1 files changed, 170 insertions, 0 deletions
diff --git a/arch/x86/cpu/braswell/cpu.c b/arch/x86/cpu/braswell/cpu.c
new file mode 100644
index 0000000000..6ff9036597
--- /dev/null
+++ b/arch/x86/cpu/braswell/cpu.c
@@ -0,0 +1,170 @@
+/*
+ * Copyright (C) 2017, Bin Meng <bmeng.cn@gmail.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ *
+ * Derived from arch/x86/cpu/baytrail/cpu.c
+ */
+
+#include <common.h>
+#include <cpu.h>
+#include <dm.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>
+
+static const unsigned int braswell_bus_freq_table[] = {
+	83333333,
+	100000000,
+	133333333,
+	116666666,
+	80000000,
+	93333333,
+	90000000,
+	88900000,
+	87500000
+};
+
+static unsigned int braswell_bus_freq(void)
+{
+	msr_t clk_info = msr_read(MSR_BSEL_CR_OVERCLOCK_CONTROL);
+
+	if ((clk_info.lo & 0xf) < (ARRAY_SIZE(braswell_bus_freq_table)))
+		return braswell_bus_freq_table[clk_info.lo & 0xf];
+
+	return 0;
+}
+
+static unsigned long braswell_tsc_freq(void)
+{
+	msr_t platform_info;
+	ulong bclk = braswell_bus_freq();
+
+	if (!bclk)
+		return 0;
+
+	platform_info = msr_read(MSR_PLATFORM_INFO);
+
+	return bclk * ((platform_info.lo >> 8) & 0xff);
+}
+
+static int braswell_get_info(struct udevice *dev, struct cpu_info *info)
+{
+	info->cpu_freq = braswell_tsc_freq();
+	info->features = (1 << CPU_FEAT_L1_CACHE) | (1 << CPU_FEAT_MMU);
+
+	return 0;
+}
+
+static int braswell_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);
+
+		/*
+		 * Braswell 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 void braswell_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);
+
+	/* Enable Burst Mode */
+	msr = msr_read(MSR_IA32_MISC_ENABLES);
+	msr.hi = 0;
+	msr_write(MSR_IA32_MISC_ENABLES, msr);
+
+	/*
+	 * Set guaranteed ratio [21:16] from IACORE_TURBO_RATIOS to
+	 * bits [15:8] of the PERF_CTL
+	 */
+	msr = msr_read(MSR_IACORE_TURBO_RATIOS);
+	perf_ctl.lo = (msr.lo & 0x3f0000) >> 8;
+
+	/*
+	 * Set guaranteed vid [22:16] from IACORE_TURBO_VIDS to
+	 * bits [7:0] of the PERF_CTL
+	 */
+	msr = msr_read(MSR_IACORE_TURBO_VIDS);
+	perf_ctl.lo |= (msr.lo & 0x7f0000) >> 16;
+
+	perf_ctl.hi = 0;
+	msr_write(MSR_IA32_PERF_CTL, perf_ctl);
+}
+
+static int braswell_probe(struct udevice *dev)
+{
+	debug("Init Braswell core\n");
+
+	/*
+	 * On Braswell 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, clear SINGLE_PCTL bit 11 */
+	msr_clrsetbits_64(MSR_PMG_CST_CONFIG_CONTROL, 0x3f080f, 0xe0008),
+	msr_clrsetbits_64(MSR_POWER_MISC,
+			  ENABLE_ULFM_AUTOCM_MASK | ENABLE_INDP_AUTOCM_MASK, 0);
+
+	/* Disable C1E */
+	msr_clrsetbits_64(MSR_POWER_CTL, 2, 0);
+	msr_setbits_64(MSR_POWER_MISC, 0x44);
+
+	/* Set this core to max frequency ratio */
+	braswell_set_max_freq();
+
+	return 0;
+}
+
+static const struct udevice_id braswell_ids[] = {
+	{ .compatible = "intel,braswell-cpu" },
+	{ }
+};
+
+static const struct cpu_ops braswell_ops = {
+	.get_desc	= cpu_x86_get_desc,
+	.get_info	= braswell_get_info,
+	.get_count	= braswell_get_count,
+	.get_vendor	= cpu_x86_get_vendor,
+};
+
+U_BOOT_DRIVER(cpu_x86_braswell_drv) = {
+	.name		= "cpu_x86_braswell",
+	.id		= UCLASS_CPU,
+	.of_match	= braswell_ids,
+	.bind		= cpu_x86_bind,
+	.probe		= braswell_probe,
+	.ops		= &braswell_ops,
+};