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// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright (C) 2018, Bin Meng <bmeng.cn@gmail.com>
*/
#include <common.h>
#include <cpu.h>
#include <dm.h>
#include <log.h>
#include <asm/csr.h>
#include <asm/encoding.h>
#include <dm/uclass-internal.h>
/*
* The variables here must be stored in the data section since they are used
* before the bss section is available.
*/
phys_addr_t prior_stage_fdt_address __attribute__((section(".data")));
u32 hart_lottery __attribute__((section(".data"))) = 0;
/*
* The main hart running U-Boot has acquired available_harts_lock until it has
* finished initialization of global data.
*/
u32 available_harts_lock = 1;
static inline bool supports_extension(char ext)
{
#ifdef CONFIG_CPU
struct udevice *dev;
char desc[32];
uclass_find_first_device(UCLASS_CPU, &dev);
if (!dev) {
debug("unable to find the RISC-V cpu device\n");
return false;
}
if (!cpu_get_desc(dev, desc, sizeof(desc))) {
/* skip the first 4 characters (rv32|rv64) */
if (strchr(desc + 4, ext))
return true;
}
return false;
#else /* !CONFIG_CPU */
#ifdef CONFIG_RISCV_MMODE
return csr_read(misa) & (1 << (ext - 'a'));
#else /* !CONFIG_RISCV_MMODE */
#warning "There is no way to determine the available extensions in S-mode."
#warning "Please convert your board to use the RISC-V CPU driver."
return false;
#endif /* CONFIG_RISCV_MMODE */
#endif /* CONFIG_CPU */
}
static int riscv_cpu_probe(void)
{
#ifdef CONFIG_CPU
int ret;
/* probe cpus so that RISC-V timer can be bound */
ret = cpu_probe_all();
if (ret)
return log_msg_ret("RISC-V cpus probe failed\n", ret);
#endif
return 0;
}
int arch_cpu_init_dm(void)
{
int ret;
ret = riscv_cpu_probe();
if (ret)
return ret;
/* Enable FPU */
if (supports_extension('d') || supports_extension('f')) {
csr_set(MODE_PREFIX(status), MSTATUS_FS);
csr_write(fcsr, 0);
}
if (CONFIG_IS_ENABLED(RISCV_MMODE)) {
/*
* Enable perf counters for cycle, time,
* and instret counters only
*/
csr_write(mcounteren, GENMASK(2, 0));
/* Disable paging */
if (supports_extension('s'))
csr_write(satp, 0);
}
return 0;
}
int arch_early_init_r(void)
{
return riscv_cpu_probe();
}
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