xref: /aosp_15_r20/external/arm-trusted-firmware/plat/layerscape/common/ls_timer.c (revision 54fd6939e177f8ff529b10183254802c76df6d08)
1*54fd6939SJiyong Park /*
2*54fd6939SJiyong Park  * Copyright (c) 2018, ARM Limited and Contributors. All rights reserved.
3*54fd6939SJiyong Park  *
4*54fd6939SJiyong Park  * SPDX-License-Identifier: BSD-3-Clause
5*54fd6939SJiyong Park  */
6*54fd6939SJiyong Park 
7*54fd6939SJiyong Park #include <arch_helpers.h>
8*54fd6939SJiyong Park #include <drivers/delay_timer.h>
9*54fd6939SJiyong Park #include <lib/mmio.h>
10*54fd6939SJiyong Park 
11*54fd6939SJiyong Park #define TIMER_BASE_ADDR 0x02B00000
12*54fd6939SJiyong Park 
ls_get_timer(uint64_t start)13*54fd6939SJiyong Park uint64_t ls_get_timer(uint64_t start)
14*54fd6939SJiyong Park {
15*54fd6939SJiyong Park 	return read_cntpct_el0() * 1000 / read_cntfrq_el0() - start;
16*54fd6939SJiyong Park }
17*54fd6939SJiyong Park 
ls_timeus_get_value(void)18*54fd6939SJiyong Park static uint32_t ls_timeus_get_value(void)
19*54fd6939SJiyong Park {
20*54fd6939SJiyong Park 	/*
21*54fd6939SJiyong Park 	 * Generic delay timer implementation expects the timer to be a down
22*54fd6939SJiyong Park 	 * counter. We apply bitwise NOT operator to the tick values returned
23*54fd6939SJiyong Park 	 * by read_cntpct_el0() to simulate the down counter. The value is
24*54fd6939SJiyong Park 	 * clipped from 64 to 32 bits.
25*54fd6939SJiyong Park 	 */
26*54fd6939SJiyong Park 	return (uint32_t)(~read_cntpct_el0());
27*54fd6939SJiyong Park }
28*54fd6939SJiyong Park 
29*54fd6939SJiyong Park static const timer_ops_t ls_timer_ops = {
30*54fd6939SJiyong Park 	.get_timer_value	= ls_timeus_get_value,
31*54fd6939SJiyong Park 	.clk_mult		= 1,
32*54fd6939SJiyong Park 	.clk_div		= 25,
33*54fd6939SJiyong Park };
34*54fd6939SJiyong Park 
35*54fd6939SJiyong Park 
36*54fd6939SJiyong Park /*
37*54fd6939SJiyong Park  * Initialise the nxp layerscape on-chip free rolling us counter as the delay
38*54fd6939SJiyong Park  * timer.
39*54fd6939SJiyong Park  */
ls_delay_timer_init(void)40*54fd6939SJiyong Park void ls_delay_timer_init(void)
41*54fd6939SJiyong Park {
42*54fd6939SJiyong Park 	uintptr_t cntcr =  TIMER_BASE_ADDR;
43*54fd6939SJiyong Park 
44*54fd6939SJiyong Park 	mmio_write_32(cntcr, 0x1);
45*54fd6939SJiyong Park 
46*54fd6939SJiyong Park 	timer_init(&ls_timer_ops);
47*54fd6939SJiyong Park }
48