xil_mpu.c 20.3 KB
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/******************************************************************************
*
* Copyright (C) 2014 - 2017 Xilinx, Inc. All rights reserved.
* Copyright (C) 2021 WangHuachen. All rights reserved.
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*
*
*
******************************************************************************/
/*****************************************************************************/
/**
* @file xil_mpu.c
*
* This file provides APIs for enabling/disabling MPU and setting the memory
* attributes for sections, in the MPU translation table.
*
* <pre>
* MODIFICATION HISTORY:
*
* Ver   Who  Date     Changes
* ----- ---- -------- ---------------------------------------------------
* 5.00  pkp  02/10/14 Initial version
* 6.2   mus  01/27/17 Updated to support IAR compiler
* 6.4   asa  08/16/17 Added many APIs for MPU access to make MPU usage
*                       user-friendly. The APIs added are: Xil_UpdateMPUConfig,
*                       Xil_GetMPUConfig, Xil_GetNumOfFreeRegions,
*                       Xil_GetNextMPURegion, Xil_DisableMPURegionByRegNum,
*                       Xil_GetMPUFreeRegMask, Xil_SetMPURegionByRegNum, and
*                       Xil_InitializeExistingMPURegConfig.
*                       Added a new array of structure of type XMpuConfig to
*                       represent the MPU configuration table.
* 6.8  aru  07/02/18 Returned the pointer instead of address
*            of that pointer in Xil_MemMap().
* </pre>
*
*
******************************************************************************/

/***************************** Include Files *********************************/

#include "xil_cache.h"
#include "xpseudo_asm_gcc.h"
#include "xil_types.h"
#include "xil_mpu.h"
// #include "xdebug.h"
#include "xreg_cortexr5.h"
#include "xstatus.h"

#include <rtthread.h>
#define DBG_TAG           "xil_mpu"
#define DBG_LVL           DBG_INFO
#include <rtdbg.h>

extern void Xil_DCacheFlush(void);
extern void Xil_ICacheInvalidate(void);
extern void Xil_DCacheDisable(void);
extern void Xil_ICacheDisable(void);
extern void Xil_DCacheEnable(void);
extern void Xil_ICacheEnable(void);

/***************** Macros (Inline Functions) Definitions *********************/

/**************************** Type Definitions *******************************/

/************************** Constant Definitions *****************************/
#define MPU_REGION_SIZE_MIN 0x20
/************************** Variable Definitions *****************************/

static const struct {
    u64 size;
    unsigned int encoding;
}region_size[] = {
    { 0x20, REGION_32B },
    { 0x40, REGION_64B },
    { 0x80, REGION_128B },
    { 0x100, REGION_256B },
    { 0x200, REGION_512B },
    { 0x400, REGION_1K },
    { 0x800, REGION_2K },
    { 0x1000, REGION_4K },
    { 0x2000, REGION_8K },
    { 0x4000, REGION_16K },
    { 0x8000, REGION_32K },
    { 0x10000, REGION_64K },
    { 0x20000, REGION_128K },
    { 0x40000, REGION_256K },
    { 0x80000, REGION_512K },
    { 0x100000, REGION_1M },
    { 0x200000, REGION_2M },
    { 0x400000, REGION_4M },
    { 0x800000, REGION_8M },
    { 0x1000000, REGION_16M },
    { 0x2000000, REGION_32M },
    { 0x4000000, REGION_64M },
    { 0x8000000, REGION_128M },
    { 0x10000000, REGION_256M },
    { 0x20000000, REGION_512M },
    { 0x40000000, REGION_1G },
    { 0x80000000, REGION_2G },
    { 0x100000000, REGION_4G },
};

XMpu_Config Mpu_Config;

/************************** Function Prototypes ******************************/
void Xil_InitializeExistingMPURegConfig(void);
/*****************************************************************************/
/**
* @brief    This function sets the memory attributes for a section covering
*           1MB, of memory in the translation table.
*
* @param    Addr: 32-bit address for which memory attributes need to be set.
* @param    attrib: Attribute for the given memory region.
* @return    None.
*
*
******************************************************************************/
void Xil_SetTlbAttributes(INTPTR addr, u32 attrib)
{
    INTPTR Localaddr = addr;
    Localaddr &= (~(0xFFFFFU));
    /* Setting the MPU region with given attribute with 1MB size */
    Xil_SetMPURegion(Localaddr, 0x100000, attrib);
}

/*****************************************************************************/
/**
* @brief    Set the memory attributes for a section of memory in the
*           translation table.
*
* @param    Addr: 32-bit address for which memory attributes need to be set..
* @param    size: size is the size of the region.
* @param    attrib: Attribute for the given memory region.
* @return    None.
*
*
******************************************************************************/
u32 Xil_SetMPURegion(INTPTR addr, u64 size, u32 attrib)
{
    u32 Regionsize = 0;
    INTPTR Localaddr = addr;
    u32 NextAvailableMemRegion;
    unsigned int i;

    NextAvailableMemRegion = Xil_GetNextMPURegion();
    if (NextAvailableMemRegion == 0xFF) {
        LOG_E("No regions available\r\n");
        return XST_FAILURE;
    }

    Xil_DCacheFlush();
    Xil_ICacheInvalidate();

    mtcp(XREG_CP15_MPU_MEMORY_REG_NUMBER,NextAvailableMemRegion);
    isb();

    /* Lookup the size.  */
    for (i = 0; i < sizeof region_size / sizeof region_size[0]; i++) {
        if (size <= region_size[i].size) {
            Regionsize = region_size[i].encoding;
            break;
        }
    }

    Localaddr &= ~(region_size[i].size - 1);

    Regionsize <<= 1;
    Regionsize |= REGION_EN;
    dsb();
    mtcp(XREG_CP15_MPU_REG_BASEADDR, Localaddr);    /* Set base address of a region */
    mtcp(XREG_CP15_MPU_REG_ACCESS_CTRL, attrib);    /* Set the control attribute */
    mtcp(XREG_CP15_MPU_REG_SIZE_EN, Regionsize);    /* set the region size and enable it*/
    dsb();
    isb();
    Xil_UpdateMPUConfig(NextAvailableMemRegion, Localaddr, Regionsize, attrib);
    return XST_SUCCESS;
}
/*****************************************************************************/
/**
* @brief    Enable MPU for Cortex R5 processor. This function invalidates I
*           cache and flush the D Caches, and then enables the MPU.
*
*
* @param    None.
* @return    None.
*
******************************************************************************/
void Xil_EnableMPU(void)
{
    u32 CtrlReg, Reg;
    s32 DCacheStatus=0, ICacheStatus=0;
    /* enable caches only if they are disabled */
#if defined (__GNUC__)
    CtrlReg = mfcp(XREG_CP15_SYS_CONTROL);
#elif defined (__ICCARM__)
    mfcp(XREG_CP15_SYS_CONTROL,CtrlReg);
#endif
    if ((CtrlReg & XREG_CP15_CONTROL_C_BIT) != 0x00000000U) {
        DCacheStatus=1;
    }
    if ((CtrlReg & XREG_CP15_CONTROL_I_BIT) != 0x00000000U) {
        ICacheStatus=1;
    }

    if(DCacheStatus != 0) {
        Xil_DCacheDisable();
    }
    if(ICacheStatus != 0){
        Xil_ICacheDisable();
    }
#if defined (__GNUC__)
    Reg = mfcp(XREG_CP15_SYS_CONTROL);
#elif defined (__ICCARM__)
     mfcp(XREG_CP15_SYS_CONTROL,Reg);
#endif
    Reg |= 0x00000001U;
    dsb();
    mtcp(XREG_CP15_SYS_CONTROL, Reg);
    isb();
    /* enable caches only if they are disabled in routine*/
    if(DCacheStatus != 0) {
        Xil_DCacheEnable();
    }
    if(ICacheStatus != 0) {
        Xil_ICacheEnable();
    }
}

/*****************************************************************************/
/**
* @brief    Disable MPU for Cortex R5 processors. This function invalidates I
*           cache and flush the D Caches, and then disabes the MPU.
*
* @param    None.
*
* @return    None.
*
******************************************************************************/
void Xil_DisableMPU(void)
{
    u32 CtrlReg, Reg;
    s32 DCacheStatus=0, ICacheStatus=0;
    /* enable caches only if they are disabled */

#if defined (__GNUC__)
    CtrlReg = mfcp(XREG_CP15_SYS_CONTROL);
#elif defined (__ICCARM__)
    mfcp(XREG_CP15_SYS_CONTROL,CtrlReg);
#endif
    if ((CtrlReg & XREG_CP15_CONTROL_C_BIT) != 0x00000000U) {
        DCacheStatus=1;
    }
    if ((CtrlReg & XREG_CP15_CONTROL_I_BIT) != 0x00000000U) {
        ICacheStatus=1;
    }

    if(DCacheStatus != 0) {
        Xil_DCacheDisable();
    }
    if(ICacheStatus != 0){
        Xil_ICacheDisable();
    }

    mtcp(XREG_CP15_INVAL_BRANCH_ARRAY, 0);
#if defined (__GNUC__)
    Reg = mfcp(XREG_CP15_SYS_CONTROL);
#elif defined (__ICCARM__)
    mfcp(XREG_CP15_SYS_CONTROL,Reg);
#endif
    Reg &= ~(0x00000001U);
    dsb();
    mtcp(XREG_CP15_SYS_CONTROL, Reg);
    isb();
    /* enable caches only if they are disabled in routine*/
    if(DCacheStatus != 0) {
        Xil_DCacheEnable();
    }
    if(ICacheStatus != 0) {
        Xil_ICacheEnable();
    }
}

/*****************************************************************************/
/**
* @brief    Update the MPU configuration for the requested region number in
*             the global MPU configuration table.
*
* @param    reg_num: The requested region number to be updated information for.
* @param    address: 32 bit address for start of the region.
* @param    size: Requested size of the region.
* @param    attrib: Attribute for the corresponding region.
* @return    XST_FAILURE: When the requested region number if 16 or more.
*             XST_SUCCESS: When the MPU configuration table is updated.
*
*
******************************************************************************/
u32 Xil_UpdateMPUConfig(u32 reg_num, INTPTR address, u32 size, u32 attrib)
{
    u32 ReturnVal = XST_SUCCESS;
    u32 Tempsize = size;
    u32 Index;

    if (reg_num >=  MAX_POSSIBLE_MPU_REGS) {
        LOG_E("Invalid region number\r\n");
        ReturnVal = XST_FAILURE;
        goto exit;
    }

    if (size & REGION_EN) {
        Mpu_Config[reg_num].RegionStatus = MPU_REG_ENABLED;
        Mpu_Config[reg_num].BaseAddress = address;
        Tempsize &= (~REGION_EN);
        Tempsize >>= 1;
        /* Lookup the size.  */
        for (Index = 0; Index <
                sizeof region_size / sizeof region_size[0]; Index++) {
            if (Tempsize <= region_size[Index].encoding) {
                Mpu_Config[reg_num].Size = region_size[Index].size;
                break;
            }
        }
        Mpu_Config[reg_num].Attribute = attrib;
    } else {
        Mpu_Config[reg_num].RegionStatus = 0U;
        Mpu_Config[reg_num].BaseAddress = 0U;
        Mpu_Config[reg_num].Size = 0U;
        Mpu_Config[reg_num].Attribute = 0U;
    }

exit:
    return ReturnVal;
}

/*****************************************************************************/
/**
* @brief    The MPU configuration table is passed to the caller.
*
* @param    mpuconfig: This is of type XMpu_Config which is an array of
*             16 entries of type structure representing the MPU config table
* @return    none
*
*
******************************************************************************/
void Xil_GetMPUConfig (XMpu_Config mpuconfig) {
    u32 Index = 0U;

    while (Index < MAX_POSSIBLE_MPU_REGS) {
        mpuconfig[Index].RegionStatus = Mpu_Config[Index].RegionStatus;
        mpuconfig[Index].BaseAddress = Mpu_Config[Index].BaseAddress;
        mpuconfig[Index].Attribute = Mpu_Config[Index].Attribute;
        mpuconfig[Index].Size = Mpu_Config[Index].Size;
        Index++;
    }
}

/*****************************************************************************/
/**
* @brief    Returns the total number of free MPU regions available.
*
* @param    none
* @return    Number of free regions available to users
*
*
******************************************************************************/
u32 Xil_GetNumOfFreeRegions (void) {
    u32 Index = 0U;
    int NumofFreeRegs = 0U;

    while (Index < MAX_POSSIBLE_MPU_REGS) {
        if (MPU_REG_DISABLED == Mpu_Config[Index].RegionStatus) {
            NumofFreeRegs++;
        }
        Index++;
    }
    return NumofFreeRegs;
}

/*****************************************************************************/
/**
* @brief    Returns the total number of free MPU regions available in the form
*           of a mask. A bit of 1 in the returned 16 bit value represents the
*           corresponding region number to be available.
*           For example, if this function returns 0xC0000, this would mean, the
*           regions 14 and 15 are available to users.
*
* @param    none
* @return    The free region mask as a 16 bit value
*
*
******************************************************************************/
u16 Xil_GetMPUFreeRegMask (void) {
    u32 Index = 0U;
    u16 FreeRegMask = 0U;

    while (Index < MAX_POSSIBLE_MPU_REGS) {
        if (MPU_REG_DISABLED == Mpu_Config[Index].RegionStatus) {
            FreeRegMask |= (1U << Index);
        }
        Index++;
    }
    return FreeRegMask;
}

/*****************************************************************************/
/**
* @brief    Disables the corresponding region number as passed by the user.
*
* @param    reg_num: The region number to be disabled
* @return    XST_SUCCESS: If the region could be disabled successfully
*             XST_FAILURE: If the requested region number is 16 or more.
*
*
******************************************************************************/
u32 Xil_DisableMPURegionByRegNum (u32 reg_num) {
    u32 Temp = 0U;
    u32 ReturnVal = XST_FAILURE;

    if (reg_num >= 16U) {
        LOG_E("Invalid region number\r\n");
        goto exit1;
    }
    Xil_DCacheFlush();
    Xil_ICacheInvalidate();

    mtcp(XREG_CP15_MPU_MEMORY_REG_NUMBER,reg_num);
#if defined (__GNUC__)
    Temp = mfcp(XREG_CP15_MPU_REG_SIZE_EN);
#elif defined (__ICCARM__)
    mfcp(XREG_CP15_MPU_REG_SIZE_EN,Temp);
#endif
    Temp &= (~REGION_EN);
    dsb();
    mtcp(XREG_CP15_MPU_REG_SIZE_EN,Temp);
    dsb();
    isb();
    Xil_UpdateMPUConfig(reg_num, 0U, 0U, 0U);
    ReturnVal = XST_SUCCESS;

exit1:
    return ReturnVal;
}

/*****************************************************************************/
/**
* @brief    Enables the corresponding region number as passed by the user.
*
* @param    reg_num: The region number to be enabled
* @param    address: 32 bit address for start of the region.
* @param    size: Requested size of the region.
* @param    attrib: Attribute for the corresponding region.
* @return    XST_SUCCESS: If the region could be created successfully
*             XST_FAILURE: If the requested region number is 16 or more.
*
*
******************************************************************************/
u32 Xil_SetMPURegionByRegNum (u32 reg_num, INTPTR addr, u64 size, u32 attrib)
{
    u32 ReturnVal = XST_SUCCESS;
    INTPTR Localaddr = addr;
    u32 Regionsize = 0;
    u32 Index;

    if (reg_num >= 16U) {
        LOG_E("Invalid region number\r\n");
        ReturnVal = XST_FAILURE;
        goto exit2;
    }

    if (Mpu_Config[reg_num].RegionStatus == MPU_REG_ENABLED) {
        LOG_E("Region already enabled\r\n");
        ReturnVal = XST_FAILURE;
        goto exit2;
    }

    Xil_DCacheFlush();
    Xil_ICacheInvalidate();
    mtcp(XREG_CP15_MPU_MEMORY_REG_NUMBER,reg_num);
    isb();

    /* Lookup the size.  */
    for (Index = 0; Index <
            sizeof region_size / sizeof region_size[0]; Index++) {
        if (size <= region_size[Index].size) {
            Regionsize = region_size[Index].encoding;
            break;
        }
    }

    Localaddr &= ~(region_size[Index].size - 1);
    Regionsize <<= 1;
    Regionsize |= REGION_EN;
    dsb();
    mtcp(XREG_CP15_MPU_REG_BASEADDR, Localaddr);
    mtcp(XREG_CP15_MPU_REG_ACCESS_CTRL, attrib);
    mtcp(XREG_CP15_MPU_REG_SIZE_EN, Regionsize);
    dsb();
    isb();
    Xil_UpdateMPUConfig(reg_num, Localaddr, Regionsize, attrib);
exit2:
    return ReturnVal;

}

/*****************************************************************************/
/**
* @brief    Initializes the MPU configuration table that are setup in the
*             R5 boot code in the Init_Mpu function called before C main.
*
* @param    none
* @return    none
*
*
******************************************************************************/
void Xil_InitializeExistingMPURegConfig(void)
{
    u32 Index = 0U;
    u32 Index1 = 0U;
    u32 MPURegSize;
    INTPTR MPURegBA;
    u32 MPURegAttrib;
    u32 Tempsize;

    while (Index < MAX_POSSIBLE_MPU_REGS) {
        mtcp(XREG_CP15_MPU_MEMORY_REG_NUMBER,Index);
#if defined (__GNUC__)
        MPURegSize = mfcp(XREG_CP15_MPU_REG_SIZE_EN);
        MPURegBA = mfcp(XREG_CP15_MPU_REG_BASEADDR);
        MPURegAttrib = mfcp(XREG_CP15_MPU_REG_ACCESS_CTRL);
#elif defined (__ICCARM__)
        mfcp(XREG_CP15_MPU_REG_SIZE_EN,MPURegSize);
        mfcp(XREG_CP15_MPU_REG_BASEADDR, MPURegBA);
        mfcp(XREG_CP15_MPU_REG_ACCESS_CTRL, MPURegAttrib);
#endif
        if (MPURegSize & REGION_EN) {
            Mpu_Config[Index].RegionStatus = MPU_REG_ENABLED;
            Mpu_Config[Index].BaseAddress = MPURegBA;
            Mpu_Config[Index].Attribute = MPURegAttrib;
            Tempsize = MPURegSize & (~REGION_EN);
            Tempsize >>= 1;
            for (Index1 = 0; Index1 <
                (sizeof (region_size) / sizeof (region_size[0])); Index1++) {
                if (Tempsize <= region_size[Index1].encoding) {
                    Mpu_Config[Index].Size = region_size[Index1].size;
                    break;
                }
            }
        }
        Index++;
    }
}

/*****************************************************************************/
/**
* @brief    Returns the next available free MPU region
*
* @param    none
* @return    The free MPU region available
*
*
******************************************************************************/
u32 Xil_GetNextMPURegion(void)
{
    u32 Index = 0U;
    u32 NextAvailableReg = 0xFF;
    while (Index < MAX_POSSIBLE_MPU_REGS) {
        if (Mpu_Config[Index].RegionStatus != MPU_REG_ENABLED) {
            NextAvailableReg = Index;
            break;
        }
        Index++;
    }
    return NextAvailableReg;
}

/*****************************************************************************/
/**
* @brief       Memory mapping for Cortex r5.
*
* @param       Physaddr is base physical address at which to start mapping.
*                   NULL in Physaddr masks possible mapping errors.
* @param       size of region to be mapped.
* @param       flags used to set translation table.
*
* @return      Physaddr on success, NULL on error. Ambiguous if Physaddr==NULL
*
* @note:    u32overflow() is defined for readability and (for __GNUC__) to
*           - force the type of the check to be the same as the first argument
*           - hide the otherwise unused third argument of the builtin
*           - improve safety by choosing the explicit _uadd_ version.
*           Consider __builtin_add_overflow_p() when available.
*           Use an alternative (less optimal?) for compilers w/o the builtin.
*
******************************************************************************/
#ifdef __GNUC__
#define u32overflow(a, b) ({typeof(a) s; __builtin_uadd_overflow(a, b, &s); })
#else
#define u32overflow(a, b) ((a) > ((a) + (b)))
#endif /* __GNUC__ */
void *Xil_MemMap(UINTPTR Physaddr, size_t size, u32 flags)
{
    size_t Regionsize = MPU_REGION_SIZE_MIN;
    UINTPTR Basephysaddr = 0, end = Physaddr + size;

    if (!flags)
        return (void *)Physaddr;
    if (u32overflow(Physaddr, size))
        return NULL;
    for ( ; Regionsize != 0; Regionsize <<= 1) {
        if (Regionsize >= size) {
            Basephysaddr = Physaddr & ~(Regionsize - 1);
            if (u32overflow(Basephysaddr, Regionsize))
                break;
            if ((Basephysaddr + Regionsize) >= end)
                return Xil_SetMPURegion(Basephysaddr,
                    Regionsize, flags) == XST_SUCCESS ?
                    (void *)Physaddr : NULL;
        }
    }
    return NULL;
}