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authorLinus Torvalds <torvalds@linux-foundation.org>2013-04-30 03:43:54 +0400
committerLinus Torvalds <torvalds@linux-foundation.org>2013-04-30 03:43:54 +0400
commit362ed48dee509abe24cf84b7e137c7a29a8f4d2d (patch)
treef2c2397afa517becf3ff3d8ac4c5c542dfed9795 /Documentation
parent61f3d0a9883d965b498edeb673235bddc92770fd (diff)
parent1e435256d625c203660f0105f1155cd2af283051 (diff)
downloadlinux-362ed48dee509abe24cf84b7e137c7a29a8f4d2d.tar.xz
Merge tag 'clk-for-linus-3.10' of git://git.linaro.org/people/mturquette/linux
Pull clock framework update from Michael Turquette: "The common clock framework changes for 3.10 include many fixes for existing platforms, as well as adoption of the framework by new platforms and devices. Some long-needed fixes to the core framework are here as well as new features such as improved initialization of clocks from DT as well as framework reentrancy for nested clock operations." * tag 'clk-for-linus-3.10' of git://git.linaro.org/people/mturquette/linux: (44 commits) clk: add clk_ignore_unused option to keep boot clocks on clk: ux500: fix mismatched types clk: vexpress: Add separate SP810 driver clk: si5351: make clk-si5351 depend on CONFIG_OF clk: export __clk_get_flags for modular clock providers clk: vt8500: Missing breaks in vtwm_pll_round_rate/_set_rate. clk: sunxi: Unify oscillator clock clk: composite: allow fixed rates & fixed dividers clk: composite: rename 'div' references to 'rate' clk: add si5351 i2c common clock driver clk: add device tree fixed-factor-clock binding support clk: Properly handle notifier return values clk: ux500: abx500: Define clock tree for ab850x clk: ux500: Add support for sysctrl clocks clk: mvebu: Fix valid value range checking for cpu_freq_select clk: Fixup locking issues for clk_set_parent clk: Fixup errorhandling for clk_set_parent clk: Restructure code for __clk_reparent clk: sunxi: drop an unnecesary kmalloc clk: sunxi: drop CLK_IGNORE_UNUSED ...
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/arm/sunxi/clocks.txt56
-rw-r--r--Documentation/clk.txt15
-rw-r--r--Documentation/devicetree/bindings/clock/axi-clkgen.txt22
-rw-r--r--Documentation/devicetree/bindings/clock/fixed-factor-clock.txt24
-rw-r--r--Documentation/devicetree/bindings/clock/silabs,si5351.txt114
-rw-r--r--Documentation/devicetree/bindings/clock/sunxi.txt151
-rw-r--r--Documentation/devicetree/bindings/vendor-prefixes.txt1
-rw-r--r--Documentation/kernel-parameters.txt8
8 files changed, 389 insertions, 2 deletions
diff --git a/Documentation/arm/sunxi/clocks.txt b/Documentation/arm/sunxi/clocks.txt
new file mode 100644
index 000000000000..e09a88aa3136
--- /dev/null
+++ b/Documentation/arm/sunxi/clocks.txt
@@ -0,0 +1,56 @@
+Frequently asked questions about the sunxi clock system
+=======================================================
+
+This document contains useful bits of information that people tend to ask
+about the sunxi clock system, as well as accompanying ASCII art when adequate.
+
+Q: Why is the main 24MHz oscillator gatable? Wouldn't that break the
+ system?
+
+A: The 24MHz oscillator allows gating to save power. Indeed, if gated
+ carelessly the system would stop functioning, but with the right
+ steps, one can gate it and keep the system running. Consider this
+ simplified suspend example:
+
+ While the system is operational, you would see something like
+
+ 24MHz 32kHz
+ |
+ PLL1
+ \
+ \_ CPU Mux
+ |
+ [CPU]
+
+ When you are about to suspend, you switch the CPU Mux to the 32kHz
+ oscillator:
+
+ 24Mhz 32kHz
+ | |
+ PLL1 |
+ /
+ CPU Mux _/
+ |
+ [CPU]
+
+ Finally you can gate the main oscillator
+
+ 32kHz
+ |
+ |
+ /
+ CPU Mux _/
+ |
+ [CPU]
+
+Q: Were can I learn more about the sunxi clocks?
+
+A: The linux-sunxi wiki contains a page documenting the clock registers,
+ you can find it at
+
+ http://linux-sunxi.org/A10/CCM
+
+ The authoritative source for information at this time is the ccmu driver
+ released by Allwinner, you can find it at
+
+ https://github.com/linux-sunxi/linux-sunxi/tree/sunxi-3.0/arch/arm/mach-sun4i/clock/ccmu
diff --git a/Documentation/clk.txt b/Documentation/clk.txt
index 1943fae014fd..b9911c27f496 100644
--- a/Documentation/clk.txt
+++ b/Documentation/clk.txt
@@ -174,9 +174,9 @@ int clk_foo_enable(struct clk_hw *hw)
};
Below is a matrix detailing which clk_ops are mandatory based upon the
-hardware capbilities of that clock. A cell marked as "y" means
+hardware capabilities of that clock. A cell marked as "y" means
mandatory, a cell marked as "n" implies that either including that
-callback is invalid or otherwise uneccesary. Empty cells are either
+callback is invalid or otherwise unnecessary. Empty cells are either
optional or must be evaluated on a case-by-case basis.
clock hardware characteristics
@@ -231,3 +231,14 @@ To better enforce this policy, always follow this simple rule: any
statically initialized clock data MUST be defined in a separate file
from the logic that implements its ops. Basically separate the logic
from the data and all is well.
+
+ Part 6 - Disabling clock gating of unused clocks
+
+Sometimes during development it can be useful to be able to bypass the
+default disabling of unused clocks. For example, if drivers aren't enabling
+clocks properly but rely on them being on from the bootloader, bypassing
+the disabling means that the driver will remain functional while the issues
+are sorted out.
+
+To bypass this disabling, include "clk_ignore_unused" in the bootargs to the
+kernel.
diff --git a/Documentation/devicetree/bindings/clock/axi-clkgen.txt b/Documentation/devicetree/bindings/clock/axi-clkgen.txt
new file mode 100644
index 000000000000..028b493e97ff
--- /dev/null
+++ b/Documentation/devicetree/bindings/clock/axi-clkgen.txt
@@ -0,0 +1,22 @@
+Binding for the axi-clkgen clock generator
+
+This binding uses the common clock binding[1].
+
+[1] Documentation/devicetree/bindings/clock/clock-bindings.txt
+
+Required properties:
+- compatible : shall be "adi,axi-clkgen".
+- #clock-cells : from common clock binding; Should always be set to 0.
+- reg : Address and length of the axi-clkgen register set.
+- clocks : Phandle and clock specifier for the parent clock.
+
+Optional properties:
+- clock-output-names : From common clock binding.
+
+Example:
+ clock@0xff000000 {
+ compatible = "adi,axi-clkgen";
+ #clock-cells = <0>;
+ reg = <0xff000000 0x1000>;
+ clocks = <&osc 1>;
+ };
diff --git a/Documentation/devicetree/bindings/clock/fixed-factor-clock.txt b/Documentation/devicetree/bindings/clock/fixed-factor-clock.txt
new file mode 100644
index 000000000000..5757f9abfc26
--- /dev/null
+++ b/Documentation/devicetree/bindings/clock/fixed-factor-clock.txt
@@ -0,0 +1,24 @@
+Binding for simple fixed factor rate clock sources.
+
+This binding uses the common clock binding[1].
+
+[1] Documentation/devicetree/bindings/clock/clock-bindings.txt
+
+Required properties:
+- compatible : shall be "fixed-factor-clock".
+- #clock-cells : from common clock binding; shall be set to 0.
+- clock-div: fixed divider.
+- clock-mult: fixed multiplier.
+- clocks: parent clock.
+
+Optional properties:
+- clock-output-names : From common clock binding.
+
+Example:
+ clock {
+ compatible = "fixed-factor-clock";
+ clocks = <&parentclk>;
+ #clock-cells = <0>;
+ div = <2>;
+ mult = <1>;
+ };
diff --git a/Documentation/devicetree/bindings/clock/silabs,si5351.txt b/Documentation/devicetree/bindings/clock/silabs,si5351.txt
new file mode 100644
index 000000000000..cc374651662c
--- /dev/null
+++ b/Documentation/devicetree/bindings/clock/silabs,si5351.txt
@@ -0,0 +1,114 @@
+Binding for Silicon Labs Si5351a/b/c programmable i2c clock generator.
+
+Reference
+[1] Si5351A/B/C Data Sheet
+ http://www.silabs.com/Support%20Documents/TechnicalDocs/Si5351.pdf
+
+The Si5351a/b/c are programmable i2c clock generators with upto 8 output
+clocks. Si5351a also has a reduced pin-count package (MSOP10) where only
+3 output clocks are accessible. The internal structure of the clock
+generators can be found in [1].
+
+==I2C device node==
+
+Required properties:
+- compatible: shall be one of "silabs,si5351{a,a-msop,b,c}".
+- reg: i2c device address, shall be 0x60 or 0x61.
+- #clock-cells: from common clock binding; shall be set to 1.
+- clocks: from common clock binding; list of parent clock
+ handles, shall be xtal reference clock or xtal and clkin for
+ si5351c only.
+- #address-cells: shall be set to 1.
+- #size-cells: shall be set to 0.
+
+Optional properties:
+- silabs,pll-source: pair of (number, source) for each pll. Allows
+ to overwrite clock source of pll A (number=0) or B (number=1).
+
+==Child nodes==
+
+Each of the clock outputs can be overwritten individually by
+using a child node to the I2C device node. If a child node for a clock
+output is not set, the eeprom configuration is not overwritten.
+
+Required child node properties:
+- reg: number of clock output.
+
+Optional child node properties:
+- silabs,clock-source: source clock of the output divider stage N, shall be
+ 0 = multisynth N
+ 1 = multisynth 0 for output clocks 0-3, else multisynth4
+ 2 = xtal
+ 3 = clkin (si5351c only)
+- silabs,drive-strength: output drive strength in mA, shall be one of {2,4,6,8}.
+- silabs,multisynth-source: source pll A(0) or B(1) of corresponding multisynth
+ divider.
+- silabs,pll-master: boolean, multisynth can change pll frequency.
+
+==Example==
+
+/* 25MHz reference crystal */
+ref25: ref25M {
+ compatible = "fixed-clock";
+ #clock-cells = <0>;
+ clock-frequency = <25000000>;
+};
+
+i2c-master-node {
+
+ /* Si5351a msop10 i2c clock generator */
+ si5351a: clock-generator@60 {
+ compatible = "silabs,si5351a-msop";
+ reg = <0x60>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+ #clock-cells = <1>;
+
+ /* connect xtal input to 25MHz reference */
+ clocks = <&ref25>;
+
+ /* connect xtal input as source of pll0 and pll1 */
+ silabs,pll-source = <0 0>, <1 0>;
+
+ /*
+ * overwrite clkout0 configuration with:
+ * - 8mA output drive strength
+ * - pll0 as clock source of multisynth0
+ * - multisynth0 as clock source of output divider
+ * - multisynth0 can change pll0
+ * - set initial clock frequency of 74.25MHz
+ */
+ clkout0 {
+ reg = <0>;
+ silabs,drive-strength = <8>;
+ silabs,multisynth-source = <0>;
+ silabs,clock-source = <0>;
+ silabs,pll-master;
+ clock-frequency = <74250000>;
+ };
+
+ /*
+ * overwrite clkout1 configuration with:
+ * - 4mA output drive strength
+ * - pll1 as clock source of multisynth1
+ * - multisynth1 as clock source of output divider
+ * - multisynth1 can change pll1
+ */
+ clkout1 {
+ reg = <1>;
+ silabs,drive-strength = <4>;
+ silabs,multisynth-source = <1>;
+ silabs,clock-source = <0>;
+ pll-master;
+ };
+
+ /*
+ * overwrite clkout2 configuration with:
+ * - xtal as clock source of output divider
+ */
+ clkout2 {
+ reg = <2>;
+ silabs,clock-source = <2>;
+ };
+ };
+};
diff --git a/Documentation/devicetree/bindings/clock/sunxi.txt b/Documentation/devicetree/bindings/clock/sunxi.txt
new file mode 100644
index 000000000000..729f52426fe1
--- /dev/null
+++ b/Documentation/devicetree/bindings/clock/sunxi.txt
@@ -0,0 +1,151 @@
+Device Tree Clock bindings for arch-sunxi
+
+This binding uses the common clock binding[1].
+
+[1] Documentation/devicetree/bindings/clock/clock-bindings.txt
+
+Required properties:
+- compatible : shall be one of the following:
+ "allwinner,sun4i-osc-clk" - for a gatable oscillator
+ "allwinner,sun4i-pll1-clk" - for the main PLL clock
+ "allwinner,sun4i-cpu-clk" - for the CPU multiplexer clock
+ "allwinner,sun4i-axi-clk" - for the AXI clock
+ "allwinner,sun4i-axi-gates-clk" - for the AXI gates
+ "allwinner,sun4i-ahb-clk" - for the AHB clock
+ "allwinner,sun4i-ahb-gates-clk" - for the AHB gates
+ "allwinner,sun4i-apb0-clk" - for the APB0 clock
+ "allwinner,sun4i-apb0-gates-clk" - for the APB0 gates
+ "allwinner,sun4i-apb1-clk" - for the APB1 clock
+ "allwinner,sun4i-apb1-mux-clk" - for the APB1 clock muxing
+ "allwinner,sun4i-apb1-gates-clk" - for the APB1 gates
+
+Required properties for all clocks:
+- reg : shall be the control register address for the clock.
+- clocks : shall be the input parent clock(s) phandle for the clock
+- #clock-cells : from common clock binding; shall be set to 0 except for
+ "allwinner,sun4i-*-gates-clk" where it shall be set to 1
+
+Additionally, "allwinner,sun4i-*-gates-clk" clocks require:
+- clock-output-names : the corresponding gate names that the clock controls
+
+For example:
+
+osc24M: osc24M@01c20050 {
+ #clock-cells = <0>;
+ compatible = "allwinner,sun4i-osc-clk";
+ reg = <0x01c20050 0x4>;
+ clocks = <&osc24M_fixed>;
+};
+
+pll1: pll1@01c20000 {
+ #clock-cells = <0>;
+ compatible = "allwinner,sun4i-pll1-clk";
+ reg = <0x01c20000 0x4>;
+ clocks = <&osc24M>;
+};
+
+cpu: cpu@01c20054 {
+ #clock-cells = <0>;
+ compatible = "allwinner,sun4i-cpu-clk";
+ reg = <0x01c20054 0x4>;
+ clocks = <&osc32k>, <&osc24M>, <&pll1>;
+};
+
+
+
+Gate clock outputs
+
+The "allwinner,sun4i-*-gates-clk" clocks provide several gatable outputs;
+their corresponding offsets as present on sun4i are listed below. Note that
+some of these gates are not present on sun5i.
+
+ * AXI gates ("allwinner,sun4i-axi-gates-clk")
+
+ DRAM 0
+
+ * AHB gates ("allwinner,sun4i-ahb-gates-clk")
+
+ USB0 0
+ EHCI0 1
+ OHCI0 2*
+ EHCI1 3
+ OHCI1 4*
+ SS 5
+ DMA 6
+ BIST 7
+ MMC0 8
+ MMC1 9
+ MMC2 10
+ MMC3 11
+ MS 12**
+ NAND 13
+ SDRAM 14
+
+ ACE 16
+ EMAC 17
+ TS 18
+
+ SPI0 20
+ SPI1 21
+ SPI2 22
+ SPI3 23
+ PATA 24
+ SATA 25**
+ GPS 26*
+
+ VE 32
+ TVD 33
+ TVE0 34
+ TVE1 35
+ LCD0 36
+ LCD1 37
+
+ CSI0 40
+ CSI1 41
+
+ HDMI 43
+ DE_BE0 44
+ DE_BE1 45
+ DE_FE0 46
+ DE_FE1 47
+
+ MP 50
+
+ MALI400 52
+
+ * APB0 gates ("allwinner,sun4i-apb0-gates-clk")
+
+ CODEC 0
+ SPDIF 1*
+ AC97 2
+ IIS 3
+
+ PIO 5
+ IR0 6
+ IR1 7
+
+ KEYPAD 10
+
+ * APB1 gates ("allwinner,sun4i-apb1-gates-clk")
+
+ I2C0 0
+ I2C1 1
+ I2C2 2
+
+ CAN 4
+ SCR 5
+ PS20 6
+ PS21 7
+
+ UART0 16
+ UART1 17
+ UART2 18
+ UART3 19
+ UART4 20
+ UART5 21
+ UART6 22
+ UART7 23
+
+Notation:
+ [*]: The datasheet didn't mention these, but they are present on AW code
+ [**]: The datasheet had this marked as "NC" but they are used on AW code
diff --git a/Documentation/devicetree/bindings/vendor-prefixes.txt b/Documentation/devicetree/bindings/vendor-prefixes.txt
index 3b3b0194adfe..4d1919bf2332 100644
--- a/Documentation/devicetree/bindings/vendor-prefixes.txt
+++ b/Documentation/devicetree/bindings/vendor-prefixes.txt
@@ -49,6 +49,7 @@ samsung Samsung Semiconductor
sbs Smart Battery System
schindler Schindler
sil Silicon Image
+silabs Silicon Laboratories
simtek
sirf SiRF Technology, Inc.
snps Synopsys, Inc.
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 5abc09a93bc2..365f7bd40eeb 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -44,6 +44,7 @@ parameter is applicable:
AVR32 AVR32 architecture is enabled.
AX25 Appropriate AX.25 support is enabled.
BLACKFIN Blackfin architecture is enabled.
+ CLK Common clock infrastructure is enabled.
DRM Direct Rendering Management support is enabled.
DYNAMIC_DEBUG Build in debug messages and enable them at runtime
EDD BIOS Enhanced Disk Drive Services (EDD) is enabled
@@ -472,6 +473,13 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
cio_ignore= [S390]
See Documentation/s390/CommonIO for details.
+ clk_ignore_unused
+ [CLK]
+ Keep all clocks already enabled by bootloader on,
+ even if no driver has claimed them. This is useful
+ for debug and development, but should not be
+ needed on a platform with proper driver support.
+ For more information, see Documentation/clk.txt.
clock= [BUGS=X86-32, HW] gettimeofday clocksource override.
[Deprecated]