Rename boot to bios, add sd call

Adds a call that you can make to the BIOS to read sd blocks. Useful for
the bootloader where there is not much space

sw/bios/Makefile

@@ -0,0 +1,38 @@
+CC=cl65
+CFLAGS=-T -t none -I. --cpu "65C02"
+test: CFLAGS=-T -t sim65c02 -I.
+LDFLAGS=-C link.ld -m $(NAME).map
+NAME=bios
+
+BIN=$(NAME).bin
+HEX=$(NAME).hex
+
+LISTS=lists
+
+SRCS=$(wildcard *.s) $(wildcard *.c)
+SRCS+=$(filter-out $(wildcard tests/*), $(wildcard **/*.s)) $(filter-out $(wildcard tests/*), $(wildcard **/*.c))
+OBJS+=$(patsubst %.s,%.o,$(filter %s,$(SRCS)))
+OBJS+=$(patsubst %.c,%.o,$(filter %c,$(SRCS)))
+
+all: $(HEX)
+
+$(HEX): $(BIN)
+	objcopy --input-target=binary --output-target=ihex $(BIN) $(HEX)
+	
+
+$(BIN): $(OBJS)
+	$(CC) $(CFLAGS) $(LDFLAGS) $(OBJS) -o $@
+
+%.o: %.c $(LISTS)
+	$(CC) $(CFLAGS) -l $(LISTS)/$<.list -c $< -o $@
+
+%.o: %.s $(LISTS)
+	$(CC) $(CFLAGS) -l $(LISTS)/$<.list -c $< -o $@
+
+$(LISTS):
+	mkdir -p $(addprefix $(LISTS)/,$(sort $(dir $(SRCS))))
+
+.PHONY: clean
+clean:
+	rm -rf $(OBJS) $(BIN) $(HEX) $(LISTS) $(NAME).map
+

sw/bios/boot.s

@@ -0,0 +1,14 @@
+.include "zeropage.inc"
+
+.segment "STARTUP"
+
+.export _init
+.import _load_bootsect
+
+_init:  ldx #$ff
+        txs
+        cld
+
+        jsr _load_bootsect
+        jmp $1000
+        

sw/bios/devices/interrupt.s

@@ -0,0 +1,55 @@
+.include "io.inc65"
+
+.export   _irq_int, _nmi_int
+
+.importzp sreg, ptr1
+
+.segment  "CODE"
+
+; IRQ
+_irq_int:
+        jmp (irqmap,x)
+
+_nmi_int:
+        rti
+
+irqmap:
+        .addr handle_invalid
+        .addr handle_sd_read
+
+handle_invalid:
+        rti
+
+; sreg is the pointer to store the data
+; a/y is the block address
+; send command 17 with the block address of 00/y/a
+handle_sd_read:
+        sta SD_ARG          ; send command
+        sty SD_ARG+1
+        stz SD_ARG+2
+        stz SD_ARG+3
+        lda #$11
+        sta SD_CMD
+
+@1:     lda SD_CMD          ; wait for status flag
+        and #$01
+        beq @1
+
+@2:     lda SD_CMD          ; wait for data
+        and #$02
+        beq @2
+
+        ldy #$00
+@loop:  lda SD_DATA         ; copy first 256 bytes
+        sta (sreg),y
+        iny
+        bne @loop
+
+        ldy #$00            ; copy second 256 bytes
+        inc sreg+1
+@loop2: lda SD_DATA
+        sta (sreg),y
+        iny
+        bne @loop2
+
+        rti

sw/bios/devices/io.inc65

@@ -0,0 +1 @@
+../../kernel/devices/io.inc65

sw/bios/devices/sd_card.c

@@ -0,0 +1 @@
+../../kernel/devices/sd_card.c

sw/bios/devices/sd_card.h

@@ -0,0 +1 @@
+../../kernel/devices/sd_card.h

sw/bios/devices/sd_card_asm.s

@@ -0,0 +1 @@
+../../kernel/devices/sd_card_asm.s

sw/bios/link.ld

@@ -0,0 +1,19 @@
+MEMORY
+{
+  ZP:  start = $0,    size = $100,  type = rw, define = yes;
+  SDRAM: start = $1000, size = $6ef0, type = rw, define = yes;
+  ROM: start = $8000, size = $8000, fill = yes, fillval = $ff, file = %O;
+}
+
+SEGMENTS {
+    ZEROPAGE: load = ZP,  type = zp,  define   = yes;
+    DATA:     load = ROM, type = rw,  define   = yes, run = SDRAM;
+    BSS:      load = SDRAM, type = bss, define   = yes;
+    HEAP:     load = SDRAM, type = bss, optional = yes;
+    STARTUP:  load = ROM, type = ro;
+    ONCE:     load = ROM, type = ro,  optional = yes;
+    CODE:     load = ROM, type = ro;
+    RODATA:   load = ROM, type = ro;
+    VECTORS:  load = ROM, type = ro,  start    = $FFFA;
+}
+

sw/bios/load_bootsect.c

@@ -0,0 +1,29 @@
+#include <stdint.h>
+
+#include "devices/sd_card.h"
+
+#define BOOTSECTOR_LOAD_ADDRESS 0x1000
+
+#define BOOTSIG_0 0x55
+#define BOOTSIG_1 0xaa
+
+//Should probably do this in asm
+void load_bootsect() {
+    uint32_t rca;
+    uint8_t sig[2];
+    
+    sd_init();
+	rca = sd_get_rca();
+	sd_select_card(rca);
+
+    sd_readblock(0, (uint8_t*)BOOTSECTOR_LOAD_ADDRESS);
+
+    sig[0] = ((uint8_t*)BOOTSECTOR_LOAD_ADDRESS)[510];
+    sig[1] = ((uint8_t*)BOOTSECTOR_LOAD_ADDRESS)[511];
+
+    if (sig[0] != BOOTSIG_0 || sig[1] != BOOTSIG_1) {
+        for(;;);    //maybe figure out a way to have an error message here
+    }
+
+    return;
+}

sw/bios/vectors.s

@@ -0,0 +1,14 @@
+; ---------------------------------------------------------------------------
+; vectors.s
+; ---------------------------------------------------------------------------
+;
+; Defines the interrupt vector table.
+
+.import    _init
+.import    _nmi_int, _irq_int
+
+.segment  "VECTORS"
+
+.addr      _nmi_int    ; NMI vector
+.addr      _init       ; Reset vector
+.addr      _irq_int    ; IRQ/BRK vector