coco2: memory usage

Rearrange memory
Remove drivewire
Pack things into some of the spaces
Use the LEVEL_0 option

At this point we have 28.5K user space

Still really a demo of how small we can go, and for shrinking work.

diff --git a/Kernel/platform-coco2/Makefile b/Kernel/platform-coco2/Makefile
index 5fc6af5..11914c3 100644 (file)
--- a/Kernel/platform-coco2/Makefile
+++ b/Kernel/platform-coco2/Makefile
@@ -1,14 +1,14 @@
 
-CSRCS = devices.c main.c mini_ide.c
+CSRCS = devices.c main.c mini_ide.c devtty.c
 
-C3SRCS = libc.c devtty.c
+C3SRCS = libc.c
 
 CDSRCS = discard.c mini_ide_discard.c
 
 DSRCS = ../dev/devdw.c
 
 ASRCS = crt0.s coco2.s ide.s
-ASRCS += tricks.s commonmem.s drivewire.s
+ASRCS += tricks.s commonmem.s
 
 COBJS = $(CSRCS:.c=$(BINEXT))
 C3OBJS = $(C3SRCS:.c=$(BINEXT))
@@ -22,12 +22,13 @@ CROSS_CCOPTS += -I../dev/
 all: $(OBJS)
 
 export CROSS_CC_SEGD=-mcode-section=.text3 -mfar-code-page=2
+export CROSS_CC_SEGI=-mcode-section=.page1 -mfar-code-page=2
 
 $(COBJS): %$(BINEXT): %.c
        $(CROSS_CC) $(CROSS_CCOPTS) $(CROSS_CC_SEG2) -c $<
 
 $(C3OBJS): %$(BINEXT): %.c
-       $(CROSS_CC) $(CROSS_CCOPTS) $(CROSS_CC_SEGD) -c $<
+       $(CROSS_CC) $(CROSS_CCOPTS) $(CROSS_CC_SEGI) -c $<
 
 $(CDOBJS): %$(BINEXT): %.c
        $(CROSS_CC) $(CROSS_CCOPTS) $(CROSS_CC_SEGDISC) -c $<
@@ -50,7 +51,7 @@ image: bootfuz.bin
        coco2.o discard.o ../simple.o \
        ../start.o ../version.o ../lowlevel-6809.o \
        tricks.o main.o ../timer.o ../kdata.o devices.o \
-       drivewire.o devdw.o mini_ide.o mini_ide_discard.o \
+       mini_ide.o mini_ide_discard.o \
        ../devio.o ../filesys.o ../process.o ../inode.o ../syscall_fs.o \
        ../syscall_proc.o ../syscall_other.o ../mm.o ../swap.o \
        ../tty.o ../devsys.o ../usermem.o ../syscall_fs2.o ../syscall_exec16.o \

diff --git a/Kernel/platform-coco2/README b/Kernel/platform-coco2/README
index ed531b6..d0ff48e 100644 (file)
--- a/Kernel/platform-coco2/README
+++ b/Kernel/platform-coco2/README
@@ -1,7 +1,7 @@
 COCO2
 =====
 
-COCO or Dragon 64 with an IDE port, cartridge and 64K of RAM
+COCO or Dragon 64 with an IDE port 64K of RAM
 
 Supported hardware:
        IDE (Glenside or compatible)
@@ -9,13 +9,13 @@ Supported hardware:
 Memory Map
 ==========
 0000-00FF      Interrupt stack
-0100-01FF      Vectors (then wasted - could hide libc.o in there ?)
+0100-01FF      Vectors and then libc
 0200-03FF      Display
 0400-7FFF      Code/Data for kernel (take care to keep this below 8000 and
                shuffle stuff if needed to make it fit)
-8000-EFFF      User space
-EC00-FBFF      More kernel bits
-FC00-FEFF      udata
+8000-F1FF      User space (28.5K)
+F200-FBFF      More kernel bits
+FD00-FEFF      udata
 FF00-FFFF      I/O etc
 
 
@@ -38,28 +38,4 @@ actually be doable!
 
 MPI switching
 
-Could we do a cartridge version
-- Re-order so common is in low memory
-- Support map_kernel/map_process flipping
-- Add asm helpers for user mode copying (trivial - and since we never copy
-  into kernel ROM we can optimise them a lot - one map switch only)
-- Fix IDE to support the map flip on transfers (needs little asm code
-  adding)
-- How to do discard, can we just take the hit or do we need to copy the
-  entire cartridge into high RAM, run in high RAM with discard at say
-  0xA000 and then in platform_discard switch on map_kernel cartridge
-  selection so we can let userspace blow away the upper 32K of the RAM
-  mapping.
-
-16K Cartridge version would give us space for
-- Proper video (costs us about 8K)
-- Nice loader (just 'EXEC $C000' and go) < 1K
-- Probably all of sound/joysticks/printer/floppy and a few more buffers
-- Full size user memory bank (so can run full v7 shell) 4K
-
-
-Write a loader into the cartridge start so it bootstraps off disk and runs
-nicely
-
-6847T1 lower case ?
-
+See platform-coco2cart for the actual resulting cartridge based implementation

diff --git a/Kernel/platform-coco2/config.h b/Kernel/platform-coco2/config.h
index 602a9e7..64c2968 100644 (file)
--- a/Kernel/platform-coco2/config.h
+++ b/Kernel/platform-coco2/config.h
@@ -14,12 +14,14 @@
 #define UDATA_BLKS 1
 #define CONFIG_USERMEM_DIRECT
 
+#define CONFIG_LEVEL_0         /* Minimal system */
+
 #define CONFIG_BANKS   1
 /* And swapping */
 #define SWAPDEV     0x0                /* Uses part of IDE slice 0 */
-#define SWAP_SIZE   0x40       /* 32K in 512 byte blocks */
+#define SWAP_SIZE   0x39       /* 512 byte blocks */
 #define SWAPBASE    0x8000     /* We swap the lot, including stashed uarea */
-#define SWAPTOP     0xEC00     /* so it's a round number of 512 byte sectors */
+#define SWAPTOP     0xF200     /* so it's a round number of 512 byte sectors */
 #define UDATA_SIZE  0x0200     /* one block */
 #define MAX_SWAPS   32
 
@@ -48,7 +50,7 @@ extern unsigned char vt_mangle_6847(unsigned char c);
 #define TICKSPERSEC 50   /* Ticks per second */
 #define PROGBASE    0x8000  /* also data base */
 #define PROGLOAD    0x8000  /* also data base */
-#define PROGTOP     0xEC00  /* Top of program */
+#define PROGTOP     0xF200  /* Top of program */
 
 /* We need a tidier way to do this from the loader */
 #define CMDLINE        NULL      /* Location of root dev name */
@@ -58,7 +60,7 @@ extern unsigned char vt_mangle_6847(unsigned char c);
 #define NDEVS    2        /* Devices 0..NDEVS-1 are capable of being mounted */
                           /*  (add new mountable devices to beginning area.) */
 #define TTYDEV   513    /* Device used by kernel for messages, panics */
-#define NBUFS    6       /* Number of block buffers */
+#define NBUFS    5       /* Number of block buffers */
 #define NMOUNTS         2        /* Number of mounts at a time */
 #define swap_map(x)    ((uint8_t *)(x))
 

diff --git a/Kernel/platform-coco2/devices.c b/Kernel/platform-coco2/devices.c
index f62ec4a..11fd8bb 100644 (file)
--- a/Kernel/platform-coco2/devices.c
+++ b/Kernel/platform-coco2/devices.c
@@ -29,8 +29,6 @@ struct devsw dev_tab[] =  /* The device driver switch table */
   {  nxio_open,     no_close,    no_rdwr,   no_rdwr,   no_ioctl },
   {  nxio_open,     no_close,    no_rdwr,   no_rdwr,   no_ioctl },
   {  nxio_open,     no_close,    no_rdwr,   no_rdwr,   no_ioctl },
-  /* 8: /dev/dw                DriveWire remote disk images */
-  {  dw_open,       no_close,    dw_read,   dw_write,  no_ioctl },
 };
 
 bool validdev(uint16_t dev)

diff --git a/Kernel/platform-coco2/fuzix.link b/Kernel/platform-coco2/fuzix.link
index 46404c1..a162233 100644 (file)
--- a/Kernel/platform-coco2/fuzix.link
+++ b/Kernel/platform-coco2/fuzix.link
@@ -2,11 +2,12 @@ define basesympat __sectionbase_%s__
 define lensympat __sectionlen_%s__
 section .istack load 0x0000
 section .vectors load 0x0100
+section .page1
 section .start load 0x0400
 section .text
 section .text2
 section .bss
-section .video load 0xEC00
+section .video load 0xF200
 section .data
 section .videodata
 section .common