1 // SPDX-License-Identifier: GPL-2.0+ 2 /* 3 * Copyright (C) 2017, STMicroelectronics - All Rights Reserved 4 * Author(s): Patrice Chotard, <patrice.chotard@st.com> for STMicroelectronics. 5 */ 6 7 #include <common.h> 8 #include <dm.h> 9 #include <fdtdec.h> 10 #include <timer.h> 11 12 #include <asm/io.h> 13 #include <asm/arch-armv7/globaltimer.h> 14 15 DECLARE_GLOBAL_DATA_PTR; 16 17 struct sti_timer_priv { 18 struct globaltimer *global_timer; 19 }; 20 21 static int sti_timer_get_count(struct udevice *dev, u64 *count) 22 { 23 struct sti_timer_priv *priv = dev_get_priv(dev); 24 struct globaltimer *global_timer = priv->global_timer; 25 u32 low, high; 26 u64 timer; 27 u32 old = readl(&global_timer->cnt_h); 28 29 while (1) { 30 low = readl(&global_timer->cnt_l); 31 high = readl(&global_timer->cnt_h); 32 if (old == high) 33 break; 34 else 35 old = high; 36 } 37 timer = high; 38 *count = (u64)((timer << 32) | low); 39 40 return 0; 41 } 42 43 static int sti_timer_probe(struct udevice *dev) 44 { 45 struct timer_dev_priv *uc_priv = dev_get_uclass_priv(dev); 46 struct sti_timer_priv *priv = dev_get_priv(dev); 47 fdt_addr_t addr; 48 49 uc_priv->clock_rate = CONFIG_SYS_HZ_CLOCK; 50 51 /* get arm global timer base address */ 52 addr = fdtdec_get_addr(gd->fdt_blob, dev_of_offset(dev), "reg"); 53 priv->global_timer = (struct globaltimer *)addr; 54 55 /* init timer */ 56 writel(0x01, &priv->global_timer->ctl); 57 58 return 0; 59 } 60 61 static const struct timer_ops sti_timer_ops = { 62 .get_count = sti_timer_get_count, 63 }; 64 65 static const struct udevice_id sti_timer_ids[] = { 66 { .compatible = "arm,cortex-a9-global-timer" }, 67 {} 68 }; 69 70 U_BOOT_DRIVER(sti_timer) = { 71 .name = "sti_timer", 72 .id = UCLASS_TIMER, 73 .of_match = sti_timer_ids, 74 .priv_auto_alloc_size = sizeof(struct sti_timer_priv), 75 .probe = sti_timer_probe, 76 .ops = &sti_timer_ops, 77 }; 78