Merge branch 'omap-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap-2.6

* 'omap-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap-2.6: (47 commits)
  OMAP clock: use debugfs_remove_recursive() for rewinding
  OMAP2/3/4 core: create omap_device layer
  OMAP: omap_hwmod: call omap_hwmod init at boot; create interconnects
  OMAP2/3/4: create omap_hwmod layer
  OMAP2/3 board-*.c files: read bootloader configuration earlier
  OMAP2/3/4 PRCM: add module IDLEST wait code
  OMAP2/3 PM: create the OMAP PM interface and add a default OMAP PM no-op layer
  OMAP3 clock: remove superfluous calls to omap2_init_clk_clkdm
  OMAP clock: associate MPU clocks with the mpu_clkdm
  OMAP3 clock: Fixed processing of bootarg 'mpurate'
  OMAP: SDRC: Add several new register definitions
  OMAP: powerdomain: Fix overflow when doing powerdomain deps lookups.
  OMAP: PM: Added suspend target state control to debugfs for OMAP3
  OMAP: PM debug: Add PRCM register dump support
  OMAP: PM debug: make powerdomains use PM-debug counters
  OMAP: PM: Add pm-debug counters
  OMAP: PM: Add closures to clkdm_for_each and pwrdm_for_each.
  OMAP: PM: Hook into PM counters
  OMAP: PM counter infrastructure.
  OMAP3: PM: fix lockdep warning caused by omap3_pm_init
  ...

1 files changed, 129 insertions, 0 deletions

diff --git a/Documentation/arm/OMAP/omap_pm b/Documentation/arm/OMAP/omap_pm
new file mode 100644
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+
+The OMAP PM interface
+=====================
+
+This document describes the temporary OMAP PM interface.  Driver
+authors use these functions to communicate minimum latency or
+throughput constraints to the kernel power management code.
+Over time, the intention is to merge features from the OMAP PM
+interface into the Linux PM QoS code.
+
+Drivers need to express PM parameters which:
+
+- support the range of power management parameters present in the TI SRF;
+
+- separate the drivers from the underlying PM parameter
+  implementation, whether it is the TI SRF or Linux PM QoS or Linux
+  latency framework or something else;
+
+- specify PM parameters in terms of fundamental units, such as
+  latency and throughput, rather than units which are specific to OMAP
+  or to particular OMAP variants;
+
+- allow drivers which are shared with other architectures (e.g.,
+  DaVinci) to add these constraints in a way which won't affect non-OMAP
+  systems,
+
+- can be implemented immediately with minimal disruption of other
+  architectures.
+
+
+This document proposes the OMAP PM interface, including the following
+five power management functions for driver code:
+
+1. Set the maximum MPU wakeup latency:
+   (*pdata->set_max_mpu_wakeup_lat)(struct device *dev, unsigned long t)
+
+2. Set the maximum device wakeup latency:
+   (*pdata->set_max_dev_wakeup_lat)(struct device *dev, unsigned long t)
+
+3. Set the maximum system DMA transfer start latency (CORE pwrdm):
+   (*pdata->set_max_sdma_lat)(struct device *dev, long t)
+
+4. Set the minimum bus throughput needed by a device:
+   (*pdata->set_min_bus_tput)(struct device *dev, u8 agent_id, unsigned long r)
+
+5. Return the number of times the device has lost context
+   (*pdata->get_dev_context_loss_count)(struct device *dev)
+
+
+Further documentation for all OMAP PM interface functions can be
+found in arch/arm/plat-omap/include/mach/omap-pm.h.
+
+
+The OMAP PM layer is intended to be temporary
+---------------------------------------------
+
+The intention is that eventually the Linux PM QoS layer should support
+the range of power management features present in OMAP3.  As this
+happens, existing drivers using the OMAP PM interface can be modified
+to use the Linux PM QoS code; and the OMAP PM interface can disappear.
+
+
+Driver usage of the OMAP PM functions
+-------------------------------------
+
+As the 'pdata' in the above examples indicates, these functions are
+exposed to drivers through function pointers in driver .platform_data
+structures.  The function pointers are initialized by the board-*.c
+files to point to the corresponding OMAP PM functions:
+.set_max_dev_wakeup_lat will point to
+omap_pm_set_max_dev_wakeup_lat(), etc.  Other architectures which do
+not support these functions should leave these function pointers set
+to NULL.  Drivers should use the following idiom:
+
+        if (pdata->set_max_dev_wakeup_lat)
+            (*pdata->set_max_dev_wakeup_lat)(dev, t);
+
+The most common usage of these functions will probably be to specify
+the maximum time from when an interrupt occurs, to when the device
+becomes accessible.  To accomplish this, driver writers should use the
+set_max_mpu_wakeup_lat() function to to constrain the MPU wakeup
+latency, and the set_max_dev_wakeup_lat() function to constrain the
+device wakeup latency (from clk_enable() to accessibility).  For
+example,
+
+        /* Limit MPU wakeup latency */
+        if (pdata->set_max_mpu_wakeup_lat)
+            (*pdata->set_max_mpu_wakeup_lat)(dev, tc);
+
+        /* Limit device powerdomain wakeup latency */
+        if (pdata->set_max_dev_wakeup_lat)
+            (*pdata->set_max_dev_wakeup_lat)(dev, td);
+
+        /* total wakeup latency in this example: (tc + td) */
+
+The PM parameters can be overwritten by calling the function again
+with the new value.  The settings can be removed by calling the
+function with a t argument of -1 (except in the case of
+set_max_bus_tput(), which should be called with an r argument of 0).
+
+The fifth function above, omap_pm_get_dev_context_loss_count(),
+is intended as an optimization to allow drivers to determine whether the
+device has lost its internal context.  If context has been lost, the
+driver must restore its internal context before proceeding.
+
+
+Other specialized interface functions
+-------------------------------------
+
+The five functions listed above are intended to be usable by any
+device driver.  DSPBridge and CPUFreq have a few special requirements.
+DSPBridge expresses target DSP performance levels in terms of OPP IDs.
+CPUFreq expresses target MPU performance levels in terms of MPU
+frequency.  The OMAP PM interface contains functions for these
+specialized cases to convert that input information (OPPs/MPU
+frequency) into the form that the underlying power management
+implementation needs:
+
+6. (*pdata->dsp_get_opp_table)(void)
+
+7. (*pdata->dsp_set_min_opp)(u8 opp_id)
+
+8. (*pdata->dsp_get_opp)(void)
+
+9. (*pdata->cpu_get_freq_table)(void)
+
+10. (*pdata->cpu_set_freq)(unsigned long f)
+
+11. (*pdata->cpu_get_freq)(void)