Export basic HWCAP bits to let applications detect Altivec on powerpc

Input from miod@ and gkoehler@, tests & ok gkoehler@

diff --git a/sys/arch/macppc/macppc/cpu.c b/sys/arch/macppc/macppc/cpu.c
index f3dbe07..d5f776c 100644 (file)
--- a/sys/arch/macppc/macppc/cpu.c
+++ b/sys/arch/macppc/macppc/cpu.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: cpu.c,v 1.87 2023/10/24 13:20:10 claudio Exp $ */
+/*     $OpenBSD: cpu.c,v 1.88 2024/07/21 16:46:56 jca Exp $ */
 
 /*
  * Copyright (c) 1997 Per Fogelstrom
@@ -48,6 +48,7 @@
 #include <powerpc/bat.h>
 #include <machine/cpu.h>
 #include <machine/trap.h>
+#include <machine/elf.h>
 #include <powerpc/hid.h>
 
 /* SCOM addresses (24-bit) */
@@ -201,6 +202,8 @@ cpuattach(struct device *parent, struct device *dev, void *aux)
        ci->ci_intrdepth = -1;
        ci->ci_dev = dev;
 
+       hwcap = PPC_FEATURE_32 | PPC_FEATURE_HAS_FPU | PPC_FEATURE_HAS_MMU;
+
        pvr = ppc_mfpvr();
        cpu = pvr >> 16;
        switch (cpu) {
@@ -278,6 +281,9 @@ cpuattach(struct device *parent, struct device *dev, void *aux)
 #ifndef ALTIVEC                        /* altivec support absent from kernel */
        ppc_altivec = 0;
 #endif
+       if (ppc_altivec)
+               hwcap |= PPC_FEATURE_HAS_ALTIVEC;
+
        snprintf(cpu_model + strlen(cpu_model),
            sizeof(cpu_model) - strlen(cpu_model),
            " (Revision 0x%x)", pvr & 0xffff);

diff --git a/sys/arch/powerpc/include/elf.h b/sys/arch/powerpc/include/elf.h
index 6624f42..73cda20 100644 (file)
--- a/sys/arch/powerpc/include/elf.h
+++ b/sys/arch/powerpc/include/elf.h
@@ -1,4 +1,4 @@
-/*     $OpenBSD: elf.h,v 1.1 2024/07/14 09:48:48 jca Exp $     */
+/*     $OpenBSD: elf.h,v 1.2 2024/07/21 16:46:57 jca Exp $     */
 
 /*
  * This file is in the public domain.
@@ -8,7 +8,57 @@
 #define        _MACHINE_ELF_H_
 
 /*
- * TODO FreeBSD puts PPC_FEATURE* in cpu.h
+ * CPU Feature Attributes
+ *
+ * These are defined in the PowerPC ELF ABI for the AT_HWCAP vector,
+ * and are exported to userland via the elf_aux_info(3) function.
  */
 
+#ifdef _KERNEL
+# define __HAVE_CPU_HWCAP
+# define __HAVE_CPU_HWCAP2
+extern unsigned long hwcap;
+extern unsigned long hwcap2;
+#endif /* _KERNEL */
+
+#define        PPC_FEATURE_32          0x80000000      /* Always true */
+#define        PPC_FEATURE_64          0x40000000      /* Defined on a 64-bit CPU */
+#define        PPC_FEATURE_601_INSTR   0x20000000
+#define        PPC_FEATURE_HAS_ALTIVEC 0x10000000
+#define        PPC_FEATURE_HAS_FPU     0x08000000
+#define        PPC_FEATURE_HAS_MMU     0x04000000
+#define        PPC_FEATURE_UNIFIED_CACHE 0x01000000
+#define        PPC_FEATURE_HAS_SPE     0x00800000
+#define        PPC_FEATURE_HAS_EFP_SINGLE      0x00400000
+#define        PPC_FEATURE_HAS_EFP_DOUBLE      0x00200000
+#define        PPC_FEATURE_NO_TB       0x00100000
+#define        PPC_FEATURE_POWER4      0x00080000
+#define        PPC_FEATURE_POWER5      0x00040000
+#define        PPC_FEATURE_POWER5_PLUS 0x00020000
+#define        PPC_FEATURE_CELL        0x00010000
+#define        PPC_FEATURE_BOOKE       0x00008000
+#define        PPC_FEATURE_SMT         0x00004000
+#define        PPC_FEATURE_ICACHE_SNOOP        0x00002000
+#define        PPC_FEATURE_ARCH_2_05   0x00001000
+#define        PPC_FEATURE_HAS_DFP     0x00000400
+#define        PPC_FEATURE_POWER6_EXT  0x00000200
+#define        PPC_FEATURE_ARCH_2_06   0x00000100
+#define        PPC_FEATURE_HAS_VSX     0x00000080
+#define        PPC_FEATURE_TRUE_LE     0x00000002
+#define        PPC_FEATURE_PPC_LE      0x00000001
+
+#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
+#define        PPC_FEATURE2_TAR        0x04000000
+#define        PPC_FEATURE2_HAS_VEC_CRYPTO     0x02000000
+#define        PPC_FEATURE2_HTM_NOSC   0x01000000
+#define        PPC_FEATURE2_ARCH_3_00  0x00800000
+#define        PPC_FEATURE2_HAS_IEEE128        0x00400000
+#define        PPC_FEATURE2_DARN       0x00200000
+#define        PPC_FEATURE2_SCV        0x00100000
+#define        PPC_FEATURE2_HTM_NOSUSPEND      0x00080000
+
 #endif /* !_MACHINE_ELF_H_ */