1 /* 2 * Copyright (C) 2014, STMicroelectronics - All Rights Reserved 3 * Author(s): Vikas Manocha, <vikas.manocha@st.com> for STMicroelectronics. 4 * 5 * SPDX-License-Identifier: GPL-2.0+ 6 */ 7 8 #include <common.h> 9 #include <asm/io.h> 10 #include <asm/arch-stv0991/hardware.h> 11 #include <asm/arch-stv0991/stv0991_cgu.h> 12 #include <asm/arch-stv0991/stv0991_gpt.h> 13 14 static struct stv0991_cgu_regs *const stv0991_cgu_regs = \ 15 (struct stv0991_cgu_regs *) (CGU_BASE_ADDR); 16 17 #define READ_TIMER() (readl(&gpt1_regs_ptr->cnt) & GPT_FREE_RUNNING) 18 #define GPT_RESOLUTION (CONFIG_STV0991_HZ_CLOCK / CONFIG_STV0991_HZ) 19 20 DECLARE_GLOBAL_DATA_PTR; 21 22 #define timestamp gd->arch.tbl 23 #define lastdec gd->arch.lastinc 24 25 int timer_init(void) 26 { 27 /* Timer1 clock configuration */ 28 writel(TIMER1_CLK_CFG, &stv0991_cgu_regs->tim_freq); 29 writel(readl(&stv0991_cgu_regs->cgu_enable_2) | 30 TIMER1_CLK_EN, &stv0991_cgu_regs->cgu_enable_2); 31 32 /* Stop the timer */ 33 writel(readl(&gpt1_regs_ptr->cr1) & ~GPT_CR1_CEN, &gpt1_regs_ptr->cr1); 34 writel(GPT_PRESCALER_128, &gpt1_regs_ptr->psc); 35 /* Configure timer for auto-reload */ 36 writel(readl(&gpt1_regs_ptr->cr1) | GPT_MODE_AUTO_RELOAD, 37 &gpt1_regs_ptr->cr1); 38 39 /* load value for free running */ 40 writel(GPT_FREE_RUNNING, &gpt1_regs_ptr->arr); 41 42 /* start timer */ 43 writel(readl(&gpt1_regs_ptr->cr1) | GPT_CR1_CEN, 44 &gpt1_regs_ptr->cr1); 45 46 /* Reset the timer */ 47 lastdec = READ_TIMER(); 48 timestamp = 0; 49 50 return 0; 51 } 52 53 /* 54 * timer without interrupts 55 */ 56 ulong get_timer(ulong base) 57 { 58 return (get_timer_masked() / GPT_RESOLUTION) - base; 59 } 60 61 void __udelay(unsigned long usec) 62 { 63 ulong tmo; 64 ulong start = get_timer_masked(); 65 ulong tenudelcnt = CONFIG_STV0991_HZ_CLOCK / (1000 * 100); 66 ulong rndoff; 67 68 rndoff = (usec % 10) ? 1 : 0; 69 70 /* tenudelcnt timer tick gives 10 microsecconds delay */ 71 tmo = ((usec / 10) + rndoff) * tenudelcnt; 72 73 while ((ulong) (get_timer_masked() - start) < tmo) 74 ; 75 } 76 77 ulong get_timer_masked(void) 78 { 79 ulong now = READ_TIMER(); 80 81 if (now >= lastdec) { 82 /* normal mode */ 83 timestamp += now - lastdec; 84 } else { 85 /* we have an overflow ... */ 86 timestamp += now + GPT_FREE_RUNNING - lastdec; 87 } 88 lastdec = now; 89 90 return timestamp; 91 } 92 93 void udelay_masked(unsigned long usec) 94 { 95 return udelay(usec); 96 } 97 98 /* 99 * This function is derived from PowerPC code (read timebase as long long). 100 * On ARM it just returns the timer value. 101 */ 102 unsigned long long get_ticks(void) 103 { 104 return get_timer(0); 105 } 106 107 /* 108 * This function is derived from PowerPC code (timebase clock frequency). 109 * On ARM it returns the number of timer ticks per second. 110 */ 111 ulong get_tbclk(void) 112 { 113 return CONFIG_STV0991_HZ; 114 } 115