum name="timestamp_op">
                <value name="MODIFY_TIMESTAMP_CLEAR" value="0"/>