Patchwork arch/powerpc: advertise ISA2.07, HTM, DSCR, EBB and ISEL bits in HWCAP2

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Submitter Michael R Meissner
Date May 3, 2013, 11:26 p.m.
Message ID <OFFA9C9591.71B67D7B-ON85257B60.00808C43-85257B60.0080BB77@us.ibm.com>
Download mbox | patch
Permalink /patch/241420/
State Superseded
Headers show

Comments

Michael R Meissner - May 3, 2013, 11:26 p.m.
According to the GCC sources, ISEL is enabled by default for the 8540, 
8548, e500mc, e500mc64, e6500 processors.



From:
Nishanth Aravamudan <nacc@linux.vnet.ibm.com>
To:
benh@kernel.crashing.org, 
Cc:
Steve Munroe/Rochester/IBM@IBMUS, Peter Bergner/Rochester/IBM@IBMUS, 
Michael R Meissner/Cambridge/IBM@IBMUS, Michael Neuling 
<michael.neuling@au1.ibm.com>, linuxppc-dev@lists.ozlabs.org, Ryan 
Arnold/Rochester/IBM@IBMUS
Date:
05/03/2013 07:19 PM
Subject:
[PATCH] arch/powerpc: advertise ISA2.07, HTM, DSCR, EBB and ISEL bits in 
HWCAP2



Now that we have AT_HWCAP2 support, start exposing some of the new
POWER8 features via it.

Signed-off-by: Nishanth Aravamudan <nacc@us.ibm.com>

---
Note: there are, I think, some Freescale processors that also should be
updated to indicate they support ISEL, but I don't know which ones.
Since this is a new feature bit (and vector), it seems like we can fix
that up in a follow-on patch. Also, this is my first patch trying to
manipulate these bits, so please let me know if I'm doing something
wrong (for instance, I don't see any particular order to the bits in
PPC_FEATURE_*)

 PPC_FEATURE_TRUE_LE | \
 PPC_FEATURE_HAS_ALTIVEC_COMP)
@@ -443,6 +446,7 @@ static struct cpu_spec __initdata cpu_specs[] = {
                                 .cpu_name                               = 
"POWER8 (architected)",
                                 .cpu_features                           = 
CPU_FTRS_POWER8,
                                 .cpu_user_features              = 
COMMON_USER_POWER8,
+                                .cpu_user_features2             = 
COMMON_USER2_POWER8,
                                 .mmu_features                           = 
MMU_FTRS_POWER8,
                                 .icache_bsize                           = 
128,
                                 .dcache_bsize                           = 
128,
@@ -492,6 +496,7 @@ static struct cpu_spec __initdata cpu_specs[] = {
                                 .cpu_name                               = 
"POWER8 (raw)",
                                 .cpu_features                           = 
CPU_FTRS_POWER8,
                                 .cpu_user_features              = 
COMMON_USER_POWER8,
+                                .cpu_user_features2             = 
COMMON_USER2_POWER8,
                                 .mmu_features                           = 
MMU_FTRS_POWER8,
                                 .icache_bsize                           = 
128,
                                 .dcache_bsize                           = 
128,
Segher Boessenkool - May 4, 2013, 9:42 p.m.
> According to the GCC sources, ISEL is enabled by default for the  
> 8540, 8548, e500mc, e500mc64, e6500 processors.

And e5500.  POWER7 is said to support it as well.


Segher

Patch

diff --git a/arch/powerpc/include/uapi/asm/cputable.h 
b/arch/powerpc/include/uapi/asm/cputable.h
index ed9dd81..78db4e2 100644
--- a/arch/powerpc/include/uapi/asm/cputable.h
+++ b/arch/powerpc/include/uapi/asm/cputable.h
@@ -1,6 +1,7 @@ 
 #ifndef _UAPI__ASM_POWERPC_CPUTABLE_H
 #define _UAPI__ASM_POWERPC_CPUTABLE_H
 
+/* in AT_HWCAP */
 #define PPC_FEATURE_32 0x80000000
 #define PPC_FEATURE_64 0x40000000
 #define PPC_FEATURE_601_INSTR                           0x20000000
@@ -33,4 +34,11 @@ 
 #define PPC_FEATURE_TRUE_LE                             0x00000002
 #define PPC_FEATURE_PPC_LE                              0x00000001
 
+/* in AT_HWCAP2 */
+#define PPC_FEATURE2_ARCH_2_07                          0x80000000
+#define PPC_FEATURE2_HTM                                0x40000000
+#define PPC_FEATURE2_DSCR                               0x20000000
+#define PPC_FEATURE2_EBB                                0x10000000
+#define PPC_FEATURE2_ISEL                               0x08000000
+
 #endif /* _UAPI__ASM_POWERPC_CPUTABLE_H */
diff --git a/arch/powerpc/kernel/cputable.c 
b/arch/powerpc/kernel/cputable.c
index ae9f433..871c741 100644
--- a/arch/powerpc/kernel/cputable.c
+++ b/arch/powerpc/kernel/cputable.c
@@ -102,6 +102,9 @@  extern void __restore_cpu_e6500(void);
 PPC_FEATURE_SMT | PPC_FEATURE_ICACHE_SNOOP | \
 PPC_FEATURE_TRUE_LE | \
 PPC_FEATURE_PSERIES_PERFMON_COMPAT)
+#define COMMON_USER2_POWER8             (PPC_FEATURE2_ARCH_2_07 | 
PPC_FEATURE2_HTM | \
+ PPC_FEATURE2_DSCR | PPC_FEATURE2_EBB | \
+ PPC_FEATURE2_ISEL)
 #define COMMON_USER_PA6T                (COMMON_USER_PPC64 | 
PPC_FEATURE_PA6T |\