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author | Joel Sherrill <joel.sherrill@OARcorp.com> | 1997-12-01 22:06:48 +0000 |
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committer | Joel Sherrill <joel.sherrill@OARcorp.com> | 1997-12-01 22:06:48 +0000 |
commit | 7150f00f5be87fa8e37f7d00fbbef35645081138 (patch) | |
tree | 1cc7d3e1c4933404ddc1f742c7e37648cc783364 /c/src/lib/libbsp/i386/pc386/clock/ckinit.c | |
parent | Fixed test for RTEMS_HAS_POSIX_API so the executive POSIX API related (diff) | |
download | rtems-7150f00f5be87fa8e37f7d00fbbef35645081138.tar.bz2 |
Inclusion of PC386 BSP submitted by Pedro Miguel Da Cruz Neto Romano
<pmcnr@camoes.rnl.ist.utl.pt> and Jose Rufino <ruf@asterix.ist.utl.pt>
of NavIST (http://pandora.ist.utl.pt/).
Diffstat (limited to '')
-rw-r--r-- | c/src/lib/libbsp/i386/pc386/clock/ckinit.c | 285 |
1 files changed, 285 insertions, 0 deletions
diff --git a/c/src/lib/libbsp/i386/pc386/clock/ckinit.c b/c/src/lib/libbsp/i386/pc386/clock/ckinit.c new file mode 100644 index 0000000000..e02510c70e --- /dev/null +++ b/c/src/lib/libbsp/i386/pc386/clock/ckinit.c @@ -0,0 +1,285 @@ +/*-------------------------------------------------------------------------+ +| ckinit.c v1.1 - PC386 BSP - 1997/08/07 ++--------------------------------------------------------------------------+ +| This file contains the PC386 clock package. ++--------------------------------------------------------------------------+ +| (C) Copyright 1997 - +| - NavIST Group - Real-Time Distributed Systems and Industrial Automation +| +| http://pandora.ist.utl.pt +| +| Instituto Superior Tecnico * Lisboa * PORTUGAL ++--------------------------------------------------------------------------+ +| Disclaimer: +| +| This file is provided "AS IS" without warranty of any kind, either +| expressed or implied. ++--------------------------------------------------------------------------+ +| This code is based on: +| ckinit.c,v 1.4 1995/12/19 20:07:13 joel Exp - go32 BSP +| With the following copyright notice: +| ************************************************************************** +| * COPYRIGHT (c) 1989, 1990, 1991, 1992, 1993, 1994. * +| * On-Line Applications Research Corporation (OAR). * +| * All rights assigned to U.S. Government, 1994. * +| * * +| * This material may be reproduced by or for the U.S. Government pursuant * +| * to the copyright license under the clause at DFARS 252.227-7013. This * +| * notice must appear in all copies of this file and its derivatives. * +| ************************************************************************** ++--------------------------------------------------------------------------*/ + + +#include <stdlib.h> + +#include <bsp.h> +#include <irq.h> +#include <rtems/libio.h> + +/*-------------------------------------------------------------------------+ +| Constants ++--------------------------------------------------------------------------*/ +#define CLOCK_IRQ 0x00 /* Clock IRQ. */ + +/*-------------------------------------------------------------------------+ +| Macros ++--------------------------------------------------------------------------*/ +#if 0 +/* This was dropped in the last revision. Its a nice thing to know. */ +#define TICKS_PER_SECOND() \ + (1000000 / (Clock_isrs_per_tick * microseconds_per_isr)) +#endif /* 0 */ + +/*-------------------------------------------------------------------------+ +| Global Variables ++--------------------------------------------------------------------------*/ + +volatile rtems_unsigned32 Clock_driver_ticks; /* Tick (interrupt) counter. */ + rtems_unsigned32 Clock_isrs_per_tick; /* ISRs per tick. */ + rtems_unsigned32 Clock_isrs; /* ISRs until next tick. */ + +/* The following variables are set by the clock driver during its init */ + +rtems_device_major_number rtems_clock_major = ~0; +rtems_device_minor_number rtems_clock_minor; + +/*-------------------------------------------------------------------------+ +| Function: clockIsr +| Description: Interrupt Service Routine for clock (08h) interruption. +| Global Variables: Clock_driver_ticks, Clock_isrs. +| Arguments: vector - standard RTEMS argument - see documentation. +| Returns: standard return value - see documentation. ++--------------------------------------------------------------------------*/ +static rtems_isr +clockIsr(rtems_vector_number vector) +{ + /*-------------------------------------------------------------------------+ + | PLEASE NOTE: The following is directly transcribed from the go32 BSP for + | those who wish to use it with PENTIUM based machine. It needs + | to be correctly integrated with the rest of the code!!! + +--------------------------------------------------------------------------*/ + +#if 0 && defined(pentium) /* more accurate clock for PENTIUMs (not supported) */ + { + extern long long Last_RDTSC; + __asm __volatile(".byte 0x0F, 0x31" : "=A" (Last_RDTSC)); + } +#endif /* 0 && pentium */ + + Clock_driver_ticks++; + + if ( Clock_isrs == 1 ) + { + rtems_clock_tick(); + Clock_isrs = Clock_isrs_per_tick; + } + else + Clock_isrs--; + + PC386_ackIrq(vector - PC386_IRQ_VECTOR_BASE); +} /* clockIsr */ + + +/*-------------------------------------------------------------------------+ +| Function: Clock_exit +| Description: Clock cleanup routine at RTEMS exit. NOTE: This routine is +| not really necessary, since there will be a reset at exit. +| Global Variables: None. +| Arguments: None. +| Returns: Nothing. ++--------------------------------------------------------------------------*/ +void Clock_exit(void) +{ + if (BSP_Configuration.ticks_per_timeslice) + { + /* reset timer mode to standard (BIOS) value */ + outport_byte(TIMER_MODE, TIMER_SEL0 | TIMER_16BIT | TIMER_RATEGEN); + outport_byte(TIMER_CNTR0, 0); + outport_byte(TIMER_CNTR0, 0); + } +} /* Clock_exit */ + + +/*-------------------------------------------------------------------------+ +| Function: Install_clock +| Description: Initialize and install clock interrupt handler. +| Global Variables: None. +| Arguments: None. +| Returns: Nothing. ++--------------------------------------------------------------------------*/ +void +Install_clock(rtems_isr_entry isr) +{ + rtems_unsigned32 microseconds_per_isr; + + rtems_status_code status; + +#if 0 + /* Initialize clock from on-board real time clock. This breaks the */ + /* test code which assumes which assumes the application will do it. */ + { + rtems_time_of_day now; + + /* External Prototypes */ + extern void init_rtc(void); /* defined in 'rtc.c' */ + extern long rtc_read(rtems_time_of_day *); /* defined in 'rtc.c' */ + + init_rtc(); + if (rtc_read(&now) >= 0) + clock_set(&now); + } +#endif /* 0 */ + + /* Start by assuming hardware counter is large enough, then scale it until + it actually fits. */ + + Clock_driver_ticks = 0; + Clock_isrs_per_tick = 1; + + if (BSP_Configuration.microseconds_per_tick == 0) + microseconds_per_isr = 10000; /* default 10 ms */ + else + microseconds_per_isr = BSP_Configuration.microseconds_per_tick; + while (US_TO_TICK(microseconds_per_isr) > 65535) + { + Clock_isrs_per_tick *= 10; + microseconds_per_isr /= 10; + } + + Clock_isrs = Clock_isrs_per_tick; /* Initialize Clock_isrs */ + + if (BSP_Configuration.ticks_per_timeslice) + { + /* 105/88 approximates TIMER_TICK * 1e-6 */ + rtems_unsigned32 count = US_TO_TICK(microseconds_per_isr); + + status = PC386_installRtemsIrqHandler(CLOCK_IRQ, isr); + + if (status != RTEMS_SUCCESSFUL) + { + printk("Error installing clock interrupt handler!\n"); + rtems_fatal_error_occurred(status); + } + + outport_byte(TIMER_MODE, TIMER_SEL0|TIMER_16BIT|TIMER_RATEGEN); + outport_byte(TIMER_CNTR0, count >> 0 & 0xff); + outport_byte(TIMER_CNTR0, count >> 8 & 0xff); + } + + atexit(Clock_exit); +} /* Install_clock */ + + +/*-------------------------------------------------------------------------+ +| Clock device driver INITIALIZE entry point. ++--------------------------------------------------------------------------+ +| Initilizes the clock driver. ++--------------------------------------------------------------------------*/ +rtems_device_driver +Clock_initialize(rtems_device_major_number major, + rtems_device_minor_number minor, + void *pargp) +{ + Install_clock(clockIsr); /* Install the interrupt handler */ + + /* make major/minor avail to others such as shared memory driver */ + + rtems_clock_major = major; + rtems_clock_minor = minor; + + return RTEMS_SUCCESSFUL; +} /* Clock_initialize */ + + +/*-------------------------------------------------------------------------+ +| Console device driver CONTROL entry point ++--------------------------------------------------------------------------*/ +rtems_device_driver +Clock_control(rtems_device_major_number major, + rtems_device_minor_number minor, + void *pargp) +{ + if (pargp != NULL) + { + rtems_libio_ioctl_args_t *args = pargp; + + /*-------------------------------------------------------------------------+ + | This is hokey, but until we get a defined interface to do this, it will + | just be this simple... + +-------------------------------------------------------------------------*/ + + if (args->command == rtems_build_name('I', 'S', 'R', ' ')) + clockIsr(PC386_IRQ_VECTOR_BASE + CLOCK_IRQ); + else if (args->command == rtems_build_name('N', 'E', 'W', ' ')) + { + rtems_status_code status; + + status = PC386_installRtemsIrqHandler(CLOCK_IRQ, clockIsr); + + if (status != RTEMS_SUCCESSFUL) + { + printk("Error installing clock interrupt handler!\n"); + rtems_fatal_error_occurred(status); + } + } + } + + return RTEMS_SUCCESSFUL; +} /* Clock_control */ + + +/*-------------------------------------------------------------------------+ +| PLEASE NOTE: The following is directly transcribed from the go32 BSP for +| those who wish to use it with PENTIUM based machine. It needs +| to be correctly integrated with the rest of the code!!! ++--------------------------------------------------------------------------*/ + + +#if 0 && defined(pentium) + +/* This can be used to get extremely accurate timing on a pentium. */ +/* It isn't supported. [bryce] */ + +#define HZ 90.0 + +volatile long long Last_RDTSC; + +#define RDTSC()\ + ({ long long _now; __asm __volatile (".byte 0x0F,0x31":"=A"(_now)); _now; }) + +long long Kernel_Time_ns( void ) +{ + extern rtems_unsigned32 _TOD_Ticks_per_second; + + unsigned isrs_per_second = Clock_isrs_per_tick * _TOD_Ticks_per_second; + long long now; + int flags; + + disable_intr(flags); + now = 1e9 * Clock_driver_ticks / isrs_per_second + + (RDTSC() - Last_RDTSC) * (1000.0/HZ); + enable_intr(flags); + return now; +} /* Kernel_Time_ns */ + +#endif /* 0 && pentium */ |