pinebuds/platform/cmsis/mpu_armv7m.c
2022-08-15 17:20:27 +08:00

369 lines
8.7 KiB
C

/***************************************************************************
*
* Copyright 2015-2019 BES.
* All rights reserved. All unpublished rights reserved.
*
* No part of this work may be used or reproduced in any form or by any
* means, or stored in a database or retrieval system, without prior written
* permission of BES.
*
* Use of this work is governed by a license granted by BES.
* This work contains confidential and proprietary information of
* BES. which is protected by copyright, trade secret,
* trademark and other intellectual property rights.
*
****************************************************************************/
#ifndef __ARM_ARCH_ISA_ARM
#include "mpu.h"
#include "cmsis.h"
#include "hal_trace.h"
int mpu_open(void)
{
int i;
if ((MPU->TYPE & MPU_TYPE_DREGION_Msk) == 0) {
return 1;
}
ARM_MPU_Disable();
for (i = 0; i < MPU_ID_QTY; i++) {
ARM_MPU_ClrRegion(i);
}
ARM_MPU_Enable(MPU_CTRL_PRIVDEFENA_Msk);
return 0;
}
int mpu_close(void)
{
ARM_MPU_Disable();
return 0;
}
static int mpu_set_armv7(enum MPU_ID_T id, uint32_t addr, uint32_t len,
int srd_bits, enum MPU_ATTR_T attr)
{
int ret;
uint32_t rbar;
uint32_t rasr;
uint8_t xn;
uint8_t ap;
uint8_t size;
if ((MPU->CTRL & MPU_CTRL_ENABLE_Msk) == 0) {
ret = mpu_open();
if (ret) {
return ret;
}
}
if (id >= MPU_ID_QTY) {
return 2;
}
if (len < 32 || (len & (len - 1))) {
return 3;
}
if (addr & (len - 1)) {
return 4;
}
if (attr >= MPU_ATTR_QTY) {
return 5;
}
if (attr == MPU_ATTR_READ_WRITE_EXEC || attr == MPU_ATTR_READ_EXEC ||
attr == MPU_ATTR_EXEC) {
xn = 0;
} else {
xn = 1;
}
ap = ARM_MPU_AP_NONE;
if (attr == MPU_ATTR_READ_WRITE_EXEC || attr == MPU_ATTR_READ_WRITE) {
ap = ARM_MPU_AP_FULL;
} else if (attr == MPU_ATTR_READ_EXEC || attr == MPU_ATTR_READ) {
ap = ARM_MPU_AP_RO;
}
size = __CLZ(__RBIT(len)) - 1;
ARM_MPU_Disable();
rbar = ARM_MPU_RBAR(id, addr);
// Type Extention: 0
// Shareable: 1
// Cacheable: 1
// Bufferable: 1
// Subregion: 0
rasr = ARM_MPU_RASR(xn, ap, 0, 1, 1, 1, srd_bits, size);
ARM_MPU_SetRegion(rbar, rasr);
ARM_MPU_Enable(MPU_CTRL_PRIVDEFENA_Msk);
__DSB();
__ISB();
return 0;
}
/*
* sub region is 8 bits, and if one bits is 1, the sub resion will be
* disabled
* like 0b00011111, the top 3 sub region will be disabled
* if it is 0b11110000, the bottom 4 sub region will be disabled.
*/
static int mpu_get_top_srd(uint32_t rg_end, uint32_t fr_end,
uint32_t sub_rg_sz)
{
int dis_nums;
uint8_t srd_bits;
dis_nums = (rg_end - fr_end) / sub_rg_sz;
if ((fr_end & (sub_rg_sz - 1)) != 0)
dis_nums += 1;
srd_bits = 0xff;
srd_bits &= ~((1UL << (8 - dis_nums)) - 1);
return srd_bits;
}
static int mpu_get_bottom_srd(uint32_t rg_start, uint32_t fr_start,
uint32_t sub_rg_sz)
{
int dis_nums;
uint8_t srd_bits;
dis_nums = (fr_start - rg_start) / sub_rg_sz;
srd_bits = 0xff;
srd_bits &= ((1UL << dis_nums) - 1);
return srd_bits;
}
static int calc_sub_region_size(uint32_t fr_start)
{
int lsb_bit;
uint32_t sz;
//sub region size aligned to fram start
lsb_bit = get_lsb_pos(fr_start);
sz = 1 << lsb_bit;
if (sz < 0x80) {
/*cortex-m4 doesn't support sub region size less than 128 */
TRACE(1,"no mpu region for fram start %x", fr_start);
return -1;
}
if (sz > 0x4000)
sz = 0x4000;
return sz;
}
/*
Allocate two mpu sections to protect the fast ram. The cortext M4
mpu has a lot of restrict, such as one region's start address must
be aligned to the size of region, and the sub region number is fixed
to 8.
The layout like:
------------------
| sub region 8 |
------------------
| sub region 7 |
| ..... |
| |
------------------>fast_ram_end
|////////////////|
|////////////////|
|////////////////|
|////////////////|
------------------>mpu region2
|//sub region 8//|
|////////////////|
|////////////////|
|////////////////|
------------------>fast_ram_start aligned to sub region size
| ..... |
| |
|sub region 1 |
------------------
|sub region 0 |
------------------>mpu region1
If the __fast_sram_text_exec_end__ exceed the region2's end, just leave
the rest unprotect.
*/
static int mpu_fram_protect_armv7(uint32_t fr_start, uint32_t fr_end)
{
uint32_t fr_sz;
uint32_t sub_rg_sz;
uint32_t rg_sz;
uint32_t rg_start;
uint32_t rg_end;
int ret = 0;
int srd_bits;
int finished = 0;
fr_sz = fr_end - fr_start;
sub_rg_sz = calc_sub_region_size(fr_start);
if (sub_rg_sz < 0)
return -1;
/* according to cortex-m4 spec, the region is divived to 8 sub region*/
rg_sz = sub_rg_sz * 8;
/*now we just protect two region */
if (fr_sz > (rg_sz * 2)) {
TRACE(0,"Warning fram is too big, mpu can not protect so much");
TRACE(2,"region_sz %x, fram size %x", rg_sz, fr_sz);
}
/*aliged the region start to region size according to cortext m4 spec*/
srd_bits = 0;
rg_start = fr_start & ~(rg_sz - 1);
if (fr_start > rg_start) {
int b_srd_bits = 0;
b_srd_bits = mpu_get_bottom_srd(rg_start, fr_start, sub_rg_sz);
srd_bits |= b_srd_bits;
}
rg_end = rg_start + rg_sz;
if (fr_end < rg_end) {
int t_srd_bits = 0;
t_srd_bits = mpu_get_top_srd(rg_end, fr_end, sub_rg_sz);
srd_bits |= t_srd_bits;
finished = 1;
}
ret = mpu_set(MPU_ID_FRAM_TEXT1, rg_start, rg_sz, srd_bits, MPU_ATTR_READ);
if (ret || finished)
goto out;
/* need another section, and start from next region*/
rg_start += rg_sz;
srd_bits = 0;
rg_end = rg_start + rg_sz;
if (fr_end < rg_end) {
srd_bits = mpu_get_top_srd(rg_end, fr_end, sub_rg_sz);
}
ret = mpu_set(MPU_ID_FRAM_TEXT2, rg_start, rg_sz, srd_bits, MPU_ATTR_READ_EXEC);
/* if fr_end large than two section, just pass */
out:
return ret;
}
int mpu_set(enum MPU_ID_T id, uint32_t addr, uint32_t len, int srd_bits,
enum MPU_ATTR_T attr)
{
return mpu_set_armv7(id, addr, len, srd_bits, attr);
}
int mpu_clear(enum MPU_ID_T id)
{
uint32_t lock;
if (id >= MPU_ID_QTY) {
return 2;
}
lock = int_lock();
ARM_MPU_ClrRegion(id);
__DSB();
__ISB();
int_unlock(lock);
return 0;
}
static int mpu_null_check_enable(void)
{
#ifdef CHIP_BEST1000
uint32_t len = 0x400;
#else
uint32_t len = 0x800;
#endif
return mpu_set(MPU_ID_NULL_POINTER, 0, len, 0, MPU_ATTR_NO_ACCESS);
}
extern uint32_t __fast_sram_text_exec_start__[];
extern uint32_t __fast_sram_text_exec_end__[];
static int mpu_fast_ram_protect(void)
{
uint32_t ramx_start = (uint32_t)__fast_sram_text_exec_start__;
uint32_t ramx_end = (uint32_t)__fast_sram_text_exec_end__;
uint32_t ram_start = RAMX_TO_RAM(ramx_start);
uint32_t ram_end = RAMX_TO_RAM(ramx_end);
return mpu_fram_protect_armv7(ram_start, ram_end);
}
#if 0
int mpu_fram_test(void)
{
uint32_t ramx_start = (uint32_t)__fast_sram_text_exec_start__;
uint32_t ram_start = RAMX_TO_RAM(ramx_start);
uint32_t test_start = ram_start - 1024;
for (int i = 0; i < 1024; i++) {
TRACE(1,"test_start %x", test_start);
*(volatile uint32_t *)test_start = 0x1;
test_start += 128;
}
uint32_t ramx_end = (uint32_t)__fast_sram_text_exec_end__;
uint32_t ram_end = RAMX_TO_RAM(ramx_end);
uint32_t test_end = ram_end + 1024;
for (int i = 0; i < 1024; i++) {
TRACE(1,"test_end %x", test_end);
*(volatile uint32_t *)test_end = 0x1;
test_end -= 128;
}
return 0;
}
#endif
int mpu_setup(void)
{
mpu_null_check_enable();
mpu_fast_ram_protect();
return 0;
}
int mpu_setup_cp(const mpu_regions_t *mpu_table, uint32_t region_num)
{
int ret;
int i;
ret = mpu_open();
if (ret) {
return ret;
}
if (region_num > MPU_ID_QTY) {
return -1;
}
for (i = 0; i < region_num; i++) {
const mpu_regions_t *region;
region = &mpu_table[i];
ret = mpu_set(i, region->addr, region->len, 0, region->ap_attr);
if (ret)
break;
}
return ret;
}
#endif