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Diffstat (limited to 'arch/powerpc/kernel/trace/ftrace_64_pg_entry.S')
-rw-r--r--arch/powerpc/kernel/trace/ftrace_64_pg_entry.S132
1 files changed, 132 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/trace/ftrace_64_pg_entry.S b/arch/powerpc/kernel/trace/ftrace_64_pg_entry.S
new file mode 100644
index 000000000000..a8a7f28404c8
--- /dev/null
+++ b/arch/powerpc/kernel/trace/ftrace_64_pg_entry.S
@@ -0,0 +1,132 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Split from ftrace_64.S
+ */
+
+#include <linux/export.h>
+#include <linux/magic.h>
+#include <asm/ppc_asm.h>
+#include <asm/asm-offsets.h>
+#include <asm/ftrace.h>
+#include <asm/ppc-opcode.h>
+
+_GLOBAL_TOC(ftrace_caller)
+ lbz r3, PACA_FTRACE_ENABLED(r13)
+ cmpdi r3, 0
+ beqlr
+
+ /* Taken from output of objdump from lib64/glibc */
+ mflr r3
+ ld r11, 0(r1)
+ stdu r1, -112(r1)
+ std r3, 128(r1)
+ ld r4, 16(r11)
+ subi r3, r3, MCOUNT_INSN_SIZE
+.globl ftrace_call
+ftrace_call:
+ bl ftrace_stub
+ nop
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+.globl ftrace_graph_call
+ftrace_graph_call:
+ b ftrace_graph_stub
+_GLOBAL(ftrace_graph_stub)
+#endif
+ ld r0, 128(r1)
+ mtlr r0
+ addi r1, r1, 112
+
+_GLOBAL(ftrace_stub)
+ blr
+
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+_GLOBAL(ftrace_graph_caller)
+ addi r5, r1, 112
+ /* load r4 with local address */
+ ld r4, 128(r1)
+ subi r4, r4, MCOUNT_INSN_SIZE
+
+ /* Grab the LR out of the caller stack frame */
+ ld r11, 112(r1)
+ ld r3, 16(r11)
+
+ bl prepare_ftrace_return
+ nop
+
+ /*
+ * prepare_ftrace_return gives us the address we divert to.
+ * Change the LR in the callers stack frame to this.
+ */
+ ld r11, 112(r1)
+ std r3, 16(r11)
+
+ ld r0, 128(r1)
+ mtlr r0
+ addi r1, r1, 112
+ blr
+#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
+
+.pushsection ".tramp.ftrace.text","aw",@progbits;
+.globl ftrace_tramp_text
+ftrace_tramp_text:
+ .space 32
+.popsection
+
+.pushsection ".tramp.ftrace.init","aw",@progbits;
+.globl ftrace_tramp_init
+ftrace_tramp_init:
+ .space 32
+.popsection
+
+_GLOBAL(mcount)
+_GLOBAL(_mcount)
+EXPORT_SYMBOL(_mcount)
+ mflr r12
+ mtctr r12
+ mtlr r0
+ bctr
+
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+_GLOBAL(return_to_handler)
+ /* need to save return values */
+#ifdef CONFIG_PPC64
+ std r4, -32(r1)
+ std r3, -24(r1)
+ /* save TOC */
+ std r2, -16(r1)
+ std r31, -8(r1)
+ mr r31, r1
+ stdu r1, -112(r1)
+
+ /*
+ * We might be called from a module.
+ * Switch to our TOC to run inside the core kernel.
+ */
+ LOAD_PACA_TOC()
+#else
+ stwu r1, -16(r1)
+ stw r3, 8(r1)
+ stw r4, 12(r1)
+#endif
+
+ bl ftrace_return_to_handler
+ nop
+
+ /* return value has real return address */
+ mtlr r3
+
+#ifdef CONFIG_PPC64
+ ld r1, 0(r1)
+ ld r4, -32(r1)
+ ld r3, -24(r1)
+ ld r2, -16(r1)
+ ld r31, -8(r1)
+#else
+ lwz r3, 8(r1)
+ lwz r4, 12(r1)
+ addi r1, r1, 16
+#endif
+
+ /* Jump back to real return address */
+ blr
+#endif /* CONFIG_FUNCTION_GRAPH_TRACER */