Commit Graph

7 Commits

Author SHA1 Message Date
Axel Lin
e5445ee6a6 memory: emif: Add ifdef CONFIG_DEBUG_FS guard for emif_debugfs_[init|exit]
Add ifdef CONFIG_DEBUG_FS guard for emif_debugfs_[init|exit], and adds stub
functions for the case CONFIG_DEBUG_FS is not set.

When CONFIG_DEBUG_FS is enabled, debugfs_create_dir and debugfs_create_file
return NULL on failure, fix it.

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Acked-by : Santosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-09-26 13:56:03 -07:00
Aneesh V
e6b42eb6a6 memory: emif: add device tree support to emif driver
Device tree support for the EMIF driver. LPDDR2 generic timings
extraction from device is managed using couple of helper
functions which can be used by other memory controller
drivers.

Reviewed-by: Benoit Cousson <b-cousson@ti.com>
Reviewed-by: Grant Likely <grant.likely@secretlab.ca>
Tested-by: Lokesh Vutla <lokeshvutla@ti.com>
Signed-off-by: Aneesh V <aneesh@ti.com>
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-09-04 16:14:31 -07:00
Aneesh V
aac10aaa8c memory: emif: add debugfs entries for emif
Add debug entries for:
	1. calculated registers per frequency
	2. last polled value of MR4(temperature level
	   of LPDDR2 memory)

Signed-off-by: Aneesh V <aneesh@ti.com>
Reviewed-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Reviewed-by: Benoit Cousson <b-cousson@ti.com>
[santosh.shilimkar@ti.com: Moved to drivers/memory from drivers/misc]
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Tested-by: Lokesh Vutla <lokeshvutla@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-05-02 11:00:08 -07:00
Aneesh V
98231c4fc3 memory: emif: add one-time settings
Add settings that are not dependent on frequency
or any other transient parameters. This includes
- power managment control init
- impedence calibration control
- frequency independent phy configuration registers
- initialization of temperature polling

Signed-off-by: Aneesh V <aneesh@ti.com>
Reviewed-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Reviewed-by: Benoit Cousson <b-cousson@ti.com>
[santosh.shilimkar@ti.com: Moved to drivers/memory from drivers/misc]
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Tested-by: Lokesh Vutla <lokeshvutla@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-05-02 10:58:12 -07:00
Aneesh V
68b4aee35d memory: emif: add interrupt and temperature handling
Add an ISR for EMIF that:
	1. reports details of access errors
	2. takes action on thermal events

Also clear all interrupts on shut-down. Pending IRQs
may casue problems during warm-reset.

Temperature handling:
EMIF can be configured to poll the temperature level
of an LPDDR2 device from the MR4 mode register in the
device. EMIF generates an interrupt whenever it identifies
a temperature level change between two consecutive pollings.

Some of the timing parameters need to be de-rated at high
temperatures. The interrupt handler takes care of doing
this and also takes care of going back to nominal settings
when temperature falls back to nominal levels.

Signed-off-by: Aneesh V <aneesh@ti.com>
Reviewed-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Reviewed-by: Benoit Cousson <b-cousson@ti.com>
[santosh.shilimkar@ti.com: Moved to drivers/memory from drivers/misc]
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-05-02 10:56:30 -07:00
Aneesh V
a93de288aa memory: emif: handle frequency and voltage change events
Change SDRAM timings and other settings as necessary
on voltage and frequency changes. We calculate these
register settings based on data from the device data
sheet and inputs such a frequency, voltage state(stable
or ramping), temperature level etc.

TODO: frequency and voltage change handling needs to
be integrated with clock framework and regulator
framework respectively. This is not done today
due to missing pieces in the kernel.

Signed-off-by: Aneesh V <aneesh@ti.com>
Reviewed-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Reviewed-by: Benoit Cousson <b-cousson@ti.com>
[santosh.shilimkar@ti.com: Moved to drivers/memory from drivers/misc]
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Tested-by: Lokesh Vutla <lokeshvutla@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-05-02 10:52:09 -07:00
Aneesh V
7ec944538d memory: emif: add basic infrastructure for EMIF driver
EMIF is an SDRAM controller used in various Texas Instruments
SoCs. EMIF supports, based on its revision, one or more of
LPDDR2/DDR2/DDR3 protocols.

Add the basic infrastructure for EMIF driver that includes
driver registration, probe, parsing of platform data etc.

Signed-off-by: Aneesh V <aneesh@ti.com>
Reviewed-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Reviewed-by: Benoit Cousson <b-cousson@ti.com>
[santosh.shilimkar@ti.com: Moved to drivers/memory from drivers/misc]
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Tested-by: Lokesh Vutla <lokeshvutla@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2012-05-02 00:10:49 -07:00