| 35,7 → 35,6 |
|---|
| |
| #include <userspace.h> |
| |
| |
| /** Struct for holding all general purpose registers. |
| * |
| * Used to set registers when going to userspace. |
| 59,50 → 58,48 |
|---|
| uint32_t pc; |
| } ustate_t; |
| |
| |
| /** Changes processor mode and jumps to the address specified in the first parameter. |
| /** Changes processor mode and jumps to the address specified in the first |
| * parameter. |
| * |
| * @param kernel_uarg Userspace settings (entry point, stack, ...). |
| */ |
| void userspace(uspace_arg_t *kernel_uarg) |
| { |
| |
| volatile ustate_t ustate; |
| |
| // set first parameter |
| /* set first parameter */ |
| ustate.r0 = (uintptr_t) kernel_uarg->uspace_uarg; |
| |
| // clear other registers |
| ustate.r1 = ustate.r2 = ustate.r3 = ustate.r4 = |
| ustate.r5 = ustate.r6 = ustate.r7 = ustate.r8 = |
| ustate.r9 = ustate.r10 = ustate.r11 = ustate.r12 = |
| ustate.lr = 0; |
| /* clear other registers */ |
| ustate.r1 = ustate.r2 = ustate.r3 = ustate.r4 = ustate.r5 = |
| ustate.r6 = ustate.r7 = ustate.r8 = ustate.r9 = ustate.r10 = |
| ustate.r11 = ustate.r12 = ustate.lr = 0; |
| |
| // set user stack |
| /* set user stack */ |
| ustate.sp = ((uint32_t)kernel_uarg->uspace_stack) + PAGE_SIZE; |
| |
| // set where uspace execution starts |
| /* set where uspace execution starts */ |
| ustate.pc = (uintptr_t) kernel_uarg->uspace_entry; |
| |
| // status register in user mode |
| ipl_t user_mode = current_status_reg_read() & (~STATUS_REG_MODE_MASK | USER_MODE); |
| /* status register in user mode */ |
| ipl_t user_mode = current_status_reg_read() & |
| (~STATUS_REG_MODE_MASK | USER_MODE); |
| |
| // set user mode, set registers, jump |
| asm __volatile__ ( |
| "mov r0, %0 \n" |
| "msr spsr_c, %1 \n" |
| "ldmfd r0!, {r0-r12, sp, lr}^ \n" |
| "ldmfd r0!, {pc}^" |
| |
| /* set user mode, set registers, jump */ |
| asm volatile ( |
| "mov r0, %0 \n" |
| "msr spsr_c, %1 \n" |
| "ldmfd r0!, {r0-r12, sp, lr}^ \n" |
| "ldmfd r0!, {pc}^\n" |
| : |
| : "r"(&ustate), "r"(user_mode) |
| : "r" (&ustate), "r" (user_mode) |
| : "r0", "r1" |
| ); |
| |
| // unreachable |
| while(1) ; |
| /* unreachable */ |
| while(1) |
| ; |
| } |
| |
| |
| /** @} |
| */ |