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-rw-r--r--arch/powerpc/kernel/vdso/datapage.S64
1 files changed, 64 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/vdso/datapage.S b/arch/powerpc/kernel/vdso/datapage.S
new file mode 100644
index 000000000..db8e167f0
--- /dev/null
+++ b/arch/powerpc/kernel/vdso/datapage.S
@@ -0,0 +1,64 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Access to the shared data page by the vDSO & syscall map
+ *
+ * Copyright (C) 2004 Benjamin Herrenschmuidt (benh@kernel.crashing.org), IBM Corp.
+ */
+
+#include <asm/processor.h>
+#include <asm/ppc_asm.h>
+#include <asm/asm-offsets.h>
+#include <asm/unistd.h>
+#include <asm/vdso.h>
+#include <asm/vdso_datapage.h>
+
+ .text
+
+/*
+ * void *__kernel_get_syscall_map(unsigned int *syscall_count) ;
+ *
+ * returns a pointer to the syscall map. the map is agnostic to the
+ * size of "long", unlike kernel bitops, it stores bits from top to
+ * bottom so that memory actually contains a linear bitmap
+ * check for syscall N by testing bit (0x80000000 >> (N & 0x1f)) of
+ * 32 bits int at N >> 5.
+ */
+V_FUNCTION_BEGIN(__kernel_get_syscall_map)
+ .cfi_startproc
+ mflr r12
+ .cfi_register lr,r12
+ mr. r4,r3
+ get_datapage r3
+ mtlr r12
+#ifdef __powerpc64__
+ addi r3,r3,CFG_SYSCALL_MAP64
+#else
+ addi r3,r3,CFG_SYSCALL_MAP32
+#endif
+ crclr cr0*4+so
+ beqlr
+ li r0,NR_syscalls
+ stw r0,0(r4)
+ blr
+ .cfi_endproc
+V_FUNCTION_END(__kernel_get_syscall_map)
+
+/*
+ * void unsigned long long __kernel_get_tbfreq(void);
+ *
+ * returns the timebase frequency in HZ
+ */
+V_FUNCTION_BEGIN(__kernel_get_tbfreq)
+ .cfi_startproc
+ mflr r12
+ .cfi_register lr,r12
+ get_datapage r3
+#ifndef __powerpc64__
+ lwz r4,(CFG_TB_TICKS_PER_SEC + 4)(r3)
+#endif
+ PPC_LL r3,CFG_TB_TICKS_PER_SEC(r3)
+ mtlr r12
+ crclr cr0*4+so
+ blr
+ .cfi_endproc
+V_FUNCTION_END(__kernel_get_tbfreq)