//--- // gint - An alternative runtime environment for fx9860g and fxcg50 //--- #ifndef GINT_GINT #define GINT_GINT #include /* GINT_VERSION - the library version number gint is versioned from its repository commits on the master branch. The GINT_VERSION integer contains the short commit hash. For instance, 0x03f7c0a0 means commit 3f7c0a0. */ extern char GINT_VERSION; #define GINT_VERSION ((uint32_t)&GINT_VERSION) //--- // Library management //--- /* gint_install() - install and start gint This function installs event handlers, masks interrupts and switches VBR. Unless you are doing experimental runtime switching and you know how this function is implemented, you should not call it. */ void gint_install(void); /* gint_unload() - unload gint and give back control to the system This function restores the runtime environment saved by gint_install(). It is only called when the add-in terminates. To temporarily leave gint during execution, use gint_switch(). When possible, use syscalls without leaving gint for better performance. */ void gint_unload(void); /* gint_switch() - temporarily switch out of gint This function can be used to leave gint, restore the system's driver context, and execute code there before returning to gint. By doing this one can effectively interleave gint with the standard OS execution. The limitations are quite extreme though, so unless you know precisely why you're calling this function, you're likely doing it wrong. This switch is used to get back to the main menu and to answer TLB misses. To go back to the menu, use getkey(), or getkey_opt() with the GETKEY_MENU flag set, or call gint_osmenu() for an immediate return. @function Function to call in OS mode */ void gint_switch(void (*function)(void)); /* gint_osmenu() - switch out of gint and call the calculator's main menu This function safely invokes the calculator's main menu by unloading gint. If the user selects the gint application again in the menu, this function reloads gint and returns. Otherwise, the add-in is fully unloaded by the system and the application terminates. This function is typically called when the [MENU] key is pressed during a getkey() call. */ void gint_osmenu(void); //--- // Public functions //--- /* gint_intlevel() - configure the level of interrupts This function changes the interrupt level of the requested interrupt. Make sure you are aware of interrupt assignments to avoid breaking other code. This function is mainly used by drivers to enable the interrupts that they support. The first parameter 'intid' identifies an interrupt by its position in the sequence: IPRA & 0xf000 ; IPRA & 0x0f00 .. IPRA & 0x000f ; IPRB & 0xf000 .. For instance ID 7 refers to the low nibble of IPRB. These IDs and the range for which there are valid is heavily platform-dependent and any call to this function should be wrapped inside an MPU type check. This function will crash if the provided interrupt ID is invalid. The interrupt level should be in the range 0 (disabled) .. 15 (highest priority). @intid Interrupt ID of the targeted interrupt @level Requested interrupt level Returns the interrupt level that was assigned before the call. */ int gint_intlevel(int intid, int level); /* gint_inthandler() - configure interrupt handlers This function installs (copies) interrupt handlers in the VBR space of the application. Each handler is a 32-byte block aligned on a 32-byte boundary. When an interrupt request is accepted, the hardware jumps to a specific interrupt handler at an address that depends on the interrupt source. For safety, interrupt handlers should avoid referring to data from other blocks because the arrangement of blocks at runtime depends on event codes. The assembler program will assume that consecutive blocks in the source code will be consecutive in memory, which is not always true. Avoiding cross- references is a practical rule to avoid problems. (gint breaks this rule very often but does it carefully... I guess?) This function allows anyone to replace any interrupt handler so make sure you're not interfering with usual interrupt assignments. The first parameter event_code represents the event code associated with the interrupt. If it's not a multiple of 0x20 then you're doing something wrong. The codes are normally platform-dependent, but gint always uses SH7305 codes: SH3 platforms have a translation table. See the documentation for a list of event codes and their associated interrupts. The handler function must be an interrupt handler: it must not raise exceptions, must end with 'rts', and it will use the kernel register bank. You read that right, it must end with rts because gint's main handler saves registers besides the automated r0..r7. Do *not* use 'rte' in the handler. For convenience I allow any block size to be loaded as an interrupt handler, but it should really be a multiple of 0x20 bytes and not override other handlers. If it's not written in assembler, then you're likely doing something wrong, especially with __attribute__((interrupt_handler)) which uses rte. It is common for interrupt handlers to have a few bytes of data, such as the address of a callback function. gint often stores this data in the last bytes of the block. This function returns the VBR address of the block which has just been installed, to allow the caller to edit the parameters later. @event_code Identifier of the interrupt block @handler Address of handler function @size How many bytes to copy Returns the VBR address where the handlers was installed. */ void *gint_inthandler(int event_code, void const *handler, size_t size); #endif /* GINT_GINT */