u-boot/arch/riscv/cpu/fu740/spl.c
Green Wan c552debbd8 riscv: cpu: fu740: clear feature disable CSR
Clear feature disable CSR to turn on all features of hart. The detail
is specified at section, 'SiFive Feature Disable CSR', in user manual

https://sifive.cdn.prismic.io/sifive/aee0dd4c-d156-496e-a6c4-db0cf54bbe68_sifive_U74MC_rtl_full_20G1.03.00_manual.pdf

Signed-off-by: Green Wan <green.wan@sifive.com>
Reviewed-by: Sean Anderson <seanga2@gmail.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Rick Chen <rick@andestech.com>
2021-05-31 16:35:55 +08:00

38 lines
689 B
C

// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright (C) 2020-201 SiFive, Inc
* Pragnesh Patel <pragnesh.patel@sifive.com>
*/
#include <dm.h>
#include <log.h>
#include <asm/csr.h>
#define CSR_U74_FEATURE_DISABLE 0x7c1
int spl_soc_init(void)
{
int ret;
struct udevice *dev;
/* DDR init */
ret = uclass_get_device(UCLASS_RAM, 0, &dev);
if (ret) {
debug("DRAM init failed: %d\n", ret);
return ret;
}
return 0;
}
void harts_early_init(void)
{
/*
* Feature Disable CSR
*
* Clear feature disable CSR to '0' to turn on all features for
* each core. This operation must be in M-mode.
*/
if (CONFIG_IS_ENABLED(RISCV_MMODE))
csr_write(CSR_U74_FEATURE_DISABLE, 0);
}