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