voron

experimental ARM OS
git clone git://git.2f30.org/voron.git
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commit b3d543198e48fb97bf0de16a191dcee186a4a5ab
parent ea08b81621fd1ea148c3ef9b63817f0e73e7c65f
Author: oblique <psyberbits@gmail.com>
Date:   Tue Oct 30 12:00:35 +0200

move cpsr variable of struct regs to the end

Diffstat:
include/regs.h | 2+-
kernel/interrupts.S | 35++++++++++++++++++-----------------
2 files changed, 19 insertions(+), 18 deletions(-)
diff --git a/include/regs.h b/include/regs.h @@ -2,7 +2,6 @@ #define __REGS_H struct regs { - u32 cpsr; union { u32 r[16]; struct { @@ -51,6 +50,7 @@ struct regs { u32 pc; /* r15 */ }; }; + u32 cpsr; }; #endif /* __REGS_H */ diff --git a/kernel/interrupts.S b/kernel/interrupts.S @@ -28,11 +28,12 @@ vector_table: @@ save all the registers .macro SAVE_ALL_EX + sub sp, sp, #4 @ make space for cpsr variable (cpsr of the previous mode) stmfd sp!, { lr } @ save lr (pc (r15) of the previous mode) sub sp, sp, #8 @ make space for sp (r13) and lr (r14) registers stmfd sp!, { r0 - r12 } @ save r0 until r12 - mrs r0, spsr @ save spsr (cpsr of the previus mode) - str r0, [sp, #-4]! @ save cpsr + mrs r0, spsr @ read spsr (cpsr of the previous mode) + str r0, [sp, #(4 * 16)] @ save cpsr variable bic r0, r0, #0x60 @ clear F, T flags orr r0, r0, #(1 << 7) @ set I flag mrs r2, cpsr @ backup current cpsr @@ -40,31 +41,31 @@ vector_table: mov r0, sp mov r1, lr msr cpsr, r2 @ swith back to the current mode - str r0, [sp, #(4 * 14)] @ save sp (r13) - str r1, [sp, #(4 * 15)] @ save lr (r14) - - ldr r0, [sp, #4] @ restore destroyed registers + str r0, [sp, #(4 * 13)] @ save sp (r13) + str r1, [sp, #(4 * 14)] @ save lr (r14) + @@ restore destroyed registers + ldr r0, [sp, #4] ldr r1, [sp, #8] ldr r2, [sp, #12] .endm @@ restore registers .macro RESTORE_ALL_EX - ldr r1, [sp, #(4 * 14)] @ load sp (r13) - ldr r2, [sp, #(4 * 15)] @ load lr (r14) - ldr r0, [sp] - bic r0, r0, #0x60 - orr r0, r0, #(1 << 7) @ get the previous mode number - mrs r3, cpsr - msr cpsr_c, r0 @ switch to previous mode - mov sp, r1 - mov lr, r2 + ldr r0, [sp, #(4 * 13)] @ load sp (r13) + ldr r1, [sp, #(4 * 14)] @ load lr (r14) + ldr r2, [sp, #(4 * 16)] @ load cpsr variable + msr spsr, r2 @ restore spsr + bic r2, r2, #0x60 @ clear F, T flags + orr r2, r2, #(1 << 7) @ set I flag + mrs r3, cpsr @ backup current cpsr + msr cpsr_c, r2 @ switch to previous mode + mov sp, r0 + mov lr, r1 msr cpsr, r3 @ swith back to the current mode - ldr r0, [sp], #4 @ load spsr (cpsr of the previus mode) - msr spsr, r0 ldmfd sp!, { r0 - r12 } add sp, sp, #8 @ release the space we had for sp (r13) and lr (r14) ldr lr, [sp], #4 @ load lr (pc (r15) of the previous mode) + add sp, sp, #4 @ release the space we had for cpsr variable .endm