powerpc/sstep: Add tests for prefixed floating-point load/stores

Add tests for the prefixed versions of the floating-point load/stores
that are currently tested. This includes the following instructions:
  * Prefixed Load Floating-Point Single (plfs)
  * Prefixed Load Floating-Point Double (plfd)
  * Prefixed Store Floating-Point Single (pstfs)
  * Prefixed Store Floating-Point Double (pstfd)

Skip the new tests if ISA v3.10 is unsupported.

Signed-off-by: Jordan Niethe <jniethe5@gmail.com>
[mpe: Fix conflicts with ppc-opcode.h changes]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200525025923.19843-2-jniethe5@gmail.com

arch/powerpc/include/asm/ppc-opcode.h

@@ -266,6 +266,10 @@
 #define PPC_INST_BRANCH_COND		0x40800000
 
 /* Prefixes */
+#define PPC_INST_LFS			0xc0000000
+#define PPC_INST_STFS			0xd0000000
+#define PPC_INST_LFD			0xc8000000
+#define PPC_INST_STFD			0xd8000000
 #define PPC_PREFIX_MLS			0x06000000
 #define PPC_PREFIX_8LS			0x04000000
 

arch/powerpc/lib/test_emulate_step.c

@@ -31,6 +31,22 @@
 	ppc_inst_prefix(PPC_PREFIX_8LS | __PPC_PRFX_R(pr) | IMM_H(i), \
 			PPC_INST_PSTD | ___PPC_RT(r) | ___PPC_RA(base) | IMM_L(i))
 
+#define TEST_PLFS(r, base, i, pr) \
+	ppc_inst_prefix(PPC_PREFIX_MLS | __PPC_PRFX_R(pr) | IMM_H(i), \
+			PPC_INST_LFS | ___PPC_RT(r) | ___PPC_RA(base) | IMM_L(i))
+
+#define TEST_PSTFS(r, base, i, pr) \
+	ppc_inst_prefix(PPC_PREFIX_MLS | __PPC_PRFX_R(pr) | IMM_H(i), \
+			PPC_INST_STFS | ___PPC_RT(r) | ___PPC_RA(base) | IMM_L(i))
+
+#define TEST_PLFD(r, base, i, pr) \
+	ppc_inst_prefix(PPC_PREFIX_MLS | __PPC_PRFX_R(pr) | IMM_H(i), \
+			PPC_INST_LFD | ___PPC_RT(r) | ___PPC_RA(base) | IMM_L(i))
+
+#define TEST_PSTFD(r, base, i, pr) \
+	ppc_inst_prefix(PPC_PREFIX_MLS | __PPC_PRFX_R(pr) | IMM_H(i), \
+			PPC_INST_STFD | ___PPC_RT(r) | ___PPC_RA(base) | IMM_L(i))
+
 static void __init init_pt_regs(struct pt_regs *regs)
 {
 	static unsigned long msr;
@@ -304,6 +320,53 @@ static void __init test_lfsx_stfsx(void)
 		show_result("stfsx", "FAIL");
 }
 
+static void __init test_plfs_pstfs(void)
+{
+	struct pt_regs regs;
+	union {
+		float a;
+		int b;
+	} c;
+	int cached_b;
+	int stepped = -1;
+
+	if (!cpu_has_feature(CPU_FTR_ARCH_31)) {
+		show_result("pld", "SKIP (!CPU_FTR_ARCH_31)");
+		return;
+	}
+
+	init_pt_regs(&regs);
+
+
+	/*** plfs ***/
+
+	c.a = 123.45;
+	cached_b = c.b;
+
+	regs.gpr[3] = (unsigned long)&c.a;
+
+	/* plfs frt10, 0(r3), 0  */
+	stepped = emulate_step(&regs, TEST_PLFS(10, 3, 0, 0));
+
+	if (stepped == 1)
+		show_result("plfs", "PASS");
+	else
+		show_result("plfs", "FAIL");
+
+
+	/*** pstfs ***/
+
+	c.a = 678.91;
+
+	/* pstfs frs10, 0(r3), 0 */
+	stepped = emulate_step(&regs, TEST_PSTFS(10, 3, 0, 0));
+
+	if (stepped == 1 && c.b == cached_b)
+		show_result("pstfs", "PASS");
+	else
+		show_result("pstfs", "FAIL");
+}
+
 static void __init test_lfdx_stfdx(void)
 {
 	struct pt_regs regs;
@@ -346,6 +409,53 @@ static void __init test_lfdx_stfdx(void)
 	else
 		show_result("stfdx", "FAIL");
 }
+
+static void __init test_plfd_pstfd(void)
+{
+	struct pt_regs regs;
+	union {
+		double a;
+		long b;
+	} c;
+	long cached_b;
+	int stepped = -1;
+
+	if (!cpu_has_feature(CPU_FTR_ARCH_31)) {
+		show_result("pld", "SKIP (!CPU_FTR_ARCH_31)");
+		return;
+	}
+
+	init_pt_regs(&regs);
+
+
+	/*** plfd ***/
+
+	c.a = 123456.78;
+	cached_b = c.b;
+
+	regs.gpr[3] = (unsigned long)&c.a;
+
+	/* plfd frt10, 0(r3), 0 */
+	stepped = emulate_step(&regs, TEST_PLFD(10, 3, 0, 0));
+
+	if (stepped == 1)
+		show_result("plfd", "PASS");
+	else
+		show_result("plfd", "FAIL");
+
+
+	/*** pstfd ***/
+
+	c.a = 987654.32;
+
+	/* pstfd frs10, 0(r3), 0 */
+	stepped = emulate_step(&regs, TEST_PSTFD(10, 3, 0, 0));
+
+	if (stepped == 1 && c.b == cached_b)
+		show_result("pstfd", "PASS");
+	else
+		show_result("pstfd", "FAIL");
+}
 #else
 static void __init test_lfsx_stfsx(void)
 {
@@ -353,11 +463,23 @@ static void __init test_lfsx_stfsx(void)
 	show_result("stfsx", "SKIP (CONFIG_PPC_FPU is not set)");
 }
 
+static void __init test_plfs_pstfs(void)
+{
+	show_result("plfs", "SKIP (CONFIG_PPC_FPU is not set)");
+	show_result("pstfs", "SKIP (CONFIG_PPC_FPU is not set)");
+}
+
 static void __init test_lfdx_stfdx(void)
 {
 	show_result("lfdx", "SKIP (CONFIG_PPC_FPU is not set)");
 	show_result("stfdx", "SKIP (CONFIG_PPC_FPU is not set)");
 }
+
+static void __init test_plfd_pstfd(void)
+{
+	show_result("plfd", "SKIP (CONFIG_PPC_FPU is not set)");
+	show_result("pstfd", "SKIP (CONFIG_PPC_FPU is not set)");
+}
 #endif /* CONFIG_PPC_FPU */
 
 #ifdef CONFIG_ALTIVEC
@@ -494,7 +616,9 @@ static void __init run_tests_load_store(void)
 	test_pstd();
 	test_ldarx_stdcx();
 	test_lfsx_stfsx();
+	test_plfs_pstfs();
 	test_lfdx_stfdx();
+	test_plfd_pstfd();
 	test_lvx_stvx();
 	test_lxvd2x_stxvd2x();
 }