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diff --git a/doc/bsp_howto/rtc.t b/doc/bsp_howto/rtc.t deleted file mode 100644 index 796f2c9ce4..0000000000 --- a/doc/bsp_howto/rtc.t +++ /dev/null @@ -1,225 +0,0 @@ -@c -@c COPYRIGHT (c) 1988-2002. -@c On-Line Applications Research Corporation (OAR). -@c All rights reserved. - -@chapter Real-Time Clock Driver - -@section Introduction - -The Real-Time Clock (@b{RTC}) driver is responsible for providing an -interface to an @b{RTC} device. [NOTE: In this chapter, the abbreviation -@b{TOD} is used for @b{Time of Day}.] The capabilities provided by this -driver are: - -@itemize @bullet -@item Set the RTC TOD to RTEMS TOD -@item Set the RTEMS TOD to the RTC TOD -@item Get the RTC TOD -@item Set the RTC TOD to the Specified TOD -@item Get the Difference Between the RTEMS and RTC TOD -@end itemize - -The reference implementation for a real-time clock driver can -be found in @code{c/src/lib/libbsp/shared/tod.c}. This driver -is based on the libchip concept and can be easily configured -to work with any of the RTC chips supported by the RTC -chip drivers in the directory @code{c/src/lib/lib/libchip/rtc}. -There is a README file in this directory for each supported -RTC chip. Each of these README explains how to configure the -shared libchip implementation of the RTC driver for that particular -RTC chip. - -The DY-4 DMV177 BSP used the shared libchip implementation of the RTC -driver. There were no DMV177 specific configuration routines. A BSP -could use configuration routines to dynamically determine what type -of real-time clock is on a particular board. This would be useful for -a BSP supporting multiple board models. The relevant ports of -the DMV177's @code{RTC_Table} configuration table is below: - -@example - -#include <bsp.h> -#include <libchip/rtc.h> -#include <libchip/icm7170.h> - -bool dmv177_icm7170_probe(int minor); - -rtc_tbl RTC_Table[] = @{ - @{ "/dev/rtc0", /* sDeviceName */ - RTC_ICM7170, /* deviceType */ - &icm7170_fns, /* pDeviceFns */ - dmv177_icm7170_probe, /* deviceProbe */ - (void *) ICM7170_AT_1_MHZ, /* pDeviceParams */ - DMV170_RTC_ADDRESS, /* ulCtrlPort1 */ - 0, /* ulDataPort */ - icm7170_get_register_8, /* getRegister */ - icm7170_set_register_8, /* setRegister */ - @} -@}; - -unsigned long RTC_Count = (sizeof(RTC_Table)/sizeof(rtc_tbl)); -rtems_device_minor_number RTC_Minor; - -bool dmv177_icm7170_probe(int minor) -@{ - volatile unsigned16 *card_resource_reg; - - card_resource_reg = (volatile unsigned16 *) DMV170_CARD_RESORCE_REG; - - if ( (*card_resource_reg & DMV170_RTC_INST_MASK) == DMV170_RTC_INSTALLED ) - return TRUE; - return FALSE; -@} - -@end example - -@section Initialization - -The @code{rtc_initialize} routine is responsible for initializing the -RTC chip so it can be used. The shared libchip implementation of this -driver supports multiple RTCs and bases its initialization order on -the order the chips are defined in the @code{RTC_Table}. Each chip -defined in the table may or may not be present on this particular board. -It is the responsibility of the @code{deviceProbe} to indicate the -presence of a particular RTC chip. The first RTC found to be present -is considered the preferred RTC. - -In the shared libchip based implementation -of the driver, the following actions are performed: - -@example -@group -rtems_device_driver rtc_initialize( - rtems_device_major_number major, - rtems_device_minor_number minor_arg, - void *arg -) -@{ - for each RTC configured in RTC_Table - if the deviceProbe for this RTC indicates it is present - set RTC_Minor to this device - set RTC_Present to TRUE - break out of this loop - - if RTC_Present is not TRUE - return RTEMS_INVALID_NUMBER to indicate that no RTC is present - - register this minor number as the "/dev/rtc" - - perform the deviceInitialize routine for the preferred RTC chip - - for RTCs past this one in the RTC_Table - if the deviceProbe for this RTC indicates it is present - perform the deviceInitialize routine for this RTC chip - register the configured name for this RTC -@} -@end group -@end example - -The @code{deviceProbe} routine returns TRUE if the device -configured by this entry in the @code{RTC_Table} is present. -This configuration scheme allows one to support multiple versions -of the same board with a single BSP. For example, if the first -generation of a board had Vendor A's RTC chip and the second -generation had Vendor B's RTC chip, RTC_Table could contain -information for both. The @code{deviceProbe} configured -for Vendor A's RTC chip would need to return TRUE if the -board was a first generation one. The @code{deviceProbe} -routines are very board dependent and must be provided by -the BSP. - -@section setRealTimeToRTEMS - -The @code{setRealTimeToRTEMS} routine sets the current RTEMS TOD to that -of the preferred RTC. - -@example -@group -void setRealTimeToRTEMS(void) -@{ - if no RTCs are present - return - - invoke the deviceGetTime routine for the preferred RTC - set the RTEMS TOD using rtems_clock_set -@} -@end group -@end example - -@section setRealTimeFromRTEMS - -The @code{setRealTimeFromRTEMS} routine sets the preferred RTC TOD to the -current RTEMS TOD. - -@example -@group -void setRealTimeFromRTEMS(void) -@{ - if no RTCs are present - return - - obtain the RTEMS TOD using rtems_clock_get - invoke the deviceSetTime routine for the preferred RTC -@} -@end group -@end example - -@section getRealTime - -The @code{getRealTime} returns the preferred RTC TOD to the -caller. - -@example -@group -void getRealTime( rtems_time_of_day *tod ) -@{ - if no RTCs are present - return - - invoke the deviceGetTime routine for the preferred RTC -@} -@end group -@end example - -@section setRealTime - -The @code{setRealTime} routine sets the preferred RTC TOD to the -TOD specified by the caller. - -@example -@group -void setRealTime( rtems_time_of_day *tod ) -@{ - if no RTCs are present - return - - invoke the deviceSetTime routine for the preferred RTC -@} -@end group -@end example - -@section checkRealTime - -The @code{checkRealTime} routine returns the number of seconds -difference between the RTC TOD and the current RTEMS TOD. - -@example -@group -int checkRealTime( void ) -@{ - if no RTCs are present - return -1 - - - obtain the RTEMS TOD using rtems_clock_get - get the TOD from the preferred RTC using the deviceGetTime routine - - convert the RTEMS TOD to seconds - convert the RTC TOD to seconds - - return the RTEMS TOD in seconds - RTC TOD in seconds -@} -@end group -@end example - |