1 // SPDX-License-Identifier: GPL-2.0+
4 * Sascha Hauer, Pengutronix
6 * (C) Copyright 2009 Freescale Semiconductor, Inc.
14 #include <asm/arch/imx-regs.h>
15 #include <asm/arch/clock.h>
16 #include <asm/arch/sys_proto.h>
18 /* General purpose timers registers */
21 unsigned int prescaler;
23 unsigned int nouse[6];
27 static struct mxc_gpt *cur_gpt = (struct mxc_gpt *)GPT1_BASE_ADDR;
29 /* General purpose timers bitfields */
30 #define GPTCR_SWR (1 << 15) /* Software reset */
31 #define GPTCR_24MEN (1 << 10) /* Enable 24MHz clock input */
32 #define GPTCR_FRR (1 << 9) /* Freerun / restart */
33 #define GPTCR_CLKSOURCE_32 (4 << 6) /* Clock source 32khz */
34 #define GPTCR_CLKSOURCE_OSC (5 << 6) /* Clock source OSC */
35 #define GPTCR_CLKSOURCE_PRE (1 << 6) /* Clock source PRECLK */
36 #define GPTCR_CLKSOURCE_MASK (0x7 << 6)
37 #define GPTCR_TEN 1 /* Timer enable */
39 #define GPTPR_PRESCALER24M_SHIFT 12
40 #define GPTPR_PRESCALER24M_MASK (0xF << GPTPR_PRESCALER24M_SHIFT)
42 static inline int gpt_has_clk_source_osc(void)
44 #if defined(CONFIG_MX6)
45 if (((is_mx6dq()) && (soc_rev() > CHIP_REV_1_0)) ||
46 is_mx6dqp() || is_mx6sdl() || is_mx6sx() || is_mx6ul() ||
47 is_mx6ull() || is_mx6sll())
56 static inline ulong gpt_get_clk(void)
58 #ifdef CONFIG_MXC_GPT_HCLK
59 if (gpt_has_clk_source_osc())
62 return mxc_get_clock(MXC_IPG_PERCLK);
72 /* setup GP Timer 1 */
73 __raw_writel(GPTCR_SWR, &cur_gpt->control);
75 /* We have no udelay by now */
76 __raw_writel(0, &cur_gpt->control);
78 i = __raw_readl(&cur_gpt->control);
79 i &= ~GPTCR_CLKSOURCE_MASK;
81 #ifdef CONFIG_MXC_GPT_HCLK
82 if (gpt_has_clk_source_osc()) {
83 i |= GPTCR_CLKSOURCE_OSC | GPTCR_TEN;
86 * For DL/S, SX, UL, ULL, SLL set 24Mhz OSC
87 * Enable bit and prescaler
89 if (is_mx6sdl() || is_mx6sx() || is_mx6ul() || is_mx6ull() ||
93 /* Produce 3Mhz clock */
94 __raw_writel((7 << GPTPR_PRESCALER24M_SHIFT),
98 i |= GPTCR_CLKSOURCE_PRE | GPTCR_TEN;
101 __raw_writel(0, &cur_gpt->prescaler); /* 32Khz */
102 i |= GPTCR_CLKSOURCE_32 | GPTCR_TEN;
104 __raw_writel(i, &cur_gpt->control);
109 unsigned long timer_read_counter(void)
111 return __raw_readl(&cur_gpt->counter); /* current tick value */
115 * This function is derived from PowerPC code (timebase clock frequency).
116 * On ARM it returns the number of timer ticks per second.
118 ulong get_tbclk(void)
120 return gpt_get_clk();
124 * This function is intended for SHORT delays only.
125 * It will overflow at around 10 seconds @ 400MHz,
126 * or 20 seconds @ 200MHz.
128 unsigned long usec2ticks(unsigned long _usec)
130 unsigned long long usec = _usec;
134 do_div(usec, 1000000);