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authorLinus Torvalds <torvalds@linux-foundation.org>2012-12-13 19:59:11 +0100
committerLinus Torvalds <torvalds@linux-foundation.org>2012-12-13 19:59:11 +0100
commit698d601224824bc1a5bf17f3d86be902e2aabff0 (patch)
tree10262bd1f83fd26f874cbd898818e5925844a2ef /Documentation
parentMerge tag 'pm-merge' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm... (diff)
parentMerge branch 'next/gpio-samsung' of git://git.kernel.org/pub/scm/linux/kernel... (diff)
downloadlinux-698d601224824bc1a5bf17f3d86be902e2aabff0.tar.xz
linux-698d601224824bc1a5bf17f3d86be902e2aabff0.zip
Merge tag 'drivers' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
Pull ARM SoC driver specific changes from Olof Johansson: "A collection of mostly SoC-specific driver updates: - a handful of pincontrol and setup changes - new drivers for hwmon and reset controller for vexpress - timing support updates for OMAP (gpmc and other interfaces) - plus a collection of smaller cleanups" * tag 'drivers' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (21 commits) ARM: ux500: fix pin warning ARM: OMAP2+: tusb6010: generic timing calculation ARM: OMAP2+: smc91x: generic timing calculation ARM: OMAP2+: onenand: generic timing calculation ARM: OMAP2+: gpmc: generic timing calculation ARM: OMAP2+: gpmc: handle additional timings ARM: OMAP2+: nand: remove redundant rounding gpio: samsung: use pr_* instead of printk ARM: ux500: fixup magnetometer pins ARM: ux500: add STM pin configuration ARM: ux500: 8500: add pinctrl support for uart1 and uart2 ARM: ux500: cosmetic fixups for uart0 gpio: samsung: Fix input mode setting function for GPIO int ARM: SAMSUNG: Insert bitmap_gpio_int member in samsung_gpio_chip ARM: ux500: 8500: define SDI sleep states ARM: vexpress: Reset driver ARM: ux500: 8500: update SKE keypad pinctrl table hwmon: Versatile Express hwmon driver ARM: ux500: delete duplicate macro ARM: ux500: 8500: add IDLE pin configuration for SPI ...
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/bus-devices/ti-gpmc.txt122
-rw-r--r--Documentation/devicetree/bindings/hwmon/vexpress.txt23
-rw-r--r--Documentation/hwmon/vexpress34
3 files changed, 179 insertions, 0 deletions
diff --git a/Documentation/bus-devices/ti-gpmc.txt b/Documentation/bus-devices/ti-gpmc.txt
new file mode 100644
index 000000000000..cc9ce57e0a26
--- /dev/null
+++ b/Documentation/bus-devices/ti-gpmc.txt
@@ -0,0 +1,122 @@
+GPMC (General Purpose Memory Controller):
+=========================================
+
+GPMC is an unified memory controller dedicated to interfacing external
+memory devices like
+ * Asynchronous SRAM like memories and application specific integrated
+ circuit devices.
+ * Asynchronous, synchronous, and page mode burst NOR flash devices
+ NAND flash
+ * Pseudo-SRAM devices
+
+GPMC is found on Texas Instruments SoC's (OMAP based)
+IP details: http://www.ti.com/lit/pdf/spruh73 section 7.1
+
+
+GPMC generic timing calculation:
+================================
+
+GPMC has certain timings that has to be programmed for proper
+functioning of the peripheral, while peripheral has another set of
+timings. To have peripheral work with gpmc, peripheral timings has to
+be translated to the form gpmc can understand. The way it has to be
+translated depends on the connected peripheral. Also there is a
+dependency for certain gpmc timings on gpmc clock frequency. Hence a
+generic timing routine was developed to achieve above requirements.
+
+Generic routine provides a generic method to calculate gpmc timings
+from gpmc peripheral timings. struct gpmc_device_timings fields has to
+be updated with timings from the datasheet of the peripheral that is
+connected to gpmc. A few of the peripheral timings can be fed either
+in time or in cycles, provision to handle this scenario has been
+provided (refer struct gpmc_device_timings definition). It may so
+happen that timing as specified by peripheral datasheet is not present
+in timing structure, in this scenario, try to correlate peripheral
+timing to the one available. If that doesn't work, try to add a new
+field as required by peripheral, educate generic timing routine to
+handle it, make sure that it does not break any of the existing.
+Then there may be cases where peripheral datasheet doesn't mention
+certain fields of struct gpmc_device_timings, zero those entries.
+
+Generic timing routine has been verified to work properly on
+multiple onenand's and tusb6010 peripherals.
+
+A word of caution: generic timing routine has been developed based
+on understanding of gpmc timings, peripheral timings, available
+custom timing routines, a kind of reverse engineering without
+most of the datasheets & hardware (to be exact none of those supported
+in mainline having custom timing routine) and by simulation.
+
+gpmc timing dependency on peripheral timings:
+[<gpmc_timing>: <peripheral timing1>, <peripheral timing2> ...]
+
+1. common
+cs_on: t_ceasu
+adv_on: t_avdasu, t_ceavd
+
+2. sync common
+sync_clk: clk
+page_burst_access: t_bacc
+clk_activation: t_ces, t_avds
+
+3. read async muxed
+adv_rd_off: t_avdp_r
+oe_on: t_oeasu, t_aavdh
+access: t_iaa, t_oe, t_ce, t_aa
+rd_cycle: t_rd_cycle, t_cez_r, t_oez
+
+4. read async non-muxed
+adv_rd_off: t_avdp_r
+oe_on: t_oeasu
+access: t_iaa, t_oe, t_ce, t_aa
+rd_cycle: t_rd_cycle, t_cez_r, t_oez
+
+5. read sync muxed
+adv_rd_off: t_avdp_r, t_avdh
+oe_on: t_oeasu, t_ach, cyc_aavdh_oe
+access: t_iaa, cyc_iaa, cyc_oe
+rd_cycle: t_cez_r, t_oez, t_ce_rdyz
+
+6. read sync non-muxed
+adv_rd_off: t_avdp_r
+oe_on: t_oeasu
+access: t_iaa, cyc_iaa, cyc_oe
+rd_cycle: t_cez_r, t_oez, t_ce_rdyz
+
+7. write async muxed
+adv_wr_off: t_avdp_w
+we_on, wr_data_mux_bus: t_weasu, t_aavdh, cyc_aavhd_we
+we_off: t_wpl
+cs_wr_off: t_wph
+wr_cycle: t_cez_w, t_wr_cycle
+
+8. write async non-muxed
+adv_wr_off: t_avdp_w
+we_on, wr_data_mux_bus: t_weasu
+we_off: t_wpl
+cs_wr_off: t_wph
+wr_cycle: t_cez_w, t_wr_cycle
+
+9. write sync muxed
+adv_wr_off: t_avdp_w, t_avdh
+we_on, wr_data_mux_bus: t_weasu, t_rdyo, t_aavdh, cyc_aavhd_we
+we_off: t_wpl, cyc_wpl
+cs_wr_off: t_wph
+wr_cycle: t_cez_w, t_ce_rdyz
+
+10. write sync non-muxed
+adv_wr_off: t_avdp_w
+we_on, wr_data_mux_bus: t_weasu, t_rdyo
+we_off: t_wpl, cyc_wpl
+cs_wr_off: t_wph
+wr_cycle: t_cez_w, t_ce_rdyz
+
+
+Note: Many of gpmc timings are dependent on other gpmc timings (a few
+gpmc timings purely dependent on other gpmc timings, a reason that
+some of the gpmc timings are missing above), and it will result in
+indirect dependency of peripheral timings to gpmc timings other than
+mentioned above, refer timing routine for more details. To know what
+these peripheral timings correspond to, please see explanations in
+struct gpmc_device_timings definition. And for gpmc timings refer
+IP details (link above).
diff --git a/Documentation/devicetree/bindings/hwmon/vexpress.txt b/Documentation/devicetree/bindings/hwmon/vexpress.txt
new file mode 100644
index 000000000000..9c27ed694bbb
--- /dev/null
+++ b/Documentation/devicetree/bindings/hwmon/vexpress.txt
@@ -0,0 +1,23 @@
+Versatile Express hwmon sensors
+-------------------------------
+
+Requires node properties:
+- "compatible" value : one of
+ "arm,vexpress-volt"
+ "arm,vexpress-amp"
+ "arm,vexpress-temp"
+ "arm,vexpress-power"
+ "arm,vexpress-energy"
+- "arm,vexpress-sysreg,func" when controlled via vexpress-sysreg
+ (see Documentation/devicetree/bindings/arm/vexpress-sysreg.txt
+ for more details)
+
+Optional node properties:
+- label : string describing the monitored value
+
+Example:
+ energy@0 {
+ compatible = "arm,vexpress-energy";
+ arm,vexpress-sysreg,func = <13 0>;
+ label = "A15 Jcore";
+ };
diff --git a/Documentation/hwmon/vexpress b/Documentation/hwmon/vexpress
new file mode 100644
index 000000000000..557d6d5ad90d
--- /dev/null
+++ b/Documentation/hwmon/vexpress
@@ -0,0 +1,34 @@
+Kernel driver vexpress
+======================
+
+Supported systems:
+ * ARM Ltd. Versatile Express platform
+ Prefix: 'vexpress'
+ Datasheets:
+ * "Hardware Description" sections of the Technical Reference Manuals
+ for the Versatile Express boards:
+ http://infocenter.arm.com/help/topic/com.arm.doc.subset.boards.express/index.html
+ * Section "4.4.14. System Configuration registers" of the V2M-P1 TRM:
+ http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.dui0447-/index.html
+
+Author: Pawel Moll
+
+Description
+-----------
+
+Versatile Express platform (http://www.arm.com/versatileexpress/) is a
+reference & prototyping system for ARM Ltd. processors. It can be set up
+from a wide range of boards, each of them containing (apart of the main
+chip/FPGA) a number of microcontrollers responsible for platform
+configuration and control. Theses microcontrollers can also monitor the
+board and its environment by a number of internal and external sensors,
+providing information about power lines voltages and currents, board
+temperature and power usage. Some of them also calculate consumed energy
+and provide a cumulative use counter.
+
+The configuration devices are _not_ memory mapped and must be accessed
+via a custom interface, abstracted by the "vexpress_config" API.
+
+As these devices are non-discoverable, they must be described in a Device
+Tree passed to the kernel. Details of the DT binding for them can be found
+in Documentation/devicetree/bindings/hwmon/vexpress.txt.