u-boot-brain/examples/standalone/stubs.c
Andy Shevchenko daab59ac05 avr32: Retire AVR32 for good
AVR32 is gone. It's already more than two years for no support in Buildroot,
even longer there is no support in GCC (last version is heavily patched 4.2.4).

Linux kernel v4.12 got rid of it (and v4.11 didn't build successfully).

There is no good point to keep this support in U-Boot either.

Reviewed-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Tom Rini <trini@konsulko.com>
Reviewed-by: Heiko Schocher <hs@denx.de>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
2017-07-06 16:17:19 -04:00

275 lines
6.8 KiB
C

#include <common.h>
#include <exports.h>
#include <linux/compiler.h>
#define FO(x) offsetof(struct jt_funcs, x)
#if defined(CONFIG_X86)
/*
* x86 does not have a dedicated register to store the pointer to
* the global_data. Thus the jump table address is stored in a
* global variable, but such approach does not allow for execution
* from flash memory. The global_data address is passed as argv[-1]
* to the application program.
*/
static struct jt_funcs *jt;
gd_t *global_data;
#define EXPORT_FUNC(f, a, x, ...) \
asm volatile ( \
" .globl " #x "\n" \
#x ":\n" \
" movl %0, %%eax\n" \
" movl jt, %%ecx\n" \
" jmp *(%%ecx, %%eax)\n" \
: : "i"(FO(x)) : "eax", "ecx");
#elif defined(CONFIG_PPC)
/*
* r2 holds the pointer to the global_data, r11 is a call-clobbered
* register
*/
#define EXPORT_FUNC(f, a, x, ...) \
asm volatile ( \
" .globl " #x "\n" \
#x ":\n" \
" lwz %%r11, %0(%%r2)\n" \
" lwz %%r11, %1(%%r11)\n" \
" mtctr %%r11\n" \
" bctr\n" \
: : "i"(offsetof(gd_t, jt)), "i"(FO(x)) : "r11");
#elif defined(CONFIG_ARM)
#ifdef CONFIG_ARM64
/*
* x18 holds the pointer to the global_data, x9 is a call-clobbered
* register
*/
#define EXPORT_FUNC(f, a, x, ...) \
asm volatile ( \
" .globl " #x "\n" \
#x ":\n" \
" ldr x9, [x18, %0]\n" \
" ldr x9, [x9, %1]\n" \
" br x9\n" \
: : "i"(offsetof(gd_t, jt)), "i"(FO(x)) : "x9");
#else
/*
* r9 holds the pointer to the global_data, ip is a call-clobbered
* register
*/
#define EXPORT_FUNC(f, a, x, ...) \
asm volatile ( \
" .globl " #x "\n" \
#x ":\n" \
" ldr ip, [r9, %0]\n" \
" ldr pc, [ip, %1]\n" \
: : "i"(offsetof(gd_t, jt)), "i"(FO(x)) : "ip");
#endif
#elif defined(CONFIG_MIPS)
#ifdef CONFIG_CPU_MIPS64
/*
* k0 ($26) holds the pointer to the global_data; t9 ($25) is a call-
* clobbered register that is also used to set gp ($26). Note that the
* jr instruction also executes the instruction immediately following
* it; however, GCC/mips generates an additional `nop' after each asm
* statement
*/
#define EXPORT_FUNC(f, a, x, ...) \
asm volatile ( \
" .globl " #x "\n" \
#x ":\n" \
" ld $25, %0($26)\n" \
" ld $25, %1($25)\n" \
" jr $25\n" \
: : "i"(offsetof(gd_t, jt)), "i"(FO(x)) : "t9");
#else
/*
* k0 ($26) holds the pointer to the global_data; t9 ($25) is a call-
* clobbered register that is also used to set gp ($26). Note that the
* jr instruction also executes the instruction immediately following
* it; however, GCC/mips generates an additional `nop' after each asm
* statement
*/
#define EXPORT_FUNC(f, a, x, ...) \
asm volatile ( \
" .globl " #x "\n" \
#x ":\n" \
" lw $25, %0($26)\n" \
" lw $25, %1($25)\n" \
" jr $25\n" \
: : "i"(offsetof(gd_t, jt)), "i"(FO(x)) : "t9");
#endif
#elif defined(CONFIG_NIOS2)
/*
* gp holds the pointer to the global_data, r8 is call-clobbered
*/
#define EXPORT_FUNC(f, a, x, ...) \
asm volatile ( \
" .globl " #x "\n" \
#x ":\n" \
" movhi r8, %%hi(%0)\n" \
" ori r8, r0, %%lo(%0)\n" \
" add r8, r8, gp\n" \
" ldw r8, 0(r8)\n" \
" ldw r8, %1(r8)\n" \
" jmp r8\n" \
: : "i"(offsetof(gd_t, jt)), "i"(FO(x)) : "gp");
#elif defined(CONFIG_M68K)
/*
* d7 holds the pointer to the global_data, a0 is a call-clobbered
* register
*/
#define EXPORT_FUNC(f, a, x, ...) \
asm volatile ( \
" .globl " #x "\n" \
#x ":\n" \
" move.l %%d7, %%a0\n" \
" adda.l %0, %%a0\n" \
" move.l (%%a0), %%a0\n" \
" adda.l %1, %%a0\n" \
" move.l (%%a0), %%a0\n" \
" jmp (%%a0)\n" \
: : "i"(offsetof(gd_t, jt)), "i"(FO(x)) : "a0");
#elif defined(CONFIG_MICROBLAZE)
/*
* r31 holds the pointer to the global_data. r5 is a call-clobbered.
*/
#define EXPORT_FUNC(f, a, x, ...) \
asm volatile ( \
" .globl " #x "\n" \
#x ":\n" \
" lwi r5, r31, %0\n" \
" lwi r5, r5, %1\n" \
" bra r5\n" \
: : "i"(offsetof(gd_t, jt)), "i"(FO(x)) : "r5");
#elif defined(CONFIG_SH)
/*
* r13 holds the pointer to the global_data. r1 is a call clobbered.
*/
#define EXPORT_FUNC(f, a, x, ...) \
asm volatile ( \
" .align 2\n" \
" .globl " #x "\n" \
#x ":\n" \
" mov r13, r1\n" \
" add %0, r1\n" \
" mov.l @r1, r2\n" \
" add %1, r2\n" \
" mov.l @r2, r1\n" \
" jmp @r1\n" \
" nop\n" \
" nop\n" \
: : "i"(offsetof(gd_t, jt)), "i"(FO(x)) : "r1", "r2");
#elif defined(CONFIG_NDS32)
/*
* r16 holds the pointer to the global_data. gp is call clobbered.
* not support reduced register (16 GPR).
*/
#define EXPORT_FUNC(f, a, x, ...) \
asm volatile ( \
" .globl " #x "\n" \
#x ":\n" \
" lwi $r16, [$gp + (%0)]\n" \
" lwi $r16, [$r16 + (%1)]\n" \
" jr $r16\n" \
: : "i"(offsetof(gd_t, jt)), "i"(FO(x)) : "$r16");
#elif defined(CONFIG_ARC)
/*
* r25 holds the pointer to the global_data. r10 is call clobbered.
*/
#define EXPORT_FUNC(f, a, x, ...) \
asm volatile( \
" .align 4\n" \
" .globl " #x "\n" \
#x ":\n" \
" ld r10, [r25, %0]\n" \
" ld r10, [r10, %1]\n" \
" j [r10]\n" \
: : "i"(offsetof(gd_t, jt)), "i"(FO(x)) : "r10");
#elif defined(CONFIG_XTENSA)
/*
* Global data ptr is in global_data, jump table ptr is in jt.
* Windowed ABI: Jump just past 'entry' in target and adjust stack frame
* (extract stack frame size from target 'entry' instruction).
*/
static void **jt;
#if defined(__XTENSA_CALL0_ABI__)
#define EXPORT_FUNC(f, a, x, ...) \
asm volatile ( \
" .extern jt\n" \
" .globl " #x "\n" \
" .align 4\n" \
#x ":\n" \
" l32i a8, %0, 0\n" \
" l32i a8, a8, %1\n" \
" jx a8\n" \
: : "r"(jt), "i" (FO(x)) : "a8");
#elif defined(__XTENSA_WINDOWED_ABI__)
#if XCHAL_HAVE_BE
# define SFT "8"
#else
# define SFT "12"
#endif
#define EXPORT_FUNC(f, a, x, ...) \
asm volatile ( \
" .extern jt\n" \
" .globl " #x "\n" \
" .align 4\n" \
#x ":\n" \
" entry sp, 16\n" \
" l32i a8, %0, 0\n" \
" l32i a8, a8, %1\n" \
" l32i a9, a8, 0\n" \
" extui a9, a9, " SFT ", 12\n" \
" subx8 a9, a9, sp\n" \
" movi a10, 16\n" \
" sub a9, a10, a9\n" \
" movsp sp, a9\n" \
" addi a8, a8, 3\n" \
" jx a8\n" \
: : "r"(jt), "i" (FO(x)) : "a8", "a9", "a10");
#else
#error Unsupported Xtensa ABI
#endif
#else
/*" addi $sp, $sp, -24\n" \
" br $r16\n" \*/
#error stubs definition missing for this architecture
#endif
/* This function is necessary to prevent the compiler from
* generating prologue/epilogue, preparing stack frame etc.
* The stub functions are special, they do not use the stack
* frame passed to them, but pass it intact to the actual
* implementation. On the other hand, asm() statements with
* arguments can be used only inside the functions (gcc limitation)
*/
#if GCC_VERSION < 30400
static
#endif /* GCC_VERSION */
void __attribute__((unused)) dummy(void)
{
#include <_exports.h>
}
#include <asm/sections.h>
void app_startup(char * const *argv)
{
char *cp = __bss_start;
/* Zero out BSS */
while (cp < _end)
*cp++ = 0;
#if defined(CONFIG_X86)
/* x86 does not have a dedicated register for passing global_data */
global_data = (gd_t *)argv[-1];
jt = global_data->jt;
#endif
}
#undef EXPORT_FUNC