| // SPDX-License-Identifier: GPL-2.0+ |
| /* |
| * Copyright (C) 2019, Rick Chen <rick@andestech.com> |
| * Copyright (C) 2020, Sean Anderson <seanga2@gmail.com> |
| * |
| * U-Boot syscon driver for Andes's Platform Level Machine Timer (PLMT). |
| * The PLMT block holds memory-mapped mtime register |
| * associated with timer tick. |
| */ |
| |
| #include <common.h> |
| #include <dm.h> |
| #include <timer.h> |
| #include <asm/io.h> |
| #include <dm/device-internal.h> |
| #include <linux/err.h> |
| |
| /* mtime register */ |
| #define MTIME_REG(base) ((ulong)(base)) |
| |
| static u64 notrace andes_plmt_get_count(struct udevice *dev) |
| { |
| return readq((void __iomem *)MTIME_REG(dev_get_priv(dev))); |
| } |
| |
| #if CONFIG_IS_ENABLED(RISCV_MMODE) && IS_ENABLED(CONFIG_TIMER_EARLY) |
| /** |
| * timer_early_get_rate() - Get the timer rate before driver model |
| */ |
| unsigned long notrace timer_early_get_rate(void) |
| { |
| return RISCV_MMODE_TIMER_FREQ; |
| } |
| |
| /** |
| * timer_early_get_count() - Get the timer count before driver model |
| * |
| */ |
| u64 notrace timer_early_get_count(void) |
| { |
| return readq((void __iomem *)MTIME_REG(RISCV_MMODE_TIMERBASE)); |
| } |
| #endif |
| |
| static const struct timer_ops andes_plmt_ops = { |
| .get_count = andes_plmt_get_count, |
| }; |
| |
| static int andes_plmt_probe(struct udevice *dev) |
| { |
| dev_set_priv(dev, dev_read_addr_ptr(dev)); |
| if (!dev_get_priv(dev)) |
| return -EINVAL; |
| |
| return timer_timebase_fallback(dev); |
| } |
| |
| static const struct udevice_id andes_plmt_ids[] = { |
| { .compatible = "riscv,plmt0" }, |
| { } |
| }; |
| |
| U_BOOT_DRIVER(andes_plmt) = { |
| .name = "andes_plmt", |
| .id = UCLASS_TIMER, |
| .of_match = andes_plmt_ids, |
| .ops = &andes_plmt_ops, |
| .probe = andes_plmt_probe, |
| .flags = DM_FLAG_PRE_RELOC, |
| }; |