From 81c53ed8412ddfe5e3e4c59715b6d6a937bd0240 Mon Sep 17 00:00:00 2001
From: Michael Neuling <mikey@neuling.org>
Date: Tue, 27 Mar 2018 15:37:17 +1100
Subject: [PATCH 1/9] powerpc: Add ppc_breakpoint_available()
References: bsc#1055117
Patch-mainline: v4.17-rc1
Git-commit: 404b27d66ed657ebccb08a9c8f8f65523e9b666b
Add ppc_breakpoint_available() to determine if a breakpoint is
available currently via the DAWR or DABR.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Acked-by: Michal Suchanek <msuchanek@suse.de>
---
arch/powerpc/include/asm/debug.h | 1 +
arch/powerpc/kernel/process.c | 12 ++++++++++++
2 files changed, 13 insertions(+)
diff --git a/arch/powerpc/include/asm/debug.h b/arch/powerpc/include/asm/debug.h
index 5d5af3fddfd8..346c6f5c248d 100644
--- a/arch/powerpc/include/asm/debug.h
+++ b/arch/powerpc/include/asm/debug.h
@@ -46,6 +46,7 @@ static inline int debugger_fault_handler(struct pt_regs *regs) { return 0; }
void set_breakpoint(struct arch_hw_breakpoint *brk);
void __set_breakpoint(struct arch_hw_breakpoint *brk);
+bool ppc_breakpoint_available(void);
#ifdef CONFIG_PPC_ADV_DEBUG_REGS
extern void do_send_trap(struct pt_regs *regs, unsigned long address,
unsigned long error_code, int signal_code, int brkpt);
diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c
index 284e58f59d4f..8297177321d8 100644
--- a/arch/powerpc/kernel/process.c
+++ b/arch/powerpc/kernel/process.c
@@ -844,6 +844,18 @@ void set_breakpoint(struct arch_hw_breakpoint *brk)
preempt_enable();
}
+/* Check if we have DAWR or DABR hardware */
+bool ppc_breakpoint_available(void)
+{
+ if (cpu_has_feature(CPU_FTR_DAWR))
+ return true; /* POWER8 DAWR */
+ if (cpu_has_feature(CPU_FTR_ARCH_207S))
+ return false; /* POWER9 with DAWR disabled */
+ /* DABR: Everything but POWER8 and POWER9 */
+ return true;
+}
+EXPORT_SYMBOL_GPL(ppc_breakpoint_available);
+
#ifdef CONFIG_PPC64
DEFINE_PER_CPU(struct cpu_usage, cpu_usage_array);
#endif
--
2.13.6