[PATCH v2 07/10] arm64/debug: Simplify BRK insn opcode declarations

Mark Rutland
2015-07-13T14:38:35Z

On Mon, Jul 13, 2015 at 02:25:54PM +0100, Dave P Martin wrote:
> The way the KGDB_DYN_BRK_INS_BYTEx macros are declared is more
> complex than it needs to be. Also, the macros are only used in one
> place, which is arch-specific anyway.
>
> This patch refactors the macros to simplify them, and exposes an
> argument so that we can have a single macro instead of 4.
>
> As a side effect, this patch also fixes some anomalous spellings of
> "KGDB".
>
> Signed-off-by: Dave Martin <Dave.Martin@arm.com>

Acked-by: Mark Rutland <mark.rutland@arm.com>

Mark.

> ---
> arch/arm64/include/asm/debug-monitors.h | 23 ++++-------------------
> arch/arm64/kernel/kgdb.c | 8 ++++----
> 2 files changed, 8 insertions(+), 23 deletions(-)
>
> diff --git a/arch/arm64/include/asm/debug-monitors.h b/arch/arm64/include/asm/debug-monitors.h
> index e28b1dd..6a17fb8 100644
> --- a/arch/arm64/include/asm/debug-monitors.h
> +++ b/arch/arm64/include/asm/debug-monitors.h
> @@ -66,25 +66,10 @@
> */
> #define AARCH64_BREAK_FAULT (AARCH64_BREAK_MON | (FAULT_BRK_IMM << 5))
>
> -/*
> - * Extract byte from BRK instruction
> - */
> -#define KGDB_DYN_DBG_BRK_INS_BYTE(x) \
> - ((((AARCH64_BREAK_MON) & 0xffe0001f) >> (x * 8)) & 0xff)
> -
> -/*
> - * Extract byte from BRK #imm16
> - */
> -#define KGBD_DYN_DBG_BRK_IMM_BYTE(x) \
> - (((((KGDB_DYN_DBG_BRK_IMM) & 0xffff) << 5) >> (x * 8)) & 0xff)
> -
> -#define KGDB_DYN_DBG_BRK_BYTE(x) \
> - (KGDB_DYN_DBG_BRK_INS_BYTE(x) | KGBD_DYN_DBG_BRK_IMM_BYTE(x))
> -
> -#define KGDB_DYN_BRK_INS_BYTE0 KGDB_DYN_DBG_BRK_BYTE(0)
> -#define KGDB_DYN_BRK_INS_BYTE1 KGDB_DYN_DBG_BRK_BYTE(1)
> -#define KGDB_DYN_BRK_INS_BYTE2 KGDB_DYN_DBG_BRK_BYTE(2)
> -#define KGDB_DYN_BRK_INS_BYTE3 KGDB_DYN_DBG_BRK_BYTE(3)
> +#define AARCH64_BREAK_KGDB_DYN_DBG \
> + (AARCH64_BREAK_MON | (KGDB_DYN_DBG_BRK_IMM << 5))
> +#define KGDB_DYN_BRK_INS_BYTE(x) \
> + ((AARCH64_BREAK_KGDB_DYN_DBG >> (8 * (x))) & 0xff)
>
> #define CACHE_FLUSH_IS_SAFE 1
>
> diff --git a/arch/arm64/kernel/kgdb.c b/arch/arm64/kernel/kgdb.c
> index a5a838e..4f78b8a 100644
> --- a/arch/arm64/kernel/kgdb.c
> +++ b/arch/arm64/kernel/kgdb.c
> @@ -328,9 +328,9 @@ void kgdb_arch_exit(void)
> */
> struct kgdb_arch arch_kgdb_ops = {
> .gdb_bpt_instr = {
> - KGDB_DYN_BRK_INS_BYTE0,
> - KGDB_DYN_BRK_INS_BYTE1,
> - KGDB_DYN_BRK_INS_BYTE2,
> - KGDB_DYN_BRK_INS_BYTE3,
> + KGDB_DYN_BRK_INS_BYTE(0),
> + KGDB_DYN_BRK_INS_BYTE(1),
> + KGDB_DYN_BRK_INS_BYTE(2),
> + KGDB_DYN_BRK_INS_BYTE(3),
> }
> };
> --
> 1.7.10.4
>