Files
opensbi/platform/generic/andes/ae350.c
Ben Zong-You Xie b27ecec76b lib: utils/suspend: add Andes ATCSMU suspend driver
Implement a system-wide suspend driver for the Andes AE350 platform.
This driver supports Andes-specific deep sleep (suspend to RAM) and
light sleep (suspend to standby) functionalities via the ATCSMU.

The major differences between deep sleep and light sleep are:

- Power Domain and Resume Path: Deep sleep powers down the core domain.
  Consequently, harts waking from deep sleep resume from the reset
  vector. Light sleep utilizes clock gating to the core domain; harts
  maintain state and resume execution at the instruction immediately
  following the WFI instruction.

- Primary Hart Wakeup: In both modes, the primary hart is woken by
  UART or RTC alarm interrupts. In deep sleep, the primary hart is
  additionally responsible for re-enabling the Last Level Cache (LLC)
  and restoring Andes-specific CSRs.

- Secondary Hart Wakeup: In light sleep, secondary harts are woken
  by an IPI sent from the primary hart. In deep sleep, they are
  woken by an ATCSMU hardware wake-up command. Furthermore,
  secondary harts must restore Andes-specific CSRs when returning
  from deep sleep.

Signed-off-by: Ben Zong-You Xie <ben717@andestech.com>
Signed-off-by: Leo Yu-Chi Liang <ycliang@andestech.com>
Link: https://lore.kernel.org/r/20251229071914.1451587-6-ben717@andestech.com
Signed-off-by: Anup Patel <anup@brainfault.org>
2026-02-11 12:14:04 +05:30

100 lines
3.0 KiB
C

/*
* SPDX-License-Identifier: BSD-2-Clause
*
* Copyright (c) 2025 Andes Technology Corporation
*/
#include <andes/andes.h>
#include <andes/andes_pmu.h>
#include <andes/andes_sbi.h>
#include <platform_override.h>
#include <sbi/sbi_ecall_interface.h>
#include <sbi/riscv_asm.h>
#include <sbi/sbi_init.h>
#include <sbi/sbi_scratch.h>
#include <sbi_utils/fdt/fdt_helper.h>
#include <sbi_utils/hsm/fdt_hsm_andes_atcsmu.h>
static unsigned long andes_hart_data_offset;
extern void _start_warm(void);
void ae350_non_ret_save(struct sbi_scratch *scratch)
{
struct andes_hart_data *andes_hdata = sbi_scratch_offset_ptr(scratch,
andes_hart_data_offset);
andes_hdata->mcache_ctl = csr_read(CSR_MCACHE_CTL);
andes_hdata->mmisc_ctl = csr_read(CSR_MMISC_CTL);
andes_hdata->mpft_ctl = csr_read(CSR_MPFT_CTL);
andes_hdata->mslideleg = csr_read(CSR_MSLIDELEG);
andes_hdata->mxstatus = csr_read(CSR_MXSTATUS);
andes_hdata->slie = csr_read(CSR_SLIE);
andes_hdata->slip = csr_read(CSR_SLIP);
andes_hdata->pmacfg0 = csr_read(CSR_PMACFG0);
andes_hdata->pmacfg2 = csr_read_num(CSR_PMACFG0 + 2);
for (int i = 0; i < 16; i++)
andes_hdata->pmaaddrX[i] = csr_read_num(CSR_PMAADDR0 + i);
}
void ae350_non_ret_restore(struct sbi_scratch *scratch)
{
struct andes_hart_data *andes_hdata = sbi_scratch_offset_ptr(scratch,
andes_hart_data_offset);
csr_write(CSR_MCACHE_CTL, andes_hdata->mcache_ctl);
csr_write(CSR_MMISC_CTL, andes_hdata->mmisc_ctl);
csr_write(CSR_MPFT_CTL, andes_hdata->mpft_ctl);
csr_write(CSR_MSLIDELEG, andes_hdata->mslideleg);
csr_write(CSR_MXSTATUS, andes_hdata->mxstatus);
csr_write(CSR_SLIE, andes_hdata->slie);
csr_write(CSR_SLIP, andes_hdata->slip);
csr_write(CSR_PMACFG0, andes_hdata->pmacfg0);
csr_write_num(CSR_PMACFG0 + 2, andes_hdata->pmacfg2);
for (int i = 0; i < 16; i++)
csr_write_num(CSR_PMAADDR0 + i, andes_hdata->pmaaddrX[i]);
}
void ae350_enable_coherency_warmboot(void)
{
ae350_enable_coherency();
_start_warm();
}
static int ae350_early_init(bool cold_boot)
{
u32 hartid = current_hartid();
u32 sleep_type = atcsmu_get_sleep_type(hartid);
if (cold_boot) {
andes_hart_data_offset = sbi_scratch_alloc_offset(sizeof(struct andes_hart_data));
if (!andes_hart_data_offset)
return SBI_ENOMEM;
}
/* Don't restore Andes CSRs during boot or wake up from light sleep */
if (sbi_init_count(current_hartindex()) && sleep_type == SBI_SUSP_SLEEP_TYPE_SUSPEND)
ae350_non_ret_restore(sbi_scratch_thishart_ptr());
return generic_early_init(cold_boot);
}
static int ae350_platform_init(const void *fdt, int nodeoff, const struct fdt_match *match)
{
generic_platform_ops.early_init = ae350_early_init;
generic_platform_ops.extensions_init = andes_pmu_extensions_init;
generic_platform_ops.pmu_init = andes_pmu_init;
generic_platform_ops.vendor_ext_provider = andes_sbi_vendor_ext_provider;
return 0;
}
static const struct fdt_match andes_ae350_match[] = {
{ .compatible = "andestech,ae350" },
{ },
};
const struct fdt_driver andes_ae350 = {
.match_table = andes_ae350_match,
.init = ae350_platform_init,
};