Adds a function to read the various GPMC chip-select settings from
device-tree and store them in the gpmc_settings structure.
Update the GPMC device-tree binding documentation to describe these
options.
Signed-off-by: Jon Hunter <jon-hunter@ti.com>
Tested-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
With the addition of the gpmc_cs_program_settings(), we no longer need
or use gpmc_cs_configure() to configure some of the GPMC chip-select
options. So rename the function to gpmc_configure() and remove code that
modifies options in the CONFIG1 register.
Signed-off-by: Jon Hunter <jon-hunter@ti.com>
Tested-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
The GPMC has various different configuration options such as bus-width,
synchronous or asychronous mode selection, burst mode options etc.
Currently, there is no common function for configuring these options and
various devices set these options by either programming the GPMC CONFIG1
register directly or by calling gpmc_cs_configure() to set some of the
options.
Add a new function for configuring all of the GPMC options. Having a common
function for configuring this options will simplify code and ease the
migration to device-tree.
Also add a new capability flag to detect devices that support the
address-address-data multiplexing mode.
Signed-off-by: Jon Hunter <jon-hunter@ti.com>
Tested-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
The GPMC has various different configuration options such as bus-width,
synchronous or asychronous mode selection, burst mode options etc.
Currently, there is no central structure for storing all these options
when configuring the GPMC for a given device. Some of the options are
stored in the GPMC timing structure and some are directly programmed
into the GPMC configuration register. Add a new structure to store
these options and convert code to use this structure. Adding this
structure will allow us to create a common function for configuring
these options.
Signed-off-by: Jon Hunter <jon-hunter@ti.com>
Tested-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
This patch marks a bunch of functions that are local
to gpmc.c file only as static.
Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Reviewed-by: Jon Hunter <jon-hunter@ti.com>
Signed-off-by: Jon Hunter <jon-hunter@ti.com>
When setting the GPMC device type, make sure any previous
bits are cleared down, before applying the new setting.
For OMAP4+ devices MUXADDDATA is a 2-bit field (bits 9:8)
where as for OMAP2/3 devices it was only a one bit field
(bit 9). For OMAP2/3 devices bit 8 is reserved and the
OMAP documentation says to write a 0 to this bit. So
clearing bit 8 on OMAP2/3 devices should not be a problem.
Hence update the code to handle both bits 8 and 9 for all
devices.
Signed-off-by: Mark Jackson <mpfj@newflow.co.uk>
[jon-hunter@ti.com: updated changelog]
Signed-off-by: Jon Hunter <jon-hunter@ti.com>
Presently there are three peripherals that gets it timing
by runtime calculation. Those peripherals can work with
frequency scaling that affects gpmc clock. But timing
calculation for them are in different ways.
Here a generic runtime calculation method is proposed. Input
to this function were selected so that they represent timing
variables that are present in peripheral datasheets. Motive
behind this was to achieve DT bindings for the inputs as is.
Even though a few of the tusb6010 timings could not be made
directly related to timings normally found on peripherals,
expressions used were translated to those that could be
justified.
There are possibilities of improving the calculations, like
calculating timing for read & write operations in a more
similar way. Expressions derived here were tested for async
onenand on omap3evm (as vanilla Kernel does not have omap3evm
onenand support, local patch was used). Other peripherals,
tusb6010, smc91x calculations were validated by simulating
on omap3evm.
Regarding "we_on" for onenand async, it was found that even
for muxed address/data, it need not be greater than
"adv_wr_off", but rather could be derived from write setup
time for peripheral from start of access time, hence would
more be in line with peripheral timings. With this method
it was working fine. If it is required in some cases to
have "we_on" same as "wr_data_mux_bus" (i.e. greater than
"adv_wr_off"), another variable could be added to indicate
it. But such a requirement is not expected though.
It has been observed that "adv_rd_off" & "adv_wr_off" are
currently calculated by adding an offset over "oe_on" and
"we_on" respectively in the case of smc91x. But peripheral
datasheet does not specify so and so "adv_rd(wr)_off" has
been derived (to be specific, made ignorant of "oe_on" and
"we_on") observing datasheet rather than adding an offset.
Hence this generic routine is expected to work for smc91x
(91C96 RX51 board). This was verified on smsc911x (9220 on
OMAP3EVM) - a similar ethernet controller.
Timings are calculated in ps to prevent rounding errors and
converted to ns at final stage so that these values can be
directly fed to gpmc_cs_set_timings(). gpmc_cs_set_timings()
would be modified to take ps once all custom timing routines
are replaced by the generic routine, at the same time
generic timing routine would be modified to provide timings
in ps. struct gpmc_timings field types are upgraded from
u16 => u32 so that it can hold ps values.
Whole of this exercise is being done to achieve driver and
DT conversion. If timings could not be calculated in a
peripheral agnostic way, either gpmc driver would have to
be peripheral gnostic or a wrapper arrangement over gpmc
driver would be required.
Signed-off-by: Afzal Mohammed <afzal@ti.com>
Configure busturnaround, cycle2cycledelay, waitmonitoringtime,
clkactivationtime in gpmc_cs_set_timings(). This is done so
that boards can configure these parameters of gpmc in Kernel
instead of relying on bootloader. Also configure bool type
timings like extradelay.
This needed change to the existing users that were configuring
clk activation time and extra delay by directly writing to
registers. Thanks to Tony for making me aware of users of clk
activation and being kind enough to test the modified one.
Signed-off-by: Afzal Mohammed <afzal@ti.com>
Requirement of gpmc header outside of mach-omap2 has been
cutoff, move gpmc header file in plat-omap folder to local
mach-omap2 folder
Objective - common zImage participation of omap
Signed-off-by: Afzal Mohammed <afzal@ti.com>
Jon Hunter