xiaoxiang781216 commented on code in PR #12807: URL: https://github.com/apache/nuttx/pull/12807#discussion_r1697098050
########## arch/risc-v/src/qemu-rv/qemu_rv_userspace.c: ########## @@ -0,0 +1,137 @@ +/**************************************************************************** + * arch/risc-v/src/qemu-rv/qemu_rv_userspace.c + * + * Licensed to the Apache Software Foundation (ASF) under one or more + * contributor license agreements. See the NOTICE file distributed with + * this work for additional information regarding copyright ownership. The + * ASF licenses this file to you under the Apache License, Version 2.0 (the + * "License"); you may not use this file except in compliance with the + * License. You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT + * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the + * License for the specific language governing permissions and limitations + * under the License. + * + ****************************************************************************/ + +/**************************************************************************** + * Included Files + ****************************************************************************/ + +#include <nuttx/config.h> + +#include <stdint.h> +#include <assert.h> + +#include <nuttx/queue.h> +#include <nuttx/userspace.h> + +#include <arch/board/board_memorymap.h> + +#include "qemu_rv_userspace.h" +#include "riscv_internal.h" + +#ifdef CONFIG_BUILD_PROTECTED + +/**************************************************************************** + * Pre-processor Definitions + ****************************************************************************/ + +#define UFLASH_F (PMPCFG_A_NAPOT | PMPCFG_X | PMPCFG_R) +#define USRAM_F (PMPCFG_A_NAPOT | PMPCFG_W | PMPCFG_R) + +/**************************************************************************** + * Private Types + ****************************************************************************/ + +/**************************************************************************** + * Private Function Prototypes + ****************************************************************************/ + +/**************************************************************************** + * Name: configure_mpu + * + * Description: + * This function configures the MPU for for kernel- / userspace separation. + * It will also grant access to the page table memory for the supervisor. + * + ****************************************************************************/ + +static void configure_mpu(void); + +/**************************************************************************** + * Public Functions + ****************************************************************************/ + +/**************************************************************************** + * Name: qemu_rv_userspace + * + * Description: + * For the case of the separate user-/kernel-space build, perform whatever + * platform specific initialization of the user memory is required. + * Normally this just means initializing the user space .data and .bss + * segments. + * + ****************************************************************************/ + +void qemu_rv_userspace(void) +{ + uint8_t *src; + uint8_t *dest; + uint8_t *end; + + /* Clear all of user-space .bss */ + + DEBUGASSERT(USERSPACE->us_bssstart != 0 && USERSPACE->us_bssend != 0 && + USERSPACE->us_bssstart <= USERSPACE->us_bssend); + + dest = (uint8_t *)USERSPACE->us_bssstart; + end = (uint8_t *)USERSPACE->us_bssend; + + while (dest != end) + { + *dest++ = 0; + } + + /* Initialize all of user-space .data */ + + DEBUGASSERT(USERSPACE->us_datasource != 0 && + USERSPACE->us_datastart != 0 && USERSPACE->us_dataend != 0 && + USERSPACE->us_datastart <= USERSPACE->us_dataend); + + src = (uint8_t *)USERSPACE->us_datasource; + dest = (uint8_t *)USERSPACE->us_datastart; + end = (uint8_t *)USERSPACE->us_dataend; + + while (dest != end) + { + *dest++ = *src++; + } + + /* Configure MPU / PMP to grant access to the userspace */ + + configure_mpu(); +} + +/**************************************************************************** + * Name: configure_mpu + * + * Description: + * This function configures the MPU for for kernel- / userspace separation. + * + ****************************************************************************/ + +static void configure_mpu(void) Review Comment: move to private section -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
