3 * Vipin Kumar, ST Micoelectronics, vipin.kumar@st.com.
5 * SPDX-License-Identifier: GPL-2.0+
10 #include <asm/arch/hardware.h>
11 #include <asm/arch/spr_gpt.h>
12 #include <asm/arch/spr_misc.h>
14 #define GPT_RESOLUTION (CONFIG_SPEAR_HZ_CLOCK / CONFIG_SPEAR_HZ)
15 #define READ_TIMER() (readl(&gpt_regs_p->count) & GPT_FREE_RUNNING)
17 static struct gpt_regs *const gpt_regs_p =
18 (struct gpt_regs *)CONFIG_SPEAR_TIMERBASE;
20 static struct misc_regs *const misc_regs_p =
21 (struct misc_regs *)CONFIG_SPEAR_MISCBASE;
23 DECLARE_GLOBAL_DATA_PTR;
25 #define timestamp gd->arch.tbl
26 #define lastdec gd->arch.lastinc
32 /* Prescaler setting */
33 #if defined(CONFIG_SPEAR3XX)
34 writel(MISC_PRSC_CFG, &misc_regs_p->prsc2_clk_cfg);
35 synth = MISC_GPT4SYNTH;
36 #elif defined(CONFIG_SPEAR600)
37 writel(MISC_PRSC_CFG, &misc_regs_p->prsc1_clk_cfg);
38 synth = MISC_GPT3SYNTH;
40 # error Incorrect config. Can only be spear{600|300|310|320}
43 writel(readl(&misc_regs_p->periph_clk_cfg) | synth,
44 &misc_regs_p->periph_clk_cfg);
47 writel(GPT_PRESCALER_1 | GPT_MODE_AUTO_RELOAD, &gpt_regs_p->control);
49 /* load value for free running */
50 writel(GPT_FREE_RUNNING, &gpt_regs_p->compare);
52 /* auto reload, start timer */
53 writel(readl(&gpt_regs_p->control) | GPT_ENABLE, &gpt_regs_p->control);
56 lastdec = READ_TIMER();
63 * timer without interrupts
65 ulong get_timer(ulong base)
67 return (get_timer_masked() / GPT_RESOLUTION) - base;
70 void __udelay(unsigned long usec)
73 ulong start = get_timer_masked();
74 ulong tenudelcnt = CONFIG_SPEAR_HZ_CLOCK / (1000 * 100);
77 rndoff = (usec % 10) ? 1 : 0;
79 /* tenudelcnt timer tick gives 10 microsecconds delay */
80 tmo = ((usec / 10) + rndoff) * tenudelcnt;
82 while ((ulong) (get_timer_masked() - start) < tmo)
86 ulong get_timer_masked(void)
88 ulong now = READ_TIMER();
92 timestamp += now - lastdec;
94 /* we have an overflow ... */
95 timestamp += now + GPT_FREE_RUNNING - lastdec;
102 void udelay_masked(unsigned long usec)
108 * This function is derived from PowerPC code (read timebase as long long).
109 * On ARM it just returns the timer value.
111 unsigned long long get_ticks(void)
117 * This function is derived from PowerPC code (timebase clock frequency).
118 * On ARM it returns the number of timer ticks per second.
120 ulong get_tbclk(void)
122 return CONFIG_SPEAR_HZ;