[PW_SID:1081067] riscv32 library enhancements and build fixes

arch/riscv/Kconfig

@@ -407,9 +407,6 @@ config ARCH_RV32I
 	bool "RV32I"
 	depends on NONPORTABLE
 	select 32BIT
-	select GENERIC_LIB_ASHLDI3
-	select GENERIC_LIB_ASHRDI3
-	select GENERIC_LIB_LSHRDI3
 	select GENERIC_LIB_UCMPDI2
 
 config ARCH_RV64I

arch/riscv/kernel/image-vars.h

@@ -32,6 +32,13 @@ __efistub___init_text_end	= __init_text_end;
 __efistub_sysfb_primary_display	= sysfb_primary_display;
 #endif
 
+/*
+ * These double-word integer shifts are used
+ * by the library code and so EFI stub as well.
+ */
+PROVIDE(__efistub___lshrdi3    = __lshrdi3);
+PROVIDE(__efistub___ashldi3    = __ashldi3);
+
 #endif
 
 #endif /* __RISCV_KERNEL_IMAGE_VARS_H */

arch/riscv/lib/Makefile

@@ -13,6 +13,7 @@ ifeq ($(CONFIG_MMU), y)
 lib-$(CONFIG_RISCV_ISA_V)	+= uaccess_vector.o
 endif
 lib-$(CONFIG_MMU)	+= uaccess.o
+lib-$(CONFIG_32BIT)	+= ashldi3.o ashrdi3.o lshrdi3.o
 lib-$(CONFIG_64BIT)	+= tishift.o
 lib-$(CONFIG_RISCV_ISA_ZICBOZ)	+= clear_page.o
 obj-$(CONFIG_FUNCTION_ERROR_INJECTION) += error-inject.o

arch/riscv/lib/ashldi3.S

@@ -0,0 +1,36 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/**
+ * Adopted for the Linux kernel from IPXE project, see
+ * https://github.com/ipxe/ipxe/blob/master/src/arch/riscv32/libgcc/llshift.S
+ */
+
+#include <linux/linkage.h>
+#include <asm/asm.h>
+
+/**
+ * Shift left
+ *
+ * @v a1:a0             Value to shift
+ * @v a2                Shift amount
+ * @ret a1:a0           Shifted value
+ */
+
+SYM_FUNC_START(__ashldi3)
+
+        /* Perform shift by 32 bits, if applicable */
+        li      t0, 32
+        sub     t1, t0, a2
+        bgtz    t1, 1f
+        mv      a1, a0
+        mv      a0, zero
+1:      /* Perform shift by modulo-32 bits, if applicable */
+        andi    a2, a2, 0x1f
+        beqz    a2, 2f
+        srl     t2, a0, t1
+        sll     a0, a0, a2
+        sll     a1, a1, a2
+        or      a1, a1, t2
+2:      ret
+
+SYM_FUNC_END(__ashldi3)
+EXPORT_SYMBOL(__ashldi3)

arch/riscv/lib/ashrdi3.S

@@ -0,0 +1,37 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/**
+ * Adopted for the Linux kernel from IPXE project, see
+ * https://github.com/ipxe/ipxe/blob/master/src/arch/riscv32/libgcc/llshift.S
+ */
+
+#include <linux/linkage.h>
+#include <asm/asm.h>
+
+/**
+ * Arithmetic shift right
+ *
+ * @v a1:a0             Value to shift
+ * @v a2                Shift amount
+ * @ret a1:a0           Shifted value
+ */
+
+SYM_FUNC_START(__ashrdi3)
+
+        /* Perform shift by 32 bits, if applicable */
+        li      t0, 32
+        sub     t1, t0, a2
+        bgtz    t1, 1f
+        mv      a0, a1
+        srai    a1, a1, 16
+        srai    a1, a1, 16
+1:      /* Perform shift by modulo-32 bits, if applicable */
+        andi    a2, a2, 0x1f
+        beqz    a2, 2f
+        sll     t2, a1, t1
+        sra     a1, a1, a2
+        srl     a0, a0, a2
+        or      a0, a0, t2
+2:      ret
+
+SYM_FUNC_END(__ashrdi3)
+EXPORT_SYMBOL(__ashrdi3)

arch/riscv/lib/lshrdi3.S

@@ -0,0 +1,36 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/**
+ * Adopted for the Linux kernel from IPXE project, see
+ * https://github.com/ipxe/ipxe/blob/master/src/arch/riscv32/libgcc/llshift.S
+ */
+
+#include <linux/linkage.h>
+#include <asm/asm.h>
+
+/**
+ * Logical shift right
+ *
+ * @v a1:a0             Value to shift
+ * @v a2                Shift amount
+ * @ret a1:a0           Shifted value
+ */
+
+SYM_FUNC_START(__lshrdi3)
+
+        /* Perform shift by 32 bits, if applicable */
+        li      t0, 32
+        sub     t1, t0, a2
+        bgtz    t1, 1f
+        mv      a0, a1
+        mv      a1, zero
+1:      /* Perform shift by modulo-32 bits, if applicable */
+        andi    a2, a2, 0x1f
+        beqz    a2, 2f
+        sll     t2, a1, t1
+        srl     a1, a1, a2
+        srl     a0, a0, a2
+        or      a0, a0, t2
+2:      ret
+
+SYM_FUNC_END(__lshrdi3)
+EXPORT_SYMBOL(__lshrdi3)

drivers/firmware/efi/Kconfig

@@ -85,6 +85,10 @@ config EFI_ZBOOT
 	  provided that the loader implements the decompression algorithm.
 	  (The compression algorithm used is described in the zboot header)
 
+config EFI_ZBOOT_USE_LIBGCC
+	bool
+	default y if RISCV && 32BIT
+
 config EFI_ARMSTUB_DTB_LOADER
 	bool "Enable the DTB loader"
 	depends on EFI_GENERIC_STUB && !RISCV && !LOONGARCH

drivers/firmware/efi/libstub/Makefile

@@ -96,7 +96,8 @@ CFLAGS_zboot-decompress-gzip.o	+= -I$(srctree)/lib/zlib_inflate
 zboot-obj-$(CONFIG_KERNEL_ZSTD)	:= zboot-decompress-zstd.o lib-xxhash.o
 CFLAGS_zboot-decompress-zstd.o	+= -I$(srctree)/lib/zstd
 
-zboot-obj-$(CONFIG_RISCV)	+= lib-clz_ctz.o lib-ashldi3.o
+zboot-libgcc-obj-$(CONFIG_EFI_ZBOOT_USE_LIBGCC) += lib-ashldi3.o lib-lshrdi3.o
+zboot-obj-$(CONFIG_RISCV)	+= lib-clz_ctz.o $(zboot-libgcc-obj-y)
 lib-$(CONFIG_EFI_ZBOOT)		+= zboot.o $(zboot-obj-y)
 
 lib-$(CONFIG_UNACCEPTED_MEMORY) += unaccepted_memory.o bitmap.o find.o

lib/Kconfig.debug

@@ -2942,6 +2942,16 @@ config BITS_TEST
 
 	  If unsure, say N.
 
+config SHDI3_KUNIT_TEST
+	tristate "KUnit test for __ashldi3(), __ashrdi3(), and __lshrdi3()"
+	depends on KUNIT
+	depends on (32BIT || ARM)
+	help
+	  This builds the unit test for __ashldi3(), __ashrdi3(), and
+	  __lshrdi3() helper functions used to implement 64-bit arithmetic
+	  shift left, arithmetic shift right and logical shift right,
+	  respectively, on a 32-bit CPUs.
+
 config SLUB_KUNIT_TEST
 	tristate "KUnit test for SLUB cache error detection" if !KUNIT_ALL_TESTS
 	depends on SLUB_DEBUG && KUNIT

lib/tests/Makefile

@@ -8,6 +8,7 @@ obj-$(CONFIG_BASE64_KUNIT) += base64_kunit.o
 obj-$(CONFIG_BITOPS_KUNIT) += bitops_kunit.o
 obj-$(CONFIG_BITFIELD_KUNIT) += bitfield_kunit.o
 obj-$(CONFIG_BITS_TEST) += test_bits.o
+obj-$(CONFIG_SHDI3_KUNIT_TEST) += shdi3_kunit.o
 obj-$(CONFIG_BLACKHOLE_DEV_KUNIT_TEST) += blackhole_dev_kunit.o
 obj-$(CONFIG_CHECKSUM_KUNIT) += checksum_kunit.o
 obj-$(CONFIG_CMDLINE_KUNIT_TEST) += cmdline_kunit.o

lib/tests/shdi3_kunit.c

@@ -0,0 +1,175 @@
+// SPDX-License-Identifier: GPL-2.0-or-later OR Apache-2.0
+/*
+ * Test cases for __ashldi3(), __ashrdi3(), and __lshrdi3().
+ */
+
+#include <linux/array_size.h>
+#include <linux/module.h>
+#include <linux/libgcc.h>
+#include <kunit/test.h>
+
+struct shdi3_test_entry {
+	long long input;
+	int shift;
+	long long result;
+};
+
+static const struct shdi3_test_entry ashldi3_testdata[] = {
+	/* https://github.com/llvm/llvm-project/compiler-rt/test/builtins/Unit/ashldi3_test.c */
+	{ 0x0123456789ABCDEFLL, 0, 0x123456789ABCDEFLL },
+	{ 0x0123456789ABCDEFLL, 1, 0x2468ACF13579BDELL },
+	{ 0x0123456789ABCDEFLL, 2, 0x48D159E26AF37BCLL },
+	{ 0x0123456789ABCDEFLL, 3, 0x91A2B3C4D5E6F78LL },
+	{ 0x0123456789ABCDEFLL, 4, 0x123456789ABCDEF0LL },
+	{ 0x0123456789ABCDEFLL, 28, 0x789ABCDEF0000000LL },
+	{ 0x0123456789ABCDEFLL, 29, 0xF13579BDE0000000LL },
+	{ 0x0123456789ABCDEFLL, 30, 0xE26AF37BC0000000LL },
+	{ 0x0123456789ABCDEFLL, 31, 0xC4D5E6F780000000LL },
+	{ 0x0123456789ABCDEFLL, 32, 0x89ABCDEF00000000LL },
+	{ 0x0123456789ABCDEFLL, 33, 0x13579BDE00000000LL },
+	{ 0x0123456789ABCDEFLL, 34, 0x26AF37BC00000000LL },
+	{ 0x0123456789ABCDEFLL, 35, 0x4D5E6F7800000000LL },
+	{ 0x0123456789ABCDEFLL, 36, 0x9ABCDEF000000000LL },
+	{ 0x0123456789ABCDEFLL, 60, 0xF000000000000000LL },
+	{ 0x0123456789ABCDEFLL, 61, 0xE000000000000000LL },
+	{ 0x0123456789ABCDEFLL, 62, 0xC000000000000000LL },
+	{ 0x0123456789ABCDEFLL, 63, 0x8000000000000000LL },
+};
+
+static void shdi3_test_ashldi3(struct kunit *test)
+{
+	const struct shdi3_test_entry *e;
+	long long ret;
+
+	for (e = ashldi3_testdata;
+	     e < ashldi3_testdata + ARRAY_SIZE(ashldi3_testdata); e++) {
+		ret = __ashldi3(e->input, e->shift);
+		KUNIT_EXPECT_EQ_MSG(test, ret, e->result,
+				    "    when evaluating __ashldi3(%lld, %d)",
+				    e->input, e->shift);
+	}
+}
+
+static const struct shdi3_test_entry ashrdi3_testdata[] = {
+	/* https://github.com/llvm/llvm-project/compiler-rt/test/builtins/Unit/ashrdi3_test.c */
+	{ 0x0123456789ABCDEFLL, 0, 0x123456789ABCDEFLL },
+	{ 0x0123456789ABCDEFLL, 1, 0x91A2B3C4D5E6F7LL },
+	{ 0x0123456789ABCDEFLL, 2, 0x48D159E26AF37BLL },
+	{ 0x0123456789ABCDEFLL, 3, 0x2468ACF13579BDLL },
+	{ 0x0123456789ABCDEFLL, 4, 0x123456789ABCDELL },
+	{ 0x0123456789ABCDEFLL, 28, 0x12345678LL },
+	{ 0x0123456789ABCDEFLL, 29, 0x91A2B3CLL },
+	{ 0x0123456789ABCDEFLL, 30, 0x48D159ELL },
+	{ 0x0123456789ABCDEFLL, 31, 0x2468ACFLL },
+	{ 0x0123456789ABCDEFLL, 32, 0x1234567LL },
+	{ 0x0123456789ABCDEFLL, 33, 0x91A2B3LL },
+	{ 0x0123456789ABCDEFLL, 34, 0x48D159LL },
+	{ 0x0123456789ABCDEFLL, 35, 0x2468ACLL },
+	{ 0x0123456789ABCDEFLL, 36, 0x123456LL },
+	{ 0x0123456789ABCDEFLL, 60, 0 },
+	{ 0x0123456789ABCDEFLL, 61, 0 },
+	{ 0x0123456789ABCDEFLL, 62, 0 },
+	{ 0x0123456789ABCDEFLL, 63, 0 },
+	{ 0xFEDCBA9876543210LL, 0, 0xFEDCBA9876543210LL },
+	{ 0xFEDCBA9876543210LL, 1, 0xFF6E5D4C3B2A1908LL },
+	{ 0xFEDCBA9876543210LL, 2, 0xFFB72EA61D950C84LL },
+	{ 0xFEDCBA9876543210LL, 3, 0xFFDB97530ECA8642LL },
+	{ 0xFEDCBA9876543210LL, 4, 0xFFEDCBA987654321LL },
+	{ 0xFEDCBA9876543210LL, 28, 0xFFFFFFFFEDCBA987LL },
+	{ 0xFEDCBA9876543210LL, 29, 0xFFFFFFFFF6E5D4C3LL },
+	{ 0xFEDCBA9876543210LL, 30, 0xFFFFFFFFFB72EA61LL },
+	{ 0xFEDCBA9876543210LL, 31, 0xFFFFFFFFFDB97530LL },
+	{ 0xFEDCBA9876543210LL, 32, 0xFFFFFFFFFEDCBA98LL },
+	{ 0xFEDCBA9876543210LL, 33, 0xFFFFFFFFFF6E5D4CLL },
+	{ 0xFEDCBA9876543210LL, 34, 0xFFFFFFFFFFB72EA6LL },
+	{ 0xFEDCBA9876543210LL, 35, 0xFFFFFFFFFFDB9753LL },
+	{ 0xFEDCBA9876543210LL, 36, 0xFFFFFFFFFFEDCBA9LL },
+	{ 0xAEDCBA9876543210LL, 60, 0xFFFFFFFFFFFFFFFALL },
+	{ 0xAEDCBA9876543210LL, 61, 0xFFFFFFFFFFFFFFFDLL },
+	{ 0xAEDCBA9876543210LL, 62, 0xFFFFFFFFFFFFFFFELL },
+	{ 0xAEDCBA9876543210LL, 63, 0xFFFFFFFFFFFFFFFFLL },
+};
+
+static void shdi3_test_ashrdi3(struct kunit *test)
+{
+	const struct shdi3_test_entry *e;
+	long long ret;
+
+	for (e = ashrdi3_testdata;
+	     e < ashrdi3_testdata + ARRAY_SIZE(ashrdi3_testdata); e++) {
+		ret = __ashrdi3(e->input, e->shift);
+		KUNIT_EXPECT_EQ_MSG(test, ret, e->result,
+				    "    when evaluating __ashrdi3(%lld, %d)",
+				    e->input, e->shift);
+	}
+}
+
+static const struct shdi3_test_entry lshrdi3_testdata[] = {
+	/* https://github.com/llvm/llvm-project/compiler-rt/test/builtins/Unit/lshrdi3_test.c */
+	{ 0x0123456789ABCDEFLL, 0, 0x123456789ABCDEFLL },
+	{ 0x0123456789ABCDEFLL, 1, 0x91A2B3C4D5E6F7LL },
+	{ 0x0123456789ABCDEFLL, 2, 0x48D159E26AF37BLL },
+	{ 0x0123456789ABCDEFLL, 3, 0x2468ACF13579BDLL },
+	{ 0x0123456789ABCDEFLL, 4, 0x123456789ABCDELL },
+	{ 0x0123456789ABCDEFLL, 28, 0x12345678LL },
+	{ 0x0123456789ABCDEFLL, 29, 0x91A2B3CLL },
+	{ 0x0123456789ABCDEFLL, 30, 0x48D159ELL },
+	{ 0x0123456789ABCDEFLL, 31, 0x2468ACFLL },
+	{ 0x0123456789ABCDEFLL, 32, 0x1234567LL },
+	{ 0x0123456789ABCDEFLL, 33, 0x91A2B3LL },
+	{ 0x0123456789ABCDEFLL, 34, 0x48D159LL },
+	{ 0x0123456789ABCDEFLL, 35, 0x2468ACLL },
+	{ 0x0123456789ABCDEFLL, 36, 0x123456LL },
+	{ 0x0123456789ABCDEFLL, 60, 0 },
+	{ 0x0123456789ABCDEFLL, 61, 0 },
+	{ 0x0123456789ABCDEFLL, 62, 0 },
+	{ 0x0123456789ABCDEFLL, 63, 0 },
+	{ 0xFEDCBA9876543210LL, 0, 0xFEDCBA9876543210LL },
+	{ 0xFEDCBA9876543210LL, 1, 0x7F6E5D4C3B2A1908LL },
+	{ 0xFEDCBA9876543210LL, 2, 0x3FB72EA61D950C84LL },
+	{ 0xFEDCBA9876543210LL, 3, 0x1FDB97530ECA8642LL },
+	{ 0xFEDCBA9876543210LL, 4, 0xFEDCBA987654321LL },
+	{ 0xFEDCBA9876543210LL, 28, 0xFEDCBA987LL },
+	{ 0xFEDCBA9876543210LL, 29, 0x7F6E5D4C3LL },
+	{ 0xFEDCBA9876543210LL, 30, 0x3FB72EA61LL },
+	{ 0xFEDCBA9876543210LL, 31, 0x1FDB97530LL },
+	{ 0xFEDCBA9876543210LL, 32, 0xFEDCBA98LL },
+	{ 0xFEDCBA9876543210LL, 33, 0x7F6E5D4CLL },
+	{ 0xFEDCBA9876543210LL, 34, 0x3FB72EA6LL },
+	{ 0xFEDCBA9876543210LL, 35, 0x1FDB9753LL },
+	{ 0xFEDCBA9876543210LL, 36, 0xFEDCBA9LL },
+	{ 0xAEDCBA9876543210LL, 60, 0xALL },
+	{ 0xAEDCBA9876543210LL, 61, 0x5LL },
+	{ 0xAEDCBA9876543210LL, 62, 0x2LL },
+	{ 0xAEDCBA9876543210LL, 63, 0x1LL },
+};
+
+static void shdi3_test_lshrdi3(struct kunit *test)
+{
+	const struct shdi3_test_entry *e;
+	long long ret;
+
+	for (e = lshrdi3_testdata;
+	     e < lshrdi3_testdata + ARRAY_SIZE(lshrdi3_testdata); e++) {
+		ret = __lshrdi3(e->input, e->shift);
+		KUNIT_EXPECT_EQ_MSG(test, ret, e->result,
+				    "    when evaluating __lshrdi3(%lld, %d)",
+				    e->input, e->shift);
+	}
+}
+
+static struct kunit_case shdi3_test_cases[] = {
+	KUNIT_CASE(shdi3_test_ashldi3),
+	KUNIT_CASE(shdi3_test_ashrdi3),
+	KUNIT_CASE(shdi3_test_lshrdi3),
+	{}
+};
+
+static struct kunit_suite shdi3_test_suite = {
+	.name = "shdi3",
+	.test_cases = shdi3_test_cases,
+};
+kunit_test_suite(shdi3_test_suite);
+
+MODULE_DESCRIPTION("Test cases for __ashldi3(), __ashrdi3(), and __lshrdi3()");
+MODULE_LICENSE("GPL");