1 // SPDX-License-Identifier: GPL-2.0+ 2 /* 3 * TI OMAP timer driver 4 * 5 * Copyright (C) 2015, Texas Instruments, Incorporated 6 */ 7 8 #include <common.h> 9 #include <dm.h> 10 #include <errno.h> 11 #include <timer.h> 12 #include <asm/io.h> 13 #include <asm/arch/clock.h> 14 15 /* Timer register bits */ 16 #define TCLR_START BIT(0) /* Start=1 */ 17 #define TCLR_AUTO_RELOAD BIT(1) /* Auto reload */ 18 #define TCLR_PRE_EN BIT(5) /* Pre-scaler enable */ 19 #define TCLR_PTV_SHIFT (2) /* Pre-scaler shift value */ 20 21 #define TIMER_CLOCK (V_SCLK / (2 << CONFIG_SYS_PTV)) 22 23 struct omap_gptimer_regs { 24 unsigned int tidr; /* offset 0x00 */ 25 unsigned char res1[12]; 26 unsigned int tiocp_cfg; /* offset 0x10 */ 27 unsigned char res2[12]; 28 unsigned int tier; /* offset 0x20 */ 29 unsigned int tistatr; /* offset 0x24 */ 30 unsigned int tistat; /* offset 0x28 */ 31 unsigned int tisr; /* offset 0x2c */ 32 unsigned int tcicr; /* offset 0x30 */ 33 unsigned int twer; /* offset 0x34 */ 34 unsigned int tclr; /* offset 0x38 */ 35 unsigned int tcrr; /* offset 0x3c */ 36 unsigned int tldr; /* offset 0x40 */ 37 unsigned int ttgr; /* offset 0x44 */ 38 unsigned int twpc; /* offset 0x48 */ 39 unsigned int tmar; /* offset 0x4c */ 40 unsigned int tcar1; /* offset 0x50 */ 41 unsigned int tscir; /* offset 0x54 */ 42 unsigned int tcar2; /* offset 0x58 */ 43 }; 44 45 /* Omap Timer Priv */ 46 struct omap_timer_priv { 47 struct omap_gptimer_regs *regs; 48 }; 49 50 static int omap_timer_get_count(struct udevice *dev, u64 *count) 51 { 52 struct omap_timer_priv *priv = dev_get_priv(dev); 53 54 *count = timer_conv_64(readl(&priv->regs->tcrr)); 55 56 return 0; 57 } 58 59 static int omap_timer_probe(struct udevice *dev) 60 { 61 struct timer_dev_priv *uc_priv = dev_get_uclass_priv(dev); 62 struct omap_timer_priv *priv = dev_get_priv(dev); 63 64 if (!uc_priv->clock_rate) 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 writel(0, &priv->regs->tcrr); 70 /* enable timer */ 71 writel((CONFIG_SYS_PTV << 2) | TCLR_PRE_EN | TCLR_AUTO_RELOAD | 72 TCLR_START, &priv->regs->tclr); 73 74 return 0; 75 } 76 77 static int omap_timer_ofdata_to_platdata(struct udevice *dev) 78 { 79 struct omap_timer_priv *priv = dev_get_priv(dev); 80 81 priv->regs = map_physmem(devfdt_get_addr(dev), 82 sizeof(struct omap_gptimer_regs), MAP_NOCACHE); 83 84 return 0; 85 } 86 87 88 static const struct timer_ops omap_timer_ops = { 89 .get_count = omap_timer_get_count, 90 }; 91 92 static const struct udevice_id omap_timer_ids[] = { 93 { .compatible = "ti,am335x-timer" }, 94 { .compatible = "ti,am4372-timer" }, 95 { .compatible = "ti,omap5430-timer" }, 96 {} 97 }; 98 99 U_BOOT_DRIVER(omap_timer) = { 100 .name = "omap_timer", 101 .id = UCLASS_TIMER, 102 .of_match = omap_timer_ids, 103 .ofdata_to_platdata = omap_timer_ofdata_to_platdata, 104 .priv_auto_alloc_size = sizeof(struct omap_timer_priv), 105 .probe = omap_timer_probe, 106 .ops = &omap_timer_ops, 107 }; 108