TRCVIPCSSCTLR: Trace ViewInst Start/Stop PE Comparator Control Register

Purpose

Use this to select, or read, which PE Comparator Inputs can control the ViewInst start/stop function.

Configuration

External register TRCVIPCSSCTLR bits [31:0] are architecturally mapped to AArch64 System register TRCVIPCSSCTLR[31:0].

This register is present only when FEAT_ETE is implemented, FEAT_TRC_EXT is implemented and UInt(TRCIDR4.NUMPC) > 0. Otherwise, direct accesses to TRCVIPCSSCTLR are RES0.

Attributes

TRCVIPCSSCTLR is a 32-bit register.

Field descriptions

31	30	29	28	27	26	25	24	23	22	21	20	19	18	17	16	15	14	13	12	11	10	9	8	7	6	5	4	3	2	1	0
RES0								STOP[7]	STOP[6]	STOP[5]	STOP[4]	STOP[3]	STOP[2]	STOP[1]	STOP[0]	RES0								START[7]	START[6]	START[5]	START[4]	START[3]	START[2]	START[1]	START[0]

Bits [31:24]

Reserved, RES0.

STOP[<m>], bit [m+16], for m = 7 to 0

Selects whether PE Comparator Input <m> is in use with the ViewInst start/stop function for the purpose of stopping trace.

STOP[<m>]	Meaning
0b0	The PE Comparator Input <m> is not selected as a stop resource.
0b1	The PE Comparator Input <m> is selected as a stop resource.

The reset behavior of this field is:

On a Trace unit reset, this field resets to an architecturally UNKNOWN value.

Accessing this field has the following behavior:

When m >= UInt(TRCIDR4.NUMPC), access to this field is RES0.
Otherwise, access to this field is RW.

Bits [15:8]

Reserved, RES0.

START[<m>], bit [m], for m = 7 to 0

Selects whether PE Comparator Input <m> is in use with the ViewInst start/stop function for the purpose of starting trace.

START[<m>]	Meaning
0b0	The PE Comparator Input <m> is not selected as a start resource.
0b1	The PE Comparator Input <m> is selected as a start resource.

The reset behavior of this field is:

On a Trace unit reset, this field resets to an architecturally UNKNOWN value.

Accessing this field has the following behavior:

When m >= UInt(TRCIDR4.NUMPC), access to this field is RES0.
Otherwise, access to this field is RW.

Accessing TRCVIPCSSCTLR

Must be programmed if TRCIDR4.NUMPC != 0b0000.

Writes are CONSTRAINED UNPREDICTABLE if the trace unit is not in the Idle state.

TRCVIPCSSCTLR can be accessed through the external debug interface:

Component	Offset	Instance
ETE	0x08C	TRCVIPCSSCTLR

This interface is accessible as follows:

When OSLockStatus(), or !AllowExternalTraceAccess() or !IsTraceCorePowered(), accesses to this register generate an error response.
Otherwise, accesses to this register are RW.