--- /dev/null
+;/*****************************************************************************/
+;/* */
+;/* em-error.inc */
+;/* */
+;/* EM error codes */
+;/* */
+;/* */
+;/* */
+;/* (C) 2002 Ullrich von Bassewitz */
+;/* Wacholderweg 14 */
+;/* D-70597 Stuttgart */
+;/* EMail: uz@musoftware.de */
+;/* */
+;/* */
+;/* This software is provided 'as-is', without any expressed or implied */
+;/* warranty. In no event will the authors be held liable for any damages */
+;/* arising from the use of this software. */
+;/* */
+;/* Permission is granted to anyone to use this software for any purpose, */
+;/* including commercial applications, and to alter it and redistribute it */
+;/* freely, subject to the following restrictions: */
+;/* */
+;/* 1. The origin of this software must not be misrepresented; you must not */
+;/* claim that you wrote the original software. If you use this software */
+;/* in a product, an acknowledgment in the product documentation would be */
+;/* appreciated but is not required. */
+;/* 2. Altered source versions must be plainly marked as such, and must not */
+;/* be misrepresented as being the original software. */
+;/* 3. This notice may not be removed or altered from any source */
+;/* distribution. */
+;/* */
+;/*****************************************************************************/
+
+
+
+; Error codes
+EM_ERR_OK = 0 ; No error
+EM_ERR_NO_DRIVER = 1 ; No driver available
+EM_ERR_CANNOT_LOAD = 2 ; Error loading driver
+EM_ERR_INV_DRIVER = 3 ; Invalid driver
+EM_ERR_NO_DEVICE = 4 ; Device (hardware) not found
+
+
+
--- /dev/null
+;/*****************************************************************************/
+;/* */
+;/* em-kernel.inc */
+;/* */
+;/* EM kernel interface */
+;/* */
+;/* */
+;/* */
+;/* (C) 2002 Ullrich von Bassewitz */
+;/* Wacholderweg 14 */
+;/* D-70597 Stuttgart */
+;/* EMail: uz@musoftware.de */
+;/* */
+;/* */
+;/* This software is provided 'as-is', without any expressed or implied */
+;/* warranty. In no event will the authors be held liable for any damages */
+;/* arising from the use of this software. */
+;/* */
+;/* Permission is granted to anyone to use this software for any purpose, */
+;/* including commercial applications, and to alter it and redistribute it */
+;/* freely, subject to the following restrictions: */
+;/* */
+;/* 1. The origin of this software must not be misrepresented; you must not */
+;/* claim that you wrote the original software. If you use this software */
+;/* in a product, an acknowledgment in the product documentation would be */
+;/* appreciated but is not required. */
+;/* 2. Altered source versions must be plainly marked as such, and must not */
+;/* be misrepresented as being the original software. */
+;/* 3. This notice may not be removed or altered from any source */
+;/* distribution. */
+;/* */
+;/*****************************************************************************/
+
+
+
+;------------------------------------------------------------------------------
+; Driver header stuff
+
+EMD_HDR_ID = 0 ; 0x65, 0x6d, 0x64 ("emd")
+EMD_HDR_VERSION = 3 ; Interface version
+
+EMD_HDR_JUMPTAB = 4
+EMD_HDR_INSTALL = EMD_HDR_JUMPTAB+0 ; INSTALL routine
+EMD_HDR_DEINSTALL = EMD_HDR_JUMPTAB+2 ; DEINSTALL routine
+EMD_HDR_PAGECOUNT = EMD_HDR_JUMPTAB+4 ; PAGECOUNT routine
+EMD_HDR_MAP = EMD_HDR_JUMPTAB+6 ; MAP routine
+EMD_HDR_MAPCLEAN = EMD_HDR_JUMPTAB+8 ; MAPCLEAN routine
+EMD_HDR_COPYFROM = EMD_HDR_JUMPTAB+10 ; COPYFROM routine
+EMD_HDR_COPYTO = EMD_HDR_JUMPTAB+12 ; COPYTO routine
+
+EMD_HDR_JUMPCOUNT = 7 ; Number of jump vectors
+
+;------------------------------------------------------------------------------
+; Offsets into the em_copy structure
+
+EM_COPY_PAGE = 0
+EM_COPY_OFFS = 2
+EM_COPY_BUF = 3
+EM_COPY_COUNT = 5
+
+;------------------------------------------------------------------------------
+; Variables
+
+ .global _em_drv ; Pointer to driver
+
+;------------------------------------------------------------------------------
+; Driver entry points
+
+ .global emd_install
+ .global emd_deinstall
+ .global emd_pagecount
+ .global emd_map
+ .global emd_mapclean
+ .global emd_copyfrom
+ .global emd_copyto
+
+;------------------------------------------------------------------------------
+; ASM functions
+
+ .global _em_install
+ .global _em_deinstall
+ .global _em_pagecount
+ .global _em_map
+ .global _em_mapclean
+ .global _em_copyfrom
+ .global _em_copyto
+
+
--- /dev/null
+#
+# Makefile for the extended memory library
+#
+
+.SUFFIXES: .o .s .c
+
+%.o: %.c
+ @$(CC) $(CFLAGS) $<
+ @$(AS) -g -o $@ $(AFLAGS) $(*).s
+
+%.o: %.s
+ @$(AS) -g -o $@ $(AFLAGS) $<
+
+C_OBJS = em_load.o
+
+S_OBJS = em-kernel.o \
+ em_copyto.o \
+ em_copyfrom.o \
+ em_map.o \
+ em_mapclean.o \
+ em_pagecount.o \
+ em_unload.o \
+
+
+all: $(C_OBJS) $(S_OBJS)
+
+clean:
+ @rm -f *~
+ @rm -f $(C_OBJS:.o=.s)
+ @rm -f $(C_OBJS)
+ @rm -f $(S_OBJS)
+
+
--- /dev/null
+;
+; Ullrich von Bassewitz, 2002-11-29
+;
+; Common functions of the extended memory API.
+;
+
+ .export _em_install, _em_deinstall
+
+ .import return0
+ .importzp ptr1
+
+ .include "em-kernel.inc"
+ .include "em-error.inc"
+
+
+;----------------------------------------------------------------------------
+; Variables
+
+
+.bss
+_em_drv: .res 2 ; Pointer to driver
+
+; Jump table for the driver functions.
+.data
+emd_vectors:
+emd_install: jmp $0000
+emd_deinstall: jmp $0000
+emd_pagecount: jmp $0000
+emd_map: jmp $0000
+emd_mapclean: jmp $0000
+emd_copyfrom: jmp $0000
+emd_copyto: jmp $0000
+
+; Driver header signature
+.rodata
+emd_sig: .byte $65, $6d, $64, $00 ; "emd", version
+emd_sig_len = * - emd_sig
+
+
+;----------------------------------------------------------------------------
+; unsigned char __fastcall__ em_install (void* driver);
+; /* Install the driver once it is loaded */
+
+
+_em_install:
+ sta _em_drv
+ sta ptr1
+ stx _em_drv+1
+ stx ptr1+1
+
+; Check the driver signature
+
+ ldy #emd_sig_len-1
+@L0: lda (ptr1),y
+ cmp emd_sig,y
+ bne inv_drv
+ dey
+ bpl @L0
+
+; Copy the jump vectors
+
+ ldy #EMD_HDR_JUMPTAB
+ ldx #0
+@L1: inx ; Skip the JMP opcode
+ jsr copy ; Copy one byte
+ jsr copy ; Copy one byte
+ cpx #(EMD_HDR_JUMPCOUNT*3)
+ bne @L1
+
+ jmp emd_install ; Call driver install routine
+
+; Driver signature invalid
+
+inv_drv:
+ lda #EM_ERR_INV_DRIVER
+ ldx #0
+ rts
+
+; Copy one byte from the jump vectors
+
+copy: lda (ptr1),y
+ iny
+set: sta emd_vectors,x
+ inx
+ rts
+
+;----------------------------------------------------------------------------
+; void __fastcall__ em_deinstall (void);
+; /* Deinstall the driver before unloading it */
+
+_em_deinstall:
+ jsr emd_deinstall ; Call driver routine
+
+; Point all jump vectors to return0
+
+ ldx #0
+@L1: inx ; Skip JMP opcode
+ lda #<return0
+ jsr set
+ lda #>return0
+ jsr set
+ cpx #(EMD_HDR_JUMPCOUNT*3)
+ bne @L1
+
+ rts
+
+
--- /dev/null
+;
+; Ullrich von Bassewitz, 2002-11-29
+;
+; void __fastcall__ em_copyfrom (const struct em_copy* copy_data);
+; /* Copy from extended into linear memory */
+
+
+ .include "em-kernel.inc"
+
+ _em_copyfrom = emd_copyfrom ; Use driver entry
+
--- /dev/null
+;
+; Ullrich von Bassewitz, 2002-11-29
+;
+; void __fastcall__ em_copyto (const struct em_copy* copy_data);
+; /* Copy from linear into extended memory */
+
+
+ .include "em-kernel.inc"
+
+ _em_copyto = emd_copyto ; Use driver entry
+
--- /dev/null
+/*****************************************************************************/
+/* */
+/* em_load.c */
+/* */
+/* Loader module for EM drivers */
+/* */
+/* */
+/* */
+/* (C) 2002 Ullrich von Bassewitz */
+/* Wacholderweg 14 */
+/* D-70597 Stuttgart */
+/* EMail: uz@musoftware.de */
+/* */
+/* */
+/* This software is provided 'as-is', without any expressed or implied */
+/* warranty. In no event will the authors be held liable for any damages */
+/* arising from the use of this software. */
+/* */
+/* Permission is granted to anyone to use this software for any purpose, */
+/* including commercial applications, and to alter it and redistribute it */
+/* freely, subject to the following restrictions: */
+/* */
+/* 1. The origin of this software must not be misrepresented; you must not */
+/* claim that you wrote the original software. If you use this software */
+/* in a product, an acknowledgment in the product documentation would be */
+/* appreciated but is not required. */
+/* 2. Altered source versions must be plainly marked as such, and must not */
+/* be misrepresented as being the original software. */
+/* 3. This notice may not be removed or altered from any source */
+/* distribution. */
+/* */
+/*****************************************************************************/
+
+
+
+#include <string.h>
+#include <fcntl.h>
+#include <modload.h>
+#include <em.h>
+#include <em/em-kernel.h>
+
+
+
+unsigned char __fastcall__ em_load (unsigned char driver)
+/* Load the extended memory driver and return an error code. */
+{
+ return EM_ERR_NO_DRIVER;
+}
+
+
+
+unsigned char __fastcall__ em_load_driver (const char* name)
+/* Load an extended memory driver and return an error code */
+{
+ static struct mod_ctrl ctrl = {
+ read /* Read from disk */
+ };
+ unsigned char Res;
+
+ /* Check if we do already have a driver loaded. If so, remove it. */
+ if (em_drv != 0) {
+ em_deinstall ();
+ }
+
+ /* Now open the file */
+ ctrl.callerdata = open (name, O_RDONLY);
+ if (ctrl.callerdata >= 0) {
+
+ /* Load the module */
+ Res = mod_load (&ctrl);
+
+ /* Close the input file */
+ close (ctrl.callerdata);
+
+ /* Check the return code */
+ if (Res == MLOAD_OK) {
+
+ /* Check the driver signature, install the driver */
+ return em_install (ctrl.module);
+
+ }
+ }
+
+ /* Error loading the driver */
+ return EM_ERR_CANNOT_LOAD;
+}
+
+
+
--- /dev/null
+;
+; Ullrich von Bassewitz, 2002-11-29
+;
+; void* __fastcall__ em_map (unsigned page);
+; /* Unmap the current page from memory and map a new one. The function returns
+; * a pointer to the location of the page in memory.
+; */
+
+
+ .include "em-kernel.inc"
+
+ _em_map = emd_map ; Use driver entry
+
--- /dev/null
+;
+; Ullrich von Bassewitz, 2002-11-29
+;
+; void* __fastcall__ em_mapclean (unsigned page);
+; /* Unmap the current page from memory and map a new one. The function returns
+; * a pointer to the location of the page in memory. This function differs from
+; * em_map_page() in that it will discard the contents of the currently mapped
+; * page, assuming that the page has not been modified or that the modifications
+; * are no longer needed, if this leads to better performance. NOTE: This does
+; * NOT mean that the contents of currently mapped page are always discarded!
+; */
+
+
+ .include "em-kernel.inc"
+
+ _em_mapclean = emd_mapclean ; Use driver entry
+
--- /dev/null
+;
+; Ullrich von Bassewitz, 2002-11-29
+;
+; unsigned em_pagecount (void);
+; /* Return the total number of 256 byte pages available in extended memory. */
+
+
+ .include "em-kernel.inc"
+
+ _em_pagecount = emd_pagecount ; Use driver entry
+
--- /dev/null
+;
+; Ullrich von Bassewitz, 2002-11-29
+;
+; unsigned char __fastcall__ em_unload (void);
+; /* Unload the currently loaded driver. */
+
+
+ .include "em-kernel.inc"
+ .include "em-error.inc"
+ .include "modload.inc"
+
+ .import return0
+
+
+_em_unload:
+ lda _em_drv
+ ora _em_drv+1
+ beq no_driver ; No driver
+
+ jsr _em_deinstall ; Deinstall the driver
+
+ lda _em_drv
+ ldx _em_drv+1
+ jsr _mod_free ; Free the driver
+
+ jmp return0
+
+no_driver:
+ tax ; X = 0
+ lda #EM_ERR_NO_DRIVER
+ rts
+
projects / cc65 / commitdiff