Changeset 284 for branch/giet_vm_ioc_drivers/giet_drivers/ioc_driver.c

Timestamp:

Jan 31, 2014, 2:37:38 PM (10 years ago)

Author:

cfuguet

Message:

Modification of comments format on SPI-SDCARD driver to respect
GIET-VM format

File:

• branch/giet_vm_ioc_drivers/giet_drivers/ioc_driver.c (modified) (2 diffs)

branch/giet_vm_ioc_drivers/giet_drivers/ioc_driver.c

@@ -1 +1 @@
 ///////////////////////////////////////////////////////////////////////////////////
-// File     : ioc_driver.c
-// Date     : 23/05/2013
-// Author   : alain greiner
+// File       : ioc_driver.c
+// Date       : 23/05/2013
+// Author     : alain greiner
+// Maintainer : cesar fuguet
 // Copyright (c) UPMC-LIP6
 ///////////////////////////////////////////////////////////////////////////////////
@@ -12 +13 @@
 //
 // The _ioc_read() and _ioc_write() functions use the _ioc_access() function,
-// that is always blocking, but can be called in 4 modes:
-//
-// - In BOOT_PA mode, the _ioc_access() function use the buffer virtual address 
-//   as a physical address (as the page tables are not build) and use a polling
-//   policy on the IOC_STATUS register to detect transfer completion, as
-//   hardware interrupts are not activated. This mode is used by the
-//   boot code to load the map.bin file into memory.
+// that is always blocking. The _ioc_access function will call the read or
+// write function in the driver of the choosen IOC peripheral, which can be for
+// now: BDV, HBA and SPI. This function can be called in 4 modes:
+//
+// - In BOOT_PA mode, the _ioc_access() function use the buffer virtual address
+//   as a physical address (as the page tables are not build). This mode is
+//   used by the boot code to load the map.bin file into memory.
 //
 // - In BOOT_VA mode, the _ioc_access() function makes a V2P translation to
-//   compute the buffer physical address, and use a polling policy on IOC_STATUS
-//   register to detect transfer completion. This mode is used by the boot code
-//   to load the various .elf files into memory.
+//   compute the buffer physical address. This mode is used by the boot code to
+//   load the various .elf files into memory.
 //
 // - In KERNEL mode, the _ioc_access() function makes a V2P translation to
-//   compute the buffer physical address, and use a descheduling strategy:
-//   The ISR executed when transfer completes should restart the calling task. 
-//   There is no checking of user access right to the memory buffer.
-//   This mode must be used to access IOC, for an "open" system call.
+//   compute the buffer physical address. There is no checking of user access
+//   right to the memory buffer.  This mode must be used to access IOC, for an
+//   "open" system call.
 //
 // - In USER mode, the _ioc_access() function makes a V2P translation to
-//   compute the buffer physical address, and use a descheduling strategy:
-//   The ISR executed when transfer completes should restart the calling task, 
-//   The user access right to the memory buffer must be checked.
-//   This mode must be used to access IOC, for a "read/write" system call.
-//
-// As the IOC component can be used by several programs running in parallel,
-// the _ioc_lock variable guaranties exclusive access to the device.  The
-// _ioc_read() and _ioc_write() functions use atomic LL/SC to get the lock.
+//   compute the buffer physical address. The user access right to the memory
+//   buffer must be checked.  This mode must be used to access IOC, for a
+//   "read/write" system call.
 //
 // The IOMMU can be activated or not: