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author | Yunhong Jiang <yunhong.jiang@intel.com> | 2015-08-04 12:17:53 -0700 |
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committer | Yunhong Jiang <yunhong.jiang@intel.com> | 2015-08-04 15:44:42 -0700 |
commit | 9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch) | |
tree | 1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/Documentation/memory-devices | |
parent | 98260f3884f4a202f9ca5eabed40b1354c489b29 (diff) |
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base.
It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and
the base is:
commit 0917f823c59692d751951bf5ea699a2d1e2f26a2
Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date: Sat Jul 25 12:13:34 2015 +0200
Prepare v4.1.3-rt3
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
We lose all the git history this way and it's not good. We
should apply another opnfv project repo in future.
Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423
Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Diffstat (limited to 'kernel/Documentation/memory-devices')
-rw-r--r-- | kernel/Documentation/memory-devices/ti-emif.txt | 57 |
1 files changed, 57 insertions, 0 deletions
diff --git a/kernel/Documentation/memory-devices/ti-emif.txt b/kernel/Documentation/memory-devices/ti-emif.txt new file mode 100644 index 000000000..f4ad9a7d0 --- /dev/null +++ b/kernel/Documentation/memory-devices/ti-emif.txt @@ -0,0 +1,57 @@ +TI EMIF SDRAM Controller Driver: + +Author +======== +Aneesh V <aneesh@ti.com> + +Location +============ +driver/memory/emif.c + +Supported SoCs: +=================== +TI OMAP44xx +TI OMAP54xx + +Menuconfig option: +========================== +Device Drivers + Memory devices + Texas Instruments EMIF driver + +Description +=========== +This driver is for the EMIF module available in Texas Instruments +SoCs. EMIF is an SDRAM controller that, based on its revision, +supports one or more of DDR2, DDR3, and LPDDR2 SDRAM protocols. +This driver takes care of only LPDDR2 memories presently. The +functions of the driver includes re-configuring AC timing +parameters and other settings during frequency, voltage and +temperature changes + +Platform Data (see include/linux/platform_data/emif_plat.h): +===================================================================== +DDR device details and other board dependent and SoC dependent +information can be passed through platform data (struct emif_platform_data) +- DDR device details: 'struct ddr_device_info' +- Device AC timings: 'struct lpddr2_timings' and 'struct lpddr2_min_tck' +- Custom configurations: customizable policy options through + 'struct emif_custom_configs' +- IP revision +- PHY type + +Interface to the external world: +================================ +EMIF driver registers notifiers for voltage and frequency changes +affecting EMIF and takes appropriate actions when these are invoked. +- freq_pre_notify_handling() +- freq_post_notify_handling() +- volt_notify_handling() + +Debugfs +======== +The driver creates two debugfs entries per device. +- regcache_dump : dump of register values calculated and saved for all + frequencies used so far. +- mr4 : last polled value of MR4 register in the LPDDR2 device. MR4 + indicates the current temperature level of the device. |