[PATCH 5/9][v5] powerpc: implement is_instr_load_store().

Sukadev Bhattiprolu
2013-10-02T00:15:55Z

Implement is_instr_load_store() to detect whether a given instruction
is one of the fixed-point or floating-point load/store instructions.
This function will be used in a follow-on patch to save memory hierarchy
information of the load/store.

Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Reviewed-by: Anshuman Khandual <khandual@linux.vnet.ibm.com>
---
arch/powerpc/include/asm/code-patching.h | 1 +
arch/powerpc/lib/code-patching.c | 90 ++++++++++++++++++++++++++++++
2 files changed, 91 insertions(+)

diff --git a/arch/powerpc/include/asm/code-patching.h b/arch/powerpc/include/asm/code-patching.h
index a6f8c7a..3e47fe0 100644
--- a/arch/powerpc/include/asm/code-patching.h
+++ b/arch/powerpc/include/asm/code-patching.h
@@ -34,6 +34,7 @@ int instr_is_branch_to_addr(const unsigned int *instr, unsigned long addr);
unsigned long branch_target(const unsigned int *instr);
unsigned int translate_branch(const unsigned int *dest,
const unsigned int *src);
+int instr_is_load_store(const unsigned int *instr);

static inline unsigned long ppc_function_entry(void *func)
{
diff --git a/arch/powerpc/lib/code-patching.c b/arch/powerpc/lib/code-patching.c
index 2bc9db3..7e5dc6f 100644
--- a/arch/powerpc/lib/code-patching.c
+++ b/arch/powerpc/lib/code-patching.c
@@ -159,6 +159,96 @@ unsigned int translate_branch(const unsigned int *dest, const unsigned int *src)
return 0;
}

+static unsigned int load_store_xval(const unsigned int instr)
+{
+ return (instr >> 1) & 0x3FF; /* bits 21..30 */
+}
+
+/*
+ * Values of bits 21:30 of Fixed-point and Floating-point Load and Store
+ * instructions.
+ *
+ * Reference: PowerISA_V2.06B_Public.pdf, Sections 3.3.2 through 3.3.6 and
+ * 4.6.2 through 4.6.4.
+ */
+#define x_lbzx 87
+#define x_lbzux 119
+#define x_lhzx 279
+#define x_lhzux 311
+#define x_lhax 343
+#define x_lhaux 375
+#define x_lwzx 23
+#define x_lwzux 55
+#define x_lwax 341
+#define x_lwaux 373
+#define x_ldx 21
+#define x_ldux 53
+#define x_stbx 215
+#define x_stbux 247
+#define x_sthx 407
+#define x_sthux 439
+#define x_stwx 151
+#define x_stwux 183
+#define x_stdx 149
+#define x_stdux 181
+#define x_lhbrx 790
+#define x_lwbrx 534
+#define x_sthbrx 918
+#define x_stwbrx 662
+#define x_ldbrx 532
+#define x_stdbrx 660
+#define x_lswi 597
+#define x_lswx 533
+#define x_stswi 725
+#define x_stswx 661
+#define x_lfsx 535
+#define x_lfsux 567
+#define x_lfdx 599
+#define x_lfdux 631
+#define x_lfiwax 855
+#define x_lfiwzx 887
+#define x_stfsx 663
+#define x_stfsux 695
+#define x_stfdx 727
+#define x_stfdux 759
+#define x_stfiwax 983
+#define x_lfdpx 791
+#define x_stfdpx 919
+
+static unsigned int x_form_load_store[] = {
+ x_lbzx, x_lbzux, x_lhzx, x_lhzux, x_lhax,
+ x_lhaux, x_lwzx, x_lwzux, x_lwax, x_lwaux,
+ x_ldx, x_ldux, x_stbx, x_stbux, x_sthx,
+ x_sthux, x_stwx, x_stwux, x_stdx, x_stdux,
+ x_lhbrx, x_lwbrx, x_sthbrx, x_stwbrx, x_ldbrx,
+ x_stdbrx, x_lswi, x_lswx, x_stswi, x_stswx,
+ x_lfsx, x_lfsux, x_lfdx, x_lfdux, x_lfiwax,
+ x_lfiwzx, x_stfsx, x_stfsux, x_stfdx, x_stfdux,
+ x_stfiwax, x_lfdpx, x_stfdpx
+};
+
+int instr_is_load_store(const unsigned int *instr)
+{
+ unsigned int op;
+ int i, n;
+
+ op = instr_opcode(*instr);
+
+ if ((op >= 32 && op <= 58) || (op == 61 || op == 62))
+ return 1;
+
+ if (op == 31) {
+ n = sizeof(x_form_load_store) / sizeof(int);
+
+ for (i = 0; i < n; i++) {
+ if (x_form_load_store[i] == load_store_xval(*instr))
+ return 1;
+ }
+ }
+
+ return 0;
+}
+

#ifdef CONFIG_CODE_PATCHING_SELFTEST

--
1.7.9.5