diff options
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/ABI/testing/sysfs-class-devfreq | 54 | ||||
| -rw-r--r-- | Documentation/admin-guide/bootconfig.rst | 20 | ||||
| -rw-r--r-- | Documentation/devicetree/bindings/devfreq/exynos-bus.txt | 71 | ||||
| -rw-r--r-- | Documentation/devicetree/bindings/display/brcm,bcm2711-hdmi.yaml | 6 | ||||
| -rw-r--r-- | Documentation/devicetree/bindings/net/can/tcan4x5x.txt | 2 | ||||
| -rw-r--r-- | Documentation/devicetree/bindings/net/nfc/nxp-nci.txt | 2 | ||||
| -rw-r--r-- | Documentation/devicetree/bindings/net/nfc/pn544.txt | 2 | ||||
| -rw-r--r-- | Documentation/devicetree/bindings/opp/opp.txt | 54 | ||||
| -rw-r--r-- | Documentation/driver-api/media/drivers/vidtv.rst | 120 | ||||
| -rw-r--r-- | Documentation/driver-api/thermal/power_allocator.rst | 12 | ||||
| -rw-r--r-- | Documentation/kbuild/llvm.rst | 5 | ||||
| -rw-r--r-- | Documentation/networking/netdev-FAQ.rst | 26 | ||||
| -rw-r--r-- | Documentation/power/energy-model.rst | 30 | ||||
| -rw-r--r-- | Documentation/scheduler/sched-energy.rst | 5 |
14 files changed, 351 insertions, 58 deletions
diff --git a/Documentation/ABI/testing/sysfs-class-devfreq b/Documentation/ABI/testing/sysfs-class-devfreq index b8ebff4b1c4c..386bc230a33d 100644 --- a/Documentation/ABI/testing/sysfs-class-devfreq +++ b/Documentation/ABI/testing/sysfs-class-devfreq @@ -37,20 +37,6 @@ Description: The /sys/class/devfreq/.../target_freq shows the next governor predicted target frequency of the corresponding devfreq object. -What: /sys/class/devfreq/.../polling_interval -Date: September 2011 -Contact: MyungJoo Ham <myungjoo.ham@samsung.com> -Description: - The /sys/class/devfreq/.../polling_interval shows and sets - the requested polling interval of the corresponding devfreq - object. The values are represented in ms. If the value is - less than 1 jiffy, it is considered to be 0, which means - no polling. This value is meaningless if the governor is - not polling; thus. If the governor is not using - devfreq-provided central polling - (/sys/class/devfreq/.../central_polling is 0), this value - may be useless. - What: /sys/class/devfreq/.../trans_stat Date: October 2012 Contact: MyungJoo Ham <myungjoo.ham@samsung.com> @@ -66,14 +52,6 @@ Description: echo 0 > /sys/class/devfreq/.../trans_stat -What: /sys/class/devfreq/.../userspace/set_freq -Date: September 2011 -Contact: MyungJoo Ham <myungjoo.ham@samsung.com> -Description: - The /sys/class/devfreq/.../userspace/set_freq shows and - sets the requested frequency for the devfreq object if - userspace governor is in effect. - What: /sys/class/devfreq/.../available_frequencies Date: October 2012 Contact: Nishanth Menon <nm@ti.com> @@ -110,6 +88,35 @@ Description: The max_freq overrides min_freq because max_freq may be used to throttle devices to avoid overheating. +What: /sys/class/devfreq/.../polling_interval +Date: September 2011 +Contact: MyungJoo Ham <myungjoo.ham@samsung.com> +Description: + The /sys/class/devfreq/.../polling_interval shows and sets + the requested polling interval of the corresponding devfreq + object. The values are represented in ms. If the value is + less than 1 jiffy, it is considered to be 0, which means + no polling. This value is meaningless if the governor is + not polling; thus. If the governor is not using + devfreq-provided central polling + (/sys/class/devfreq/.../central_polling is 0), this value + may be useless. + + A list of governors that support the node: + - simple_ondmenad + - tegra_actmon + +What: /sys/class/devfreq/.../userspace/set_freq +Date: September 2011 +Contact: MyungJoo Ham <myungjoo.ham@samsung.com> +Description: + The /sys/class/devfreq/.../userspace/set_freq shows and + sets the requested frequency for the devfreq object if + userspace governor is in effect. + + A list of governors that support the node: + - userspace + What: /sys/class/devfreq/.../timer Date: July 2020 Contact: Chanwoo Choi <cw00.choi@samsung.com> @@ -122,3 +129,6 @@ Description: echo deferrable > /sys/class/devfreq/.../timer echo delayed > /sys/class/devfreq/.../timer + + A list of governors that support the node: + - simple_ondemand diff --git a/Documentation/admin-guide/bootconfig.rst b/Documentation/admin-guide/bootconfig.rst index a22024f9175e..9b90efcc3a35 100644 --- a/Documentation/admin-guide/bootconfig.rst +++ b/Documentation/admin-guide/bootconfig.rst @@ -137,15 +137,24 @@ Boot Kernel With a Boot Config ============================== Since the boot configuration file is loaded with initrd, it will be added -to the end of the initrd (initramfs) image file with size, checksum and -12-byte magic word as below. +to the end of the initrd (initramfs) image file with padding, size, +checksum and 12-byte magic word as below. -[initrd][bootconfig][size(u32)][checksum(u32)][#BOOTCONFIG\n] +[initrd][bootconfig][padding][size(le32)][checksum(le32)][#BOOTCONFIG\n] + +The size and checksum fields are unsigned 32bit little endian value. + +When the boot configuration is added to the initrd image, the total +file size is aligned to 4 bytes. To fill the gap, null characters +(``\0``) will be added. Thus the ``size`` is the length of the bootconfig +file + padding bytes. The Linux kernel decodes the last part of the initrd image in memory to get the boot configuration data. Because of this "piggyback" method, there is no need to change or -update the boot loader and the kernel image itself. +update the boot loader and the kernel image itself as long as the boot +loader passes the correct initrd file size. If by any chance, the boot +loader passes a longer size, the kernel feils to find the bootconfig data. To do this operation, Linux kernel provides "bootconfig" command under tools/bootconfig, which allows admin to apply or delete the config file @@ -176,7 +185,8 @@ up to 512 key-value pairs. If keys contains 3 words in average, it can contain 256 key-value pairs. In most cases, the number of config items will be under 100 entries and smaller than 8KB, so it would be enough. If the node number exceeds 1024, parser returns an error even if the file -size is smaller than 32KB. +size is smaller than 32KB. (Note that this maximum size is not including +the padding null characters.) Anyway, since bootconfig command verifies it when appending a boot config to initrd image, user can notice it before boot. diff --git a/Documentation/devicetree/bindings/devfreq/exynos-bus.txt b/Documentation/devicetree/bindings/devfreq/exynos-bus.txt index e71f752cc18f..bcaa2c08ac11 100644 --- a/Documentation/devicetree/bindings/devfreq/exynos-bus.txt +++ b/Documentation/devicetree/bindings/devfreq/exynos-bus.txt @@ -51,6 +51,19 @@ Optional properties only for parent bus device: - exynos,saturation-ratio: the percentage value which is used to calibrate the performance count against total cycle count. +Optional properties for the interconnect functionality (QoS frequency +constraints): +- #interconnect-cells: should be 0. +- interconnects: as documented in ../interconnect.txt, describes a path at the + higher level interconnects used by this interconnect provider. + If this interconnect provider is directly linked to a top level interconnect + provider the property contains only one phandle. The provider extends + the interconnect graph by linking its node to a node registered by provider + pointed to by first phandle in the 'interconnects' property. + +- samsung,data-clock-ratio: ratio of the data throughput in B/s to minimum data + clock frequency in Hz, default value is 8 when this property is missing. + Detailed correlation between sub-blocks and power line according to Exynos SoC: - In case of Exynos3250, there are two power line as following: VDD_MIF |--- DMC @@ -135,7 +148,7 @@ Detailed correlation between sub-blocks and power line according to Exynos SoC: |--- PERIC (Fixed clock rate) |--- FSYS (Fixed clock rate) -Example1: +Example 1: Show the AXI buses of Exynos3250 SoC. Exynos3250 divides the buses to power line (regulator). The MIF (Memory Interface) AXI bus is used to transfer data between DRAM and CPU and uses the VDD_MIF regulator. @@ -184,7 +197,7 @@ Example1: |L5 |200000 |200000 |400000 |300000 | ||1000000 | ---------------------------------------------------------- -Example2 : +Example 2: The bus of DMC (Dynamic Memory Controller) block in exynos3250.dtsi is listed below: @@ -419,3 +432,57 @@ Example2 : devfreq = <&bus_leftbus>; status = "okay"; }; + +Example 3: + An interconnect path "bus_display -- bus_leftbus -- bus_dmc" on + Exynos4412 SoC with video mixer as an interconnect consumer device. + + soc { + bus_dmc: bus_dmc { + compatible = "samsung,exynos-bus"; + clocks = <&clock CLK_DIV_DMC>; + clock-names = "bus"; + operating-points-v2 = <&bus_dmc_opp_table>; + samsung,data-clock-ratio = <4>; + #interconnect-cells = <0>; + }; + + bus_leftbus: bus_leftbus { + compatible = "samsung,exynos-bus"; + clocks = <&clock CLK_DIV_GDL>; + clock-names = "bus"; + operating-points-v2 = <&bus_leftbus_opp_table>; + #interconnect-cells = <0>; + interconnects = <&bus_dmc>; + }; + + bus_display: bus_display { + compatible = "samsung,exynos-bus"; + clocks = <&clock CLK_ACLK160>; + clock-names = "bus"; + operating-points-v2 = <&bus_display_opp_table>; + #interconnect-cells = <0>; + interconnects = <&bus_leftbus &bus_dmc>; + }; + + bus_dmc_opp_table: opp_table1 { + compatible = "operating-points-v2"; + /* ... */ + } + + bus_leftbus_opp_table: opp_table3 { + compatible = "operating-points-v2"; + /* ... */ + }; + + bus_display_opp_table: opp_table4 { + compatible = "operating-points-v2"; + /* .. */ + }; + + &mixer { + compatible = "samsung,exynos4212-mixer"; + interconnects = <&bus_display &bus_dmc>; + /* ... */ + }; + }; diff --git a/Documentation/devicetree/bindings/display/brcm,bcm2711-hdmi.yaml b/Documentation/devicetree/bindings/display/brcm,bcm2711-hdmi.yaml index 03a76729d26c..7ce06f9f9f8e 100644 --- a/Documentation/devicetree/bindings/display/brcm,bcm2711-hdmi.yaml +++ b/Documentation/devicetree/bindings/display/brcm,bcm2711-hdmi.yaml @@ -76,6 +76,12 @@ properties: resets: maxItems: 1 + wifi-2.4ghz-coexistence: + type: boolean + description: > + Should the pixel frequencies in the WiFi frequencies range be + avoided? + required: - compatible - reg diff --git a/Documentation/devicetree/bindings/net/can/tcan4x5x.txt b/Documentation/devicetree/bindings/net/can/tcan4x5x.txt index 3613c2c8f75d..0968b40aef1e 100644 --- a/Documentation/devicetree/bindings/net/can/tcan4x5x.txt +++ b/Documentation/devicetree/bindings/net/can/tcan4x5x.txt @@ -33,7 +33,7 @@ tcan4x5x: tcan4x5x@0 { spi-max-frequency = <10000000>; bosch,mram-cfg = <0x0 0 0 32 0 0 1 1>; interrupt-parent = <&gpio1>; - interrupts = <14 GPIO_ACTIVE_LOW>; + interrupts = <14 IRQ_TYPE_LEVEL_LOW>; device-state-gpios = <&gpio3 21 GPIO_ACTIVE_HIGH>; device-wake-gpios = <&gpio1 15 GPIO_ACTIVE_HIGH>; reset-gpios = <&gpio1 27 GPIO_ACTIVE_HIGH>; diff --git a/Documentation/devicetree/bindings/net/nfc/nxp-nci.txt b/Documentation/devicetree/bindings/net/nfc/nxp-nci.txt index cfaf88998918..9e4dc510a40a 100644 --- a/Documentation/devicetree/bindings/net/nfc/nxp-nci.txt +++ b/Documentation/devicetree/bindings/net/nfc/nxp-nci.txt @@ -25,7 +25,7 @@ Example (for ARM-based BeagleBone with NPC100 NFC controller on I2C2): clock-frequency = <100000>; interrupt-parent = <&gpio1>; - interrupts = <29 GPIO_ACTIVE_HIGH>; + interrupts = <29 IRQ_TYPE_LEVEL_HIGH>; enable-gpios = <&gpio0 30 GPIO_ACTIVE_HIGH>; firmware-gpios = <&gpio0 31 GPIO_ACTIVE_HIGH>; diff --git a/Documentation/devicetree/bindings/net/nfc/pn544.txt b/Documentation/devicetree/bindings/net/nfc/pn544.txt index 92f399ec22b8..2bd82562ce8e 100644 --- a/Documentation/devicetree/bindings/net/nfc/pn544.txt +++ b/Documentation/devicetree/bindings/net/nfc/pn544.txt @@ -25,7 +25,7 @@ Example (for ARM-based BeagleBone with PN544 on I2C2): clock-frequency = <400000>; interrupt-parent = <&gpio1>; - interrupts = <17 GPIO_ACTIVE_HIGH>; + interrupts = <17 IRQ_TYPE_LEVEL_HIGH>; enable-gpios = <&gpio3 21 GPIO_ACTIVE_HIGH>; firmware-gpios = <&gpio3 19 GPIO_ACTIVE_HIGH>; diff --git a/Documentation/devicetree/bindings/opp/opp.txt b/Documentation/devicetree/bindings/opp/opp.txt index 9847dfeeffcb..08b3da4736cf 100644 --- a/Documentation/devicetree/bindings/opp/opp.txt +++ b/Documentation/devicetree/bindings/opp/opp.txt @@ -65,7 +65,9 @@ Required properties: - OPP nodes: One or more OPP nodes describing voltage-current-frequency combinations. Their name isn't significant but their phandle can be used to - reference an OPP. + reference an OPP. These are mandatory except for the case where the OPP table + is present only to indicate dependency between devices using the opp-shared + property. Optional properties: - opp-shared: Indicates that device nodes using this OPP Table Node's phandle @@ -568,3 +570,53 @@ Example 6: opp-microvolt-<name>, opp-microamp-<name>: }; }; }; + +Example 7: Single cluster Quad-core ARM cortex A53, OPP points from firmware, +distinct clock controls but two sets of clock/voltage/current lines. + +/ { + cpus { + #address-cells = <2>; + #size-cells = <0>; + + cpu@0 { + compatible = "arm,cortex-a53"; + reg = <0x0 0x100>; + next-level-cache = <&A53_L2>; + clocks = <&dvfs_controller 0>; + operating-points-v2 = <&cpu_opp0_table>; + }; + cpu@1 { + compatible = "arm,cortex-a53"; + reg = <0x0 0x101>; + next-level-cache = <&A53_L2>; + clocks = <&dvfs_controller 1>; + operating-points-v2 = <&cpu_opp0_table>; + }; + cpu@2 { + compatible = "arm,cortex-a53"; + reg = <0x0 0x102>; + next-level-cache = <&A53_L2>; + clocks = <&dvfs_controller 2>; + operating-points-v2 = <&cpu_opp1_table>; + }; + cpu@3 { + compatible = "arm,cortex-a53"; + reg = <0x0 0x103>; + next-level-cache = <&A53_L2>; + clocks = <&dvfs_controller 3>; + operating-points-v2 = <&cpu_opp1_table>; + }; + + }; + + cpu_opp0_table: opp0_table { + compatible = "operating-points-v2"; + opp-shared; + }; + + cpu_opp1_table: opp1_table { + compatible = "operating-points-v2"; + opp-shared; + }; +}; diff --git a/Documentation/driver-api/media/drivers/vidtv.rst b/Documentation/driver-api/media/drivers/vidtv.rst index 65115448c52d..673bdff919ea 100644 --- a/Documentation/driver-api/media/drivers/vidtv.rst +++ b/Documentation/driver-api/media/drivers/vidtv.rst @@ -149,11 +149,11 @@ vidtv_psi.[ch] Because the generator is implemented in a separate file, it can be reused elsewhere in the media subsystem. - Currently vidtv supports working with 3 PSI tables: PAT, PMT and - SDT. + Currently vidtv supports working with 5 PSI tables: PAT, PMT, + SDT, NIT and EIT. The specification for PAT and PMT can be found in *ISO 13818-1: - Systems*, while the specification for the SDT can be found in *ETSI + Systems*, while the specification for the SDT, NIT, EIT can be found in *ETSI EN 300 468: Specification for Service Information (SI) in DVB systems*. @@ -197,6 +197,8 @@ vidtv_channel.[ch] #. Their programs will be concatenated to populate the PAT + #. Their events will be concatenated to populate the EIT + #. For each program in the PAT, a PMT section will be created #. The PMT section for a channel will be assigned its streams. @@ -256,6 +258,42 @@ Using dvb-fe-tool The first step to check whether the demod loaded successfully is to run:: $ dvb-fe-tool + Device Dummy demod for DVB-T/T2/C/S/S2 (/dev/dvb/adapter0/frontend0) capabilities: + CAN_FEC_1_2 + CAN_FEC_2_3 + CAN_FEC_3_4 + CAN_FEC_4_5 + CAN_FEC_5_6 + CAN_FEC_6_7 + CAN_FEC_7_8 + CAN_FEC_8_9 + CAN_FEC_AUTO + CAN_GUARD_INTERVAL_AUTO + CAN_HIERARCHY_AUTO + CAN_INVERSION_AUTO + CAN_QAM_16 + CAN_QAM_32 + CAN_QAM_64 + CAN_QAM_128 + CAN_QAM_256 + CAN_QAM_AUTO + CAN_QPSK + CAN_TRANSMISSION_MODE_AUTO + DVB API Version 5.11, Current v5 delivery system: DVBC/ANNEX_A + Supported delivery systems: + DVBT + DVBT2 + [DVBC/ANNEX_A] + DVBS + DVBS2 + Frequency range for the current standard: + From: 51.0 MHz + To: 2.15 GHz + Step: 62.5 kHz + Tolerance: 29.5 MHz + Symbol rate ranges for the current standard: + From: 1.00 MBauds + To: 45.0 MBauds This should return what is currently set up at the demod struct, i.e.:: @@ -314,7 +352,7 @@ For this, one should provide a configuration file known as a 'scan file', here's an example:: [Channel] - FREQUENCY = 330000000 + FREQUENCY = 474000000 MODULATION = QAM/AUTO SYMBOL_RATE = 6940000 INNER_FEC = AUTO @@ -335,6 +373,14 @@ You can browse scan tables online here: `dvb-scan-tables Assuming this channel is named 'channel.conf', you can then run:: $ dvbv5-scan channel.conf + dvbv5-scan ~/vidtv.conf + ERROR command BANDWIDTH_HZ (5) not found during retrieve + Cannot calc frequency shift. Either bandwidth/symbol-rate is unavailable (yet). + Scanning frequency #1 330000000 + (0x00) Signal= -68.00dBm + Scanning frequency #2 474000000 + Lock (0x1f) Signal= -34.45dBm C/N= 33.74dB UCB= 0 + Service Beethoven, provider LinuxTV.org: digital television For more information on dvb-scan, check its documentation online here: `dvb-scan Documentation <https://www.linuxtv.org/wiki/index.php/Dvbscan>`_. @@ -344,23 +390,38 @@ Using dvb-zap dvbv5-zap is a command line tool that can be used to record MPEG-TS to disk. The typical use is to tune into a channel and put it into record mode. The example -below - which is taken from the documentation - illustrates that:: +below - which is taken from the documentation - illustrates that\ [1]_:: - $ dvbv5-zap -c dvb_channel.conf "trilhas sonoras" -r - using demux '/dev/dvb/adapter0/demux0' + $ dvbv5-zap -c dvb_channel.conf "beethoven" -o music.ts -P -t 10 + using demux 'dvb0.demux0' reading channels from file 'dvb_channel.conf' - service has pid type 05: 204 - tuning to 573000000 Hz - audio pid 104 - dvb_set_pesfilter 104 - Lock (0x1f) Quality= Good Signal= 100.00% C/N= -13.80dB UCB= 70 postBER= 3.14x10^-3 PER= 0 - DVR interface '/dev/dvb/adapter0/dvr0' can now be opened + tuning to 474000000 Hz + pass all PID's to TS + dvb_set_pesfilter 8192 + dvb_dev_set_bufsize: buffer set to 6160384 + Lock (0x1f) Quality= Good Signal= -34.66dBm C/N= 33.41dB UCB= 0 postBER= 0 preBER= 1.05x10^-3 PER= 0 + Lock (0x1f) Quality= Good Signal= -34.57dBm C/N= 33.46dB UCB= 0 postBER= 0 preBER= 1.05x10^-3 PER= 0 + Record to file 'music.ts' started + received 24587768 bytes (2401 Kbytes/sec) + Lock (0x1f) Quality= Good Signal= -34.42dBm C/N= 33.89dB UCB= 0 postBER= 0 preBER= 2.44x10^-3 PER= 0 + +.. [1] In this example, it records 10 seconds with all program ID's stored + at the music.ts file. + -The channel can be watched by playing the contents of the DVR interface, with -some player that recognizes the MPEG-TS format, such as *mplayer* or *vlc*. +The channel can be watched by playing the contents of the stream with some +player that recognizes the MPEG-TS format, such as ``mplayer`` or ``vlc``. By playing the contents of the stream one can visually inspect the workings of -vidtv, e.g.:: +vidtv, e.g., to play a recorded TS file with:: + + $ mplayer music.ts + +or, alternatively, running this command on one terminal:: + + $ dvbv5-zap -c dvb_channel.conf "beethoven" -P -r & + +And, on a second terminal, playing the contents from DVR interface with:: $ mplayer /dev/dvb/adapter0/dvr0 @@ -423,3 +484,30 @@ A nice addition is to simulate some noise when the signal quality is bad by: - Updating the error statistics accordingly (e.g. BER, etc). - Simulating some noise in the encoded data. + +Functions and structs used within vidtv +--------------------------------------- + +.. kernel-doc:: drivers/media/test-drivers/vidtv/vidtv_bridge.h + +.. kernel-doc:: drivers/media/test-drivers/vidtv/vidtv_channel.h + +.. kernel-doc:: drivers/media/test-drivers/vidtv/vidtv_demod.h + +.. kernel-doc:: drivers/media/test-drivers/vidtv/vidtv_encoder.h + +.. kernel-doc:: drivers/media/test-drivers/vidtv/vidtv_mux.h + +.. kernel-doc:: drivers/media/test-drivers/vidtv/vidtv_pes.h + +.. kernel-doc:: drivers/media/test-drivers/vidtv/vidtv_psi.h + +.. kernel-doc:: drivers/media/test-drivers/vidtv/vidtv_s302m.h + +.. kernel-doc:: drivers/media/test-drivers/vidtv/vidtv_ts.h + +.. kernel-doc:: drivers/media/test-drivers/vidtv/vidtv_tuner.h + +.. kernel-doc:: drivers/media/test-drivers/vidtv/vidtv_common.c + +.. kernel-doc:: drivers/media/test-drivers/vidtv/vidtv_tuner.c diff --git a/Documentation/driver-api/thermal/power_allocator.rst b/Documentation/driver-api/thermal/power_allocator.rst index 67b6a3297238..aa5f66552d6f 100644 --- a/Documentation/driver-api/thermal/power_allocator.rst +++ b/Documentation/driver-api/thermal/power_allocator.rst @@ -71,7 +71,9 @@ to the speed-grade of the silicon. `sustainable_power` is therefore simply an estimate, and may be tuned to affect the aggressiveness of the thermal ramp. For reference, the sustainable power of a 4" phone is typically 2000mW, while on a 10" tablet is around 4500mW (may vary -depending on screen size). +depending on screen size). It is possible to have the power value +expressed in an abstract scale. The sustained power should be aligned +to the scale used by the related cooling devices. If you are using device tree, do add it as a property of the thermal-zone. For example:: @@ -269,3 +271,11 @@ won't be very good. Note that this is not particular to this governor, step-wise will also misbehave if you call its throttle() faster than the normal thermal framework tick (due to interrupts for example) as it will overreact. + +Energy Model requirements +========================= + +Another important thing is the consistent scale of the power values +provided by the cooling devices. All of the cooling devices in a single +thermal zone should have power values reported either in milli-Watts +or scaled to the same 'abstract scale'. diff --git a/Documentation/kbuild/llvm.rst b/Documentation/kbuild/llvm.rst index cf3ca236d2cc..21c847890d03 100644 --- a/Documentation/kbuild/llvm.rst +++ b/Documentation/kbuild/llvm.rst @@ -57,9 +57,8 @@ to enable them. :: They can be enabled individually. The full list of the parameters: :: make CC=clang LD=ld.lld AR=llvm-ar NM=llvm-nm STRIP=llvm-strip \ - OBJCOPY=llvm-objcopy OBJDUMP=llvm-objdump OBJSIZE=llvm-size \ - READELF=llvm-readelf HOSTCC=clang HOSTCXX=clang++ HOSTAR=llvm-ar \ - HOSTLD=ld.lld + OBJCOPY=llvm-objcopy OBJDUMP=llvm-objdump READELF=llvm-readelf \ + HOSTCC=clang HOSTCXX=clang++ HOSTAR=llvm-ar HOSTLD=ld.lld Currently, the integrated assembler is disabled by default. You can pass ``LLVM_IAS=1`` to enable it. diff --git a/Documentation/networking/netdev-FAQ.rst b/Documentation/networking/netdev-FAQ.rst index 21537766be4d..4b9ed5874d5a 100644 --- a/Documentation/networking/netdev-FAQ.rst +++ b/Documentation/networking/netdev-FAQ.rst @@ -254,6 +254,32 @@ you will have done run-time testing specific to your change, but at a minimum, your changes should survive an ``allyesconfig`` and an ``allmodconfig`` build without new warnings or failures. +Q: How do I post corresponding changes to user space components? +---------------------------------------------------------------- +A: User space code exercising kernel features should be posted +alongside kernel patches. This gives reviewers a chance to see +how any new interface is used and how well it works. + +When user space tools reside in the kernel repo itself all changes +should generally come as one series. If series becomes too large +or the user space project is not reviewed on netdev include a link +to a public repo where user space patches can be seen. + +In case user space tooling lives in a separate repository but is +reviewed on netdev (e.g. patches to `iproute2` tools) kernel and +user space patches should form separate series (threads) when posted +to the mailing list, e.g.:: + + [PATCH net-next 0/3] net: some feature cover letter + └─ [PATCH net-next 1/3] net: some feature prep + └─ [PATCH net-next 2/3] net: some feature do it + └─ [PATCH net-next 3/3] selftest: net: some feature + + [PATCH iproute2-next] ip: add support for some feature + +Posting as one thread is discouraged because it confuses patchwork +(as of patchwork 2.2.2). + Q: Any other tips to help ensure my net/net-next patch gets OK'd? ----------------------------------------------------------------- A: Attention to detail. Re-read your own work as if you were the diff --git a/Documentation/power/energy-model.rst b/Documentation/power/energy-model.rst index a6fb986abe3c..60ac091d3b0d 100644 --- a/Documentation/power/energy-model.rst +++ b/Documentation/power/energy-model.rst @@ -20,6 +20,21 @@ possible source of information on its own, the EM framework intervenes as an abstraction layer which standardizes the format of power cost tables in the kernel, hence enabling to avoid redundant work. +The power values might be expressed in milli-Watts or in an 'abstract scale'. +Multiple subsystems might use the EM and it is up to the system integrator to +check that the requirements for the power value scale types are met. An example +can be found in the Energy-Aware Scheduler documentation +Documentation/scheduler/sched-energy.rst. For some subsystems like thermal or +powercap power values expressed in an 'abstract scale' might cause issues. +These subsystems are more interested in estimation of power used in the past, +thus the real milli-Watts might be needed. An example of these requirements can +be found in the Intelligent Power Allocation in +Documentation/driver-api/thermal/power_allocator.rst. +Kernel subsystems might implement automatic detection to check whether EM +registered devices have inconsistent scale (based on EM internal flag). +Important thing to keep in mind is that when the power values are expressed in +an 'abstract scale' deriving real energy in milli-Joules would not be possible. + The figure below depicts an example of drivers (Arm-specific here, but the approach is applicable to any architecture) providing power costs to the EM framework, and interested clients reading the data from it:: @@ -73,7 +88,7 @@ Drivers are expected to register performance domains into the EM framework by calling the following API:: int em_dev_register_perf_domain(struct device *dev, unsigned int nr_states, - struct em_data_callback *cb, cpumask_t *cpus); + struct em_data_callback *cb, cpumask_t *cpus, bool milliwatts); Drivers must provide a callback function returning <frequency, power> tuples for each performance state. The callback function provided by the driver is free @@ -81,6 +96,10 @@ to fetch data from any relevant location (DT, firmware, ...), and by any mean deemed necessary. Only for CPU devices, drivers must specify the CPUs of the performance domains using cpumask. For other devices than CPUs the last argument must be set to NULL. +The last argument 'milliwatts' is important to set with correct value. Kernel +subsystems which use EM might rely on this flag to check if all EM devices use +the same scale. If there are different scales, these subsystems might decide +to: return warning/error, stop working or panic. See Section 3. for an example of driver implementing this callback, and kernel/power/energy_model.c for further documentation on this API. @@ -156,7 +175,8 @@ EM framework:: 37 nr_opp = foo_get_nr_opp(policy); 38 39 /* And register the new performance domain */ - 40 em_dev_register_perf_domain(cpu_dev, nr_opp, &em_cb, policy->cpus); - 41 - 42 return 0; - 43 } + 40 em_dev_register_perf_domain(cpu_dev, nr_opp, &em_cb, policy->cpus, + 41 true); + 42 + 43 return 0; + 44 } diff --git a/Documentation/scheduler/sched-energy.rst b/Documentation/scheduler/sched-energy.rst index 001e09c95e1d..afe02d394402 100644 --- a/Documentation/scheduler/sched-energy.rst +++ b/Documentation/scheduler/sched-energy.rst @@ -350,6 +350,11 @@ independent EM framework in Documentation/power/energy-model.rst. Please also note that the scheduling domains need to be re-built after the EM has been registered in order to start EAS. +EAS uses the EM to make a forecasting decision on energy usage and thus it is +more focused on the difference when checking possible options for task +placement. For EAS it doesn't matter whether the EM power values are expressed +in milli-Watts or in an 'abstract scale'. + 6.3 - Energy Model complexity ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ |