This implements the remainder of:
OMAP clock: move rate recalc, propagation code up to plat-omap/clock.c
from Paul Walmsley which is not covered by the previous:
[ARM] omap: move clock propagation into core omap clock code
[ARM] omap: remove unnecessary calls to propagate_rate()
[ARM] omap: move propagate_rate() calls into generic omap clock code
commits.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Use the standard clk_set_rate() function in omap2_clk_arch_init()
rather than omap2_select_table_rate() -- this will ensure that clock
rates are recalculated and propagated correctly after those operations
are consolidated into clk_set_rate().
linux-omap source commit is 03c03330017eeb445b01957608ff5db49a7151b6.
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Current implementation will disable clocks in the order defined in clock34xx.h,
at least DPLL4_M2X2 will hang in certain cases (and prevent retention / off)
if clocks are not disabled in correct order. This patch makes sure the parent
clocks will be active when disabling a clock.
linux-omap source commit is 672680063420ef8c8c4e7271984bb9cc08171d29.
Signed-off-by: Tero Kristo <tero.kristo@nokia.com>
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Add the omap3_core_dpll_m2_set_rate() function to the OMAP3 clock code,
which calls into the SRAM function omap3_sram_configure_core_dpll() to
change the CORE DPLL M2 divider. (SRAM code is necessary since rate changes
on clocks upstream from the SDRC can glitch SDRAM accesses.)
Use this function for the set_rate function pointer in the dpll3_m2_ck
struct clk. With this function in place, PM/OPP code should be able to
alter SDRAM speed via code similar to:
clk_set_rate(&dpll3_m2_ck, target_rate).
linux-omap source commit is 7f8b2b0f4fe52238c67d79dedcd2794dcef4dddd.
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
For a given SDRAM clock rate, SDRAM chips require memory controllers
to use a specific set of timing minimums and maximums to transfer data
reliably. These parameters can be different for different memory chips
and can also potentially vary by board.
This patch adds the infrastructure for board-*.c files to pass this
timing data to the SDRAM controller init function. The timing data is
specified in an 'omap_sdrc_params' structure, in terms of SDRC
controller register values. An array of these structs, one per SDRC
target clock rate, is passed by the board-*.c file to
omap2_init_common_hw().
This patch does not define the values for different memory chips, nor
does it use the values for anything; those will come in subsequent patches.
linux-omap source commit is bc84ecfc795c2d1c5cda8da4127cf972f488a696.
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Separate SDRC code common to OMAP2/3 from mach-omap2/sdrc2xxx.c to
mach-omap2/sdrc.c. Rename the OMAP2xxx-specific functions to use an
'omap2xxx' prefix rather than an 'omap2' prefix, and use "sdrc" in the
function names rather than "memory." Mark several functions
as static that should not be used outside the sdrc2xxx.c file.
linux-omap source commit is bf1612b9d8d29379558500cd5de9ae0367c41fc4.
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Rename arch/arm/mach-omap2/memory.c to arch/arm/mach-omap2/sdrc2xxx.c, since
it contains exclusively SDRAM-related functions. Most of the functions
are also OMAP2xxx-specific - those which are common will be separated out
in a following patch.
linux-omap source commit is fe212f797e2efef9dc88bcb5db7cf9db3f9f562e.
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Move the contents of the arch/arm/mach-omap2/memory.h file to the
existing mach/sdrc.h file, and remove memory.h. Modify files which
include memory.h to include asm/arch/sdrc.h instead.
linux-omap source commit is e7ae2d89921372fc4b9712a32cc401d645597807.
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This fixes booting, and is a step toward fixing things properly:
- Make enable_reg u32 instead of u16
[rmk: virtual addresses are void __iomem *, not u32]
- Get rid of VIRTUAL_IO_ADDRESS for clocks
- Use __raw_read/write instead of omap_read/write for clock registers
This patch adds a bunch of compile warnings until omap1 clock
also uses offsets.
linux-omap source commit is 9d1dff8638c9e96a401e1885f9948662e9ff9636.
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This patch fixes a few OMAP2xxx CM_IDLEST bits that were incorrectly
marked as being OMAP2xxx-wide, when they were actually 2420-specific.
Also, originally when the PRCM register macros were defined, bit shift
macros used a "_SHIFT" suffix, and mask macros used none. This became
a source of bugs and confusion, as the mask macros were mistakenly
used for shift values. Gradually, the mask macros have been updated,
piece by piece, to add a "_MASK" suffix on the end to clarify. This
patch applies this change to the CM_IDLEST_* register bits.
The patch also adds a few bits that were missing, mostly from the 3430ES1
to ES2 revisions.
linux-omap source commits are d18eff5b5fa15e170794397a6a94486d1f774f77,
e1f1a5cc24615fb790cc763c96d1c5cfe6296f5b, and part of
9fe6b6cf8d9e0cbb429fd64553a4b3160a9e99e1
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Jouni Hogander <jouni.hogander@nokia.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This patch rolls up several cleanup patches.
1. Some unnecessarily verbose variable names are used in several clock.c
functions; clean these up per CodingStyle.
2. Remove omap2_get_clksel() and just use clk->clksel_reg and
clk->clksel_mask directly.
3. Get rid of void __iomem * usage in omap2_clksel_get_src_field.
Prepend the function name with an underscore to highlight that it is a
static function.
linux-omap source commits are 7fa95e007ea2f3c4d0ecd2779d809756e7775894,
af0ea23f1ee4a5bea3b026e38761b47089f9048a, and
91c0c979b47c44b08f80e4f8d4c990fb158d82c4.
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
During _omap3_noncore_dpll_lock(), if a DPLL has no active downstream
clocks and DPLL autoidle is enabled, the DPLL may never lock, since it
will enter autoidle immediately. To resolve this, disable DPLL
autoidle while locking the DPLL, and unconditionally wait for the DPLL
to lock. This fixes some bugs where the kernel would hang when returning
from retention or return the wrong rate for the DPLL.
This patch is a collaboration with Peter de Schrijver
<peter.de-schrijver@nokia.com> and Kevin Hilman
<khilman@deeprootsystems.com>.
linux-omap source commit is 3b7de4be879f1f4f55ae59882a5cbd80f6dcf0f0.
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Cc: Peter de Schrijver <peter.de-schrijver@nokia.com>
Cc: Kevin Hilman <khilman@deeprootsystems.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The DPLL FREQSEL jitter correction bits are set based on a table in
the 34xx TRM, Table 4-38, according to the DPLL's internal clock
frequency "Fint." Several Fint frequency ranges are missing from this
table. Previously, we allowed these Fint frequency ranges to be
selected in the rate rounding code, but did not change the FREQSEL bits.
Correspondence with the OMAP hardware team indicates that Fint values
not in the table should not be used. So, prevent them from being
selected during DPLL rate rounding. This removes warnings and also
can prevent the chip from locking up.
The first pass through the rate rounding code will update the DPLL max
and min dividers appropriately, so later rate rounding passes will run
faster than the first.
Peter de Schrijver <peter.de-schrijver@nokia.com> put up with several
test cycles of this patch - thanks Peter.
linux-omap source commit is f9c1b82f55b60fc39eaa6e7aa1fbe380c0ffe2e9.
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Cc: Peter de Schrijver <peter.de-schrijver@nokia.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The previous DPLL rate rounding algorithm counted the divider (N) down
from the maximum to 1. Since we currently use a broad DPLL rate
tolerance, and lower N values are more power-efficient, we can often
bypass several iterations through the loop by counting N upwards from
1.
Peter de Schrijver <peter.de-schrijver@nokia.com> put up with several
test cycles of this patch - thanks Peter.
linux-omap source commit is 6f6d82bb2f80fa20a841ac3e95a6f44a5a156188.
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Cc: Peter de Schrijver <peter.de-schrijver@nokia.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Remove some clutter from omap2_dpll_round_rate().
linux-omap source commit is 4625dceb8583c02a6d67ededc9f6a8347b6b8cb7.
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Convert struct dpll_data.idlest_bit field to idlest_mask. Needed since
OMAP2 uses two bits for DPLL IDLEST rather than one.
While here, add the missing idlest_* fields for DPLL3.
linux-omap source commits are 25bab0f176b0a97be18a1b38153f266c3a155784
and b0f7fd17db2aaf8e6e9a2732ae3f4de0874db01c.
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
OMAP34xx ES2 TRM Delta G to H states that the divider for DPLL1_FCLK and
DPLL2_FCLK can divide by 4 in addition to dividing by 1 and 2. Encode this
into the OMAP3 clock framework.
linux-omap source commit is 050684c18f2ea0b08fdd5233a0cd3c7f96e00a0e.
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Fix DPLL jitter correction programming. Previously,
omap3_noncore_dpll_program() stored the FREQSEL jitter correction
parameter to the wrong register. This caused jitter correction to be set
incorrectly and also caused the DPLL divider to be programmed incorrectly.
Also, fix DPLL divider programming. An off-by-one error existed in
omap3_noncore_dpll_program(), causing DPLLs to be programmed with a higher
divider than intended.
linux-omap source commit is 5c0ec88a2145cdf2f2c9cc5fae49635c4c2476c7.
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Using sdti doesn't keep emu_pwrdm on if hardware supervised pwrdm
transitions are used. This causes sdti stop to work when power
management is initialized and hardware supervised pwrdm control is
enabled. This patch disables hardware supervised pwrdm control for
emu_pwrdm. Now emu_pwrdm is switched off on boot by software when it
is not used.
Signed-off-by: Jouni Hogander <jouni.hogander@nokia.com>
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Fix the clockdomain autodep code to respect omap_chip platform flags.
Resolves "Unable to handle kernel paging request at virtual address
5f75706d" panic during power management initialization on OMAP2.
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Enabling clock in a disabled power domain causes the power domain to be
turned on. However, the power transition is not always finished when
clk_enable() returns and this randomly crashes the kernel when an
interrupt happens right after the clk_enable, and the kernel tries to
read the irq status register for that domain.
Why the irq status register is inaccessible, I don't know. Also it
doesn't seem to be related to the module being not powered up, but to
the transition itself.
The same could perhaps happen after clk_disable also, but I have not
witnessed that.
The problem affects at least dss, cam and sgx clocks.
This change waits for the transition to be finished before returning
from omap2_clkdm_clk_enable().
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@nokia.com>
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The SGX device on OMAP3 does not support retention, so remove RET from the
list of possible SGX power states. Problem debugged by Richard Woodruff
<r-woodruff2@ti.com>.
Signed-off-by: Richard Woodruff <r-woodruff2@ti.com>
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Each DPLL exists in its own powerdomain (cf 34xx TRM figure 4-18) and
clockdomain; so, create powerdomain and clockdomain structures for them.
Mark each DPLL clock as belonging to their respective DPLL clockdomain.
cf. 34xx TRM Table 4-27 (among other references).
linux-omap source commits are acdb615850b9b4f7d1ab68133a16be8c8c0e7419 and
a8798a48f33e9268dcc7f30a4b4a3ce4220fe0c9.
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
sys_clkout2 belongs in the core_clkdm (3430 TRM section 4.7.2.2).
It's not clear whether it actually is in the CORE clockdomain, or whether
it is technically in a different clockdomain; but this is closer to
reality than the present configuration.
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Add clockdomains for the CM and PRM. These will ultimately replace the
"wkup_clkdm", which appears to not actually exist on the hardware.
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
struct clockdomain contains a struct powerdomain *pwrdm and const char
*pwrdm_name. The pwrdm_name is only used at initialization to look up
the appropriate pwrdm pointer. Combining these into a union saves
about 100 bytes on 3430SDP. This patch should not cause any change in
kernel function.
Updated to gracefully handle autodeps that contain invalid powerdomains,
per Russell King's review comments.
Boot-tested on BeagleBoard ES2.1.
linux-omap source commit is 718fc6cd4db902aa2242a736cc3feb8744a4c71a.
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This patch adds a CPUfreq frequency-table implementation for OMAP2 by
walking the PRCM rate-table for available entries and adding them to a
CPUfreq table.
CPUfreq can then be used to manage switching between all the available
entries in the PRCM rate table. Either use the CPUfreq sysfs
interface directly, (see Section 3 of Documentation/cpu-freq/user-guide.txt)
or use the cpufrequtils package:
http://www.kernel.org/pub/linux/utils/kernel/cpufreq/cpufrequtils.html
Signed-off-by: Kevin Hilman <khilman@mvista.com>
Updated to try to use cpufreq_table if it exists.
linux-omap source commit is 77ce544fa48deb7a2003f454624e3ca10d37ab87.
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Filling the set_rate and round_rate fields of dpll4_m4_ck makes
this clock programmable through clk_set_rate(). This is needed
to give omapfb control over the dss1_alwon_fck rate.
This patch includes a fix from Tomi Valkeinen <tomi.valkeinen@nokia.com>.
linux-omap source commits are e42218d45afbc3e654e289e021e6b80c657b16c2 and
9d211b761b3cdf7736602ecf7e68f8a298c13278.
Signed-off-by: Måns Rullgård <mans@mansr.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@nokia.com>
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Add CSI2 clock struct for handling it with clock API when TI PM is disabled.
linux-omap source commit is 8b20f4498928459276bd3366e3381ad595d23432.
Signed-off-by: Sergio Aguirre <saaguirre@ti.com>
Acked-by: Paul Walmsley <paul@pwsan.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The GFX/SGX functional and interface clocks have different masks, for
some unknown reason, so split EN_SGX_SHIFT into one each for fclk and
iclk.
Correct according to the TRM and the far more important 'does this
actually work at all?' metric.
linux-omap source commit is de1121fdb899f762b9e717f44eaf3fae7c00cd3e.
Signed-off-by: Daniel Stone <daniel.stone@nokia.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Fix some bugs in the OMAP3 clock tree pertaining to the 96MHz clocks.
The 96MHz portion of the clock tree should now have reasonable
fidelity to the 34xx TRM Rev I.
One remaining question mark: it's not clear exactly which 96MHz source
clock the USIM uses. This patch sticks with the previous setting, which
seems reasonable.
linux-omap source commit is 15c706e8179ce238c3ba70a25846a36b73bd2359.
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Remove usbhost_sar_fclk from the OMAP3 clock framework. The bit that
the clock was tweaking doesn't actually enable or disable a clock; it
controls whether the hardware will save and restore USBHOST state
when the powerdomain changes state. (That happens to coincidentally
enable a clock for the duration of the operation, hence the earlier
confusion.)
In place of the clock, mark the USBHOST powerdomain as supporting
hardware save-and-restore functionality.
linux-omap source commit is f3ceac86a9d425d101d606d87a5af44afef27179.
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This patch adds a missing OMAP24xx clock, the SSI L4 interface clock,
as "ssi_l4_ick".
linux-omap source commit is ace129d39b3107d330d4cf6934385d13521f2fec.
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Fix sparse & checkpatch warnings in OMAP2/3 PRCM & PM code. This mostly
consists of:
- converting pointer comparisons to integers in form similar to
(ptr == 0) to the standard idiom (!ptr)
- labeling a few non-static private functions as static
- adding prototypes for *_init() functions in the appropriate header
files, and getting rid of the corresponding open-coded extern
prototypes in other C files
- renaming the variable 'sclk' in mach-omap2/clock.c:omap2_get_apll_clkin
to avoid shadowing an earlier declaration
Clean up checkpatch issues. This mostly involves:
- converting some asm/ includes to linux/ includes
- cleaning up some whitespace
- getting rid of braces for conditionals with single following statements
Also take care of a few odds and ends, including:
- getting rid of unlikely() and likely() - none of this code is particularly
fast-path code, so the performance impact seems slim; and some of those
likely() and unlikely() indicators are probably not as accurate as the
ARM's branch predictor
- removing some superfluous casts
linux-omap source commit is 347df59f5d20fdf905afbc26b1328b0e28a8a01b.
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Add non-CORE DPLL rate set code and M,N programming for OMAP3.
Connect it to OMAP34xx DPLLs 1, 2, 4, 5 via the clock framework.
You may see some warnings on rate sets from the freqsel code. The
table that TI presented in the 3430 TRM Rev F does not cover Fint <
750000, which definitely occurs in practice. However, the lack of this
freqsel case does not appear to impair the DPLL rate change.
linux-omap source commit is 689fe67c6d1ad8f52f7f7b139a3274b79bf3e784.
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
... which now means no driver requests the "armxor_ck" clock directly.
Also, fix the error handling for clk_get(), ensuring that we propagate
the error returned from clk_get().
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
By providing a dummy ick for OMAP1510 and OMAP310, we avoid having
SoC conditional clock information in i2c-omap.c. Also, fix the
error handling by making sure we propagate the error returned via
clk_get().
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Rather than introducing a special 'mcbsp_clk' with code behind it in
mach-omap*/mcbsp.c to handle the SoC specifics, arrange for the mcbsp
driver to be like any other driver. mcbsp requests its fck and ick
clocks directly, and the SoC specific code deals with selecting the
correct clock.
There is one oddity to deal with - OMAP1 fiddles with the DSP clocks
and DSP reset, so we move this to the two callback functions.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Convert OMAP MMC driver to match clocks using the device ID and a
connection ID rather than a clock name. This allows us to eliminate
the OMAP1/OMAP2 differences for the function clock.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
By providing a dummy clock node, we can eliminate the SoC conditional
clock handing in the OMAP drivers, moving this knowledge out of the
driver and into the machine clock support code.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Russell King