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1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright (C) 2019 Intel Corporation <www.intel.com>
4  */
5 
6 #include <common.h>
7 #include <cpu_func.h>
8 #include <asm/arch/slimbootloader.h>
9 
10 DECLARE_GLOBAL_DATA_PTR;
11 
12 /**
13  * This sets tsc_base and clock_rate for early_timer and tsc_timer.
14  * The performance info guid hob has all performance timestamp data, but
15  * the only tsc frequency info is used for the timer driver for now.
16  *
17  * Slim Bootloader already calibrated TSC and provides it to U-Boot.
18  * Therefore, U-Boot does not have to re-calibrate TSC.
19  * Configuring tsc_base and clock_rate here makes x86 tsc_timer driver
20  * bypass TSC calibration and use the provided TSC frequency.
21  */
tsc_init(void)22 static void tsc_init(void)
23 {
24 	struct sbl_performance_info *data;
25 	const efi_guid_t guid = SBL_PERFORMANCE_INFO_GUID;
26 
27 	if (!gd->arch.hob_list)
28 		panic("hob list not found!");
29 
30 	gd->arch.tsc_base = rdtsc();
31 	debug("tsc_base=0x%llx\n", gd->arch.tsc_base);
32 
33 	data = hob_get_guid_hob_data(gd->arch.hob_list, NULL, &guid);
34 	if (!data) {
35 		debug("performance info hob not found\n");
36 		return;
37 	}
38 
39 	/* frequency is in KHz, so to Hz */
40 	gd->arch.clock_rate = data->frequency * 1000;
41 	debug("freq=0x%lx\n", gd->arch.clock_rate);
42 }
43 
arch_cpu_init(void)44 int arch_cpu_init(void)
45 {
46 	tsc_init();
47 
48 	return x86_cpu_init_f();
49 }
50 
checkcpu(void)51 int checkcpu(void)
52 {
53 	return 0;
54 }
55 
print_cpuinfo(void)56 int print_cpuinfo(void)
57 {
58 	return default_print_cpuinfo();
59 }
60