1 /* 2 * (C) Copyright 2000-2002 3 * Wolfgang Denk, DENX Software Engineering, wd@denx.de. 4 * 5 * (C) Copyright 2004, Psyent Corporation <www.psyent.com> 6 * Scott McNutt <smcnutt@psyent.com> 7 * 8 * SPDX-License-Identifier: GPL-2.0+ 9 */ 10 11 #include <common.h> 12 #include <dm.h> 13 #include <errno.h> 14 #include <timer.h> 15 #include <asm/io.h> 16 17 DECLARE_GLOBAL_DATA_PTR; 18 19 /* control register */ 20 #define ALTERA_TIMER_CONT BIT(1) /* Continuous mode */ 21 #define ALTERA_TIMER_START BIT(2) /* Start timer */ 22 #define ALTERA_TIMER_STOP BIT(3) /* Stop timer */ 23 24 struct altera_timer_regs { 25 u32 status; /* Timer status reg */ 26 u32 control; /* Timer control reg */ 27 u32 periodl; /* Timeout period low */ 28 u32 periodh; /* Timeout period high */ 29 u32 snapl; /* Snapshot low */ 30 u32 snaph; /* Snapshot high */ 31 }; 32 33 struct altera_timer_platdata { 34 struct altera_timer_regs *regs; 35 }; 36 37 static int altera_timer_get_count(struct udevice *dev, u64 *count) 38 { 39 struct altera_timer_platdata *plat = dev->platdata; 40 struct altera_timer_regs *const regs = plat->regs; 41 u32 val; 42 43 /* Trigger update */ 44 writel(0x0, ®s->snapl); 45 46 /* Read timer value */ 47 val = readl(®s->snapl) & 0xffff; 48 val |= (readl(®s->snaph) & 0xffff) << 16; 49 *count = timer_conv_64(~val); 50 51 return 0; 52 } 53 54 static int altera_timer_probe(struct udevice *dev) 55 { 56 struct altera_timer_platdata *plat = dev->platdata; 57 struct altera_timer_regs *const regs = plat->regs; 58 59 writel(0, ®s->status); 60 writel(0, ®s->control); 61 writel(ALTERA_TIMER_STOP, ®s->control); 62 63 writel(0xffff, ®s->periodl); 64 writel(0xffff, ®s->periodh); 65 writel(ALTERA_TIMER_CONT | ALTERA_TIMER_START, ®s->control); 66 67 return 0; 68 } 69 70 static int altera_timer_ofdata_to_platdata(struct udevice *dev) 71 { 72 struct altera_timer_platdata *plat = dev_get_platdata(dev); 73 74 plat->regs = map_physmem(dev_get_addr(dev), 75 sizeof(struct altera_timer_regs), 76 MAP_NOCACHE); 77 78 return 0; 79 } 80 81 static const struct timer_ops altera_timer_ops = { 82 .get_count = altera_timer_get_count, 83 }; 84 85 static const struct udevice_id altera_timer_ids[] = { 86 { .compatible = "altr,timer-1.0" }, 87 {} 88 }; 89 90 U_BOOT_DRIVER(altera_timer) = { 91 .name = "altera_timer", 92 .id = UCLASS_TIMER, 93 .of_match = altera_timer_ids, 94 .ofdata_to_platdata = altera_timer_ofdata_to_platdata, 95 .platdata_auto_alloc_size = sizeof(struct altera_timer_platdata), 96 .probe = altera_timer_probe, 97 .ops = &altera_timer_ops, 98 .flags = DM_FLAG_PRE_RELOC, 99 }; 100