xref: /rk3399_ARM-atf/plat/intel/soc/common/socfpga_delay_timer.c (revision 811af8b768e3535899b642e0ee1f375dc8f0d417)
1d8820789SHadi Asyrafi /*
2d8820789SHadi Asyrafi  * Copyright (c) 2019, ARM Limited and Contributors. All rights reserved.
3d8820789SHadi Asyrafi  *
4d8820789SHadi Asyrafi  * SPDX-License-Identifier: BSD-3-Clause
5d8820789SHadi Asyrafi  */
6d8820789SHadi Asyrafi 
7d8820789SHadi Asyrafi #include <assert.h>
8d8820789SHadi Asyrafi #include <arch_helpers.h>
9d8820789SHadi Asyrafi #include <drivers/delay_timer.h>
10d8820789SHadi Asyrafi #include <lib/mmio.h>
11d8820789SHadi Asyrafi 
12d8820789SHadi Asyrafi #define SOCFPGA_GLOBAL_TIMER		0xffd01000
13d8820789SHadi Asyrafi #define SOCFPGA_GLOBAL_TIMER_EN		0x3
14d8820789SHadi Asyrafi 
15d8820789SHadi Asyrafi /********************************************************************
16d8820789SHadi Asyrafi  * The timer delay function
17d8820789SHadi Asyrafi  ********************************************************************/
18d8820789SHadi Asyrafi static uint32_t socfpga_get_timer_value(void)
19d8820789SHadi Asyrafi {
20d8820789SHadi Asyrafi 	/*
21d8820789SHadi Asyrafi 	 * Generic delay timer implementation expects the timer to be a down
22d8820789SHadi Asyrafi 	 * counter. We apply bitwise NOT operator to the tick values returned
23d8820789SHadi Asyrafi 	 * by read_cntpct_el0() to simulate the down counter. The value is
24d8820789SHadi Asyrafi 	 * clipped from 64 to 32 bits.
25d8820789SHadi Asyrafi 	 */
26d8820789SHadi Asyrafi 	return (uint32_t)(~read_cntpct_el0());
27d8820789SHadi Asyrafi }
28d8820789SHadi Asyrafi 
29d8820789SHadi Asyrafi static const timer_ops_t plat_timer_ops = {
30d8820789SHadi Asyrafi 	.get_timer_value    = socfpga_get_timer_value,
31d8820789SHadi Asyrafi 	.clk_mult           = 1,
32d8820789SHadi Asyrafi 	.clk_div	    = PLAT_SYS_COUNTER_FREQ_IN_MHZ,
33d8820789SHadi Asyrafi };
34d8820789SHadi Asyrafi 
35d8820789SHadi Asyrafi void socfpga_delay_timer_init(void)
36d8820789SHadi Asyrafi {
37d8820789SHadi Asyrafi 	timer_init(&plat_timer_ops);
38d8820789SHadi Asyrafi 	mmio_write_32(SOCFPGA_GLOBAL_TIMER, SOCFPGA_GLOBAL_TIMER_EN);
39*811af8b7STien Hock Loh 
40*811af8b7STien Hock Loh 	asm volatile("msr cntp_ctl_el0, %0" : : "r" (SOCFPGA_GLOBAL_TIMER_EN));
41*811af8b7STien Hock Loh 	asm volatile("msr cntp_tval_el0, %0" : : "r" (~0));
42*811af8b7STien Hock Loh 
43d8820789SHadi Asyrafi }
44