[PATCH 6/7] powerpc/watchpoint: Return available watchpoints dynamically

From: Ravi Bangoria
Date: Tue Jun 02 2020 - 00:02:20 EST


So far Book3S Powerpc supported only one watchpoint. But Power10 is
introducing 2nd DAWR. Enable 2nd DAWR support for Power10. Availability
of 2nd DAWR will depend on CPU_FTR_DAWR1.

Signed-off-by: Ravi Bangoria <ravi.bangoria@xxxxxxxxxxxxx>
---
arch/powerpc/include/asm/cputable.h | 4 +++-
arch/powerpc/include/asm/hw_breakpoint.h | 5 +++--
2 files changed, 6 insertions(+), 3 deletions(-)

diff --git a/arch/powerpc/include/asm/cputable.h b/arch/powerpc/include/asm/cputable.h
index 3445c86e1f6f..f110f70a11bf 100644
--- a/arch/powerpc/include/asm/cputable.h
+++ b/arch/powerpc/include/asm/cputable.h
@@ -633,7 +633,9 @@ enum {
* Maximum number of hw breakpoint supported on powerpc. Number of
* breakpoints supported by actual hw might be less than this.
*/
-#define HBP_NUM_MAX 1
+#define HBP_NUM_MAX 2
+#define HBP_NUM_P7_TO_P9 1
+#define HBP_NUM_P10 2

#endif /* !__ASSEMBLY__ */

diff --git a/arch/powerpc/include/asm/hw_breakpoint.h b/arch/powerpc/include/asm/hw_breakpoint.h
index f42a55eb77d2..0365a137d6e8 100644
--- a/arch/powerpc/include/asm/hw_breakpoint.h
+++ b/arch/powerpc/include/asm/hw_breakpoint.h
@@ -5,10 +5,11 @@
* Copyright 2010, IBM Corporation.
* Author: K.Prasad <prasad@xxxxxxxxxxxxxxxxxx>
*/
-
#ifndef _PPC_BOOK3S_64_HW_BREAKPOINT_H
#define _PPC_BOOK3S_64_HW_BREAKPOINT_H

+#include <asm/cpu_has_feature.h>
+
#ifdef __KERNEL__
struct arch_hw_breakpoint {
unsigned long address;
@@ -46,7 +47,7 @@ struct arch_hw_breakpoint {

static inline int nr_wp_slots(void)
{
- return HBP_NUM_MAX;
+ return cpu_has_feature(CPU_FTR_DAWR1) ? HBP_NUM_P10 : HBP_NUM_P7_TO_P9;
}

#ifdef CONFIG_HAVE_HW_BREAKPOINT
--
2.26.2