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  1. 14 6月, 2012 4 次提交
    • J
      ARM: OMAP: Add DMTIMER capability variable to represent timer features · d1c1691b
      由 Jon Hunter 提交于 
      Although the OMAP timers share a common hardware design, there are some
differences between the timer instances in a given device. For example, a timer
maybe in a power domain that can be powered-of, so can lose its logic state and
need restoring where as another may be in power domain that is always be on.
Another example, is a timer may support different clock sources to drive the
timer. This information is passed to the dmtimer via the following platform data
structure.

struct dmtimer_platform_data {
	int (*set_timer_src)(struct platform_device *pdev, int source);
	int timer_ip_version;
	u32 needs_manual_reset:1;
	bool loses_context;
	int (*get_context_loss_count)(struct device *dev);
};

The above structure uses multiple variables to represent the timer features.
HWMOD also stores the timer capabilities using a bit-mask that represents the
features supported. By using the same format for representing the timer
features in the platform data as used by HWMOD, we can ...

1. Use the flags defined in the plat/dmtimer.h to represent the features
   supported.
2. For devices using HWMOD, we can retrieve the features supported from HWMOD.
3. Eventually, simplify the platform data structure to be ...

struct dmtimer_platform_data {
	int (*set_timer_src)(struct platform_device *pdev, int source);
	u32 timer_capability;
}

Another benefit from doing this, is that it will simplify the migration of the
dmtimer driver to device-tree. For example, in the current OMAP2+ timer code the
"loses_context" variable is configured at runtime by calling an architecture
specific function. For device tree this creates a problem, because we would need
to call the architecture specific function from within the dmtimer driver.
However, such attributes do not need to be queried at runtime and we can look up
the attributes via HWMOD or device-tree.

This changes a new "capability" variable to the platform data and timer
structure so we can start removing and simplifying the platform data structure.
Signed-off-by: NJon Hunter <jon-hunter@ti.com>
Signed-off-by: NTony Lindgren <tony@atomide.com>
      d1c1691b
    • J
      ARM: OMAP2+: Add dmtimer platform function to reserve systimers · b7b4ff76
      由 Jon Hunter 提交于 
      During early boot, one or two dmtimers are reserved by the kernel as system
timers (for clocksource and clockevents). These timers are marked as reserved
and the dmtimer driver is notified which timers have been reserved via the
platform data information.

For OMAP2+ devices the timers reserved may vary depending on device and compile
flags. Therefore, it is not easy to assume which timers we be reserved for the
system timers. In order to migrate the dmtimer driver to support device-tree we
need a way to pass the timers reserved for system timers to the dmtimer driver.
Using the platform data structure will not work in the same way as it is
currently used because the platform data structure will be stored statically in
the dmtimer itself and the platform data will be selected via the device-tree
match device function (of_match_device).

There are a couple ways to workaround this. One option is to store the system
timers reserved for the kernel in the device-tree and query them on boot.
The downside of this approach is that it adds some delay to parse the DT blob
to search for the system timers. Secondly, for OMAP3 devices we have a
dependency on compile time flags and the device-tree would not be aware of that
kernel compile flags and so we would need to address that.

The second option is to add a function to the dmtimer code to reserved the
system timers during boot and so the dmtimer knows exactly which timers are
being used for system timers. This also allows us to remove the "reserved"
member from the timer platform data. This seemed like the simpler approach and
so was implemented here.
Signed-off-by: NJon Hunter <jon-hunter@ti.com>
Signed-off-by: NTony Lindgren <tony@atomide.com>
      b7b4ff76
    • J
      ARM: OMAP2+: Remove unused max number of timers definition · 26fe4e45
      由 Jon Hunter 提交于 
      The OMAP2+ timer code has a definition for the maximum number of timers that
OMAP2+ devices have. This defintion is not used anywhere in the code and
appears to be left over. Furthermore the definition is not accurate for OMAP4
devices that only have 11 timers available because the 12th timer is reserved
as a secure timer and for OMAP3 devices the 12th timer is not available on
secure devices. Therefore, remove this definition.
Signed-off-by: NJon Hunter <jon-hunter@ti.com>
Signed-off-by: NTony Lindgren <tony@atomide.com>
      26fe4e45
    • J
      ARM: OMAP: Remove unnecessary clk structure · b8fd7331
      由 Jon Hunter 提交于 
      In the plat/dmtimer.h there is a structure named "clk" declared. This structure
is not used and appears to be left over from previous code. Hence, remove this
unused structure.

Verified that both omap1 and omap2plus kernel configurations build with this
change.
Signed-off-by: NJon Hunter <jon-hunter@ti.com>
Signed-off-by: NTony Lindgren <tony@atomide.com>
      b8fd7331
  3. 08 6月, 2012 6 次提交
  5. 06 6月, 2012 19 次提交
  7. 05 6月, 2012 4 次提交
  9. 04 6月, 2012 1 次提交
  11. 02 6月, 2012 6 次提交