diff options
| -rw-r--r-- | include/sbi_utils/timer/aclint_mtimer.h | 41 | ||||
| -rw-r--r-- | lib/utils/timer/aclint_mtimer.c | 180 | ||||
| -rw-r--r-- | lib/utils/timer/objects.mk | 1 |
3 files changed, 222 insertions, 0 deletions
diff --git a/include/sbi_utils/timer/aclint_mtimer.h b/include/sbi_utils/timer/aclint_mtimer.h new file mode 100644 index 0000000..62aa086 --- /dev/null +++ b/include/sbi_utils/timer/aclint_mtimer.h @@ -0,0 +1,41 @@ +/* + * SPDX-License-Identifier: BSD-2-Clause + * + * Copyright (c) 2021 Western Digital Corporation or its affiliates. + * + * Authors: + * Anup Patel <anup.patel@wdc.com> + */ + +#ifndef __TIMER_ACLINT_MTIMER_H__ +#define __TIMER_ACLINT_MTIMER_H__ + +#include <sbi/sbi_types.h> + +#define ACLINT_MTIMER_ALIGN 0x1000 +#define ACLINT_MTIMER_SIZE 0x8000 +#define ACLINT_MTIMER_MAX_HARTS 4095 + +#define CLINT_MTIMER_OFFSET 0x4000 + +struct aclint_mtimer_data { + /* Public details */ + unsigned long addr; + unsigned long size; + u32 first_hartid; + u32 hart_count; + bool has_64bit_mmio; + /* Private details (initialized and used by ACLINT MTIMER library) */ + struct aclint_mtimer_data *time_delta_reference; + unsigned long time_delta_computed; + u64 time_delta; + u64 (*time_rd)(volatile u64 *addr); + void (*time_wr)(bool timecmp, u64 value, volatile u64 *addr); +}; + +int aclint_mtimer_warm_init(void); + +int aclint_mtimer_cold_init(struct aclint_mtimer_data *mt, + struct aclint_mtimer_data *reference); + +#endif diff --git a/lib/utils/timer/aclint_mtimer.c b/lib/utils/timer/aclint_mtimer.c new file mode 100644 index 0000000..41b0290 --- /dev/null +++ b/lib/utils/timer/aclint_mtimer.c @@ -0,0 +1,180 @@ +/* + * SPDX-License-Identifier: BSD-2-Clause + * + * Copyright (c) 2021 Western Digital Corporation or its affiliates. + * + * Authors: + * Anup Patel <anup.patel@wdc.com> + */ + +#include <sbi/riscv_asm.h> +#include <sbi/riscv_atomic.h> +#include <sbi/riscv_io.h> +#include <sbi/sbi_domain.h> +#include <sbi/sbi_error.h> +#include <sbi/sbi_hartmask.h> +#include <sbi/sbi_ipi.h> +#include <sbi/sbi_timer.h> +#include <sbi_utils/timer/aclint_mtimer.h> + +#define MTIMER_CMP_OFF 0x0000 +#define MTIMER_VAL_OFF 0x7ff8 + +static struct aclint_mtimer_data *mtimer_hartid2data[SBI_HARTMASK_MAX_BITS]; + +#if __riscv_xlen != 32 +static u64 mtimer_time_rd64(volatile u64 *addr) +{ + return readq_relaxed(addr); +} + +static void mtimer_time_wr64(bool timecmp, u64 value, volatile u64 *addr) +{ + writeq_relaxed(value, addr); +} +#endif + +static u64 mtimer_time_rd32(volatile u64 *addr) +{ + u32 lo, hi; + + do { + hi = readl_relaxed((u32 *)addr + 1); + lo = readl_relaxed((u32 *)addr); + } while (hi != readl_relaxed((u32 *)addr + 1)); + + return ((u64)hi << 32) | (u64)lo; +} + +static void mtimer_time_wr32(bool timecmp, u64 value, volatile u64 *addr) +{ + writel_relaxed((timecmp) ? -1U : 0U, (void *)(addr)); + writel_relaxed((u32)(value >> 32), (void *)(addr) + 0x04); + writel_relaxed((u32)value, (void *)(addr)); +} + +static u64 mtimer_value(void) +{ + struct aclint_mtimer_data *mt = mtimer_hartid2data[current_hartid()]; + u64 *time_val = ((void *)mt->addr) + MTIMER_VAL_OFF; + + /* Read MTIMER Time Value */ + return mt->time_rd(time_val) + mt->time_delta; +} + +static void mtimer_event_stop(void) +{ + u32 target_hart = current_hartid(); + struct aclint_mtimer_data *mt = mtimer_hartid2data[target_hart]; + u64 *time_cmp = (void *)mt->addr + MTIMER_CMP_OFF; + + /* Clear MTIMER Time Compare */ + mt->time_wr(true, -1ULL, &time_cmp[target_hart - mt->first_hartid]); +} + +static void mtimer_event_start(u64 next_event) +{ + u32 target_hart = current_hartid(); + struct aclint_mtimer_data *mt = mtimer_hartid2data[target_hart]; + u64 *time_cmp = (void *)mt->addr + MTIMER_CMP_OFF; + + /* Program MTIMER Time Compare */ + mt->time_wr(true, next_event - mt->time_delta, + &time_cmp[target_hart - mt->first_hartid]); +} + +static struct sbi_timer_device mtimer = { + .name = "aclint-mtimer", + .timer_value = mtimer_value, + .timer_event_start = mtimer_event_start, + .timer_event_stop = mtimer_event_stop +}; + +int aclint_mtimer_warm_init(void) +{ + u64 v1, v2, mv; + u32 target_hart = current_hartid(); + struct aclint_mtimer_data *reference; + u64 *mt_time_val, *mt_time_cmp, *ref_time_val; + struct aclint_mtimer_data *mt = mtimer_hartid2data[target_hart]; + + if (!mt) + return SBI_ENODEV; + + /* + * Compute delta if reference available + * + * We deliberately compute time_delta in warm init so that time_delta + * is computed on a HART which is going to use given MTIMER. We use + * atomic flag timer_delta_computed to ensure that only one HART does + * time_delta computation. + */ + if (mt->time_delta_reference) { + reference = mt->time_delta_reference; + mt_time_val = (void *)mt->addr + MTIMER_VAL_OFF; + ref_time_val = (void *)reference->addr + MTIMER_VAL_OFF; + if (!atomic_raw_xchg_ulong(&mt->time_delta_computed, 1)) { + v1 = mt->time_rd(mt_time_val); + mv = reference->time_rd(ref_time_val); + v2 = mt->time_rd(mt_time_val); + mt->time_delta = mv - ((v1 / 2) + (v2 / 2)); + } + } + + /* Clear Time Compare */ + mt_time_cmp = (void *)mt->addr + MTIMER_CMP_OFF; + mt->time_wr(true, -1ULL, + &mt_time_cmp[target_hart - mt->first_hartid]); + + return 0; +} + +int aclint_mtimer_cold_init(struct aclint_mtimer_data *mt, + struct aclint_mtimer_data *reference) +{ + u32 i; + int rc; + unsigned long pos, region_size; + struct sbi_domain_memregion reg; + + /* Sanity checks */ + if (!mt || (mt->addr & (ACLINT_MTIMER_ALIGN - 1)) || + (mt->size < ACLINT_MTIMER_SIZE) || + (mt->first_hartid >= SBI_HARTMASK_MAX_BITS) || + (mt->hart_count > ACLINT_MTIMER_MAX_HARTS)) + return SBI_EINVAL; + + /* Initialize private data */ + mt->time_delta_reference = reference; + mt->time_delta_computed = 0; + mt->time_delta = 0; + mt->time_rd = mtimer_time_rd32; + mt->time_wr = mtimer_time_wr32; + + /* Override read/write accessors for 64bit MMIO */ +#if __riscv_xlen != 32 + if (mt->has_64bit_mmio) { + mt->time_rd = mtimer_time_rd64; + mt->time_wr = mtimer_time_wr64; + } +#endif + + /* Update MTIMER hartid table */ + for (i = 0; i < mt->hart_count; i++) + mtimer_hartid2data[mt->first_hartid + i] = mt; + + /* Add MTIMER regions to the root domain */ + for (pos = 0; pos < mt->size; pos += ACLINT_MTIMER_ALIGN) { + region_size = ((mt->size - pos) < ACLINT_MTIMER_ALIGN) ? + (mt->size - pos) : ACLINT_MTIMER_ALIGN; + sbi_domain_memregion_init(mt->addr + pos, region_size, + SBI_DOMAIN_MEMREGION_MMIO, ®); + rc = sbi_domain_root_add_memregion(®); + if (rc) + return rc; + } + + sbi_timer_set_device(&mtimer); + + return 0; +} diff --git a/lib/utils/timer/objects.mk b/lib/utils/timer/objects.mk index 1b84e92..1d8b1e5 100644 --- a/lib/utils/timer/objects.mk +++ b/lib/utils/timer/objects.mk @@ -7,5 +7,6 @@ # Anup Patel <anup.patel@wdc.com> # +libsbiutils-objs-y += timer/aclint_mtimer.o libsbiutils-objs-y += timer/fdt_timer.o libsbiutils-objs-y += timer/fdt_timer_clint.o |