[PATCH] aarch64: Add FEAT_SCR2 System registers

[Alice Carlotti]

On Fri, Jan 16, 2026 at 03:30:07PM +0000, richard.ball@arm.com wrote:
> From: Richard Ball <Richard.Ball@arm.com>
> 
> This patch adds the system register "SCR2_EL3"
> Defined by FEAT_SCR2.

OK, thanks

Alice

> ---
>  gas/testsuite/gas/aarch64/sysreg/scr2-bad.d |  3 +++
>  gas/testsuite/gas/aarch64/sysreg/scr2-bad.l |  5 +++++
>  gas/testsuite/gas/aarch64/sysreg/scr2.d     | 10 ++++++++++
>  gas/testsuite/gas/aarch64/sysreg/scr2.s     |  3 +++
>  opcodes/aarch64-sys-regs.def                |  1 +
>  5 files changed, 22 insertions(+)
>  create mode 100644 gas/testsuite/gas/aarch64/sysreg/scr2-bad.d
>  create mode 100644 gas/testsuite/gas/aarch64/sysreg/scr2-bad.l
>  create mode 100644 gas/testsuite/gas/aarch64/sysreg/scr2.d
>  create mode 100644 gas/testsuite/gas/aarch64/sysreg/scr2.s
> 
> diff --git a/gas/testsuite/gas/aarch64/sysreg/scr2-bad.d b/gas/testsuite/gas/aarch64/sysreg/scr2-bad.d
> new file mode 100644
> index 00000000000..5b7143d6ebe
> --- /dev/null
> +++ b/gas/testsuite/gas/aarch64/sysreg/scr2-bad.d
> @@ -0,0 +1,3 @@
> +#as: -march=armv9.2-a -menable-sysreg-checking -I$srcdir/$subdir
> +#source:scr2.s
> +#error_output: scr2-bad.l
> \ No newline at end of file
> diff --git a/gas/testsuite/gas/aarch64/sysreg/scr2-bad.l b/gas/testsuite/gas/aarch64/sysreg/scr2-bad.l
> new file mode 100644
> index 00000000000..59c7e2c6181
> --- /dev/null
> +++ b/gas/testsuite/gas/aarch64/sysreg/scr2-bad.l
> @@ -0,0 +1,5 @@
> +.*: Assembler messages:
> +.*: Error: selected processor does not support system register name 'scr2_el3'
> +.*:  Info: macro invoked from here
> +.*: Error: selected processor does not support system register name 'scr2_el3'
> +.*:  Info: macro invoked from here
> \ No newline at end of file
> diff --git a/gas/testsuite/gas/aarch64/sysreg/scr2.d b/gas/testsuite/gas/aarch64/sysreg/scr2.d
> new file mode 100644
> index 00000000000..c784b576d12
> --- /dev/null
> +++ b/gas/testsuite/gas/aarch64/sysreg/scr2.d
> @@ -0,0 +1,10 @@
> +#as: -menable-sysreg-checking -march=armv9.3-a -I$srcdir/$subdir
> +#objdump: -dr
> +
> +.*:     file format .*
> +
> +Disassembly of section \.text:
> +
> +0+ <.*>:
> +.*:	d51e1240 	msr	scr2_el3, x0
> +.*:	d53e1240 	mrs	x0, scr2_el3
> diff --git a/gas/testsuite/gas/aarch64/sysreg/scr2.s b/gas/testsuite/gas/aarch64/sysreg/scr2.s
> new file mode 100644
> index 00000000000..8d1d424d4e5
> --- /dev/null
> +++ b/gas/testsuite/gas/aarch64/sysreg/scr2.s
> @@ -0,0 +1,3 @@
> +.include "sysreg-test-utils.inc"
> +
> +	rw_sys_reg scr2_el3
> diff --git a/opcodes/aarch64-sys-regs.def b/opcodes/aarch64-sys-regs.def
> index f4761438716..86d04b4a874 100644
> --- a/opcodes/aarch64-sys-regs.def
> +++ b/opcodes/aarch64-sys-regs.def
> @@ -1197,6 +1197,7 @@
>    SYSREG ("s2pir_el2",		CPENC (3,4,10,2,5),	0,		AARCH64_FEATURE (V8_8A)) /* S2PIE */
>    SYSREG ("s2por_el1",		CPENC (3,0,10,2,5),	0,		AARCH64_FEATURE (V8_8A)) /* S2POE */
>    SYSREG ("scr_el3",		CPENC (3,6,1,1,0),	0,		AARCH64_NO_FEATURES)
> +  SYSREG ("scr2_el3",		CPENC (3,6,1,2,2),	0,		AARCH64_FEATURE (V9_3A)) /* SCR2 */
>    SYSREG ("sctlr_el1",		CPENC (3,0,1,0,0),	0,		AARCH64_NO_FEATURES)
>    SYSREG ("sctlr_el12",		CPENC (3,5,1,0,0),	0,		AARCH64_NO_FEATURES)
>    SYSREG ("sctlr_el2",		CPENC (3,4,1,0,0),	0,		AARCH64_NO_FEATURES)
> -- 
> 2.34.1
>