1 /* 2 * TI OMAP timer driver 3 * 4 * Copyright (C) 2015, Texas Instruments, Incorporated 5 * 6 * SPDX-License-Identifier: GPL-2.0+ 7 */ 8 9 #include <common.h> 10 #include <dm.h> 11 #include <errno.h> 12 #include <timer.h> 13 #include <asm/io.h> 14 #include <asm/arch/clock.h> 15 16 /* Timer register bits */ 17 #define TCLR_START BIT(0) /* Start=1 */ 18 #define TCLR_AUTO_RELOAD BIT(1) /* Auto reload */ 19 #define TCLR_PRE_EN BIT(5) /* Pre-scaler enable */ 20 #define TCLR_PTV_SHIFT (2) /* Pre-scaler shift value */ 21 22 #define TIMER_CLOCK (V_SCLK / (2 << CONFIG_SYS_PTV)) 23 24 struct omap_gptimer_regs { 25 unsigned int tidr; /* offset 0x00 */ 26 unsigned char res1[12]; 27 unsigned int tiocp_cfg; /* offset 0x10 */ 28 unsigned char res2[12]; 29 unsigned int tier; /* offset 0x20 */ 30 unsigned int tistatr; /* offset 0x24 */ 31 unsigned int tistat; /* offset 0x28 */ 32 unsigned int tisr; /* offset 0x2c */ 33 unsigned int tcicr; /* offset 0x30 */ 34 unsigned int twer; /* offset 0x34 */ 35 unsigned int tclr; /* offset 0x38 */ 36 unsigned int tcrr; /* offset 0x3c */ 37 unsigned int tldr; /* offset 0x40 */ 38 unsigned int ttgr; /* offset 0x44 */ 39 unsigned int twpc; /* offset 0x48 */ 40 unsigned int tmar; /* offset 0x4c */ 41 unsigned int tcar1; /* offset 0x50 */ 42 unsigned int tscir; /* offset 0x54 */ 43 unsigned int tcar2; /* offset 0x58 */ 44 }; 45 46 /* Omap Timer Priv */ 47 struct omap_timer_priv { 48 struct omap_gptimer_regs *regs; 49 }; 50 51 static int omap_timer_get_count(struct udevice *dev, u64 *count) 52 { 53 struct omap_timer_priv *priv = dev_get_priv(dev); 54 55 *count = readl(&priv->regs->tcrr); 56 57 return 0; 58 } 59 60 static int omap_timer_probe(struct udevice *dev) 61 { 62 struct timer_dev_priv *uc_priv = dev_get_uclass_priv(dev); 63 struct omap_timer_priv *priv = dev_get_priv(dev); 64 65 uc_priv->clock_rate = TIMER_CLOCK; 66 67 /* start the counter ticking up, reload value on overflow */ 68 writel(0, &priv->regs->tldr); 69 /* enable timer */ 70 writel((CONFIG_SYS_PTV << 2) | TCLR_PRE_EN | TCLR_AUTO_RELOAD | 71 TCLR_START, &priv->regs->tclr); 72 73 return 0; 74 } 75 76 static int omap_timer_ofdata_to_platdata(struct udevice *dev) 77 { 78 struct omap_timer_priv *priv = dev_get_priv(dev); 79 80 priv->regs = map_physmem(devfdt_get_addr(dev), 81 sizeof(struct omap_gptimer_regs), MAP_NOCACHE); 82 83 return 0; 84 } 85 86 87 static const struct timer_ops omap_timer_ops = { 88 .get_count = omap_timer_get_count, 89 }; 90 91 static const struct udevice_id omap_timer_ids[] = { 92 { .compatible = "ti,am335x-timer" }, 93 { .compatible = "ti,am4372-timer" }, 94 { .compatible = "ti,omap5430-timer" }, 95 {} 96 }; 97 98 U_BOOT_DRIVER(omap_timer) = { 99 .name = "omap_timer", 100 .id = UCLASS_TIMER, 101 .of_match = omap_timer_ids, 102 .ofdata_to_platdata = omap_timer_ofdata_to_platdata, 103 .priv_auto_alloc_size = sizeof(struct omap_timer_priv), 104 .probe = omap_timer_probe, 105 .ops = &omap_timer_ops, 106 .flags = DM_FLAG_PRE_RELOC, 107 }; 108