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| -rw-r--r-- | c/src/lib/libbsp/i386/shared/irq/irq.h | 260 |
1 files changed, 260 insertions, 0 deletions
diff --git a/c/src/lib/libbsp/i386/shared/irq/irq.h b/c/src/lib/libbsp/i386/shared/irq/irq.h new file mode 100644 index 0000000000..3fba2db09e --- /dev/null +++ b/c/src/lib/libbsp/i386/shared/irq/irq.h @@ -0,0 +1,260 @@ +/* irq.h + * + * This include file describe the data structure and the functions implemented + * by rtems to write interrupt handlers. + * + * CopyRight (C) 1998 valette@crf.canon.fr + * + * This code is heavilly inspired by the public specification of STREAM V2 + * that can be found at : + * + * <http://www.chorus.com/Documentation/index.html> by following + * the STREAM API Specification Document link. + * + * The license and distribution terms for this file may be + * found in found in the file LICENSE in this distribution or at + * http://www.OARcorp.com/rtems/license.html. + * + * $Id$ + */ + +#ifndef _IRQ_H_ +#define _IRQ_H_ + +#ifdef __cplusplus +extern "C" { +#endif + +/* + * Include some preprocessor value also used by assember code + */ + +#include <irq_asm.h> +#include <rtems.h> +/*-------------------------------------------------------------------------+ +| Constants ++--------------------------------------------------------------------------*/ + +typedef enum { + /* Base vector for our IRQ handlers. */ + PC386_IRQ_VECTOR_BASE = PC386_ASM_IRQ_VECTOR_BASE, + PC_386_IRQ_LINES_NUMBER = 16, + PC_386_LOWEST_OFFSET = 0, + PC_386_MAX_OFFSET = PC_386_IRQ_LINES_NUMBER - 1, + /* + * Interrupt offset in comparison to PC386_ASM_IRQ_VECTOR_BASE + * NB : 1) Interrupt vector number in IDT = offset + PC386_ASM_IRQ_VECTOR_BASE + * 2) The same name should be defined on all architecture + * so that handler connexion can be unchanged. + */ + PC_386_PERIODIC_TIMER = 0, + + PC_386_KEYBOARD = 1, + + PC386_UART_COM2_IRQ = 3, + + PC386_UART_COM1_IRQ = 4, + + PC_386_RT_TIMER1 = 8 + +}rtems_irq_symbolic_name; + + + + +/* + * Type definition for RTEMS managed interrupts + */ +typedef unsigned char rtems_irq_prio; +typedef unsigned short rtems_i8259_masks; + +extern rtems_i8259_masks i8259s_cache; + +struct __rtems_irq_connect_data__; /* forward declaratiuon */ + +typedef void (*rtems_irq_hdl) (void); +typedef void (*rtems_irq_enable) (const struct __rtems_irq_connect_data__*); +typedef void (*rtems_irq_disable) (const struct __rtems_irq_connect_data__*); +typedef int (*rtems_irq_is_enabled) (const struct __rtems_irq_connect_data__*); + +typedef struct __rtems_irq_connect_data__ { + /* + * IRQ line + */ + rtems_irq_symbolic_name name; + /* + * handler. See comment on handler properties below in function prototype. + */ + rtems_irq_hdl hdl; + /* + * function for enabling interrupts at device level (ONLY!). + * The BSP code will automatically enable it at i8259s level. + * RATIONALE : anyway such code has to exist in current driver code. + * It is usually called immediately AFTER connecting the interrupt handler. + * RTEMS may well need such a function when restoring normal interrupt + * processing after a debug session. + * + */ + rtems_irq_enable on; + /* + * function for disabling interrupts at device level (ONLY!). + * The code will disable it at i8259s level. RATIONALE : anyway + * such code has to exist for clean shutdown. It is usually called + * BEFORE disconnecting the interrupt. RTEMS may well need such + * a function when disabling normal interrupt processing for + * a debug session. May well be a NOP function. + */ + rtems_irq_disable off; + /* + * function enabling to know what interrupt may currently occur + * if someone manipulates the i8259s interrupt mask without care... + */ + rtems_irq_is_enabled isOn; +}rtems_irq_connect_data; + +typedef struct { + /* + * size of all the table fields (*Tbl) described below. + */ + unsigned int irqNb; + /* + * Default handler used when disconnecting interrupts. + */ + rtems_irq_connect_data defaultEntry; + /* + * Table containing initials/current value. + */ + rtems_irq_connect_data* irqHdlTbl; + /* + * actual value of PC386_IRQ_VECTOR_BASE... + */ + rtems_irq_symbolic_name irqBase; + /* + * software priorities associated with interrupts. + * if irqPrio [i] > intrPrio [j] it means that + * interrupt handler hdl connected for interrupt name i + * will not be interrupted by the handler connected for interrupt j + * The interrupt source will be physically masked at i8259 level. + */ + rtems_irq_prio* irqPrioTbl; +}rtems_irq_global_settings; + + + + +/*-------------------------------------------------------------------------+ +| Function Prototypes. ++--------------------------------------------------------------------------*/ +/* + * ------------------------ Intel 8259 (or emulation) Mngt Routines ------- + */ + +/* + * function to disable a particular irq at 8259 level. After calling + * this function, even if the device asserts the interrupt line it will + * not be propagated further to the processor + */ +int pc386_irq_disable_at_i8259s (const rtems_irq_symbolic_name irqLine); +/* + * function to enable a particular irq at 8259 level. After calling + * this function, if the device asserts the interrupt line it will + * be propagated further to the processor + */ +int pc386_irq_enable_at_i8259s (const rtems_irq_symbolic_name irqLine); +/* + * function to acknoledge a particular irq at 8259 level. After calling + * this function, if a device asserts an enabled interrupt line it will + * be propagated further to the processor. Mainly usefull for people + * writting raw handlers as this is automagically done for rtems managed + * handlers. + */ +int pc386_irq_ack_at_i8259s (const rtems_irq_symbolic_name irqLine); +/* + * function to check if a particular irq is enabled at 8259 level. After calling + */ +int pc386_irq_enabled_at_i8259s (const rtems_irq_symbolic_name irqLine); +/* + * ------------------------ RTEMS Single Irq Handler Mngt Routines ---------------- + */ +/* + * function to connect a particular irq handler. This hanlder will NOT be called + * directly as the result of the corresponding interrupt. Instead, a RTEMS + * irq prologue will be called that will : + * + * 1) save the C scratch registers, + * 2) switch to a interrupt stack if the interrupt is not nested, + * 3) store the current i8259s' interrupt masks + * 4) modify them to disable the current interrupt at 8259 level (and may + * be others depending on software priorities) + * 5) aknowledge the i8259s', + * 6) demask the processor, + * 7) call the application handler + * + * As a result the hdl function provided + * + * a) can perfectly be written is C, + * b) may also well directly call the part of the RTEMS API that can be used + * from interrupt level, + * c) It only responsible for handling the jobs that need to be done at + * the device level including (aknowledging/re-enabling the interrupt at device, + * level, getting the data,...) + * + * When returning from the function, the following will be performed by + * the RTEMS irq epilogue : + * + * 1) masks the interrupts again, + * 2) restore the original i8259s' interrupt masks + * 3) switch back on the orinal stack if needed, + * 4) perform rescheduling when necessary, + * 5) restore the C scratch registers... + * 6) restore initial execution flow + * + */ +int pc386_install_rtems_irq_handler (const rtems_irq_connect_data*); +/* + * function to get the current RTEMS irq handler for ptr->name. It enables to + * define hanlder chain... + */ +int pc386_get_current_rtems_irq_handler (rtems_irq_connect_data* ptr); +/* + * function to get disconnect the RTEMS irq handler for ptr->name. + * This function checks that the value given is the current one for safety reason. + * The user can use the previous function to get it. + */ +int pc386_remove_rtems_irq_handler (const rtems_irq_connect_data*); + +/* + * ------------------------ RTEMS Global Irq Handler Mngt Routines ---------------- + */ +/* + * (Re) Initialize the RTEMS interrupt management. + * + * The result of calling this function will be the same as if each individual + * handler (config->irqHdlTbl[i].hdl) different from "config->defaultEntry.hdl" + * has been individualy connected via + * pc386_install_rtems_irq_handler(&config->irqHdlTbl[i]) + * And each handler currently equal to config->defaultEntry.hdl + * has been previously disconnected via + * pc386_remove_rtems_irq_handler (&config->irqHdlTbl[i]) + * + * This is to say that all information given will be used and not just + * only the space. + * + * CAUTION : the various table address contained in config will be used + * directly by the interrupt mangement code in order to save + * data size so they must stay valid after the call => they should + * not be modified or declared on a stack. + */ + +int pc386_rtems_irq_mngt_set(rtems_irq_global_settings* config); +/* + * (Re) get info on current RTEMS interrupt management. + */ +int pc386_rtems_irq_mngt_get(rtems_irq_global_settings**); + +#ifdef __cplusplus +} +#endif + +#endif /* _IRQ_H_ */ +/* end of include file */ |