From c0e2c81d8e845cd700bb2311514f9d6877f784bb Mon Sep 17 00:00:00 2001
From: Simon Glass <sjg@chromium.org>
Date: Sun, 20 Oct 2019 21:37:49 -0600
Subject: [PATCH] x86: spl: Support init of a PUNIT

The x86 power unit handles power management. Support initing this device
which is modelled as a new type of system controller since there are no
operations needed.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
---
 arch/x86/include/asm/cpu.h |  1 +
 arch/x86/lib/spl.c         | 40 ++++++++++++++++++++++++++++++++++++++
 2 files changed, 41 insertions(+)

diff --git a/arch/x86/include/asm/cpu.h b/arch/x86/include/asm/cpu.h
index feee0f915f..21a05dab7d 100644
--- a/arch/x86/include/asm/cpu.h
+++ b/arch/x86/include/asm/cpu.h
@@ -55,6 +55,7 @@ enum {
 	X86_SYSCON_PINCONF,	/* Intel x86 pin configuration */
 	X86_SYSCON_PMU,		/* Power Management Unit */
 	X86_SYSCON_SCU,		/* System Controller Unit */
+	X86_SYSCON_PUNIT,	/* Power unit */
 };
 
 struct cpuid_result {
diff --git a/arch/x86/lib/spl.c b/arch/x86/lib/spl.c
index 7623fc9ada..a8eaafeb5b 100644
--- a/arch/x86/lib/spl.c
+++ b/arch/x86/lib/spl.c
@@ -5,11 +5,15 @@
 
 #include <common.h>
 #include <debug_uart.h>
+#include <dm.h>
 #include <malloc.h>
 #include <spl.h>
+#include <syscon.h>
 #include <asm/cpu.h>
+#include <asm/cpu_common.h>
 #include <asm/mrccache.h>
 #include <asm/mtrr.h>
+#include <asm/pci.h>
 #include <asm/processor.h>
 #include <asm/spl.h>
 #include <asm-generic/sections.h>
@@ -21,6 +25,32 @@ __weak int arch_cpu_init_dm(void)
 	return 0;
 }
 
+#ifdef CONFIG_TPL
+
+static int set_max_freq(void)
+{
+	if (cpu_get_burst_mode_state() == BURST_MODE_UNAVAILABLE) {
+		/*
+		 * Burst Mode has been factory-configured as disabled and is not
+		 * available in this physical processor package
+		 */
+		debug("Burst Mode is factory-disabled\n");
+		return -ENOENT;
+	}
+
+	/* Enable burst mode */
+	cpu_set_burst_mode(true);
+
+	/* Enable speed step */
+	cpu_set_eist(true);
+
+	/* Set P-State ratio */
+	cpu_set_p_state_to_turbo_ratio();
+
+	return 0;
+}
+#endif
+
 static int x86_spl_init(void)
 {
 #ifndef CONFIG_TPL
@@ -31,6 +61,8 @@ static int x86_spl_init(void)
 	 * place it immediately below CONFIG_SYS_TEXT_BASE.
 	 */
 	char *ptr = (char *)0x110000;
+#else
+	struct udevice *punit;
 #endif
 	int ret;
 
@@ -101,6 +133,14 @@ static int x86_spl_init(void)
 		return ret;
 	}
 	mtrr_commit(true);
+#else
+	ret = syscon_get_by_driver_data(X86_SYSCON_PUNIT, &punit);
+	if (ret)
+		debug("Could not find PUNIT (err=%d)\n", ret);
+
+	ret = set_max_freq();
+	if (ret)
+		debug("Failed to set CPU frequency (err=%d)\n", ret);
 #endif
 
 	return 0;