xref: /openbmc/linux/arch/powerpc/include/asm/elf.h (revision 97e6f135)
1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3  * ELF register definitions..
4  */
5 #ifndef _ASM_POWERPC_ELF_H
6 #define _ASM_POWERPC_ELF_H
7 
8 #include <linux/sched.h>	/* for task_struct */
9 #include <asm/page.h>
10 #include <asm/string.h>
11 #include <uapi/asm/elf.h>
12 
13 /*
14  * This is used to ensure we don't load something for the wrong architecture.
15  * 64le only supports ELFv2 64-bit binaries (64be supports v1 and v2).
16  */
17 #if defined(CONFIG_PPC64) && defined(CONFIG_CPU_LITTLE_ENDIAN)
18 #define elf_check_arch(x) (((x)->e_machine == ELF_ARCH) && \
19 			   (((x)->e_flags & 0x3) == 0x2))
20 #else
21 #define elf_check_arch(x) ((x)->e_machine == ELF_ARCH)
22 #endif
23 #define compat_elf_check_arch(x)	((x)->e_machine == EM_PPC)
24 
25 #define CORE_DUMP_USE_REGSET
26 #define ELF_EXEC_PAGESIZE	PAGE_SIZE
27 
28 /*
29  * This is the base location for PIE (ET_DYN with INTERP) loads. On
30  * 64-bit, this is raised to 4GB to leave the entire 32-bit address
31  * space open for things that want to use the area for 32-bit pointers.
32  */
33 #define ELF_ET_DYN_BASE		(is_32bit_task() ? 0x000400000UL : \
34 						   0x100000000UL)
35 
36 #define ELF_CORE_EFLAGS (is_elf2_task() ? 2 : 0)
37 
38 /*
39  * Our registers are always unsigned longs, whether we're a 32 bit
40  * process or 64 bit, on either a 64 bit or 32 bit kernel.
41  *
42  * This macro relies on elf_regs[i] having the right type to truncate to,
43  * either u32 or u64.  It defines the body of the elf_core_copy_regs
44  * function, either the native one with elf_gregset_t elf_regs or
45  * the 32-bit one with elf_gregset_t32 elf_regs.
46  */
47 #define PPC_ELF_CORE_COPY_REGS(elf_regs, regs) \
48 	int i, nregs = min(sizeof(*regs) / sizeof(unsigned long), \
49 			   (size_t)ELF_NGREG);			  \
50 	for (i = 0; i < nregs; i++) \
51 		elf_regs[i] = ((unsigned long *) regs)[i]; \
52 	memset(&elf_regs[i], 0, (ELF_NGREG - i) * sizeof(elf_regs[0]))
53 
54 /* Common routine for both 32-bit and 64-bit native processes */
55 static inline void ppc_elf_core_copy_regs(elf_gregset_t elf_regs,
56 					  struct pt_regs *regs)
57 {
58 	PPC_ELF_CORE_COPY_REGS(elf_regs, regs);
59 }
60 #define ELF_CORE_COPY_REGS(gregs, regs) ppc_elf_core_copy_regs(gregs, regs);
61 
62 /* ELF_HWCAP yields a mask that user programs can use to figure out what
63    instruction set this cpu supports.  This could be done in userspace,
64    but it's not easy, and we've already done it here.  */
65 # define ELF_HWCAP	(cur_cpu_spec->cpu_user_features)
66 # define ELF_HWCAP2	(cur_cpu_spec->cpu_user_features2)
67 
68 /* This yields a string that ld.so will use to load implementation
69    specific libraries for optimization.  This is more specific in
70    intent than poking at uname or /proc/cpuinfo.  */
71 
72 #define ELF_PLATFORM	(cur_cpu_spec->platform)
73 
74 /* While ELF_PLATFORM indicates the ISA supported by the platform, it
75  * may not accurately reflect the underlying behavior of the hardware
76  * (as in the case of running in Power5+ compatibility mode on a
77  * Power6 machine).  ELF_BASE_PLATFORM allows ld.so to load libraries
78  * that are tuned for the real hardware.
79  */
80 #define ELF_BASE_PLATFORM (powerpc_base_platform)
81 
82 #ifdef __powerpc64__
83 # define ELF_PLAT_INIT(_r, load_addr)	do {	\
84 	_r->gpr[2] = load_addr; 		\
85 } while (0)
86 #endif /* __powerpc64__ */
87 
88 #ifdef __powerpc64__
89 # define SET_PERSONALITY(ex)					\
90 do {								\
91 	if (((ex).e_flags & 0x3) == 2)				\
92 		set_thread_flag(TIF_ELF2ABI);			\
93 	else							\
94 		clear_thread_flag(TIF_ELF2ABI);			\
95 	if ((ex).e_ident[EI_CLASS] == ELFCLASS32)		\
96 		set_thread_flag(TIF_32BIT);			\
97 	else							\
98 		clear_thread_flag(TIF_32BIT);			\
99 	if (personality(current->personality) != PER_LINUX32)	\
100 		set_personality(PER_LINUX |			\
101 			(current->personality & (~PER_MASK)));	\
102 } while (0)
103 /*
104  * An executable for which elf_read_implies_exec() returns TRUE will
105  * have the READ_IMPLIES_EXEC personality flag set automatically. This
106  * is only required to work around bugs in old 32bit toolchains. Since
107  * the 64bit ABI has never had these issues dont enable the workaround
108  * even if we have an executable stack.
109  */
110 # define elf_read_implies_exec(ex, exec_stk) (is_32bit_task() ? \
111 		(exec_stk == EXSTACK_DEFAULT) : 0)
112 #else
113 # define elf_read_implies_exec(ex, exec_stk) (exec_stk == EXSTACK_DEFAULT)
114 #endif /* __powerpc64__ */
115 
116 extern int dcache_bsize;
117 extern int icache_bsize;
118 extern int ucache_bsize;
119 
120 /* vDSO has arch_setup_additional_pages */
121 #define ARCH_HAS_SETUP_ADDITIONAL_PAGES
122 struct linux_binprm;
123 extern int arch_setup_additional_pages(struct linux_binprm *bprm,
124 				       int uses_interp);
125 #define VDSO_AUX_ENT(a,b) NEW_AUX_ENT(a,b)
126 
127 /* 1GB for 64bit, 8MB for 32bit */
128 #define STACK_RND_MASK (is_32bit_task() ? \
129 	(0x7ff >> (PAGE_SHIFT - 12)) : \
130 	(0x3ffff >> (PAGE_SHIFT - 12)))
131 
132 #ifdef CONFIG_SPU_BASE
133 /* Notes used in ET_CORE. Note name is "SPU/<fd>/<filename>". */
134 #define NT_SPU		1
135 
136 #define ARCH_HAVE_EXTRA_ELF_NOTES
137 
138 #endif /* CONFIG_SPU_BASE */
139 
140 #ifdef CONFIG_PPC64
141 
142 #define get_cache_geometry(level) \
143 	(ppc64_caches.level.assoc << 16 | ppc64_caches.level.line_size)
144 
145 #define ARCH_DLINFO_CACHE_GEOMETRY					\
146 	NEW_AUX_ENT(AT_L1I_CACHESIZE, ppc64_caches.l1i.size);		\
147 	NEW_AUX_ENT(AT_L1I_CACHEGEOMETRY, get_cache_geometry(l1i));	\
148 	NEW_AUX_ENT(AT_L1D_CACHESIZE, ppc64_caches.l1d.size);		\
149 	NEW_AUX_ENT(AT_L1D_CACHEGEOMETRY, get_cache_geometry(l1d));	\
150 	NEW_AUX_ENT(AT_L2_CACHESIZE, ppc64_caches.l2.size);		\
151 	NEW_AUX_ENT(AT_L2_CACHEGEOMETRY, get_cache_geometry(l2));	\
152 	NEW_AUX_ENT(AT_L3_CACHESIZE, ppc64_caches.l3.size);		\
153 	NEW_AUX_ENT(AT_L3_CACHEGEOMETRY, get_cache_geometry(l3))
154 
155 #else
156 #define ARCH_DLINFO_CACHE_GEOMETRY
157 #endif
158 
159 /*
160  * The requirements here are:
161  * - keep the final alignment of sp (sp & 0xf)
162  * - make sure the 32-bit value at the first 16 byte aligned position of
163  *   AUXV is greater than 16 for glibc compatibility.
164  *   AT_IGNOREPPC is used for that.
165  * - for compatibility with glibc ARCH_DLINFO must always be defined on PPC,
166  *   even if DLINFO_ARCH_ITEMS goes to zero or is undefined.
167  * update AT_VECTOR_SIZE_ARCH if the number of NEW_AUX_ENT entries changes
168  */
169 #define COMMON_ARCH_DLINFO						\
170 do {									\
171 	/* Handle glibc compatibility. */				\
172 	NEW_AUX_ENT(AT_IGNOREPPC, AT_IGNOREPPC);			\
173 	NEW_AUX_ENT(AT_IGNOREPPC, AT_IGNOREPPC);			\
174 	/* Cache size items */						\
175 	NEW_AUX_ENT(AT_DCACHEBSIZE, dcache_bsize);			\
176 	NEW_AUX_ENT(AT_ICACHEBSIZE, icache_bsize);			\
177 	NEW_AUX_ENT(AT_UCACHEBSIZE, 0);					\
178 	VDSO_AUX_ENT(AT_SYSINFO_EHDR, (unsigned long)current->mm->context.vdso);\
179 	ARCH_DLINFO_CACHE_GEOMETRY;					\
180 } while (0)
181 
182 #define ARCH_DLINFO							\
183 do {									\
184 	COMMON_ARCH_DLINFO;						\
185 	NEW_AUX_ENT(AT_MINSIGSTKSZ, get_min_sigframe_size());		\
186 } while (0)
187 
188 #define COMPAT_ARCH_DLINFO						\
189 do {									\
190 	COMMON_ARCH_DLINFO;						\
191 	NEW_AUX_ENT(AT_MINSIGSTKSZ, get_min_sigframe_size_compat());	\
192 } while (0)
193 
194 /* Relocate the kernel image to @final_address */
195 void relocate(unsigned long final_address);
196 
197 struct func_desc {
198 	unsigned long addr;
199 	unsigned long toc;
200 	unsigned long env;
201 };
202 
203 #endif /* _ASM_POWERPC_ELF_H */
204