1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * Copyright (C) 2015 Google, Inc
4 *
5 * Based on code from coreboot
6 */
7
8 #include <common.h>
9 #include <cpu.h>
10 #include <dm.h>
11 #include <pci.h>
12 #include <asm/cpu.h>
13 #include <asm/cpu_x86.h>
14 #include <asm/io.h>
15 #include <asm/lapic.h>
16 #include <asm/msr.h>
17 #include <asm/turbo.h>
18
19 #define BYT_PRV_CLK 0x800
20 #define BYT_PRV_CLK_EN (1 << 0)
21 #define BYT_PRV_CLK_M_VAL_SHIFT 1
22 #define BYT_PRV_CLK_N_VAL_SHIFT 16
23 #define BYT_PRV_CLK_UPDATE (1 << 31)
24
hsuart_clock_set(void * base)25 static void hsuart_clock_set(void *base)
26 {
27 u32 m, n, reg;
28
29 /*
30 * Configure the BayTrail UART clock for the internal HS UARTs
31 * (PCI devices) to 58982400 Hz
32 */
33 m = 0x2400;
34 n = 0x3d09;
35 reg = (m << BYT_PRV_CLK_M_VAL_SHIFT) | (n << BYT_PRV_CLK_N_VAL_SHIFT);
36 writel(reg, base + BYT_PRV_CLK);
37 reg |= BYT_PRV_CLK_EN | BYT_PRV_CLK_UPDATE;
38 writel(reg, base + BYT_PRV_CLK);
39 }
40
41 /*
42 * Configure the internal clock of both SIO HS-UARTs, if they are enabled
43 * via FSP
44 */
arch_cpu_init_dm(void)45 int arch_cpu_init_dm(void)
46 {
47 struct udevice *dev;
48 void *base;
49 int ret;
50 int i;
51
52 /* Loop over the 2 HS-UARTs */
53 for (i = 0; i < 2; i++) {
54 ret = dm_pci_bus_find_bdf(PCI_BDF(0, 0x1e, 3 + i), &dev);
55 if (!ret) {
56 base = dm_pci_map_bar(dev, PCI_BASE_ADDRESS_0,
57 PCI_REGION_MEM);
58 hsuart_clock_set(base);
59 }
60 }
61
62 return 0;
63 }
64
set_max_freq(void)65 static void set_max_freq(void)
66 {
67 msr_t perf_ctl;
68 msr_t msr;
69
70 /* Enable speed step */
71 msr = msr_read(MSR_IA32_MISC_ENABLES);
72 msr.lo |= (1 << 16);
73 msr_write(MSR_IA32_MISC_ENABLES, msr);
74
75 /*
76 * Set guaranteed ratio [21:16] from IACORE_RATIOS to bits [15:8] of
77 * the PERF_CTL
78 */
79 msr = msr_read(MSR_IACORE_RATIOS);
80 perf_ctl.lo = (msr.lo & 0x3f0000) >> 8;
81
82 /*
83 * Set guaranteed vid [22:16] from IACORE_VIDS to bits [7:0] of
84 * the PERF_CTL
85 */
86 msr = msr_read(MSR_IACORE_VIDS);
87 perf_ctl.lo |= (msr.lo & 0x7f0000) >> 16;
88 perf_ctl.hi = 0;
89
90 msr_write(MSR_IA32_PERF_CTL, perf_ctl);
91 }
92
cpu_x86_baytrail_probe(struct udevice * dev)93 static int cpu_x86_baytrail_probe(struct udevice *dev)
94 {
95 if (!ll_boot_init())
96 return 0;
97 debug("Init BayTrail core\n");
98
99 /*
100 * On BayTrail the turbo disable bit is actually scoped at the
101 * building-block level, not package. For non-BSP cores that are
102 * within a building block, enable turbo. The cores within the BSP's
103 * building block will just see it already enabled and move on.
104 */
105 if (lapicid())
106 turbo_enable();
107
108 /* Dynamic L2 shrink enable and threshold */
109 msr_clrsetbits_64(MSR_PMG_CST_CONFIG_CONTROL, 0x3f000f, 0xe0008),
110
111 /* Disable C1E */
112 msr_clrsetbits_64(MSR_POWER_CTL, 2, 0);
113 msr_setbits_64(MSR_POWER_MISC, 0x44);
114
115 /* Set this core to max frequency ratio */
116 set_max_freq();
117
118 return 0;
119 }
120
bus_freq(void)121 static unsigned bus_freq(void)
122 {
123 msr_t clk_info = msr_read(MSR_BSEL_CR_OVERCLOCK_CONTROL);
124 switch (clk_info.lo & 0x3) {
125 case 0:
126 return 83333333;
127 case 1:
128 return 100000000;
129 case 2:
130 return 133333333;
131 case 3:
132 return 116666666;
133 default:
134 return 0;
135 }
136 }
137
tsc_freq(void)138 static unsigned long tsc_freq(void)
139 {
140 msr_t platform_info;
141 ulong bclk = bus_freq();
142
143 if (!bclk)
144 return 0;
145
146 platform_info = msr_read(MSR_PLATFORM_INFO);
147
148 return bclk * ((platform_info.lo >> 8) & 0xff);
149 }
150
baytrail_get_info(struct udevice * dev,struct cpu_info * info)151 static int baytrail_get_info(struct udevice *dev, struct cpu_info *info)
152 {
153 info->cpu_freq = tsc_freq();
154 info->features = 1 << CPU_FEAT_L1_CACHE | 1 << CPU_FEAT_MMU;
155
156 return 0;
157 }
158
baytrail_get_count(struct udevice * dev)159 static int baytrail_get_count(struct udevice *dev)
160 {
161 int ecx = 0;
162
163 /*
164 * Use the algorithm described in Intel 64 and IA-32 Architectures
165 * Software Developer's Manual Volume 3 (3A, 3B & 3C): System
166 * Programming Guide, Jan-2015. Section 8.9.2: Hierarchical Mapping
167 * of CPUID Extended Topology Leaf.
168 */
169 while (1) {
170 struct cpuid_result leaf_b;
171
172 leaf_b = cpuid_ext(0xb, ecx);
173
174 /*
175 * Bay Trail doesn't have hyperthreading so just determine the
176 * number of cores by from level type (ecx[15:8] == * 2)
177 */
178 if ((leaf_b.ecx & 0xff00) == 0x0200)
179 return leaf_b.ebx & 0xffff;
180
181 ecx++;
182 }
183
184 return 0;
185 }
186
187 static const struct cpu_ops cpu_x86_baytrail_ops = {
188 .get_desc = cpu_x86_get_desc,
189 .get_info = baytrail_get_info,
190 .get_count = baytrail_get_count,
191 .get_vendor = cpu_x86_get_vendor,
192 };
193
194 static const struct udevice_id cpu_x86_baytrail_ids[] = {
195 { .compatible = "intel,baytrail-cpu" },
196 { }
197 };
198
199 U_BOOT_DRIVER(cpu_x86_baytrail_drv) = {
200 .name = "cpu_x86_baytrail",
201 .id = UCLASS_CPU,
202 .of_match = cpu_x86_baytrail_ids,
203 .bind = cpu_x86_bind,
204 .probe = cpu_x86_baytrail_probe,
205 .ops = &cpu_x86_baytrail_ops,
206 .flags = DM_FLAG_PRE_RELOC,
207 };
208