summaryrefslogtreecommitdiff
path: root/arch/x86/cpu/baytrail/cpu.c
blob: 0bb08524f8df4a5d668a0b03ea0183da22192087 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
/*
 * Copyright (C) 2015 Google, Inc
 *
 * SPDX-License-Identifier:	GPL-2.0+
 *
 * Based on code from coreboot
 */

#include <common.h>
#include <cpu.h>
#include <dm.h>
#include <pci.h>
#include <asm/cpu.h>
#include <asm/cpu_x86.h>
#include <asm/io.h>
#include <asm/lapic.h>
#include <asm/msr.h>
#include <asm/turbo.h>

#define BYT_PRV_CLK			0x800
#define BYT_PRV_CLK_EN			(1 << 0)
#define BYT_PRV_CLK_M_VAL_SHIFT		1
#define BYT_PRV_CLK_N_VAL_SHIFT		16
#define BYT_PRV_CLK_UPDATE		(1 << 31)

static void hsuart_clock_set(void *base)
{
	u32 m, n, reg;

	/*
	 * Configure the BayTrail UART clock for the internal HS UARTs
	 * (PCI devices) to 58982400 Hz
	 */
	m = 0x2400;
	n = 0x3d09;
	reg = (m << BYT_PRV_CLK_M_VAL_SHIFT) | (n << BYT_PRV_CLK_N_VAL_SHIFT);
	writel(reg, base + BYT_PRV_CLK);
	reg |= BYT_PRV_CLK_EN | BYT_PRV_CLK_UPDATE;
	writel(reg, base + BYT_PRV_CLK);
}

/*
 * Configure the internal clock of both SIO HS-UARTs, if they are enabled
 * via FSP
 */
int arch_cpu_init_dm(void)
{
	struct udevice *dev;
	void *base;
	int ret;
	int i;

	/* Loop over the 2 HS-UARTs */
	for (i = 0; i < 2; i++) {
		ret = dm_pci_bus_find_bdf(PCI_BDF(0, 0x1e, 3 + i), &dev);
		if (!ret) {
			base = dm_pci_map_bar(dev, PCI_BASE_ADDRESS_0,
					      PCI_REGION_MEM);
			hsuart_clock_set(base);
		}
	}

	return 0;
}

static void set_max_freq(void)
{
	msr_t perf_ctl;
	msr_t msr;

	/* Enable speed step */
	msr = msr_read(MSR_IA32_MISC_ENABLES);
	msr.lo |= (1 << 16);
	msr_write(MSR_IA32_MISC_ENABLES, msr);

	/*
	 * Set guaranteed ratio [21:16] from IACORE_RATIOS to bits [15:8] of
	 * the PERF_CTL
	 */
	msr = msr_read(MSR_IACORE_RATIOS);
	perf_ctl.lo = (msr.lo & 0x3f0000) >> 8;

	/*
	 * Set guaranteed vid [21:16] from IACORE_VIDS to bits [7:0] of
	 * the PERF_CTL
	 */
	msr = msr_read(MSR_IACORE_VIDS);
	perf_ctl.lo |= (msr.lo & 0x7f0000) >> 16;
	perf_ctl.hi = 0;

	msr_write(MSR_IA32_PERF_CTL, perf_ctl);
}

static int cpu_x86_baytrail_probe(struct udevice *dev)
{
	if (!ll_boot_init())
		return 0;
	debug("Init BayTrail core\n");

	/*
	 * On BayTrail the turbo disable bit is actually scoped at the
	 * building-block level, not package. For non-BSP cores that are
	 * within a building block, enable turbo. The cores within the BSP's
	 * building block will just see it already enabled and move on.
	 */
	if (lapicid())
		turbo_enable();

	/* Dynamic L2 shrink enable and threshold */
	msr_clrsetbits_64(MSR_PMG_CST_CONFIG_CONTROL, 0x3f000f, 0xe0008),

	/* Disable C1E */
	msr_clrsetbits_64(MSR_POWER_CTL, 2, 0);
	msr_setbits_64(MSR_POWER_MISC, 0x44);

	/* Set this core to max frequency ratio */
	set_max_freq();

	return 0;
}

static unsigned bus_freq(void)
{
	msr_t clk_info = msr_read(MSR_BSEL_CR_OVERCLOCK_CONTROL);
	switch (clk_info.lo & 0x3) {
	case 0:
		return 83333333;
	case 1:
		return 100000000;
	case 2:
		return 133333333;
	case 3:
		return 116666666;
	default:
		return 0;
	}
}

static unsigned long tsc_freq(void)
{
	msr_t platform_info;
	ulong bclk = bus_freq();

	if (!bclk)
		return 0;

	platform_info = msr_read(MSR_PLATFORM_INFO);

	return bclk * ((platform_info.lo >> 8) & 0xff);
}

static int baytrail_get_info(struct udevice *dev, struct cpu_info *info)
{
	info->cpu_freq = tsc_freq();
	info->features = 1 << CPU_FEAT_L1_CACHE | 1 << CPU_FEAT_MMU;

	return 0;
}

static int baytrail_get_count(struct udevice *dev)
{
	int ecx = 0;

	/*
	 * Use the algorithm described in Intel 64 and IA-32 Architectures
	 * Software Developer's Manual Volume 3 (3A, 3B & 3C): System
	 * Programming Guide, Jan-2015. Section 8.9.2: Hierarchical Mapping
	 * of CPUID Extended Topology Leaf.
	 */
	while (1) {
		struct cpuid_result leaf_b;

		leaf_b = cpuid_ext(0xb, ecx);

		/*
		 * Bay Trail doesn't have hyperthreading so just determine the
		 * number of cores by from level type (ecx[15:8] == * 2)
		 */
		if ((leaf_b.ecx & 0xff00) == 0x0200)
			return leaf_b.ebx & 0xffff;

		ecx++;
	}

	return 0;
}

static const struct cpu_ops cpu_x86_baytrail_ops = {
	.get_desc	= cpu_x86_get_desc,
	.get_info	= baytrail_get_info,
	.get_count	= baytrail_get_count,
	.get_vendor	= cpu_x86_get_vendor,
};

static const struct udevice_id cpu_x86_baytrail_ids[] = {
	{ .compatible = "intel,baytrail-cpu" },
	{ }
};

U_BOOT_DRIVER(cpu_x86_baytrail_drv) = {
	.name		= "cpu_x86_baytrail",
	.id		= UCLASS_CPU,
	.of_match	= cpu_x86_baytrail_ids,
	.bind		= cpu_x86_bind,
	.probe		= cpu_x86_baytrail_probe,
	.ops		= &cpu_x86_baytrail_ops,
};