RISC-V: Fix the rv32i kernel build

These patches for building 32-bit RISC-V kernel.
 - Fix the compile errors and warnings on RV32I.
 - Fix some incompatible problem on RV32I.
 - Add format.h for compatible of print format.

The fixed width integer types format for Elf_Addr will move to
generic header by another patch. For now, there are some warning
about unexpected argument of type on RV32I.

Change in v1:
 - Fix some error in v1
 - Remove implementation of fixed width integer types format for Elf_Addr.

Author: palmer-dabbelt

arch/riscv/Kconfig

@@ -107,6 +107,7 @@ config ARCH_RV32I
 	select GENERIC_LIB_ASHLDI3
 	select GENERIC_LIB_ASHRDI3
 	select GENERIC_LIB_LSHRDI3
+	select GENERIC_LIB_UCMPDI2
 
 config ARCH_RV64I
 	bool "RV64I"

arch/riscv/include/uapi/asm/elf.h

@@ -21,8 +21,13 @@ typedef struct user_regs_struct elf_gregset_t;
 
 typedef union __riscv_fp_state elf_fpregset_t;
 
-#define ELF_RISCV_R_SYM(r_info) ((r_info) >> 32)
-#define ELF_RISCV_R_TYPE(r_info) ((r_info) & 0xffffffff)
+#if __riscv_xlen == 64
+#define ELF_RISCV_R_SYM(r_info)		ELF64_R_SYM(r_info)
+#define ELF_RISCV_R_TYPE(r_info)	ELF64_R_TYPE(r_info)
+#else
+#define ELF_RISCV_R_SYM(r_info)		ELF32_R_SYM(r_info)
+#define ELF_RISCV_R_TYPE(r_info)	ELF32_R_TYPE(r_info)
+#endif
 
 /*
  * RISC-V relocation types

arch/riscv/kernel/module.c

@@ -37,7 +37,7 @@ static int apply_r_riscv_64_rela(struct module *me, u32 *location, Elf_Addr v)
 static int apply_r_riscv_branch_rela(struct module *me, u32 *location,
 				     Elf_Addr v)
 {
-	s64 offset = (void *)v - (void *)location;
+	ptrdiff_t offset = (void *)v - (void *)location;
 	u32 imm12 = (offset & 0x1000) << (31 - 12);
 	u32 imm11 = (offset & 0x800) >> (11 - 7);
 	u32 imm10_5 = (offset & 0x7e0) << (30 - 10);
@@ -50,7 +50,7 @@ static int apply_r_riscv_branch_rela(struct module *me, u32 *location,
 static int apply_r_riscv_jal_rela(struct module *me, u32 *location,
 				  Elf_Addr v)
 {
-	s64 offset = (void *)v - (void *)location;
+	ptrdiff_t offset = (void *)v - (void *)location;
 	u32 imm20 = (offset & 0x100000) << (31 - 20);
 	u32 imm19_12 = (offset & 0xff000);
 	u32 imm11 = (offset & 0x800) << (20 - 11);
@@ -63,7 +63,7 @@ static int apply_r_riscv_jal_rela(struct module *me, u32 *location,
 static int apply_r_riscv_rcv_branch_rela(struct module *me, u32 *location,
 					 Elf_Addr v)
 {
-	s64 offset = (void *)v - (void *)location;
+	ptrdiff_t offset = (void *)v - (void *)location;
 	u16 imm8 = (offset & 0x100) << (12 - 8);
 	u16 imm7_6 = (offset & 0xc0) >> (6 - 5);
 	u16 imm5 = (offset & 0x20) >> (5 - 2);
@@ -78,7 +78,7 @@ static int apply_r_riscv_rcv_branch_rela(struct module *me, u32 *location,
 static int apply_r_riscv_rvc_jump_rela(struct module *me, u32 *location,
 				       Elf_Addr v)
 {
-	s64 offset = (void *)v - (void *)location;
+	ptrdiff_t offset = (void *)v - (void *)location;
 	u16 imm11 = (offset & 0x800) << (12 - 11);
 	u16 imm10 = (offset & 0x400) >> (10 - 8);
 	u16 imm9_8 = (offset & 0x300) << (12 - 11);
@@ -96,7 +96,7 @@ static int apply_r_riscv_rvc_jump_rela(struct module *me, u32 *location,
 static int apply_r_riscv_pcrel_hi20_rela(struct module *me, u32 *location,
 					 Elf_Addr v)
 {
-	s64 offset = (void *)v - (void *)location;
+	ptrdiff_t offset = (void *)v - (void *)location;
 	s32 hi20;
 
 	if (offset != (s32)offset) {
@@ -178,7 +178,7 @@ static int apply_r_riscv_lo12_s_rela(struct module *me, u32 *location,
 static int apply_r_riscv_got_hi20_rela(struct module *me, u32 *location,
 				       Elf_Addr v)
 {
-	s64 offset = (void *)v - (void *)location;
+	ptrdiff_t offset = (void *)v - (void *)location;
 	s32 hi20;
 
 	/* Always emit the got entry */
@@ -200,7 +200,7 @@ static int apply_r_riscv_got_hi20_rela(struct module *me, u32 *location,
 static int apply_r_riscv_call_plt_rela(struct module *me, u32 *location,
 				       Elf_Addr v)
 {
-	s64 offset = (void *)v - (void *)location;
+	ptrdiff_t offset = (void *)v - (void *)location;
 	s32 fill_v = offset;
 	u32 hi20, lo12;
 
@@ -227,7 +227,7 @@ static int apply_r_riscv_call_plt_rela(struct module *me, u32 *location,
 static int apply_r_riscv_call_rela(struct module *me, u32 *location,
 				   Elf_Addr v)
 {
-	s64 offset = (void *)v - (void *)location;
+	ptrdiff_t offset = (void *)v - (void *)location;
 	s32 fill_v = offset;
 	u32 hi20, lo12;
 
@@ -347,7 +347,7 @@ int apply_relocate_add(Elf_Shdr *sechdrs, const char *strtab,
 			unsigned int j;
 
 			for (j = 0; j < sechdrs[relsec].sh_size / sizeof(*rel); j++) {
-				u64 hi20_loc =
+				unsigned long hi20_loc =
 					sechdrs[sechdrs[relsec].sh_info].sh_addr
 					+ rel[j].r_offset;
 				u32 hi20_type = ELF_RISCV_R_TYPE(rel[j].r_info);
@@ -360,12 +360,12 @@ int apply_relocate_add(Elf_Shdr *sechdrs, const char *strtab,
 					Elf_Sym *hi20_sym =
 						(Elf_Sym *)sechdrs[symindex].sh_addr
 						+ ELF_RISCV_R_SYM(rel[j].r_info);
-					u64 hi20_sym_val =
+					unsigned long hi20_sym_val =
 						hi20_sym->st_value
 						+ rel[j].r_addend;
 
 					/* Calculate lo12 */
-					u64 offset = hi20_sym_val - hi20_loc;
+					size_t offset = hi20_sym_val - hi20_loc;
 					if (IS_ENABLED(CONFIG_MODULE_SECTIONS)
 					    && hi20_type == R_RISCV_GOT_HI20) {
 						offset = module_emit_got_entry(

arch/riscv/mm/init.c

@@ -28,7 +28,9 @@ static void __init zone_sizes_init(void)
 {
 	unsigned long max_zone_pfns[MAX_NR_ZONES] = { 0, };
 
+#ifdef CONFIG_ZONE_DMA32
 	max_zone_pfns[ZONE_DMA32] = PFN_DOWN(min(4UL * SZ_1G, max_low_pfn));
+#endif
 	max_zone_pfns[ZONE_NORMAL] = max_low_pfn;
 
 	free_area_init_nodes(max_zone_pfns);