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authorYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 12:17:53 -0700
committerYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 15:44:42 -0700
commit9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch)
tree1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/Documentation/fmc/API.txt
parent98260f3884f4a202f9ca5eabed40b1354c489b29 (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>
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+Functions Exported by fmc.ko
+****************************
+
+The FMC core exports the usual 4 functions that are needed for a bus to
+work, and a few more:
+
+ int fmc_driver_register(struct fmc_driver *drv);
+ void fmc_driver_unregister(struct fmc_driver *drv);
+ int fmc_device_register(struct fmc_device *fmc);
+ void fmc_device_unregister(struct fmc_device *fmc);
+
+ int fmc_device_register_n(struct fmc_device **fmc, int n);
+ void fmc_device_unregister_n(struct fmc_device **fmc, int n);
+
+ uint32_t fmc_readl(struct fmc_device *fmc, int offset);
+ void fmc_writel(struct fmc_device *fmc, uint32_t val, int off);
+ void *fmc_get_drvdata(struct fmc_device *fmc);
+ void fmc_set_drvdata(struct fmc_device *fmc, void *data);
+
+ int fmc_reprogram(struct fmc_device *f, struct fmc_driver *d, char *gw,
+ int sdb_entry);
+
+The data structure that describe a device is detailed in *note FMC
+Device::, the one that describes a driver is detailed in *note FMC
+Driver::. Please note that structures of type fmc_device must be
+allocated by the caller, but must not be released after unregistering.
+The fmc-bus itself takes care of releasing the structure when their use
+count reaches zero - actually, the device model does that in lieu of us.
+
+The functions to register and unregister n devices are meant to be used
+by carriers that host more than one mezzanine. The devices must all be
+registered at the same time because if the FPGA is reprogrammed, all
+devices in the array are affected. Usually, the driver matching the
+first device will reprogram the FPGA, so other devices must know they
+are already driven by a reprogrammed FPGA.
+
+If a carrier hosts slots that are driven by different FPGA devices, it
+should register as a group only mezzanines that are driven by the same
+FPGA, for the reason outlined above.
+
+Finally, the fmc_reprogram function calls the reprogram method (see
+*note The API Offered by Carriers:: and also scans the memory area for
+an SDB tree. You can pass -1 as sdb_entry to disable such scan.
+Otherwise, the function fails if no tree is found at the specified
+entry point. The function is meant to factorize common code, and by
+the time you read this it is already used by the spec-sw and fine-delay
+modules.