With VHE, we place kernel {watch,break}-points at EL2 to get things like kgdb and "perf -e mem:..." working.
This requires a bit of repainting in the low-level encore/decode, but is otherwise pretty simple. Signed-off-by: Marc Zyngier <marc.zyng...@arm.com> --- arch/arm64/include/asm/hw_breakpoint.h | 49 +++++++++++++++++++++------------- 1 file changed, 31 insertions(+), 18 deletions(-) diff --git a/arch/arm64/include/asm/hw_breakpoint.h b/arch/arm64/include/asm/hw_breakpoint.h index 9732908..4d8d5a8 100644 --- a/arch/arm64/include/asm/hw_breakpoint.h +++ b/arch/arm64/include/asm/hw_breakpoint.h @@ -18,6 +18,7 @@ #include <asm/cputype.h> #include <asm/cpufeature.h> +#include <asm/virt.h> #ifdef __KERNEL__ @@ -35,24 +36,6 @@ struct arch_hw_breakpoint { struct arch_hw_breakpoint_ctrl ctrl; }; -static inline u32 encode_ctrl_reg(struct arch_hw_breakpoint_ctrl ctrl) -{ - return (ctrl.len << 5) | (ctrl.type << 3) | (ctrl.privilege << 1) | - ctrl.enabled; -} - -static inline void decode_ctrl_reg(u32 reg, - struct arch_hw_breakpoint_ctrl *ctrl) -{ - ctrl->enabled = reg & 0x1; - reg >>= 1; - ctrl->privilege = reg & 0x3; - reg >>= 2; - ctrl->type = reg & 0x3; - reg >>= 2; - ctrl->len = reg & 0xff; -} - /* Breakpoint */ #define ARM_BREAKPOINT_EXECUTE 0 @@ -62,6 +45,7 @@ static inline void decode_ctrl_reg(u32 reg, #define AARCH64_ESR_ACCESS_MASK (1 << 6) /* Privilege Levels */ +#define AARCH64_BREAKPOINT_EL2 0 #define AARCH64_BREAKPOINT_EL1 1 #define AARCH64_BREAKPOINT_EL0 2 @@ -76,6 +60,35 @@ static inline void decode_ctrl_reg(u32 reg, #define ARM_KERNEL_STEP_ACTIVE 1 #define ARM_KERNEL_STEP_SUSPEND 2 +#define DBG_HMC_HYP (1 << 13) +#define DBG_SSC_HYP (3 << 14) + +static inline u32 encode_ctrl_reg(struct arch_hw_breakpoint_ctrl ctrl) +{ + u32 val = (ctrl.len << 5) | (ctrl.type << 3) | ctrl.enabled; + + if (is_kernel_in_hyp_mode() && ctrl.privilege == AARCH64_BREAKPOINT_EL1) + val |= DBG_HMC_HYP | DBG_SSC_HYP | (AARCH64_BREAKPOINT_EL2 << 1); + else + val |= ctrl.privilege << 1; + + return val; +} + +static inline void decode_ctrl_reg(u32 reg, + struct arch_hw_breakpoint_ctrl *ctrl) +{ + ctrl->enabled = reg & 0x1; + reg >>= 1; + ctrl->privilege = reg & 0x3; + if (ctrl->privilege == AARCH64_BREAKPOINT_EL2) + ctrl->privilege = AARCH64_BREAKPOINT_EL1; + reg >>= 2; + ctrl->type = reg & 0x3; + reg >>= 2; + ctrl->len = reg & 0xff; +} + /* * Limits. * Changing these will require modifications to the register accessors. -- 2.1.4