From: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Date: Tue, 27 Jul 2021 09:22:40 -0700
Subject: ACPI: DPTF: Add new PCH FIVR methods
Patch-mainline: v5.15-rc1
Git-commit: 7a6226db072beeb63d4c3aaa844b0676ef7a027f
References: jsc#SLE-19223
Some additional information is required for updating PCH FIVR values
upon WiFi channel changes.
New attributes added to the existing sysfs:
fivr_switching_freq_mhz : Get the FIVR switching control frequency.
Uses ACPI method GFCS.
fivr_switching_fault_status: Read the FIVR switching frequency control
fault status. Uses ACPI method GFFS.
ssc_clock_info : Presents SSC (spread spectrum clock) information for
EMI (Electro magnetic interference) control. Use ACPI
method GEMI (refer to the description of GEMI method
below).
GFFS
This ACPI method is used to read the FIVR switching frequency control
fault status.
Bits Description
[0:0] Fault status when set to 1
[31:1] Reserved
GFCS
This ACPI method is used to read the FIVR switching control frequency.
Bits Description
[11:0] Actual Frequency = value * XTAL_FREQ / 128
[31:12] Reserved
GEMI
This ACPI method is used to read the programmed register value for
EMI (Electro magnetic interference) control.
Bits Description
[7:0] Sets clock spectrum spread percentage:
0x00=0.2% , 0x3F=10%
1 LSB = 0.1% increase in spread (for
settings 0x01 thru 0x1C)
1 LSB = 0.2% increase in spread (for
settings 0x1E thru 0x3F)
[8] When set to 1, enables spread
spectrum clock
[9] 0: Triangle mode. FFC frequency
walks around the Fcenter in a linear
fashion
1: Random walk mode. FFC frequency
changes randomly within the SSC
(Spread spectrum clock) range
[10] 0: No white noise. 1: Add white noise
to spread waveform
[11] When 1, future writes are ignored.
Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Lee, Chun-Yi <jlee@suse.com>
---
Documentation/ABI/testing/sysfs-platform-dptf | 40 ++++++++++++++++++++++++++
drivers/acpi/dptf/dptf_pch_fivr.c | 9 +++++
2 files changed, 49 insertions(+)
--- a/Documentation/ABI/testing/sysfs-platform-dptf
+++ b/Documentation/ABI/testing/sysfs-platform-dptf
@@ -111,3 +111,43 @@ Contact: linux-acpi@vger.kernel.org
Description:
(RW) The PCH FIVR (Fully Integrated Voltage Regulator) switching frequency in MHz,
when FIVR clock is 38.4MHz.
+
+What: /sys/bus/platform/devices/INTC1045:00/pch_fivr_switch_frequency/fivr_switching_freq_mhz
+Date: September, 2021
+KernelVersion: v5.15
+Contact: linux-acpi@vger.kernel.org
+Description:
+ (RO) Get the FIVR switching control frequency in MHz.
+
+What: /sys/bus/platform/devices/INTC1045:00/pch_fivr_switch_frequency/fivr_switching_fault_status
+Date: September, 2021
+KernelVersion: v5.15
+Contact: linux-acpi@vger.kernel.org
+Description:
+ (RO) Read the FIVR switching frequency control fault status.
+
+What: /sys/bus/platform/devices/INTC1045:00/pch_fivr_switch_frequency/ssc_clock_info
+Date: September, 2021
+KernelVersion: v5.15
+Contact: linux-acpi@vger.kernel.org
+Description:
+ (RO) Presents SSC (spread spectrum clock) information for EMI
+ (Electro magnetic interference) control. This is a bit mask.
+ Bits Description
+ [7:0] Sets clock spectrum spread percentage:
+ 0x00=0.2% , 0x3F=10%
+ 1 LSB = 0.1% increase in spread (for
+ settings 0x01 thru 0x1C)
+ 1 LSB = 0.2% increase in spread (for
+ settings 0x1E thru 0x3F)
+ [8] When set to 1, enables spread
+ spectrum clock
+ [9] 0: Triangle mode. FFC frequency
+ walks around the Fcenter in a linear
+ fashion
+ 1: Random walk mode. FFC frequency
+ changes randomly within the SSC
+ (Spread spectrum clock) range
+ [10] 0: No white noise. 1: Add white noise
+ to spread waveform
+ [11] When 1, future writes are ignored.
--- a/drivers/acpi/dptf/dptf_pch_fivr.c
+++ b/drivers/acpi/dptf/dptf_pch_fivr.c
@@ -90,15 +90,24 @@ static ssize_t name##_store(struct devic
PCH_FIVR_SHOW(freq_mhz_low_clock, GFC0)
PCH_FIVR_SHOW(freq_mhz_high_clock, GFC1)
+PCH_FIVR_SHOW(ssc_clock_info, GEMI)
+PCH_FIVR_SHOW(fivr_switching_freq_mhz, GFCS)
+PCH_FIVR_SHOW(fivr_switching_fault_status, GFFS)
PCH_FIVR_STORE(freq_mhz_low_clock, RFC0)
PCH_FIVR_STORE(freq_mhz_high_clock, RFC1)
static DEVICE_ATTR_RW(freq_mhz_low_clock);
static DEVICE_ATTR_RW(freq_mhz_high_clock);
+static DEVICE_ATTR_RO(ssc_clock_info);
+static DEVICE_ATTR_RO(fivr_switching_freq_mhz);
+static DEVICE_ATTR_RO(fivr_switching_fault_status);
static struct attribute *fivr_attrs[] = {
&dev_attr_freq_mhz_low_clock.attr,
&dev_attr_freq_mhz_high_clock.attr,
+ &dev_attr_ssc_clock_info.attr,
+ &dev_attr_fivr_switching_freq_mhz.attr,
+ &dev_attr_fivr_switching_fault_status.attr,
NULL
};