diff options
Diffstat (limited to 'core')
| -rw-r--r-- | core/cortex-m/build.mk | 1 | ||||
| -rw-r--r-- | core/cortex-m/fpu.c | 29 | ||||
| -rw-r--r-- | core/cortex-m/init.S | 8 | ||||
| -rw-r--r-- | core/cortex-m/switch.S | 12 | ||||
| -rw-r--r-- | core/cortex-m/task.c | 14 |
5 files changed, 27 insertions, 37 deletions
diff --git a/core/cortex-m/build.mk b/core/cortex-m/build.mk index 7a2f16e4e9..35ad2d0517 100644 --- a/core/cortex-m/build.mk +++ b/core/cortex-m/build.mk @@ -14,5 +14,4 @@ CFLAGS_CPU=-mcpu=cortex-m4 -mthumb -Os -mno-sched-prolog CFLAGS_CPU+=$(CFLAGS_FPU-y) core-y=cpu.o init.o panic.o switch.o task.o timer.o -core-$(CONFIG_FPU)+=fpu.o core-$(CONFIG_TASK_WATCHDOG)+=watchdog.o diff --git a/core/cortex-m/fpu.c b/core/cortex-m/fpu.c deleted file mode 100644 index 806b05438e..0000000000 --- a/core/cortex-m/fpu.c +++ /dev/null @@ -1,29 +0,0 @@ -/* Copyright (c) 2012 The Chromium OS Authors. All rights reserved. - * Use of this source code is governed by a BSD-style license that can be - * found in the LICENSE file. - */ - -/* FPU module for Chrome EC operating system */ - -#include "task.h" - -void enable_fpu(void) -{ - interrupt_disable(); - asm volatile("mrs r0, control;" - "orr r0, r0, #(1 << 2);" - "msr control, r0;" - "isb;"); -} - -void disable_fpu(int32_t v) -{ - /* Optimization barrier to force compiler generate floating point - * calculation code for 'v' before disabling FPU. */ - asm volatile("" : : "r" (v) : "memory"); - asm volatile("mrs r0, control;" - "bic r0, r0, #(1 << 2);" - "msr control, r0;" - "isb;"); - interrupt_enable(); -} diff --git a/core/cortex-m/init.S b/core/cortex-m/init.S index 22cece17cb..30883358f7 100644 --- a/core/cortex-m/init.S +++ b/core/cortex-m/init.S @@ -305,8 +305,12 @@ reset: /* Ensure we're in privileged mode with main stack. * Necessary if we've jumped directly here from another image * after task_start(). */ - mov r0, #0 - msr control, r0 @ use : priv. mode / main stack / no floating point +#ifdef CONFIG_FPU + mov r0, #(1 << 2) @ priv. mode / main stack / floating point on +#else + mov r0, #0 @ priv. mode / main stack / no floating point +#endif + msr control, r0 isb @ ensure the write is done /* Set the vector table on our current code */ ldr r1, =vectors diff --git a/core/cortex-m/switch.S b/core/cortex-m/switch.S index 1f94c15292..92c7e51247 100644 --- a/core/cortex-m/switch.S +++ b/core/cortex-m/switch.S @@ -35,8 +35,8 @@ __switchto: mrs r3, psp @ get the task stack where the context has been saved ldr r2, [r1] @ get the new scheduled task stack pointer - stmdb r3!, {r4-r11} @ save additional r4-r7 in the task stack - ldmia r2!, {r4-r11} @ restore r4-r7 for the next task context + stmdb r3!, {r4-r11} @ save additional r4-r11 in the task stack + ldmia r2!, {r4-r11} @ restore r4-r11 for the next task context str r3, [r0] @ save the task stack pointer in its context msr psp, r2 @ set the process stack pointer to exception context bx lr @ return from exception @@ -49,13 +49,17 @@ __switchto: .thumb_func __task_start: ldr r2,=scratchpad @ area used as dummy thread stack for the first switch - mov r3, #2 +#ifdef CONFIG_FPU + mov r3, #6 @ use : priv. mode / thread stack / floating point on +#else + mov r3, #2 @ use : priv. mode / thread stack / no floating point +#endif add r2, #17*4 @ put the pointer at the top of the stack mov r1, #0 @ __Schedule parameter : re-schedule nothing msr psp, r2 @ setup a thread stack up to the first context switch mov r2, #1 isb @ ensure the write is done - msr control, r3 @ use : priv. mode / thread stack / no floating point + msr control, r3 mov r3, r0 mov r0, #0 @ __Schedule parameter : de-schedule nothing isb @ ensure the write is done diff --git a/core/cortex-m/task.c b/core/cortex-m/task.c index ba6e374501..7b4eb9ddfe 100644 --- a/core/cortex-m/task.c +++ b/core/cortex-m/task.c @@ -120,7 +120,11 @@ uint8_t task_stacks[0 #undef TASK /* Reserve space to discard context on first context switch. */ +#ifdef CONFIG_FPU +uint32_t scratchpad[17+18]; +#else uint32_t scratchpad[17]; +#endif static task_ *current_task = (task_ *)scratchpad; @@ -573,8 +577,16 @@ int task_pre_init(void) tasks[i].stack = stack_next; - /* Update stack used by first frame (16 uint32's) */ + /* + * Update stack used by first frame: 8 words for the normal + * stack, plus 8 for R4-R11. With FP enabled, we need another + * 18 words for S0-S15 and FPCSR and to align to 64-bit. + */ +#ifdef CONFIG_FPU + sp = stack_next + ssize - 16 - 18; +#else sp = stack_next + ssize - 16; +#endif tasks[i].sp = (uint32_t)sp; /* Initial context on stack (see __switchto()) */ |