From 0108c8b742bd7a3a7c2db8357677211e7eb14fac Mon Sep 17 00:00:00 2001
From: Andrey Petrov <anpetrov@fb.com>
Date: Wed, 23 Oct 2019 17:12:10 -0700
Subject: soc/intel/broadwell_de: Implement smbios_cpu_get_maximum_freq_mhz()

Determine maximum speed by looking at either turbo flex limit or
uncore ratio limit.

Signed-off-by: Andrey Petrov <anpetrov@fb.com>
Change-Id: I0f3a64a40cb1d28d8eb9380c2071ec748e345b88
Reviewed-on: https://review.coreboot.org/c/coreboot/+/36284
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: David Hendricks <david.hendricks@gmail.com>
---
 src/soc/intel/fsp_broadwell_de/cpu.c | 22 ++++++++++++++++++++++
 1 file changed, 22 insertions(+)

(limited to 'src/soc/intel/fsp_broadwell_de/cpu.c')

diff --git a/src/soc/intel/fsp_broadwell_de/cpu.c b/src/soc/intel/fsp_broadwell_de/cpu.c
index ac4dcc92dd..b94ee78d7a 100644
--- a/src/soc/intel/fsp_broadwell_de/cpu.c
+++ b/src/soc/intel/fsp_broadwell_de/cpu.c
@@ -20,6 +20,7 @@
 #include <cpu/cpu.h>
 #include <cpu/intel/microcode.h>
 #include <cpu/intel/smm_reloc.h>
+#include <cpu/intel/turbo.h>
 #include <cpu/x86/cache.h>
 #include <cpu/x86/lapic.h>
 #include <cpu/x86/mp.h>
@@ -27,6 +28,8 @@
 #include <cpu/x86/mtrr.h>
 #include <device/device.h>
 #include <device/pci_ops.h>
+#include <smbios.h>
+#include <soc/broadwell_de.h>
 #include <soc/lpc.h>
 #include <soc/msr.h>
 #include <soc/pattrs.h>
@@ -98,6 +101,25 @@ static void set_max_ratio(void)
 	wrmsr(IA32_PERF_CTL, perf_ctl);
 }
 
+unsigned int smbios_cpu_get_max_speed_mhz(void)
+{
+	msr_t msr;
+	uint32_t uncore_max_ratio, turbo_max_ratio = 0;
+
+	/*
+	 * Use turbo's max ratio if it is enabled, otherwise use
+	 * uncore's max ratio.
+	 */
+	msr = rdmsr(MSR_UNCORE_RATIO_LIMIT);
+	uncore_max_ratio = msr.lo & 0x7f;
+	if (get_turbo_state() == TURBO_ENABLED) {
+		msr = rdmsr(MSR_TURBO_RATIO_LIMIT);
+		turbo_max_ratio = msr.lo & 0xff; /* 1 core */
+	}
+
+	return MAX(uncore_max_ratio, turbo_max_ratio) * CPU_BCLK;
+}
+
 static void alt_smm_lock(void)
 {
 	struct device *dev = pcidev_on_root(LPC_DEV, LPC_FUNC);
-- 
cgit v1.2.3