nuttx/arch/risc-v/src/mpfs/mpfs_start.c
Eero Nurkkala 8e43f39141 mpfs: cache: provide L1/L2 cache enablers
E51 may configure the L1 and L2 caches. Once configured,
no reconfiguration is possible after hardware reset is
issued.

L2 is 16-way set associative with write-back policy. The
size 2 MB, from which 1 MB is utilized with the values
provided here. That's a total of 8 ways. The rest of the
L2 is left out for the bootloader usage.

mpfs_enable_cache() first checks the bootloader usage
doesn't overlap with the cache itself, thus providing a
set of functional values.

Signed-off-by: Eero Nurkkala <eero.nurkkala@offcode.fi>
2021-11-04 11:00:55 -03:00

165 lines
4.7 KiB
C
Executable File

/****************************************************************************
* arch/risc-v/src/mpfs/mpfs_start.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 <nuttx/init.h>
#include <nuttx/arch.h>
#include <arch/board/board.h>
#include "chip.h"
#include "mpfs.h"
#include "mpfs_clockconfig.h"
#include "mpfs_ddr.h"
#include "mpfs_cache.h"
#include "mpfs_userspace.h"
#include "riscv_arch.h"
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
#ifdef CONFIG_DEBUG_FEATURES
# define showprogress(c) riscv_lowputc(c)
#else
# define showprogress(c)
#endif
/****************************************************************************
* Public Data
****************************************************************************/
/* g_idle_topstack: _sbss is the start of the BSS region as defined by the
* linker script. _ebss lies at the end of the BSS region. The idle task
* stack starts at the end of BSS and is of size CONFIG_IDLETHREAD_STACKSIZE.
* The IDLE thread is the thread that the system boots on and, eventually,
* becomes the IDLE, do nothing task that runs only when there is nothing
* else to run. The heap continues from there until the end of memory.
* g_idle_topstack is a read-only variable the provides this computed
* address.
*/
uintptr_t g_idle_topstack = MPFS_IDLESTACK_TOP;
volatile bool g_serial_ok = false;
extern void mpfs_cpu_boot(uint32_t);
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: __mpfs_start
****************************************************************************/
void __mpfs_start(uint32_t mhartid)
{
const uint32_t *src;
uint32_t *dest;
/* Clear .bss. We'll do this inline (vs. calling memset) just to be
* certain that there are no issues with the state of global variables.
*/
for (dest = &_sbss; dest < &_ebss; )
{
*dest++ = 0;
}
/* Move the initialized data section from his temporary holding spot in
* FLASH into the correct place in SRAM. The correct place in SRAM is
* give by _sdata and _edata. The temporary location is in FLASH at the
* end of all of the other read-only data (.text, .rodata) at _eronly.
*/
for (src = &_eronly, dest = &_sdata; dest < &_edata; )
{
*dest++ = *src++;
}
/* Setup PLL if not already provided */
#ifdef CONFIG_MPFS_BOOTLOADER
mpfs_clockconfig();
#endif
/* Configure the UART so we can get debug output */
mpfs_lowsetup();
showprogress('A');
#ifdef USE_EARLYSERIALINIT
riscv_earlyserialinit();
#endif
#ifdef CONFIG_MPFS_DDR_INIT
mpfs_ddr_init();
#endif
showprogress('B');
g_serial_ok = true;
/* Do board initialization */
mpfs_boardinitialize();
/* Initialize the caches. Should only be executed from E51 (hart 0) to be
* functional. Consider the caches already configured if running without
* the CONFIG_MPFS_BOOTLOADER -option.
*/
#ifdef CONFIG_MPFS_BOOTLOADER
if (mhartid == 0)
{
mpfs_enable_cache();
}
#endif
showprogress('C');
/* 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.
*/
#ifdef CONFIG_BUILD_PROTECTED
mpfs_userspace();
showprogress('D');
#endif
/* Call nx_start() */
nx_start();
showprogress('a');
while (true)
{
asm("WFI");
}
}