diff options
Diffstat (limited to 'c/src/lib/libcpu/powerpc/ppc403/clock/clock.c')
| -rw-r--r-- | c/src/lib/libcpu/powerpc/ppc403/clock/clock.c | 207 |
1 files changed, 128 insertions, 79 deletions
diff --git a/c/src/lib/libcpu/powerpc/ppc403/clock/clock.c b/c/src/lib/libcpu/powerpc/ppc403/clock/clock.c index fc17de4cc8..b577f80f1a 100644 --- a/c/src/lib/libcpu/powerpc/ppc403/clock/clock.c +++ b/c/src/lib/libcpu/powerpc/ppc403/clock/clock.c @@ -33,6 +33,7 @@ #include <bsp.h> #include <clockdrv.h> +#include <rtems/libio.h> #include <stdlib.h> /* for atexit() */ @@ -42,39 +43,85 @@ volatile rtems_unsigned32 Clock_driver_ticks; static rtems_unsigned32 pit_value, tick_time; static rtems_boolean auto_restart; -rtems_device_driver Clock_initialize( - rtems_device_major_number major, - rtems_device_minor_number minor, - void *pargp, - rtems_id tid, - rtems_unsigned32 *rval -) +void Clock_exit( void ); + +/* + * These are set by clock driver during its init + */ + +rtems_device_major_number rtems_clock_major = ~0; +rtems_device_minor_number rtems_clock_minor; + +static INLINE rtems_unsigned32 get_itimer(void) { - Install_clock(Clock_isr); -} + register rtems_unsigned32 rc; + asm volatile ("mftblo %0" : "=r" ((rc))); -void -ReInstall_clock(rtems_isr_entry new_clock_isr) + return rc; +} + +/* + * ISR Handler + */ + +rtems_isr +Clock_isr(rtems_vector_number vector) { - rtems_isr_entry previous_isr; - rtems_unsigned32 isrlevel = 0; + if (!auto_restart) + { + rtems_unsigned32 clicks_til_next_interrupt; + rtems_unsigned32 itimer_value; - rtems_interrupt_disable(isrlevel); - - rtems_interrupt_catch(new_clock_isr, PPC_IRQ_PIT, - &previous_isr); + /* + * setup for next interrupt; making sure the new value is reasonably + * in the future.... in case we lost out on an interrupt somehow + */ - rtems_interrupt_enable(isrlevel); -} + itimer_value = get_itimer(); + tick_time += pit_value; -static INLINE rtems_unsigned32 get_itimer(void) -{ - register rtems_unsigned32 rc; + /* + * how far away is next interrupt *really* + * It may be a long time; this subtraction works even if + * Clock_clicks_interrupt < Clock_clicks_low_order via + * the miracle of unsigned math. + */ + clicks_til_next_interrupt = tick_time - itimer_value; - asm volatile ("mftblo %0" : "=r" ((rc))); + /* + * If it is too soon then bump it up. + * This should only happen if CPU_HPPA_CLICKS_PER_TICK is too small. + * But setting it low is useful for debug, so... + */ - return rc; + if (clicks_til_next_interrupt < 400) + { + tick_time = itimer_value + 1000; + clicks_til_next_interrupt = 1000; + /* XXX: count these! this should be rare */ + } + + /* + * If it is too late, that means we missed the interrupt somehow. + * Rather than wait 35-50s for a wrap, we just fudge it here. + */ + + if (clicks_til_next_interrupt > pit_value) + { + tick_time = itimer_value + 1000; + clicks_til_next_interrupt = 1000; + /* XXX: count these! this should never happen :-) */ + } + + asm volatile ("mtpit %0" :: "r" (clicks_til_next_interrupt)); + } + + asm volatile ( "mttsr %0" :: "r" (0x08000000)); + + Clock_driver_ticks++; + + rtems_clock_tick(); } void Install_clock(rtems_isr_entry clock_isr) @@ -131,66 +178,21 @@ void Install_clock(rtems_isr_entry clock_isr) atexit(Clock_exit); } - -rtems_isr -Clock_isr(rtems_vector_number vector) +void +ReInstall_clock(rtems_isr_entry new_clock_isr) { - if (!auto_restart) - { - rtems_unsigned32 clicks_til_next_interrupt; - rtems_unsigned32 itimer_value; - - /* - * setup for next interrupt; making sure the new value is reasonably - * in the future.... in case we lost out on an interrupt somehow - */ - - itimer_value = get_itimer(); - tick_time += pit_value; - - /* - * how far away is next interrupt *really* - * It may be a long time; this subtraction works even if - * Clock_clicks_interrupt < Clock_clicks_low_order via - * the miracle of unsigned math. - */ - clicks_til_next_interrupt = tick_time - itimer_value; - - /* - * If it is too soon then bump it up. - * This should only happen if CPU_HPPA_CLICKS_PER_TICK is too small. - * But setting it low is useful for debug, so... - */ - - if (clicks_til_next_interrupt < 400) - { - tick_time = itimer_value + 1000; - clicks_til_next_interrupt = 1000; - /* XXX: count these! this should be rare */ - } - - /* - * If it is too late, that means we missed the interrupt somehow. - * Rather than wait 35-50s for a wrap, we just fudge it here. - */ - - if (clicks_til_next_interrupt > pit_value) - { - tick_time = itimer_value + 1000; - clicks_til_next_interrupt = 1000; - /* XXX: count these! this should never happen :-) */ - } - - asm volatile ("mtpit %0" :: "r" (clicks_til_next_interrupt)); - } - - asm volatile ( "mttsr %0" :: "r" (0x08000000)); + rtems_isr_entry previous_isr; + rtems_unsigned32 isrlevel = 0; - Clock_driver_ticks++; + rtems_interrupt_disable(isrlevel); + + rtems_interrupt_catch(new_clock_isr, PPC_IRQ_PIT, + &previous_isr); - rtems_clock_tick(); + rtems_interrupt_enable(isrlevel); } + /* * Called via atexit() * Remove the clock interrupt handler by setting handler to NULL @@ -213,3 +215,50 @@ Clock_exit(void) } } +rtems_device_driver Clock_initialize( + rtems_device_major_number major, + rtems_device_minor_number minor, + void *pargp +) +{ + Install_clock( Clock_isr ); + + /* + * make major/minor avail to others such as shared memory driver + */ + + rtems_clock_major = major; + rtems_clock_minor = minor; + + return RTEMS_SUCCESSFUL; +} + +rtems_device_driver Clock_control( + rtems_device_major_number major, + rtems_device_minor_number minor, + void *pargp +) +{ + rtems_libio_ioctl_args_t *args = pargp; + + if (args == 0) + goto done; + + /* + * 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', ' ')) + { + Clock_isr(PPC_IRQ_PIT); + } + else if (args->command == rtems_build_name('N', 'E', 'W', ' ')) + { + ReInstall_clock(args->buffer); + } + +done: + return RTEMS_SUCCESSFUL; +} + |